Electric power tool using battery pack as power supply thereof, and adapter therefor

A power tool which uses a battery pack as a power supply, and its adapter

The present invention relates to a power tool which uses a battery pack as a power supply, and its adapter.

A power tool which makes two battery packs a U. S. Pat. No. 5, 028, 858 specification with a power supply is indicated. In this power tool, two battery packs are connected in series and it has composition which a motor drives by a high voltage. Thereby, compared with what uses one battery pack as a power supply, an usable high output can be demonstrated to heavy work.

When a battery pack is connected in series, a big burden may be applied to one battery pack. For example, if charge levels differ between two battery packs, fault electric discharge will be carried out and one battery pack will be further charged by opposite direction with a battery pack of another side (reverse charge). In this case, a serious damage will be received, and that degradation will advance greatly, or use of one battery pack will become impossible.

In a power tool described above about the above-mentioned problem, when a charge level of two battery packs is measured, respectively and a charge level of a battery pack separates from tolerance level, an electric power supply circuit which supplies electric power to a motor is electrically cut from a battery pack. According to this composition, fault electric discharge of a battery pack can be prevented and a serious damage to a battery pack can be avoided. A plurality of battery packs are not restricted to a power tool connected in series, but a plurality of battery packs can apply such composition effectively also in a power tool connected in parallel and a power tool which uses only a single battery pack.

<p num="0005">In recent years, a charge level is supervised itself and a battery pack which has an alarm function which outputs an alarm signal with a fall of a charge level, and an autostop function which stops electric discharge automatically with a fall of a charge level is developed. According to this kind of battery pack, it becomes unnecessary to measure a charge level of a battery pack in a power tool, and can make electric structure of a power tool simple. However, when a charge level of a battery pack cannot be measured in a power tool, are carried out and a battery pack of the old model which has neither an alarm function nor an autostop function is used, there is a possibility that fault electric discharge of the battery pack may be carried out. Irrespective of existence of an alarm function or an autostop function, art in which fault electric discharge of a battery pack can be prevented appropriately is needed.</p>

<p num="0006">This art is embodied by adapter which connects at least one battery pack of each other with a main part of a power tool. A connector area with this adapter removable on a main part of a power tool, and at least one battery accession department with a removable battery pack, An electric power supply circuit which electrically connects a battery pack attached to a battery accession department to a main part of a power tool attached by connector area, A measuring part which measures an index corresponding to a charge level of a battery pack attached to a battery accession department, A receiving part which receives an alarm signal which a battery pack attached to a battery accession department outputs, a measurement value by a measuring part, and a received alarm signal are embraced, and it has a control part which stops or restricts an electric power supply to a main part of a power tool.</p><p num="0007">This adapter can embrace an alarm signal which a battery pack outputs, and can stop or restrict electric discharge of a battery pack. Even when an alarm signal is not outputted from a battery pack, this adapter can be fit for a charge level of a battery pack measured itself, and can stop or restrict electric discharge of a battery pack. therefore -- having an alarm function in which a battery pack outputs an alarm signal か否か -- irrespective of -- fault electric discharge of a battery pack can be prevented. In addition, when a battery pack has an alarm function, electric discharge of a battery pack can be appropriately stopped or restricted by using the alarm signal.</p><p num="0008">It is preferred that an alarm signal received by receiving part in the above-mentioned adapter is a signal which a battery pack outputs with a fall of a charge level. In this case, as for a control part, when an alarm signal is received, it is preferred to stop electric discharge of a battery pack.</p><p num="0009">It is preferred that a measuring part measures output voltage of a battery pack in the above-mentioned adapter. In a battery pack, the output voltage declines with a fall of a charge level. Therefore, a charge level of a battery pack can be correctly grasped by measuring output voltage of a battery pack.</p><p num="0010">It is preferred that a control part stops or restricts an electric power supply to a main part of a power tool in an adapter of one embodiment when an alarm signal is received by receiving part, or when a measurement value by a measuring part separates from predetermined tolerance level. According to this embodiment, when an alarm signal is received, electric discharge of a battery pack is stopped or restricted irrespective of a charge level of a measured battery pack. When a measurement value by a measuring part separates from predetermined tolerance level on the other hand, electric discharge of a battery pack is stopped irrespective of existence of reception of an alarm signal. Fault electric discharge of an adapter can be prevented without a battery pack attached to an adapter distinguishing whether it is having an alarm function according to this embodiment.</p><p num="0011">It is preferred for it to be distinguished whether it is that a control part has an alarm function about a battery pack attached to a battery accession department in an adapter of other one embodiments. And when a battery pack has an alarm function, only when a measurement value by a measuring part is disregarded and an alarm signal is received, it is preferred [a control part] to stop or restrict an electric power supply to a main part of a power tool. In this form, when a battery pack has an alarm function, priority is given to an alarm signal which a battery pack outputs over a charge level measured by an adapter. Because, it is because a measurement value in an adapter is excelled in accuracy when ways of judgment by a battery pack are many.</p><p num="0012">It is preferred for it to be distinguished whether it is that a control part has an autostop function which stops electric discharge automatically with a fall of a charge level about a battery pack attached to a battery accession department in the above-mentioned adapter of an embodiment. And as for a control part, when a battery pack attached to a battery accession department has an alarm function, it is preferred that a measurement value by a measuring part is disregarded. In this form, when a battery pack has an autostop function, priority is given to a stop of spontaneous electric discharge by a battery pack, and processing which stops or restricts electric discharge with a charge level measured by an adapter is not performed. According to this form, fault electric discharge can be appropriately prevented about both a battery pack which has an alarm function a battery pack which has an autostop function and a battery pack which does not have both those functions.</p><p num="0013">Other adapters embodied by this art, A connector area in which are an adapter which connects at least one battery pack of each other with a main part of a power tool, and a power tool is removable on a main part, An electric power supply circuit where a battery pack electrically connects a battery pack attached to at least one removable battery accession department and battery accession department to a main part of a power tool attached by connector area, It responded to a measurement value by measuring part which measures an index corresponding to a charge level of a battery pack attached to a battery accession department, and a measuring part, and has a control part which stops or restricts an electric power supply to a main part of a power tool. The control part can distinguish whether it is having an autostop function a battery pack attached to a battery accession department stopping electric discharge automatically with a fall of a charge level. And a control part disregards a measurement value by a measuring part, when a battery pack attached to a battery accession department has an autostop function. When a battery pack attached to a battery accession department does not have an autostop function and a measurement value by a measuring part separates from predetermined tolerance level on the other hand, an electric power supply to a main part of a power tool is stopped or restricted.</p><p num="0014">This adapter can stop electric discharge of a battery pack according to a charge level of a measured battery pack. However, when a battery pack has an autostop function, priority is given to a stop of spontaneous electric discharge by a battery pack, and processing which stops or restricts electric discharge with a charge level measured by an adapter is not performed. therefore -- that a battery pack has an autostop function か否か -- irrespective of -- fault electric discharge of a battery pack can be prevented. About a battery pack which has an autostop function, electric discharge of a battery pack can be stopped because of suitable timing by giving priority to the autostop function.</p><p num="0015">In an adapter concerning this art, a plurality of battery accession departments can be provided so that a plurality of battery packs can be used. In this case, an electric power supply circuit connects to a main part of a power tool a plurality of battery packs attached to a plurality of battery accession departments in series or in parallel.</p><p num="0016">In composition to which an electric power supply circuit connects a plurality of battery packs in series, unless a battery pack is attached to all battery accession departments, the electric power supply circuit cannot form a closed way. That is, even if a battery pack is attached only to some battery accession departments, apparatus (for example, control part) in an adapter cannot receive an electric power supply from a battery pack. Apparatus in an adapter can start the operation only after a battery pack is attached to all the battery accession departments.</p><p num="0017">In one embodiment which starts this art about the above-mentioned point, when an electric power supply circuit is the composition of connecting a plurality of battery packs in series, a pair of electric power input terminals provided in each battery accession department can electrically be connected via a diode. Here, a pair of electric power input terminals are terminals connected to a right extreme child and a cathode terminal of a battery pack, respectively. According to this embodiment, the electric power supply circuit can form a closed way, and having attached a battery pack only to some battery accession departments can also supply electric power to apparatus in an adapter from a battery pack.</p><p num="0018">Art concerning an adapter mentioned above is also directly applicable to a power tool. That is, the power tool itself may possess composition concerning an adapter mentioned above.</p><p num="0019">A motor which a power tool of one embodiment concerning this art is a power tool which uses at least one battery pack as a power supply, and drives a tool, An electric power supply circuit where a battery pack electrically connects to a motor a battery pack attached to at least one removable battery accession department and battery accession department, A measuring part which measures an index corresponding to a charge level of a battery pack attached to a battery accession department, A receiving part which receives an alarm signal which a battery pack attached to a battery accession department outputs, a measurement value by a measuring part, and a received alarm signal were embraced, and it has a control part which stops or restricts an electric power supply to a motor.</p><p num="0020">According to this power tool, fault electric discharge of a battery pack can be prevented irrespective of existence of an alarm function. In addition, when a battery pack has an alarm function, electric discharge of a battery pack can be stopped or restricted to suitable timing by using the alarm signal.</p><p num="0021">A motor which a power tool of other embodiments concerning this art is a power tool which uses at least one battery pack as a power supply, and drives a tool, An electric power supply circuit where a battery pack electrically connects to a motor a battery pack attached to at least one removable battery accession department and battery accession department, It responded to a measurement value by measuring part which measures an index corresponding to a charge level of a battery pack attached to a battery accession department, and a measuring part, and has a control part which stops or restricts an electric power supply to a motor. The control part can distinguish whether it is having an autostop function a battery pack attached to a battery accession department stopping electric discharge automatically with a fall of a charge level. And when a battery pack in which a control part was attached to a battery accession department has an autostop function, A measurement value by a measuring part is disregarded, and when a battery pack attached to a battery accession department does not have an autostop function and a measurement value by a measuring part separates from predetermined tolerance level, an electric power supply to a motor is stopped or restricted.</p><p num="0022">According to this power tool, fault electric discharge of a battery pack can be prevented irrespective of existence of an autostop function. In addition, when a battery pack has an autostop function, giving priority to the autostop function can stop electric discharge of a battery pack because of suitable timing.</p>

<figref num="1">An outline view showing an adapter of an example.</figref>

<figref num="2">An outline view showing the tool side unit of an adapter.</figref>

<figref num="3">An outline view showing the battery side unit of an adapter.</figref>

<figref num="4">A figure showing an adapter of Example 1, a main part of a power tool, and circuit composition of a battery pack (those with alarm functional).</figref>

<figref num="5">A figure showing an adapter of Example 1, a main part of a power tool, and circuit composition of a battery pack (with no alarm function).</figref>

<figref num="6">A figure showing an adapter of Example 2, a main part of a power tool, and circuit composition of a battery pack (those with alarm functional, those with ID terminal).</figref>

<figref num="7">A figure showing an adapter of Example 2, a main part of a power tool, and circuit composition of a battery pack (alarm functional nothing one, those with ID terminal).</figref>

<figref num="8">A figure showing an adapter of Example 2, a main part of a power tool, and circuit composition of a battery pack (those with autostop functional, those with ID terminal).</figref>

<figref num="9">A figure showing an adapter of Example 3, a main part of a power tool, and circuit composition of a battery pack (those with autostop functional, those with ID terminal).</figref>

<figref num="10">A figure showing an adapter of Example 3, a main part of a power tool, and circuit composition of a battery pack (autostop functional nothing one, those with ID terminal).</figref>

<figref num="11">An outline view showing an integral-type adapter.</figref>

<figref num="12">An outline view shown where a power tool of an example is attached to a battery pack.</figref>

<figref num="13">An outline view showing a power tool of an example where a battery pack is removed.</figref>

<figref num="14">An outline view showing a power tool of an example which removed a battery pack from a lower part.</figref>

<figref num="15">A figure showing a main part of a power tool of Example 4, and circuit composition of a battery pack (those with alarm functional).</figref>

<figref num="16">A figure showing a main part of a power tool of Example 5, and circuit composition of a battery pack (those with alarm functional, those with ID terminal).</figref>

<figref num="17">A figure showing a main part of a power tool of Example 6, and circuit composition of a battery pack (those with autostop functional, those with ID terminal).</figref>

<p>Adapter 100 of Example 1 is explained with reference to drawings. Drawing 1, Drawing 2, and Drawing 3 show appearance of adapter 100. As shown in Drawing 1, Drawing 2, and Drawing 3, adapter 100 is apparatus for electrically connecting two battery packs 10 to main part 52 of a power tool. Here, rated voltage of main part 52 of a power tool is 36 v, and rated voltage of each battery pack 10 is 18 v. Usually, as for main part 52 of a power tool, nominal voltage cannot use a 36-v battery pack, and nominal voltage cannot use an 18-v battery pack. However, according to adapter 100 of this example, rated voltage can use a 36-v power tool using two battery packs 10 whose nominal voltage is 18 v, without nominal voltage needing a 36-v battery pack.</p><p>Art explained in this specification is not limited to specific rated voltage or nominal voltage, but can be applied to a power tool of various rated voltage, or a battery pack of various nominal voltage. Art explained in this specification is also applicable to an adapter which connects 1 or three or more battery packs to a main part of a power tool.</p><p>Although main part 52 of a power tool shown in a drawing is an example, it is a main part of electric ブロワー. This power tool drives a ventilation fan built in main part 52 according to operation to main switch 54, and blows off air from tip 53a of nozzle 53. Electric ブロワー is a power tool mainly used outdoors, and is used for work which blows and collects fallen leaves and garbage. Adapter 100 is not restricted to electric ブロワー, but can be widely used for various cordless power tools which use a battery pack as a power supply.</p><p>As shown in Drawing 1, adapter 100 is with tool side unit 102 removable on main part 52 of a power tool, Two battery packs 10 are provided with electrical cord 104 which has connected mutually removable battery side unit 106, and tool side unit 102 and battery side unit 106. As shown in Drawing 2, connector area 102a is provided in tool side unit 102. Connector area 102a is removably engaged to battery accession department 56a provided in main part 52 of a power tool. Here, nominal voltage is removably constituted in a 36-v battery pack, and battery accession department 56a provided in main part 52 of a power tool has structure where nominal voltage cannot attach 18-v battery pack 10 directly.</p><p>As shown in Drawing 3, two battery accession departments 106a are provided in battery side unit 106. Each battery accession department 106a engages with connector area 10a of battery pack 10 removably. Thereby, nominal voltage can attach 18-v battery pack 10 to each battery accession department 106a removably. Two battery packs 10 attached to battery side unit 106 are electrically connected to main part 52 of a power tool attached to tool side unit 102, and electric power from two battery packs 10 is supplied to the main part 52 concerned via adapter 100.</p><p>Two displays for indication 130 are formed in battery side unit 106. Two displays for indication 130 are located above two battery accession departments 106a, respectively. Although each display for indication 130 is an example, it is a light emitting diode. One display for indication 130 displays a charge level of battery pack 10 attached to one battery accession department 106a, and display for indication 130 of another side displays a charge level of battery pack 10 attached to battery accession department 106a of another side. As shown in Drawing 1, hook 108 for a user to hang battery side unit 106 on a belt etc. is provided in battery side unit 106.</p><p>Drawing 4 shows circuit composition of main part 52 of a power tool, battery pack 10, and adapter 100. First, circuit composition of main part 52 of a power tool is explained. As shown in Drawing 4, main part 52 of a power tool is provided with motor 60, electric power supply circuit 62, main switch 54, speed regulation circuit 66, and power FET64, transistor 68, partial pressure circuit 70, anode input terminal 72, cathode input terminal 74, and alarm terminal 78.</p><p>Anode input terminal 72, cathode input terminal 74, and alarm terminal 78 are arranged at battery accession department 56a of main part 52 of a power tool, and are electrically connected to adapter 100 attached to battery accession department 56a. Anode input terminal 72 and cathode input terminal 74 are electrically connected to motor 60 by electric power supply circuit 62, and electric power inputted from adapter 100 is supplied to motor 60 through electric power supply circuit 62. Motor 60 is a motor which drives a tool (here ventilation fan). Main switch 54 and power FET64 is provided in electric power supply circuit 62. Main switch 54 and power FET64 can open, respectively and close electric power supply circuit 62 electrically by turning on/turning off.</p><p>Speed regulation circuit 66 is interlocked with main switch 54. If a user turns on main switch 54, speed regulation circuit 66 will output an ON signal to a gate terminal of power FET64. Thereby, both main switch 54 and power FET64 are turned on, and electric power supply circuit 62 is closed electrically (connection). Here, speed regulation circuit 66 can perform PWM control to power FET64. That is, speed regulation circuit 66 changes a period when a user makes power FET64 turn on according to the amount of operations applied to main switch 54 while making power FET64 turn on intermittently. Thereby, revolving speed of motor 60 is adjusted according to the amount of operations applied to main switch 54.</p><p>A gate terminal of power FET64 is connected to electric power supply circuit 62 which stands in a row in cathode input terminal 74 via transistor 68. And alarm terminal 78 is connected to a gate of transistor 68 via partial pressure circuit 70. An alarm signal which adapter 100 outputs is inputted into alarm terminal 78. If an alarm signal is inputted into alarm terminal 78, transistor 68 will be turned on and a gate terminal of power FET64 will be connected to cathode input terminal 74 of Loule Bell (zero bolt). As a result, irrespective of an ON signal from speed regulation circuit 66, power FET64 is turned off and a drive of motor 60 is stopped. Thus, when an alarm signal which adapter 100 outputs is received, main part 52 of a power tool is constituted so that a drive of motor 60 may be stopped.</p><p>Next, circuit composition of battery pack 10 is explained. Battery pack 10, It has five battery cells 20 and battery controller 22 which were connected in series, the 1st transistor 24, the 2nd transistor 26, the 3rd transistor 28, fuse 30, anode output terminal 32, cathode output terminal 34, high-level signal terminal 36, and alarm terminal 38.</p><p>Anode output terminal 32, cathode output terminal 34, high-level signal terminal 36, and alarm terminal 38 are arranged at connector area 10a of battery pack 10, and are electrically connected to adapter 100 by which battery pack 10 was attached. It is electrically connected to five battery cells 20, and anode output terminal 32 and cathode output terminal 34 output electric power discharged from five battery cells 20 to adapter 100. Although each battery cell 20 is an example, it is a lithium ion cell and the nominal voltage is 3.6 v. Battery pack 10 may contain not only five battery cells 20 but arbitrary numbers (1 or plurality) of battery cells 20.</p><p>Via fuse 30, it is connected to anode output terminal 32, and high-level signal terminal 36 outputs a high-level signal (here 18 v). High-level signal terminal 36 is a terminal used by a charger which charges battery pack 10, and is not used depending on adapter 100.</p><p>Alarm terminal 38 is connected to battery controller 22 via three transistors 24, 26, and 28. Alarm terminal 38 is a terminal into which an alarm release signal from adapter 100 is inputted while being a terminal which outputs an alarm signal to adapter 100. Battery controller 22 is supervising a charge level of each battery cell 20 by measuring voltage of each battery cell 20. And when a charge level of at least one battery cell 20 separates from tolerance level, battery controller 22 judges that electric discharge should be stopped inside, and outputs an alarm signal from alarm terminal 38. Battery controller 22 continues outputting an alarm signal until an alarm release signal from adapter 100 is inputted. Thus, battery pack 10 has an alarm function which outputs an alarm signal with a fall of an own charge level.</p><p>Here, although it is an example, explanation is added about output operation of an alarm signal by battery pack 10, and reception operation of an alarm release signal. When there is no problem in a charge level of battery cell 20, battery controller 22 turns on the 2nd transistor 26. If the 2nd transistor 26 is turned on, the 1st transistor 24 will be turned on and alarm terminal 38 will output a high-level signal. This high-level signal is not an alarm signal but a signal which shows that battery pack 10 is usable. When it is judged from this state that battery controller 22 should stop electric discharge inside, the 2nd transistor 26 is turned off. If the 2nd transistor 26 is turned off, the 1st transistor 24 will also be turned off and alarm terminal 38 will be electrically insulated within battery pack 10. That is, alarm terminal 38 outputs a signal of high impedance. A signal of this high impedance is an alarm signal which battery pack 10 outputs.</p><p>On the other hand, an alarm release signal from adapter 100 is received using the 3rd transistor 28. As described above, when there is no problem in a charge level of battery cell 20, the 1st transistor 24 is turned on. If the 1st transistor 24 is turned on, the 3rd transistor 28 will also be turned on and a signal of Loule Bell (zero bolt) will be inputted into battery controller 22 from the 3rd transistor 28. Since battery controller 22 is outputted [an alarm signal], when the 2nd transistor 26 is turned off from this state, the 1st transistor 24 and the 3rd transistor 28 are also turned off. As a result, a signal of high impedance is inputted into battery controller 22 from the 3rd transistor 28. Then, when an alarm release signal is inputted into alarm terminal 38 from adapter 100, the 3rd transistor 28 is turned on again. Here, an alarm release signal of adapter 100 is a high-level signal. ON of the 3rd transistor 28 will input a signal of Loule Bell into battery controller 22 again from the 3rd transistor 28. In response to a signal of this Loule Bell, battery controller 22 turns on the 2nd transistor 26, and stops an output of an alarm signal.</p><p>Next, circuit composition of adapter 100 is explained. Adapter 100, Battery side [114 or 2 cathode input terminals of two anode input terminals / 112 or 2] alarm terminal 118, main controller 150, alarm input-and-output circuit 154, electric power supply circuit 160, and power FET162, current detecting circuit 164, shunt resistance 166, anode output terminal 172, It has cathode output terminal 174 and tool side alarm terminal 178.</p><p>One anode input terminal 112, one cathode input terminal 114, and one battery side alarm terminal 118, It is arranged at one battery accession department 106a, and is electrically connected to one anode output terminal 32, cathode output terminal 34, and alarm terminal 38 of battery pack 10, respectively. Anode input terminal 112 of another side, cathode input terminal 114 of another side, and battery side alarm terminal 118 of another side, It is arranged at battery accession department 106a of another side, and is electrically connected to anode output terminal 32, cathode output terminal 34, and alarm terminal 38 of battery pack 10 of another side, respectively. Anode output terminal 172, cathode output terminal 174, and tool side alarm terminal 178 are arranged at connector area 102a, and are electrically connected to anode input terminal 72, cathode input terminal 74, and alarm terminal 78 of main part 52 of a power tool, respectively.</p><p>Anode input terminal 112 in which electric power supply circuit 160 is arranged at one battery accession department 106a, Cathode input terminal 114 which electrically connected with anode output terminal 172, and while is the same and is arranged at battery accession department 106a, It electrically connected with anode input terminal 112 arranged at battery accession department 106a of another side, and has electrically connected to cathode output terminal 174 cathode input terminal 114 similarly arranged at battery accession department 106a of another side. Thereby, two battery packs 10 attached to adapter 100 are connected in series to main part 52 of a power tool, and electric power is supplied to motor 60 of main part 52 on abbreviated 36 v voltage. Electric power from two battery packs 10 is supplied also to main controller 150 via power supply circuit 152.</p><p>Power FET162 and shunt resistance 166 are provided in electric power supply circuit 160. In shunt resistance 166, voltage according to current which flows into electric power supply circuit 160 arises. Voltage which arose in shunt resistance 166 is inputted into main controller 150 via current detecting circuit 164. Main controller 150 outputs an alarm signal to main part 52 of a power tool from tool side alarm terminal 178 first, when inputted voltage exceeds tolerance level. As explained previously, if an alarm signal is outputted from adapter 100, by main part 52 of a power tool, power FET64 will be turned off, a drive of motor 60 will be stopped, and electric discharge of battery pack 10 will be forbidden by it. Here, for a certain reason, also after adapter 100 outputs an alarm signal, suppose that discharge current from battery pack 10 was detected. In this case, main controller 150 turns off power FET162 in adapter 100, and opens electric power supply circuit 160 electrically (cutting). Thereby, excessive current can be certainly prevented from flowing into battery pack 10 and motor 60. Adapter 100 can also be considered as composition which turns off power FET162, without outputting an alarm signal to main part 52 of a power tool. According to this composition, main part 52 of a power tool does not necessarily need to be provided with alarm terminal 78. Here, even when power FET162 is turned off, an electric power supply from battery pack 10 to main controller 150 is continued. Power FET162 may be a switching element of other kinds.</p><p>It is electrically connected to battery side alarm terminal 118, and main controller 150 can receive an alarm signal from battery pack 10. Main controller 150 can also output an alarm release signal to battery pack 10 to battery pack 10 from battery side alarm terminal 118. Main controller 150 will output an alarm signal to main part 52 of a power tool from tool side alarm terminal 178, if an alarm signal is received from battery pack 10. Thereby, power FET64 in main part 52 is turned off, and an electric power supply from battery pack 10 to motor 60 is stopped. At this time, main controller 150 makes display for indication 130 corresponding to battery pack 10 which outputted an alarm signal turn on, and reports to a user that battery pack 10 needs exchange or charging. Here, when discharge current from battery pack 10 is detected even after outputting an alarm signal, main controller 150 turns off power FET162 in adapter 100, and opens electric power supply circuit 160 electrically (cutting). Main controller 150 can also be considered as composition which turns off power FET162, without outputting an alarm signal to main part 52 of a power tool. According to this composition, main part 52 of a power tool does not necessarily need to be provided with alarm terminal 78.</p><p>Cutoff switch 132 is formed between main controller 150 and battery side alarm terminal 118. Cutoff switch 132 is turned on/turned off by main controller 150. Main controller 150 turns off cutoff switch 132, when a power tool is not used [predetermined time]. Thereby, electric discharge of battery pack 10 by leak current is forbidden, and fault electric discharge of battery pack 10 is prevented. Main controller 150 stops operation of power supply circuit 152, and also stops own operation.</p><p>Between one battery side alarm terminal 118 and main controller 150, lowered-the pressure type level shifter 136 and 昇 pressure type level shifter 138 are provided. This is because reference voltage (voltage of cathode output terminal 34 of battery pack 10 located up in Drawing 4) of battery pack 10 located in the high-pressure side and reference voltage of main controller 150 are mutually different as a result of connecting two battery packs 10 in series. Then, lowered-the pressure type level shifter 136 changes an alarm signal which battery pack 10 outputs into a voltage level which suits main controller 150. On the other hand, 昇 pressure type level shifter 138 changes an alarm release signal which main controller 150 outputs into a voltage level which suits battery controller 22. Thereby, a signal can be correctly delivered also between main controller 150 which differs in reference voltage mutually, and battery controller 22. On the other hand to battery pack 10 located in the low-pressure side, this kind of level shifter is not needed. Like this example, main controller 150 is connectable with battery side alarm terminal 118 via transistors 140 and 142.</p><p>Main controller 150 is electrically connected to tool side alarm terminal 178. Main controller 150 will output an alarm signal to main part 52 of a power tool from tool side alarm terminal 178, if an alarm signal is received from battery pack 10. By main part 52 of a power tool, as explained previously, if an alarm signal is outputted from adapter 100, power FET64 will be turned off and a drive of motor 60 will be forbidden. Main controller 150 can also receive an alarm release signal from main part 52 of a power tool with tool side alarm terminal 178. Main controller 150 will output an alarm release signal to battery pack 10 from battery side alarm terminal 118, if an alarm release signal from main part 52 of a power tool is received.</p><p>Adapter 100 is further provided with two voltage measuring parts 134. It is connected to anode input terminal 112 and cathode input terminal 114 which are arranged at one battery accession department 106a, and one voltage measuring part 134 can measure output voltage of battery pack 10 attached to one battery accession department 106a. Here, reference voltage of battery pack 10 (battery pack 10 located up in Drawing 4) located in the high-pressure side is the voltage which can set cathode output terminal 34 of the battery pack 10 concerned, and differs from reference voltage of main controller 150. Therefore, voltage measuring part 134 cannot measure output voltage of battery pack 10 directly. Therefore, voltage measuring part 134 (what is located up in Drawing 4) performs a level shift using a differential circuit, and while measuring battery pack 10 located in the high-pressure side measures output voltage of the battery pack 10 concerned. It is connected to anode input terminal 112 and cathode input terminal 114 which are arranged at battery accession department 106a of another side, and voltage measuring part 134 of another side can measure output voltage of battery pack 10 attached to battery accession department 106a of another side.</p><p>A measurement value by each voltage measuring part 134 is inputted into main controller 150. A measurement value by voltage measuring part 134 corresponds to a charge level of battery pack 10. Main controller 150 outputs an alarm signal to main part 52 of a power tool from tool side alarm terminal 178, when a measurement value by voltage measuring part 134 of at least 1 side separates from tolerance level memorized beforehand (when specifically less than an acceptable value memorized beforehand). Thereby, power FET64 in main part 52 is turned off, and an electric power supply from battery pack 10 to motor 60 is stopped. At this time, a measurement value makes display for indication 130 corresponding to battery pack 10 which became unusual turn on, and main controller 150 reports to a user that battery pack 10 needs exchange or charging. Here, when discharge current from battery pack 10 is detected even after outputting an alarm signal, main controller 150 turns off power FET162 in adapter 100, and opens electric power supply circuit 160 electrically (cutting). Main controller 150 can also be considered as composition which turns off power FET162, without outputting an alarm signal to main part 52 of a power tool. According to this composition, main part 52 of a power tool does not necessarily need to be provided with alarm terminal 78.</p><p>As mentioned above, adapter 100 can stop electric discharge of battery pack 10 according to an alarm signal which battery pack 10 outputs. Even when an alarm signal is not outputted from battery pack 10, electric discharge of battery pack 10 can be stopped according to output voltage and discharge current of battery pack 10 which were measured. Thereby, battery pack 10 can be protected. Even when power FET162 is turned off, electric connection between main controller 150 and battery pack 10 is maintained. That is, even after power FET162 is turned off, main controller 150 can continue operating with electric power from battery pack 10.</p><p>As shown in Drawing 5, in adapter 100, battery pack 12 which does not have not only battery pack 10 but the alarm function to have an alarm function can also be attached to each battery accession department 106a. Even if battery pack 12 does not have an alarm function, adapter 100 is, According to output voltage of battery pack 10, an alarm signal can be outputted to main part 52 of a power tool from tool side alarm terminal 178, power FET64 in main part 52 can be turned off, and an electric power supply from battery pack 12 to main part 52 can be stopped. therefore -- that, as for adapter 100, battery packs 10 and 12 have an alarm function か否か -- irrespective of -- fault electric discharge of battery packs 10 and 12 can be prevented. When battery pack 10 has an alarm function, electric discharge of battery pack 10 can be stopped by suitable timing by using the alarm signal. Battery pack 10 which has an alarm function, and battery pack 12 which does not have an alarm function can also be simultaneously attached to adapter 100.</p><p>When preventing fault electric discharge of battery pack 10, an alarm signal is outputted to main part 52 of a power tool from tool side alarm terminal 178, power FET64 in main part 52 is turned off, and an electric power supply to motor 60 is completely stopped by this example. However, an electric power supply to motor 60 may be partially restricted by not stopping an electric power supply to motor 60 completely, for example, turning on/turning off power FET162 intermittently. Also by this method, fault electric discharge of battery pack 10 can be prevented intentionally.</p><p>Adapter 100 of this example is further provided with two bypass circuits 122. One bypass circuit 122 has electrically connected anode input terminal 112 and cathode input terminal 114 of each other which were provided in one battery accession department 106a. Bypass circuit 122 of another side has electrically connected anode input terminal 112 and cathode input terminal 114 of each other which were provided in battery accession department 106a of another side. Each bypass circuit 122 has resistive element 124 and diode 126. A cathode of diode 126 is connected to anode input terminal 112 via resistive element 124, and an anode of diode 126 is connected to cathode input terminal 114.</p><p>Temporarily, adapter 100 shall not have bypass circuit 122. In this case, even if battery packs 10 and 12 are attached only to one battery accession department 106a, controller 150 cannot receive electric power supplies from those battery packs 10 and 12. In battery accession department 106a are not equipped with whose battery packs 10 and 12, it is because anode input terminal 112 and cathode input terminal 114 of each other are not electrically connected and electric power supply circuit 160 cannot form a closed way to main controller 150. By adapter 100 of this example, anode input terminal 112 and cathode input terminal 114 of each other are electrically connected via bypass circuit 122 to it at battery accession department 106a are not equipped with whose battery packs 10 and 12. Therefore, if battery packs 10 and 12 are attached to at least one battery accession department 106a, main controller 150 can start the operation in response to an electric power supply from battery packs 10 and 12.</p><p>Since bypass circuit 122 has diode 126, in battery accession department 106a equipped with battery packs 10 and 12, the bypass circuit 122 will be in the state where it was intercepted substantially. Therefore, when two battery packs 10 and 12 are attached to adapter 100 and electric power is supplied to motor 60, a high current to motor 60 does not flow through bypass circuit 122. However, when momentary loose connection (what is called chattering) of a terminal arises between battery packs 10 and 12 and adapter 100, current to motor 60 may flow into bypass circuit 122. So, in bypass circuit 122 of this example, resistive element 124 is provided and current which flows into bypass circuit 122 is restricted.</p>

<p>Adapter 200 of Example 2 is explained with reference to Drawing 6, Drawing 7, and Drawing 8. As compared with adapter 100 of Example 1, as for adapter 200 of Example 2, two ID terminals 220, two cutoff switches 232, and two level shifters 236 and 238 are added. A part of program of main controller 150 has been changed. Since it is the same as Example 1 about other composition, overlapping explanation shall be omitted by attaching the same numerals as Example 1.</p><p>One ID terminal 220 is provided in one battery accession department 106a, and ID terminal 220 of another side is provided in battery accession department 106a of another side. ID terminal 220 is electrically connected to main controller 150. Between one ID terminal 220 and main controller 150, two cutoff switches 232 and two level shifters 236 and 238 are provided. A use of these cutoff switches 232 and level shifters 236 and 238 and a function are the same as cutoff switch 132 and level shifters 136 and 138 which were explained in Example 1.</p><p>As shown in Drawing 6, Drawing 7, and Drawing 8, battery packs 14, 16, and 18 which have ID terminal 40 can be attached to adapter 200 of this example. In these battery packs 14, 16, and 18, ID terminal 40 is connected to battery controller 22, and battery controller 22 can output ID information memorized from ID terminal 40. ID terminal 220 of adapter 200 is connected to ID terminal 40 of battery packs 14, 16, and 18, and ID information which battery packs 14, 16, and 18 output is received by main controller 150 of adapter 200. It is distinguished what kind of function battery packs 14, 16, and 18 in which main controller 150 was attached to battery accession department 106a based on received ID information have.</p><p>In Drawing 6, battery pack 14 which has an alarm function to adapter 200 is attached. In this case, main controller 150 can detect that battery pack 14 has an alarm function based on ID information received from battery pack 14. When battery pack 14 has an alarm function, main controller 150 stops an electric power supply to motor 60, only when a measurement value by voltage measuring part 134 is disregarded and an alarm signal of battery pack 14 is received. Main controller 150 outputs an alarm signal to main part 52 of a power tool from tool side alarm terminal 178, and, specifically, turns off power FET64 in main part 52 of a power tool. Here, priority is given to an alarm signal which battery pack 14 outputs over a charge level of battery pack 14 measured by adapter 200. Because, it is because a measurement value in adapter 200 is excelled in accuracy when ways of a measurement value in battery pack 14 are many.</p><p>In Drawing 7, battery pack 16 which does not have an alarm function to adapter 200 is attached. In this case, main controller 150 can detect that battery pack 16 does not have an alarm function based on ID information received from battery pack 16. When battery pack 16 does not have an alarm function, main controller 150 stops an electric power supply to motor 60 like Example 1 according to a measurement value by voltage measuring part 134. Thereby, fault electric discharge of battery pack 16 can be prevented irrespective of existence of an alarm function.</p><p>In Drawing 8, battery pack 18 which has an autostop function to adapter 200 is attached. This battery pack 18 contains power FET44 and shunt resistance 42. Battery controller 22 is supervising a charge level of each battery cell 20 by measuring voltage of each battery cell 20. And when a charge level of at least one battery cell 20 separates from tolerance level, battery controller 22 turns off power FET44 and stops the electric discharge spontaneously. When a current value measured by shunt resistance 42 exceeds a memorized acceptable value, battery controller 22 turns off power FET44 and stops the electric discharge spontaneously. Thus, battery pack 18 measures an own state itself, and a function which stops electric discharge spontaneously is called autostop function.</p><p>Main controller 150 can detect that battery pack 18 has an autostop function based on ID information received from battery pack 18. When battery pack 18 has an autostop function, main controller 150 disregards a measurement value by voltage measuring part 134. That is, priority is given to a stop of spontaneous electric discharge by battery pack 18, and processing which stops electric discharge in adapter 200 is not performed. As a result, fault electric discharge of battery pack 18 is prevented by the autostop function of battery pack 18. Priority is given to an autostop function of battery pack 18 over processing in adapter 200, and electric discharge of battery pack 18 is stopped because of adapter 200 of this example by suitable timing.</p><p>As mentioned above, adapter 200 of this example can distinguish whether it is having it being having an alarm function and an autostop function about battery packs 14, 16, and 18 attached to battery accession department 106a. And when battery pack 14 has an alarm function (refer to Drawing 6), unless an alarm signal is received from battery packs 14, 16, and 18 irrespective of a measurement value by voltage measuring part 134, adapter 200 does not stop an electric power supply to main part 52 of a power tool. When battery pack 16 does not have an alarm function, according to a measurement value by (Drawing 7 Reference) and voltage measuring part 134, adapter 200 stops an electric power supply to main part 52 of a power tool. Therefore, fault electric discharge of battery packs 14 and 16 can be prevented irrespective of existence of an alarm function. However, when battery pack 18 has an autostop function, a measurement value by (Drawing 8 Reference) and voltage measuring part 134 is disregarded, and adapter 200 does not perform processing which stops electric discharge of battery pack 18. It is because a measurement value in adapter 200 is excelled in accuracy when ways of a measurement value in battery pack 18 are many.</p>

<p>Adapter 300 of Example 3 is explained with reference to Drawing 9 and Drawing 10. Adapter 300 of Example 3 is compared with adapter 200 of Example 2, Cutoff switch 132 connected to battery side [two] alarm terminals 118 and those battery side alarm terminals 118, level shifters 136 and 138, and transistors 140 and 142 are removed. A part of program of main controller 150 has been changed. Since it is the same as Examples 1 and 2 about other composition, overlapping explanation shall be omitted by attaching the same numerals as Examples 1 and 2.</p><p>Like adapter 200 of Example 2, adapter 300 of Example 3 has ID terminal 220, and can acquire ID information of battery packs 14, 16, and 18. Therefore, adapter 300 can distinguish at least whether it is having an autostop function about battery packs 14, 16, and 18 attached to battery accession department 106a.</p><p>On the other hand, unlike adapters 100 and 200 of Examples 1 and 2, adapter 300 of Example 3 does not have battery side alarm terminal 118, and cannot receive an alarm signal which battery packs 10 and 14 output. Therefore, main controller 150 of adapter 300 stops an electric power supply to main part 52 of a power tool according to a measurement value by voltage measuring part 134, even when battery packs 10 and 14 have an alarm function. Thereby, even if an alarm signal is unreceivable, adapter 200 can prevent fault electric discharge of battery packs 10 and 14.</p><p>However, as shown in Drawing 9, when battery pack 18 has an autostop function, main controller 150 disregards a measurement value by voltage measuring part 134. That is, adapter 300 does not perform processing which stops electric discharge of battery pack 18, even when a measurement value by voltage measuring part 134 separates from tolerance level. As a result, fault electric discharge of battery pack 18 is prevented by the autostop function of battery pack 18. Priority is given to an autostop function of battery pack 18 over processing in adapter 300, and electric discharge of battery pack 18 is stopped because of adapter 300 of this example by suitable timing.</p><p>As shown in Drawing 10 to it, when battery pack 16 does not have an autostop function, according to a measurement value by voltage measuring part 134, an electric power supply to main part 52 of a power tool is stopped irrespective of existence of an alarm function.</p><p>as mentioned above -- that, as for adapter 300 of this example, battery packs 16 and 18 have an autostop function か否か -- irrespective of -- fault electric discharge of battery packs 16 and 18 can be prevented. About battery pack 18 which has an autostop function, electric discharge of battery pack 18 can be stopped because of suitable timing by giving priority to the autostop function.</p><p>As shown in Drawings 1, 2, and 3, adapters 100, 200, and 300 have the structure where tool side unit 102 and battery side unit 106 were connected by electrical cord 104. However, as shown in Drawing 11, adapters 100, 200, and 300 can also be considered as a cordless type constituted by one housing. In this case, although it is an example, connector area 102a can be formed in the upper surface of a housing, and battery accession department 106a can be formed in the undersurface of a housing.</p>

<p>Power tool 400 of Example 4 is explained with reference to Drawing 12 - Drawing 15. Power tool 400 of this example is equivalent to what unified adapter 100 of Example 1 and main part 52 of a power tool which are shown in Drawing 1 - Drawing 5.</p><p>Power tool 400 is electric ブロワー which uses two battery packs 10 as a power supply. This power tool drives a ventilation fan built in main part 402 according to operation to main switch 404, and blows off air from tip 403a of nozzle 403. Composition of power tool 400 explained in this example is not restricted to electric ブロワー, but can be widely applied to various cordless power tools which use a battery pack as a power supply.</p><p>As shown in Drawings 13 and 14, two battery accession departments 406a are provided in main part 402. Each battery accession department 406a engages with connector area 10a of battery pack 10 removably. Thereby, nominal voltage can attach 18-v battery pack 10 to each battery accession department 406a removably. Two battery packs 10 attached to main part 402 are electrically connected to main part 402, and electric power from two battery packs 10 is supplied to the main part 402 concerned.</p><p>Drawing 15 shows circuit composition of power tool 400. circuit composition of main part 402 of power tool 400 which compares Drawing 4 with Drawing 15 and is clearly shown in Drawing 15 is abbreviation to what unified main part 52 and adapter 100 of a power tool which are shown in Drawing 4 -- it is equal. Therefore, overlapping explanation shall be omitted by giving the same numerals as a corresponding component of Example 1 to each component in Drawing 15.</p><p>According to this power tool 400, according to an alarm signal which battery pack 10 outputs, electric discharge of battery pack 10 can be stopped like adapter 100 of Example 1. Even when an alarm signal is not outputted from battery pack 10, electric discharge of battery pack 10 can be stopped according to output voltage of measured battery pack 10. Therefore, even when battery pack 10 does not have an alarm function, electric discharge of battery pack 10 can be stopped according to output voltage of measured battery pack 10. that, as for power tool 400, battery pack 10 has an alarm function か否か -- irrespective of -- fault electric discharge of battery pack 10 can be prevented.</p>

<p>Power tool 500 of Example 5 is explained with reference to Drawing 16. As compared with power tool 400 of Example 4, as for power tool 500 of this example, two ID terminals 220, two cutoff switches 232, and two level shifters 236 and 238 are added. A part of program of main controller 150 has been changed. In other words, power tool 500 of this example is equivalent to what unified main part 52 of a power tool and adapter 200 of Example 2 which are shown in Drawing 6, Drawing 7, and Drawing 8.</p><p>Drawing 16 shows circuit composition of power tool 500. circuit composition of main part 502 of power tool 500 which compares Drawing 6 with Drawing 16 and is clearly shown in Drawing 16 is abbreviation to what unified main part 52 and adapter 200 of a power tool which are shown in Drawing 6 -- it is equal. Therefore, overlapping explanation shall be omitted by giving the same numerals as a corresponding component of Example 2 to each component in Drawing 16.</p><p>In this power tool 500, main controller 150 as well as adapter 200 of Example 2 can distinguish whether it is having it being having an alarm function and an autostop function about battery pack 14 attached to battery accession department 106a. And when battery pack 14 has an alarm function, unless main controller 150 receives an alarm signal from battery pack 14 irrespective of a measurement value by voltage measuring part 134, main part 502 of power tool 500 does not stop an electric power supply to motor 60. On the other hand, when battery pack 16 does not have an alarm function, according to a measurement value according [main controller 150] to voltage measuring part 134, main part 502 stops an electric power supply to motor 60. However, when battery pack 14 has an autostop function, main controller 150 disregards a measurement value by voltage measuring part 134, and does not perform processing which stops electric discharge of battery pack 14. As a result, priority is given to an autostop function of battery pack 14 over processing in main part 502 of power tool 500, and electric discharge of battery pack 14 is stopped by suitable timing.</p>

<p>Power tool 600 of Example 6 is explained with reference to Drawing 17. Power tool 600 of this example is compared with power tool 500 of Example 5, Cutoff switch 132 connected to battery side [two] alarm terminals 118 and those battery side alarm terminals 118, level shifters 136 and 138, and transistors 140 and 142 are removed. In other words, power tool 600 of this example is equivalent to what unified main part 52 of a power tool and adapter 300 of Example 3 which are shown in Drawing 9 and Drawing 10.</p><p>Drawing 17 shows circuit composition of power tool 600. circuit composition of main part 602 of power tool 600 which compares Drawing 9 with Drawing 17 and is clearly shown in Drawing 17 is abbreviation to what unified main part 52 and adapter 300 of a power tool which are shown in Drawing 9 -- it is equal. Therefore, overlapping explanation shall be omitted by giving the same numerals as a corresponding component of Example 3 to each component in Drawing 17.</p><p>According to this power tool 600, main controller 150 as well as adapter 300 of Example 3 can distinguish whether it is having an autostop function about battery pack 18 attached to battery accession department 106a. And when battery pack 18 has an autostop function, main controller 150 disregards a measurement value by voltage measuring part 134. That is, main controller 150 does not perform processing which stops electric discharge of battery pack 18, even when a measurement value by voltage measuring part 134 separates from tolerance level. As a result, fault electric discharge of battery pack 18 is prevented by the autostop function of battery pack 18. Priority is given to an autostop function of battery pack 18 over processing in main part 602 of power tool 600, and electric discharge of battery pack 18 is stopped because of power tool 600 of this example by suitable timing.</p><p>As mentioned above, although an embodiment of the present invention was described in detail, these are only illustration and do not limit the range of a claim. Modification and a changed thing are variously contained in art given in the range of a claim in an example illustrated above.</p><p>a technical element explained to this specification or a drawing is independent -- it is -- with various kinds of combination, technical usefulness is demonstrated and it is not limited to a claim at the time of application by combination of a statement. Art illustrated on this specification or a drawing has technical usefulness by achieving a plurality of objects simultaneously and achieving one object of them itself.</p>