Coordinate measuring machine and method for introducing a command to change the measurement mode in this machine

The present invention relates to a dimensional measurement column, particularly a dimensional measurement column composed of a column having a single vertical axis, and a method of inputting a command for switching a measurement mode of such a dimensional measurement column. ..

PROBLEM TO BE SOLVED: To measure vertical dimension columns are often used in a machine shop or an industry for measuring different vertical coordinates of a base material. FIG. 1 schematically shows an example of the dimensional measurement column 1. The illustrated dimensional measurement column has a probe tip 12 mounted on the measurement carriage 11 and brought into contact with the base material 3 to be measured, and a vertical probe tip controlled by a crank 13 that can move the probe tip vertically along the axis z. It includes a moving mechanism (not shown). The vertical movement mechanism can be manual or, depending on the model, electrically driven. The measurement and display system 2 determines the position of the probe chip and displays it on the display. The measurement and display system 2 also applies a force to press the probe tip against the base material 3 to be measured. This measurement and display system uses capacitive, inductive, magnetoresistive, or optical sensor means, eg, having a scale in the housing 10 and a sensor in the control panel 2.

[0003] A normal dimensional measurement column customarily has a housing 10 having a height between 50 cm and 2 meters, and can measure the vertical position of the probe tip 12 with an accuracy of about several microns or less. Has been made. The base material 3 to be measured is placed close to the dimensional measurement pillar 1 so that the probe tip moves in the vertical direction and hits the portion of the base material to be measured whose vertical coordinates are to be measured. The sizing column 1 can be mounted on an air cushion support plate 14 that facilitates horizontal movement. Such sizing columns are described, for example, in US4187612 and US3895356. Such dimensional measuring columns are also commercially available by the Applicant, for example under the names MICRO-HITE® and TESA-HITE®.

[0004] Current dimensional measurement columns are equipped with a normal measurement and display system 2, which, for example, displays the absolute height of a point or the difference between two consecutive measurement points. It is possible to perform measurements in different modes such as. The control button 21 of this measurement and display system enables switching between these measurement modes. Other examples of useful measurement modes are described in US3895356 above.

[0005] As the dimensional measurement column, for example, one capable of measuring the inner diameter of a hole or the outer diameter of a bar is known. To measure such dimensions, two turn-back points are measured continuously, that is, the lowest and highest points of the hole or bar are continuously measured and the height between these two points. It is necessary to calculate the difference.

[0006] There are different systems or methods for determining the limit point of a hole or bar by a single axis sizing column 1. For example, there is a device that allows the probe tip to slide horizontally along the axis x perpendicular to the plane in the figure. By applying pressure vertically along the axis z, the probe tip 12 comes to another point, the highest point, facing the lowest point of the hole. Measurements are made at each of these two points and calculations are made so that the difference determines the diameter and / or center of the hole. However, such mechanical devices are not only costly, but also affect the overall accuracy of the measurement system. Further, the size of the hole to be measured is limited by the maximum width of horizontal movement of the probe tip. Finally, such devices are not well adapted for measuring outer diameters, such as measuring the diameter of bars.

[0007] There are also known systems that can automatically determine the return point (end) of a hole or bar. For this purpose, it is necessary to input a command to the measurement and display system 2 to switch to the return point search mode. This command is generally entered by selecting a crank (not shown) close to the control button 21 or probe tip 12 on the control panel. The base material 3 to be measured or the dimensional measurement column 1 is then moved horizontally by maintaining a holding pressure between the probe tip and the base material, and is closer to the end by overshooting the turnaround point at least once. Try to scan the area. The terminal calculation algorithm determines the vertical coordinates of the turning point, and the acoustic and / or optical signal confirms that the vertical coordinates of this point have been calculated. The automatic turnaround point exploration mode is then deselected and the probe tip is moved to perform a new measurement, eg, to locate the other end of the hole or bar for diameter calculation.

[0008] These conventional systems have so many operations that their use is not intuitive. In addition, to control the vertical position of the probe tip to switch to turnback point exploration mode, the base material 3 to be measured or the crank<u style="single">It is possible to temporarily release 13 operations from the settings in the previous mode.</u>is necessary. Besides, turn off the measurement mode<u style="single">Replacement</u>The equipment cost is high due to the existence of the control button 21 that has only the function to obtain.

[0009] Therefore, an object of the present invention is to provide a method of inputting a command for switching the measurement mode of the vertical dimension measuring column, which does not have these drawbacks, and a dimension measuring column which is improved and easier to use than the conventional dimension measuring column. It is in.

[0010] According to the present invention, these objects are achieved by the method and dimension measuring column having the features described in the corresponding independent claims. Suitable embodiments of these methods and sizing columns are described in the dependent claims.

[0011] In particular, these objectives are methods that allow the command to switch the measurement mode to be placed in the dimension measurement column, so that the mode switching command can be entered simply by utilizing the position of the probe tip. It is achieved by the method described above.

[0012] This method has the advantage that the mode switching is performed by using the position of the probe tip in a special way. This method is different from the method used for measuring the position, and the mode switching is displayed. In this way, the base material 3 to be measured or the height command crank to switch the measurement mode<u style="single">Release 13 operations from the mode settings</u>There is no need. Moreover, no additional control button 21 is needed.

[0013] Preferably, the switching of the measurement mode is for controlling the position of the probe tip.<u style="single">By operating the device carefully and reliably</u>Performed and confirmed by audio and / or visible signal. This ensures that the system prevents the risk of accidentally switching measurement modes, either accidentally or at the will of the user.

[0014] The present invention is based on the observation that the attention of the dimensional measurement column user is focused on the position and orbit of the probe tip 12 at each moment. As a result of the test on the user, the position and orbit of the probe tip are better than those by operating the control panel 2 of the dimensional measurement column.<u style="single">On the basis of</u>It turned out that it was quicker and more intuitive to put in a command to switch the measurement mode.

[0015] According to the preferred features of the present invention, the above-mentioned object further receives a command to switch the measurement mode by pressing the probe tip against the base material to be measured for a time interval longer than a predetermined value. It is achieved by the method described above.

[0016] This feature has the advantage of enabling very quick and intuitive mode switching. That is, when the probe tip is pressed against the base material for a duration longer than a predetermined threshold, the measurement and display system immediately switches the measurement mode. This switching is confirmed by voice and / or visible signal.

[0017] According to a preferred feature of the present invention, the dimensional measuring column allows the force of pressing the probe tip against the base metal to be measured. The command to switch the measurement mode is also preferably the force of this squeeze.<u style="single">To</u>By using it, for example, it is entered by maintaining a constant pressing force for a predetermined time interval.

[0018] Preferably, the switching of the measurement mode is entered by careful handling of the device that controls the position of the probe tip and is confirmed by audio and / or visible signals. This ensures that the system prevents the risk of accidentally switching measurement modes, either accidentally or at the will of the user.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be better understood by the embodiments shown in the accompanying drawings and detailed below.

[0020] The present invention is applicable to manual or motor driven sizing columns having one or several axes, eg, sizing columns of the form illustrated in FIG. 1 and described above. FIG. 2 shows one example of the control panel 2 of the measurement and display system for dimensional measurement columns according to the present invention. The control panel includes a display 20, such as a liquid crystal or plasma display, and some control buttons 21. The measurement and display system 2 can also include other data input means such as, for example, a mouse, joystick, microphone, etc., and a serial interface such as a speaker, printer, RS232 type, infrared type, or wireless type. It is also possible to connect a computer to the measurement and display system 2 or connect it within the network.

[0021] The upper portion 200 of the display 20 can be displayed by a measured value (7-digit number 2000 in this example). This measurement corresponds to, for example, the absolute vertical position of the probe tip, the difference between the two positions, the diameter, etc., depending on the measurement mode selected. Further, it will be described later that this upper portion 2000 of the display 20 is used as a bar graph showing the force of pressing the probe tip against the base material 3 to be measured. Icon 2001 indicates whether the measurement being performed is one probe or two probes, for example in the case of diameter measurement. The icon 2002 indicates the choice of displaying the average or difference between the two probes, for example displaying the center of the hole or the diameter.

[0022] The lower portion 201 of the display indicates the current function of the programmable function key 210 by the icon 2010. The triangular symbol 2011 indicates the increment or travel direction of the variable, or the selected menu.

[0023] The control panel 2 further includes a control button 21 including a programmable function key 210 and a key 211 having a predetermined function such as an on / off button, a print key, and the like.

The measurement and display system follows several distinct measurement modes that can be selected by keys 210, 211, or<u style="single">To the first measurement point in the desired measurement mode</u>By moving the probe tip 12,<u style="single">Alternatively, with respect to some preset measurement modes, such as by repeatedly pressing the probe tip against the base material at a specific position such as the top or bottom of the base material to move to the next set measurement mode.</u>Can function. Possible measurement modes include, for example, the following items. -Coordinate measurements without counting probe constants. This allows a single direction (towards the top or bottom), such as the measurement of a stepped base material.<u style="single">only</u>) Can only be measured. -Dimensional measurements that account for probe constants. This allows measurements in both directions, such as the measurement of hole diameter. -Measurement of inner or outer diameter with exploration of turning point. -Measurement and continuous display of probe tip position. -Measurement of vertical deviation from a straight line. -Measurements along different axes. -Other.

The present invention can also be used with any type of control panel or programmable terminal. However, the illustrated control panel has the advantage of embracing the display and button arrangements already widely used in conventional dimensional measurement columns. This makes it possible to eliminate the cost of developing a new control panel. In addition, users are already accustomed to this type of control panel. Moreover, it is possible to reprogram existing dimensional measuring columns and measuring and displaying systems to use the present invention without making changes to the display and control buttons.

[0026] With reference to FIGS. 3 to 8, the steps performed to determine the turning point of the holes 30 of the base metal will be described. In the following description, the case of determining the lowest point (minimum 300) of the hole 30 in the case of measuring the inner diameter is particularly mentioned. The same or similar steps are performed in determining the highest point (maximum 301) and in determining the outer edge when measuring the outer diameter of the bar.

[0027] In FIG. 3, the probe tip 12 is brought into contact with an arbitrary point on the inner surface of the hole 30 of the base material 3 by moving the crank 13 or moving the base material 3 or the dimension measuring column 1. The display 20 of the measurement and display system immediately enters bar graph mode, indicating the pressing force of the probe tip by the number 2000. This pressing force also<u style="single">Even if the base metal or dimensional measurement column is moved</u>It can be reproduced by controlling the torque of the crank 13.

[0028] The measurement and display system can also detect the direction of the pressing force, which in this example is displayed as a negative value in the bar graph, and in the variant also the probe tip 12 instead of the pressing force. It can be displayed as the position, or the position of the probe tip in addition to the pressing force.

【0029】<u style="single">When the probe tip 12 is brought into contact with an arbitrary point on the inner surface of the hole 30 of the base material 3 by the above operation,</u>Pressing force<u style="single">If you operate to release the</u>, The measurement of the probe point is counted and displayed on display 20. Conversely, if the probe tip 12 is held firmly pressed against the base material 3 as shown in FIG. 5, the measurement and display system will automatically switch modes after a predetermined time, eg 0.5 seconds. Then, the turnaround point search mode is entered. This switching is preferably indicated by a beeping sound and by changing the display board of the display 20. In the example shown in FIG. 6, the icon 2002 indicates that the coordinates of the center of the hole are determined.

[0030] In order to determine the lowest point 300 of the hole 30, the pressing force between the probe tip 12 and the base material is controlled by the crank 13, so that the base material 3 to be measured or the dimension measurement column 1 is horizontal. The region near the end is scanned by moving in the direction and passing the turnaround point 300 (FIG. 7) at least once. The display 20 shown in FIG. 8 continuously shows the pressing force between the probe tip 12 and the base metal 3. This turning point<u style="single">For the measurement of (in this case, the lowest point of the hole 300), when the pressing force is changed beyond the predetermined allowable range, the measurement of the turning point is automatically terminated.</u>Graphically instructed on display 20. In this case, the measurement and display system<u style="single">Early</u>Measurement mode<u style="single">That is, the probe tip is brought into contact with another point in the hole 30, such as the upper end, to enter a new turning point measurement mode.</u>。

[0031] The dimension measurement pillar is predetermined.<u style="single">Tolerance</u>As long as the pressing force inside is applied to the base material under test by the probe tip, it remains in the turning point search mode. The measurement and display system determines the trajectory followed by the probe tip during this mode. The end calculation algorithm automatically determines the vertical coordinates of the lowest point (turnback point 300) of this orbit. In this case, interpolation, two nearest end would possibly be executed between the end measuring point. An acoustic signal (a beep) and / or an optical signal 2011 is emitted as soon as the terminal value is found. For more accurate measurements, the area near the turn-back point 300 is continuously scanned several times in the opposite direction. In this case the terminal measurement points are taken into account. Without the user releasing the pressing force<u style="single">Use the probe tip in the turnaround point search mode</u>If you turn back in the opposite direction several times,<u style="single">The lowest point of the orbit is measured each time. When the pressing force is released, the probe tip separates from the inner wall of the hole 30 and its vertical position shifts out of the predetermined interval. Therefore,</u>The measured turn-back point is valid only when the vertical positions of several measurements are within a predetermined interval.

[0032] When an unfamiliar careless user moves the probe tip toward the lowest point of the hole and turns it back before reaching the lowest point 300, the end is composed of this turning point, and the hole It will be different from the lowest point of 300. To eliminate such inaccurate measurements, turnback point measurements are preferably made on the probe tip.<u style="single">Derivative of vertical change with respect to orbital change, i.e. derivative</u>When is zero at the end<u style="single">That is, when the vertical position does not change</u>Make it valid only.

As soon as the terminal 300 is found, the user releases the probe tip 12 to activate the measurements made and pull the probe tip away from the base material 3. The measurement and display system 2 reacts to reduce the pressing force by immediately stopping the turn-back point exploration mode and displaying, for example, the calculated turn-back point coordinates.

To measure the diameter and / or coordinates of the center 302 of the hole 30, a similar exploration operation is performed by moving the probe tip 12 relative to the upper portion of the hole 30 and again finding the upper end 301 of the hole 30. To start. The measurement and display system is programmed to display either the center 302 of the hole 30 (the average value between positions 300 and 301) or the diameter (difference between these values).

For a base metal that can be found without exploration of the other end, as in the case of a hole or, for example, a semicircular hole, the vertical coordinates of this other point are measured directly and then between the two ends. It is possible to display the distance of. It is also possible to mix two geometrically shaped probes with turning back in the same direction for the same measurement.

[0036] The methods of the invention are preferably used in a newly designed measurement and display system 2 or in a novel command program for a measurement and display system. In this way, a new dimensional measurement column, or a new measurement and display system 2, or the form of an electronic card in the form of, for example, a magnetic disk, optical disc or EEPROM or flash, is designed to be loaded during the current dimensional measurement. It is possible to commercialize it in any form of a commercially available computer program by putting it in a computer data medium of the intended meaning.

Although the above description specifically mentions the specific case of a single vertical axis dimensioning column, the present invention also refers to a dimensioning column (coordinate measurement system) in which the probe tip can move along several axes. Can be applied to. In this case, the mode switching command can also be entered by moving the probe tip along any axis or a combination of multiple axes.

[0038] Further, it is possible to input another command for switching the measurement mode by moving the probe chip 12. Therefore, the probe tip is placed in a holding position, such as the top of a dimensional measuring column.<u style="single">Put</u>、<u style="single">Place the probe tip at the first measurement point in the desired measurement mode, or repeatedly press the probe tip against the base metal at specific locations such as the top or bottom of the base metal.</u>Dimension measurement by guiding the probe tip to a specific trajectory and / or increasing the pressing force<u style="single">mode</u>Can be reset or modified. It is also conceivable to enter the display mode command in order to select the display language or the measurement unit by, for example, the crank 13.

[0039] Preferably, the measurement mode is switched by the handling operation of the crank 13 for controlling the position of the probe tip. This ensures that the system switching measurement modes prevents the risk of sudden operation regardless of the user's will. However, some mode switching is commanded in connection with the movement of the probe tip due to normal measurements. For example, it can be considered that the measurement accuracy and / or the resolution is changed according to the speed of movement of the probe tip.

BRIEF DESCRIPTION OF THE DRAWINGS [FIG. 1] FIG. 1 is a schematic side view of an embodiment of a dimensional measurement column to which the present invention is applied.

FIG. 2 is a front view of a control panel of a measurement and display system.

FIG. 3 is an elevational view of a base material having a circular hole for which diameter is to be measured and a base material showing the position of the probe tip at the start of turnback point exploration.

FIG. 4 is a front view of the control panel showing the display state of the control panel at the start of the turnaround point search.

FIG. 5 is an elevational view of the base metal showing the base metal and the position of the probe tip in the next stage of turnback point exploration.

FIG. 6 is a front view of the control panel showing the display state of the control panel in the next stage of the turning point exploration.

FIG. 7 is an elevational view of the base material showing the position of the probe tip when the base material and the turning point have been manipulated.

FIG. 8 is a front view of the control panel showing a display state of the control panel when the base material and the turning point have been operated.

[Code description] 1 Dimension measurement pillar 2 Measurement and display system 3 Measurement base material 10 Housing 11 Measurement carriage 12 Probe tip 13 Crank 14 Air cushion support plate 20 Display 21 Control button 200 Upper part 201 Lower part 210 Programmable function key 211 Key 2000 Number 2001 Icon 2002 Icon 2010 Icon 2011 Triangle Symbol 30 Base Material 300 Lowest Point 301 Highest Point 302 Center