Printer

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a drive mechanism for a paper feed roller applied to a printer.

【0002】

[Conventional technology]

The mechanism disclosed in Japanese Patent Application Laid-Open No. 1-184174 as a drive mechanism for the paper feed roller provided in the printer uses an operation lever to move a transmission gear that meshes with the drive gear and transmits the driving force to the paper feed roller gear. The operation lever is operated by the carriage that has returned to the paper feed position, and the transmission gear and the paper feed roller gear are engaged to transmit the driving force to the paper feed roller. Is.

【0003】

This type of device has the advantage that the paper can be mechanically fed to the printing unit by simply returning the carriage to the paper feed position, but on the other hand, the carriage is attached to the other end of the operating lever. Depending on the state of contact, the transmission gear and the paper feed roller gear may come into contact with each other more strongly than necessary, which may impair the smooth transmission of the driving force.

【0004】

[Problems to be Solved by the Invention]

The present invention has been made in view of such a problem, and an object of the present invention is to drive a new paper feed roller capable of smoothly driving the paper feed roller regardless of the return operation of the carriage. To provide a mechanism.

【0005】

[Means for solving problems]

That is, in order to achieve the above object, the present invention feeds the paper one by one to the printing unit by the paper feed roller and the paper fed by the recording head carried while traveling in the width direction of the paper. In a printer provided with a carriage for recording and writing and an arm member that displaces a movable gear that meshes with a drive gear so as to engage and disengage from the paper feed roller gear, the movable gear is always separated from the paper feed roller gear via the arm member. An operation of providing an urging member for urging in the direction of urging, and when the carriage returns to the paper feed position, the movable gear is brought into contact with the urging member so as to mesh with the paper feed roller gear and elastically deformed. It is characterized in that the portion is provided on the carriage.

【0006】

[Action]

With this configuration, the deviation of the return of the recording / writing means to the paper feed position and the deviation of these deviations regardless of the return speed are absorbed by the urging member, and the movable gear and the paper feed roller gear are engaged with each other. Is always kept constant to enable smooth transmission of driving force to the paper feed roller.

【0007】

BEST MODE FOR CARRYING OUT THE INVENTION

Therefore, examples of the present invention will be described below. Each of the drawings shows a paper transport device according to an embodiment of the present invention.

【0008】

First, the overall configuration of the printer to which this device is applied will be explained with reference to FIG. 1. The paper feed roller 30 and this paper are provided in the paper feed path 20 from the paper feed unit 10 to the print unit 60. A gate roller 40, a pinch roller 50, and a paper detection sensor 23 that roll by pressure contact with the feed roller 30 are arranged, and a transport roller 81 is provided in the paper discharge path 70 from the printing unit 60 to the paper discharge tray 110. A discharge section 90 including a transport section 80 including a star wheel 82 and a push-down jagged roller 92 that pushes down the center portion of the paper p is provided, and from here to a paper discharge tray 110 arranged at a lower position. It is configured to eject printed paper.

【0009】

The above-mentioned paper feed unit 10 comes into contact with the stacker 11a provided at the bottom of the lower case 11 of the printer main body and the center portion in the width direction of the uppermost paper p stacked and placed on the stacker 11a, and feeds the stacker 11a. It is composed of a paper feed roller 12 that feeds toward 20, and further, as shown in FIG. 2, the paper feed roller 12 extends from the paper feed motor 200 to the gear train 210 and one end and the other end of the paper feed shaft 31. It is driven via the fixed gears 32 and 33, the sun gear 13, the planetary gear 14, and the paper feed roller gear 15 on the paper feed roller shaft 16, and further, by the mechanism described later only when the carriage 61 reaches the paper feed position. The paper feed roller gear 15 and the planetary gear 14 mesh with each other and receive a driving force from the sun gear 13 to rotate.

【0010】

On the other hand, the paper feed roller 30 arranged in the paper feed path 20 rotates in the counter paper feed direction during the period in which the paper feed roller 12 is rotating, and moves the paper p fed by the paper feed roller 12. It is configured to be blocked from the gate roller 40, skewed, and then fed to the printing unit 60 via the pinch roller 50. Further, when the carriage 61 is moved to the paper feed position by a mechanism described later. It is configured to transmit the driving force to the paper feed roller 12.

【0011】

On the other hand, the carriage 61 in the printing unit 60 carries an inkjet recording head 62 and is guided by a part of the guide shaft 63 and the upper frame 120 with a slight gap between the upper surface of the intermediate frame 110. The carriage 61 is configured to travel in the main scanning direction, and is further provided with a function of cutting off or connecting a driving force to the paper feed roller 12 as described later.

【0012】

On the other hand, as shown in FIG. 2, there are six paper ejection portions 80, which are located on the upper side of the paper ejection path 70 in the paper transport direction, and are fixed to two rotating shafts 83 and 84, three by three. Consists of the transport rollers 81 .... and six star wheels 82 .... fixed at both ends of the three shafts 86 so as to face each of these transport rollers 81 .... , The printed paper p is configured to be fed out from the recording head 62 toward the output tray 110 while being held flat.

【0013】

The transport roller gears 83a and 84a fixed to the rotating shafts 83 and 84 of these transport rollers 81 .... mesh with the transmission gear 85a integrated with the roller 85b that rolls in contact with the paper feed roller 30. It is configured to receive rotational driving force from the paper feed roller 30, and these transport rollers 81 rotate at a peripheral speed that is about 12% faster than the peripheral speed of the paper feed roller 30, and apply the required tensile force to the paper p. It is configured to grant.

【0014】

By the way, FIGS. 3 and 4 show the paper feed roller drive mechanism which is the main part of the present invention, and the shaft portion 133 projecting from the inner surface of the side frame 130 of the printer main body is mounted on the paper feed roller shaft 31. A sun gear 13 that meshes with the gear 33 of the above is rotatably attached, and a planetary gear 14 that meshes with the sun gear 13 is pivotally supported on the shaft portion 133, and the planet gear 14 meshes with the sun gear 13 is pivotally supported by the paper feed roller on the paper feed roller shaft 16. An arm 140 that is brought into contact with and separated from the gear 15 is rotatably attached.

【0015】

That is, as shown in FIG. 5A, the arm 140 is planted with two pins 143 and 143 having a spring property on one side thereof, and the coil spring 150 is provided via these pins 143. The coil spring 150 is inserted into the recess 134 provided on the inner surface of the side frame 130, and the other end 152 is formed between the side wall surface 136 of the recess 134 and the protrusion 135 protruding from the other side. By sandwiching the coil spring 150 along the side wall surface 136 of the recess 134, the arm 140 is constantly rotated and urged counterclockwise around the shaft portion 133 by utilizing the elasticity of the coil spring 150. , The pivotally supported planetary gear 14 is configured to be separated from the paper feed roller gear 15.

【0016】

On the other hand, as shown in FIG. 6, the above-mentioned carriage 61 has an operation pin 64 protruding from the side surface of the side frame 130 side to transmit the driving force between the sun gear 13 and the paper feed roller gear 15. It is installed.

【0017】

That is, as shown in FIG. 4, the operation pin 64 is penetrated between the side wall surface 136 of the recess 134 provided on the inner surface of the side frame 130 and the coil spring 150 when the carriage 61 is in the paper feed position. The driving force of the sun gear 13 is transferred to the paper feed roller by bending the 150 to the opposite side of the side wall surface 136 and rotating and displaced the arm 140 clockwise in the figure to engage the planetary gear 14 with the paper feed roller gear 15. It is configured to communicate to the gear 15, for which an oblique guide surface 65 is provided at the tip of the operating pin 64 to facilitate penetration.

【0018】

Reference numeral 144 in FIG. 5 indicates a stopper projecting from the back side of the arm 140 in order to contact the inner surface of the recess 137 provided in the recess 134 and regulate the counterclockwise rotation of the arm 140. ..

【0019】

In the embodiment configured in this way, when the carriage 61 is moved to the paper feed position by the paper feed signal from the host computer or the like, the operation pin 64 protruding from the side surface thereof is shown in FIG. As described above, the coil spring 150 is bent into the gap between the side wall surface 136 of the recess 134 provided in the side frame 130 and the coil spring 150, and the coil spring 150 is bent to the opposite side to the side wall surface 136. The planetary gear 14 that is rotated and pivotally supported is meshed with the paper feed roller gear 15, and the paper feed roller 12 is rotated by the driving force of the sun gear 13, and the top-level paper p laminated on the stacker 11a is printed on the printing unit 60. Send to.

【0020】

The paper p fed in this way is then fed between the paper feed roller 30 rotating in the counter-paper feed direction and the gate roller 40 to prevent its movement, and is skewed to the source of the printing unit 60. Then, tension is applied by the transport roller 81, which is set to have a peripheral speed about 12% faster than the paper feed roller 30, and the star wheel 82, which is pressure-welded on the circumference, to flatten the printed surface. The required record is written on the paper and the paper is discharged to the paper ejection tray 110.

【0021】

Although the present invention has been described above with reference to an embodiment in which a coil spring is used as the urging member, this can be replaced with a leaf spring.

【0022】

[Effect of the invention]

As described above, according to the present invention, an urging member is provided that urges the movable gear in the direction of being separated from the paper feed roller gear at all times via the arm member, and when the carriage returns to the paper feed position, the movable gear Since the carriage is provided with an operating part that abuts on the urging member and elastically deforms so as to mesh with the paper feed roller gear, these errors can be eliminated regardless of the deviation of the paper feed position or the timing of the carriage. It absorbs by the bending of the urging member, and enables smooth transmission of driving force while keeping the meshing of the movable gear and the paper feed roller gear always constant.

[Simple explanation of drawings]

[Figure 1]

It is a side view of the printer provided with the paper feed roller drive mechanism which makes an embodiment of this invention.

[Figure 2]

It is a top view which showed the paper feed / discharge path.

[Fig. 3]

It is a side view which showed the paper feed roller drive mechanism in a non-meshing state.

[Fig. 4]

It is a side view which showed the same above mechanism in the meshed state.

[Fig. 5]

(a) and (b) are a side view and a top view of the arm.

[Fig. 6]

It is the top view which showed the carriage.

[Explanation of symbols]

13 sun gear 14 planetary gears 15 Paper feed roller gear 60 Printing section 61 Carriage 64 Operation pin 140 arm 150 coil spring