JPS5938116B2 - paper feed mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper feeding mechanism for a small printer that feeds paper intermittently.

An object of the present invention is to enable special paper feeding (rapid paper feeding) compared to normal paper feeding by changing the rotation ratio between the driving wheels.

Another object of the present invention is to reduce drive noise by meshing gears between the drive wheels. Still other objects of the present invention are that the precision of parts can be easily achieved, the structure is simple and easy to assemble, the size and power can be easily reduced, and the cost can be reduced. Various methods have been considered for intermittent paper feeding in conventional small printers, including a plunger method, a cam and link method, and a clutch method. In this case, the method using a plunger has a simple structure, but since the plunger must be operated several times to rapidly feed the paper, the plunger becomes large, expensive, and requires a large current. In addition, methods using clutches, cams, and links have a complicated structure, generate relatively loud drive noise, and must be operated several times for the amount of rapid paper feed.Furthermore, the operation control circuit is complex, and the number of operations is proportional to the number of operations. This inevitably increases the operating time, which is not desirable in terms of commercial value. The present invention eliminates or improves such drawbacks, and consists of a drive wheel and drive wheel that transmits rotation to the paper feed roller by sliding the drive wheel back and forth in the thrust direction using a sliding means. By changing the rotation ratio with the wheel, it is possible to easily feed paper faster than normal paper feeding.

An overview diagram of one embodiment of the present invention is shown in FIG. 1, and operation diagrams are shown in FIGS. 2, 3, and 4. A transmission driving gear 2 is wedged on the transmission driving shaft 1, and the transmission driving shaft 1 is connected to a motor and rotates in the direction of arrow 101.

The driving shaft 3 has a driving gear part 5 that meshes with the transmission driving gear 2, a normal paper feed tooth part 6 provided on a part of the circumference, and a paper fast feed tooth part 7 provided in a part of the circumference. , a drive gear 4 having an arcuate cam portion 8 provided on another part of the same circumference where the normal paper feed tooth portion 6 and the paper fast feed tooth portion 7 are provided is pivotally attached to be slidable in the thrust direction as shown by the arrow 102. The driving gear 4 receives an acting force 105 in the thrust direction due to the energy stored in the sliding spring 10 supported by the rapid traverse spring support pin 9 fixed to the driving shaft 3, and the driving shaft It is supported on a surface by a sliding lever 11 which is pivotally attached to 3 so as to be slidable in the thrust direction. The driven shaft 12 has a paper feed tooth groove portion 14 that meshes with the normal paper feed tooth portion 6 during normal paper feeding and meshes with the normal paper feed tooth portion 6 and the paper fast feed tooth portion 7 during fast feed of paper, and a paper feed tooth groove portion 14 that meshes with the normal paper feed tooth portion 6 and the paper fast feed tooth portion 7 when paper is rapidly fed. A driven gear 13 is wedged to the driven shaft 12 and has locking teeth 15 that lightly touch the arcuate cam part 8 to lock the paper when the paper feed is stopped. The paper feed roller 16, which receives the pressure of 1 and transports the printing paper 18 in the direction of arrow 104 by the frictional force with the paper presser roller 17, is wedged. Next, the operation from the direction of arrow A in FIG. 1 will be described with reference to FIGS. 2, 3, and 4.

FIG. 2 is an operational diagram when paper feeding is stopped.

Normally, the paper feed tooth portion 6 and the paper fast feed tooth portion 7 are the paper feed tooth groove portion 1.
4, the paper feeding is completed, and the locking tooth portion 15 is in slight contact with the circular arc cam portion 8, so that the driving gear 4 moves toward the arrow 102.
Even if the driven gear 13 rotates in this direction, the driven gear 13 remains locked until the next paper feed. By locking the driven gear 13, the rotation of the paper feed roller 16 is completely stopped. Therefore, printing paper 1
8 guarantees reliable transportation without unevenness. FIG. 3 shows the operation during normal paper feeding, in which the driving gear 4 in FIG. Only the tooth portion 6 is in a position where it can mesh with the paper feed tooth groove portion 14. Therefore, the driven gear 13 rotates in the direction of the arrow 102, and the normal paper feed tooth section 6 meshes with the paper feed tooth groove section 14, so that the
It starts rotating in the 03 direction. When it rotates further, the locking tooth portion 15 is locked by the circular arc cam portion 8, and the rotation is stopped. Therefore, the printing paper 18 is normally transported by the distance of the paper feed dog section 6 and then stopped. Next, FIG. 4 shows the operation during fast-forwarding of paper, in which the sliding lever 11 in FIG. Gear 4 in thrust direction 1
07, the normal paper feed tooth portion 6 and the paper fast feed tooth portion 7 are in a position where they can mesh with the paper feed tooth groove portion 14.

Similarly to the explanation in FIG. 2, the driven gear 13 normally starts to rotate in the direction of arrow 103 when the paper feed tooth portion 6 meshes with the paper feed tooth groove portion 14, and when it rotates further, the locking tooth portion is moved by the arcuate cam 8. 15 is locked, the paper fast-feeding tooth section 7 begins to engage with the next paper-feeding tooth groove section 14 and further rotates in the direction of the arrow 103, after which it is locked.

That is, by meshing the paper fast-feeding tooth portion 7 and the paper-feeding tooth groove portion 14, the driven gear 13 is moved by an amount corresponding to the paper fast-feeding tooth portion 7.
The rotation ratio between the drive gear 4 and the drive gear 4 changes, and the printing paper 18 is rapidly fed. Further, the driving gear 4 is in the thrust direction 10
7, the locking tooth portion 15 lightly touches the arcuate cam portion 8 and slides while being locked, so that the paper feed roller 16 remains stopped, ensuring reliable paper feed without unevenness. Next, when the external force 106 applied to the sliding lever 11 manually or by a prime mover is removed, the sliding lever 11 and the driving gear 4 slide back to their original positions due to the acting force 105 in the thrust direction of the sliding spring 10. , the paper fast-feeding tooth portion 7 does not mesh with the paper-feeding tooth groove portion 14, and only the normal paper feeding tooth portion 6 returns to the position where it can mesh with it.

As described above, according to the present invention, during normal paper feeding, the paper is fed by the normal paper feeding tooth section 6, and when the paper is rapidly fed, the driving gear 4 is slid in the thrust direction 107 by the sliding lever 11. By moving the paper fast-feeding tooth portion 7 into engagement with the paper-feeding tooth groove portion 14 and changing the rotation ratio between the driven gear 13 and the driving gear 4, normal paper feeding and fast paper feeding can be easily made possible. .

Furthermore, driven gear 13 and driving gear 4 mesh with each other to reduce drive noise, and the structure can be simplified, making it easier to achieve component accuracy, fewer parts, ease of assembly, and miniaturization. , the power can be easily reduced and the cost can be further reduced, so the effect is great. In the present invention, the normal paper feed tooth section 6 provided on the drive gear 4 has one tooth, the paper fast feed tooth section 7 has two teeth, and the driven gear 13
Although the driving gear 4 is provided with an arcuate cam portion 8 and the driven gear 13 is provided with a locking tooth portion 15 in order to lock the cam, the number of teeth, the shape of the teeth, and the shape of the cam are not restricted. Further, although the sliding lever 11 and the sliding spring 10 are used as sliding means, the method and form of the means for sliding the driving gear 4 back and forth in the thrust direction are not restricted. Furthermore, although it was decided to change the rotation ratio with the driven gear 13 by sliding the driving gear 4 back and forth in the thrust direction, the rotation ratio with the driving gear 4 can be changed by sliding the driven gear 13 back and forth in the thrust direction. Even if the effect is changed, the effect will be the same and will not be hindered. Next, FIG. 5 shows an overview of another embodiment of the present invention, and FIG. 6, as shown in Figures 7 and 8.

A slip driving gear 22 is wedged on the transmission driving shaft 21, and the transmission driving shaft 21 is connected to a motor and rotates in the direction of arrow 201.

The driving shaft 23 includes a driving gear part 25 that meshes with the transmission driving gear 22, a cylindrical cam part 26 having tooth groove parts 39 and 40 on a part of the circumference, and a part on the circumference corresponding to the tooth groove part 39. A driving gear 2 having a normal paper feed tooth portion 27 provided at a portion thereof and a paper fast feed tooth portion 28 provided at a portion on the circumference corresponding to a tooth groove portion 40.
4 is pivoted so as to be slidable in the thrust direction and rotates in the direction of arrow 202, and is driven by the energy stored in the sliding spring 30 supported by the fast forward spring support pin 29 fixed to the driving shaft 23. 24 receives an acting force 205 in the thrust direction and is supported on a sliding lever 31 which is pivotally attached to the driving shaft 23 so as to be slidable in the thrust direction. Driven shaft 3
2 includes a paper feed tooth portion 34 that meshes with the normal paper feed tooth portion 27 during normal paper feed and meshes with the normal paper feed tooth portion 27 and the paper fast feed tooth portion 28 during fast feed of paper, and a Groove 3
A paper feed auxiliary tooth portion 35 is provided so as to mesh with the tooth grooves 39 and 40 during rapid paper feed, and to lightly contact the outer circumference of the cylindrical cam portion 26 after paper feed is completed and when paper feed is stopped.
A driven gear 33 in which
Furthermore, the driven shaft 32 receives pressure from the paper press roller 37 and moves the printing paper 38 at the arrow 2 by the frictional force with the paper press roller 37.
A paper feed roller 36 that transports the paper in the 04 direction is wedged. Figure 6 is a diagram of the operation after paper feeding is completed and when paper feeding is stopped, Figure 7 is a diagram of the operation during normal paper feeding, and Figure 8 is a diagram of the operation when paper is rapidly fed. When rapidly feeding the paper, the driving gear 24 is slid back and forth in the thrust direction by the sliding spring 30 and the sliding lever 31, and the rotation ratio between the driving gear 24 and the driven gear 33 is changed. This is an embodiment according to the present invention, the first, second, third, and fourth embodiments of the present invention.
It is the same as the figure, and the tooth profile shape, cam shape, etc. are the first, second,
Although it is different from FIGS. 3 and 4, its operation, effect, and action are the same.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an embodiment according to the present invention, in which 3 is a driving shaft, 4 is a driving gear, 6 is a normal paper feed tooth section, 7 is a paper fast feed tooth section, 8 is an arcuate cam section, and 10 is a sliding gear. 11 is a sliding lever, 12 is a driven shaft, 13 is a driven gear, 14 is a paper feeding tooth groove, 15 is a locking tooth, 16 is a paper feeding roller, 17 is a paper pressing roller, and 18 is printing paper. . Figure 2 is an operation diagram when paper feeding is stopped in Figure 1, Figure 3 is an operation diagram during normal paper feeding in Figure 1, and Figure 4 is an operation diagram when paper is rapidly fed in Figure 1. . FIG. 5 is an overview diagram of another embodiment according to the present invention, in which 23 is a driving shaft;
4 is a driving gear, 26 is a cylindrical cam portion provided with tooth groove portions 39 and 40, 27 is a normal paper feed tooth portion, 28 is a paper fast feed tooth portion, 3
0 is a sliding spring, 31 is a sliding lever, 32 is a driven shaft, 33
34 is a driven gear, 34 is a paper feed tooth portion, 35 is a paper feed auxiliary tooth portion, 36 is a paper feed roller, 37 is a paper pressing roller, and 38 is a printing paper. Figure 6 is an operation diagram when paper feeding is stopped in Figure 5, Figure 7 is an operation diagram during normal paper feeding in Figure 5, and Figure 8 is an operation diagram when paper is rapidly fed in Figure 5. .

Claims (1)

[Claims] 1. A paper feeding device for a small printer that feeds printing paper intermittently, the paper feeding roller comprising a paper feeding roller and a paper pressing roller positioned to sandwich the printing paper, and at least one type of tooth or cam. a driven wheel that transmits rotation to the driven wheel; teeth or cams that engage the teeth or cams of the driven wheel in a first thrust position to feed the printing paper a predetermined amount; and teeth or cams of the driven wheel in a second thrust position; teeth or cams that engage with the teeth or cams to feed the printed paper by an integral multiple of the predetermined amount; and teeth or cams that engage with the teeth or cams of the driven wheel except when feeding the printed paper, and the driven wheels a driving wheel including an arcuate cam for positioning the car; and manually sliding the driving wheel or the driven wheel to the second thrust position when the driven wheel is positioned by the arcuate cam. A paper feeding mechanism for a small printer, characterized by comprising a sliding means.