JPH0347775A - Printer - Google Patents

Abstract

PURPOSE:To obtain a printer having no possibility of catching paper by a printing head by a method wherein a power is changed over so as to be transmitted to a head moving mechanism part in conducting a printing action, and the power is changed over so as not to be transmitted to the head moving mechanism part in inserting paper or continuously feeding paper. CONSTITUTION:The power of a motor is transmitted from a motor gear 1 to a reduction gear 3 to be divided into two powers. One is transmitted to a paper feed gear 4 to conduct a paper feed action. The other is transmitted to a head moving gear 5 to reciprocate a printing head 100 longitudinally to make a printable state. When paper is to be inserted or continuously fed, a movable iron core 9a of a solenoid 9 is attracted, and a step-up gear 8 mounted on a lever 7 is rotated to be disengaged from the head moving gear 5. Then, the power of the motor is transmitted from the motor gear 1 to the paper feed gear 4 to allow a paper feed action, but is not transmitted to the head moving gear 5 to avoid the reciprocation of the printing head 100.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer having a mechanism for preventing paper jams.

[Conventional technology]

Traditional methods to prevent paper jams in printers include:
As shown in FIG. 7, an elastic member 102 is installed in front of the print head 1000 at the outlet of the paper guide to prevent the paper 101 from floating at the tip of the print head 100, or as shown in FIG. Paper 10 that was fed when the paper was pressed at the exit of the printer case or the opening was blocked.
There is a method of absorbing the slack by providing a space 103 between the paper outlet of the printer and the printer case so that the slack does not reach the tip of the print head 100.

[Problems and Objectives to be Solved by the Invention] However, in the above two prior art techniques, when continuously feeding paper and inserting paper, the print head always makes reciprocating motion perpendicular to the direction in which the paper travels. I was going. In the above structure in which an elastic member is provided in front of the print head at the outlet of the paper guide, the leading edge of the paper may float when the paper is inserted, and the leading edge of the print head may catch the paper, causing a paper jam or preventing the continuous feeding of the paper. If the paper exit section is blocked by a hand or the like, the paper may sag at the print head section and the print head tip may catch the paper side end surface, causing a paper jam.

In addition, in the configuration described later in which a space is provided between the print head and the paper exit section, the leading edge of the paper may float when the paper is inserted and the leading edge of the printing section may catch the paper, causing a paper jam or paper jam. If the paper outlet section is blocked by a hand or the like during continuous feeding, and the paper sag more than the sag of the paper equivalent to the space above, the sag will sag at the print head, and the tip of the print head will touch the edge of the paper as described above. The problem with the hook was that it caused a paper jam.

SUMMARY OF THE INVENTION Therefore, in order to solve these conventional problems, it is an object of the present invention to provide a printer in which the print head does not catch paper when inserting paper or continuously feeding paper.

[Means to solve the problem]

The printer of the present invention includes a motor that generates power based on an electric signal, a paper feed transmission means that transmits the power of the motor to a paper feed shaft, a paper feed roller that serves to feed printed paper, and a paper feed gear shaft that transmits the power of the motor to a paper feed shaft. A clutch mechanism that serves to selectively transmit the transmitted power to the paper feed roller, a head feeder that reciprocates the printing means, and a function that selectively transmits the power from the motor to the head feeder. and a switching means.

[Effect]

In the printer configured as described above, when performing a normal printing operation, the switching means switches so that the power of the motor is transmitted to the head feeding mechanism. At this time, when the motor is driven, the print head reciprocates from side to side to enable printing. When inserting paper or continuously feeding paper, the switching means switches the motor power so that it is not transmitted to the head feed 8M structure. At this time, even if the motor is driven, the head does not reciprocate from side to side, and even if the paper sag when the paper is inserted or when the paper is continuously fed, there is no paper jam caused by the paper being caught at the tip of the print head.

[Embodiment 1] An embodiment of the printer of the present invention will be described below based on the drawings. FIG. 1 is a side view of the printer of the present invention. 1
3 is a reduction gear that divides the motor power transmitted through the motor reduction gear 2 into two parts; 4 is a paper feed roller (not shown); and 4 is a paper feed roller (not shown). A paper feed gear is fixed to a paper feed shaft 4a having an engaged spring clutch mechanism and a trigger mechanism, and 5 is a head feed camshaft 5a having a cylindrical cam (not shown) on the same axis and a print head engaged in a cam groove. The head feed dog L 7 fixed to the head feed gear L 7 is rotatable around a transfer gear shaft 6 a which is a fulcrum of the transfer gear 6 in the middle of the gear train that transmits the power of the motor to the head feed gear 5 , and is always connected to the transfer gear 6 . A lever 9 is rotatably mounted with a speed increasing gear 8 that can mesh with the head feed gear 5. The lever 9 attracts and repulses the movable iron core 9a engaged with the hole at the tip of the lever 7 by electric signals. A bistable solenoid 10 is a spring that applies force to the lever 7 so that the speed increasing gear 8 attached to the lever 7 meshes with the head feed gear 5.

Next, the operation of the present invention will be explained. FIG. 1 is a side view showing a state in which the printer according to the present invention can print. Here, the solenoid 9 is in a state of repulsion due to the electric signal, and the speed increasing gear 8 is engaged with the head feed gear 5 by the spring 10.

At this time, the power of the motor generated by the electric signal is transmitted from the motor gear 1 to the reduction gear 3 via the motor reduction gear 2. This reduction gear 3 divides the power into two parts, one of which is transmitted to the paper feed gear 4 on the paper feed shaft. Paper feed shaft 4
The paper feed operation is performed by operating the trigger mechanism on a. The other is transmitted to the head feed gear 5 on the head feed camshaft 5a. When the cylindrical cam is rotated by the power of the motor, the print head 100 engaged with a cam groove of a cylindrical cam provided coaxially with the head feed camshaft 5a performs a left-right reciprocating motion, thereby enabling printing.

FIG. 2 is a side view showing a state in which paper can be inserted and paper can be continuously fed by the printer according to the present invention.

At this point, the solenoid 9 is in the attracted state due to the electrical signal. When the movable core 9a of the solenoid 9 overcomes the force of the spring IO and is attracted, the lever 7 engaged with the movable core 9a rotates about the transmission gear shaft 6a as a fulcrum. At this time, the speed increasing gear 8 attached to the lever 7 also rotates, and the meshing with the head feed gear 5 is released. At this time, the power of the motor generated by the electric signal is transmitted from the motor gear 1 to the paper feed gear 4 via the reduction gear 3, and paper feeding becomes possible by operating the trigger mechanism. Power is not transmitted and the print head 100 does not reciprocate from side to side.

In the embodiments described above, when paper is inserted, the leading edge of the paper lifts up, or when paper is continuously fed, paper sag occurs due to paper being pressed at the paper exit section, and the paper is caught at the leading edge of the print head, resulting in a paper jam. By sucking the solenoid 9 and not operating the print head 100 when there is a high possibility that a paper jam will occur, it is possible to prevent a paper jam when one person inserts paper or when paper is continuously fed.

[Example 2] Another embodiment of the printer will be explained based on the drawings.

FIG. 3 is a side view of the printer of the present invention. Figure 4 (a
) to (C) are diagrams showing the switching mechanism section of the printer of the present invention. 1 is a motor gear, 3 is a reduction gear, 4 is a paper feed gear, 5 is a head feed gear, and 50 is a cylinder having a cam groove for engaging and reciprocating the print head 100 and coaxial with the head feed gear shaft 5a. 52 is a head feed ratchet that is coaxial with the head feed gear shaft 5a; 55 is a head feed that engages with the head feed cam 50 at one end and the head feed ratchet 52 at the other end for integral operation; A coiled head feed clutch spring is tightly wound around the gear shaft 5a, 51 is a head feed trigger plate that can be engaged with a head feed ratchet 52 by an electric signal to a coil 53 around a fulcrum 56, and 54 is a head feed trigger. This is a trigger spring that biases the plate 51 in a direction that does not engage the head feed ratchet 52.

Next, the operation of the present invention will be explained. FIG. 4(b) is a diagram showing a state in which the printer according to the present invention can print using solid lines. At this time, the electric signal of the coil 53 is in an OFF state, and the head feed trigger plate 51 and the head feed ratchet 52 are not engaged by the trigger spring 54. In FIG. 3, at this time, the motor power generated by the electric signal in the direction of the arrow is transmitted from the motor gear 1 to the reduction gear 3 via the motor reduction gear 2. This reduction gear 3 divides the power into two parts, one of which is transmitted to the paper feed gear 4 on the paper feed shaft. A paper feeding operation is performed by operating a trigger mechanism on the paper feeding shaft 4a. The other is transmitted to the head feed gear 5 on the head feed camshaft 5a and rotates in the direction of the arrow. This power is shown in Figures 4(a) to (C
), it is transmitted to the head feed cam 50 by the action of the head feed clutch spring 55. When the cylindrical cam is rotated by the power of the motor, the print head 100 engaged with the cam groove of the cylindrical head feed cam 50 performs a left-right reciprocating motion, and is capable of printing.

FIG. 4(b) is a diagram showing, by broken lines, a state in which the printer according to the present invention is capable of inserting paper and continuously feeding the paper.

At this time, the electric signal of the coil 53 is on, overcoming the trigger spring 54, and the head feed trigger plate 51 and head feed ratchet 52 are engaged. At this time,
The power of the motor generated by the electric signal is transmitted to the head feed gear 5, and the head feed gear shaft 5a rotates in the direction of the arrow shown in FIGS. 4(a) and 4(c). The head feed clutch spring 55 attempts to rotate together with the head feed gear shaft 5a, but the head feed ratchet 52, which is engaged with the slack side of the head feed clutch spring 55, is stopped with respect to the head feed gear shaft 5a. Therefore, the head feed clutch spring 55 begins to loosen from the head feed cam 50 side, and the rotation of the head feed gear shaft 5a is not transmitted to the head feed cam 50. At this time, the power of the motor generated by the electric signal is transmitted from the motor gear 1 to the paper feed gear 4 via the reduction gear 3, and paper feeding becomes possible by operating the trigger mechanism. Power is not transmitted and the print head 100 does not reciprocate from side to side.

In the embodiments described above, when paper is inserted, the leading edge of the paper lifts up, or when paper is continuously fed, paper sag occurs due to paper being pressed at the paper exit section, and the paper is caught at the leading edge of the print head, resulting in a paper jam. By turning on an electric signal to the coil 53 and not operating the head when there is a high possibility that a paper jam will occur, paper jams can be prevented when paper is inserted or when paper is continuously fed.

[Embodiment 3] Yet another embodiment of the printer will be described based on the drawings. FIG. 5 is a side view of the printer of the present invention. FIG. 6(a) is a front view of the printer of the present invention, where power is transmitted by the switching mechanism. 70 is a motor pulley,
71 is a paper feed pulley fixed to the paper feed shaft 4a, 72 is a paper feed transmission belt engaged with each motor pulley 70 to transmit the power to the paper feed pulley 71, and 73 is a head feed relay having a main gear. 74 is a head feed transmission belt engaged with each pulley in order to transmit the power of the motor pulley to the head feed relay pulley 73; 77 is a head feed shaft fixed to the frame 80; 75 is a heavy double of the head feed relay pulley 73; A head feed gear 76, which has meshable gears, has a head feed pulley 82 fixed to it or is integrally molded therewith, and is movable up and down with a head feed shaft 77 as a guide; 9 is the frame 8.
A solenoid 78 is fixed at 0 and can attract and repel the movable core 9a by an electric signal.One side of the solenoid 78 is engaged with the head feed gear 75 and the other is the movable core 9a of the solenoid 9.
A transmission switching lever 79 is engaged with the fulcrum shaft 81 and is rotatable around the fulcrum shaft 81.
This is a head feed boob presser spring that works to engage 7.

Next, the operation of the present invention will be explained. FIG. 5 is a side view of the printer of the present invention. FIG. 6(a) is a front view showing a state in which the printer according to the present invention can print. Here, the solenoid 9 is in a state of repulsion due to the electric signal, and the head feed gear 75 is engaged with the head feed relay pulley 73 by the head feed pulley presser spring 79. At this time, the power of the motor generated by the electric signal is transmitted from the motor pulley 70 to the paper feed pulley 71 via the paper feed transmission belt 72. A paper feeding operation is performed by operating a trigger mechanism (not shown) on the paper feeding shaft 4a. At this time, the power of the motor is simultaneously transmitted to the head feed relay pulley 73.

Further, the power is transmitted to the head feed gear 75, the coaxial head feed pulley 82 rotates, and the head feed belt 76 operates, thereby causing the engaged print head 100 to reciprocate from side to side, making it possible to print.

FIG. 6(b) is a front view showing a state in which the printer according to the present invention can insert paper and continuously feed the paper. Here, the solenoid 9 is in a attracted state due to the electric signal. When the movable core 9a of the solenoid 9 is attracted by the head feed pulley presser spring 79, the transmission switching lever 78 engaged with the movable core 9a rotates about the fulcrum shaft 81.

At this time, the head feed gear 75 engaged with the other transmission switching lever 78 slides downward, and the engagement with the head feed relay pulley 73 is released. At this time, when the motor is driven by an electric signal, power is transmitted from the motor pulley 70 to the paper feed shaft 4a via the paper feed transmission belt 72, and paper feeding is possible by operating the trigger mechanism, but the head feed pulley 82 Since no power is transmitted to the print head 100, the print head 100 does not reciprocate from side to side.

In the above-described embodiments, the leading edge of the paper may float when the paper is inserted, or the paper may sag due to the paper being pressed at the paper exit section during continuous paper feeding, and the paper may be caught by the leading edge of the print head. By sucking the solenoid 9 and not operating the print head 100 when a paper jam is likely to occur, it is possible to prevent a paper jam when inserting paper or when paper is continuously fed.

〔Effect of the invention〕

As explained above, the printer of the present invention has a simple structure in which a switching mechanism is provided in the middle of the blade feeding means, so that the print head is not operated when paper is inserted or paper is continuously fed, thereby preventing paper jams. It definitely has a preventive effect.

Further, the present invention is effective in improving the durability of the head feeding mechanism and reducing noise generated by the reciprocation of the head, since the number of operations of the print head is reduced.

[Brief explanation of drawings]

1 and 2 are side views of a printer according to a first embodiment of the present invention. FIG. 3 is a side view of a printer according to a second embodiment of the present invention. FIGS. 4A to 4C are diagrams showing a switching mechanism section of a printer according to a second embodiment of the present invention. FIG. 5 is a side view of a printer according to a third embodiment of the present invention. 6(a) to 6(b) are front views of a printer according to a third embodiment of the present invention. FIG. 7 and FIG. 8 are diagrams showing the following. 1.. 2.. 3.. 4.. 4a. 5.. 5a. 6.. 6a. 7.. 8.. 9. 9a. 10. 50. 51. 52. 53. Conventional paper jam prevention mechanism・Motor gear ・Motor reduction gear ・Reduction gear ・Paper feed gear ・Paper feed shaft ・Head feed gear ・Head feed gear shaft ・Transmission gear ・Shaft・Spring・・Head feed cam・・Head feed trigger plate・・Head feed ratchet・・Coil 54 ・ 55 ・ 56 ・ 70 ・ 71 ・ 72 ・ 73 ・ 74 ・ 75 ・ 76 ・ 77 ・ 78 ・ 79 ・ 80 ・ 81・ 82 ・ 00 01 02 03 ・Trigger spring, head feed clutch spring, fulcrum, motor pulley, Fahrenheit feed pulley, paper feed transmission belt, head feed relay pulley, head feed transmission belt, head feed gear, head feed belt, head feed shaft・Transmission switching lever ・Head feed pulley holding spring ・Frame ・Fully shaft ・Head feed pulley ・・Print head ・・Paper ・・Elastic member ・・Space Fig. 4 (Q) 54 Fig. 4 (b) 52 Fig. 4 (C) Figure 6CQ) Figure 6(b)

Claims (1)

[Claims] A motor that generates power by an electrical signal, a paper feed transmission means that transmits the power of the motor to a paper feed shaft, a paper feed roller that functions to feed printed paper, and a paper feed gear shaft that transmits the power of the motor to the paper feed gear shaft. A clutch mechanism that serves to selectively transmit power to the paper feeding roller, a head feeding device that reciprocates the printing device, and a switching device that serves to selectively transmit the power from the motor to the head feeding device. A printer characterized by comprising: