JP2560611Y2 - Printer paper feeder - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder for a printer in which a paper feed mechanism, a print head moving mechanism, and the like are driven by a common drive motor.

[0002]

2. Description of the Related Art At present, printers occupy an important position as one of computer peripheral devices and OA devices.

[0003] The paper feeding of the printer may be performed by a motor or manually.
During normal printing, that is, after the print head has printed one line, the motor is used to feed the paper so that the print head is positioned at the position of the next print line. In addition, when a sheet is set in a printer or when a print start position is adjusted, it is common to manually rotate a sheet feed roller to feed the sheet.

Conventionally, a motor for driving a paper feed mechanism is provided independently of a motor for driving other mechanisms, and usually a stepping motor or a servo motor has been used. This is because it is possible to easily change the paper feed amount according to various printing operations. In other words, during normal printing, the paper is fed each time the print head prints one line, or quickly on blank lines where printing is not performed, thereby shortening the overall operation time of the printer. I have.

[0005]

[Problems to be Solved by the Invention] As the performance required of the printer, there is a demand for miniaturization and weight reduction. Especially,
Demands for miniaturization and weight reduction of computers, their peripheral devices, OA devices, and the like are increasing, and with the spread of portable computers and word processors, the demands for miniaturization and weight reduction are expected to increase in the future.

In order to respond to the trend of miniaturization and weight reduction,
In the above-described method of installing a drive motor dedicated to paper feed, the weight and installation location of the drive motor impede reduction in size and weight.

Therefore, a drive motor for the paper feed mechanism, a mechanism for moving the print head in a direction perpendicular to the paper feed direction,
By sharing a drive motor such as a ribbon feed mechanism, it is conceivable to reduce the number of drive motors, and reduce the weight and installation location. As a result, the size and weight of the printer can be reduced, and the cost can be reduced.

However, since a common drive motor is used for each mechanism as described above, the operation of rotating the drive motor and feeding a predetermined amount of paper only when paper feeding is necessary cannot be performed. For example, the paper is not fed while the print head is printing, and it is not necessary to rotate the motor when viewed from this surface. On the other hand, since the print head performs printing while moving, it is necessary to rotate the motor. When the drive motors of the mechanisms having different demands are shared, it is necessary to take some measures. Generally, a paper feed roller shaft is driven via a transmission mechanism, and this transmission mechanism is provided with, for example, a clutch mechanism. With this configuration, the clutch is connected only when necessary, and the paper feed roller shaft rotates, so that the paper can be fed.

On the other hand, the paper feed mechanism is also required to rotate the paper feed roller manually and set the paper as described above. However, when a cam mechanism is provided in the transmission mechanism as described above, when the paper feed roller shaft is directly rotated, the rotation is hindered by the cam mechanism.
Therefore, there is a problem that the paper feed roller cannot be manually rotated, and it is very difficult to set paper in the printer.

The problem to be solved by the present invention is that in a printer apparatus having a common drive motor for each movable mechanism having the above-mentioned problem, how to set a sheet and adjust a print start position can be easily performed. The point is to supply a printer paper feeder.

[0011]

According to the present invention, the paper feed roller shaft can be rotated manually, and the driving force from the drive motor is temporarily transmitted to the paper feed roller shaft. A driving force transmission mechanism for

The transmission mechanism is rotatably supported by the paper feed roller shaft so as to be axially movable and rotatable, has a clutch surface on a side surface thereof, and receives a driving force from the motor, and A clutch wheel coaxially fixed to the paper feed roller shaft and a side surface of which faces the clutch surface of the rotating gear; a pin fixed to a frame; and the rotating gear integrally rotates and engages with the pin. A cam having an engagement surface and a separation surface for controlling the movement of the rotating gear in the axial direction.

[0013]

In a paper feeder of a printer capable of manually rotating a paper feed roller shaft, a driving force transmitting mechanism temporarily transmits a driving force from a drive motor to the paper feed roller shaft.

In the driving force transmission mechanism, the clutch surface of the rotating gear is connected to the clutch wheel only when the pin is engaged with the engagement surface of the cam, and the driving force is transmitted to the paper feed roller shaft. . When the pin is engaged with the separation surface of the cam, the rotating gear is separated from the clutch wheel, and the paper feed roller shaft is separated from the motor.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a driving force transmission mechanism of the paper feeding device according to the present invention, wherein FIG. 1A is a front view thereof, and FIG. 1B is a side view thereof.

The manual knob 1 is coaxially fixed to a paper feed roller shaft 2. A paper feed roller (not shown) is coaxially fixed to the paper feed roller shaft 2. Therefore, the paper feed roller rotates integrally with the paper feed roller shaft 2 and the manual knob 1, and the paper feed is performed by rotating the manual knob 1. Further, a clutch wheel 3 is coaxially fixed to the paper feed roller shaft 2.

The rotating gear 4 is coaxially arranged on the paper feed roller shaft 2, but unlike the manual knob 1 and the clutch wheel 3, the rotating gear 4 is rotatable and movable in the axial direction. It is pivoted. The rotating gear 4 and the clutch wheel 3 are arranged adjacent to each other. A spring 6 is interposed between the rotating gear 4 and the frame 5, and the spring 6 urges the rotating gear 4 toward the clutch wheel 3.

The surfaces of the rotating gear 4 and the clutch wheel 3 which face each other are formed with clutch surfaces 4a and 3a having saw-like teeth provided on the circumference. Also, the rotating gear 4
Has a groove cam 7 on its outer peripheral portion, and the groove cam 7 has a separation surface 7a and an engagement surface 7b. A pin 10 that engages with the groove cam 7 is fixed to the frame 5, and the pin 10 and the groove cam 7 control whether the rotating gear 4 is engaged with or disengaged from the clutch wheel 3. . Further, a gear portion 4b is also provided on the outer peripheral portion of the rotating gear 4. Gear part 4 of this rotating gear
b meshes with a gear portion 8 b provided at one end of the swing gear 8.

The swing gear 8 is rotatably supported by a support shaft 11. At the other end of the swing gear 8, a pusher 8a is provided at the other end. The pusher 8a engages with a feed cam 9 rotated by a drive motor (not shown), and a cam ridge 9a provided on the feed cam 9 is provided. It is pushed by. By this pushing, the swing gear 8 swings, and the rotating gear 4 rotates.

The above is the configuration of one embodiment according to the present invention. Hereinafter, a case where the paper feed roller shaft is rotated by the motor via the transmission mechanism and a case where the paper feed roller shaft is rotated by the manual knob will be sequentially described.

(Case where Paper Feed Roller Shaft is Rotated by Motor) A description will be given with reference to FIGS. 1, 2 and 3. FIG. 2, FIG.
FIG. 4 is an explanatory diagram of the operation of the driving force transmission mechanism. FIG.
3A is a development view of the rotating gear 4 and an outer peripheral portion of the clutch wheel 3. FIG.

In FIG. 1, the driving force of a motor (not shown) causes the feed cam 9 to rotate. The cam ridge 9a provided on the feed cam 9 pushes the pressing member 8a of the swing gear 8. In response to this pushing, the swing gear 8 swings, and the swing of the swing gear 8 is transmitted by the gear portion 8b of the swing gear and the gear portion 4b of the swing gear, and the swing gear 4 rotates. Move.

In FIG. 2, when the swing gear 8 starts swinging in the direction of arrow K, the rotating gear 4 starts rotating in the direction of arrow L. In FIG. 2A, the rotation of the rotating gear 4 is a movement in a direction indicated by an arrow M. Accordingly, the groove cam 7 on the outer periphery of the rotating gear also starts moving in the direction of arrow M, and the pin 10 engaged with the separation surface 7a of the groove cam is separated from the separation surface 7a of the groove cam. On the other hand, the rotating gear 4 is urged in the direction of the arrow N by the spring 6 as described above.
Then, when the pin 10 separates from the separation surface 7a of the groove cam, the rotating gear 4 moves in the direction of the arrow N in FIG. The clutch surface 4a on the side of the rotating gear and the clutch surface 3a on the side of the clutch wheel are joined, and the rotation of the rotating gear 4 is transmitted to the clutch wheel 3. FIG. 3 shows this state. Groove cam 7 and pin 1
The relationship of 0 moves from the position of the dashed line to the position of the solid line,
Rotating gear 4 and clutch surface 4 of each clutch wheel 3
a and 3a are joined. The driving force of the driving motor transmitted to the clutch wheel 3 rotates the paper feed roller shaft 2 to which the clutch wheel 3 is coaxially fixed. Then, paper feeding is performed.

As described above, the swing gear 8 swings in the direction of arrow K,
The case where the rotating gear 4 rotates in the direction of the arrow L has been described. After this operation is completed, an operation of returning to the initial state is performed. In this case, the swing direction of the swing gear 8 and the rotation direction of the rotating gear 4 are opposite to the directions of the arrows K and L. At this time, the clutch constituted by the rotating gear 4 and the clutch surface on each side surface of the clutch wheel 3 forms a one-way clutch, and does not transmit the reverse rotation to the paper feed roller shaft 2.

As described above, when paper is fed by the drive motor, the driving force is transmitted only in one direction, that is, in the direction of arrow L, and the paper is fed.

As described above, the driving force is transmitted to the paper feed roller shaft 2 only at a desired time during rotation of the motor, that is, when the feed cam 9 swings the swing gear, and the paper feed is intermittently performed. Is performed. As a result, the paper feed mechanism can be driven by a motor common to a drive motor such as a print head.

(In the case where paper is fed by a manual knob) As described above, the manual knob 1 and the paper feed roller are coaxially fixed to the paper feed roller shaft 2, so that if the manual knob 1 is rotated, the paper feed is performed. Done. At this time, if the manual knob 1 is rotated in both the forward and reverse directions, the paper feed is performed in the forward and reverse directions accordingly. This makes it possible to set a sheet, adjust a printing start position, and the like.

As described above, when paper is fed by the manual knob 1, the drive motor is not rotating. Therefore, the rotating gear 4 and the clutch wheel 3 are separated from each other, and the paper can be fed without being hindered by the driving force transmission mechanism.

As described above, in this embodiment, the paper is fed by the manual knob 1 when the paper is set in the printer or the printing start position is adjusted, and the motor is transmitted via the driving force transmission mechanism during normal printing. Paper feed. When the paper is fed by the manual knob 1, the paper can be fed without being hindered by the driving force transmission mechanism as described above.

The present embodiment is characterized in that the groove cam 7 and the gear portion 4b are provided on the same circumference of the rotating gear 4. That is, compared to the case where the groove cam 7 and the gear portion 4b are separately arranged in the axial direction, the dimension in the axial direction can be shortened, and the outer shape of the printer can be reduced.

Further, the present invention is characterized in that the swing gear 8 is used for transmitting the driving force from the motor to the paper feed roller shaft 2. Thereby, the number of parts can be reduced as compared with the case where the driving force is transmitted by the gear train. When the driving force is transmitted by rotational motion, it is necessary to use a full-circumferential gear. However, since the power is transmitted by oscillating motion, a partial gear structure is adopted, and the groove cam 7 and the gear 4b
This is also helpful in the configuration provided with.

In this embodiment, the manual knob 1 is coaxially fixed to the paper feed roller shaft 2, but the paper feed roller shaft 2 may be rotated via a gear train. In this case, the paper feed roller shaft 2
There is no need to make the rotation axis of the manual knob 1 coincide with the rotation axis of the manual knob 1, and the degree of freedom in design is increased.

[0034]

As described above, it is possible to realize a paper feeder of a printer which shares a drive motor for a print head moving mechanism and a paper feed mechanism and can perform both manual paper feed and motor paper feed. As a result, it is possible to provide a printer that is lightweight, compact, easy to operate, and inexpensive.

[Brief description of the drawings]

FIG. 1 is an overall view of a driving force transmission mechanism of a paper feeding device according to the present invention.

FIG. 2 is an explanatory diagram of an operation of a driving force transmission mechanism.

FIG. 3 is an explanatory diagram of an operation of a driving force transmission mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Manual knob 2 Paper feed roller shaft 3 Clutch wheel 4 Rotating gear 7 Groove cam 10 Pin

Claims (1)

(57) [Scope of request for utility model registration] 1. A paper feeder for a printer having a driving force transmission mechanism capable of manually rotating a paper feed roller shaft and temporarily transmitting a driving force from a motor to the paper feed roller shaft. A rotating gear that is axially movable and rotatably supported by the paper feed roller shaft and has a clutch surface on a side surface thereof, and a driving force transmitted from the motor; The clutch wheel is coaxially fixed to the paper feed roller shaft, the side surface of which faces the clutch surface of the rotating gear, a pin fixed to a frame, and rotates integrally with the rotating gear, and engages with the pin. A cam having a mating engagement surface and a separation surface, and controlling the axial movement of the rotation gear; and a clutch surface of the rotation gear only when the pin is engaged with the engagement surface of the cam. But clutch wheel And the driving force is transmitted to the paper feed roller shaft, and when the pin is engaged with the separation surface of the cam, the rotating gear is separated from the clutch wheel, and the paper feed roller shaft is separated from the motor. Characteristic printer paper feeder.