JPH0692177B2 - Paper feeder - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device provided with a tractor.

2. Description of the Related Art As shown in FIG. 4, in a printer including a tractor 50, the tractor 50 is generally provided near a platen 51.

Therefore, it is necessary to open the cover of the printer and attach the leading end of the paper 52 to the tractor 50 at a portion where the parts near the platen 51 are crowded. Therefore, the paper 52 tractor
The set to 50 is troublesome. Further, even when a jam occurs between the tractor 50 and the platen 51, this portion is congested, and thus it is difficult to remove the jam.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a sheet feeding device capable of easily mounting a sheet on a tractor and handling a jam.

Means for Solving the Problems A pair of left and right side plates for holding the platen is provided with a guide portion having a long hole in a direction away from the vicinity of the platen,
A transmission mechanism that is connected to a motor and drives the platen is attached to the side plate with its position fixed, and both ends of a drive shaft having one end fixed with a tractor gear that selectively meshes with the output gear of the transmission mechanism are connected to the platen. For feeding the paper to a holder slidably fitted to the guide portion so as to move between a first position close to the platen and a second position separated from the platen, and slidably held by the drive shaft. A tractor having a plurality of pins and mounted with a rotating body connected to the drive shaft is urged in a direction away from the platen, and the drive shaft is provided with an output gear of the transmission mechanism and the tractor gear. A pair of left and right locking mechanisms are provided to release the holding state at the first position by holding and operating it at the first position where they engage with each other.

When printing using a tractor, the output shaft of the transmission mechanism and the tractor gear can be engaged by holding the drive shaft that holds the tractor in the first position by the lock mechanism, which allows the drive force to be set at the same time as setting the position. Can be applied to the tractor, and when the paper is set or a jam occurs, the drive shaft is released from the platen by releasing the holding of the drive shaft by the locking mechanism, so it moves to the second position away from the platen. Moreover, the meshing between the output gear and the tractor gear can be separated, and the space around the platen can be widened, so that the work can be easily performed.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 to 3. Although only one side is shown, the platen 2 is rotatably held by the pair of left and right side plates 1. A transmission mechanism 3 located near the right end of the platen 2 is provided on the right side plate 1. The transmission mechanism 3 includes a transmission gear 5 meshed with a platen gear 4 fixed to the right end of the platen 2 and an output gear 6 meshed with the transmission gear 5. The transmission gear 5 is connected to a motor (not shown).

Next, a tractor 7 is provided. This tractor 7
Includes a pair of left and right holders 10 slidably fitted on the drive shaft 8 and the guide shaft 9, and a drive wheel 11 driven by the drive shaft 8 and a plurality of pins 12 on the outer periphery of the holder 10 are slidably fitted to the holders 10. A belt 13 that is a rotating body that is driven by the drive wheel 11 and a rotatable paper retainer 14 are mounted. A roller 15 is rotatably fitted to both ends of the drive shaft 8 and the guide shaft 9, and a tractor gear 16 is fixedly fitted to the right end of the drive shaft 8.

Thus, the left and right side plates 1 are formed with elongated holes 17 which are guide portions for rolling the rollers 15 and are inclined rearward and upward from the vicinity of the platen 2. At both ends of the guide shaft 9 projecting from the elongated hole 17, ends of springs 18 for biasing the tractor 7 rearward are fixed. A locking mechanism 19 is urged upward by a spring 20 on the left and right side plates 1 so as to be slidable within a certain range. The locking mechanism 19 includes a recess 21 for holding the roller 15 fitted to the drive shaft 8 and an elongated hole 17.
An inclined surface 23 that intersects the lower edge 22 at a pure angle is formed.

In such a configuration, the state shown in FIG. 2 is a state in which the tractor gear 16 meshes with the output gear 6. Therefore, when the motor is driven, the platen 2 rotates clockwise, the belt 13 rotates counterclockwise, and the paper 24 is fed.

When the lock mechanism 19 is pushed down from the state shown in FIG.
Force causes the drive shaft 8 and the guide shaft 9 to move rearward and upward, and the tractor 7 is largely separated from the platen 2. Therefore, at the position of this tractor 7, the leading edge of the paper 24 is
It is possible to easily perform the work of sandwiching between 13 and the paper retainer 14 in a wide working space. Then, the drive shaft 8 and the guide shaft 9 are moved to the platen 2 side along the long hole 17, and the locking mechanism is moved.
19 is temporarily retracted downward due to the contact between the inclined surface 23 and the roller 15, and then is lifted by the spring 20 to have the concave portion 21 and the drive shaft 8
Holds the roller 15. In this state, the motor is driven to rotate the platen 2 and the belt 13 of the tractor 7 to complete the setting of the paper 24 on the platen 2.

Further, even when a jam occurs between the tractor 7 and the platen 2, the jammed paper 24 can be easily taken out by moving the tractor 7 rearward.

EFFECTS OF THE INVENTION As described above, according to the present invention, the pair of left and right side plates that hold the platen are formed with the guide portions by the long holes in the direction away from the vicinity of the platen, and are connected to the motor to drive the platen The mechanism is attached to the side plate with its position fixed, and both ends of the drive shaft, which has one end fixed with a tractor gear that selectively meshes with the output gear of the transmission mechanism, are separated from the first position close to the platen and the platen. The drive shaft is provided with a plurality of pins for paper feed in a holder slidably fitted to the guide portion so as to move between the drive shaft and the second position. A tractor having a rotating body connected thereto is biased in a direction away from the platen, and the drive shaft is held at a first position where the output gear of the transmission mechanism and the tractor gear mesh with each other. Since a pair of left and right lock mechanisms that move by operating between the drive shaft holding position and the release position that frees the drive shaft are provided, the drive shaft that holds the tractor during printing using the tractor is provided. By holding the lock mechanism at the first position, the output gear of the transmission mechanism and the tractor gear can be engaged with each other.
The drive force can be applied to the tractor at the same time as the position setting, and when the paper is set or a paper jam occurs, the drive shaft is released from the platen by releasing the holding of the drive shaft by the locking mechanism. The second gear is moved to the second position, and the meshing between the output gear and the tractor gear is separated, so that the space around the platen can be largely opened, and the work can be easily performed.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 3 show an embodiment of the present invention. FIG. 1 is an exploded perspective view, FIG. 2 is a side view showing a paper loading state, and FIG. FIG. 4 is a side view showing a state in which the paper is set on the tractor, and FIG. 4 is a side view showing a conventional example. 2 ... Platen, 3 ... Transmission mechanism, 6 ... Output gear, 7
...... Tractor, 8 …… Drive shaft, 9 …… Guide shaft, 10 …… Holder, 12 …… Pin, 13 …… Belt (rotating body), 16 …… Tractor gear, 17 …… Groove (guide part), 19 ...... Lock mechanism

Claims (1)

[Claims] 1. A pair of left and right side plates for holding a platen are provided with guide portions each having a long hole extending in a direction away from the vicinity of the platen, and a transmission mechanism connected to a motor for driving the platen is provided in the side plate. Fix the position and install,
The tractor gear that selectively meshes with the output gear of the transmission mechanism is fixed at one end so that both ends of the drive shaft are moved between a first position close to the platen and a second position separated from the platen. Slidingly fitted to the guide part,
A tractor having a plurality of pins for feeding a sheet mounted on a holder slidably held by the drive shaft and having a rotating body connected to the drive shaft is urged in a direction away from the platen. A pair of left and right locking mechanisms are provided to hold the drive shaft at a first position where the output gear of the transmission mechanism meshes with the tractor gear and to operate the drive shaft to release the holding state at the first position. Paper feeding device characterized by.