JPH0717292B2 - Paper guide device for paper tractor - 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 guide device for movably disposing between a pair of paper tractors mounted in a printer to prevent the middle portion of recording paper from being bent. Is.

[0002]

2. Description of the Related Art Conventionally, a paper guide for preventing the intermediate portion of the recording paper from bending downward has been movably arranged between a pair of paper tractors. Most of the conventional paper guides for this purpose have a roller-like shape made of rubber or plastic. According to such a paper guide roller, a sufficient contact area with respect to the recording paper cannot be obtained, so that when the width of the recording paper becomes wide, the purpose thereof is not sufficiently achieved, and paper feeding failure may occur. For this reason, in general, a plurality of paper guide rollers are provided to deal with the above inconvenience.

Therefore, as a method for obtaining a sufficient bending prevention effect even for a wide recording paper, Japanese Utility Model Publication No. 59-22992 and Japanese Utility Model Publication No. 57-167856.
However, these papers have a drawback that the assembly of the paper guide device becomes complicated in combination with the incorporation of the paper tractor because the entire paper guide device is attached by penetrating the shaft of the paper tractor. Was there.

On the other hand, Japanese Patent Application Laid-Open No. 48-6634 discloses a device in which such a paper guide device can be mounted later in a snap fit type or a click fit type. However, there is a problem that it is difficult to assemble the paper guide device because the part to which the paper guide device is movably mounted is not the shaft of the paper tractor but other structural parts and is configured to be pushed straight from the top. Was there.

[0005]

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide a paper guide device for a vapor tractor which can be easily incorporated.

[0006]

In order to achieve the above object, according to the present invention, a cylindrical slider is fitted between a pair of paper tractors so as to be axially movable with respect to the shaft of the tractor. A paper guide device comprising a guide body that holds the slider from the outside and moves integrally with the slider, and a support frame that slidably supports the guide body in parallel with the axis of the tractor. The following configurations are used. The slider is fitted on the tractor shaft so that it can move when a force exceeding a certain frictional force is applied through a plurality of elastic pieces divided by a slit formed in the axial direction from one end. is doing. The guide body has a guide surface on its upper surface that is in sliding contact with the recording paper, and has side wall portions on both sides that have a notch portion that closely faces both end surfaces of the slider and that avoids the axis of the tractor. A plurality of elastic holding arms are hung so as to rotatably hold the outer peripheral surface of the slider from both sides. The support frame is formed with a guide piece slidably engaged with an engaging portion provided at one end of the guide body. The elastic holding arm is attached to the outer peripheral surface of the slider by turning the guide body toward the shaft of the tractor from the state where the guide body is inclined and the engaging portion is inserted into the guide piece and the guide piece is used as a fulcrum.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the preferred embodiments shown in the drawings. In FIG. 1, a pair of paper tractors 2 and 2 is arranged on a support frame 1. The internal structure of the paper tractors 2 and 2 will not be described in detail since it is not directly related to the gist of the present invention, but the belt 4 having the pin 4a engaging with the perforation 3a of the recording paper 3 is rotated by the rotation of the drive shaft 5. Then, the recording paper 3 is shown in FIG.
It sends it upwards. The paper tractors 2 and 2 are movable left and right according to the width of the recording paper 3. The drive shaft 5 has a rectangular cross section (a hexagon in this embodiment),
Although not shown in the drawing, both end portions thereof are rotatably supported by the support frame 1. A paper guide device 6 according to the present invention is provided between the paper tractors 2 and 2 in order to prevent the intermediate portion of the recording paper 3 from bending downward.

The paper guide device 6 is composed of a guide body 7 having a rectangular planar shape and a slider 8 for holding the guide body 7 at a desired position.

The slider 8 has a cylindrical shape with an outer peripheral surface having a circular cross section, and has a hexagonal shaft hole in which the drive shaft 5 is loosely fitted. A slit 8a is formed in the axial direction from one end of the slider 8, and a plurality of elastic pieces 8b are divided and formed by the slit 8a. The elastic piece 8b is elastically attached to the outer peripheral surface of the drive shaft 5 by its own elastic force. Therefore, the slider 8 can move in the axial direction only when a force greater than the frictional force of the elastic piece 8b on the drive shaft 5 is applied from the outside, and the slider 8 is maintained at that position by the frictional force.

The upper surface of the guide body 7 is a guide surface with which the recording paper 3 is in sliding contact, but a plurality of ribs 7a are projected at a slight height on the upper surface in order to reduce friction with respect to the recording paper 3. Has been formed. Side wall portions 7b, 7b are formed on both side portions of the guide body 7 so as to extend downward.
As shown in FIG. 3, b and 7b closely face both end surfaces of the slider 8. The drive shaft 5 is provided on both side wall portions 7b and 7b.
A cutout portion 7c is formed to allow the passage of (see FIG. 4). A plurality of (two in this embodiment) elastic holding arms 7d, 7d are formed on the back surface of the guide body 7 so as to hang down the outer peripheral surface of the slider 8 from both sides thereof. I have. Furthermore, a substantially U-shaped engaging portion 7e is formed at the front end portion (left side in FIG. 2 or FIG. 3) of the guide body 7, and the engaging portion 7e is formed.
e engages with the guide piece 1a of the support frame 1 slidably in the axial direction. The guide piece 1a is formed with an inclined guide surface 1b for smooth engagement of the engaging portion 7e.

Next, the assembly of the paper guide device 6 will be described. First, the slider 8 is inserted into the drive shaft 5 to support the drive shaft 5 by the support frame 1. After that, as shown in FIG. 4, the guide body 7 is slanted, the engaging portion 7e is applied to the guide piece 1b of the support frame 1, and the guide body 7 is rotated downward with the guide piece 1b as a fulcrum. . Then, the elastic holding arms 7d, 7d elastically spread outward and slide down along the outer peripheral surface of the slider, so that the elastic holding arms 7d, 7d of the guide body 7 smoothly fit on the outer peripheral surface of the slider 8. (Fig. 2).

The present invention is not limited to the above embodiments, but is specified only by the scope of claims for patent, and various modifications can be made without departing from the technical idea thereof.

[0013]

According to the paper guide device of the present invention constructed as described above, the guide body is tilted with respect to the support frame and the engaging portion is inserted into the guide piece, and the guide body is used as a fulcrum for the tractor. By rotating toward the shaft, the elastic holding arm of the guide body can be attached to the outer peripheral surface of the slider frictionally attached to the shaft of the tractor, so that the assembly is very easy and quick. It can be carried out.

[Brief description of drawings]

FIG. 1 is a plan view of a paper tractor to which a paper guide device according to the present invention is applied.

FIG. 2 is an enlarged cross-sectional view taken along the line AA of FIG.

FIG. 3 is a rear view showing the internal structure with the support frame omitted.

FIG. 4 is an explanatory view showing an assembling operation of the guide body.

[Explanation of symbols]

 1 Support Frame 1a Guide Piece 2 Paper Tractor 3 Recording Paper 5 Tractor Shaft 6 Paper Guide Device 7 Guide Body 7b Side Wall 7c Cutout 7d Elastic Holding Arm 7e Engagement 8 Slider 8a Slit 8b Elastic Piece

Claims (1)

[Claims] 1. A tubular slider fitted between a pair of paper tractors so as to be axially movable with respect to the shaft of the tractor, and a slider that is held from the outside and integrated with the slider. The slider comprises a moving guide body and a support frame slidably supporting the guide body parallel to the axis of the tractor. The slider is composed of a plurality of elastic members divided by a slit formed in the axial direction from one end. It is fitted to the shaft so that it can move when a force exceeding a certain frictional force is applied via a piece, and the guide body is provided with a guide surface on the upper surface that is in sliding contact with the recording paper. There is a side wall portion on both sides which closely faces both end surfaces of the slider and has a cutout portion for avoiding the shaft of the tractor, and the rear surface portion rotatably holds the outer peripheral surface of the slider from both sides. A number of elastic holding arms are formed so as to hang down, and a guide piece that slidably engages with an engaging portion provided at one end of the guide body is formed on the support frame. Is slanted and the locking body is inserted into the guide piece, and the guide body is rotated toward the shaft of the tractor with the guide piece serving as a fulcrum so that the elastic holding arm causes the outer peripheral surface of the slider to move. A paper guide device for a paper tractor, which is mounted on a paper.