JP3637953B2 - Paper feed roller support device for ink jet recording apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper feed roller support device and an ink jet recording for an ink jet recording apparatus, comprising: a bearing that supports both ends of the paper feed roller shaft so as to be slidable in the axial direction; It relates to the device.
[0002]
[Prior art]
A conventional example of a paper feed roller support device of this type of ink jet recording apparatus will be described with reference to FIGS. FIG. 6 is a schematic front view of the paper feed roller support device, FIG. 7 shows a portion of the positioning means, (A) and (B) correspond to each state where the E-ring is different from the positioning state, (A1) is a cross-sectional view of the E-ring portion viewed from the axial direction showing one state of the E-ring, (A2) is a front view of the main part in a positioning state corresponding to that state, and (B1) is a view of the E-ring Sectional drawing of the E-ring part seen from the axial direction which shows another state, (B2) is the principal part front view of the positioning state equivalent to the state.
[0003]
Both ends of the paper feed roller shaft 1 are pivotally supported by the side frames 2 and 3 via bearings 4 and 5 so as to be swingable in the axial direction. On one bearing 4 side of the paper feed roller shaft 1, an E-ring 6 is attached to the outer peripheral surface thereof, and a spring 7 that biases the paper feed roller shaft 1 toward the other bearing 3 is further contracted. ing. In the figure, reference numeral 8 denotes a spring seat, and the spring seat 8 is fixed to the outer peripheral surface of the paper feed roller shaft 1. The paper feed roller shaft 1 is urged toward the other bearing 3 by the urging force of the spring 7, and the E-ring 6 is pressed against the outer surface 9 of the one bearing 4, thereby positioning in the axial direction. Is done. In the figure, reference numeral 10 denotes a gear, which is integrally fixed to the end of the paper feed roller shaft 1 and rotated by the power of a drive motor (not shown), whereby the paper feed roller shaft 1 Is to rotate.
[0004]
[Problems to be solved by the invention]
In the conventional positioning means, when the side frame 2 is slightly inclined as shown in FIG. 7, the E-ring 6 can contact only a part with the outer surface 9 of the bearing 4. That is, as shown in FIG. 6, it becomes impossible to contact uniformly over the entire surface. When the paper feed roller shaft 1 rotates in this state, the main body portion 11 of the E ring 6 is pressed against the bearing 4 (FIG. 7A), and the notch portion 12 of the E ring 6 is brought into contact with the bearing 4. Two states occur, such as a pressed state (FIG. 7B). For this reason, the paper feed roller shaft 1 is misaligned in the axial direction in both states, which is one of the causes of print quality degradation. In particular, in an inkjet printer capable of high-quality printing equivalent to a photograph, a dot displacement of 10 to 20 μm can be visually observed as a reduction in image quality, and thus the displacement of the paper feed roller shaft 1 is not preferable.
[0005]
An object of the present invention is to provide a paper feed roller support device for an ink jet recording apparatus in which the paper feed roller shaft does not shift in the axial direction due to rotation, and an ink jet recording apparatus including the support device.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 of the present application includes a member that pivotally supports both ends of the paper feed roller shaft so as to be swingable in the longitudinal direction of the shaft, and positioning means for defining a position in the longitudinal direction of the shaft , Wherein the positioning means biases the paper feed roller shaft toward one end in the longitudinal direction of the shaft, and biases the biasing means with the biasing means. A positioning restriction member that is pressed against the paper feed roller shaft, and a projection that projects from the end face of the paper feed roller shaft at a substantially axial position. Positioning in the longitudinal direction of the shaft is performed by pressing against the member.
[0007]
According to the present invention, the paper feed roller shaft is positioned in the longitudinal direction of the paper feed roller shaft by pressing the projecting portion, which is the end surface of the paper feed roller shaft and projecting substantially at the axial center thereof, against the positioning regulating member. For this reason, even if the paper feed roller shaft rotates, the contact state between the protruding portion at the substantially axial position and the positioning regulating member does not change. Accordingly, there is no displacement in the longitudinal direction of the shaft due to the rotation of the paper feed roller shaft.
[0008]
According to a second aspect of the present invention, in the paper feed roller support device of the ink jet recording apparatus according to the first aspect, the protrusions substantially coincide with each other in the axis of the paper feed roller shaft. It is characterized in that it is provided integrally with the attached gear. This eliminates the need for special processing on the paper feed roller itself, and it is sufficient to replace only the gear portion due to wear of the protrusions, thereby reducing costs.
[0009]
According to a third aspect of the present invention, in the paper feed roller supporting device of the ink jet recording apparatus according to the first aspect, the protrusion is provided integrally with the shaft end of the paper feed roller shaft. It is characterized by this. Thus, the protrusion can be provided with high accuracy on the axis of the paper feed roller shaft, and positional deviation in the longitudinal direction of the shaft accompanying rotation can be prevented with high accuracy.
[0010]
According to a fourth aspect of the present invention, in the paper feed roller support device for an ink jet recording apparatus according to any one of the first to third aspects, the biasing means is provided at one end side of the paper feed roller shaft. The coil spring is contracted around the roller shaft end opposite to the positioning regulating member. According to the present invention, since there is only a bearing portion and a side frame on the side opposite to the positioning regulating member on the side where the coil spring is provided, the mounting operation of the spring is easy. .
[0011]
According to a fifth aspect of the present invention, in the paper feed roller support device for an ink jet recording apparatus according to any one of the first to third aspects, the urging means is provided at one end of the paper feed roller shaft. It is characterized by comprising a coil spring contracted around the roller shaft end on the same side as the positioning regulating member. As a result, the components of the positioning means can be concentrated in one place, so that a structural unit can be achieved, and the efficiency of the assembling work can be improved from this point.
[0012]
According to a sixth aspect of the present invention, there is provided an ink jet recording apparatus comprising the paper feed roller supporting device according to any of the first to fifth aspects. According to the present invention, since there is no positional deviation of the paper feed roller shaft, it is possible to maintain high print quality.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
<First Embodiment>
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a main part front view showing a paper feed roller support device of an ink jet recording apparatus according to a first embodiment of the present invention, and FIG. 2 shows a case where a side frame is tilted in the first embodiment. It is a principal part front view shown.
[0014]
In the present embodiment, as shown in FIG. 1, the positioning means includes a spring 7 made of a coil spring that is a biasing means that biases the paper feed roller shaft 1 toward one end in the longitudinal direction of the shaft. A spring seat 8 is provided on the inner side of the bearing 5 on the 3 side. Since the side frame 3 side provided with the spring 7 in this way is a simple structural part only with the bearing 5 and the side frame 3, the spring 7 can be easily mounted.
[0015]
The paper feed roller shaft 1 is urged toward the other side frame 2 by the urging force of the spring 7. The paper feed roller shaft 1 biased by the spring 7 is pressed against the positioning regulating member 20 and stopped. The positioning regulating member 20 is fixed to the side frame 2. A protrusion 21 protrudes from the end surface of the paper feed roller shaft 1 at a substantially axial position. In the present embodiment, the protrusion 21 is provided integrally with a gear 10 made of synthetic resin and attached to one end of the paper feed roller shaft 1 so that the respective axes are substantially coincident with each other. 1 itself is not specially processed to provide the protrusion 21. The gear 10 is fixed to the paper feed roller shaft 1 by a fixing tool 22. The paper feed roller shaft 1 is positioned in the longitudinal direction of the shaft by pressing the protrusion 21 against the positioning regulating member 20 by the biasing force of the spring 7. Other configurations are the same as those of the conventional example shown in FIG.
[0016]
Next, the operation of the first embodiment will be described. According to the present embodiment, without using an E-ring as in the prior art, by pressing the projecting portion 21 projecting substantially at the axial center position of the end surface of the paper feed roller shaft 1 against the positioning regulating member 20, Since the paper feed roller shaft 1 is positioned in the longitudinal direction of the shaft, even if the paper feed roller shaft 1 rotates, the contact state between the protruding portion 21 and the positioning regulating member 20 that are substantially in the axial position is maintained. does not change. Therefore, the rotation of the paper feed roller shaft 1 does not cause a positional shift in the longitudinal direction of the shaft.
[0017]
In particular, even when the side frame 2 is slightly tilted as shown in FIG. 7, the contact state between the protrusion 21 and the positioning regulating member 20 is almost the same as the point contact state. The rotation of 1 does not cause misalignment in the longitudinal direction of the shaft. Therefore, since it is hardly affected by the inclination of the side frame, it is easy to design and manufacture.
[0018]
<Second Embodiment>
Based on FIG. 3, another embodiment of the present invention will be described. In the present embodiment, the spring 7 as the urging means is opposite to that in FIG. 1 and is contracted around the roller shaft end on the positioning regulating member 20 side. The spring seat 8 is also used by the fixture 22. According to the present embodiment, since the components of the positioning means can be concentrated in one place, structural unitization can be achieved, and the efficiency of the assembly work can be improved from this point. FIG. 4 corresponds to FIG. 2, and the operation and effect are the same.
[0019]
<Third Embodiment>
Still another embodiment of the present invention will be described with reference to FIG. In this embodiment, the protrusion 31 is provided integrally with the shaft end of the paper feed roller shaft 1. The gear 10 is provided with an opening 32 for projecting the protrusion 31. Since other configurations are the same as those of the embodiment shown in FIG. 1, the same portions are denoted by the same reference numerals, and the description thereof is omitted. The spring 7 is provided on the side frame 3 side as in FIG. According to the present embodiment, since the protrusion 31 can be provided with high accuracy on the axis of the paper feed roller shaft 1, it is possible to prevent displacement in the longitudinal direction of the shaft accompanying rotation with high accuracy.
[0020]
In any of the above-described embodiments, the paper feed roller shaft 1 is mounted on the side frames 2 and 3 via the bearings 4 and 5, but this structure is not necessarily indispensable. Alternatively, the paper feed roller 1 may be directly fitted in the holes provided in the side frames 2 and 3.
[0021]
【The invention's effect】
According to the present invention, the protrusion of the paper feed roller shaft, which protrudes substantially at the axial center, is pressed against the positioning regulating member, so that the axial direction of the paper feed roller shaft is increased. Since the positioning is performed, even if the paper feed roller shaft rotates, the contact state between the protruding portion at the axial center position and the positioning regulating member does not change. Accordingly, there is no displacement in the longitudinal direction of the shaft due to the rotation of the paper feed roller shaft.
[Brief description of the drawings]
FIG. 1 is a main part front view showing a paper feed roller support device of an ink jet recording apparatus according to a first embodiment of the present invention.
FIG. 2 is a front view of a main part showing a case where a side frame is inclined in the first embodiment.
FIG. 3 is a front view of a principal part showing a paper feed roller support device of an ink jet recording apparatus according to a second embodiment of the present invention.
FIG. 4 is a front view of main parts showing a case where a side frame is inclined in the second embodiment.
FIG. 5 is a front view of an essential part showing a paper feed roller support device of an ink jet recording apparatus according to a third embodiment of the present invention.
FIG. 6 is a schematic front view of a conventional paper feed roller support device.
FIG. 7 shows a portion of positioning means of a conventional paper feed roller support device, (A1) is a sectional view of the E-ring portion viewed from the axial direction showing one state of the E-ring, and (A2) is in that state. It is a principal part front view of the corresponding positioning state, (B1) is sectional drawing of the E ring part seen from the axial direction which shows the other state of an E ring, (B2) is the principal part of the positioning state equivalent to the state It is a front view.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Paper feed roller axis | shaft 2 Side frame 3 Side frame 4 Bearing 5 Bearing 7 Spring 10 Gear 20 Positioning restriction member 21 Protrusion 31 Projection 32 Opening

Claims (6)

A paper feed roller support device for an ink jet recording apparatus, comprising: a member that pivotally supports both ends of a paper feed roller shaft so as to be slidable in the longitudinal direction of the shaft; and positioning means for defining a position in the longitudinal direction of the shaft,
The positioning means includes a biasing means that biases the paper feed roller shaft toward one end in the longitudinal direction of the shaft, a positioning regulating member that is pressed against the paper feed roller shaft biased by the biasing means, The paper feed roller shaft end face is provided with a protrusion protruding substantially at the axial center position, and the protrusion is pressed against the positioning regulating member to perform positioning in the axial direction of the shaft. A paper feed roller support device for an inkjet recording apparatus. 2. The paper feed roller of an ink jet recording apparatus according to claim 1, wherein the protrusion is provided integrally with a gear attached to one end of the paper feed roller shaft so that the respective axes are substantially coincident with each other. Support device. 2. The paper feed roller support device for an ink jet recording apparatus according to claim 1, wherein the protrusion is provided integrally with a shaft end of the paper feed roller shaft. 4. The biasing means according to claim 1, wherein the biasing means is a coil spring that is provided at one end side of the paper feed roller shaft and is contracted around a roller shaft end that is opposite to the positioning regulating member. A paper feed roller support device for an ink jet recording apparatus. 4. The biasing means according to claim 1, wherein the biasing means is a coil spring that is provided at one end side of the paper feed roller shaft and is contracted around a roller shaft end on the same side as the positioning regulating member. A paper feed roller support device for an ink jet recording apparatus. An ink jet recording apparatus comprising the paper feed roller support device according to claim 1.

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