JP3778257B2 - Roller urging device in recording apparatus and recording apparatus including the device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a roller urging device for urging a driven roller of a recording apparatus such as an ink jet printer to a driving roller, and a recording apparatus including the apparatus.
[0002]
[Prior art]
FIG. 6 and FIG. 7 show the state around the paper feed roller in the conventional ink jet printer. The paper feed roller includes a paper feed drive roller 101 and a paper feed driven roller 103, and the paper feed driven roller 103 is rotatably supported at the tip of the guide member 105.
[0003]
The guide member 105 is rotatably supported with respect to the shaft 107, and a torsion coil spring 109 is provided on the shaft 107. One end 111 of the torsion coil spring 109 is fixed to the upper surface of the guide member 105, and the other end 113 of the torsion coil spring 109 is engaged with a locking portion 117 extending from the back surface of the main frame 115 rising in the vertical direction as shown in FIG. It has stopped. Since both ends 111 and 113 of the torsion coil spring 109 are fixed to the guide member 105 and the main frame 115 in a state where an urging force to spread outward is stored, the guide member 105 is directed downward by the return force of the spring. As a result, the paper feed driven roller 103 is constantly pressed against the paper feed drive roller 101.
[0004]
[Problems to be solved by the invention]
In the above conventional structure, the other end 113 of the torsion coil spring 109 receives a component force in the direction indicated by f in the figure (hereinafter referred to as the f direction), so that the main frame 115 receives a force in the f direction. 6 and 7 are provided with a plurality of springs for urging the paper-driven driven roller 103 in the axial direction of the driven roller. A large force acts and the main frame 115 tends to bend in the f direction.
[0005]
However, since left and right side frames (not shown) connected to the sides of the main frame 115 support a carriage guide shaft (not shown) for guiding a carriage including a head, the main frame 115 is supported. When the taper is bent, the carriage guide shaft is moved up and down, and the distance between the head and the platen, that is, the paper gap is changed, so that high quality printing cannot be maintained.
[0006]
An object of the present invention is to provide a roller urging device in a recording apparatus and a recording apparatus including the apparatus that can prevent a main frame supporting the other end side of the torsion coil spring from being bent.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the roller urging device in the recording apparatus according to claim 1 of the present application supports the first roller rotatably and includes a plurality of guide members arranged in parallel in the axial direction of the second roller. An urging device for urging toward the two-roller side, wherein the urging device acts on the guide member to urge the guide member toward the second roller side, and a plurality of the guide members Is provided with a spring having a second end that is supported in a state in which a force acts in a direction substantially parallel to a direction in which the frame extends with respect to a support portion formed on a frame provided rotatably. Is.
[0008]
According to the present invention, even when the other end side of many springs is supported by the support portion of the frame, the frame hardly receives a force component in the direction perpendicular to the direction in which the frame extends. Is prevented.
[0009]
According to a second aspect of the present invention, in the roller urging device in the recording apparatus according to the first aspect, the spring is a torsion coil spring, and the other end of the torsion coil spring is substantially perpendicular to the frame. It is supported by the said support part in the state extended in this.
According to the present invention, the other end of the torsion coil spring mainly exerts a force component parallel to the extending direction of the frame on the frame, so that the frame has a force component perpendicular to the extending direction of the frame. I almost never get it.
[0010]
According to a third aspect of the present invention, in the roller urging device in the recording apparatus according to the first or second aspect, the first roller is a paper feed driven roller, and the second roller is a paper feed driving roller. It is characterized by being.
According to the present invention, the same effect as described above can be obtained without changing the urging state of the paper feed driven roller by the spring to the paper feed drive roller.
[0011]
According to a fourth aspect of the present invention, in the roller urging device in the recording apparatus according to any one of the first to third aspects, a carriage guide shaft is supported on the frame. It is.
According to the present invention, since the distance between the head of the carriage that scans along the carriage guide shaft and the platen, that is, the paper gap does not change due to the deflection of the frame, high-quality printing can be realized.
[0012]
The invention according to claim 5 is a recording apparatus comprising the roller urging device in the recording apparatus according to any one of claims 1 to 4. According to the present invention, since the frame is prevented from being bent, the position of the member supported by the frame including the carriage does not change, and high-quality printing can be realized.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view of an ink jet printer 1 having a roller urging device in a recording apparatus according to an embodiment of the present invention. Unit 5 and paper discharge unit 7.
[0014]
A paper feed tray 11 is formed in the paper feed unit 3, and a plurality of sheets P can be stacked on the paper feed tray 11. A paper feed roller 13 is provided immediately downstream of the paper feed tray 11. The paper feed roller 13 presses the paper P located at the uppermost part of the paper feed tray 11 between the opposing separation pads and feeds it forward.
[0015]
The fed paper P reaches a paper feed roller 19 composed of a lower paper feed drive roller 15 and an upper paper feed driven roller 17, and receives a precise paper feed operation in a printing process by a drive system (not shown). However, the paper is fed to the print head 21 located on the downstream side of the paper feed roller 19. The paper feed driven roller 17 is constantly urged to the paper feed drive roller 15 by a roller urging device described later, and the paper P is fed by the clamping force between the paper feed driven roller 17 and the paper feed drive roller 15. The driving force is applied to the paper P by being sandwiched.
[0016]
The print head 21 is supported by a carriage 23, and the carriage 23 can be reciprocated in a direction perpendicular to the paper feeding direction while being supported by a carriage guide shaft 24 extending in a direction penetrating the paper surface of FIG. . A platen 25 is provided at a position facing the print head 21, and the platen 25 serves to support the paper P from below when printing on the paper P by the print head 21.
[0017]
The distance between the print head 21 and the platen 25, that is, the paper gap, can be adjusted as appropriate according to the thickness of the paper P, so that the paper P can be smoothly printed on the platen 25 and high-quality printing can be performed. It can be done. The paper P printed by the print head 21 is sequentially discharged by a paper discharge roller 27 provided in the paper discharge unit 7.
[0018]
The paper discharge roller 27 is composed of a lower paper discharge drive roller 29 and an upper paper discharge driven roller 31, and serves as a mechanism in which the paper P is pulled out and discharged by the rotational drive of the paper discharge drive roller 29. Yes.
[0019]
As shown in FIG. 2, members around the printing unit 5 are supported by a frame member. The frame member includes a main frame 33 located on the rear side of the printing unit 5, side frames 35 located on both sides of the main frame 33, and a middle frame 37 located between both side frames 35. The entire frame member is configured by firmly connecting the frames to each other. Both ends of the carriage guide shaft 24 described above are supported by both side frames 35.
[0020]
In such a frame structure, for example, if the main frame 33 bends in the front-rear direction even a little, the side frame 35 that is firmly connected to the main frame 33 moves in the vertical direction, so both ends are supported by the side frame 35. The carriage guide shaft 24 also moves up and down, and accordingly, the distance between the print head 21 and the platen 25, that is, the paper gap fluctuates. In the present invention, in order to prevent such a situation, the biasing device that biases the paper feed driven roller 17 to the paper feed drive roller 15 employs a characteristic structure as described below.
[0021]
First, as shown in FIGS. 3 and 4, the main frame 33 is formed with a horizontal portion 39 extending substantially horizontally, and a guide member 41 is rotatably connected to the horizontal portion 39. Both ends of the two paper feed driven rollers 17 are rotatably supported on the tip end portion 43 of the guide member 41. A central portion 49 of the torsion coil spring 47 is held by the spring locking portion 45 formed in the horizontal portion 39, and one end 51 located on the front side of the torsion coil spring 47 is fixed to the upper surface of the distal end portion 43 of the guide member 41. ing.
[0022]
On the other hand, the other end 53 of the torsion coil spring 47 is formed with a locking action end 54 extending in the extending direction of the paper feed driven roller 17, and the other end 53 is formed in a notch 55 formed in the horizontal portion 39. The locking action end 54 is locked on the support portion 57 located at the base end of the horizontal portion 39 in a state of passing through. Since both ends of the torsion coil spring 47 are supported by the upper surface of the tip end portion 43 and the support portion 57 in a state of being bent upward from the free state of the spring, the one end 51 side of the spring is moved by the return force of the torsion coil spring 47. As a result, the paper feed driven roller 17 is pressed against the paper feed driving roller 15. A plurality of paper feed driven rollers 17 having the same structure as described above are provided along the paper feed drive roller 15.
[0023]
As shown in FIG. 4, the other end 53 of the torsion coil spring 47 extends rearward at a substantially horizontal angle. As a result, a downward force component F ₁ (in the direction in which the main frame 33 extends) The resultant force F of the force component) and the horizontal force component F ₂ (the force component in the direction in which the main frame 33 is bent) acts. Although the direction of the resultant force F is are longer shown in order to clearly show the horizontal force component F ₂ is substantially are parallel direction (i.e., vertical direction) (FIG. The direction of extension of the main frame 33, the actual is the horizontal force components F _2, small that the resultant force F is substantially perpendicular to). In this way, the force component F _{2 in the} horizontal direction out of the force that the other end 53 acts on the support portion 57 is extremely small, so that all of the torsion coil springs 47 provided along the paper feed driving roller 15 are all. the main frame 33 also align the horizontal force component F ₂ does not flex rearward.
[0024]
In the present invention, “the other end supported in a state in which a force acts in a direction substantially parallel to the extending direction of the frame with respect to the support portion formed on the frame” means the other end as described above. When 53 is supported by the support portion 57, the resultant force F of the force component in the direction parallel to the direction in which the frame extends and the force component in the direction in which the frame bends becomes substantially parallel to the direction in which the frame extends. It means the other end to which a force that does not bend acts.
[0025]
In the above embodiment, the support portion 57 is formed at the base end of the horizontal portion 39, and the other end 53 of the torsion coil spring 47 is locked to the upper surface thereof. For example, the other end of the torsion coil spring 47 is locked to a portion protruding from the main frame 33, or a hole is formed in the main frame 33, and the other end of the torsion coil spring 47 is formed in the hole. May be supported through. Of course, also in such a form, when the other end 53 is supported by the support portion 57, a force is applied in a direction substantially parallel to the extending direction of the frame.
[0026]
FIG. 5 shows an embodiment to which the present invention is applied in the form shown in FIG. 7 introduced as the prior art. In FIG. 5, reference numeral 59 denotes a main frame, and a spring support rod 61 extends in the horizontal direction behind the main frame 59. The one end 65 side of the torsion coil spring 63 is fixed to the guide member 41 as in the embodiment of FIGS. 1 and 4, and is the same in that the paper feed driven roller is biased toward the paper feed drive roller side. Omitted.
[0027]
The other end 67 of the torsion coil spring 63 is engaged with the lower side of the support portion 69 formed by bending backward from the main frame 59. Since the other end 67 of the torsion coil spring 63 extends substantially perpendicular to the direction in which the main frame 59 extends, the other end 67 of the spring 63 has an upward force component F ₁ ( The resultant force F of the force component in the direction in which the main frame 59 extends) and the horizontal force component F ₂ (the force component in the direction in which the main frame 59 bends) acts in a direction substantially parallel to the direction in which the main frame 59 extends. It has become. This embodiment is different from the embodiment shown in FIG. 1 in that the force component in the extending direction of the main frame 59 at the other end 67 of the torsion coil spring 63 is upward.
[0028]
In the embodiment shown in FIGS. 1 and 5, the torsion coil spring is used. However, when the paper feed driven roller is urged toward the paper feed drive roller side by another type of spring, the spring is also used. The end of the main frame supported by the main frame can be supported in a state in which a force acts in a direction substantially parallel to the direction in which the frame extends in the same manner as described above. Further, for example, even when the discharge driven roller 31 is urged against the discharge drive roller 29 using a spring with respect to a frame other than the main frame, when the frame is bent, the trouble is caused. Similarly to the above, the end of the spring supported on the frame side can be supported in a state where a force acts in a direction substantially parallel to the direction in which the frame extends.
[0029]
Further, when the frame on which the spring is supported extends in the horizontal direction or in the oblique direction, the end portion of the spring supported by the frame extends in the direction in which the frame extends (in order to prevent the frame from bending). It can be supported in a state in which a force acts in a direction substantially parallel to a horizontal direction or an oblique direction).
[0030]
【The invention's effect】
According to the present invention, even if the ends of many torsion coil springs are supported by the support portion of the main frame, the main frame receives almost no force component in the direction perpendicular to the main frame. Is prevented from bending. Accordingly, since the carriage guide shaft, which is supported at both ends by the side frame connected to the main frame, is prevented from moving up and down, the paper gap can be kept constant and high quality printing can be performed. Become.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an ink jet printer including a roller urging device in a recording apparatus of the present invention.
FIG. 2 is a top view of the periphery of a printing unit of the printer.
FIG. 3 is a perspective view showing a state around a guide member, a torsion coil spring, and a paper feed driven roller.
FIG. 4 is a side cross-sectional view showing the periphery of a guide member, a torsion coil spring, and a paper feed driven roller.
FIG. 5 is a sectional side view showing another embodiment of the roller urging device in the recording apparatus of the present invention.
FIG. 6 is a perspective view of a conventional paper feed driven roller urging mechanism as viewed from the front side.
FIG. 7 is a perspective view of a conventional paper feed driven roller urging mechanism as viewed from the back side.
[Explanation of symbols]
15 Paper feed driving roller 17 Paper feed driven roller 19 Paper feed roller 27 Paper discharge roller 29 Paper discharge drive roller 31 Paper discharge driven roller 33 Main frame 39 Horizontal portion 41 Guide member 43 Tip portion 45 Spring locking portion 47 Torsion coil spring 49 Center Part 51 One end of torsion coil spring 53 Other end of torsion coil spring 54 Locking end 55 Notch part 57 Support part 59 Main frame 61 Spring support rod 63 Torsion coil spring 65 One end of torsion coil spring 67 Other end 69 of torsion coil spring Support part F ₁ The vertical force component F _{2 at} the other end of the torsion coil spring F ₂ The resultant force of the horizontal force components F F ₁ and F _{2 at} the other end of the torsion coil spring

Claims (5)

An urging device for supporting a first roller rotatably and urging a plurality of guide members arranged side by side in the axial direction of the second roller toward the second roller,
The biasing device acts on the guide member to bias the guide member toward the second roller, and a support portion formed on a frame in which the plurality of guide members are rotatably provided. A roller urging device in a recording apparatus, comprising: a spring having a second end supported in a state in which a force acts in a direction substantially parallel to a direction in which the frame extends.   2. The roller according to claim 1, wherein the spring is a torsion coil spring, and the other end of the torsion coil spring is supported by the support portion in a state of extending substantially perpendicular to the frame. Energizing device.   3. A roller urging device according to claim 1, wherein the first roller is a paper feed driven roller, and the second roller is a paper feed drive roller.   4. The roller urging device in the recording apparatus according to claim 1, wherein a carriage guide shaft is supported on the frame.   A recording apparatus comprising the roller urging device in the recording apparatus according to claim 1.

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