The entire disclosure of Japanese Patent Application No: 2010-146230, filed Jun. 28, 2010 is expressly incorporated by reference herein.
1. Technical Field
The present invention relates to recording apparatuses.
2. Related Art
Ink jet printers (hereinafter simply referred to as “printers”) that eject ink from a recording unit such as a recording head onto a paper sheet so as to record a certain image (including characters and graphics) are an example of a type of recording apparatus that ejects liquid such as ink onto a recording medium such as a paper sheet so as to perform a recording operation.
Such printers are provided with a feeding cassette containing a plurality of stacked paper sheets therein (hereinafter simply referred to as a “cassette”) and are configured to record images on the paper sheets while feeding the uppermost paper sheets one by one toward the recording unit. Accordingly, the printers include a mounting unit in which the cassette containing a plurality of stacked paper sheets therein is detachably mounted by inserting the cassette in a direction perpendicular to a stack direction of the paper sheets and a paper feeding roller that separates the paper sheets one by one and feeds out the separated paper sheets from the cassette in a mounted state in the mounting unit toward the recording unit in a sequential manner.
The printer further includes a separation slope that is disposed at the internal end face of the mounting unit in which the cassette is mounted, that is, at a position opposite the front end of the cassette in a mounted state in the mounting unit in the insertion direction. The separation slope is formed to guide the paper sheets toward the recording unit when the paper feeding roller separates the paper sheets one by one and feeds out the separated paper sheets from the cassette.
Since the cassette is mounted in the mounting unit by a user, when the cassette is inserted into the mounting unit at a rapid speed, some of the paper sheets stacked in the cassette may be urged in the insertion direction by the inertia force and may be disposed on the rising separation slope. As a consequence, the separation slope fails to separate the paper sheets one by one, thereby causing a double feeding state in which two or more paper sheets are fed together. This may cause a problem such as a paper jam.
JP-A-2000-335769 discloses a mechanism for preventing the above-mentioned problem, in which a shutter member that moves downward from a retreat position in an upper region to a control position in a lower region is provided so that the shutter member controls the movement of the end of the paper sheets downstream in the feeding direction (hereinafter referred to as a “leading edge of the paper sheets”) in the insertion direction of the cassette. The lower end of the shutter member is configured to rotate upstream in the feeding direction when the shutter member moves up from the control position in the lower region where the shutter member abuts the leading edge of the respective paper sheets to the retreat position in the upper region. With this configuration, the shutter member permits the leading edge of the respective paper sheets abutting the shutter member and to be aligned with the slope surface such that the leading edge of the paper sheet in the higher position in the stack comes to a position more downstream in the feeding direction.
However, with the configuration disclosed in JP-A-2000-335769, a space for providing a rotation mechanism and a slide mechanism for sliding the shutter member into the retreat position while rotating the shutter member is needed. In addition, a space for housing the shutter member, the rotation mechanism and the slide mechanism is also needed. Those spaces cause a problem in that the printer becomes large.
In order to solve the above problem, for example, a configuration using a control member that has a control surface to control the movement of the paper sheet in the forward direction of the insertion direction of the cassette and that rotates to turn over in the insertion direction has been proposed. That is, in this case, the movement of the paper sheet is controlled by the control surface and the momentum of the paper sheet is reduced, and then, the control of the movement of the paper sheet is released when the control surface rotates so as to retreat from the separation slope with a predetermined time delay.
With this configuration, the paper sheets are separated one by one and guided to the recording unit without being disposed on the separation slope. As a result, only a space for a rotation movement mechanism of the control member is required without having to provide a wide space for housing a shutter member, a rotation mechanism and slide mechanism into the retreat position, therefore it is possible to prevent a printer from becoming large.
During such a rotation movement of the control member, a damper member is used to cause a predetermined time delay after controlling the movement of the paper sheets. That is, since a movement member of the damper member moves with a resistance, a time delay is generated between the time when the movement of the paper sheets is controlled and the time when the control is released by the rotation movement of the control member.
In such a damper member, since the control member moves cooperatively with the moving member, the control member has a cam that comes into sliding contact with a cam face of the moving member. However, when the paper sheets strongly collide against the control surface of the control member, the moving member fails to fully support the control member and is forced to move immediately without generating a predetermined time delay for the rotation operation of the control member. That is, the control member cannot resist the impact of the paper sheets and is forced to rotate to the release position and releases the control of the movement of the paper sheets before fully controlling the movement of the paper sheets. This results in a problem in that the control member fails to fully control the movement of the paper sheets.
An advantage of an aspect of the invention is that a damper device, a transportation device and a recording apparatus capable of fully controlling the movement of the object by using a control member is provided.
According to an aspect of the invention, a recording apparatus includes a control member that is configured to be rotatable about a shaft and controls the movement of an object contained in a container by coming into contact with the object when the object moves in an insertion direction from the container and a damper member that rotates the control member from a control position where the movement of the object is controlled to a release position where the control of the movement of the object is released with a time delay, the damper member including a moving member that has a cam face with which a cam of the control member comes into sliding contact and moves in the insertion direction from a first position to a second position with a resistance when the container is inserted into the mounting unit, wherein the cam face includes a first cam face on which the cam slides when the moving member moves from the first position to the second position and a press cam face that is arranged so as to oppose the first cam face and against which the cam presses when the object comes into contact with the control member, and the press cam face has an inclination relative to a reference straight line which is perpendicular to a plane parallel to the insertion direction of the container which is greater than that relative to a straight line which extends from the contact point between the press cam face and the cam to the shaft.
Accordingly, the component of the force that acts in the moving direction of the moving member of the force which is exerted by the cam on the press cam face due to the impact of the control member coming into contact with the object is reduced. Therefore, the movement of the moving member in the insertion direction by the force exerted by the cam on the press cam face due to the impact of the object coming into contact with the control member is restrained, and accordingly, the rotation of the control member to the release position due to the impact of the object coming into contact with the control member is restrained. As a result, it is possible for the control member to fully control the movement of the object.
According to the recording apparatus of the invention, an angle between the press cam face and the reference straight line is 90 degrees or less. Accordingly, when the moving member moves from the first position to the second position, the cam pressing against the press cam face can smoothly move to the first cam face so as to come into contact with the first cam face.
According to the recording apparatus of the invention, the press cam face is flat. Accordingly, variations in shape of the press cam face can be reduced. According to the recording apparatus of the invention, the moving member includes a second cam face on which the cam is guided to the press cam face when the moving member moves from the second position to the first position.
Accordingly, the cam slides on the second cam face to the press cam face when the moving member moves from the second position to the first position, therefore the control member can smoothly move from the release position to the control position.
According to the recording apparatus of the invention, an angle between the second cam face and the reference straight line is smaller than the angle between the press cam face and the reference straight line. Accordingly, the amount of rotation of the control member from the release position to the control position can be obtained with a relatively small amount of movement of the movement member.
According to the recording apparatus of the invention, the press cam face and the second cam face are continuous. Accordingly, the size of the moving member can be reduced and the number of components constituting the moving member can by reduced compared with the case where the press cam face and the second cam face are formed spaced from each other.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
With reference to the drawings, a damper member of the present invention will be described below according to an embodiment of an ink jet printer as a recording apparatus including a transportation device having such a damper member. The terms “forward-backward direction”, “left-right direction” and “up-down direction” as used herein refer to the forward-backward direction, left-right direction and up-down direction indicated in
As shown in
First, the mounting unit 13 is disposed in a lower area in the frame 12 and communicates with the outside of the frame 12 via an insertion port 19 which is open on the rear side of the frame 12 in a rectangular shape. A cassette 20 serving as a rectangular container in which a plurality of stacked paper sheets P are loaded is inserted into and/or removed from the insertion port 19 in a direction (forward-backward direction) which is perpendicular to the stack direction of the paper sheets P (up-down direction), such that the paper sheets P can be removably mounted in the mounting unit 13 together with the cassette 20.
Next, the feeding unit 14 is disposed in the frame 12 at a position corresponding to the internal end face of the mounting unit 13. The feeding unit 14 is also provided with a pick-up roller 14a that rotates in response to a driving force of a feed motor, which is not shown. The rotation of the pick-up roller 14a feeds the uppermost paper sheet P of the stacked paper sheets P loaded on the cassette 20, which has been inserted in the mounting unit 13 through the insertion port 19, in a direction away from the insertion port 19 (forward direction).
Further, the separation unit 15 is disposed in the frame 12 at a position opposite the front end of the cassette 20 in a mounted state in the mounting unit 13 in the insertion direction (forward direction). The separation unit 15 is also provided with an inclined plate 21 which forms a rising surface as seen from the mounting unit 13. In the separation unit 15, the paper sheet P which has been fed from the feeding unit 14 is advanced over a separation slope 21a that is formed by the surface of the inclined plate 21 with the leading edge of the paper sheet P abutting the separation slope 21a such that the paper sheet P is separated from the stack and fed downstream toward the transportation unit 16.
As shown in
The separation roller 23 works to separate the paper sheets P which have been sent together without being separated by the separation slope 21a, thereby ensuring that the paper sheets P are fed one by one toward the downstream region where the intermediate transportation rollers 24 are disposed. Each of the intermediate transportation rollers 24 rotates to transport the paper sheet P in a reverse transportation direction (backward direction) which is opposite to the feeding direction from the cassette 20 to the separation unit 15 (forward direction) such that the paper sheet P is transported to the recording unit 17 while being reversed.
Further, the recording unit 17 is disposed in the upper area in the frame 12 as mentioned above and provided with a pair of transportation rollers 25, a recording head 26 and a support member 27 which serves as a support base for the paper sheet P. The recording head 26 is secured to a carriage 29 that is movable in a reciprocating manner along a guide shaft 28 in the width direction (left-right direction) which is perpendicular to the transportation direction of the paper sheet P. The carriage 29 is actuated by drive means which is not shown (for example, a carriage motor) so as to move in a main scan direction (left-right direction) along the guide shaft 28. The position of the carriage 29 in the scan direction is detected by a position detector (encoder) 30 so that the actuating state of the carriage 29 can be controlled.
Once the paper sheet P is fed to the recording unit 17 having the above mentioned configuration, the paper sheet P is transported in a backward direction which is perpendicular to the main scan direction by way of the rotation of a driving transportation roller 32 which constitutes the pair of transportation rollers 25 with a driven transportation roller 31 while being pinched between the transportation rollers 31 and 32, and then fed into a space between the recording head 26 and the support member 27.
The paper sheet P is advanced while being pressed against the support member 27 such that a gap PG is formed relative to the recording head 26. In this state, the recording head 26 moves in the main scan direction (left-right direction) which is the width direction of the paper sheet P in accordance with the movement of the carriage 29. During this movement, a printing operation (a recording operation) is performed by ejecting ink in liquid form through nozzles onto the paper sheet P which is spaced apart from the recording head 26 by the gap PG. The paper sheet P on which the printing operation has been performed is then transported to the discharge unit 18.
The discharge unit 18 has a pair of discharge rollers 33 and a discharge stacker 34. The paper sheet P is transported downstream in the transportation direction (backward direction in
As shown in
Next, the configuration of the cassette 20 will be described below in detail. As shown in
Further, a rear edge guide 42 is also erected on the top of the cassette body 40 so as to control the movement of the paper sheet P in the backward direction. The rear edge guide 42 is slidably movable in the forward-backward direction so as to adjust the position thereof for the length of the paper sheet P in the forward-backward direction loaded on the cassette 20. Moreover, a projection 43 which extends forward is formed on the front face of the cassette body 40 to the right of the center in the left-right direction. The tip (front end) of the projection 43 is bent upward.
Next, the configuration of the damper member 100 will be described below in detail. As shown in
As shown in
The second lever 52c has an intermediate portion in the up-down direction which is bent slightly backward. The lower end of the second lever 52c is configured to be pressed forward by the projection 43 of the cassette 20 when the cassette 20 is mounted in the mounting unit 13. Moreover, a compression coil spring 54 is arranged on the rear surface of the lever receiving section 51 at a position corresponding to the first lever 52b so as to constantly bias the first lever 52b in the backward direction.
As shown in
On the rear surface of the stopper 55, a control surface 55b having a rectangular shape is provided so as to come into contact with the paper sheet P moving in the forward direction, that is, the insertion direction of the cassette 20 when the cassette 20 is inserted into the mounting unit 13, thereby controlling the movement of the paper sheet P. A substantially cylindrical cam 55c which extends in the left-right direction is formed on the front surface of the stopper 55 at a position slightly lower than the center in the up-down direction.
As shown in
The slider 53 includes a base 57 having a rectangular shape, three slide members 57a which extend downward from the underside of the base 57, a cam face constituting member 58 which is arranged on the top of the base 57 at a rear position and an engagement member 59 having a plate shape which is arranged on the top and to the right side of the base 57 so as to engage the lower end of the first lever 52b.
The respective slide members 57a are formed in rectangular shapes that correspond to the respective channels 56a and are slidably inserted into the respective channels 56a. When sliding in the channels 56a, the slide member 57a is subject to resistance of the viscous member (not shown). As a result, in this embodiment, the slider 53 and the slider support 56 serve as a damper.
As shown in
As shown in
The second cam face 62b has an upper half and a lower half. The upper half of the second cam face 62b is inclined at a slightly greater angle than the lower half of the second cam face 62b. Further, for a portion of the first cam face 62c which corresponds to the second cam face 62b, the upper half of the portion of the first cam face 62c is inclined at a slightly greater angle than the lower half of the portion of the first cam face 62c similarly to the second cam face 62b. The distances between the first cam face 62c and each of the press cam face 62a and the second cam face 62b are slightly greater than the outer diameter of the cam 55c and are substantially constant.
The press cam face 62a is inclined relative to a straight line L which extends from a contact point N between the cam 55c and the press cam face 62a to an axis S (rotation center) of the shaft 55a at a greater angle than relative to a reference straight line K (a vertical line in this embodiment) which is perpendicular to a plane parallel to the insertion direction (forward direction) of the cassette 20 when inserted into the mounting unit 13 (a horizontal plane in this embodiment). That is, the angle between the reference straight line K and the press cam face 62a is greater than the angle between the reference straight line K and the straight line L. While the angle between the reference straight line K and the press cam face 62a is generally set to 90 degrees or less (not to exceed 90 degrees), the angle is set to approximately 60 degrees in this embodiment. In addition, the angle between the second cam face 62b and the reference straight line K is smaller than the angle between the press cam face 62a and the reference straight line K.
Next, the operation of the damper member 100 will be described below in detail. As shown in
Then, the lever member 52 resists against a biasing force of the compression coil spring 54 and rotates about the supported shaft 52a which serves as a rotation axis in the counterclockwise direction as seen from the right side. This causes the lower end of the first lever 52b to move forward while extending the tension coil spring 60 against an elastic force of the tension coil spring 60, as shown in
When the paper sheet P moves forward, which is the insertion direction, due to a momentum caused by mounting the cassette 20 in the mounting unit 13, the movement of the paper sheet P is controlled by coming into contact with the control surface 55b of the stopper 55. The impact of the paper sheet P coming into contact with the control surface 55b causes the stopper 55 to rotate about the shaft 55a in a clockwise direction as seen from the right side, thereby causing the cam 55c to press against the press cam face 62a.
Accordingly, as shown in
Accordingly, the horizontal component F1 of the force F that works to move the slider 53 in the forward direction can be reduced, since a substantial part of the force F is allocated as the vertical component F2 to the rigidity of the damper member 100. The impact of the paper sheet P coming into contact with the control surface 55b restrains the movement of the slider 53 in the forward direction, thereby restraining the rotation of the stopper 55. As a consequence, the stopper 55 fully restrains the movement of the paper sheet P.
After the movement of the paper sheet P is restrained by the stopper 55, the slider 53 is pulled forward along the slider support 56 due to the contraction of the tension coil spring 60, thereby gradually starting a sliding movement with resistance of the viscous member (not shown). Then, as shown in
After that, when the slider 53 moves forward due to the contraction of the tension coil spring 60 with resistance of the viscous member (not shown), the cam 55c slides downward on the first cam face 62c, as shown in
When the slider 53 moves forward to maximum due to the contraction of the tension coil spring 60 with the resistance of the viscous member (not shown), the cam 55c slides to the lower end of the first cam face 62c and the stopper 55 becomes inclined at a maximum, as shown in
When the stopper 55 is in the release position, since the control of the movement of the paper sheet P is released, that is, the paper sheet P is allowed to be moved in the forward direction, the movement of the paper sheet P from the cassette 20 to the separation slope 21a is not disturbed by the stopper 55. In contrast, when the slider 53 is in the second position, the engagement member 59 abuts (engages) the lower end of the first lever 52b.
Accordingly, in the ink jet printer 11 according to this embodiment, the stopper 55 rotates from the control position to the release position with a time lag (with a time delay) after the timing when the cassette 20 is mounted in the mounting unit 13. Therefore, the stopper 55 can prevent the paper sheet P from moving in the forward direction during mounting of the cassette 20 into the mounting unit 13. Moreover, it is also possible that the stopper 55 does not disturb the transportation of the paper sheet P during transporting the paper sheet P from the cassette 20 to the separation slope 21a.
In addition, when the cassette 20 is removed in the backward direction from the mounting unit 13 in order to replenish the paper sheets P in the cassette 20 after the paper sheets P in the cassette 20 are used up, the lever member 52 rotates about the supported shaft 52a which serves as the rotation axis in the clockwise direction as seen from the right side by a biasing force of the compression coil spring 54. This causes the lower end of the first lever 52b to press against the engagement member 59 of the slider 53 in the backward direction.
When the slider 53 slidingly moves from the second position to the first position, the cam 55c comes into contact with the lower end the second cam face 62b and moves the second cam face 62b in the upward direction. This causes the stopper 55 to rotate from the release position to the control position. Then, when the cam 55c slides on the second cam face 62b and is guided to the press cam face 62a, the stopper 55 is positioned in the control position and the slider 53 is positioned in the first position.
According to the embodiment mentioned above in detail, the following effects can be achieved.
(1) In the damper member 100, the press cam face 62a of the slider 53 has an inclination relative to the reference straight line K which is greater than that relative to the straight line L. Accordingly, the impact of the paper sheet P coming into contact with the stopper 55 increases the vertical component F2 of the force F which is exerted by the cam 55c on the press cam face 62a, thereby capable of reducing the horizontal component F1 of the force F (the component of the force that moves slider 53 from the first position to the second position). Therefore, the impact of the paper sheet P coming into contact with the stopper 55 can restrain the slider 53 to move from the first position to the second position by the force F exerted by the cam 55c on the press cam face 62a. As a result, the impact of the paper sheet P coming into contact with the stopper 55 can restrain the stopper 55 to rotate from the control position to the release position, thereby enabling the stopper 55 to fully control the movement of the paper sheet P in the forward direction.
(2) In the damper member 100, the angle between the press cam face 62a of the slider 53 and the reference straight line K is set to 90 degrees or less. Therefore, when the slider 53 slidingly moves from the first position to the second position, the cam 55c pressing against the press cam face 62a can smoothly move to the first cam face 62c so as to come into contact with the first cam face 62c.
(3) In the damper member 100, since the press cam face 62a of the slider 53 is formed in a flat shape, variations in shape of the press cam face 62a can be reduced compared with the press cam face 62a formed in a curved shape.
(4) In the damper member 100, the slider 53 includes the second cam face 62b on which the cam 55c is guided to the press cam face 62a when the slider 53 moves from the second position to the first position. When the slider 53 moves from the second position to the first position, the cam 55c slides on the second cam face 62b to the press cam face 62a, therefore, the stopper 55 can smoothly move from the release position to the control position.
(5) In the damper member 100, the angle between the second cam face 62b and the reference straight line K is smaller than the angle between the press cam face 62a and the reference straight line K. Therefore, the amount of rotation of the stopper 55 from the release position to the control position can be obtained with a relatively small amount of movement of the slider 53 from the second position to the first position. This contributes to downsizing of the damper member 100.
(6) In the damper member 100, since the press cam face 62a and the second cam face 62b are continuous, the size of the slider 53 can be reduced and the number of components constituting the slider 53 can be reduced compared with the case where the press cam face 62a and the second cam face 62b are formed spaced from each other. If the press cam face 62a and the second cam face 62b are not continuous, the press cam face 62a and the second cam face 62b need to be formed side by side in left-right direction, or alternatively, two the sliders 53 need to be formed, with one of the sliders 53 having the press cam face 62a and the other of the sliders 53 having the second cam face 62b.
The above-mentioned embodiment can be modified as follows in another embodiment.
As shown in
In the damper member 100, the press cam face 62a of the slider 53 may not necessarily be flat but may be curved.
The ink jet printer 11 may be configured such that the insertion direction of the cassette 20 into the mounting unit 13 may be angled relative to the horizontal plane.
The ink jet printer 11 may be so-called line head printer in which a recording head is provided in a fixed position and ejects ink onto the paper sheet which is transported under the recording head.
Number | Date | Country | Kind |
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2010-146230 | Jun 2010 | JP | national |