1. Technical Field
The present invention relates to a feed device such as a paper feed device and a recording device such as an ink jet printer including the feed device.
2. Related Art
A known recording device such as a printer includes a paper feed device (feed device) for automatically feeding paper to a location facing a recording head (recording unit) while separating a plurality of sheets of paper loaded one by one in a stacked state so as to continuously perform recording with respect to the plurality of sheets of paper (sheet members) (for example, JP-A-8-91612).
The feed device of JP-A-8-91612 includes a paper feed cassette (loading unit) in which a plurality of sheets of paper is loaded in a stacked state, a paper feed roller (delivery member) which rotates while in contact with the uppermost sheet of paper out of the sheets loaded in the stacked state and delivers the uppermost sheet in a feed direction using frictional force with the uppermost paper, and a gate member for preventing double feed of the uppermost sheet of paper and the underlying sheet of paper in the feed direction.
In detail, this gate member is configured such that one end side thereof is oscillatorily supported as a fulcrum and the other end side thereof is in contact with the outer circumferential surface of the paper feed roller due to the energizing force of a predetermined compression spring. In addition, an inclined surface is provided in the other end side of the gate member at a location so that the front end of the paper continuously delivered by the paper feed roller may collide therewith. If the front end of the paper delivered by the paper feed roller in the feed direction collides with the inclined surface, the gate member of which the inclined surface is pressed by the paper oscillates against the energizing force of the compression spring in a direction separating from the outer circumferential surface of the paper feed roller and thus a gap is formed through which only a single sheet of paper passes between the paper feed roller and the gate member. Accordingly, only the uppermost sheet of paper is fed through the gap in the feed direction. At this time, if the uppermost sheet of paper and the underlying sheet of paper are double fed by friction force therebetween, the double feed of the sheet of paper underlying the uppermost sheet of paper is prevented by the inclined surface of the gate member.
However, in the paper feed device of JP-A-8-91612, if the friction force generated between the uppermost sheet of paper and the underlying sheet of paper is increased due to variation in the surrounding environment (temperature, humidity or the like), the underlying sheet of paper may be double fed over the inclined surface of the gate member when the uppermost sheet of paper is fed.
An advantage of some aspects of the invention is that it provides a feed device and a recording device capable of efficiently suppressing double feed of the sheet member underlying an uppermost sheet member when the uppermost sheet member is fed from sheet members loaded in a stacked state.
According to an aspect of the invention, there is provided a feed device including: a loading unit in which a plurality of sheet members is loaded in a stacked state; a delivery member which performs a feed operation in a state in which a contact surface thereof is in contact with an uppermost sheet member of the sheet members loaded on the loading unit and delivers the sheet member in a feed direction using friction force with the uppermost sheet member as the feeding force; a gate member which is configured to move in a direction to and from the contact surface of the delivery member and has an inclined surface with which the front end of the sheet member delivered by the delivery member collides with; and a gate energizing member which energizes the gate member in a direction approaching the contact surface of the delivery member, wherein, the uppermost sheet member is delivered by the delivery member such that the front end thereof collides with the inclined surface of the gate member, and a gap is formed through which only the uppermost sheet member passes between the delivery member and the gate member by moving the gate member against energizing force of the gate energizing member in the direction separating it from the delivery member, and wherein a pressing force applying unit is included which applies a pressing force along the stacked direction of the sheet members at an upstream side of the inclined surface on the feed path of the sheet members to the sheet member underlying the uppermost sheet member over the uppermost sheet member after a portion of the uppermost sheet member passes through the gap.
By this configuration, when the uppermost sheet member of the sheet members loaded in the stacked state is fed, after a portion of the uppermost sheet member passes through the gap, the pressing force applying unit applies the pressing force along the stacked direction of the sheet members to the sheet member underlying the uppermost sheet over the uppermost sheet member at the upstream side of the inclined surface on the feed path of the sheet members. Therefore, since it will be harder for the sheet member underlying the uppermost sheet member to get over the inclined surface due to the pressing force of the pressing force applying unit, it is possible to easily separate the uppermost sheet member and the sheet member underlying the uppermost sheet member. As a result, when the uppermost sheet member is fed, it is possible to efficiently suppress the double feed of the sheet member underlying the uppermost sheet member.
In the feed device of the invention, the pressing force applying unit may include a displacement member which is displaced between a pressing position where the sheet member underlying the uppermost sheet member is pressed and a non-pressing position where the sheet member is not pressed.
By this configuration, when the uppermost sheet member is fed, after the portion of the uppermost sheet member passes through the gap, the displacement member is displaced from the non-pressing position to the pressing position, such that the double feed of the sheet member underlying the uppermost sheet member can be efficiently suppressed.
In the feed device of the invention, the displacement member may include a rotary member which is rotated and displaced between the pressing position and the non-pressing position.
By this configuration, since the displacement member includes the rotary member, it is possible to reduce the space necessary for displacing the displacement member between the pressing position and the non-pressing position, compared with the case where the displacement member includes a member which is linearly reciprocated between the pressing position and the non-pressing position.
In the feed device of the invention, the rotary member may include a first arm engaged with the sheet member at a downstream side of the inclined surface on the feed path of the sheet member at the non-pressing position, and a second arm applying pressing force at the pressing position to the sheet member underlying the uppermost sheet member before feeding.
By this configuration, the rotary member is rotated and displaced from the non-pressing position to the pressing position by the engagement of the uppermost sheet member and the first arm such that the pressing force can be applied by the second arm to the sheet member underlying the uppermost sheet member before feeding.
The feed device of the invention may further include an energizing member for energizing the rotary member to the non-pressing position, and, when a portion of the uppermost sheet member is engaged with the first arm, the rotary member may be rotated and displaced against the energizing force of the energizing member from the non-pressing position to the pressing position.
By this configuration, when the portion of the uppermost sheet paper is engaged with the first arm, it is possible to rotate and displace the rotary member from the non-pressing position to the pressing position against the energizing force of the energizing member. In addition, when the uppermost sheet paper is not engaged with the first arm, it is possible to rotate and displace the rotary member from the pressing position to the non-pressing position by the energizing force of the energizing member.
In the feed device of the invention, the roller, which is rotated by the feeding of the sheet member, may be provided on at least one of the contact portion of the first arm with the sheet member and the contact portion of the second arm with the sheet member.
By this configuration, when the sheet member is fed, even when either the first arm and the second arm is brought into contact with the sheet member, it is possible to reduce the friction resistance force applied from either the first arm and the second arm to the sheet member, by rotating the roller which is in contact with the sheet member. Thus, it is possible to smoothly feed the sheet member.
According to another aspect of the invention, there is provided a recording device including: the feed device according to claim 1; and a recording unit which performs a recording process with respect to the sheet member fed by the feed device.
By this configuration, the same effects as described above can be obtained.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
Hereinafter, an ink jet printer (hereinafter, referred to as a “printer”) which is implemented as a recording device of the invention will be described with reference to the accompanying drawings. In the following description, terms “front-and-rear direction”, “left-and-right direction” and “up-and-down direction” respectively indicate directions denoted by arrows of the drawings.
As shown in
A carriage 18 reciprocally moving in the main scan direction (the left-and-right direction of
As shown in
At the front side in the vicinity of the lower end of the hopper 15 located at the paper feed position, a paper feed roller 23, which functions as a delivery member and has a substantially D-shape in a side view, is supported on a rotary shaft 24 which extends in the left-and-right direction and is provided in the main body 12 (see
The width of the delivery portion 25 in the left-and-right direction is larger than that of the separation portions 26, and the outer circumferential surface of the delivery portion 25 and the outer circumferential surfaces of the separation portions 26 are flush with each other. The paper feed roller 23 is rotated by rotary driving of the rotary shaft 24 so as to perform the feed operation of the paper P. The outer circumferential surface of the paper feed roller 23 includes a circumferential surface 23a which is a contact surface having a radius of a distance R1 from an axial center C of the rotary shaft 24 and a flat surface 23b separating from the axial center C of the rotary shaft 24 by a distance R2, and the distance R1 is set to be larger than the distance R2.
That is, the distances R1 and R2 are set such that the circumferential surface 23a is brought into contact with the paper P and the flat surface 23b is not brought into contact with the paper P, when the paper feed roller 23 is rotated in a state in which the hopper 15 is disposed at the paper feed position. In a state in which the circumferential surface 23a is brought into contact with the paper P, the paper P is pressed into contact with the circumferential surface 23a by the energizing force of the compression spring 22.
The friction force with the paper P, when the paper feed roller 23 is rotated in a state in which the circumferential surface 23a of the delivery portion 25 and the paper P are in contact with each other, is set to be larger than the friction force between the stacked sheets of paper P. In contrast, the friction force with the paper P, when the paper feed roller 23 is rotated in a state in which the circumferential surface 23a of each of the separation portions 26 and the paper P are in contact with each other, is set to be smaller than the friction force between the stacked sheets of paper P.
Accordingly, when the paper feed roller 23 is rotated in a state of being in contact with the paper P, the energizing force of the compression spring 22 becomes a vertical resisting force and the friction force generated between the circumferential surface 23a of the delivery portion 25 and the paper P becomes the feeding force, such that the paper P is delivered by the delivery portion 25. In this case, since the friction force generated between the circumferential surface 23a of each of the separation portions 26 and the paper P is smaller than the friction force generated between the sheets of paper P, the feeding force for delivering the paper P is not generated in the separation portions 26.
As shown in
Arm members 28, which are supported so that they can oscillate by the base portion 21 with an axial portion 27 whose lower end side extends in the left-and-right direction, are obliquely disposed at positions corresponding to both the separation portions 26 in the insides of both the guides 21a in the base portion 21, and gate members 29 are attached to the upper end sides of both the arm members 28 so as to individually correspond to both the separation portions 26. In the gate members 29, inclined surfaces 29a are formed which protrude higher than the guides 21a in the base portion 21 such that the paper P delivered from the paper feed tray 14 collides therewith at a predetermined angle.
Torsion coil springs 30 are mounted on convex portions 28a extending outward in the vicinities of the upper ends of the arm members 28. One end of each of the torsion coil springs 30 is locked to a locking portion (not shown) provided in the base portion 21 and the other end thereof is locked to a locking portion (not shown) provided in each of the gate members 29.
The gate members 29 are not in contact with the separation portions 26 when facing the vicinities of the centers of the flat surface 23b of the separation portions 26 in the paper feed roller 23, but are rotated in a clockwise direction of
When the paper P is fed, as shown in
At this time, the gate members 29 are moved from the state of
That is, when the uppermost sheet of paper P delivered by the delivery portion 25 of the paper feed roller 23 collides with the inclined surfaces 29a, the contact angle between the inclined surfaces 29a and the paper P or the energizing force of the torsion coil springs 30 is set such that a gap, through which only a single sheet of paper P can pass, is formed between the separation portions 26 of the paper feed roller 23 and the gate members 29.
Meanwhile, the paper P underlying the uppermost sheet of paper P does not have a feeding force capable of moving the gate members 29 against the energizing force of the torsion coil springs 30 when colliding with the inclined surfaces 29a of the gate members 29. Accordingly, even when the underlying sheet of paper P is pulled along with the uppermost sheet of paper P delivered by the delivery portion 25 of the paper feed roller 23 by the friction force, the underlying sheet of paper P is prevented from being fed due to the collision with the inclined surfaces 29a of the gate members 29 and thus is separated from the uppermost sheet of paper P.
As shown in
A rotary member 33, which is a displacement member functioning as a pressing force applying unit, is supported on the shaft 32 so as to be rotated around the shaft 32. The rotary member 33 includes a first arm 34 extending from the shaft 32 toward the front oblique lower side thereof and a second arm 35 extending from the shaft 32 toward the rear oblique upper side thereof, and the length of the first arm 34 is shorter than that of the second arm 35. One end of the first arm 34 and one end of the second arm 35 are connected to each other in a support portion of the shaft 32, and the angle between the first arm 34 and the second arm 35 is always constantly maintained.
A roller 34a, which rotates around an axial line extending in the left-and-right direction, is pivotably supported on the front end (lower end) of the first arm 34, and approximately half of the roller 34a is inserted into a concave portion 21c provided at the front side of the right guide 21a. Accordingly, the first arm 34 can be engaged with the paper P fed at the downstream side of the inclined surfaces 29a of the gate members 29 on the feed path of the paper P.
Meanwhile, a roller 35a, which rotates around an axial line extending in the left-and-right direction, is pivotably supported on the front end (upper end) of the second arm 35, and the roller 35a faces the lower end of the paper P loaded in the paper guide 17 in the stacked state before feeding. One end of a coil spring 36 functioning as an energizing member is attached to the upper surface of the front end of the second arm 35, and the other end of the coil spring 36 is fitted into the overhang portion 31.
The rotary member 33 is rotated and displaced between a non-pressing position (position shown in
Next, the operation of the auto paper feed device 13 having the above-described configuration will be described with reference to
In a reset state shown in
When the rotation of the rotary shaft 24 is started and the paper feed roller 23 is rotated in the clockwise direction of
Then, as shown in
When the paper feed roller 23 is continuously rotated, as shown in
Then, since the front end of the uppermost sheet of paper P slides between the concave portion 21c of the guide 21a and the roller 34a of the first arm 34 due to the rotating the roller 34a, the first arm 34 is pushed up by the uppermost sheet of paper P. Accordingly, the rotary member 33 is rotated around the shaft 32 in the clockwise direction of
That is, since the paper P underlying the uppermost sheet of paper P is pressed by the roller 35a of the second arm 35 at the upstream side of the inclined surfaces 29a of the gate members 29 on the feed path of the paper P, it is even harder for the underlying sheet of paper P to get over the inclined surfaces 29a and thus the underlying sheet of paper P is properly prevented from being fed (double fed) together with the uppermost sheet of paper P. At this time, since the rotary member 33 is in contact with the uppermost sheet of paper P in the roller 34a of the first arm 34 and the roller 35a of the second arm 35, both the rollers 34a and 35a are rotated by the feed of the uppermost sheet of paper P. Accordingly, since friction resistance, which is applied from the rotary member 33 in which the uppermost sheet of paper P is located at the pressing position when the uppermost sheet of paper P is fed, is reduced, the smooth feeding state of the uppermost sheet of paper P is maintained.
Thereafter, the uppermost sheet of paper P is fed to the recording head 19 by the feeding force based on the rotation of the paper feed roller 23. When the uppermost sheet of paper P is fed to the recording head 19 such that the uppermost sheet of paper P and the roller 34a of the first arm 34 are separated from each other, the rotary member 33 is rotated and displaced from the pressing position to the non-pressing position by the energizing force of the coil spring 36.
According to the above-described embodiment, the following effects can be obtained.
(1) In the auto feed device 13, when the uppermost sheet of paper P is fed from the sheets of paper P loaded in the stacked state, the rotary member 33 is rotated and displaced from the non-pressing position to the pressing position by the engagement between the uppermost sheet of paper P and the first arm 34 after the front end of the uppermost sheet of paper P passes through the gap between the circumferential surface 23a of the separation portions 26 of the paper feed roller 23 and the gate members 29. Thus, it is possible to apply the pressing force along the stacked direction of the sheets of paper P to the paper P underlying the uppermost sheet of paper P over the uppermost sheet of paper P by the second arm 35. Therefore, since it is hard for the paper P underlying the uppermost sheet of paper P to get over the inclined surfaces 29a of the gate members 29 due to the pressing force of the second arm 35 (rotary member 33), it is possible to easily separate the uppermost sheet of paper P and the paper P underlying the uppermost sheet of paper P. As a result, when the uppermost sheet of paper P is fed, it is possible to efficiently suppress the double feed of the paper P underlying the uppermost sheet of paper P.
(2) In the auto feed device 13, since the displacement member is composed of the rotary member 33, it is possible to reduce the space necessary for displacing the displacement member between the pressing position and the non-pressing position, compared with the case where the displacement member is linearly reciprocated between the pressing position and the non-pressing position.
(3) The auto feed device 13 includes the coil spring 36 for energizing the rotary member 33 in the direction of its non-pressing position. Thus, when the front end of the uppermost sheet of paper P is engaged with the first arm 34, it is possible to rotate and displace the rotary member 33 from the non-pressing position to the pressing position against the energizing force of the coil spring 36 using the feeding force of the uppermost sheet of paper P. In addition, when the uppermost sheet of paper P is not engaged with the first arm 34, it is possible to rotate and displace the rotary member 33 from the pressing position to the non-pressing position by the energizing force of the coil spring 36.
(4) The rollers 34a and 35a, which rotate due to the feeding of the uppermost sheet of paper P, are provided in the contact portion of the first arm 34 with the uppermost sheet of paper P and the contact portion of the second arm 35 with the uppermost sheet of paper P. Thus, when the uppermost sheet of paper P is fed, the rotary member 33 is rotated and displaced from the non-pressing position to the pressing position. Accordingly, even when the first arm 34 and the second arm 35 are brought into contact with the uppermost sheet of paper P, it is possible to reduce the friction resistance force applied from the first arm 34 and the second arm 35 to the uppermost sheet of paper P. That is, even when the first arm 34 and the second arm 35 are brought into contact with the uppermost sheet of paper P, since the roller 34a and the roller 35a are rotated by the feeding of the uppermost sheet of paper P, it is possible to maintain the smooth feed state of the uppermost sheet of paper P without interfering the feed of the uppermost sheet of paper P.
(5) When the rotary member 33 is located at the non-pressing position, since the concave portion 21c into which the roller 34a of the first arm 34 is inserted is provided in the guide portion 21a, it is possible to increase the rotational range of the rotary member 33 by the depth of the concave portion 21c.
In addition, the above-described embodiment may be changed as follows.
At least one of the rollers 34a and 35a of the arms 34 and 35 may be omitted. In this case, the portions of the arms 34 and 35 with contact with the uppermost sheet of paper P preferably have a shape in which they easily slide on the uppermost sheet of paper P (for example, a drum shape, a spherical shape or a flat shape).
Instead of the coil spring 36, a rubber or torsion coil spring may be used as an energizing member.
A sensor for detecting that the front end of the uppermost sheet of paper P passes through the gap between the circumferential surface 23a of the separation portions 26 in the paper feed roller 23 and the gate members 29 may be provided, and an actuator which reciprocally moves between the pressing position and the non-pressing position based on the signal output from the sensor may be used as the displacement member instead of the rotary member 33.
A sensor may be provided for detecting that the front end of the uppermost sheet of paper P has passed through the gap between the circumferential surface 23a of the separation portions 26 of the paper feed roller 23 and the gate members 29, and a blower for blowing air so as to apply the pressing force along the stacked direction of the sheets of paper P to the paper P underlying the uppermost sheet of paper P before feeding over the uppermost sheet of paper P based on the signal output from the sensor may be used as the pressing force applying unit instead of the displacement member.
The concave portion 21c provided in the guide 21a may be omitted.
Instead of the paper feed roller 23, an endless transfer belt which circumferentially moves may be employed, and the paper feed operation may be performed by the circumferential movement of the endless transfer belt.
In the paper feed roller 23, the separation portions 26 may be omitted. In this case, the gate members 29 need to be configured to be in contact with the delivery portion 25.
In the paper feed roller 23, the delivery portion 25 and the separation portions 26 may be separately configured. In this case, the delivery portion 25 and the separation portions 26 need to be configured to be synchronously rotated by the rotation and the driving of the rotary shaft 24.
The number of rotary members 33 may be two or more.
The paper feed roller 23 may be configured in a circular shape in a side view.
In the paper feed roller 23, the separation portion 26 may be disposed on the center thereof in the axial direction and the delivery portions 25 may be disposed on both sides of the separation portion 26 in the axial direction.
The movement of the gate members 29 is not limited to rotation, and, for example, reciprocal movement may be used using a slider with a coil spring interposed therebetween.
Instead of the paper P, a plastic film may be used as a sheet member.
Number | Date | Country | Kind |
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2008-211654 | Aug 2008 | JP | national |