Patent Grant
9718632
This application claims priority from Japanese Patent Application No. 2015-146645 filed Jul. 24, 2015. The entire content of the priority application is incorporated herein by reference.
The present disclosure relates to a sheet supply device, and an image forming system including the sheet supply device.
There is conventionally known a sheet supply device that receives a driving force from an image forming apparatus to supply a sheet to the image forming apparatus. In the sheet supply device, the driving force supplied from the image forming apparatus is transmitted to a sheet supply roller and another sheet supply device (hereinafter referred to as a second sheet supply device).
The second sheet supply device receives the driving force from the image forming apparatus through a sheet supply device which is directly assembled to the image forming apparatus (hereinafter referred to as a first sheet supply device), thereby supplying a sheet to the image forming apparatus.
Note that the first sheet supply device and the second sheet supply device are identical to each other in construction. That is, the second sheet supply device can be directly assembled to the image forming apparatus, and the first sheet supply device can receive the driving force from the image forming apparatus through the second sheet supply device to supply a sheet to the image forming apparatus.
However, output gears of the first and second sheet supply devices are rotated upon rotation of a motor provided in the image forming apparatus. That is, the output gear of each of the first and second sheet supply devices is rotated in interlocking relation to the rotation of the motor.
In this case, the driving force is transmitted to the second sheet supply device even when the first sheet supply device supplies a sheet to the image forming apparatus. Thus, unwanted rotation occurs in the output gear of the second sheet supply device, which generates unwanted noise.
In view of the foregoing, it is an object of the disclosure to provide a sheet supply device capable of restraining generation of unwanted noise, the sheet supply device being capable of outputting a driving force to an external device.
In order to attain the above and other objects, according to one aspect, the disclosure provides a sheet supply device configured to be attached to and detached from an image forming apparatus, and configured to receive a driving force from the image forming apparatus to supply a sheet to the image forming apparatus in response to attachment of the sheet supply device to the image forming apparatus. The sheet supply device includes: a main body; a sheet supply roller; an external output gear; a clutch mechanism; a first transmission mechanism; and a second transmission mechanism. The main body is provided with a sheet supply tray on which a sheet is mountable. The sheet supply roller is configured to be in contact with a sheet mounted on the sheet supply tray and configured to rotate to supply the sheet toward the image forming apparatus. The external output gear is configured to output a driving force to an outside. The clutch mechanism is configured to transmit and interrupt the driving force from the image forming apparatus. The first transmission mechanism is configured to transmit the driving force received through the clutch mechanism to the sheet supply roller. The second transmission mechanism is configured to transmit the driving force received through the clutch mechanism to the external output gear.
According to another aspect, the disclosure provides an image forming system including: an image forming apparatus; and a sheet supply device. The image forming apparatus is configured to form an image on a sheet and provided with an output gear configured to output a driving force to an outside. The sheet supply device is configured to be attached to and detached from the image forming apparatus. The sheet supply device is configured to receive the driving force from the image forming apparatus to supply a sheet to the image forming apparatus in response to attachment of the sheet supply device to the image forming apparatus. The sheet supply device includes: a main body; a sheet supply roller; an external output gear; a first transmission mechanism; and a second transmission mechanism. The main body is provided with a sheet supply tray on which a sheet is mountable. The sheet supply roller is configured to be in contact with a sheet mounted on the sheet supply tray and configured to rotate to supply the sheet toward the image forming apparatus. The external output gear is configured to output a driving force to an outside. The clutch mechanism is configured to transmit and interrupt the driving force from the image forming apparatus. The first transmission mechanism is configured to transmit the driving force received through the clutch mechanism to the sheet supply roller. The second transmission mechanism is configured to transmit the driving force received through the clutch mechanism to the external output gear.
The particular features and advantages of the embodiment(s) as well as other objects will become apparent from the following description taken in connection with the accompanying drawings, in which:
An image forming system including an electrophotographic-type image forming apparatus 1 and a sheet supply device 10 according to one embodiment will be described with reference to the accompanying drawings, wherein like parts and components are designated by the same reference numerals to avoid duplicating description.
As shown in
In the following description, arrows indicative of directions in the drawings are for the purpose of facilitating understanding to the embodiment. The disclosure is not limited to the depicted directions. Further, a part or component to which a reference numeral is affixed implies “at least one” part or component, unless otherwise referred to as “a plurality of” and “not less than two”.
The image forming apparatus 1 includes a main casing 3 and an image forming unit 5 provided therein. The image forming unit 5 is of an electrophotographic type in which an image is formed by transferring a developer image onto a sheet. A sheet supply tray 7 is attachable to and detachable from the main casing 3.
At least one sheet can be mounted on the sheet supply tray 7. A sheet supply roller 7A is provided in the main casing 3 for conveying a sheet placed on the sheet supply tray 7 toward the image forming unit 5. An electronic motor M is provided in the main casing 3.
The motor M is adapted to generate a driving force to be supplied to the sheet supply roller 7A. An output gear MG1 is provided at a lower portion of the main casing 3. The output gear MG1 is adapted to output a driving force from the motor M to the sheet supply device 10. One or a plurality of gears MG2 are provided to transmit the driving force from the motor M to the output gear MG1.
The output gear MG1 is rotatable in interlocking relation to the rotation of the motor M. That is, the output gear MG1 is rotated in response to energization of the motor M, and the rotation of the output gear MG1 is stopped in response to de-energization of the motor M.
The sheet supply device 10 is adapted to supply a sheet to the image forming apparatus 1 upon receipt of the driving force from the image forming apparatus 1 through the output gear MG1. The sheet supply device 10 includes a main body, and a sheet supply tray 11 provided in the main body, as shown in
The main body of the sheet supply device 10 is constituted by segments such as a casing and components that are not subjected to de-assembling, assembling, attachment, or detachment by a user during normal use of the sheet supply device 10. Note that the sheet supply tray 11 can be attached to and detached from the casing of the sheet supply device 10.
As shown in
The external output gear 13 is adapted to output the driving force to an external device such as another sheet supply device. The external output gear 13 has a module and the number of teeth identical to those of the output gear MG1.
The clutch mechanism 14 is adapted to intermittently transmit the driving force from the image forming apparatus 1 to the first transmission mechanism 15 and the second transmission mechanism 16 through the output gear MG1. The clutch mechanism 14 is an electromagnetic clutch that intermittently transmits the driving force using an electromagnetic force. In
The first transmission mechanism 15 is adapted to transmit the driving force received from the clutch mechanism 14 to the sheet supply roller 12, as shown in
The first transmission mechanism 15 includes a second clutch mechanism 14A adapted to intermittently transmits the driving force to be transmitted to the sheet supply roller 12. That is, rotation and stopping of the sheet supply roller 12 is controlled by on/off of the second clutch mechanism 14A. The second clutch mechanism 14A is an electromagnetic clutch.
The second transmission mechanism 16 is adapted to transmit the driving force received from the clutch mechanism 14 to the external output gear 13, as shown in
A pivot arm 17 has one longitudinal end portion that is pivotally movably supported to the main body (see a pivot axis O1 in
As shown in
A moment directing in a direction Ms indicated by an arrow in
Therefore, when the first input gear 18 is disengaged from the output gear MG1, that is, when the sheet supply device 10 is not attached to the image forming apparatus 1, a part of the first input gear 18 protrudes from an upper surface 10A of the casing of the sheet supply device 10 as shown in
Upon attachment of the sheet supply device 10 to the image forming apparatus 1 to configure the image forming system, the first input gear 18 and the output gear MG1 are meshedly engaged with each other as shown in
As shown in
A third input gear 20 is supported to the main body of the sheet supply device 10, and is in always meshing engagement with the second input gear 19. The third input gear 20 has a diameter greater than that of the second input gear 19, and the first input gear 18 has a diameter greater than that of the second input gear 19.
As shown in
A transmission gear 21 is locked with the shaft 22, and is rotatable along with the shaft 22. Thus, the transmission gear 21 is positioned coaxially with the third input gear 20. That is, a rotation axis of the transmission gear 21 is coincident with a rotation axis of the third input gear 20.
The transmission gear 21 is adapted to transmit the driving force to the first transmission mechanism 15 and the second transmission mechanism 16. More specifically, the transmission gear 21 is always in meshing engagement with a second transmission gear 23 (
The transmission gear 21 has a diameter different from that of the third input gear 20. More specifically, the diameter of the third input gear 20 is greater than that of the transmission gear 21. The clutch mechanism 14 is accommodated in the third input gear 20 whose diameter is greater than that of the transmission gear 21.
The clutch mechanism 14 includes an exciting coil 14B, a yoke 14C, and a movable segment (armature) 14D. The exciting coil 14B is adapted to induce a magnetic field upon electric power supply. The yoke 14C is made from a ferromagnetic material. The yoke 14C is adapted to aggregate the magnetic field induced by the exciting coil 14B to the movable segment 14D.
The exciting coil 14B and the yoke 14C are connected to the shaft 22, and are rotatable integrally with the rotation of the shaft 22. The movable segment 14D is made from a ferromagnetic material. The movable segment 14D is connected to the third input gear 20 and rotatable integrally with the rotation of the third input gear 20.
Upon electric power supply to the exciting coil 14B, an electromagnetic attraction force is generated between the yoke 14C and the movable segment 14D by the induced magnetic field. Thus, the movable segment 14D is attracted to the yoke 14C as shown in
That is, upon electric power supply to the exciting coil 14B, the driving force is transmitted from the third input gear 20 to the first transmission mechanism 15 and the second transmission mechanism 16 through the clutch mechanism 14. On the other hand, transmission of the driving force is interrupted when the electric power supply to the exciting coil 14B is stopped.
According to the embodiment described above, transmission of the driving force to the first and second transmission mechanisms 15, 16 can be interrupted by the clutch mechanism 14. Accordingly, noise due to operations of the first and second transmission mechanisms 15, 16 can be reduced, and load imparted on the drive source in the image forming apparatus 1 can be reduced.
That is, transmission of the driving force to the first and second transmission mechanisms 15, 16 can be shut off by the clutch mechanism 14 when supply of sheets from the sheet supply device 10 to the image forming apparatus 1 is not performed. Therefore, operations of the first and second transmission mechanisms 15, 16 can be prevented when no sheet is supplied from the sheet supply device 10 to the image forming apparatus 1. Accordingly, unnecessary rotation of gears can be prevented, thereby restraining unnecessary generation of noise and reducing unnecessary load application to the drive source.
Incidentally, if a plurality of sheet supply devices 10 is assembled to the image forming apparatus 1, the clutch mechanism 14 of the sheet supply device 10 which is in direct connection with the image forming apparatus 1 should be shut off. Thus, transmission of the driving force to the second transmission mechanism 16 is interrupted, so that operation of the first and second transmission mechanisms 15, 16 in the remaining sheet supply devices 10 can be prevented.
In the embodiment described above, the clutch mechanism 14 is accommodated in the third input gear 20. However, higher noise reduction effect would be expected if the clutch mechanism 14 is accommodated in the first input gear 18, because the number of gears to rotate in the sheet supply device 10 can be reduced to a minimum.
Still however, provision of the clutch mechanism 14 at the pivot arm 17 or the first input gear 18 is difficult to achieve in view of layout. Consequently, the clutch mechanism 14 should be accommodated in the third input gear 20 or the transmission gear 21. Here, the diameter of the input gear 20 is greater than that of the transmission gear 21, and the clutch mechanism 14 is best accommodated in the third input gear 20.
Assuming that the clutch mechanism 14 is assembled to the first input gear 18, the electromagnetic clutch may be damaged because the clutch mechanism 14 is exposed to an outside. Therefore, assembly of the clutch mechanism 14 to the first input gear 18 is not appropriate. In the embodiment described above, damages to the electromagnetic clutch can be prevented because the clutch mechanism 14 and the second clutch mechanism 14A are covered with the upper surface 10A of the casing as shown in
In the above-described embodiment, the clutch mechanism 14 is accommodated in the third input gear 20. However, the clutch mechanism 14 may be provided at a position coaxial with one of the first input gear 18, the second input gear 19, the third input gear 20, and the transmission gear 21.
In the above-described embodiment, the clutch mechanism 14 is the electromagnetic-type clutch. However, another type of clutch mechanism may be available such that a gear for transmitting the driving force is moved by an electromagnetic solenoid to interrupt transmission of the driving force.
In the above-described embodiment, the first and second transmission mechanisms 15, 16 are provided by gear trains. However, a transmission mechanism including a toothed belt and a drive shaft may be also available.
In the above-described embodiment, the image forming apparatus 1 is the electrophotographic-type device. However, an ink-jet type image forming apparatus may be also available in which minute ink droplets are ejected onto a sheet to form an image.
While the description has been made in detail with reference to the embodiments thereof, it would be apparent to those skilled in the art that many modifications and variations may be made therein without departing from the spirit of the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2015-146645 | Jul 2015 | JP | national |
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| 5678814 | Yokoyama | Oct 1997 | A |
| 8657278 | Ozeki | Feb 2014 | B2 |
| 8672315 | Goto | Mar 2014 | B2 |
| 20130001855 | Ozeki | Jan 2013 | A1 |
| 20130127107 | Goto | May 2013 | A1 |
| Number | Date | Country |
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| 62079139 | Apr 1987 | JP |
| H04-169432 | Jun 1992 | JP |
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| 2013-010611 | Jan 2013 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20170022019 A1 | Jan 2017 | US |
