JP7630939B2 - Coupling mechanism and feeding device - Google Patents

Description

This relates to a paper feeder that feeds sheets to an image forming device such as a copier or printer.

Conventionally, there has been known a paper feed device that feeds sheets to an image forming section of an image forming device such as a copier or printer. A typical paper feed device is provided with a stacking section in which sheets are stacked, and a paper feed means that feeds the sheets from this stacking section. Some stacking sections are provided with a paper feed cassette that can store around 100 sheets, while others are provided with a storage unit that can store a large volume of sheets, amounting to several thousand sheets.

The paper feed means includes a feed roller that feeds the sheets from the stacking section, a feed roller that feeds the fed sheets, and a separation member that presses against the feed roller to separate the sheets into individual sheets. The cassette or storage case can be pulled out from the device body to store the sheets. Conventional paper feeders that include a cassette or storage case are known to include a stacking section provided in the cassette or storage case and a lifting mechanism that raises and lowers the stacking section. The lifting mechanism includes four wires that suspend the four sides of the stacking section, a winding pulley that winds up the four wires, a lifting motor that rotates the winding pulley, and a drive transmission mechanism that transmits the drive of the lifting motor to the winding pulley. The lifting mechanism drives the lifting motor in the forward direction, causing the winding pulley to rotate and wind up the wires, thereby raising the stacking section. On the other hand, when the lifting motor is driven in the reverse direction, the winding pulley rotates in the opposite direction, the wire is unwound from the winding pulley, and the loading section is lowered (for example, Patent Document 1).

In the paper feeder as described above, there is a coupling mechanism that transmits or does not transmit the power of the lifting motor to the take-up pulley by connecting or separating the first and second drive transmission members as a drive transmission mechanism that raises or lowers the stacking unit by the power of the lifting motor (for example, Patent Document 2). This coupling mechanism is configured to transmit or not transmit the power of the lifting motor to the lifting mechanism depending on the state of mounting and drawing out the cassette or storage unit to the device main body. The coupling mechanism generally couples the first and second drive transmission members by engaging multiple recesses formed in the first drive transmission member with multiple protrusions formed in the second drive transmission member, and transmits the power of the lifting motor to the lifting mechanism. Also, it is configured not to transmit the power of the lifting motor to the lifting mechanism by separating the first and second drive transmission members. The coupled recess and protrusion rotate with one side of the recess abutting against one side of the protrusion to transmit the power. Therefore, when the lift motor is stopped and the first drive transmission member and the second drive transmission member are separated, the recess of the first drive transmission member and the protrusion of the second drive transmission member are in a position to engage with each other.

JP 2017-31985 A JP 2004-51255 A

However, if the first drive transmission member and the second drive transmission member are slightly misaligned from their mating position after being separated, the top of the recess of the first drive transmission member and the top of the protrusion of the second drive transmission member will interfere with each other, and this interference may cause the first drive transmission member and the second drive transmission member to fail to connect or may damage each member.

The present invention was made in consideration of the above problems, and aims to provide a coupling mechanism that can reliably connect a first drive transmission member and a second drive transmission member.

In order to achieve the above object, a first invention provides a coupling mechanism for transmitting power from a drive source to a driven body, the coupling mechanism comprising a first transmission member, a second transmission member which is connected to and separated from the first transmission member, a shaft member which supports the second transmission member, a moving means which moves the second transmission member along the shaft member when the first transmission member and the second transmission member are separated, a regulating member which is provided at a predetermined position on the shaft member and which regulates the movement of the second transmission member by the moving means, and a rotating member which is provided on the second transmission member and which abuts against the regulating member to rotate the second transmission member a predetermined amount .

A second invention relates to a paper feeder including a storage case that can be pulled out relative to a device body, a loading tray that is provided in the storage case and on which sheets are loaded, a lifting mechanism that lifts the loading tray, a drive motor that can rotate forward and backward for driving the lifting mechanism, and a drive transmission means that transmits the power of the drive means to the lifting mechanism, the drive transmission means having a coupling mechanism that transmits the power of the drive means to the lifting mechanism when the storage case is attached to the device body and does not transmit the power of the drive means to the lifting mechanism when the storage case is pulled out from the device body, The coupling mechanism has a first transmission member, a second transmission member that connects to the first transmission member when the storage cabinet is attached to the device body and that moves away from the first transmission member when the storage cabinet is pulled out from the device body, and a rotation means that rotates the second transmission member a predetermined amount when the second transmission member and the first transmission member move away from each other. The coupling mechanism transmits the forward rotation of the drive motor to the lifting mechanism when the storage cabinet is attached to the device body, and the lifting mechanism lifts the loading tray with the forward rotation of the drive motor transmitted from the coupling mechanism .

According to the first and second aspects of the present invention, when the second transmission member and the first transmission member separate, the second transmission member is rotated to a position where they can be automatically connected, thereby reliably connecting the first drive transmission member and the second drive transmission member.

1 is a schematic cross-sectional view showing the configuration of an image forming system according to the present invention; FIG. 4 is a diagram showing a state in which a storage case is pulled out in the paper feeder according to the present invention; FIG. 4 is a perspective view showing a lifting mechanism for a loading section according to the present invention. FIG. 2 is a perspective view showing a lift motor and a drive transmission mechanism according to the present invention. 10A and 10B are schematic diagrams showing the state of the lifting motor and the drive transmission mechanism when the storage cabinet according to the present invention is pulled out and installed; FIG. 2 is a perspective view showing a state of the coupling mechanism according to the present invention. 1A and 1B are a combined sectional view and a sectional perspective view illustrating a configuration of a coupling mechanism according to the present invention. 11A and 11B are schematic diagrams illustrating another embodiment of a coupling mechanism according to the present invention.

[Image forming system]
1 is a diagram showing the overall configuration of an image forming system equipped with a paper feeder. As shown in the diagram, the image forming system is composed of an image forming device 1 that prints images on sheets, a document reading device 2 that reads documents, a document feeder 3 that transports sheets to a reading section of the document reading device 2, a paper feeder 4 that supplies sheets to the image forming device 1, and a sheet stacking device 5 that is connected to a paper discharge port of the image forming device 1 and stacks sheets discharged from the image forming device 1.

The image forming device 1 is equipped with two paper feed cassettes 6a and 6b that can store approximately 100 sheets. A sheet is taken out from either one of the two paper feed cassettes 6a and 6b or the paper feed device 4, image data transferred from the document reading device 2 is printed on the taken-out sheet, and the sheet is discharged to the sheet stacking device 5 by a pair of paper discharge rollers 10.

The image forming device 1 performs electrostatic printing and is equipped with a beam projector 12 that forms an electrostatic latent image on a photosensitive drum 11, a developer 13 that applies toner ink to the electrostatic latent image, and a transfer charger 14. The image ink formed on the photosensitive drum 11 is transferred to a sheet by the transfer charger 14, and the image on the sheet is heated and fixed by a fixing roller 15 located downstream, and the sheet is then transported to the sheet accumulation device 5.

The paper feed device 4 has a storage section (storage cabinet) 30 that can store 3,000 sheets, which is more than the paper feed cassettes 6a and 6b, and supplies sheets to the image forming device 1 one by one in accordance with a paper feed command from the image forming device 1.

The document reading device 2 has a first platen 16 and a second platen 17 made of transparent glass arranged side by side horizontally on the top of the device. The first platen 16 is used to read documents that are manually placed, and is formed to the maximum size of a document that can be used. The second platen 17 is used to read documents that move at a predetermined speed.

Inside the image reading device 2, there are first and second reading carriages 18 and 19, and a photoelectric conversion means having a condenser lens 20 and a photoelectric conversion element 21 (CCD). The first and second reading carriages 18 and 19 are driven by a carriage motor (not shown) and move back and forth in the sub-scanning direction below the first platen 16. The first reading carriage 18 is provided with a lamp that irradiates light toward the document and a mirror that reflects the light reflected from the document, and the second reading carriage 19 is provided with two mirrors that guide the light from the mirror of the first reading carriage 18 to the condenser lens 20 and the photoelectric conversion element 21. The first and second reading carriages 18 and 19 move to irradiate light onto the document set on the first platen 16, and the reflected light from the document is photoelectrically converted by the photoelectric conversion element 21 to read the document. The image data of the document read by the photoelectric conversion element 21 is transmitted as an image signal to the beam projector 12 of the image forming device 1.

The document feeder 3 passes the document set in the paper feed tray 22 through the second platen 17 by the sheet transport mechanism 24 and discharges the document onto the discharge tray 23. When the document feeder 3 reads a document passing over the second platen 17, the first and second reading carriages 18 and 19 are stationary below the second platen 17 and read the moving document.

The sheet feeder 4 includes a storage case 30 that is pulled out to set sheets, and a sheet feed mechanism 31 that feeds sheets from the storage case 30. The storage case 30 includes a stacking section 32 on which sheets are stacked and which moves up and down, a trailing end regulating plate 36 that is slidable in the sheet feed direction and regulates the trailing end of the sheets on the stacking section 32, a pair of side regulating plates 35 that are slidable in the sheet width direction perpendicular to the sheet feed direction and regulate both ends of the sheets on the stacking section 32 in the sheet width direction, and a lifting mechanism 37 that lifts and lowers the stacking section 32.

The paper feed mechanism 31 includes a feed roller 40 that feeds a sheet in the storage chamber 30, a feed roller 41 that feeds the sheet fed by the feed roller 40, a separation roller 42 that is pressed against the feed roller 41 to separate the sheet fed by the feed roller 40, and a pair of transport rollers 43 that supply the sheet fed by the feed roller 41 to the image forming device 1.
The feed roller 40 comes into contact with the upper surface of the topmost sheet moved to the feed position by the stacking unit 32, and feeds out the sheet on the stacking unit 32. The fed sheet is separated into individual sheets by a feed roller 41 and a separation roller 42, and sent to a conveying roller pair 43. The conveying roller pair 43 then supplies the sheets to the image forming apparatus 1 one by one in sequence.

2 is a diagram showing a state in which the storage 30 is pulled out from the housing (sheet feeder main body) 4a of the sheet feeder 4. On both sides of the sheet feed direction of the storage 30, a pair of slide rails 24, 25 are provided to support the storage 30 so that it can slide in the front-rear direction perpendicular to the sheet feed direction. The storage 30 slides along the slide rails to an attached position where it is attached to the housing 4a of the sheet feeder 4 and a pulled-out position where it is pulled out from the housing 4a of the sheet feeder 4. Then, the storage 30 is moved from the attached position to the pulled-out position, and sheets are loaded on the stacking section 32 in the pulled-out state in the pulled-out position as shown in FIG. 2.
The slide rail is a typical slide rail, and is composed of an inner rail attached to the storage 30 and an outer rail attached to the housing 4a.

As shown in FIG. 2, the loading section 32 is composed of a loading tray 32a and an auxiliary tray 32b. The loading tray 32a is cut out at a portion where a rear end regulating plate 36 that regulates the rear end of the loaded sheets slides. In addition, both side portions where a pair of side regulating plates 35 that regulate both ends of the sheets in the sheet width direction perpendicular to the sheet feed direction move are also cut out. The auxiliary trays 32b are disposed in the cutout portions on both sides of the sheet width direction of the main tray 32a. Each auxiliary tray 32b is attached to the side regulating plate 35 so that it can move in the vertical direction. As a result, the auxiliary tray 32b moves in the sheet width direction in conjunction with the movement of the side regulating plate. In addition, the auxiliary tray 32b moves in the vertical direction in conjunction with the lifting and lowering operation of the loading tray 32a. The loading tray 32a is supported by the first and second stays 33 and 34. The first stay 33 supports the upstream end of the loading tray 32a, and the second stay 34 supports the upstream end of the loading tray 32a.

[Loading tray lifting mechanism 37]
Next, a description will be given of the lifting mechanism 37 of the loading section 32 in the storage 30. FIG.

The lifting mechanism 37 of this embodiment is a wire-type lifting mechanism 37 that includes four wires 55a-55d that suspend both ends of the first and second stays 33, 34 that support the upstream and downstream sides of the stacking tray 32a in the sheet feeding direction, multiple suspension pulleys 52a-52d around which the four wires 55a-55d are respectively hung, and two winding pulleys 53a, 53b that are provided on both sides of the same winding shaft 56 and wind the four wires 55a-55d.

Each wire 55a-55d has one end fixed to the winding pulleys 53a, 53b, and the other end attached to the end of each stay 33, 34 via hanging pulleys 52a-52d supported on the frame of the storage cabinet 30. In other words, the four wires 55a-55d support the four corners of the loading tray 32a, and are wound up by the forward rotation of the winding pulleys 53a, 53b, thereby lifting the loading section 32 including the loading tray 32a. In addition, the four wires 55a-55d are unwound by the reverse rotation of the winding pulleys 53a, 53b, thereby lowering the loading section 32 including the loading tray 32a.

The lifting mechanism 37 further includes a drive unit including the lifting motor MT3, which is a drive source, and a drive transmission mechanism 38 including multiple gears Z1-Z6 and a timing belt TB1 that transmit the drive of the lifting motor MT3 to the winding pulleys 53a, 53b. The lifting motor MT3 is a motor that can rotate forward and backward. Hereinafter, forward rotation of the lifting motor MT3 rotates the winding pulleys 53a, 53b forward in the winding direction of the wires 55a-55d, and reverse rotation of the lifting motor MT3 rotates the winding pulleys 53a, 53b backward in the unwinding direction of the wires 55a-55d. In this embodiment, the drive force (power) for raising the loading section 32 is referred to as the first drive force, and the drive force for the lifting motor MT3 to lower the loading section 32 is referred to as the second drive force.

As shown in Figures 2 and 3, the drive unit including the lift motor MT3 is pulled out from the housing 4a together with the storage 30, and is configured to be supplied with power even when pulled out. In this embodiment, a pulse motor is used as the lift motor MT3, and the number of drive pulses of the pulse motor is counted to control the amount of lift or lowering of the loading section 32.

[Drive transmission mechanism]
Fig. 4 is a perspective view of the drive unit, and Fig. 5(a) and (b) are schematic diagrams of the drive unit. As shown in Fig. 4 and Fig. 5, the drive transmission mechanism 38 of the drive unit includes a timing belt TB1, a drive pulley 58, an input pulley (first drive transmission member) 59, a one-way clutch OW1, a coupling member (second drive transmission member) 60, a biasing spring (moving means) SP, a drive gear Z1, idler gears Z2 to Z5, and a winding gear Z6. The input pulley 59, the coupling member 60, and the biasing spring SP form a coupling mechanism 39 for transmitting and blocking the forward rotation of the lift motor MT3 to the winding pulleys 53a and 53b of the lift mechanism 37.

The input pulley 59 is provided on the rotating shaft SF1 and is connected to a drive pulley 58 attached to the output shaft of the lift motor MT3 via a timing belt TB1. Therefore, the input pulley 60 always rotates in conjunction with the output shaft of the lift motor MT3. The rotation direction of the input pulley 59 when the lift motor MT3 rotates forward is defined as the first direction R1, and the rotation direction of the input pulley 59 when the lift motor MT3 rotates reverse is defined as the second direction R2.

The one-way clutch OW1 is built into the input pulley 59 and connects the input pulley 59 to the rotating shaft SF1. Therefore, the one-way clutch OW1 has the function of transmitting the rotation of the input pulley 59 in one direction to the drive gear Z1. Specifically, the one-way clutch OW1 transmits the second direction R2 of the input pulley 59 to the rotating shaft SF1 and the drive gear Z1 when the lift motor MT3 rotates in the reverse direction. On the other hand, the one-way clutch OW1 does not transmit the rotation of the input pulley 59 in the first direction R1 to the rotating shaft SF1 and the drive gear Z1 when the lift motor MT3 rotates forward.

The coupling member 60 is disposed on the rotation shaft SF1 and is capable of sliding in the axial direction of the rotation shaft SF1. In other words, the input pulley 59, the coupling member 60 and the drive gear Z1 are provided on a common rotation shaft SF1. The coupling member 60 has the function of connecting and disconnecting the drive transmission from the input pulley 59 to the drive gear Z1 when the lift motor MT3 rotates forward in conjunction with the installation and withdrawal of the storage cabinet 30. The detailed structure and function of the coupling member 60 will be described later.

The winding gear Z6 is attached to the winding shaft 56 and is connected to the drive gear Z1 via gears Z4 and Z5. Therefore, in conjunction with the rotation of the drive gear Z1, the winding shaft 56 rotates to wind or unwind the wires 55a to 55d, thereby lifting and lowering the stacking tray 32a.

The storage cabinet 30 has a frame 30a that constitutes the frame of the storage cabinet 30, and an auxiliary frame 30b that is fixed to the frame 30a with fasteners such as screws. The components of the lift motor MT3 and the drive transmission mechanism 38 are provided in the storage cabinet 30 by being supported by one or both of the frame 30a and the auxiliary frame 30b.

[Cutting off of driving transmission by coupling member]
Next, the configuration of the coupling mechanism 39 consisting of the input pulley 59 and the coupling member 60 will be described. Figures 6(a) and 6(b) are perspective views showing the state of the input pulley 59 and the coupling member 60 of the coupling mechanism 39. Figure 6(a) is a state diagram showing the state in which the coupling member 60 has moved to the connected position relative to the input pulley 59, and Figure 6(b) is a state diagram showing the state in which the coupling member 60 has moved to the disconnected position relative to the input pulley 59. Figures 7(a) and 7(b) are cross-sectional views explaining the configuration of the input pulley 59 and the coupling member 60. Figure 7(a) is a combined cross-sectional view combining a cross-section of the input pulley 59 cut at the concave engagement portion 64 and a cross-section of the coupling member 60 cut at the axial center position of the rotation shaft SF1, and Figure 7(b) is a perspective cross-sectional view of the input pulley 59 and the coupling member 60 cut at the axial center position of the rotation shaft SF1. Note that the biasing spring SP is not shown in Figures 7(a) and 7(b) for convenience.

As shown in Figures 6(a) and 6(b), the coupling member 60 is slidable in the axial direction relative to the rotation shaft SF1. Therefore, the coupling member 60 moves in the axial direction between a connected position where it engages with the input pulley 59 and a disconnected position where it is separated from the input pulley 59.

As shown in Figures 6(a) and 6(b), the coupling member 60 is provided with multiple convex engagement claws 65 that engage (mate) with the input pulley 59, and is also provided with an insertion hole 60b through which the rotating shaft SF1 passes. The input pulley 59 is provided with multiple concave engagement portions 64 that engage (mate) with the engagement claws 65 when the coupling member 60 moves to the connected position.

As shown in Figures 6(a)(b) and 7(a)(b), the convex portion of the engagement claw 65 of the coupling member 60 is formed with a side surface 65a extending toward the input pulley 59 and a spirally inclined inclined surface 65b, and the concave portion of the engagement portion 64 of the input pulley 59 is formed with a linear inner side surface 64a extending toward the coupling member 60 and a spirally inclined inclined surface 65b, forming a ratchet mechanism. In other words, as shown in Figures 6(a)(b) and 7(a)(b), the engagement claw 65 is shaped like a sawtooth gear in a ratchet mechanism.

[Input pulley and coupling component configuration]
The input pulley 59 transmits rotation in the first direction R1 to the coupling member 60 by engaging the engagement portion 64 with the engagement claw 65 of the coupling member 60. Specifically, when the input pulley 59 rotates in the first direction R1 with the engagement portion 64 of the input pulley 59 and the engagement claw 65 of the coupling member 60 engaged with each other, an inner side surface 64a on the opposite side to the rotation direction of the engagement portion 64 abuts against a side surface 65a of the engagement claw 65 in the rotation direction, thereby rotating the coupling member 60. The coupling member 60 transmits the rotation of the input pulley 59 in the first direction R1 to the rotation shaft SF1, and the coupling member 60 and the rotation shaft SF1 are configured to rotate integrally.

In this embodiment, in order to transmit the rotation of the coupling member 60 to the rotation shaft SF1 when the input pulley 59 rotates in the first direction R1, a pin 61 is provided on the rotation shaft SF1, and a slide hole 60c is formed integrally with the insertion hole 60b of the coupling member 60. The slide holes 36c are formed on both sides of the insertion hole 60b, and are formed so that the pin 61 can be inserted into the slide hole 60c.

Then, as shown in Figures 5(a) and (b), when the rotating shaft SF1 is inserted into the insertion hole 60b of the coupling member 60 and the pin 61 is inserted into the slide hole 60c, when the coupling member 60 rotates, the inner wall surface of the slide hole 60c abuts against the pin 61, and the coupling member 60 rotates the rotating shaft SF1 in the same direction.

The slide hole 60c is formed with a length corresponding to the movement amount of the coupling member 60 along the movement direction (axial direction) of the coupling member 60 as shown in Figures 7(a) and (b). The pin 61 is configured to slide in the slide hole 60c as the coupling 60 moves. The pin 61 also abuts against a restricting portion 60d provided at the end of the slide hole 60c on the input pulley 59 side as shown in Figure 7(a), restricting the movement of the coupling 60. In other words, when the storage 30 is pulled out, the coupling member 60 moves in the axial direction due to the biasing force of the biasing spring SP (not shown in Figure 7), and stops when the restricting portion 60d abuts against the pin 61 provided on the rotating shaft SF1, and this stopped position is the disconnection position where the input pulley 59 and the coupling member 60 are separated.

As shown in Fig. 6(b) and Fig. 7(b), the slide hole 60c is formed in a sector shape with the center of the insertion hole 60b as a fulcrum, and is formed so that the coupling member 60 can rotate a predetermined amount with respect to the stopped pin 61. Also, as shown in Fig. 7(a) and (b), the regulating portion 60d on the input pulley 59 side in the slide hole 60c has first and second cam portions 70 and 71 formed to protrude into the slide hole 60c and rotate the coupling member 60 a predetermined amount. The first and second cam portions 70 and 71 are formed on both sides of the rotation axis SF1 in the slide hole 60c. The first and second cam portions 70 and 71 have cam surfaces 70a and 71a inclined in the axial direction, respectively, and the cam surface 70a of the first cam portion 70 and the cam surface 71a of the second cam portion 71 are formed to face each other. The first cam portion 70 and the second cam portion 71 have the same shape and height, and both cam surfaces 70a, 71b have the same inclination angle.

When the coupling member 60 moves from the coupling position to the retracted position, the first and second cam surfaces 71a and 72b come into contact with the pin 61 and rotate a predetermined amount in the second direction R2.

The input pulley 59 rotates the coupling member 60 by abutting the inner surface 64a of its engagement portion 64 against the side surface 65a of the engagement claw 65, so when the lift motor MT3 is stopped, the inner surface 64a of the engagement portion 64 abuts against the side surface 65a of the engagement claw 65. If the coupling member 60 is separated from the input pulley 59 from a state in which the inner surface 64a of the engagement portion 64 abuts against the side surface 65a of the engagement claw 65, and then the coupling member 60 is connected to the input pulley 59, there is a risk that the apex of the side surface 65a of the engagement portion 64 on the coupling member 60 side and the apex of the engagement claw 65 will interfere with each other. However, according to the configuration of the coupling mechanism 39, when the coupling member 60 and the input pulley 59 are separated, the coupling member 60 moves due to the biasing force of the biasing spring SP, and the cam portions 70 and 71 come into contact with the pin 61, rotating the coupling member 60 a predetermined amount, so that it is possible to prevent interference between the top of the engagement claw 65 of the coupling member 60 and the top of the engagement portion 64 of the input pulley 59. Furthermore, since the engagement claw 65 has a helically inclined inclined surface 65b and the engagement portion 64 has a helically inclined inclined surface 65b, when the engagement claw 65 and the engagement portion 64 engage, the inclined surfaces 64b and 65b come into contact with each other while engaging, allowing for a smooth engagement operation.

With the above configuration, when the engagement claw 65 has moved to the disconnected position where it has disengaged from the input pulley 59, the coupling member 60 does not rotate even when the lift motor MT3 rotates forward. Furthermore, when the lift motor MT3 rotates forward, the input pulley 59 rotates in the first direction R1 in the direction in which the one-way clutch OW1 slips. Therefore, even if the lift motor MT3 rotates forward with the coupling member 60 in the disconnected position, the rotating shaft SF1 does not rotate and the winding shaft 56 does not drive.

On the other hand, when the lift motor MT3 rotates in the reverse direction while the coupling member 60 is in the disconnected position from the input pulley 59, the one-way clutch OW1 rotates the input pulley 59 and the rotating shaft SF1 in the second direction R2. As a result, the winding shaft 56 rotates in the direction in which the wires 55a to 55d are unwound, and the stacking tray 32a descends.

In contrast, when the coupling member 60 moves to the connection position where the engagement claw 65 engages with the input pulley 59 and the lifting motor MT3 rotates in the forward direction to rotate the input pulley 59, the abutting surface 64a of the engagement portion 64 of the input pulley 59 abuts against the abutting surface 65a of the engagement claw 65 of the coupling member 60, causing the coupling member 60 to rotate. When the coupling member 60 rotates together with the input pulley 59 in the first direction R1, the rotation shaft SF1 rotates via the pin 61. Then, as the rotation of the rotation shaft SF1 rotates the drive gear Z1 in the first direction R1, the winding shaft 56 is driven in the direction to wind up the wires 55a-55d, and the stacking tray 32a rises.

On the other hand, if the lift motor MT3 rotates in the reverse direction while the coupling member 60 is in the connected position where it engages with the input pulley 59, the one-way clutch OW1 rotates the input pulley 59 and the rotating shaft SF1 in the second direction R2. Therefore, just as when the coupling member 60 is disengaged from the input pulley 59, the winding shaft 56 drives in the direction that pays out the wires 55a to 55d, and the stacking tray 32a descends.

In this way, the drive transmission mechanism 38 of this embodiment is configured to transmit the driving force input from the lift motor MT3 through two branched paths. The first transmission path is a path that passes through the coupling member 60, and transmits the driving force (power) when the lift motor MT3 rotates forward. The second transmission path is a path that passes through the one-way clutch OW1, and transmits the driving force (power) when the lift motor MT3 rotates reverse. And, while the first transmission path switches between a connected state and a disconnected state depending on the position of the coupling member 60, the second transmission path is configured to be constantly connected regardless of the position of the coupling member 60.

[Opening and closing the storage unit and moving the coupling parts]
The coupling member 60 moves between the above-mentioned connected position ( FIG. 5( b )) and disconnected position ( FIG. 5( a )) in conjunction with the installation and withdrawal operations of the storage cabinet 30. The connected position is the position when the coupling member 60 connects the first transmission path, i.e., the position where the coupling member 60 transmits the drive from the input pulley 59 to the rotating shaft SF1, and the disconnected position is the position when the first transmission path is released from the connection and disconnected, i.e., the position where the coupling member 60 does not transmit the drive from the input pulley 59 to the rotating shaft SF1.

As shown in Figures 5(a) and (b), the biasing spring SP as a biasing means is disposed between the input pulley 59 and the coupling member 60. The biasing spring SP biases the coupling member 60 in a direction to move it away from the input pulley 59. In other words, the biasing spring SP biases the coupling member 60 in a direction to release the engagement between the engagement claw 65 of the coupling member 60 and the engagement portion 64 of the input pulley 59.

As shown in Figures 6(a) and 6(b), the housing 4a of the paper feeder main body 4 is provided with an abutment portion 62 that can abut against and slide on the coupling member 60. When the end face of the coupling member 60 on the side opposite the input pulley 59 abuts against the abutment portion 62 of the housing 4a, the coupling member 60 moves toward the input pulley 59 against the biasing force of the biasing spring SP.

With the above configuration, the coupling member 60 constituting the cutoff means of this embodiment moves between the connected position and the cutoff position in conjunction with the opening and closing of the storage 30, switching the first transmission path between the connected state and the cutoff state.

To be more specific, when the storage cabinet 30 is in the mounting position, i.e., when it is mounted on the housing 4a, the abutting portion 62 of the housing 4a abuts the coupling member 60, thereby holding the coupling member 60 in the coupled position (see FIG. 5(b)). As a result, the first transmission path of the drive transmission mechanism 38 is in a coupled state, and the forward and reverse rotation of the lift motor MT3 raises and lowers the stacking tray 32a. That is, when the storage cabinet is closed, the coupling mechanism 39 of this embodiment is in a coupled state in which it can transmit the first driving force from the drive source to the lift mechanism 37.

In contrast, when the storage cabinet 30 is in the withdrawn position, i.e., pulled out from the housing 204, the coupling member 60 moves away from the abutment portion 62 of the housing 4a, and the biasing force of the biasing spring SP moves the coupling member 60 to the disconnected position (see FIG. 5(a)). As a result, the first transmission path of the drive transmission mechanism 38 is disconnected, and the stacking tray 32a does not rise even if the lift motor MT3 rotates forward, and only the lowering of the stacking tray 32a is possible by the reverse rotation of the lift motor MT3. In other words, when the storage cabinet is open, the drive transmission mechanism of this embodiment is in a disconnected state in which the transmission of the first driving force from the drive source to the lift mechanism 37 is interrupted by the coupling mechanism 39.

Therefore, by configuring the coupling member 60 to move in conjunction with the installation and removal of the storage unit 30, it is possible to prevent the loading tray 32a from rising unexpectedly when the storage unit 30 is removed.

[Second embodiment]
In the above-described embodiment (first embodiment), the lift motor MT3 is provided in the storage case 30, and a coupling mechanism 39 is used in a paper feeder that can be attached to and pulled out of the paper feeder main body 4 together with the storage case 30, and the driving force (power) for forward rotation of the lift motor MT3 is transmitted or cut off depending on whether the storage case 30 is attached or pulled out. However, the present invention can also be adopted in a paper feeder in which the lift motor is provided in the paper feeder main body, and the driving force (power) is transmitted to the lift mechanism only when the storage case is attached to the paper feeder main body.

Specifically, as shown in FIG. 8, the housing 104a of the paper feeder main body 104 is provided with a lift motor MT103, a drive pulley 158 attached to the output shaft of the lift motor MT103, and an input pulley 159 to which the rotation of the drive pulley 158 is transmitted via a timing belt TB101. On the other hand, the storage 103 is provided with a coupling member 160 and a biasing spring SP101 attached to the rotating shaft SF101, a first transmission gear Z101 provided on the rotating shaft SF101, and a second transmission gear meshed with the first transmission gear Z101 and provided on the rotating shaft of the take-up pulley 153.

The coupling mechanism 139 and the rotating shaft SF101 are fitted with a pin 116 similar to the pin 61 of the first embodiment, and the input pulley 159 is provided with a convex engagement claw 165, an insertion hole through which the rotating shaft SF101 is inserted, a slide hole through which the pin 116 attached to the rotating shaft SF101 is inserted, and cam portions 170 and 171, similar to the coupling member 60 of the first embodiment. The input pulley 159 is also provided with a plurality of concave engagement portions that engage with the engagement claw 165 of the coupling member 160, similar to the input pulley 59 of the first embodiment. However, while the biasing spring SP1 of the first embodiment was provided between the input pulley 59 and the coupling member 60, the biasing spring SP101 in this embodiment is provided between the coupling member 160 and the first transmission gear Z101, and the cam portions 170 and 171 are formed on the first transmission gear Z10 side of the coupling member 160.

Figure 8(a) shows the state in which the storage case 130 is pulled out and the coupling member 160 is separated from the input pulley 159, in which the driving force of the lift motor MT103 is not transmitted to the lift mechanism. Figure 8(b) shows the state in which the storage case 130 is attached to the paper feeder main body 104 and the coupling member 160 is connected to the input pulley 159, in which the driving force of the lift motor MT103 is transmitted to the lift mechanism.

When the storage cabinet 130 is attached to the paper feeder main body 104 from the pulled-out state, the engagement claw 165 of the coupling member 160 engages with and is connected to the engagement portion 164 of the input pulley 59. At this time, the biasing spring SP101 is compressed, biasing the coupling member 160 toward the input pulley 159. This ensures that the coupling member 160 and the input pulley 159 are connected securely when the storage cabinet 130 is attached. Conversely, when the storage cabinet 130 is pulled out from the paper feeder main body 104, the coupling member 160 moves away from the input pulley and the engagement claw 165 and the engagement portion 164 are released. As a result, the driving force of the lifting motor MT103 is not transmitted to the lifting mechanism. At this time, the coupling member 160 moves along the rotation axis SF101 by the biasing spring SP101 in the direction in which the storage cabinet 130 is attached. During this movement, the pin 161 abuts against the cam portions 170, 171, rotating the coupling member 160 a predetermined amount. After rotating the coupling member 160, the pin 161 abuts against the restricting portion 160d, restricting the movement of the coupling member 160 in the mounting direction of the storage case 130.

The coupling mechanisms 60 and 160 are not limited to the above-described embodiments, but can be applied to anything that transmits the driving force of a driving source to a driven body.

1 Image forming device 4 Paper feed device 4a Housing (paper device main body)
30 Storage 32 Loading section 37 Lifting mechanism 38 Drive transmission mechanism 39 Coupling mechanism 59 Input pulley (first drive transmission member)
64 Engagement portion 60 Coupling member (second drive transmission member)
60b Insertion hole 60c Slide hole 60d Restriction portion 70 First cam portion 72 Second cam portion 61 Pin MT3 Lifting motor SP Spring (moving means)
SF1 Rotation axis OW Lifting motor

Claims (7)

In a coupling mechanism that transmits power from a driving source to a driven body,
A first transmission member;
a second transmission member that is connected to and separated from the first transmission member;
a shaft member supporting the second transmission member;
a moving means for moving the second transmission member along a shaft member when the first transmission member and the second transmission member are separated from each other;
a restricting member provided at a predetermined position of the shaft member and configured to restrict movement of the second transmission member by the moving means;
a rotating member provided on the second transmission member and abutting against the regulating member to rotate the second transmission member by a predetermined amount;
A coupling mechanism comprising: The coupling mechanism according to claim 1, in which a recess formed on one of the first and second transmission members engages with a protrusion formed on the other of the first and second transmission members to connect the first and second transmission members. The coupling mechanism according to claim 2, wherein the convex portion comprises an abutment surface that abuts against the side of the concave portion and an inclined surface that is inclined relative to the abutment surface. A sheet feeding device including a storage case that can be pulled out from a device body, a stacking tray that is provided in the storage case and that stacks sheets, a lifting mechanism that lifts the stacking tray, a forward/ reverse rotatable drive motor that drives the lifting mechanism, and a drive transmission means that transmits the power of the drive means to the lifting mechanism,
the drive transmission means has a coupling mechanism that transmits the power of the drive means to the lifting mechanism when the storage case is attached to the device body and does not transmit the power of the drive means to the lifting mechanism when the storage case is pulled out from the device body,
the coupling mechanism includes a first transmission member, a second transmission member that is coupled to the first transmission member when the storage case is attached to the device body and that moves away from the first transmission member when the storage case is pulled out from the device body, and a rotating means that rotates the second transmission member by a predetermined amount when the second transmission member and the first transmission member move away from each other ;
The coupling mechanism transmits the forward rotation of the drive motor to the lifting mechanism when the storage cabinet is attached to the device main body, and the lifting mechanism lifts the loading tray with the forward rotation of the drive motor transmitted from the coupling mechanism . 5. The paper feeder according to claim 4 , wherein the first and second transmission members are connected by engaging a recess formed on one of the first and second transmission members with a protrusion formed on the other. 6. The paper feeder according to claim 5 , wherein the convex portion comprises a contact surface that contacts a side portion of the concave portion and an inclined surface that is inclined relative to the contact surface. a shaft member supporting the second transmission member;
a moving means for moving the second transmission member along a shaft member when the first transmission member and the second transmission member are separated from each other,
the rotating means includes a restricting member provided at a predetermined position of the shaft member and restricting the movement of the second transmission member by the moving means;
7. The paper feeder according to claim 4 , further comprising: a rotating member provided on the second transmission member, the rotating member contacting the regulating member to rotate the second transmission member by a predetermined amount.

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