Media supply device and image forming apparatus

Abstract

To provide a medium supply device that, when an additional medium supply unit is not connected thereto, prevents a configuration to transmit a driving force from being exposed to the outside of the device, and when the additional medium supply unit is connected thereto, easily exposes the configuration to transmit the driving force for reliable connection.SOLUTION: A medium supply device comprises: a medium supply unit; an additional medium supply unit; a relay conveyance unit that receives a medium supplied from the additional medium supply unit; a driving force transmission unit that transmits a driving force to the relay conveyance unit; and a transmission switching unit that switches between a transmission state where the driving force transmission unit transmits the driving force to the relay conveyance unit and a cut-off state where the transmission of the driving force is cut off. The transmission switching unit includes a transmission switching member the position of which is variable depending on the presence or absence of the connection of the medium supply unit and the additional medium supply unit. When the additional medium supply unit is connected to the medium supply unit, the transmission switching member moves to a position for allowing transmission of the driving force, and when the additional medium supply unit is not connected to the medium supply unit, moves to a position for cutting off the driving force.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a medium supply device and an image forming apparatus.

Background Art

[0002] An image forming apparatus that forms an image on a sheet-like medium is known. The image forming apparatus includes a medium supply device for supplying the medium to an image forming unit. Some medium supply devices are configured to be able to connect a medium supply addition unit for increasing the storage capacity of the medium.

[0003] In a conventional image forming apparatus, a configuration is known in which a medium supply device is provided in the apparatus main body and a medium supply addition unit is externally connected. In the image forming apparatus, a configuration example in which a transport mechanism that supplies and transports the medium from the medium supply addition unit is also arranged in the transport path inside the apparatus main body is also known. Further, in an image forming apparatus, there are needs such as making the target range of the image forming process smaller than before and increasing the storage capacity of the medium.

[0004] For example, when the medium supply addition unit is connected, the dimensions of the entire apparatus become larger, and the distance between the transport mechanism arranged inside the apparatus main body and the transport mechanism on the medium supply addition unit side becomes longer. Therefore, the distance between the transport rollers for transporting the medium becomes longer. On the other hand, in order to cope with the transport of small-sized media, it is necessary to shorten the distance between the transport rollers.

[0005] In order to cope with small-sized media, a relay roller is provided at a position that relays the transport from a transport path (bank transport path) for supplying the medium from the medium supply addition device to a transport path (main body transport path) inside the main body of the image forming apparatus. It is conceivable that this relay roller is provided inside the main body of the image forming apparatus. In the following description, the relay roller is referred to as a "main body-bank relay roller".

[0006] The main unit-bank relay roller is positioned on a different transport path from the transport path of media supplied from the media supply device of the image forming apparatus or other media supply means provided by the image forming apparatus (e.g., manual feeding). This makes it possible to transport smaller media than before, but it requires a new drive source for the main unit-bank relay roller.

[0007] If the drive source for the main unit-bank relay roller is the same as the drive source for the main unit relay roller, the increase in the number of drive sources and the increase in manufacturing costs can be suppressed. However, since the main unit-bank relay roller will be driven even when the media supply extension is not connected, unnecessary driving of the conveyor roller will occur. In this case, problems such as a deterioration in noise levels and the need for increased torque of the drive source compared to when only the main unit relay roller is driven will arise.

[0008] As a configuration to reduce noise from the main unit-bank relay roller, a configuration is disclosed in which the drive source on the media supply expansion unit side drives the transport roller of the image forming apparatus (see, for example, Patent Document 1). [Overview of the project] [Problems that the invention aims to solve]

[0009] As shown in the configuration of Patent Document 1, if the drive source for the main body-bank relay roller is provided in the media supply extension unit, a configuration is required to connect the main body of the image forming apparatus and the media supply extension unit and transmit the driving force for supplying media from the media supply extension unit to the image forming apparatus. This configuration has the problem that the gears, which are connected when the media supply extension unit is connected to the image forming apparatus, may collide with each other and be damaged during connection, leading to malfunction.

[0010] Furthermore, the gear on the image forming apparatus side that engages with the media supply expansion unit must be exposed to the outside of the apparatus. This means that when not connected, the internal structure remains exposed to the outside, which can lead to malfunctions.

[0011] Furthermore, even if the media supply expansion unit is not connected, the image forming apparatus must be equipped with a drive force transmission mechanism that transmits driving force to the transport rollers that operate for transporting the media, such as unused roller pairs or gears. This presents challenges such as increased manufacturing costs, larger size of the apparatus, and increased weight.

[0012] The present invention aims to provide a media supply device that prevents the drive force transmission component from being exposed to the outside of the device when the media supply expansion unit is not connected, and that allows for easy exposure and reliable connection of the drive force transmission component when the media supply expansion unit is connected. [Means for solving the problem]

[0013] To solve the above technical problems, one aspect of the present invention relates to a media supply device, comprising: a media supply main unit for separating and supplying sheet-like media contained in a storage space; a media supply extension unit for separating and supplying sheet-like media contained in an additional storage space and equipped with a connection positioning member for positioning when connected to the media supply main unit; a relay transport unit provided in the media supply main unit to receive media supplied from the media supply extension unit; a drive force transmission unit having a first drive force transmission member provided in the media supply main unit for transmitting drive force to the relay transport unit; and a transmission switching unit that switches between a transmission state in which the drive force transmission unit transmits the drive force to the relay transport unit and a disconnection state in which the transmission of the drive force is blocked. The medium supply main body and the medium supply extension are provided with a transmission switching member whose position is variable depending on whether or not the medium supply main body and the medium supply extension are connected, the housing of the medium supply main body is provided with an opening into which the first drive force transmission member is exposed, the transmission switching member has a pressing surface that is pressed by the connection positioning member and has a slope configured to fit into an oval positioning shape, is biased by a biasing means to move to a position that covers the opening and blocks the drive force when the medium supply extension is not connected to the medium supply main body, and when the medium supply extension is connected to the medium supply main body the slope is pressed by the connection positioning member ,beforeIt is characterized by moving to a position where the driving force can be transmitted. [Effects of the Invention]

[0014] According to the present invention, when the media supply expansion unit is not connected, the configuration for transmitting the driving force is prevented from being exposed to the outside of the device, and when the media supply expansion unit is connected, the configuration for transmitting the driving force can be easily exposed and reliably connected. [Brief explanation of the drawing]

[0015] [Figure 1] A schematic diagram of an embodiment of the image forming apparatus according to the present invention. [Figure 2] A diagram showing an example of the transport configuration of a conventional main unit. [Figure 3] A diagram showing an example of the drive configuration of a conventional main unit. [Figure 4] This figure shows an example of the drive configuration provided in the main unit according to this embodiment. [Figure 5] This figure shows an example of the drive configuration of the media supply unit according to this embodiment. [Figure 6] This schematic diagram illustrates the state of the media supply device according to this embodiment before the connection between the media supply main unit and the media supply extension unit. [Figure 7] A perspective view of the connection positioning member between the media supply main unit and the media supply extension unit according to this embodiment. [Figure 8] This figure shows an overview of the operation of the shielding member provided in the media supply main unit according to this embodiment. [Figure 9] This figure shows an overview of the operation of the shielding member and the connection of the drive configuration according to this embodiment. [Figure 10] A perspective view showing an overview of the operation of the shielding member and the connection of the drive configuration according to this embodiment. [Figure 11] A perspective view showing an overview of the operation of the shielding member and the connection of the drive configuration according to this embodiment. [Figure 12] A perspective view showing an overview of the operation of the shielding member and the connection of the drive configuration according to this embodiment. [Figure 13]A diagram showing another example of the drive mechanism of the media supply main body according to this embodiment. [Figure 14] A perspective view showing a detailed example of the drive mechanism of the media supply main body according to this embodiment. [Figure 15] A diagram showing another example of the drive configuration provided in the main body unit of the image forming apparatus according to the present invention.

Embodiments for Carrying Out the Invention

[0016] Hereinafter, embodiments of a media supply device and an image forming apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a multifunction peripheral (MFP) 1 as an embodiment of the image forming apparatus according to the present invention.

[0017] [Embodiment of Image Forming Apparatus] The MFP 1 shown in FIG. 1 is generally a device that combines a copier, a printer, a facsimile, and these functions. For example, the MFP 1 includes a main body unit 10 and a media supply unit 100. The media supply unit 100 includes a media supply main body portion 110 and a media supply additional portion 120, and corresponds to the media supply device according to the present invention.

[0018] The media supply main body portion 110 includes a main body paper feed cassette 111 as a storage space for storing sheets of paper P as media on which an image is formed. The main body paper feed cassette 111 mainly stores standard-sized paper P. Further, the media supply main body portion 110 includes a manual feed tray 141 for handling media having dimensions that cannot be accommodated in the main body paper feed cassette 111 or for image formation (printing) on a small number of sheets of paper P. The manual feed tray 141 is provided for supplying paper P manually and is attached to the media supply main body portion 110 so as to be openable and closable.

[0019] Paper P, separated one sheet at a time from the main paper cassette 111 or manual feed tray 141 by the main paper feed roller pair 112 or manual feed roller pair 142, is fed toward the registration roller 115 provided on the main unit 10. When the leading edge of the paper P abuts against the registration roller 115, the registration roller 115 stops rotating. This aligns the position of the leading edge (the front end in the transport direction) of the paper P.

[0020] After the leading edge position of the paper P is aligned, the registration roller 115 feeds the paper P toward the transfer roller 132, which constitutes the image forming section of the main unit 10. The timing at which the registration roller 115 feeds the paper P is when the toner image and the paper position coincide.

[0021] Then, the paper P onto which the unfixed toner image has been transferred by the transfer roller 132 is sent to the fuser unit 131, which is part of the image forming section of the main unit 10. After the unfixed toner image is fixed to the paper P in the fuser unit 131, it is discharged to the output tray 134 by the output / reversal roller 133 of the main unit 10. When fixing an image to both sides of the paper P (forming an image), the transport path of the paper P with the image formed on the first side is first switched by the branching claw 135 to transport it to the double-sided path. The paper P that has returned to the upstream side of the registration roller 115 by the double-sided path is aligned by the registration roller 115, and then the image is fixed to the second side before being discharged to the output tray 134.

[0022] As described above, the media supply unit 110 can form a predetermined image on the paper P and discharge it using the registration roller 115 and other components that constitute the media transport unit.

[0023] In order to transport the paper P to the fixing unit 131 at a predetermined timing, the leading edge of the paper P must be aligned with the registration roller 115. Therefore, the distance between the registration roller 115 and the pair of transport rollers positioned upstream of the registration roller 115 in the transport direction must be such that it can accommodate the minimum size of the paper P on which the image is formed.

[0024] In other words, in order to accommodate smaller paper sizes P, it is necessary to shorten the distance between pairs of transport rollers that make up the transport path leading to the registration roller 115 (distance between transport rollers).

[0025] Therefore, as shown in Figure 1, a main transport roller 113 is provided downstream of the main paper feed roller pair 112 and the manual feed roller pair 142, and upstream of the registration roller 115, as an intermediate transport roller pair for transporting the paper P to the registration roller 115.

[0026] Furthermore, in order to enable the transport of small-sized paper P from the manual feed tray 141, it is preferable to provide a manual feed relay transport roller 143 upstream of the main transport roller 113 and downstream of the manual feed paper feed roller pair 142.

[0027] Furthermore, as illustrated in Figure 1, the media supply expansion unit 120 includes an additional paper feed cassette 121 as an additional storage space to increase the storage capacity of paper P, which is the medium on which images are formed. The media supply expansion unit 120 is attached to the MFP1 by being connected to the media supply main unit 110. The MFP1 with the media supply expansion unit 120 attached can form images not only on the paper P supplied from the media supply main unit 110 but also on the paper P supplied from the media supply expansion unit 120. In other words, the main unit 10 of the MFP1 can be supplied with paper P from the additional paper feed cassette 121, just as it can be supplied with paper P from the main paper feed cassette 111.

[0028] The sheets of paper P, separated one by one from the additional paper feed cassette 121 by the bank paper feed roller pair 122, are fed towards the registration roller 115 via the bank transport roller 123 and the main transport roller 113. The subsequent operation is the same as described above.

[0029] [First Embodiment of a Media Supply Device] Next, a first embodiment of the media supply device according to the present invention will be described in detail with reference to the drawings. Figure 2 shows a conventional example of the arrangement of roller mechanisms that constitute a transport path for transporting paper P to the main unit 10 in the media supply unit 100. Figure 2 shows a conventional example of the arrangement of roller mechanisms when the media supply extension unit 120 is connected to the media supply main unit 110.

[0030] As shown in Figure 2, when paper P is supplied from the additional paper feed cassette 121, it is transported to the media supply main unit 110 via the bank transport roller 123. The transport path is then configured so that the paper P transported from the media supply extension unit 120 can be received by the main unit-bank relay roller 114. The transport path is shown by a dashed line.

[0031] The paper P received by the main unit-bank relay roller 114 is then transported to the main unit transport roller 113 and the registration roller 115, which are located further downstream. In other words, the main unit-bank relay roller 114 is one of a pair of transport rollers that only needs to operate when paper P is supplied from the media supply extension unit 120.

[0032] As shown in Figure 2, the distance b between the bank transport roller 123 and the main unit-bank relay roller 114, and the distance a between the main unit-bank relay roller 114 and the main unit transport roller 113 are set to match the smallest size of paper P that the MFP1 can handle. That is, they are set to be shorter than the length (paper length) in the transport direction of the smallest size of paper P. This makes it possible to transport the paper P supplied from the media supply extension unit 120 to the main unit transport roller 113.

[0033] If we assume that the minimum size of the transportable paper P is A6, then the distance between rollers (roller pitch) should be set shorter than the paper length of 148 mm. Specifically, taking into account fluctuations in the assembly precision of the transport configuration formed in the media supply main unit 110, variations in the actual size of the paper P, and variations in the transport posture of the paper P, the distance between rollers should be set to 138 mm or less.

[0034] Figure 3 shows a conventional example of the arrangement of drive sources for driving each roller in the conveyor roller arrangement shown in Figure 2. As shown in Figure 3, the drive force from the main body-side drive source 19, which is provided in the media supply main body 110, is transmitted to the main body-bank relay roller 114. In this conventional example, the drive force is transmitted from the main body-side drive source 19 to the drive gear 16 of the main body-bank relay roller 114 via multiple gears. For example, the drive gear 15 of the main body conveyor roller 113, which is connected to the rotating shaft of the main body-side drive source 19 and rotated, and the drive force is transmitted to the drive gear 16 via multiple idler gears 17 (17a, 17b, 17c) which are connected to the drive gear 15 and rotated.

[0035] The main unit's drive source 19 is composed of a motor or a drive mechanism such as an electromagnetic clutch driven by a motor. Detailed illustrations of the motor, electromagnetic clutch, and other drive mechanisms are omitted in the following description.

[0036] The arrangement and drive configuration of the drive source shown in Figure 3 is configured to drive the main unit-bank relay roller 114 even when paper is not being fed from the media supply extension unit 120. In other words, since the transport rollers and gears that do not contribute to the transport of paper P are also rotated, it becomes necessary to increase the noise level due to increased operating noise and to increase the torque of the main unit-side drive source 19.

[0037] Figure 4 shows an example in which a drive source for the main body-bank relay roller 114 is provided in the media supply extension unit 120, which is an embodiment of the media supply device according to the present invention, in the arrangement of the transport rollers illustrated in Figure 2. As shown in Figure 4, a bank transport motor 29 is arranged in the media supply extension unit 120 as a bank-side drive source, and the bank transport motor 29 is configured to function as a drive source for the bank transport roller 123. The bank transport motor 29 may also be equipped with an electromagnetic clutch via motor drive, and the driving force is transmitted from the motor's drive shaft to the bank transport roller 123 via the electromagnetic clutch.

[0038] As illustrated in Figure 4, the drive gear 25 of the bank transport roller 123, which is driven by the bank transport motor 29, is connected to the bank-side body-to-bank transmission gear 28 via an idler gear 27, thereby transmitting the driving force. A portion of the bank-side body-to-bank transmission gear 28 is exposed to the outside of the device (outside the housing of the media supply extension unit 120) from the upper surface of the media supply extension unit 120.

[0039] The drive gear 16 of the main body-bank relay roller 114 is driven and connected to the main body-bank transmission gear 18 on the main body side, and a portion of the main body-bank transmission gear 18 on the main body side is exposed to the outside of the device (outside the housing of the medium supply main body 110) from the lower surface of the medium supply main body 110.

[0040] Therefore, when the media supply extension unit 120 is connected to (attached to) the media supply main unit 110, the exposed portion of the main unit-bank transmission gear 18 on the main unit side and the exposed portion of the main unit-bank transmission gear 28 on the bank side engage with each other. This allows the main unit-bank relay roller 114 to be driven by the driving force of the bank transport motor 29 provided in the media supply extension unit 120. In other words, the main unit-bank relay roller 114 is driven using the driving force of the bank transport motor 29 only when paper P is supplied from the media supply extension unit 120.

[0041] Furthermore, it is desirable that the bank-side main body-bank transmission gear 28 be configured to prevent tooth root contact or insufficient meshing when connected to the main body-bank transmission gear 18.

[0042] Figure 5 is a perspective view of the drive configuration including the bank-side body-to-bank transmission gear 28 provided in the media supply expansion unit 120. As already explained, the bank-side body-to-bank transmission gear 28 needs to be connected to the body-side body-to-bank transmission gear 18 when connecting the media supply expansion unit 120 to the media supply body unit 110. Therefore, it is preferable that the bank-side body-to-bank transmission gear 28 is configured to swing in the connection direction when connected.

[0043] As shown in Figure 5, the bank-side body-to-bank transmission gear 28 is held by the gear holding member 32. The idler gear 27 is also held by the gear holding member 32. The gear holding member 32 is biased in one direction by a spring 33, with the central axis of the idler gear 27 as the pivot point. The bank-side body-to-bank transmission gear 28 is provided at the end (other end) opposite to the end (one end) where the spring 33 is provided.

[0044] The spring 33 is a tension spring and is provided to pull one end of the gear holding member 32. The biasing force of this spring 33 biases the bank-side body-bank transmission gear 28 in an arc direction around the rotation axis of the idler gear 27. This biasing direction is the direction that pushes the media supply extension 120 outward (upward), and is the connection direction when it is connected to the body-side body-bank transmission gear 18.

[0045] With this configuration, when the media supply extension unit 120 is attached to the media supply main unit 110, the elastic force of the spring 33 absorbs the impact when the bank-side main unit-bank transmission gear 28 comes into contact with the main unit-bank transmission gear 18. As a result, the bank-side main unit-bank transmission gear 28 swings downward moderately for a moment. Then, due to the biasing force of the spring 33, the bank-side main unit-bank transmission gear 28 is pressed against the main unit-bank transmission gear 18, ensuring the appropriate gear meshing position.

[0046] The rotating shaft of the bank transport motor 29 is connected to the drive gear 25. The drive gear 25 is located on the rotating shaft of the bank transport roller 123, so the bank transport roller 123 rotates when the bank transport motor 29 is driven. The drive gear 25 is connected to the idler gear 27, so when the bank transport motor 29 is driven, the idler gear 27 rotates simultaneously with the bank transport roller 123. The idler gear 27 is connected to the bank-side body-to-bank transmission gear 28, so when the bank transport motor 29 is driven, the bank-side body-to-bank transmission gear 28 rotates.

[0047] As described above, when the bank-side body-to-bank transmission gear 28 rotates due to the rotation of the bank transport motor 29, the biasing force of the spring 33 presses the bank-side body-to-bank transmission gear 28 against the body-side body-to-bank transmission gear 18. As a result, the driving force from the bank transport motor 29 is transmitted to the body-side body-to-bank transmission gear 18 via the bank-side body-to-bank transmission gear 28. It is preferable to arrange the gear train so that when a driving force is applied, the bank-side body-to-bank transmission gear 28 bites into the body-side body-to-bank transmission gear 18 due to the load of the driving force.

[0048] Furthermore, the more gears that are connected, the more sliding points there are, and the greater the loss in the transmission of driving force. Therefore, in order to reduce noise and torque when attaching the media supply extension unit 120 to the media supply main unit 110, it is better to configure the gear train with as few components as possible. Also, if the transport speed of the paper P is set slower than that of the main unit-bank relay roller 114, the paper P will become a taut load. Therefore, it is better to set the speed faster by adjusting the gear reduction ratio and roller system.

[0049] As described above, in the drive configuration according to the embodiment of the present invention (illustrated in Figures 4 and 5), the main unit-bank relay roller 114 provided on the media supply main unit 110 can only be driven when paper is being fed from the media supply extension unit 120. When the media supply extension unit 120 is not attached to the media supply main unit 110 (when paper is not being fed from the media supply extension unit 120), for example, when feeding from the main unit tray or manual feed, it is not necessary to drive the main unit-bank relay roller 114 or the multiple gears. Therefore, the operating noise can be reduced, and there is no need to unnecessarily increase the torque of the main unit-side drive source 19.

[0050] As explained earlier, when the drive mechanism illustrated in Figures 4 and 5 is adopted, a portion of the lower surface of the main body-bank transmission gear 18 on the main body side is exposed to the outside of the medium supply main body 110, which raises several issues that need to be addressed.

[0051] For example, in order to expose the gears (drive gears housed inside the device), which are part of the drive mechanism, it is necessary to provide an opening in part of the exterior of the media supply main unit 110. It is conceivable that foreign matter may enter the inside of the media supply main unit 110 or the main unit 10 through this opening. It is also conceivable that if the inside of the media supply main unit 110 or the main unit 10 heats up, high heat may leak out to the outside. Furthermore, the drive gears used in the media supply main unit 110 and the media supply extension unit 120 are often made of resin, and in particular, polyacetal resin (POM) gears are often used to ensure sliding properties. Generally, POM is a material that does not easily have high flame retardancy. It is desirable to avoid exposing the main unit-bank transmission gear 18 made of this material to the outside of the device.

[0052] Furthermore, when attaching the media supply extension unit 120 to the media supply main unit 110, the main unit 10 is typically lifted and the media supply main unit 110 is placed on top of the media supply extension unit 120. At this time, it is necessary to visually check the gears in order to ensure that the main unit-bank transmission gear 18 and the bank-side main unit-bank transmission gear 28 make proper contact. However, it is difficult to visually check the relative positions of the gears when placing the media supply main unit 110 on top of the media supply extension unit 120. Therefore, there is a concern that poor contact or damage to the gears may occur when attaching the media supply extension unit 120 to the media supply main unit 110.

[0053] Furthermore, the drive gear 16 of the main body-bank relay roller 114 and the main body-bank transmission gear 18 on the main body side are unnecessary parts when the media supply extension unit 120 is not installed on the main body unit 10 (media supply main body section 110). Therefore, it is necessary to keep parts that become completely unnecessary depending on the usage, which can lead to increased manufacturing costs and increased equipment weight.

[0054] This embodiment resolves the concerns described above and solves the problems of the present invention, preventing the exposure of the connection configuration when the media supply extension unit 120 is not connected to the media supply main unit 110, and allowing for easy connection when they are connected.

[0055] [First Embodiment of a Media Supply Device] Figure 6 is a schematic diagram illustrating the state of the media supply main unit 110 and the media supply extension unit 120 before connection, as an embodiment of the media supply device.

[0056] As shown in Figure 6, the upper surface of the casing of the media supply extension unit 120 is provided with positioning pins 30 to facilitate the relative positioning of the connecting gears when connecting it to the media supply main unit 110. The positioning pins 30 allow the media supply main unit 110 to be easily and properly engaged with the media supply extension unit 120 without visually checking the relative positions of the engaging gears when performing the connection work. This makes it easy and reliable to connect the transport path when the media supply extension unit 120 is connected to the media supply main unit 110.

[0057] The positioning pin 30 is a connection positioning member that facilitates determining the relative positional relationship when connecting the media supply extension unit 120 to the media supply main unit 110. More specifically, the positioning pin 30 determines the relative positions of the main unit-bank transmission gear 18 and the bank-side main unit-bank transmission gear 28, allowing them to be connected.

[0058] The main body-bank transmission gear 18 on the main body side corresponds to a part of the first drive force transmission member provided in the media supply main body section 110. The bank-side main body-bank transmission gear 28 corresponds to a part of the second drive force transmission member provided in the media supply extension section 120.

[0059] Figure 7 is an enlarged perspective view of the installation area of ​​the positioning pin 30. As shown in Figure 7, the positioning pin 30 is a tapered cylindrical member that is erected on the upper surface of the media supply extension unit 120 with a predetermined length L. The length L of the positioning pin 30 is set to be longer than the sum of the exposed length of the bank-side body-bank transmission gear 28 and the exposed length of the body-side body-bank transmission gear 18.

[0060] As a result, when attaching the media supply extension unit 120 to the media supply main unit 110, inserting the positioning pin 30 into the main frame 42 (described later) provided on the media supply main unit 110 side appropriately determines the relative positional relationship that enables normal drive connection. As a result, it is possible to avoid contact between the contacting gears (bank-side main unit-bank transmission gear 28 and main unit-side main unit-bank transmission gear 18) in a direction that would cause damage, and it is possible to prevent damage to the gears when connecting the media supply main unit 110 and the media supply extension unit 120.

[0061] Furthermore, as shown in Figure 7, an earth member 31 is placed near the positioning pin 30. This makes it easy to connect the earth to the main unit 10 and the medium supply extension unit 120, similar to the positioning.

[0062] Next, the transmission switching unit that switches between the transmission state and the blocked state according to this embodiment, and the shielding plate 41 as a transmission switching member, will be described. The transmission state refers to the state in which the drive force transmission unit (body-side body-bank transmission gear 18 and bank-side body-bank transmission gear 28) that transmits drive force from the media supply extension unit 120 to the relay transport unit (body-bank relay roller 114) provided in the media supply main unit 110 transmits drive force. The blocked state refers to the state in which the transmission of drive force from the media supply extension unit 120 to the drive force transmission unit (body-side body-bank transmission gear 18 and bank-side body-bank transmission gear 28) that transmits drive force to the relay transport unit (body-bank relay roller 114) provided in the media supply main unit 110 is blocked.

[0063] Figure 8 shows an example in which the shielding plate 41 is provided on the bottom side of the media supply main unit 110. As shown in Figure 8(a), the shielding plate 41 is provided below the position where the main unit-bank transmission gear 18 is located. When the media supply extension unit 120 is not connected, the shielding plate 41 is configured to remain in a position that prevents the main unit-bank transmission gear 18 from being exposed.

[0064] Then, as shown in Figure 8(b), the shielding plate 41 moves when the media supply extension unit 120 is connected. Specifically, it moves from a position where the exposure of the main body-bank transmission gear 18 on the main body side is prevented (shielded state) to a position where the main body-bank transmission gear 18 on the main body side can be exposed to the media supply extension unit 120 (transmission state). For example, the shielding plate 41 moves in the direction of the white arrow M shown in Figure 8(b).

[0065] Next, using positioning pins 30, an example of the relative positioning when the media supply extension unit 120 is connected to the media supply main unit 110, and the operation of moving the shielding plate 41 to expose the main unit-bank transmission gear 18 on the main unit side will be explained with reference to several drawings.

[0066] Figure 9 is a cross-sectional view showing the operation of the positioning pin 30 and the shielding plate 41. Figure 10 is a perspective view of the operation of the positioning pin 30 and the shielding plate 41 from the media supply extension unit 120 side. Figure 11 is a perspective view of the operation of the positioning pin 30 and the shielding plate 41 from the media supply main unit 110 side, with the main frame 42 omitted. Figure 12 is a perspective view of the operation of the positioning pin 30 and the shielding plate 41 as seen from the media supply main unit 110.

[0067] As shown in Figure 9, the main frame 42 on the bottom side of the media supply main unit 110 (the side to which the media supply extension unit 120 is connected) is provided with a main frame hole 42a for exposing the main body-bank transmission gear 18 on the main body side. The main frame 42 is also provided with a main frame positioning hole 42b into which the positioning pin 30 on the media supply extension unit 120 side is inserted. The main frame positioning hole 42b acts as a secondary reference for positioning when connecting the media supply extension unit 120 to the media supply main unit 110. Therefore, the shape of the main frame positioning hole 42b is oval.

[0068] The shielding plate 41 is held movably with respect to the main frame 42. The retaining members for the shielding plate 41 are not shown in the illustration. The shielding plate 41 is held with respect to the main frame 42 so as to cover the main frame hole 42a and the main frame positioning hole 42b.

[0069] Furthermore, the shielding plate 41 is biased by a biasing mechanism in the direction of the black-colored arrow S shown in Figure 9. Note that the biasing mechanism is not shown in the illustration.

[0070] The shielding plate 41 is a plate-shaped member that moves along the main frame 42, and has a flat surface that is aligned with the bottom surface of the main frame 42 and an inclined surface that partially fits into the main frame positioning hole 42b.

[0071] Figures 9(a), 10(a), 11(a), and 12(a) illustrate the state of the shielding plate 41 when the media supply extension unit 120 is not connected to the media supply main unit 110. The shielding plate 41 is provided with gear exposure holes 41a. When the media supply extension unit 120 is not connected, the gear exposure holes 41a of the shielding plate 41 are in a position that does not expose the main unit-bank transmission gear 18 on the main unit side (shielded state).

[0072] Figures 9(b), 10(b), 11(b), and 12(b) illustrate the state of the shielding plate 41 when the media supply extension unit 120 is connected to the media supply main unit 110. When connecting the media supply extension unit 120 to the media supply main unit 110, the positioning pins 30 provided on the media supply extension unit 120 are inserted into the positioning holes 42b of the main frame. At this time, the relative positions of the positioning pins 30 and the shielding plate 41 are adjusted in advance so that the positioning pins 30 press against the inclined surface of the shielding plate 41. As a result, the position where the positioning pins 30 press against the inclined surface of the shielding plate 41 moves along the inclined surface, causing the shielding plate 41 to move in a direction perpendicular to the direction of pressure applied by the positioning pins 30.

[0073] As described above, when the media supply extension unit 120 is connected to the media supply main unit 110, the shielding plate 41 moves in the direction of the white arrow M in Figure 9(b), etc. When the media supply extension unit 120 is connected to the media supply main unit 110, the gear exposure hole 41a provided in the shielding plate 41 is positioned below the main unit-bank transmission gear 18 (transmission state). As a result, the main unit-bank transmission gear 18 is exposed to the outside of the machine and drives and connects with the bank-side main unit-bank transmission gear 28 provided in the media supply extension unit 120. Then, the driving force from the bank transport motor 29 provided in the media supply extension unit 120 is transmitted to the main unit-bank relay roller 114.

[0074] With the above configuration, when only the media supply main unit 110 is used to supply paper P to the main unit 10, the main unit-bank transmission gear 18 on the main unit side is shielded by the shielding plate 41 and can be prevented from being exposed. In other words, damage to the gear can be prevented when it is not in use. In addition, when the media supply extension unit 120 is not used, the transport mechanism on the main unit 10 side is not exposed to the outside of the device during operation, which further enhances the operational safety of the main unit 10.

[0075] [Second Embodiment of a Media Supply Device] Next, another embodiment of the media supply device according to the present invention will be described with reference to Figure 13. As shown in Figure 13, the drive force transmission section, which includes the main body-bank relay roller 114, drive gear 16, and main body-bank transmission gear 18 according to this embodiment, is provided as a detachable attachment 50 to the media supply unit 100.

[0076] Figure 13(a) illustrates the state in which the attachment 50 is attached to the media supply main unit 110. Figure 13(b) illustrates the state in which the attachment 50 is attached to and removed from the media supply main unit 110. Figure 13(c) illustrates the state in which the media supply extension unit 120 is connected with the attachment 50 attached to the media supply main unit 110.

[0077] Figure 14 illustrates a perspective view of attachment 50. As shown in Figure 14, attachment 50 holds the main body-bank relay rollers 114 (114a, 114b), the drive gear 16, and the main body-bank transmission gear 18 on the main body side. It also consists of a frame that holds the drive gear 16 and a shape that guides the paper being transported P.

[0078] The attachment 50 is detachable from the MFP1. Therefore, even with the attachment 50 detached, the MFP1 can be used normally if only the media supply unit 110 is used.

[0079] When connecting the media supply extension unit 120 to the MFP1, the attachment 50 is mounted on the media supply main unit 110. As a result, the paper P fed from the media supply extension unit 120 is transported to the registration roller 115 via the main unit-bank relay roller 114 provided on the attachment 50.

[0080] As described above, by configuring the drive transmission section with attachment 50, manufacturing costs can be reduced without installing unnecessary conveying rollers or the like.

[0081] [Third Embodiment of a Media Supply Device] Next, yet another embodiment of the media supply device according to the present invention will be described with reference to Figure 15. As shown in Figure 15, the media supply unit 100 according to this embodiment has a plurality of media supply extension units 120 connected in a stacked configuration.

[0082] The media supply expansion unit 120 according to this embodiment comprises a first media supply expansion unit 120a and a second media supply expansion unit 120b, the second media supply expansion unit 120b is connected to the first media supply expansion unit 120a, and the first media supply expansion unit 120a is connected to the media supply main unit 110.

[0083] By arranging a relay roller, its drive gear, and connecting gear similar to those used for the media supply main unit 110 below the first media supply extension unit 120a, the drive can also be connected to the lower second media supply extension unit 120b. This configuration allows multiple media supply extension units 120 to be used as a media supply unit 100.

[0084] Note that while Figure 15 illustrates a two-tiered configuration of the media supply expansion unit 120, it is not limited to this configuration. The media supply expansion unit 120 may be stacked in a three-tiered configuration or more.

[0085] It should be noted that the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the technical essence, and all technical matters included in the technical concept described in the claims are subject to the present invention. The above embodiments are shown as preferred examples, but those skilled in the art can realize various modifications from the disclosed content. Such modifications are also included in the technical scope described in the claims. [Explanation of Symbols]

[0086] 1: MFP 10: Main Unit 15: Drive gear 16: Drive gear 17: Idler Gear 18: Bank transmission gear 19: Main unit drive source 25: Drive gear 27: Idler Gear 28: Bank transmission gear 29: Bank transport motor 30: Positioning pin 31: Grounding component 32: Gear retaining member 33: Spring 41: Shielding plate 41a: Gear exposed hole 42: Main frame 42a: Hole in the main frame 42b: Main frame positioning holes 50: Attachment 100: Media supply unit 110: Media supply main unit 111: Main paper feed cassette 112: Main unit paper feed roller pair 113: Main unit transport roller 114: Bank relay roller 115: Registroller 120: Media supply expansion unit 121: Additional paper feed cassette 122: Bank feed roller pair 123: Bank conveyor roller 131: Fixing section 132: Transfer Roller 133: Reversible Roller 134: Paper output tray 135: Branching claw 141: Manual feed tray 142: Manual feed roller pair 143: Manual feed relay conveyor roller [Prior art documents] [Patent Documents]

[0087] [Patent Document 1] Japanese Patent Publication No. 2012-180142

Claims

1. A media supply unit that separates and supplies sheet-like media contained in a containment space, A media supply expansion unit is provided which separates and supplies sheet-like media contained in an additional storage space and which is equipped with a connection positioning member for positioning when connecting to the media supply main unit, A relay transport unit is provided in the media supply main unit and receives media supplied from the media supply expansion unit, A drive force transmission unit having a first drive force transmission member provided in the media supply main body and transmitting drive force to the relay transport unit, The drive force transmission unit includes a transmission switching unit that switches between a transmission state in which the drive force is transmitted to the relay transport unit and a blocking state in which the transmission of the drive force is interrupted. Equipped with, The transmission switching unit includes a transmission switching member whose position is variable depending on whether or not the media supply main unit and the media supply extension unit are connected. The housing of the media supply main body is provided with an opening through which the first drive force transmission member is exposed. The transmission switching member has a pressing surface that is pressed by the connecting positioning member, and has a slanted surface configured to fit into an oval positioning shape. When the media supply extension unit is not connected to the media supply main unit, it is biased by a biasing means to move to a position that covers the opening and blocks the driving force. When the media supply extension unit is connected to the media supply main unit, the inclined surface is pressed by the connection positioning member and moves to a position where the driving force can be transmitted. A media supply device characterized by the following features.

2. The medium supply device according to claim 1, wherein the transmission switching member is a plate-shaped member that is movable along the surface of the housing on which the opening is provided.

3. The aforementioned drive force transmission unit is The media supply expansion unit includes a second drive force transmission member, The media supply device according to claim 1 or 2, wherein when the transmission switching member moves to a position that enables the transmission of the driving force, a part of the first driving force transmission member is exposed outside the housing of the media supply main body and comes into contact with a part of the second driving force transmission member, and the driving force of the drive source provided in the media supply extension is transmitted from the second driving force transmission member to the first driving force transmission member.

4. The media supply device according to claim 3, wherein the connection positioning member determines the relative position of the media supply main body and the media supply extension when connected.

5. The medium supply device according to claim 4, wherein the connection positioning member moves the transmission switching member to a position that enables the transmission of the driving force.

6. The media supply device according to claim 4 or 5, wherein the connecting positioning member is a member that is longer than the sum of the exposed height of a part of the first drive force transmission member and the exposed height of a part of the second drive force transmission member that is exposed toward the media supply main body.

7. There are multiple media supply expansion units. A media supply extension unit is connected to the lower part of the media supply main unit. A media supply device according to any one of claims 1 to 6, wherein another media supply expansion unit is connected to the lower part of the said one media supply expansion unit.

8. The media supply device according to claim 7, wherein the first media supply extension unit transmits the driving force from the drive source provided by the other media supply extension unit to the media supply main unit.

9. The medium supply device according to any one of claims 1 to 8, wherein the drive force transmission unit is detachable.

10. An image forming unit that forms an image on a sheet-like medium, The image forming unit includes a medium transport unit for transporting the medium, An image forming apparatus comprising a media supply device according to any one of claims 1 to 9, which includes a media supply main body for supplying the aforementioned medium.

Images