JP2020033111A - Carrier device and medium processing apparatus using the same - Google Patents

Abstract

To move carrier members, constituted in a pair to hold and carry a medium, axially with a low load in a vibration-suppressed state even if the medium is loaded in a twisting direction.SOLUTION: A carrier device comprises: carrier means 1 which includes paired axially movable carrier members 1a, 1b capable of holding and carrying a medium 10, drive transmission means 2 which is provided at an axial end part of one carrying member 1a between the pair-constituted carrying members 1a, 1b and drives the carrying member 1. The drive transmission means 2 includes: shaft joint means 4 which includes an inner joint element 5 fixed to the axial end part of the one carrier member 1a and an outer joint element 6 holding the inner joint element 5 axially movably, and couples the one carrier member 1a axially movably; and helical gear transmission means 7 which has a multiple-helical gear train 8 for transmitting rotational driving force from a drive source 3, and transmits the rotational driving force from the drive source 3 to the outer joint element 6 of the shaft joint means 4 through the helical gear train 8.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a transport device that transports a medium and a medium processing device using the transport device.

Conventionally, as this type of transport device, for example, those described in Patent Documents 1 and 2 are already known.
Patent Document 1 discloses that, when a paper aligning device is configured by a registration roller device arranged on a linear portion of a photosensitive drum and a pre-registration roller device arranged on an upstream portion thereof, a driving roller member of the pre-registration roller device includes: The drive shaft is provided so as to be movable in the axial direction, the regulating member is arranged on the shaft, and further, when the reaction force of the torsional stress of the paper is applied to the drive roller member, the drive shaft is moved. An image forming apparatus has been disclosed in which a sheet is normally sent out, and thereafter, in a state where the stress of the sheet has been eliminated, a driving shaft can be returned to an original position by a leaf spring member of a regulating member. I have.
Japanese Patent Application Laid-Open No. H11-146,086 discloses a method of detecting a position shift amount of a recording medium in a diagonal direction while transporting the recording medium while nipping the recording medium by nipping rollers by a plurality of driving motors (driving means) fixedly installed on a frame of the transporting apparatus. There is disclosed an image forming apparatus which corrects a position shift amount in a width direction of a recording medium while correcting the position.

JP-A-8-225196 (Example, FIG. 2) Japanese Patent Application Laid-Open No. 2014-193770 (Embodiment for carrying out the invention, FIG. 4)

Patent Documents 1 and 2 disclose an aspect in which drive transmission is performed by a spur gear train as drive transmission means for a pair of conveying members, but the spur gear train has a low meshing ratio and causes noise and vibration. There is a concern that it is easy to become. Further, in a mode in which the drive is transmitted only by the helical gear train instead of the spur gear train, there is a concern that the movement in the axial direction becomes too high.
The technical problem to be solved by the present invention is that even if a load is applied to the medium in the twisting direction, a pair of transport members that sandwich and transport the medium can be pivoted at a low load with vibration suppressed. To allow movement in the direction.

  The invention according to claim 1 is a transporting means including a paired transporting member capable of nipping and transporting the medium and moving in the axial direction, and an axial end of one transporting member of the paired transporting member. And a drive transmitting means for driving the conveying member, wherein the driving transmitting means moves the inner joint element fixed to an axial end of the one conveying member and the inner joint element in the axial direction. Including an outer joint element for holding as possible, a shaft coupling means for movably connecting the one transfer member in the axial direction, and a plurality of helical gear trains for transmitting rotational driving force from a driving source, A helical gear transmitting means for transmitting the rotational driving force from the drive source to the outer joint element of the shaft coupling means via the helical gear train.

The invention according to claim 2 is the transfer device according to claim 1, wherein the shaft coupling means has a play allowance in which eccentricity due to displacement of the center position of the outer joint element and the inner joint element is allowable, A transport device having a gap corresponding to the play allowance between the outer joint element and a joint holding portion that holds the outer joint element.
According to a third aspect of the present invention, in the transfer device according to the second aspect, a play allowance of the shaft coupling means is larger than a shift amount obtained by calculating a tolerance of a center position of the outer joint element and the inner joint element. A transfer device characterized in that the shaft joint action is set in a range in which the shaft joint action is possible.
According to a fourth aspect of the present invention, in the transfer device according to the first aspect, the shaft coupling means is configured such that the outer joint element and the inner joint element are relatively movable in an axial direction and relatively movable in a rotational direction. A transfer device characterized by being disabled.
According to a fifth aspect of the present invention, in the transfer device according to the fourth aspect, the shaft coupling means is constituted by a spur gear in which the outer joint element and the inner joint element mesh with each other so as to be relatively movable in the axial direction. It is a transfer device characterized by the above.
According to a sixth aspect of the present invention, in the transfer device according to the fifth aspect, the allowance of the shaft coupling means is set such that the engagement amount of the spur gear falls within a range smaller than the module of the spur gear. It is a transfer device characterized by the above.
According to a seventh aspect of the present invention, in the transfer device according to the first aspect, the helical gear transmitting means is such that a helical gear center located at a last stage of the helical gear train is concentric with an outer joint element of the shaft coupling means. It is a transfer device characterized by the above.
The invention according to claim 8 is the conveying device according to claim 1 or 7, wherein the helical gear transmission means is configured such that a helical gear located at the last stage of the helical gear train has an outer peripheral portion of an outer joint element of the shaft coupling means. The transfer device is provided integrally with the transfer device.
According to a ninth aspect of the present invention, in the transfer device according to the first aspect, the shaft coupling means has the play allowance in a direction crossing a driving force direction received by the outer coupling element from the helical gear transmission means. It is a transfer device characterized by the above.
According to a tenth aspect of the present invention, in the transfer device according to the ninth aspect, the shaft coupling means forms a gap corresponding to the play allowance between the outer joint element and a joint holding portion that holds the outer joint element. Wherein the clearance has a dimension perpendicular to the driving force direction larger than the dimension in the driving force direction received by the outer joint element from the helical gear transmission means.
According to an eleventh aspect of the present invention, in the transfer device according to the first aspect, the shaft coupling means has a stopper means between the outer joint element and the inner joint element for regulating an axial position of the outer joint element and the inner joint element. Transport device.

  According to a twelfth aspect of the present invention, there is provided a medium aligning device that transports a medium after aligning the medium, and is provided upstream of the medium aligning device in a transport direction of the medium, and the medium is aligned when the medium is aligned by the medium aligning device. A transport device according to any one of claims 1 to 11, which is transported movably in a thrust direction.

According to the first aspect of the present invention, even if a load in the twisting direction occurs on the medium, the paired conveying members that sandwich and convey the medium can be moved in the axial direction at a low load with the vibration suppressed. Can be moved.
According to the second aspect of the invention, the axial sliding resistance between the outer joint element and the inner joint element of the shaft coupling means can be reduced.
According to the invention according to claim 3, it is possible to easily set a play allowance of the shaft coupling means necessary for reducing the axial sliding resistance between both elements of the shaft coupling means.
According to the invention according to claim 4, the shaft coupling means can be easily embodied from the functions necessary for both elements of the shaft coupling means.
According to the invention according to claim 5, functions required for both elements of the shaft coupling means can be easily realized.
According to the invention of claim 6, in a mode in which spur gears are used for both elements of the shaft coupling means, the function of the shaft coupling means can be reliably realized.
According to the invention according to claim 7, the drive transmission between the helical gear transmission means and the shaft coupling means can be efficiently realized.
According to the invention according to claim 8, the drive transmission between the helical gear transmission means and the shaft coupling means can be efficiently realized with a small number of parts.
According to the ninth aspect of the invention, the centering action between the two elements of the shaft coupling means can be easily realized.
According to the tenth aspect, it is effective in exhibiting the centering action between both elements of the shaft coupling means.
According to the eleventh aspect of the invention, the movement of the paired conveying member in the axial direction can be easily restricted by partially using the shaft coupling means.
According to the twelfth aspect of the present invention, when the medium is aligned by the medium alignment device, even if a load is applied to the medium in the twisting direction, the pair of conveying members that sandwich and convey the medium vibrate. It is possible to construct a medium processing device including a transport device that enables movement in the axial direction with a low load in a suppressed state.

(A) is an explanatory view showing an outline of an embodiment of a medium processing apparatus to which the present invention is applied, (b) is an arrow view showing a transport device viewed from the direction B in (a), and (c) is ( It is explanatory drawing which shows an example of the drive transmission means in b). FIG. 1 is an explanatory diagram illustrating an overall configuration of an image forming apparatus as a medium processing apparatus according to Embodiment 1. (A) is an explanatory view showing the behavior of sheet conveyance by a position alignment roll used in the first embodiment and a conveyance roll (conveying device) positioned upstream of the sheet conveyance direction, and (b) is a direction B in (a). FIG. 3 is a view as viewed from an arrow, showing the transport device as viewed from above. FIG. 4 is an explanatory diagram showing details of a shaft coupling part of an IV part in FIG. 3. FIG. 4 is an explanatory diagram illustrating a main part of a drive transmission mechanism including a shaft coupling part of an IV part in FIG. 3. FIG. 6 is an explanatory perspective view showing details of a drive transmission mechanism shown in FIG. 5. FIG. 7 is a perspective explanatory view showing a state where a part of a support housing is removed from a drive transmission mechanism in FIG. 6. FIG. 8 is a perspective explanatory view showing a state in which a helical gear transmission mechanism and an outer coupling of a shaft coupling component are further removed from the drive transmission mechanism in FIG. 7. (A) is an explanatory view of the direction of action of the driving force by the drive transmission mechanism, and (b) is an explanatory view showing a play allowance between the inner coupling and the outer coupling which are both elements of the shaft coupling part. (A) is an explanatory view showing an example of a stopper mechanism on one end side of the drive roll of the transport device according to Embodiment 1, and (b) is an explanatory view showing an example of a stopper mechanism on the other end side of the drive roll. . FIG. 9 is an explanatory diagram illustrating a main part of a drive transmission mechanism used in the transport device according to the second embodiment.

Outline of Embodiment FIG. 1A shows an outline of an embodiment of a medium processing apparatus to which the present invention is applied.
In the figure, a medium processing device is provided at a position upstream of the medium alignment device 11 in the transport direction of the medium 10, and a medium alignment device 11 that transports the medium 10 after aligning the medium 10. And a transport device 12 for transporting the medium 10 movably in the thrust direction.
In this example, the transport device 12 is provided on the upstream side of the medium alignment device 11 in the transport direction of the medium 10. When the medium 10 is aligned by the medium alignment device 11, It is intended to effectively prevent a situation in which wrinkles occur in the medium 10 held by the transport device 12 even when the load described above occurs.
Here, the medium processing apparatus including the transport device 12 is not limited to an image forming apparatus that forms an image on the medium 10 but also includes a medium cutting apparatus that cuts the medium 10.
In FIG. 1A, the transport device 12 is installed on the upstream side in the transport direction of the medium 10 with respect to the medium aligning device 11, but is not limited to this, and is not limited to this. Needless to say, it may be installed at an arbitrary location.

  In this example, as shown in FIGS. 1B and 1C, the transport device 12 includes a pair of transport members 1a and 1b that can sandwich and transport the medium 10 and move in the axial direction. And a drive transmission means 2 provided at an axial end of one of the paired transport members 1a and 1b to drive the transport member 1a. Including an inner joint element 5 fixed to an axial end of the member 1a and an outer joint element 6 for holding the inner joint element 5 movably in the axial direction, one of the transport members 1a is movable in the axial direction. And a plurality of helical gear trains 8 for transmitting the rotational driving force from the drive source 3 to the outer joint element 6 of the shaft coupling means 4 via the helical gear train 8. Helical gear transmission means 7 for transmitting the rotational driving force from It is intended to.

In such a technical means, the transporting means 1 may be appropriately selected as long as it includes a pair of transporting members 1a and 1b which sandwich and transport the medium 10.
Further, the shaft coupling means 4 may include the outer coupling element 6 and the inner coupling element 5 and may be appropriately selected as long as it is movable in the axial direction.
Further, the helical gear transmission means 7 only needs to have a plurality of helical gear trains 8, and does not include those having a spur gear train in the middle.
In this case, a function (thrust-free) is realized in which the helical gear transmission means 7 keeps good transmission of the driving force and the shaft coupling means 4 allows the conveyance members 1a and 1b to move in the axial direction. Things.

Next, a typical mode or a preferable mode of the transport device 12 used in the present embodiment will be described.
First, as a typical mode of the shaft coupling means 4, as shown in FIG. 1C, there is a play allowance α in which eccentricity due to displacement of the center position of the outer joint element 6 and the inner joint element 5 is allowable. And a mode in which a gap g corresponding to the play allowance α is provided between the outer joint element 6 and the joint holding portion 9 that holds the outer joint element 6. In this example, since the eccentricity adjustment operation of the shaft coupling means 4 can be performed by the gap g of the joint holding section 9, a sliding portion (corresponding to a sliding movement section) between the elements of the shaft coupling means 4 is provided. ) Changes from static friction to dynamic friction.
In this example, as a preferred method of setting the play allowance α of the shaft coupling means 4, the deviation amount is larger than the deviation calculated by the tolerance calculation of the center positions of the outer joint element 6 and the inner joint element 5, and the shaft joint action can be performed between both elements Set in a suitable range.

  Another typical embodiment of the shaft coupling means 4 is a mode in which the outer joint element 6 and the inner joint element 5 are relatively movable with respect to the axial direction and are not relatively movable with respect to the rotational direction. Can be As an example of the present example, there is one configured by a spur gear in which an outer joint element and an inner joint element mesh with each other so as to be relatively movable in the axial direction. In this case, the play allowance α of the shaft coupling means 4 may be set so that the meshing amount of the spur gear falls within a range smaller than that of the spur gear module.

Further, as a typical embodiment of the helical gear transmission means 7, there is an embodiment in which the center of the helical gear located at the last stage of the helical gear train 8 is concentric with the outer joint element 6 of the shaft coupling means 4.
Here, as a preferred embodiment of the helical gear transmission means 7, there is an aspect in which a helical gear located at the last stage of the helical gear train 8 is integrally provided on the outer peripheral portion of the outer joint element 6 of the shaft coupling means 4. Can be In this example, since the helical gear train 8 can be arranged on the outer peripheral portion of the outer joint element 6 of the shaft coupling means 4, the shaft coupling means 4 and the helical gear train 8 are arranged along the axial direction of the transport member 1a. It is possible to reduce the size of the drive transmission means 2 in the direction along the axial direction of the transport member 1a, as compared with the aspect in which the drive transmission means 2 are arranged side by side.

In addition, as a preferable embodiment of the shaft coupling means 4, there is a mode in which the play allowance α is provided in a direction intersecting with the driving force direction received by the outer joint element 6 from the helical gear transmission means 7. For example, in a mode in which the play allowance is ensured only in the driving force direction that the outer joint element 6 receives from the helical gear transmission means 7, the centering action between the two elements 5, 6 of the shaft coupling means 4 is affected by the driving force. However, if the play allowance α is secured in the direction intersecting the driving force direction, the centering action between the two elements 5 and 6 of the shaft coupling means 4 is easily secured.
In this embodiment, as a particularly effective mode, the shaft coupling means 4 has a gap g corresponding to the play allowance α between the outer joint element 6 and the joint holding portion 9 that holds the outer joint element 6, It is preferable that the gap g has a dimension perpendicular to the driving force direction larger than the dimension in the driving force direction received by the outer joint element 6 from the helical gear transmission means 7.
Furthermore, from the viewpoint of restricting the amount of axial movement of the paired conveying members 1a and 1b, a mode is provided between the outer joint element 6 and the inner joint element 5 that has the stopper means 15 for restricting the axial position of both. Is preferred.

Hereinafter, the present invention will be described in more detail based on embodiments shown in the accompanying drawings.
◎ Embodiment 1
FIG. 2 shows an overall configuration of an image forming apparatus as a medium processing apparatus according to the first embodiment.
-Overall configuration of image forming apparatus-
In FIG. 1, an image forming apparatus 20 is configured as, for example, a full-color image forming apparatus employing an electrophotographic method. In this example, glass or the like is provided on an upper part of an apparatus housing 21 in which an image forming unit 25 is built. A platen 22 made of a transparent material is provided, and an automatic document feeder 23 that automatically feeds a document (not shown) to a predetermined reading position on the platen 22, and a document or platen conveyed by the automatic document feeder 23. This embodiment includes an image reading device 24 that reads a document placed on a document 22. Note that the image forming apparatus 20 may of course include a mode in which the automatic document feeder 23 and the image reading device 24 are not provided.

-Imaging unit-
In the present embodiment, the image forming unit 25 in the apparatus housing 21 employs an intermediate transfer method, and includes, for example, a plurality of color components (yellow (Y), magenta, (M), cyan (C), black (K)) image forming units 30 (specifically, 30a to 30d) capable of forming images, and the image formed by each image forming unit 30 is recorded on a recording medium. Before the image is transferred to the sheet S, the image is temporarily transferred and held on, for example, a belt-shaped intermediate transfer body 40.
In this example, the image forming section 30 (30a to 30d) has a photoconductor 31 as an image holding member, and around the photoconductor 31, a charging device 32 for charging the photoconductor 31, and a charged photoconductor 31 are provided. An exposure device 33 such as an LED writing device for writing an electrostatic latent image on the body 31 and an electrostatic latent image formed on the photoconductor 31 can be formed by a developer containing at least toner as charged image forming particles. A developing device 34 for visualizing an image, a primary transfer device 35 provided on the back side of the intermediate transfer body 40 facing the photoconductor 31 and transferring the developed image formed on the photoconductor 31 to the intermediate transfer body 40 side; And a cleaning device 36 for cleaning residual toner and the like remaining on the photoreceptor 31.

The intermediate transfer body 40 is formed of, for example, a belt-shaped member. In this example, the intermediate transfer body 40 is disposed above each of the image forming units 30 (30a to 30d), and is wound around a plurality of stretching rolls 41 to 44 and circulates and rotates. It has become. And in this example, the stretching roll 41 is used as a driving roll, and the stretching rolls 42 to 44 are used as driven rolls. Of the driven rolls, the tension roll 42 is configured to also serve as one element of a secondary transfer device 50 as a transfer unit described later, and the tension roll 43 applies tension to the intermediate transfer body 40. The tension roll 44 is used as a facing roll that forms the image forming surface of the intermediate transfer body 40 with respect to the photoconductor 31. An intermediate transfer member cleaning device 45 for cleaning residual toner and the like on the intermediate transfer member 40 is provided at a portion of the intermediate transfer member 40 that faces the tension roll 41, for example.
Further, in the present embodiment, a plurality of developer cartridges 38 (specifically, developer containers each containing a developer (image forming material) containing at least each color component toner) are provided above the intermediate transfer body 40. Specifically, 38a to 38d) are installed side by side in a substantially horizontal direction. Under each developer cartridge 38, a developer transporting device 39 connected to the developing device 34 of each image forming unit 30 is provided, and the developer is transported to the corresponding developing device 34 via each developer transporting device 39. The medicine is replenished.

-Secondary transfer device-
In the present embodiment, a secondary transfer device 50 is provided as a transfer unit for transferring an image formed by the toner on the intermediate transfer body 40 onto the sheet S. In the secondary transfer device 50, the transfer roll 51 is disposed in contact with a portion of the intermediate transfer body 40 corresponding to the stretch roll 42, and the stretch roll 42 facing the transfer roll 51 functions as an electrode roll. A transfer voltage is applied between the intermediate transfer body 40 and the paper S to apply a transfer electric field required for image transfer between the intermediate transfer body 40 and the paper S.

-Fixing device-
In the present embodiment, a fixing device 60 as a fixing unit is installed substantially directly above the secondary transfer device 50.
In this example, the fixing device 60 includes a heat fixing roll 61 that fixes an image formed of unfixed toner on the sheet S by heating the sheet S, and an endless belt-shaped pressure fixing belt 62 that presses the sheet S against the heat fixing roll 61. The sheet S is nipped and conveyed to a contact area between the heat fixing roll 61 and the pressure fixing belt 62 to heat and pressure-fix an unfixed toner image on the sheet S. Note that the fixing device 60 is not necessarily limited to the heating and pressure fixing method, and may be appropriately selected from a non-contact heating method, a laser beam fixing method, a pressure fixing method, and the like.

-Paper transport system-
In the present embodiment, the paper transport system 80 has a plurality of paper supply devices 81 and 82 below the apparatus housing 21, and is sent from the feed units 81 a and 82 a of one of the paper supply devices 81 and 82. The sheet S is transported upward from below by a transport roller 84 appropriately installed along a vertical transport path 83 extending substantially in the vertical direction, and after being aligned by a position alignment roll 85 in front of the secondary transfer device 50, the secondary After passing through the transfer device 50, it passes through the fixing device 60, and the first sheet storage portion 91 provided on the upper portion of the device housing 21 or the second sheet storage portion provided on the side of the device housing 21. The curl-corrected sheet S is transported to the unit 92.
In this example, in addition to the vertical transport path 83, the paper transport system 80 includes a return transport path 93 provided to bypass the vertical transport path 83, And a horizontal transport path 95 extending substantially horizontally in a space above the developer cartridge 38.

Here, a first paper storage unit 91 is provided at the end position of the vertical transport path 83, and a discharge roll 86 that can be rotated forward and backward is provided immediately before the first paper storage unit 91. A switching gate 87 for switching the route is provided at a branch position between the vertical transport route 83 and the horizontal transport route 95, and a switching gate for switching the route is provided at the intersection of the vertical transport route 83 and the return transport route 93. A gate 88 is provided. The switching gate 88 reverses the discharge roll 86 while maintaining the state in which the single-sided image-formed paper S is nipped by the discharge roll 86 via the vertical transfer path 83, and returns to the return transfer path 93. A first switching operation for pulling in the sheet S and a second switching operation for pulling the sheet S on which single-sided image formation has been performed via the vertical transport path 83 to the return transport path 93 without change are performed.
Further, a plurality of transport rolls 94 are provided in the return transport path 93, a plurality of transport rolls 96 are provided in the horizontal transport path 95, and a second sheet storage portion 92 is provided at the end position of the horizontal transport path 95. Are provided, and a discharge roll 97 is provided immediately before the second paper storage unit 92.

Therefore, in the present embodiment, in the double-sided image forming mode, the sheet S on which single-sided image formation has been performed via the vertical transport path 83 is reversed again via the return transport path 93 to a position before the position alignment roll 85 of the vertical transport path 83. Then, the sheet S is transported along the vertical transport path 83 so that an image is formed on the other side of the sheet S. When it is desired to store the paper S in the second paper storage unit 92, the paper S on which single-sided or double-sided image formation has been performed may be switched to the horizontal transport path 95 in the middle of the vertical transport path 83 and transported. Good.
In the present embodiment, a manual paper feeder 98 that can supply manual paper toward the vertical transport path 83 is provided on the opposite side of the second paper storage unit 92 of the apparatus housing 21. The sheet S sent from the feed unit 98a of the sheet feeder 98 is carried into the vertical transport path 83, and is then transported along the vertical transport path 83 through the transport roll 84 and the position alignment roll 85.

-Functions required for paper transport device-
In the present embodiment, as shown in FIG. 3A, the position adjusting roll 85 strikes the sheet S as a skew correction of the sheet S, forms a loop, aligns the leading end of the sheet S, and then adjusts the sheet S. Is being transported.
However, when the sheet S is twisted in the loop portion Sa and the sheet S is transported as it is, there is a possibility that a problem such as generation of wrinkles may occur.
Therefore, in the present embodiment, of the plurality of transport rolls 84 installed in the vertical transport path 83, the transport roll located at least on the upstream side in the paper transport direction of the position alignment roll 85 and closest to the position alignment roll 85 84f (84) is required to have a so-called thrust-free function that can move in the axial direction.

-Configuration example of the transport roll 84f-
For this reason, in this example, as the transport device 100 that transports the sheet, the transport roll 84f has a pair of rolls that can pinch and transport the sheet S and move in the axial direction, and one of the pair of rolls. The roll is used as the drive roll 101, the other roll is used as the driven roll 102, and a drive transmission mechanism 120 for transmitting a drive force from a drive motor (not shown) is provided at an axial end of the drive roll 101. A configuration is employed.
In this example, when the leading end of the paper S abuts against the position alignment roll 85, the driving roll 101 and the driven roll 102 of the transport roll 84f are moved in the axial direction by the stress in the twist direction generated in the loop portion Sa of the paper S. Thereby, the twist accompanying the positional alignment of the sheet S is eliminated.

In this example, as shown in FIG. 3B, the drive roll 101 has a support shaft 103 extending in the width direction intersecting with the transport direction of the sheet S, and both ends of the support shaft 103 are bearings 104 and 105. In the vicinity of the center of the support shaft 103, a plurality of roll members 106 made of, for example, rubber or resin are provided around the center position of the support shaft 103. Then two) are fitted and fixed.
On the other hand, as shown in FIG. 3B, the driven roll 102 has a support shaft 107 extending in the width direction intersecting the transport direction of the sheet S, and the roll member of the drive roll 101 in the vicinity of the center of the support shaft 107. A plurality of pinch roll members 108 are fitted and fixed in a position facing the roll member 106 so as to contact the roll member 106.

In the present example, the driven roll 102 can rotate a part of an intermediate region between the pinch roll member 108 and both ends of the support shaft 107 of the support shaft 107 by bearings 109 and 110 and along the axial direction. The bearings 109 and 110 are pressed by a pressing spring 111 such that the bearings 109 and 110 are movably held and the roll member 106 of the drive roll 101 and the pinch roll member 108 of the driven roll 102 are pressed against each other with a predetermined pressure. I have.
Further, near the both ends of the support shaft 107 of the driven roll 102, a return spring 112 that compresses or pulls when the driven roll 102 moves in the axial direction from the initial position is provided, and the paper S is moved by the transport roll 84f. When passing, the driven roll 102 returns to the initial position by using the urging force of the return spring 112.
Furthermore, in this example, the drive roll 101 and the driven roll 102 are connected in a state where the one end side of the support shaft 103 and the support shaft 107 is allowed to rotate by the link arm 113, so that both the shafts 103 and 107 can move in the axial direction. Movement is linked.
The bearings 104 and 105 of the drive roll 101 and the bearings 109 and 110 of the driven roll 102 are supported by a support frame 115.

-Drive transmission mechanism-
In the present embodiment, as shown in FIGS. 3 to 5, the drive transmission mechanism 120 includes a coupling 121 as a shaft coupling means for connecting the drive roll 101 of the transport roll 84f so as to be movable in the axial direction. A helical gear transmission mechanism 150 for transmitting the rotational driving force from the drive motor 160 to the coupling 121 is provided.
<Coupling>
In this example, the coupling 121 is formed by a connected portion 103a (a large-diameter portion for retaining in this example and a small-diameter shaft portion protruding from the large-diameter portion) formed at one end of the support shaft 103 of the drive roll 101. ), And an outer coupling 123 provided so as to cover the periphery of the inner coupling 122 and holding the inner coupling 122 so as to be movable in the axial direction.
In this example, the inner coupling 122 is formed with a coupling hole 125 that fits into the coupled portion 103a of the drive roll 101 in the substantially cylindrical coupling body 131, and is coupled and fixed to the coupled portion 103a. It has become so. 4 and 8, reference numeral 126 denotes a stop ring which is attached to the tip of the connected portion 103a and tightens and fixes the inner coupling 122.

Further, the outer coupling 123 has a coupling body 131 rotatably held by the coupling holding frame 130. In this example, the coupling main body 131 has a cylindrical portion 132 in which at least the outer peripheral portion of the coupling main body 131 of the inner coupling 122 fits with a play. Are also provided with small-diameter cylindrical shaft portions 133, 134. Here, holding holes 135 and 136 for rotatably holding the cylindrical shaft portions 133 and 134 of the coupling main body 131 are formed in the coupling holding frame 130.
In this example, the outer peripheral surface of the inner coupling 122 and the inner peripheral surface of the outer coupling 123 are constituted by spur gears 127 and 137 that mesh with each other so as to be relatively movable in the axial direction of the drive roll 101.

-Helical gear transmission mechanism-
In this embodiment, as shown in FIGS. 5 to 7, the helical gear transmission mechanism 150 includes a plurality of (three in this example) helical gear trains 151 (the helical gears) for transmitting the rotational driving force from the drive motor 160. 151a to 151c), and the rotational driving force from the drive motor 160 is transmitted to the outer coupling 123 of the coupling 121 via the helical gear train 151.
In particular, in this example, the helical gear transmission mechanism 150 is provided such that the center of the helical gear 151 c located at the last stage of the helical gear train 151 is concentric with the outer coupling 123 of the coupling 121. Specifically, a helical gear 151 c located at the last stage of the helical gear train 151 is integrally provided on the outer peripheral surface of the outer coupling 123 of the coupling 121.
In this example, as shown in FIGS. 6 to 8, the coupling holding frame 130 is positioned and fixed on a positioning stud 138 provided at a predetermined position on the support frame 115 of the transport device 100. The coupling holding frame 130 also holds the support shafts of the helical gears 151a and 151b excluding the last stage of the helical gear train 151.

<Setting the coupling allowance>
In the present embodiment, as shown in FIG. 4, the coupling 121 has a play allowance α that allows eccentricity due to a shift in the center position of the outer coupling 123 and the inner coupling 122. A gap g corresponding to the play allowance α is provided between the cylindrical shaft portions 133 and 134 and the holding holes 135 and 136 of the coupling holding frame 130.
Here, the play allowance α is larger than the amount of deviation of the center position of the outer coupling 123 and the inner coupling 122 by the tolerance calculation, and the range in which the shaft coupling action can be performed between the two couplings 122, 123, in other words, the rotation What is necessary is just to set it so that it may not be able to move relative to the rotation direction in transmitting the driving force effectively.
For example, there is a method in which the engagement amount of the spur gears 127 and 137 is set to be smaller than a module (a value obtained by dividing the diameter of the pitch circle by the number of teeth) of the spur gears 127 and 137.

Furthermore, in this example, as shown in FIG. 9A, the coupling 121 has a sufficient allowance in the direction intersecting the driving force direction Px received by the outer coupling 123 from the helical gear transmission mechanism 150. It is preferable to secure α. Specifically, as shown in FIG. 9B, the play margin α of the meshing portion between the spur gear 137 of the outer coupling 123 and the spur gear 127 of the inner coupling 122 is related to the driving force direction Px ( Assuming that αx is a play allowance along the x direction in the figure) and αy is a play allowance along a direction intersecting with the driving force direction Px (in this example, a direction orthogonal to the direction: corresponds to the y direction in the figure), αy> αx It is preferable to select so as to satisfy.
At this time, a gap g corresponding to the play allowance α is required between the cylindrical shaft portions 133 and 134 of the outer coupling 123 and the holding holes 135 and 136 of the coupling holding frame 130. May be set so that a dimension perpendicular to the driving force direction Px is larger than a dimension in the driving force direction Px.
According to this aspect, for example, in a mode in which the allowance is secured only in the driving force direction Px that the outer coupling 123 receives from the helical gear transmission mechanism 150, the outer coupling 123 and the inner coupling are affected by the driving force. Although the space required for the centering action between the two elements 122 is easily damaged, as described above, if the play allowance αy is secured in the direction orthogonal to the driving force direction Px, the space between the two elements can be reduced. It becomes easy to secure the space required for the centering action.

-Stopper structure-
In the present embodiment, the transport roll 84f has a thrust-free function. However, stopper structures for regulating the amount of axial movement of the transport roll 84f are provided at both ends of the drive roll 101, respectively.
First, as shown in FIG. 10A, an E-ring 170 as a stopper is provided at the end of the support shaft 103 on the side where the drive transmission mechanism 120 is not provided among the drive rolls 101 of the transport roll 84f. The drive roll 101 can move toward the drive transmission mechanism 120 until 170 comes into contact with the flange 104 a of the bearing 104.
As shown in FIG. 10B, a link arm 113 which also functions as a stopper is provided at an end of the support shaft 103 of the drive roll 101 which is located on the drive transmission mechanism 120 side. The drive roll 101 can move toward the side opposite to the drive transmission mechanism 120 until the roller abuts against the flange 105 a of the bearing 105.
Note that the stopper structure is not limited to these embodiments, and for example, as shown in FIG. 10B, the stopper structure is adjacent to a portion where the inner coupling 122 and the outer coupling 123 are engaged with the spur gears 127 and 137. A stepped portion 175 and a stepped portion 176 against which the stepped portion 175 abuts are formed at the locations, and the stepped portion 175 is driven until the stepped portion 175 abuts against the stepped portion 176 instead of the stopper structure using the E-ring 170 in FIG. The roll 101 may be movable to the drive transmission mechanism 120 side.

Next, the transporting behavior of the sheet by the transporting device according to the present embodiment will be described.
Now, as shown in FIGS. 2 and 3A, the paper S is supplied from the paper supply devices 81 and 82 or the manual paper supply device 98, and the paper S passes through the transport roll 84f of the vertical transport path 83. It is assumed that the position alignment roll 85 has been reached.
At this time, the rotational drive force from the drive motor 160 is transmitted to the transport roll 84f via the drive transmission mechanism 120. Specifically, the rotational driving force from the driving motor 160 is transmitted to the driving roll 101 via the helical gear transmission mechanism 150 and the coupling 121.
In this example, up to the coupling 121, the rotational driving force of the drive motor 160 is transmitted via the helical gear train 151 (the helical gears 151a to 151c) of the helical gear transmission mechanism 150, and the coupling 121 is an inner coupling. Since the spur gears 127 and 137 are engaged between the gear 122 and the outer coupling 123, the rotational driving force transmitted by the helical gear train 151 is transmitted to the outer coupling 123 and the spur gears 137 and 127. Is transmitted to the inner coupling 122 and further to the drive roll 101 connected to the inner coupling 122.
As described above, in this example, up to the coupling 121, the rotational driving force of the drive motor 160 is transmitted via the helical gear train 151 (the helical gears 151a to 151c) of the helical gear transmission mechanism 150. As compared with the embodiment using a drive transmission mechanism using a spur gear train, the higher meshing ratio of the helical gear train 151 reduces noise and suppresses the generation of vibration that affects image transfer by the secondary transfer device 50. .

Further, in the present embodiment, when the leading end of the sheet S abuts on the position alignment roll 85, the driving roll 101 and the driven roll 102 of the transport roll 84f are caused by the stress in the twist direction generated in the loop portion Sa of the sheet S. Thrust force acts.
At this time, since the coupling 121 is in a mode in which the inner coupling 122 and the outer coupling 123 are engaged with the spur gears 137 and 127, the inner coupling 122 is in the axial direction of the transport roll 84f with respect to the outer coupling 123. The drive roll 101 connected to the inner coupling 122 moves in the axial direction by the above-described thrust force, and further, the driven roll 102 connected to the drive roll 101 by the link arm 113 is moved. It moves in the axial direction in conjunction with the drive roll 101. Thereby, the twist generated in the sheet S is eliminated.

In this state, the spur gears 137 and 127 between the outer and inner elements of the coupling 121 mesh with a play allowance α, and hold the cylindrical shaft portions 133 and 134 of the outer coupling 123 and the coupling holding frame 130. Since the gap g corresponding to the play allowance α is provided between the holes 135 and 136, the coupling 121 can perform the centering action by the amount of play between the coupling 121 and the coupling holding frame 130.
The meshing portion of the spur gears 137, 127 between the outer and inner elements of the coupling 121 functions as a sliding portion that slides along the axial direction (corresponding to sliding movement), but the spur gears 137, 127 Since the above-mentioned play allowance α is ensured in the meshing portion, the sliding portion changes from static friction to dynamic friction, and the sliding resistance in the thrust direction is reduced accordingly.
In particular, in the present embodiment, the play allowance αy intersects with the driving force direction Px received by the outer coupling 123 from the helical gear transmission mechanism 150 (in this example, the direction orthogonal to the driving force direction) (see FIG. 9B). Is preferable in that the alignment is easily performed.

◎ Embodiment 2
FIG. 11 is an explanatory diagram illustrating a main part of the transport device according to the second embodiment.
In the figure, the basic configuration of the transport apparatus 100 uses a transport roll 84f having the same configuration as that of the first embodiment, but the drive transmission mechanism 120 is different from that of the first embodiment. Note that components similar to those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof is omitted here.
In this example, the drive transmission mechanism 120 includes a coupling 121 as a shaft coupling means for movably connecting the drive roll 101 of the transport roll 84f in the axial direction, and a rotational drive from a drive motor 160 to the coupling 121. And a helical gear transmission mechanism 150 that transmits a force. The helical gear transmission mechanism 150 includes a plurality of helical gear trains 151 (for example, helical gears 151a to 151c). The helical gear 151 c is different from the first embodiment and is separate from the outer coupling 123 of the coupling 121 and is provided coaxially with the outer coupling 123.
Therefore, also in the present embodiment, similarly to the first embodiment, the rotational driving force from the drive motor 160 is transmitted to the coupling 121 via the helical gear train 151 of the helical gear transmission mechanism 150.

  DESCRIPTION OF SYMBOLS 1 ... Conveying means, 1a, 1b ... Conveying member, 2 ... Drive transmitting means, 3 ... Drive source, 4 ... Shaft coupling means, 5 ... Inner coupling element, 6 ... Outer coupling element, 7 ... Helical gear transmission means, 8 ... Helical gear train, 9: coupling holder, 10: medium, 11: medium aligning device, 12: transport device, 15: stopper means, α: play allowance, g: gap

Claims (12)

Conveying means including a pair of conveying members capable of pinching and conveying the medium and moving in the axial direction,
A drive transmission unit provided at an axial end of one of the transport members of the pair of transport members to drive the transport member;
With
The drive transmission unit includes an inner joint element fixed to an axial end of the one transfer member and an outer joint element that holds the inner joint element so as to be movable in the axial direction. Shaft coupling means for movably coupling with respect to the direction,
A helical gear transmitting means having a plurality of helical gear trains for transmitting a rotational driving force from a driving source, and transmitting the rotational driving force from the driving source to an outer joint element of the shaft coupling means via the helical gear train. And a transport device comprising: The transfer device according to claim 1,
The shaft coupling means has a play allowance in which eccentricity due to a shift in the center position of the outer joint element and the inner joint element is allowed, and the outer joint element and the joint holding portion holding the outer joint element have an allowance. A transfer device having a gap corresponding to the play allowance therebetween. The transport device according to claim 2,
The play allowance of the shaft coupling means is larger than the deviation amount of the center position of the outer joint element and the inner joint element by a tolerance calculation, and is set in a range where the shaft coupling action can be performed between the two elements. Transfer device. The transfer device according to claim 1,
The transfer device according to claim 1, wherein the outer joint element and the inner joint element are associated with each other so that the outer joint element and the inner joint element can move relative to each other in the axial direction and cannot move relative to the rotational direction. The transport device according to claim 4,
The said coupling device is a conveyance apparatus characterized by comprising the spur gear in which the said outer joint element and the said inner joint element mesh relatively movably with respect to an axial direction. The transfer device according to claim 5,
A transport device wherein the allowance of the shaft coupling means is set such that the engagement amount of the spur gear falls within a range smaller than that of the module of the spur gear. The transfer device according to claim 1,
The helical gear transmission means, wherein the center of the helical gear located at the last stage of the helical gear train is concentric with the outer joint element of the shaft coupling means. The transport device according to claim 1 or 7,
The helical gear transmission means is characterized in that a helical gear located at the last stage of the helical gear train is integrally provided on an outer peripheral portion of an outer joint element of the shaft coupling means. The transfer device according to claim 1,
The transfer device according to claim 1, wherein the shaft coupling means has the play allowance in a direction intersecting a driving force direction received by the outer coupling element from the helical gear transmission means. The transport device according to claim 9,
The shaft coupling means has a gap corresponding to the play allowance between the outer joint element and a joint holding portion that holds the outer joint element, and the gap is defined by the outer joint element from the helical gear transmission means. A transport device characterized in that a dimension perpendicular to the driving force direction is made larger than a dimension in the driving force direction to be received. The transfer device according to claim 1,
The transfer device according to claim 1, wherein the shaft coupling means has stopper means for regulating the axial position between the outer joint element and the inner joint element. A medium aligning device that transports the medium after aligning the medium,
The medium according to claim 1, wherein the medium is transported upstream of the medium alignment device in a transport direction of the medium, and the medium is transported movably in a thrust direction when the medium is aligned by the medium alignment device. And a transport device.

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