JP2020003004A - Transmission device - Google Patents

Abstract

To appropriately apply tension to a rotating member in a transmission device.SOLUTION: A transmission device 1 comprises a first pulley 10, a second pulley 20, a belt 30 (rotating member), and a tension application part 40. The belt 30 is laid on the first pulley 10 and the second pulley 20, and rotates. The tension application part 40 comprises a first pressing roller 41 (first pressing part), a second pressing roller 42 (second pressing part), and a torsion spring 43 (biasing means). The first pressing roller 41 applies tension to the belt 30 by pressing a first portion 30a out of the first portion 30a and a second portion 30b of the belt 30 opposed to each other between the first pulley 10 and the second pulley 20. The second pressing roller 42 applies tension to the belt 30 by pressing the second portion 30b. The torsion spring 43 biases the first pressing roller 41 and the second pressing roller 42 toward the belt 30.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a transmission including a tension applying unit.

  Conventionally, for example, in a transport device, power is transmitted from a pulley of a motor shaft to a pulley of a transport roller shaft by a belt. A driving device that presses a roller against a belt by a leaf spring to apply tension to the belt is known (for example, see Patent Document 1).

JP 2000-355437 A

  By the way, the tension applying portion that presses a rotating member such as a belt or a chain is more suitable for applying tension to the rotating member on the tip side in the rotation direction of a driving pulley (for example, a pulley of a motor shaft). Rather than applying tension to the rotating member on the rear end side in the rotating direction, the tension can be applied more appropriately so that the rotating member does not loosen or teeth jump.

  However, particularly when the driving pulley rotates in both directions, depending on the rotation direction of the driving pulley, the tension applying unit applies the tension to the rotating member at the rear end side in the rotation direction of the driving pulley. become. Therefore, tension cannot be appropriately applied to the rotating member. As a result, there is a possibility that the rotating member may be loosened or the teeth may jump. Even when the driving pulley does not rotate in both directions, if tension is applied to the rotating member only at one of the leading and trailing ends in the rotating direction of the driving pulley, loosening of the rotating member and teeth Jumping and the like may occur.

  An object of the present invention is to provide a transmission that can appropriately apply tension to a rotating member.

  In one aspect, the transmission device includes a first pulley, a second pulley, a rotating member that is wound around the first pulley and the second pulley, and that rotates, the first pulley and the second pulley. A first pressing portion that applies tension to the rotating member by pressing the first portion of the first portion and the second portion of the rotating member that face each other between the second pulleys; A second pressing portion that applies tension to the rotating member by pressing the second portion, and a biasing force that biases the first pressing portion and the second pressing portion toward the rotating member. And a tension applying part having means.

  According to the above aspect, it is possible to appropriately apply tension to the rotating member.

It is a perspective view showing the conveyance device provided with the transmission concerning a 1st embodiment. FIG. 2 is an enlarged perspective view of a portion A in FIG. 1. FIG. 2 is an enlarged exploded perspective view of a part A in FIG. 1. It is a front view showing the transmission concerning a 1st embodiment. It is a rear view showing the transmission concerning a 1st embodiment. It is a perspective view showing the transmission concerning a 2nd embodiment. It is a front view showing the transmission concerning a 2nd embodiment. It is a rear view showing the transmission concerning a 2nd embodiment. It is a perspective view showing the transmission concerning a 3rd embodiment. It is a front view showing the transmission concerning a 3rd embodiment. It is a rear view showing the transmission concerning a 3rd embodiment.

  Hereinafter, transmissions 1 to 3 according to first to third embodiments of the present invention will be described with reference to the drawings.

<First embodiment>
FIG. 1 is a perspective view illustrating a transfer device 100 including the transmission 1 according to the first embodiment.

FIG. 2 is an enlarged perspective view of the portion A in FIG. 1, and FIG. 3 is an enlarged exploded perspective view of the portion A in FIG.
As shown in FIG. 1, the transport device 100 includes a transmission device 1, transport rollers 101 and 102, a transport roller shaft 103, a motor 104, and a frame 105. Is transported. When the transport device 100 is arranged in the printing apparatus in this way, the transmission 1 is mounted on the paper transport unit (transport device 100) of the printing device together with the motor 104 that rotates forward and reverse to reverse the transport direction of the sheet. As described later, the belt 30 of the transmission 1 may rotate in both directions (clockwise and counterclockwise in FIGS. 4 and 5).

  The transport rollers 101 and 102 are provided on a common transport roller shaft 103. The power is transmitted from the motor 104 to the transport roller shaft 103 by the transmission device 1. The transport roller shaft 103 passes through the frame 105 via a bearing. The motor 104 is fixed to the frame 105 by fixing screws 104b shown in FIG.

  The motor 104 is an example of a drive source (actuator) that generates power transmitted by the transmission device 1, and the transport roller shaft 103 is an example of a member to which power is transmitted from the motor 104 via the transmission device 1. The transport device 100 may include a plurality of transport roller shafts 103 to which power is transmitted from one or more motors 104.

FIG. 4 is a front view showing the transmission 1, and FIG. 5 is a rear view showing the transmission 1.
As shown in FIGS. 2 to 5, the transmission 1 includes a first pulley 10, a second pulley 20, a belt 30, and a tension applying unit 40.

  The first pulley 10 is a drive-side pulley, and the power of the first pulley 10 is transmitted to the second pulley 20. As shown in FIG. 2, the first pulley 10 is provided on the output shaft 104a of the motor 104. Further, the second pulley 20 is provided on the transport roller shaft 103. However, the first pulley 10, which is a drive-side pulley, does not need to be located coaxially with the output shaft 104a, and may be provided on a shaft to which power is transmitted from the output shaft 104a (motor 104).

  The belt 30 is an example of a rotating member that is stretched over the first pulley 10 and the second pulley 20 and that rotates in, for example, both directions (clockwise and counterclockwise in FIGS. 4 and 5). The belt 30 is, for example, a toothed belt that meshes with teeth provided on the outer peripheral surfaces of the first pulley 10 and the second pulley 20. However, the rotating member may be any member as long as it is bridged and rotated between the first pulley 10 and the second pulley 20, and may be another belt, a chain, or the like.

  The tension applying section 40 is a tensioner having a first pressing roller 41, a second pressing roller 42, a torsion spring 43, a connecting arm 44, an arm rotation shaft 45, and a spring hook 46.

  The first pressing roller 41 is rotatably disposed around a roller shaft 41 a fixed to one end of the connecting arm 44 as a rotation center axis. The first pressing roller 41 is formed of a first portion 30a that is an upper portion of the belt 30 and a second portion 30b that is a lower portion of the belt 30 that are opposed to each other between the first pulley 10 and the second pulley 20. The first portion 30a is pressed from outside the belt 30. As described above, the first pressing roller 41 functions as an example of a first pressing portion that applies tension to the belt 30.

  The second pressing roller 42 is rotatably disposed around a roller shaft 42 a fixed to the other end of the connection arm 44 as a rotation center axis. The second pressing roller 42 presses the second portion 30 b of the first portion 30 a and the second portion 30 b of the belt 30 from outside the belt 30. As described above, the second pressing roller 42 functions as an example of a second pressing unit that applies tension to the belt 30.

  Note that the first pressing roller 41 and the second pressing roller 42 are, for example, the same members and have the same diameter.

  The torsion spring 43 is an example of an urging unit that urges the first pressing roller 41 and the second pressing roller 42 toward the belt 30.

  As shown in FIGS. 2 and 3, the torsion spring 43 is wound around an arm rotation shaft 45 that is a rotation center axis of the connection arm 44. A movable end 43a, which is an arm at one end of the torsion spring 43, is hooked on a rotatable connecting arm 44, and a fixed end 43b, which is an arm at the other end of the torsion spring 43, is provided with a non-rotatable spring hook 46. It is hooked on the notch 46a. Thereby, the torsion spring 43 rotates the connecting arm 44 clockwise in FIG. 4 (front view) and counterclockwise in FIG. 5 (rear view), and causes the first pressing roller 41 and the second pressing roller 42 to rotate. It is urged toward the belt 30.

  The urging means for urging the first pressing roller 41 and the second pressing roller 42 toward the belt 30 may be an elastic body other than the torsion spring 43 or the like. When the connecting arm 44 is omitted and the first pressing roller 41 and the second pressing roller 42 are not connected to each other, an urging means for urging the first pressing roller 41 toward the belt 30. And urging means for urging the second pressing roller 42 toward the belt 30 may be separately arranged.

  The connecting arm 44 is, for example, a thin plate-shaped member, and is rotatably fixed to a non-rotatable arm rotation shaft 45 via a bearing. In the connection arm 44, the first pressing roller 41 provided at one end, the second pressing roller 42 provided at the other end, and the arm rotation shaft 45 are arranged in a straight line. Further, the first pressing roller 41 is located closer to the second pulley 20 than the arm rotation shaft 45, and the second pressing roller 42 is located closer to the first pulley 10 than the arm rotation shaft 45.

  The rear end of the arm rotation shaft 45 is fixed to a frame 105 shown in FIG. As shown in FIGS. 2 and 3, a spring hook 46 is fixed to a front end of the arm rotation shaft 45 by a fixing screw 45 a in a state where the torsion spring 43 is interposed between the arm rotation shaft 45 and the connecting arm 44. . As shown in FIG. 5, the arm rotation shaft 45 is disposed at the center of a line (dashed line) connecting the rotation center axis of the first pulley 10 and the rotation center axis of the second pulley 20.

  The spring hook 46 is, for example, a thin plate-shaped member, has an oval-shaped hole inserted into an oval-shaped protrusion provided at the front end of the arm rotation shaft 45, and is fixed from the front side. It is fixed to the arm rotation shaft 45 by a screw 45a. Thus, the spring hook 46 is arranged so as not to rotate similarly to the arm rotation shaft 45. As described above, the fixed end 43b of the torsion spring 43 is hooked on the notch 46a provided on the spring hook 46.

  Here, as shown in FIG. 5, the distance (center distance) L11 between the roller shaft 41a of the first pressing roller 41 and the arm rotating shaft 45 is determined by the distance between the roller shaft 42a of the second pressing roller 42 and the arm rotating shaft. 45 (the center-to-center distance) L12. In other words, the distance from the arm rotation shaft 45 is such that the position where the first pressing roller 41 presses the belt 30 is longer than the position where the second pressing roller 42 presses the belt 30.

  This is because the diameter (for example, pitch circle diameter) of the first pulley 10 is smaller than the diameter (for example, pitch circle diameter) of the second pulley 20, and if the distance L11 and the distance L12 are the same, the second This is because the first pressing roller 41 rotating toward the pulley 20 presses the belt 30 with a stronger pressing force than the second pressing roller 42. Therefore, the distance L11 is longer than the distance L12 so that the pressing force on the belt 30 approaches the first pressing roller 41 and the second pressing roller 42 evenly. When the diameter of the first pulley 10 and the diameter of the second pulley 20 are the same, the distance L11 and the distance L12 are the same, and the distance from the arm rotation shaft 45 is the first pressing roller. It is preferable that the pressing position of the belt 30 by the 41 and the pressing position of the belt 30 by the second pressing roller 42 be the same.

  However, the diameter of the first pulley 10 and the diameter of the second pulley 20 are different from each other, and the distance from the arm rotation shaft 45 depends on the pressing position of the belt 30 by the first pressing roller 41 and the second pressing roller 42 4 and FIG. 5, the arm rotation shaft 45 is moved from the center position between the rotation center axis of the first pulley 10 and the rotation center axis of the second pulley 20, , The pressing force on the belt 30 can be made to approach the first pressing roller 41 and the second pressing roller 42 evenly.

  In the first embodiment described above, the transmission 1 includes the first pulley 10, the second pulley 20, the belt 30 as an example of a rotating member, and the tension applying section 40. The belt 30 rotates while being bridged between the first pulley 10 and the second pulley 20. The tension applying unit 40 includes a first pressing roller 41 as an example of a first pressing unit, a second pressing roller 42 as an example of a second pressing unit, and a torsion spring 43 as an example of an urging unit. And The first pressing roller 41 presses the first portion 30a of the first portion 30a and the second portion 30b of the belt 30 facing each other between the first pulley 10 and the second pulley 20. Tension is applied to the belt 30. The second pressing roller 42 applies tension to the belt 30 by pressing the second portion 30b. The torsion spring 43 urges the first pressing roller 41 and the second pressing roller 42 toward the belt 30.

  Thereby, tension can be applied to both the first portion 30a and the second portion 30b of the belt 30 that face each other by the first pressing roller 41 and the second pressing roller 42. In this way, by applying tension to the belt 30 at both the leading end and the trailing end in the rotation direction of the first pulley 10 that is the driving pulley, the belt 30 is rotated particularly in both directions. 30 can be appropriately tensioned. As described above, according to the first embodiment, the belt 30 can be appropriately tensioned. Thus, for example, it is possible to prevent the belt 30 from being loosened or tooth jumping, which is particularly likely to occur when the belt 30 rotates in the normal rotation direction, stops, and then rotates in the reverse direction.

  Further, in the first embodiment, the tension applying section 40 further includes a rotatable connection arm 44 that connects the first pressing roller 41 and the second pressing roller 42. The torsion spring 43 urges the first pressing roller 41 and the second pressing roller 42 toward the belt 30 by rotating the connecting arm 44. Therefore, when the torsion spring 43 rotates the connection arm 44, both the first pressing roller 41 and the second pressing roller 42 can be urged. Further, the arm rotation shaft 45 can be arranged in the belt 30. Therefore, tension can be applied to the belt 30 with a small number of components and a space-saving configuration. Thus, for example, the transmission 1 can be arranged in a narrow space where the small motor 104 and the transport roller shaft 103 are close to each other.

  In the first embodiment, the diameter (for example, pitch circle diameter) of the first pulley 10 is different from the diameter (for example, pitch circle diameter) of the second pulley 20, and the pressing force on the belt 30 is equal to the first pressure. The distance from the arm rotation shaft 45, which is the rotation center axis of the connecting arm 44, is set so that the pressing roller 41 and the second pressing roller 42 are evenly close to each other. And the pressing position of the belt 30 by the pressing roller 42. Alternatively, the arm rotation shaft 45 is connected between the rotation center axis of the first pulley 10 and the second pulley 20 so that the pressing force against the belt 30 approaches the first pressing roller 41 and the second pressing roller 42 equally. It is arranged shifted from the center position with respect to the rotation center axis. Therefore, the first pressing roller 41 (one pressing portion) rotating toward the second pulley 20 (a large-diameter pulley) presses the belt 30 before the second pressing roller 42 (the other pressing portion). As a result, it is possible to prevent the pressing force of the first pressing roller 41 against the belt 30 from becoming stronger than the pressing force of the second pressing roller 42 against the belt 30. Therefore, the tension can be more appropriately applied to the belt 30.

<Second embodiment>
FIG. 6 is a perspective view illustrating the transmission 2 according to the second embodiment, FIG. 7 is a front view illustrating the transmission 2, and FIG. 8 is a rear view illustrating the transmission 2.

  In the second embodiment, the belt 30 is pressed from the inside instead of the tension applying section 40 in the first embodiment having the first pressing roller 41 and the second pressing roller 42 for pressing the belt 30 from the outside. A tension applying section 50 having a first pressing roller 51 and a second pressing roller 52 is disposed. Other configurations can be the same as those of the first embodiment, and thus detailed description is omitted.

  As shown in FIGS. 4 to 6, the transmission 2 includes a first pulley 10, a second pulley 20, a belt 30, and a tension applying unit 50.

  Similar to the tension applying unit 40 in the first embodiment, the tension applying unit 50 includes a first pressing roller 51 including a roller shaft 51a, a second pressing roller 52 including a roller shaft 52a, and a movable end 53a. The tensioner includes a torsion spring 53 including a fixed end 53b, a connecting arm 54, an arm rotation shaft 55 including a fixing screw 55a, and a spring hook 56 including a notch 56a.

  In the second embodiment, the torsion spring 53 connects the connecting arm 54 counterclockwise in FIG. 7 (front view) and clockwise in FIG. 8 (rear view), opposite to the torsion spring 43 in the first embodiment. By rotating, the first pressing roller 51 and the second pressing roller 52 are urged toward the belt 30.

  Then, the first pressing roller 51 presses the first portion 30 a of the belt 30 from inside the belt 30. Further, the second pressing roller 52 presses the second portion 30 b from inside the belt 30.

  As shown in FIG. 8, the roller shaft 51 a of the first pressing roller 51 and the arm rotation shaft 55 are arranged such that the pressing force against the belt 30 approaches the first pressing roller 51 and the second pressing roller 52 evenly. (Center distance) L21 is longer than the distance (center distance) L22 between the roller shaft 52a of the second pressing roller 52 and the arm rotation shaft 55. That is, as for the distance from the arm rotation shaft 55, the position where the belt 30 is pressed by the first pressing roller 51 is longer than the position where the belt 30 is pressed by the second pressing roller 52.

  However, the diameter of the first pulley 10 and the diameter of the second pulley 20 are different from each other, and the distance from the arm rotation shaft 55 is different from the position where the first pressing roller 51 presses the belt 30 and the second pressing roller 52. 7 and FIG. 8, the arm rotation shaft 55 is moved from the center position between the rotation center axis of the first pulley 10 and the rotation center axis of the second pulley 20 even if it is the same as the pressing position of the belt 30. , The pressing force on the belt 30 can be made to approach the first pressing roller 51 and the second pressing roller 52 evenly.

  According to the above-described second embodiment, the same effect as that of the above-described first embodiment, that is, the effect of appropriately applying tension to the belt 30 can be obtained.

  In the second embodiment, the first pressing roller 51 and the second pressing roller 52 press the belt 30 from inside the belt 30. Therefore, the first pressing roller 51 and the second pressing roller 52 can be arranged inside the belt 30. Therefore, tension can be applied to the belt 30 with a space-saving configuration using the space in the belt 30.

<Third embodiment>
FIG. 9 is a perspective view illustrating the transmission 3 according to the third embodiment, FIG. 10 is a front view illustrating the transmission 3, and FIG. 11 is a rear view illustrating the transmission 3.

  In the third embodiment, the belt 30 is pressed from the inside instead of the tension applying section 40 in the above-described first embodiment having the first pressing roller 41 and the second pressing roller 42 for pressing the belt 30 from the outside. A tension applying section 60 having a first pressing roller 61 for pressing the belt 30 and a second pressing roller 62 for pressing the belt 30 from the outside is disposed. Other configurations can be the same as those of the first embodiment, and thus detailed description is omitted.

  As shown in FIGS. 9 to 11, the transmission 3 includes a first pulley 10, a second pulley 20, a belt 30, and a tension applying unit 60.

  Similar to the tension applying section 40 in the first embodiment, the tension applying section 60 includes a first pressing roller 61 including a roller shaft 61a, a second pressing roller 62 including a roller shaft 62a, a movable end portion 63a, The tensioner has a torsion spring 63 including a fixed end 63b, a connecting arm 64, an arm rotation shaft 65 including a fixing screw 65a, and a spring hook 66 including a notch 66a.

  In the third embodiment, the connecting arm 64 is, for example, an L-shaped plate-like member, and both the first pressing roller 61 and the second pressing roller 62 are connected to the first pulley 10 (One example of one pulley).

  In the third embodiment, as in the first embodiment, the torsion spring 63 rotates the connecting arm 64 clockwise in FIG. 10 (front view) and counterclockwise in FIG. 11 (rear view). The first pressing roller 61 and the second pressing roller 62 are urged toward the belt 30.

  Then, the first pressing roller 61 presses the first portion 30 a of the belt 30 from inside the belt 30. The second pressing roller 62 presses the second portion 30b from outside the belt 30.

  As shown in FIG. 11, the distance (center distance) L31 between the roller shaft 61a of the first pressing roller 61 and the arm rotation shaft 65 is determined by the distance between the roller shaft 62a of the second pressing roller 62 and the arm rotation shaft 65. It is longer than the distance (center-to-center distance) L32. The distance from the arm rotation shaft 65 is such that the position where the belt 30 is pressed by the first pressing roller 61 is longer than the position where the belt 30 is pressed by the second pressing roller 62. However, in the third embodiment, the first pressing roller 61 is located closer to the first pulley 10 than the second pressing roller 62 and has a smaller diameter than the second pulley 20. Therefore, in order for the pressing force on the belt 30 to be evenly closer between the first pressing roller 61 and the second pressing roller 62, the distance from the arm rotation shaft 65 is set to the belt 30 by the first pressing roller 61. May be shorter than the pressing position of the belt 30 by the second pressing roller 62.

  According to the third embodiment described above, the same effect as that of the above-described first embodiment, that is, an effect of appropriately applying tension to the belt 30 can be obtained.

  In the third embodiment, the first pressing roller 61 presses the belt 30 from inside the belt 30, and the second pressing roller 62 presses the belt 30 from outside the belt 30. As described above, one of the first pressing roller 61 and the second pressing roller 62 (the first pressing roller 61) is arranged in the space inside the belt 30, and the other (the second pressing roller 62) is connected to the belt 30. By arranging in the space outside of the transmission 30, it is possible to perform the arrangement according to the space around the transmission device 3. Therefore, according to the third embodiment, the degree of freedom in designing the transmission 3 can be increased.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying constituent elements in an implementation stage without departing from the scope of the invention. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, all components shown in the embodiments may be appropriately combined. Of course, various modifications and applications are possible without departing from the spirit of the invention. Hereinafter, the invention described in the claims at the time of filing the application of the present application is additionally described.

[Appendix 1]
A first pulley;
A second pulley;
A rotating member that is wound around the first pulley and the second pulley and rotates;
The tension is applied to the rotating member by pressing the first portion of the first and second portions of the rotating member that are opposed to each other between the first pulley and the second pulley. A first pressing portion, a second pressing portion that applies tension to the rotating member by pressing the second portion, and the first pressing portion and the second pressing portion to the rotating member. And a tension applying portion having an urging means for urging toward the transmission.
[Appendix 2]
The tension applying unit further includes a rotatable connection arm that connects the first pressing unit and the second pressing unit,
The transmission according to claim 1, wherein the urging means urges the first pressing portion and the second pressing portion toward the rotating member by rotating the connection arm.
[Appendix 3]
The diameter of the first pulley is different from the diameter of the second pulley,
The distance from the arm rotation axis, which is the rotation center axis of the connecting arm, is set to the first pressing portion so that the pressing force against the rotating member approaches the first pressing portion and the second pressing portion evenly. Or the pressing position of the rotating member by the second pressing portion is different from each other, or the arm rotation axis is the rotation center axis of the first pulley and the rotation of the second pulley. 3. The transmission according to claim 2, wherein the transmission is shifted from a center position with respect to the center axis.

1, 2, 3 Transmission 10 First pulley 20 Second pulley 30 Belt 30a First part 30b Second part 40, 50, 60 Tension applying part 41, 51, 61 First pressing roller 41a, 51a , 61a Roller shafts 42, 52, 62 Second pressing rollers 42a, 52a, 62a Roller shafts 43, 53, 63 Torsion springs 43a, 53a, 63a Movable end 43b, 53b, 63b Fixed end 44, 54, 64 Connection Arms 45, 55, 65 Arm rotating shafts 45a, 55a, 65a Fixing screws 46, 56, 66 Spring hooks 46a, 56a, 66a Notch 100 Conveying device 101, 102 Conveying roller 103 Conveying roller shaft 104 Motor 104a Output shaft 104b Fixing screw 105 frames

Claims (3)

A first pulley;
A second pulley;
A rotating member that is wound around the first pulley and the second pulley and rotates;
The tension is applied to the rotating member by pressing the first portion of the first and second portions of the rotating member that are opposed to each other between the first pulley and the second pulley. A first pressing portion, a second pressing portion that applies tension to the rotating member by pressing the second portion, and the first pressing portion and the second pressing portion to the rotating member. And a tension applying portion having an urging means for urging toward the transmission. The tension applying unit further includes a rotatable connection arm that connects the first pressing unit and the second pressing unit,
The transmission device according to claim 1, wherein the urging unit urges the first pressing unit and the second pressing unit toward the rotating member by rotating the connection arm. The diameter of the first pulley is different from the diameter of the second pulley,
The distance from the arm rotation axis, which is the rotation center axis of the connecting arm, is set to the first pressing portion so that the pressing force against the rotating member approaches the first pressing portion and the second pressing portion evenly. Or the pressing position of the rotating member by the second pressing portion is different from each other, or the arm rotation axis is the rotation center axis of the first pulley and the rotation of the second pulley. The transmission according to claim 2, wherein the transmission is shifted from a center position with respect to a center axis.