JPH10169726A - Gear device - Google Patents

Abstract

(57) [Summary] To provide a gear device capable of automatically adjusting backlash. A first shaft (2) provided with a first gear (1), a second gear (3) meshing with the first gear (1), and a third gear (4) rotating together with the second gear (3) are provided. Second shaft 5
And a third shaft provided with a fourth gear that meshes with the third gear 4. On the second shaft 5, a gear mounting shaft portion 5a for rotatably mounting the second and third gears 3, 4 and mounting members 9a, 9 located on both sides of the gear mounting shaft portion 5a.
b are provided with mounting shaft portions 5b and 5c that are rotatably mounted.
The mounting shaft portions 5b and 5c are concentric, and the gear mounting shaft portion 5a
Is eccentric with respect to the mounting shafts 5b and 5c. A rotation urging force generating mechanism 13 for rotating the gear mounting shaft 5a about the mounting shafts 5b and 5c in a direction for adjusting the backlash between the first gear 1 and the second gear 3 is provided. .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear device used as a speed reducer or the like.

[0002]

2. Description of the Related Art In a gear device, backlash generated at a meshing portion of gears is an inevitable problem. Conventional methods for adjusting backlash include a static method and a dynamic method, and specific examples thereof include the following method.

(A) A method of adjusting backlash by shifting a conical gear such as a bevel gear or a taper gear in the axial direction.

(B) A method of adjusting the backlash by moving the meshing gear in parallel in the direction in which the center distance decreases.

(C) A method of adjusting the backlash by reducing the center distance of the gears that mesh with each other by an urging means such as a spring.

[0006]

In adjusting the backlash of a gear device, the accuracy of final assembly adjustment affects the amount of backlash, tooth wear and life.

However, in the above-described conventional methods, there is a problem that the assembly and adjustment are not easy and the wear and the life of the gear are affected by the misalignment between the respective shafts and the magnitude of the preload due to the adjustment. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a gear device having high precision and good quality, and capable of easily adjusting backlash.

Another object of the present invention is to provide a gear device which can maintain the backlash so as to always be small.

Another object of the present invention is to provide a gear device which can easily maintain a state set to reduce backlash.

[0011]

SUMMARY OF THE INVENTION The present invention provides a first shaft provided with a first gear provided at the last stage of a gear train, a second gear meshing with the first gear, and the second gear. To improve a gear device including a second shaft provided with a third gear rotating together with the third gear, and a third shaft provided with a fourth gear meshing with the third gear. One or more shafts provided with a reduction gear may be arranged in front of the third shaft. If the third shaft is, for example, a driving shaft connected to an output shaft of a motor, the fourth gear is a driving shaft gear, the second shaft is an intermediate shaft, and is provided on the second shaft. The second and third gears are intermediate gears and transmission gears. The first shaft serves as a driven shaft, and the first gear provided on the first shaft serves as a driven gear.

The second shaft used in the present invention includes the second and third shafts.
A gear mounting shaft portion rotatably mounted with the gears, and a pair of mounting shaft portions located on both sides of the gear mounting shaft portion and rotatably mounted on a pair of mounting members, respectively. The pair of mounting shafts are concentric with each other, and the gear mounting shaft is configured to be eccentric with the pair of mounting shafts. In other words, the second shaft is configured such that the axis of the gear mounting shaft does not coincide with the axis of the pair of mounting shafts. Further, a rotation urging force for rotating the gear mounting shaft about the pair of mounting shafts in a direction for adjusting the backlash between the first gear and the second gear is applied to the second shaft. A rotation urging force generating mechanism is provided.

According to this structure, the rotation urging force generated by the rotation urging force generating mechanism is rotated in one rotation direction (backlash) about the pair of mounting shafts which are concentric with the second shaft. In the direction of adjustment). When the second shaft rotates by a predetermined angle with this force, the distance between the axis of the gear mounting shaft provided eccentrically to the pair of mounting shafts and the axis of the first shaft changes. This change in distance provides an adjustment to reduce or reduce backlash between the first gear and the second gear. Since the rotational urging force is constantly generated from the rotational urging force generating mechanism, the backlash adjustment is automatically performed at the stage of assembling the gear device. Also, even if the meshing surfaces of the gears are worn, the backlash adjustment for correcting the wear is automatically performed by the rotational urging force. As a result, according to the present invention, the backlash between the first gear and the second gear can always be kept small, and the backlash can be automatically adjusted, so that the adjustment of the backlash is troublesome. There is no advantage.

The rotation urging force generating mechanism used in the present invention may have any structure as long as it can apply a rotation urging force to the second shaft. For example, a pair of mounting shafts are provided with a pair of mounting shafts. A pair of coil springs are fitted to each other, one end of each of the pair of coil springs is fixed to a pair of mounting shafts, and the other end is fixed to a pair of mounting members. be able to. With such a configuration, the rotation urging force generating mechanism can be easily constituted only by the pair of coil springs, and it is not necessary to secure a special space for installing the rotation urging force generating mechanism. Further, the rotation urging force generating mechanism can be configured at low cost. Note that, theoretically, the rotation urging force can be generated by only one coil spring. However, if a pair of coil springs is used, the second shaft can be rotated in a well-balanced manner, and the unbalanced state can be obtained. It is possible to prevent rattling due to application of force.

As described above, if the third shaft is the driving shaft, the rotating power generating mechanism is provided to apply a rotating urging force to the intermediate shaft.

The use of a rotating urging force generating mechanism allows the backlash to be automatically adjusted. Even when the rotating urging force generating mechanism is not used, the pair of mounting shafts are made coaxial with each other. The basic idea of the present invention in which the gear mounting shaft is eccentric with the pair of mounting shafts, and the distance between the first shaft and the second shaft is adjusted by rotating the pair of mounting shafts. Can be used to adjust the backlash. In this case, instead of using the rotation urging force generating mechanism, the first gear (the driven gear of the driven shaft) and the second gear are rotated by rotating the gear mounting shaft around the pair of mounting shafts. A pair of mounting shafts of the second shaft (intermediate shaft) can be rotationally adjusted to a pair of mounting members and a pair of mountings so that backlash between the second shaft (intermediate shaft and intermediate gear) can be adjusted. What is necessary is just to mount so that positioning is possible with respect to a member. Here, the structure in which the pair of mounting shafts of the second shaft (intermediate shaft) are turned around the axis thereof is a structure in which the pair of mounting shafts can be rotationally adjusted to the pair of mounting members and positioned relative to the pair of mounting members. Although it can be moved, it is a structure in which a pair of mounting shafts can be fixed to a pair of mounting members at a predetermined position.

Also in this case, by rotating the gear mounting shaft about the pair of mounting shafts,
The backlash between the first gear and the second gear can be adjusted. When the adjustment is completed, the pair of mounting shafts can be positioned (fixed) with, for example, a lock screw. The positioning (fixing) of the pair of mounting shafts with respect to the pair of mounting members may be performed by positioning (fixing) at least one of the mounting shaft portions with respect to the one mounting member.

[0018]

1 and 2 show a first embodiment of a gear device according to the present invention. FIG. 1 is a cross-sectional view of the gear device, and FIG. 2 is this gear device. It is a front view which shows the positional relationship of each shaft and each gear.

In this gear device, a first shaft (driven shaft) 2 integrally provided with a first gear (driven gear) 1 provided at the last stage of a gear train, and a second gear meshing with the first gear 1 are provided. (Intermediate gear) 3 and the third gear 3 rotating together with the second gear 3
A second shaft (intermediate shaft) 5 rotatably provided with a gear (conduction gear) 4 and a third shaft (drive gear) 6 integrally provided with a fourth gear (drive gear) 6 meshing with the third gear 4. (A driving shaft) 7. The second and third gears 3 and 4 are formed integrally so as to be coaxial with each other in the axial direction. At the center of the second and third gears 3 and 4, a through hole 8 through which the second shaft 5 passes is provided. 9 is a gear box, and this gear box 9
It is composed of a box-shaped box body 9A having an open surface and a closing plate 9B for closing the opening of the box body 9A. A pair of opposed wall portions to which a plurality of shafts are attached among a plurality of wall portions constituting the gear box 9 constitute a pair of attachment members 9a and 9b, and a pair of opposed members connecting the pair of attachment members. The walls constitute a pair of side wall members 9c and 9d. The gear box 9 is fixed to, for example, a motor case using fixing means (not shown).

The second shaft 5 is provided with second and third gears 3, 4
Is rotatably mounted on the gear mounting shaft 5a, and a pair of mounting shafts located on both sides of the gear mounting shaft 5a and rotatably mounted in the holes 10a and 10b of the pair of mounting members 9a and 9b, respectively. 5b and 5c, and a contact portion 5d that is a stepped portion that contacts the inner surface of the mounting member 9a and restricts the second shaft 5 from being displaced in the axial direction. Such a second shaft 5 includes a pair of mounting shaft portions 5b,
5c are concentric with each other, and the gear mounting shaft 5a is decentered from the pair of mounting shafts 5b, 5c by a dimension d (that is, the axis C1 of the pair of mounting shafts 5b, 5c and the gear mounting shaft). The configuration is such that the axis C2 of the portion 5a does not coincide (see FIG. 2). In this example, the axis C2 of the gear mounting shaft 5a is located in a region between the axis C1 of the pair of mounting shafts 5b and 5c and the first axis C3. In this state, if the second shaft rotates in the clockwise direction, the axis C2 of the gear mounting shaft portion 5a and the axis of the first shaft 2 until the axes C1, C2, and C3 are aligned. The distance to C3 is reduced, and beyond this state the second
When the shaft further rotates clockwise, the gear mounting shaft portion 5a
The distance between the axis C2 of the first shaft 2 and the axis C3 of the first shaft 2 becomes large. In this example, the backlash is adjusted by rotating the second shaft in the clockwise direction so that the distance between the axis C2 of the gear mounting shaft portion 5a and the axis C3 of the first shaft 2 is reduced.

The second and third gears 3 and 4 have a ball bearing 11 interposed between the second gear 3 and the gear mounting shaft 5a, and have a ball bearing 11 between the third gear 4 and the gear mounting shaft 5a. With the metal bearing 12 interposed, the second bearing 5 is rotatable.

A rotational urging force for rotating the gear mounting shaft 5a about the pair of mounting shafts 5b and 5c in a direction for adjusting the backlash between the first gear 1 and the second gear 3. In order to apply (a force for rotating the second shaft in the clockwise direction in FIG. 2) to the second shaft 5, a rotation urging force generating mechanism 13 is provided. The rotation urging force generating mechanism 13 is configured using a pair of coil springs 14 and 15 fitted to a pair of mounting shafts 5b and 5c. One end 14a, 15a of each of the pair of coil springs 14, 15 has a pair of mounting shafts 5b, 5c.
And the other end 14b, 15b is connected to a pair of mounting members 9
a, 9b, and urges the second shaft 5 in the clockwise direction in FIG.

Both ends of the first shaft 2 are also connected to a pair of mounting members 9.
a and 9b rotatably supported by ball bearings 16a and 16b. Similarly, both ends of the third shaft 7 are rotatably supported by a pair of mounting members 9a and 9b by ball bearings (not shown).

In this embodiment, the first, second, and third shafts 2, 5, 7 and the first, second, third, and fourth gears 1, 3,
The reduction gear 17 is constituted by a gear train composed of 4 and 6.

As described above, the second shaft 5 is provided with the intermediate gear mounting shaft 5a eccentric with respect to the pair of mounting shafts 5b and 5c which are concentric with each other. Second
And the third gears 3 and 4 are rotatably mounted, and the gear mounting shaft 5a is connected to the pair of mounting shafts 5b and 5c in a direction in which backlash between the first gear 1 and the second gear 3 is adjusted. Is provided on the second shaft 5 by the rotation urging force generating mechanism 13 that applies a rotation urging force to the second shaft 5. A rotational biasing force in the direction of adjusting the backlash between the first gear 1 and the second gear 3 can always be applied, and the backlash between the first gear 1 and the second gear 3 is always kept small. can do. That is, the gear mounting shaft 5a existing between the pair of mounting shafts 5b and 5c is attached to the gear mounting shafts 5b and 5c.
Since the second gear 3 is arranged concentrically around the outer periphery of the gear mounting shaft 5a, the second shaft 5 is centered on the mounting shafts 5b and 5c. When rotated, the backlash between the first gear 1 and the second gear 3 can be adjusted according to the rotation angle. At this time, the pair of coil springs 14 and 15 urge the gear mounting shaft portion 5a to rotate in the direction in which the backlash is reduced, so that the backlash can always be kept small. Further, according to the turning urging force generating mechanism 13,
There is the advantage that backlash can be automatically adjusted, and no effort is required to adjust backlash.

FIG. 3 is a cross-sectional view of a second embodiment of the gear device according to the present invention. Parts corresponding to those in FIG. 1 are denoted by the same reference numerals. The positional relationship between each shaft and each gear of the gear device of the second example is the same as in FIG. 2 described above. In this gear device, the pair of mounting shafts 5b and 5c of the second shaft 5 rotate the gear mounting shaft 5a about the pair of mounting shafts 5b and 5c to form the first gear 1 And a pair of mounting members 9a, 9b so as to adjust the backlash between the second gear 3 and the second gear 3.
And a pair of mounting members 9a, 9b
It is mounted so that it can be positioned with respect to. That is, the second
The shaft 5 has a pair of mounting shaft portions 5 at both ends in the axial direction.
b, 5c are holes 10a, 10 of a pair of mounting members 9a, 9b.
b is rotatably fitted to the end of the mounting shaft portion 5c protruding out of the mounting member 9b on one side, and a rotation adjusting portion 18 comprising a minus driver groove or a plus driver groove is provided. The backlash can be adjusted by fitting the tip of a flathead screwdriver or a flathead screwdriver into the portion 18 and rotating the second shaft 5. In the middle of the mounting shaft 5b opposite to the mounting shaft 5c, the mounting member 9 is provided in the same manner as in the above-described example.
A contact portion 5d, which is a stepped portion that abuts on the inner surface of the mounting member 5a, is provided with a screw hole 19 at the tip of the mounting shaft portion 5b. Screw 21 for positioning and locking via washer 20 applied to the outer surface
Is screwed. When the positioning and locking screw 21 is tightened, the force holding the mounting member 9a between the contact portion 5d and the washer 20 is increased, and the positioning and locking is performed so that the second shaft 5 does not rotate around its axis. Will be done. For this reason,
The positioning and locking means 22 of the second shaft 5 is formed by these contact portions 5d, screw holes 19, washers 20, and positioning and locking screws 21.
Is configured.

In such a structure, the tip of the driver is fitted to the rotation adjusting portion 18 of the second shaft 5 with the positioning and locking screw 21 being loosened, and the second shaft 5 is rotated. The backlash between the first gear 1 and the second gear 3 can be adjusted. That is, similarly to the first example, the gear mounting shaft 5a existing between the pair of mounting shafts 5b and 5c is eccentric with respect to the mounting shafts 5b and 5c. Since the second gear 3 is arranged concentrically on the outer periphery of the shaft portion 5a, when the second shaft 5 is rotated around the mounting shaft portions 5b and 5c, the first gear 3 is set in accordance with the rotation angle. The backlash between the gear 1 and the second gear 3 can be adjusted. When the backlash adjustment is completed in this way, the positioning and locking screw 21 is tightened to position and lock the second shaft 5 so as not to rotate.

In the second example, the rotation adjusting unit 18
Not limited to the screwdriver groove, a spanner hook may be provided at the end of the mounting shaft 5c protruding outside from the mounting member 9b, or a handle may be provided at the end of the mounting shaft 5c. You may comprise.

Further, the positioning and locking means 22 is not limited to the above example. To form a screw part, and this screw part has a washer 2
0, a nut is screwed in, and the nut 9 is tightened to clamp the mounting member 9a between the contact portion 5d and the washer 20, so that the second shaft 5 is positioned so as not to rotate around its axis. A locking structure may be used.

In the first and second examples, when a prime mover such as a motor is connected to the third shaft 7 and a load is connected to the first shaft 2, the third shaft 7 is A fourth gear 6, which is a driving shaft and is integrally attached to the driving shaft composed of the third shaft 7, is a driving gear, and a third gear 4 meshed with the driving gear composed of the fourth gear 6. Is an intermediate gear, and the second gear 3 rotating together with the intermediate gear composed of the third gear 4 is a transmission gear.
A second shaft 5 rotatably supporting an intermediate gear formed of the second gear 3 and a transmission gear formed of the second gear 3 serves as an intermediate shaft, and the first shaft meshes with the transmission gear formed of the second gear 3. The gear 1 serves as a driven gear, and the first shaft 2 on which the driven gear composed of the first gear 1 is integrally attached serves as a driven shaft.

Hereinafter, the constituent features of some of the plurality of inventions described in this specification will be described.

(I) The first gear provided at the last stage of the gear train
A first shaft provided with a first gear, a second shaft provided with a second gear meshing with the first gear, and a third gear rotated together with the second gear; 4th mesh with gear
And a third shaft provided with a third gear, wherein the second shaft has a gear mounting shaft portion to which the second and third gears are rotatably mounted, and a gear mounting shaft portion of the gear mounting shaft portion. A pair of mounting shafts respectively rotatably mounted on a pair of mounting members located on both sides, wherein the second shaft is such that the pair of mounting shafts are concentric with each other and the gear mounting is performed. The shaft is configured to be eccentric with the pair of mounting shafts,
The pair of mounting shafts of the second shaft is configured to rotate the gear mounting shaft about the pair of mounting shafts so as to rotate the gear mounting shaft between the first gear and the second gear. A gear device characterized in that the gear device is rotatably adjustable to the pair of mounting members so as to adjust backlash and is positioned so as to be positionable with respect to the pair of mounting members. (II) The gear device according to (I), wherein a rotation adjusting portion for rotating the second shaft is provided at a portion of one end of the second shaft protruding outside one of the mounting members. .

(III) At the other end of the second shaft through which the other mounting member penetrates, there is provided a positioning locking means for stopping rotation of the second shaft. 3. The gear device according to claim 1.

(IV) A driving shaft having a driving gear, an intermediate gear meshing with the driving gear, an intermediate shaft having a transmission gear rotating together with the intermediate gear, and a driven gear meshing with the transmission gear. And a driven shaft provided with the intermediate gear, the intermediate gear and the transmission gear are rotatably mounted on a gear mounting shaft portion and on both sides of the gear mounting shaft portion. A pair of mounting shafts rotatably mounted on a mounting member, wherein the intermediate shaft has the axes of the pair of mounting shafts respectively coincident with each other, and the axis of the gear mounting shaft is the pair of mounting shafts. The pair of mounting shafts are configured not to coincide with the axis of the mounting shaft, and the pair of mounting shafts are rotatable about the axis and are mounted so as to be positionable with respect to the pair of mounting members. Characteristic gear device.

(V) The gear device according to (I), wherein a rotation adjusting portion for rotating the intermediate shaft is provided at a portion of one end of the intermediate shaft protruding outside one of the mounting members.

(III) At the part of the other end of the intermediate shaft that penetrates the other mounting member, there is provided positioning locking means for stopping rotation of the intermediate shaft.
3. The gear device according to claim 1.

[0037]

According to the present invention, the backlash between the first gear (driven gear) and the second gear (intermediate gear) is always kept small by using the rotation urging force generating mechanism. In addition, the backlash can be automatically adjusted, and there is an advantage that the backlash adjustment is not troublesome.

Further, even when the rotation urging force generating mechanism is not used, the first gear (driven gear) and the second gear can be adjusted by rotating the gear mounting shaft about the pair of mounting shafts. There is an advantage that the backlash with the (intermediate gear) can be adjusted.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first example of an embodiment of a gear device according to the present invention.

FIG. 2 is a front view showing a positional relationship between each shaft and each gear of the gear device shown in FIG.

FIG. 3 is a transverse sectional view showing a second example of the embodiment of the gear device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st gear (driven gear) 2 1st shaft (driven shaft) 3 2nd gear (transmission gear) 4 3rd gear (intermediate gear) 5 2nd shaft (intermediate shaft) 5a Gear mounting shaft part 5b, 5c Mounting shaft portion 6 Fourth gear (drive side gear) 7 Third shaft (drive shaft) 8 Through hole 9a, 9b Mounting member 9 Gear box 11 Ball bearing 12 Metal bearing 13 Rotating urging force generating mechanism 14, 15 Coil spring 17 Reduction gear 18 Rotation adjustment unit

Claims (5)

[Claims] 1. A first shaft provided with a first gear provided at the last stage of a gear train, a second gear meshing with the first gear, and a third gear rotating together with the second gear. And a third shaft provided with a fourth gear meshing with the third gear, wherein the second shaft comprises the second and third gears. A gear mounting shaft portion rotatably mounted with a pair of gears, and a pair of mounting shaft portions located on both sides of the gear mounting shaft portion and rotatably mounted on a pair of mounting members, respectively. The second shaft is configured such that the pair of mounting shafts are concentric with each other and the gear mounting shaft is eccentric with the pair of mounting shafts. The first gear and the second gear The gear mounting shaft is rotated about the pair of mounting shafts in a direction for adjusting backlash between the gear and the gear. A gear device comprising: a rotation urging force generating mechanism for applying a rotation urging force to the second shaft. A driving shaft provided with a driving gear; an intermediate shaft provided with an intermediate gear meshing with the driving gear; and a transmission gear rotating together with the intermediate gear; and a driven gear meshing with the transmission gear. And a driven shaft, wherein the intermediate shaft is located on both sides of the gear mounting shaft portion on which the intermediate gear and the transmission gear are rotatably mounted, and each of the intermediate shafts has a pair of mounting shafts. A pair of mounting shafts rotatably mounted on a member, wherein the intermediate shaft has the axes of the pair of mounting shafts respectively coincident with each other, and the axis of the gear mounting shafts is the pair of mounting shafts. The gear axis is configured not to coincide with the axis of the shaft section, and the gear mounting shaft is rotated about the pair of mounting shaft sections in a direction to adjust backlash between the driven gear and the transmission gear. Rotation urging force A gear device comprising a rotation urging force generating mechanism applied to the pair of mounting shaft portions of the intermediate shaft. 3. The rotating urging force generating mechanism includes a pair of coil springs fitted to the pair of mounting shafts, and one end of each of the pair of coil springs is connected to the pair of mounting shafts. The gear device according to claim 1, wherein the gear device is fixed and the other end is fixed to the pair of attachment members. 4. A first shaft provided with a first gear provided at a last stage of a gear train, a second gear meshing with the first gear, and a third gear rotating together with the second gear. And a third shaft provided with a fourth gear meshing with the third gear, wherein the second shaft comprises the second and third gears. A gear mounting shaft portion rotatably mounted with a pair of gears, and a pair of mounting shaft portions located on both sides of the gear mounting shaft portion and rotatably mounted on a pair of mounting members, respectively. The second shaft is configured such that the pair of mounting shafts are concentric with each other and the gear mounting shaft is eccentric with the pair of mounting shafts. The pair of mountings of the second shaft A shaft for rotating the gear mounting shaft about the pair of mounting shafts, and the first gear and the second gear. A gear device, wherein the gear device is rotatably adjustable to the pair of mounting members so as to be able to adjust backlash between the gears and is positioned so as to be positionable with respect to the pair of mounting members. 5. A driving shaft including a driving gear, an intermediate gear meshing with the driving gear, an intermediate shaft including a transmission gear rotating together with the intermediate gear, and a driven gear meshing with the transmission gear. And a driven shaft, wherein the intermediate shaft is located on both sides of the gear mounting shaft portion on which the intermediate gear and the transmission gear are rotatably mounted, and each of the intermediate shafts has a pair of mounting shafts. A pair of mounting shafts rotatably mounted on a member, wherein the intermediate shaft has the axes of the pair of mounting shafts respectively coincident with each other, and the axis of the gear mounting shafts is the pair of mounting shafts. The pair of mounting shafts are configured so as not to coincide with the axis of the shaft, and the pair of mounting shafts are rotatable about the axis and are positioned so as to be positionable with respect to the pair of mounting members. Gear device.