JP2021101114A - Flexible meshing type gear device - Google Patents

Abstract

To appropriately adjust play in the axial direction of a bearing.SOLUTION: A flexible meshing type gear device (1) has an exciter shaft (10) having an exciter (10A), and a first bearing (36) and a second bearing (37), which support the exciter shaft (10), an external gear (11) that is flexibly deformed by the exciter (10A), and internal gears (31G, 32G) that mesh with the external gear (11). A shim (60) for adjusting a clearance, in which the first bearing (36) and the second bearing (37) can move in the axial direction, is disposed between members connected to each other by bolts (52) among constituent members of the flexible meshing type gear device (1).SELECTED DRAWING: Figure 1

Description

The present invention relates to a flexible meshing gear device.

Conventionally, a flexural meshing gear device including an external tooth gear that flexes and deforms is known (see, for example, Patent Document 1). The external tooth gear is flexed and deformed when the exciter shaft is internally fitted via the exciter bearing and the exciter shaft rotates inward. The exciter shaft is supported by the bearing housing via a bearing such as a ball bearing.

In such a flexible meshing gear device, it is necessary to adjust the gap (play) in which the bearing can move in the axial direction so that the bearing supporting the exciting body shaft is in an appropriate shaft supporting state. ..

Japanese Unexamined Patent Publication No. 2011-112214

The present invention has been made in view of the above circumstances, and an object of the present invention is to suitably adjust the play in the axial direction of the bearing.

The flexible meshing type gear device according to the present invention includes a oscillating body shaft having a oscillating body, first bearings and second bearings that support the oscillating body shaft, and an outer side that is flexed and deformed by the oscillating body. A flexible meshing gear device including a tooth gear and an internal gear that meshes with the external gear.
The first bearing and the second bearing have shims for adjusting the clearance that can be moved in the axial direction.
The shims are configured to be arranged between the members connected to each other by the connecting members among the constituent members of the present bending meshing type gear device.

According to the present invention, the axial play of the bearing can be suitably adjusted.

It is sectional drawing which shows the bending mesh type gear device which concerns on this embodiment. It is a figure for demonstrating the function of a shim. It is sectional drawing which shows the deformation example of the position of a shim. It is sectional drawing which shows the conventional bending mesh type gear apparatus.

For example, as shown in FIG. 4, an adjusting shim may be arranged between the outer ring of one bearing and the bearing housing. However, the outer ring of the bearing and the bearing housing may rotate relative to each other during operation. In that case, the shims arranged between them are rubbed from both sides while receiving the thrust force from the outer ring, and are deformed or damaged. As a result, the outer ring may be restrained by the deformed shim and the rotation of the bearing may be hindered, or the bearing may bite the wear powder of the shim.
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Structure of flexible meshing gear device]
FIG. 1 is a cross-sectional view showing a flexure meshing gear device 1 according to the present invention.
As shown in this figure, the flexible meshing gear device 1 is a tubular flexible meshing gear device, and is a vibration exciting body shaft 10, an external gear 11, a first internal gear 31G, and a second internal tooth. A gear 32G, a oscillating body bearing 12, a casing 33, a first bearing housing 34, and a second bearing housing 35 are provided.

The exciter shaft 10 is a hollow tubular shaft that rotates around a rotation shaft O1, and has a non-circular (for example, elliptical) outer shape of a cross section perpendicular to the rotation shaft O1 and a vibrating body 10A. It has shaft portions 10B and 10C provided on both sides in the axial direction of 10A. The ellipse is not limited to a geometrically exact ellipse and includes a substantially ellipse. The shaft portions 10B and 10C are shafts having a circular outer shape in a cross section perpendicular to the rotation shaft O1.
In the following description, the direction along the rotation axis O1 is referred to as "axial direction", the direction perpendicular to the rotation axis O1 is referred to as "diametrical direction", and the rotation direction centered on the rotation axis O1 is referred to as "circumferential direction". Further, in the axial direction, the side (left side in the figure) that outputs the decelerated motion connected to the external driven member E to the driven member E is called the "output side", which is opposite to the output side. The side (right side in the figure) is called the "anti-output side".

The external gear 11 is a cylindrical member having flexibility and centered on the rotating shaft O1, and is provided with teeth on the outer periphery.

The first internal gear 31G and the second internal gear 32G rotate around the exciter shaft 10 about the rotation shaft O1. The first internal gear 31G and the second internal gear 32G are provided side by side in the axial direction and mesh with the external gear 11. Specifically, one of the first internal gear 31G and the second internal gear 32G meshes with the tooth portion on one side of the center of the external gear 11 in the axial direction, and the other meshes with the tooth portion on one side from the center in the axial direction of the external gear 11. It meshes with the tooth on the other side of the center.
Of these, the first internal gear 31G is configured by providing internal teeth at the corresponding portion of the inner peripheral portion of the first internal gear member 31. On the other hand, the second internal gear 32G is configured by providing internal teeth at a corresponding portion of the inner peripheral portion of the second internal gear member 32.

The oscillating body bearing 12 is, for example, a roller bearing, and is arranged between the oscillating body 10A and the external gear 11. The exciter 10A and the external gear 11 can rotate relative to each other via the exciter bearing 12.
The oscillating body bearing 12 has an outer ring 12a fitted inside the external gear 11, a plurality of rolling elements (rollers) 12b, and a cage 12c for holding the plurality of rolling elements 12b.
The plurality of rolling elements 12b are arranged in the radial direction of the first internal gear 31G, and are arranged in the radial direction of the first group of rolling elements 12b arranged in the circumferential direction and the second internal gear 32G. It has a second group of rolling elements 12b arranged in the circumferential direction. These rolling elements 12b roll with the outer peripheral surface of the oscillator 10A and the inner peripheral surface of the outer ring 12a as rolling surfaces. Two outer rings 12a having the same shape are provided side by side in the axial direction corresponding to the arrangement of the plurality of rolling elements 12b. The oscillating body bearing 12 may have an inner ring that is separate from the oscillating body 10A.

Spacer rings 41 and 42 are provided on both sides of the oscillating body bearing 12 and the external gear 11 in the axial direction as regulatory members that abut against them and regulate their axial movement.

The casing 33 is connected to the first internal gear member 31 and covers the outer diameter side of the second internal gear 32G. The casing 33 has an outer ring portion of a main bearing 38 (for example, a cross roller bearing) formed on the inner peripheral portion, and rotatably supports the second internal gear member 32 via the main bearing 38. There is.
The casing 33 and the first internal gear member 31 are provided with connecting holes 33h and 31h extending continuously in the axial direction. When the flexible meshing gear device 1 is connected to an external mating device (driven device), the casing 33 and the first internal gear member 31 are connected to the mating device (driven member E) via the connecting holes 33h and 31h. It is connected to a fixing member different from the above) by co-tightening. The connecting holes 33h and 31h are provided at a plurality of locations in the circumferential direction.
Further, the casing 33 and the first internal gear member 31 have different bolt holes 33j and 31j whose positions in the circumferential direction are different from those of the connecting holes 33h and 31h, and are inserted into the bolt holes 33j and 31j. They are connected to each other by screwed bolts 51 (connecting members). That is, the bolt 51 is attached to the flexible meshing gear device 1 in a state before the flexible meshing gear device 1 is attached to the driven member E.

The first bearing housing 34 is connected to the first internal gear member 31 and covers the meshing portion between the external gear 11 and the first internal gear 31G from the opposite output side in the axial direction. The first bearing housing 34 supports a first bearing 36 (for example, a ball bearing) arranged between the exciting body shaft 10 and the shaft portion 10B. That is, the first bearing housing 34 rotatably supports the exciter shaft 10 via the first bearing 36.
The first bearing housing 34 and the first internal gear member 31 have bolt holes 34k and 31k provided at a plurality of locations in the circumferential direction, and bolts inserted and screwed into the bolt holes 34k and 31k. They are connected to each other by 52 (connecting member). That is, the bolt 52 is attached to the flexible meshing gear device 1 in a state before the flexible meshing gear device 1 is attached to the driven member E.
Further, a shim 60, which will be described later, is arranged between the first bearing housing 34 and the first internal gear member 31.

The second bearing housing 35 is connected to the second internal gear member 32 and covers the meshing portion between the external gear 11 and the second internal gear 32G from the output side in the axial direction. The second bearing housing 35 supports a second bearing 37 (for example, a ball bearing) arranged between the exciting body shaft 10 and the shaft portion 10C. That is, the second bearing housing 35 rotatably supports the exciter shaft 10 via the second bearing 37.
The second bearing housing 35 and the second internal gear member 32 are provided with bolt connecting holes 35h and 32h extending continuously in the axial direction at the end on the output side. When the flexible meshing gear device 1 is connected to an external mating device, the second bearing housing 35 and the second internal gear member 32 are connected to the driven member E of the mating device via the bolt connecting holes 35h and 32h. It is connected by tightening together. Bolt connecting holes 35h and 32h are provided at a plurality of locations in the circumferential direction.
Further, the second bearing housing 35 and the second internal gear member 32 have different bolt holes 35j and 32j whose positions are different from those of the bolt connecting holes 35h and 32h in the circumferential direction. They are connected to each other by bolts 53 (connecting members) inserted and screwed into 32j. That is, the bolt 53 is attached to the flexible meshing gear device 1 in a state before the flexible meshing gear device 1 is attached to the driven member E.

Further, the flexible meshing gear device 1 includes oil seals 43, 44, 45 for sealing and O-rings 46, 47, 48.
The oil seal 43 is arranged between the shaft portion 10B of the exciter shaft 10 and the first bearing housing 34 at the end portion on the counter-output side in the axial direction, and suppresses the outflow of the lubricant to the counter-output side. .. The oil seal 44 is arranged at the end on the output side in the axial direction between the shaft portion 10C of the exciter shaft 10 and the second bearing housing 35, and suppresses the outflow of the lubricant to the output side. The oil seal 45 is arranged between the casing 33 and the second internal gear member 32, and suppresses the outflow of the lubricant from this portion.
The O-rings 46, 47, 48 are provided between the first internal gear member 31 and the first bearing housing 34, between the first internal gear member 31 and the casing 33, and between the second internal gear member 32 and the second bearing housing 34. It is provided between the bearing housing 35 and the bearing housing 35 to prevent the lubricant from moving between them.

[Adjustment shim]
A shim 60 is arranged between the first bearing housing 34 and the first internal gear member 31 to adjust the gap (size) in which the first bearing 36 and the second bearing 37 can move in the axial direction. ing. The first bearing housing 34 and the first internal gear member 31 have contact surfaces 34f and 31f that are in contact with each other in the axial direction and define their axial positions, and the contact surfaces 34f and 31f are shims. They are in contact with each other via 60.
The shim 60 is made of, for example, stainless steel or cold-rolled steel, and is formed in a ring shape corresponding to the contact surfaces 34f and 31f. Further, a plurality of bolts 52 connecting the first internal gear member 31 and the first bearing housing 34 are inserted through the contact surfaces 34f and 31f, and the shim 60 is positioned in the circumferential direction corresponding to the plurality of bolts 52. It has a hole 60a for escaping the bolt 52. Therefore, the shim 60 is prevented from moving relative to the first internal gear member 31 and the first bearing housing 34 by the bolts 52 arranged between the first internal gear member 31 and the first bearing housing 34. Is fixed to.

As described above, the shim 60 adjusts a gap (hereinafter, also referred to as “axial play”) in which the first bearing 36 and the second bearing 37 can move in the axial direction. More specifically, as shown in FIG. 2, the shim 60 adjusts the inter-bearing distance L1 between the first bearing 36 and the second bearing 37 on the housing side supporting the exciter shaft 10.
The bearing-to-bearing distance L1 on the housing side is from the stepped portion 34s of the first bearing housing 34 that abuts in the axial direction with the outer ring 36a of the first bearing 36 and defines the axial position on the counter-output side of the first bearing 36. This is the distance from the stepped portion 35s of the second bearing housing 35 that comes into contact with the outer ring 37a of the second bearing 37 in the axial direction and defines the axial position of the second bearing 37 on the output side.

In the present embodiment, when there is no shim 60 at the time of design (when the contact surfaces 34f and 31f of the first bearing housing 34 and the first internal gear member 31 are in direct contact with each other), the play in the axial direction is negative. The dimensions of each part are designed so as to be. Then, at the time of assembly, the thickness t of the shim 60 is determined while measuring the axial distance of each part so that the play in the axial direction becomes a predetermined size (for example, 0.05 mm).
As a result, the size of the gap (axial play) in which the first bearing 36 and the second bearing 37 can move in the axial direction can be appropriately set, and the first bearing 36 and the second bearing 37 are in a suitable shaft support state. Can be.

The position of the shim 60 is not limited to the position between the first bearing housing 34 and the first internal gear member 31. It suffices if the size of the gap (axial play) in which the first bearing 36 and the second bearing 37 can move in the axial direction can be adjusted, and the shim 60 is a bolt (a member of the flexible meshing gear device 1). It suffices if it is arranged between the members connected to each other by the connecting member).
For example, as shown in FIG. 3A, the shim 60 may be arranged between the casing 33 and the first internal gear member 31. Specifically, of the casing 33 and the first internal gear member 31, the contact surfaces 33e and 31e that abut in the axial direction and define the axial positions of each other may be brought into contact with each other via the shim 60. Good. In this case, the hole 60a of the shim 60 is inserted into the connecting holes 33h and 31h in addition to the bolt 51 (see FIG. 1) that connects the casing 33 and the first internal gear member 31, and the flexible meshing gear device 1 It is provided at a position corresponding to these bolts 51 and the connecting member so that a connecting member (not shown) that connects the other device and the mating device can also escape.
Alternatively, as shown in FIG. 3B, the shim 60 may be arranged between the second bearing housing 35 and the second internal gear member 32. Specifically, of the second bearing housing 35 and the second internal gear member 32, the contact surfaces 35e and 32e that are in contact with each other in the axial direction and define the axial positions of each other are brought into contact with each other via the shim 60. You may let me. In this case, the hole 60a of the shim 60 is inserted into the bolt connecting holes 35h and 32h in addition to the bolt 53 (see FIG. 1) that connects the second bearing housing 35 and the second internal gear member 32, and is flexed and meshed. A connecting member (not shown) that connects the type gear device 1 and the driven member E of the mating device is also provided at a position corresponding to these bolts 53 and the connecting member so that they can escape.
However, in the examples of FIGS. 3A and 3B, unlike the case where the shim 60 is arranged between the first bearing housing 34 and the first internal gear member 31, the shim 60 is a flexible meshing gear device 1. After the flexible meshing gear device 1 is assembled, a connecting member for connecting to the mating device is connected to both members sandwiching the shim 60. Therefore, for example, the shim 60 may be deformed because the connecting member connected to the mating device (driven member E) is fastened with an excessive tightening torque. In this regard, when the shim 60 is arranged between the first bearing housing 34 and the first internal gear member 31, the state in which the bolt 52 is fastened with an appropriate tightening torque that does not deform the shim 60 is maintained. , There is no risk of such deformation of the shim 60.

[Deceleration operation of flexible meshing gear device]
Subsequently, the deceleration operation of the flexure meshing gear device 1 will be described.
When the exciter shaft 10 is rotationally driven by a drive source such as a motor, the motion of the exciter 10A is transmitted to the external gear 11. At this time, the external gear 11 is restricted to a shape along the outer peripheral surface of the exciter 10A, and is bent into an elliptical shape having a long axis portion and a short axis portion when viewed from the axial direction. Further, the external gear 11 meshes with the fixed first internal gear 31G at a long shaft portion. Therefore, the external gear 11 does not rotate at the same rotation speed as the exciting body 10A, and the exciting body 10A rotates relatively inside the external gear 11. Then, with this relative rotation, the external gear 11 bends and deforms so that the major axis position and the minor axis position move in the circumferential direction. The period of this deformation is proportional to the rotation period of the exciter shaft 10.

When the external gear 11 bends and deforms, its long axis position moves, so that the meshing position between the external gear 11 and the first internal gear 31G changes in the rotational direction. Here, for example, assuming that the number of teeth of the external gear 11 is 100 and the number of teeth of the first internal gear 31G is 102, the external gear 11 and the first internal gear 31G are engaged every time the meshing position goes around. The meshing teeth of the teeth are displaced, which causes the external gear 11 to rotate (rotate). With the above number of teeth, the rotational motion of the exciter shaft 10 is decelerated at a reduction ratio of 100: 2 and transmitted to the external gear 11.

On the other hand, since the external gear 11 also meshes with the second internal gear 32G, the meshing position between the external gear 11 and the second internal gear 32G also changes in the rotation direction due to the rotation of the exciter shaft 10. .. Here, assuming that the number of teeth of the second internal gear 32G and the number of teeth of the external gear 11 are the same, the external gear 11 and the second internal gear 32G do not rotate relatively, and the external teeth The rotational movement of the gear 11 is transmitted to the second internal gear 32G with a reduction ratio of 1: 1. As a result, the rotational motion of the exciter shaft 10 is decelerated at a reduction ratio of 100: 2 and transmitted to the second internal gear member 32 and the second bearing housing 35, and this rotational motion is output to the driven member E. Tooth.

Here, in the flexible meshing type gear device 1, the shims 60 for adjusting the axial play of the first bearing 36 and the second bearing 37 are connected to each other by bolts 52, and the first bearing housing 34 and the first internal tooth are connected to each other. It is arranged between the gear members 31. Therefore, unlike the case where the shim is arranged between the outer ring of the bearing and the bearing housing (see FIG. 4), the shim 60 and the first bearing housing 34 and the first internal gear member 31 rotate relative to each other when the device is operated. There is no. As a result, deformation and damage of the shim 60 due to rubbing can be suppressed, and a suitable shaft support state of the first bearing 36 and the second bearing 37 can be maintained by adjustment with the shim 60.

[Technical effect of this embodiment]
As described above, according to the present embodiment, the shim 60 for adjusting the axial play between the first bearing 36 and the second bearing 37 that support the exciter shaft 10 is a flexible meshing gear device 1. Of the constituent members of the above, the members are arranged between the members connected to each other by the bolts 52.
Therefore, unlike the case where the shim is arranged between the outer ring of the bearing and the bearing housing, the shim 60, the first bearing housing 34, and the first internal gear member 31 do not rotate relative to each other when the device is operated. As a result, deformation and damage of the shim 60 due to rubbing can be suppressed, and a suitable shaft support state of the first bearing 36 and the second bearing 37 can be maintained by adjustment with the shim 60.
Therefore, the play in the axial direction of the first bearing 36 and the second bearing 37 can be suitably adjusted.

Further, according to the present embodiment, the bolt 52 (connecting member) is attached to the flexible meshing gear device 1 in a state before the flexible meshing gear device 1 is attached to the driven member E.
Therefore, the shim 60 is not co-tightened by the connecting member used for mounting on the driven member E, and the shim 60 is flexed and properly assembled in the meshing gear device 1 before mounting on the driven member E. Can be kept.

[Other]
Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.
For example, in the above embodiment, the connecting member that connects the two members that sandwich the shim 60 is a bolt. However, the connecting member is not limited to a bolt as long as the two members and the shim are fixed so as not to move relative to each other.

Further, in the above embodiment, the driven member E of the mating device is connected to the second bearing housing 35 and the second internal gear member 32, and the fixing members of the mating device different from the driven member E are the casing 33 and the second. 1 It was decided to be connected to the internal gear member 31. However, even if the driven member E of the mating device is connected to the casing 33 and the first internal gear member 31, the fixing member of the mating device is connected to the second bearing housing 35 and the second internal gear member 32. Good.

Further, in the above-described embodiment, a cylindrical meshing gear device has been described as an example of the flexible meshing gear device 1. However, the present invention can be suitably applied to a flexible meshing type gear device other than the tubular type, for example, a cup type or a top hat type.
For example, in the case of the cup type described in Japanese Patent Application Laid-Open No. 2014-74451, the cross roller bearing 12 is connected between the cylindrical casing 2 connected by the fastening bolt 11 and the end plate 3, or is connected by the fastening bolt 13. A shim may be arranged between the outer ring 12a of the above and the cylindrical casing 2.
In addition, the details shown in the above-described embodiment can be appropriately changed without departing from the spirit of the invention.

1 Flexible meshing gear device 10 Expulsion body shaft 10s Stepped portion 11 External gear 31 First internal gear member 31G First internal gear 31e Contact surface 31f Contact surface 31j Bolt hole 31k Bolt hole 32 Second Internal gear member 32G Second internal gear 32e Contact surface 32j Bolt hole 33 Casing 33e Contact surface 33j Bolt hole 34 First bearing housing 34f Contact surface 34k Bolt hole 34s Stepped portion 35 Second bearing housing 35e Contact Surface 35j Bolt hole 35s Stepped portion 36 First bearing 36a Outer ring 36b Inner ring 37 Second bearing 37a Outer ring 37b Inner ring 51 Bolt (connecting member)
52 bolts (connecting members)
53 bolts (connecting members)
60 shim 60a Hole E Driven member L1 Distance between bearings (on the housing side) O1 Rotating shaft

Claims (5)

The exciter shaft having the exciter, the first bearing and the second bearing supporting the exciter shaft, the external gear that is flexed and deformed by the exciter, and the inside that meshes with the external gear. A flexible meshing gear device including a tooth gear.
The first bearing and the second bearing have shims for adjusting the clearance that can be moved in the axial direction.
The shims are arranged between the constituent members of the flexible meshing gear device that are connected to each other by the connecting members.
Flexible meshing gear device. The connecting member is attached to the flexible meshing gear device in a state before the flexible meshing gear device is attached to the driven member.
The flexible meshing gear device according to claim 1. The connecting member connects the internal gear and the first bearing housing that supports the first bearing.
The flexible meshing gear device according to claim 1 or 2. A tubular flexible meshing gear device having a first internal gear and a second internal gear as the internal gear.
The decelerated rotation is output from the second internal gear to the driven member, and the decelerated rotation is output to the driven member.
The connecting member connects the first internal gear and the first bearing housing.
The flexible meshing gear device according to claim 3. The shim is formed in a ring shape and has holes at positions corresponding to a plurality of connecting members.
The flexible meshing gear device according to any one of claims 1 to 4.

Images