KR102302651B1 - Flexible engagement gear device - Google Patents

Abstract

To provide a technology that can improve coaxiality between members that rotate relatively through the main bearing.
The bending gear device 100 includes a casing 10, an internal gear 6 integrated with the casing 10 and made separately from the casing 10, and an external gear meshing with the internal gear 6 ( 4), a carrier member (8) synchronized with the rotation component of the external gear (4), and a main bearing (16) disposed between the casing (10) and the carrier member (8). The casing 10 has a front circumferential surface 10a of the rolling element of the main bearing 16, and the casing 10 and the inner gear 6 have one outer periphery and the other inner periphery to be in-long-fitted, and also pressurized. In the fitting, at least the surface hardness of the casing 10 in the in-long fitting portion 48 of the casing 10 and the internal gear 6 is determined by the internal gear 6 in the in-long fitting portion 48. ) is higher than the surface hardness of

Description

Flexible engagement gear device

This application claims priority based on Japanese Patent Application No. 2016-236575 filed on December 6, 2016. The entire contents of the application are incorporated herein by reference.

The present invention relates to a bending gear device.

Patent Document 1 discloses a bending gear device (wave gear device unit) as shown in FIG. 3 .

In Fig. 3, a wave gear device unit 200 has a cup-shaped wave gear device 110 and a cross roller bearing 150 as a main bearing. The wave gear device 110 includes an annular rigid internal gear 120 having an internal tooth 123 formed on the inner circumferential surface, a cup-shaped flexible external gear 130 disposed on the inside, and the inner side A wave generator 140 is provided. The crossed roller bearing 150 connects the rigid internal gear 120 and the flexible external gear 130 in a relatively rotatable state.

When the wave generator 140 rotates, it is a relative rotation according to a dimensional difference between the flexible external gear 130 and the rigid internal gear 120 , and is greatly reduced with respect to the rotation of the wave generator 140 . Relative rotation occurs. For example, when the rigid internal gear 120 is fixed, the flexible external gear 130 rotates, and a largely reduced rotation is transmitted to the inner ring 155 of the crossed roller bearing 150 connected thereto. do.

Patent Document 1: Japanese Patent Application Laid-Open No. 2000-186718

In the conventional bending mesh gear device as described in Patent Document 1, there was room for improvement in the coaxiality between the members rotating relatively through the main bearing, and also in the rotational precision of the bending mesh gear device. If the rotational precision is improved, it is possible to further reduce the vibration and noise of the bending gear device.

The present invention has been made in view of such a situation, and an object thereof is to provide a technique capable of improving the degree of coaxiality between members rotating relatively through the main bearing.

In order to solve the above problems, the bending gear device of an aspect of the present invention includes a casing, an internal gear formed separately from the casing and integrated into the casing, an external gear engaged with the internal gear, and rotation of the external gear A bending mesh gear device comprising a carrier member synchronized with a component, and a main bearing disposed between a casing and a carrier member, wherein the casing has an outer ring side running surface of a rolling element of the main bearing. The casing and the internal gear have one outer periphery and the other inner periphery in-long fit, and are formed by an interference fit, and at least the surface hardness of the casing in the in-long fitting portion of the casing and the internal gear is It is higher than the surface hardness of the internal gear in the inlong fitting portion.

However, arbitrary combinations of the above components, and those in which the components and expressions of the present invention are mutually substituted between methods, apparatuses, systems, etc. are also effective as aspects of the present invention.

According to the present invention, it is possible to improve the coaxiality between the members rotating relatively through the main bearing.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows the bending-meshing type gear apparatus which concerns on embodiment.
FIG. 2 is an enlarged cross-sectional view showing the internal gear of FIG. 1 and its periphery.
3 is a cross-sectional view showing a conventional wave gear device unit.

Hereinafter, the same code|symbol shall be attached|subjected to the same or equivalent component, member, and process shown in each figure, and the description which overlaps suitably is abbreviate|omitted. In addition, in order to facilitate understanding, the size of the member in each figure is enlarged and reduced suitably, and is shown. In addition, in each figure, in demonstrating embodiment, a part of the member which is not important is abbreviate|omitted and displayed.

1 : is sectional drawing which shows the bending-meshing type gear apparatus 100 which concerns on embodiment. The bending gear device 100 decelerates the input rotation and outputs it. The bending gear device 100 includes a wave generator 2 , an external gear 4 , an internal gear 6 , a carrier member 8 , a casing 10 , and a first regulating member 12 . ), and a second regulating member 14 , a main bearing 16 , a first bearing housing 18 , and a second bearing housing 20 .

The wave generator 2 includes a vibrating body shaft 22, a plurality of first rolling elements 24a, a plurality of second rolling elements 24b, a first supporter 26a, and a second supporter ( 26b), a first outer ring member 28a, and a second outer ring member 28b. The vibrating body shaft 22 is an input shaft, for example, connected to rotational drive sources, such as a motor, and rotates centering around the rotation shaft R. The vibrating body shaft 22 is integrally formed with the vibrating body 22a whose cross section orthogonal to the rotation axis R is substantially elliptical shape.

The plurality of first rolling elements 24a each have a substantially cylindrical shape, and are provided at intervals in the circumferential direction in a state in which the axial direction faces a direction substantially parallel to the rotation axis R direction. The 1st rolling body 24a is supported so that rolling is possible by the 1st support machine 26a, and rolls the outer peripheral surface 22b of the vibrating body 22a. The 2nd rolling element 24b is comprised similarly to the 1st rolling element 24a. The plurality of second rolling elements 24b are supported so as to be able to roll by a second supporter 26b arranged side by side with the first supporter 26a in the axial direction, and the outer peripheral surface 22b of the vibrating element 22a. to Jeonju Hereinafter, the 1st rolling element 24a and the 2nd rolling element 24b are collectively called "rolling body 24". Moreover, the 1st supporter 26a and the 2nd supporter 26b are collectively called "supporter 26".

The first outer ring member 28a surrounds the plurality of first rolling elements 24a. The first outer ring member 28a has flexibility and is bent in an elliptical shape by the vibrating body 22a via the plurality of first rolling elements 24a. When the vibrating body 22a (that is, the vibrating body shaft 22) rotates, the 1st outer ring member 28a is continuously bent and deformed according to the shape of the vibrating body 22a. The second outer ring member 28b has the same configuration as the first outer ring member 28a. The second outer ring member 28b is formed as a separate body from the first outer ring member 28a. However, the second outer ring member 28b may be formed integrally with the first outer ring member 28a. Hereinafter, the first outer ring member 28a and the second outer ring member 28b are collectively referred to as "outer ring member 28".

The external gear 4 is an annular member having flexibility, and the vibrating body 22a, the rolling body 24, and the outer ring member 28 are fitted inside it. The external gear 4 is bent in an elliptical shape when the vibrating body 22a, the rolling body 24 and the outer ring member 28 are fitted. When the external gear 4 rotates, the vibrating body 22a is continuously bent and deformed according to the shape of the vibrating body 22a. The external gear 4 includes a first external tooth part 4a, a second external tooth part 4b, and a base material 4c. The first external teeth 4a and the second external teeth 4b are formed on a single substrate 4c and have the same dimensions.

The internal gear 6 is an annular member having rigidity. The first internal tooth part 6a of the internal gear 6 surrounds the first external tooth part 4a of the external gear 4 bent in an elliptical shape, and the first internal tooth part 6a in a predetermined area near the long axis of the vibrating body 22a is first It engages with the external tooth portion (4a). The first internal tooth portion 6a has more teeth than the first external tooth portion 4a.

The carrier member 8 is a cylindrical member having rigidity. In this embodiment, the 2nd internal tooth part 8a is formed in the inner periphery of the carrier member 8. As shown in FIG. The second inner tooth portion 8a of the carrier member 8 surrounds the second outer tooth portion 4b of the external gear 4 bent in an elliptical shape, and is a second in two regions in the long axis direction of the vibrating body 22a. It engages with the external tooth portion (4b). The second inner tooth portion 8a has the same number of teeth as the second outer tooth portion 4b. Accordingly, the carrier member 8 rotates in synchronization with the rotation of the second external tooth portion 4b and furthermore the external gear 4 .

The first regulating member 12 is a flat ring-shaped member, and is opposed to each axial end face of the external gear 4, the first outer ring member 28a, and the first supporter 26a, the external gear 4 ), the first outer ring member 28a and the first supporter 26a and the first bearing housing 18 are disposed. The second regulating member 14 is a flat ring-shaped member, and is opposed to each axial end face of the external gear 4, the second outer ring member 28b, and the second supporter 26b, the external gear 4 ), the second outer ring member 28b and the second supporter 26b and the second bearing housing 20 are disposed. The first regulating member 12 and the second regulating member 14 regulate the movement in the axial direction of the external gear 4 , the outer ring member 28 , and the supporter 26 .

The casing 10 is a substantially cylindrical member and surrounds the carrier member 8 . In the casing 10, the internal gear 6 is connected and integrated as described later. A main bearing 16 is disposed between the casing 10 and the carrier member 8 . The main bearing 16 is a crossed roller bearing in the present embodiment, and includes a plurality of rollers (rolling body) 46 provided at intervals in the circumferential direction. The plurality of rollers (46) roll the front surface (8b) of the carrier member (8) and the front surface (10a) of the casing (10). That is, the outer circumferential side of the carrier member 8 functions as an inner ring of the main bearing 16 , and the inner circumferential side of the casing 10 functions as an outer ring of the main bearing 16 . The casing 10, via the main bearing 16, supports the carrier member 8 in a relatively rotatable manner.

The first bearing housing 18 is an annular member and surrounds the vibrating body shaft 22 . Similarly, the second bearing housing 20 is an annular member and surrounds the vibrating body shaft 22 . The first bearing housing 18 and the second bearing housing 20 include an external gear 4, a rolling element 24, a supporter 26, an outer ring member 28, a first regulating member 12 and a first 2 It is arrange|positioned so that the regulating member 14 may be interposed in an axial direction. The first bearing housing 18 is inlong-fitted to the internal gear 6 . The second bearing housing (20) is inlong-fitted to the carrier member (8). A bearing 30 is mounted on the inner periphery of the first bearing housing 18 , and a bearing 32 is mounted on the inner periphery of the second bearing housing 20 , and the vibrating body shaft 22 includes a bearing 30 and a bearing Through 32, the first bearing housing 18 and the second bearing housing 20 are rotatably supported.

An oil seal 40 is disposed between the vibrating body shaft 22 and the first bearing housing 18, and an O-ring 34 is disposed between the first bearing housing 18 and the internal gear 6, An O-ring 36 is disposed between the internal gear 6 and the casing 10 , and an oil seal 42 is disposed between the casing 10 and the carrier member 8 , and the carrier member 8 and An O-ring 38 is disposed between the second bearing housing 20 , and an oil seal 44 is disposed between the second bearing housing 20 and the vibrating body shaft 22 . Thereby, it is possible to suppress leakage of the lubricant in the bending gear device 100 .

The operation of the bending mesh gear device 100 configured as described above will be described. Here, the dimension of the first external tooth part 4a is 100, the dimension of the second external tooth part 4b is 100, the dimension of the first internal tooth part 6a is 102, and the dimension of the second internal tooth part 8a is 100. A case where , is described as an example. In addition, the case where the internal gear 6 and the 1st bearing housing 18 are in a fixed state is taken as an example and demonstrated.

When the vibrating body shaft 22 rotates in a state in which the first external tooth portion 4a is engaged with the first internal tooth portion 6a at two locations in the elliptical major axis direction, the first external tooth portion 4a and the first The engagement position of the internal tooth part 6a also moves in the circumferential direction. Since the first external tooth part 4a and the first internal tooth part 6a have different dimensions, the first external tooth part 4a rotates relatively with respect to the first internal tooth part 6a at this time. Since the internal gear 6 and the 1st bearing housing 18 are in a fixed state, the 1st external tooth|tooth part 4a rotates only by the part corresponded to a dimensional difference. That is, the rotation of the vibrating body shaft 22 is greatly reduced and output to the first external tooth portion 4a. The reduction ratio is as follows.

Reduction ratio = (dimension of first external tooth part 4a - dimension of first internal tooth part 6a) / dimension of first external tooth part 4a

=(100-102)/100

=-1/50

Since the second external tooth portion 4b is integrally formed with the first external tooth portion 4a, it rotates integrally with the first external tooth portion 4a. Since the second external tooth part 4b and the second internal tooth part 8a have the same size, relative rotation does not occur, and the second external tooth part 4b and the second internal tooth part 8a rotate integrally. For this reason, the same rotation as the rotation of the 1st external tooth part 4a is output to the 2nd internal tooth part 8a. As a result, from the 2nd internal tooth part 8a, the output which reduced the rotation of the vibrating body shaft 22 to -1/50 can be taken out.

Then, the connection structure of the internal gear 6, the casing 10, and the 1st bearing housing 18 is demonstrated in detail.

2 is an enlarged cross-sectional view showing the internal gear 6 and its periphery on an enlarged scale. The internal gear 6 has an inner portion 6b in which the first inner tooth portion 6a is formed, and an outer portion 6c located radially outside the inner portion 6b. The axial end face 10c of the casing 10 abuts against the axial end face 6g of the outer portion 6c. The axial end face 6h of the inner portion 6b projects toward the carrier member 8 side (left in Fig. 2) in the axial direction than the axial end face 6g of the outer portion 6c, and the inner portion 6b ), the outer periphery 6d is fitted with the inner periphery 10b of the casing 10 . That is, the outer periphery 6d of the inner portion 6b of the internal gear 6 and the inner periphery 10b of the casing 10 are inlong-fitted. In particular, the outer periphery 6d of the inner portion 6b and the inner periphery 10b of the casing 10 are inlong-fitted by an interference fit.

In the inner portion 6b, a concave portion 6e is formed from the axial end face 6h to the opposite side to the carrier member 8 (the right side in Fig. 2). The recessed part 6e is preferably formed so that it may become an endless ring-shaped recessed part. Moreover, the recessed part 6e is formed so that the maximum depth D in an axial direction may become larger than the length H in the axial direction of the in-long fitting part 48. As shown in FIG. Moreover, the recessed part 6e is provided radially inside the in-long fitting part 48, and the recessed part 6e and the in-long fitting part 48 overlap when viewed from the radial direction.

Moreover, as for the casing 10 and the internal gear 6, at least the surface hardness of the casing 10 in the in-long fitting part 48 is that of the internal gear 6 in the in-long fitting part 48. It is formed to be higher than the surface hardness. For example, this can be realized by subjecting the surface of the casing 10 corresponding to the inlong fitting portion 48 to heat treatment such as carburizing heat treatment or induction heat treatment. In this embodiment, since the casing 10 has the circumferential surface 10a of the main bearing 16, the casing 10 is heat-treated in order to ensure the hardness as a circumferential surface. As a result, the surface hardness of the casing 10 in the inlong fitting portion 48 is also secured to be the same as that of the front peripheral surface 10a.

However, "surface hardness" refers to the hardness measured at a depth equivalent to 2.5 times the diagonal length of the groove in the Vickers hardness test by the measurement method specified in JIS G0559 when induction heat treatment is performed, for example. For example, when carburizing heat treatment is performed, it refers to the hardness measured at a depth equivalent to 2.5 times the diagonal length of the groove in the Vickers hardness test according to the measurement method specified in JIS B0557. As for the casing 10 and the internal gear 6, Preferably, the surface hardness of the casing 10 in the in-long fitting part 48 is the internal gear 6 in the in-long fitting part 48. It is formed so that the value of Vickers hardness is 50 or more than the surface hardness of .

Moreover, the inner periphery 6f of the inner side part 6b of the internal gear 6 is fitted with the outer periphery 18a of the 1st bearing housing 18. As shown in FIG. That is, the inner periphery 6f of the inner portion 6b of the internal gear 6 and the outer periphery 18a of the first bearing housing 18 are inlong-fitted. In this embodiment, in particular, the inner periphery 6f of the inner part 6b of the internal gear 6 and the outer periphery 18a of the 1st bearing housing 18 are inlong-fitted by the intermediate fit. In addition, the fastening degree of the inner gear 6 and the inlong fitting portion 50 of the first bearing housing 18 is higher than the fastening degree of the inner gear 6 and the inlong fitting portion 48 of the casing 10 . When configured to be small, the type of fitting between the internal gear 6 and the first bearing housing 18 is not relevant.

According to the bending mesh gear device 100 according to the embodiment described above, the internal gear 6 and the casing 10 are inlong-fitted. Thereby, it becomes possible to perform the alignment at the time of connecting the internal gear 6 and the casing 10 with high precision. Moreover, according to the bending-meshing type gear apparatus 100, an in-long fit is carried out by an interference fit. Thereby, it becomes difficult to generate|occur|produce misalignment compared with the case where the internal gear 6 and the casing 10 are connected by an intermediate fit or a loose fit. Further, according to the bending mesh gear device 100 , the surface hardness of the casing 10 in the in-long fitting portion 48 is higher than the surface hardness of the internal gear 6 in the in-long fitting portion 48 . constructed to rise. Thereby, it can suppress that abrasion arises at the time of in-long fitting by an interference fit. From the above, according to the bending mesh gear apparatus 100 which concerns on this embodiment, the coaxiality of the internal gear 6 and the casing 10 can be improved, As a result, the relative rotation via the main bearing 16 is carried out. The coaxiality of the internal gear 6 and the carrier member 8 is improved.

Moreover, according to the bending mesh gear apparatus 100 which concerns on embodiment, in the inner side part 6b of the internal gear 6, the recessed part 6e which is recessed in the side opposite to the carrier member 8 from the axial end face 6h. ) is formed. Preferably, the concave portion 6e is formed to have an endless ring shape. Further, preferably, the concave portion 6e is formed such that the maximum depth D in the axial direction thereof is greater than the length H of the in-long fitting portion 48 in the axial direction. Accordingly, even if an excessive force is applied to the in-long fitting portion 48 when the inner portion 6b of the inner gear 6 is fitted into the casing 10, a part of the inner portion 6b (that is, the in-long fitting portion ( 48) It is possible to suppress the deformation of the entire inner portion 6b of the casing 10 or the inner gear 6 as only the portion in the vicinity thereof is deformed. As a result, deformation of the front surface 10a of the casing 10 can be suppressed.

In addition, in the bending mesh gear device 100, since the external gear 4 from which the optimal meshing is obtained is selected while recombining the external gear 4 of different sizes, the first bearing housing 18 has many opportunities for attachment and detachment. , Therefore, it is preferable that the degree of fastening between the internal gear 6 and the first bearing housing 18 is small. On the other hand, according to the bending mesh gear device 100 according to the embodiment, the fastening degree of the internal gear 6 and the inlong fitting portion 50 of the first bearing housing 18 is the internal gear 6 and It is configured to be smaller than the fastening degree of the inlong fitting portion 48 of the casing 10 . That is, the degree of fastening between the internal gear 6 and the inlong fitting portion 50 of the first bearing housing 18 is relatively small. Thereby, assembly property is improved.

As mentioned above, the bending mesh gear apparatus which concerns on embodiment was demonstrated. This embodiment is an illustration, and it is understood by those skilled in the art that various modifications are possible for the combination of each component or each processing process, and that such a modification also exists in the scope of the present invention. A modified example is shown below.

(Modification 1)

In the embodiment, when the inner periphery 10b of the casing 10 and the outer periphery 6d of the inner gear 6 are in-long fit, that is, the in-long fitting portion 48 is provided on the radially inner side of the casing 10 . Although the case has been described, it is not limited thereto. As shown in Fig. 3, an inlong fitting portion may be provided on the radially outer side of the casing 10 (that is, a member functioning as the outer ring of the main bearing 16). That is, the outer periphery of the casing 10 and the inner periphery of the internal gear 6 may be inlong-fitted by an interference fit.

(Modification 2)

In embodiment, it has two internal teeth (1st internal tooth part 6a, 2nd internal tooth part 8a), and the external gear 4 demonstrated the flat type bending meshing type gear apparatus which is cylindrical, but this not limited The technical idea of the present embodiment is also applicable to a cup type, a hat type, and other types of bending mesh gear devices having one internal tooth.

For example, in the cup-shaped bending mesh gear device as shown in Fig. 3, the inner periphery 120a of the rigid internal gear 120 and the outer periphery 151a of the outer ring 151 corresponding to the casing are press-fitted. The surface hardness of the outer ring 151 in the in-long fitting portion 148 of the rigid inner gear 120 and the outer ring 151 is inlong-fitted, and the rigid internal gear 120 and the outer ring 151 are in-long fit (that is, The surface hardness of the outer periphery 151a may be formed to be higher than the surface hardness of the rigid internal gear 120 in the inlong fitting portion 148 (that is, the surface hardness of the inner periphery 120a). In this case, the coaxiality of the rigid internal gear 120 and the outer ring 151 can be improved, and as a result, the rigid internal gear 120 and the inner race 155 that are relatively rotated through the cross roller bearing 150, which is the main bearing. ) is improved.

Any combination of the above-described embodiments and variations is also useful as an embodiment of the present invention. The new embodiment generated by the combination has both the effects of the combined embodiment and the modified example.

4 shout gear
6 internal gear
6d outsourcing
8 carrier member
10 casing
10a Jeonju
10b next week
16 main bearing
48, 100 Bending mesh gear units

Claims (5)

A casing, an internal gear formed separately from the casing and integrated into the casing, an external gear meshing with the internal gear, a carrier member synchronized with the rotation component of the external gear, and between the casing and the carrier member As a bending mesh gear device having a main bearing disposed in the
The casing has an outer ring side running surface of the rolling element of the main bearing,
The casing and the inner gear, one outer periphery and the other inner periphery are in-long fit, and are made of an interference fit,
At least, a surface hardness of the casing in the in-long fitting portion between the casing and the internal gear is higher than a surface hardness of the internal gear in the in-long fitting portion. The method of claim 1,
The inner periphery of the casing and the outer periphery of the inner gear are inlong-fitted,
The internal gear has a flexural meshing gear device, characterized in that a recess is provided on the inner side in the radial direction of the inlong fitting portion of the casing and the internal gear. 3. The method of claim 2,
The concave portion has an endless ring shape. 4. The method according to claim 2 or 3,
Bending mesh gear device, characterized in that the axial depth of the concave portion is greater than the axial length of the inlong fitting portion of the casing and the inner gear. The method of claim 1,
Further comprising a bearing housing which is inlong-fitted to the internal gear and is equipped with a bearing supporting the vibrating body shaft for bending and deforming the external gear,
A degree of fastening of the inner gear and the inlong fitting portion of the bearing housing is smaller than that of the inner gear and the inlong fitting portion of the casing.

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