Series of bending meshing type gear devices

Abstract

To share gear parts in a plurality of flexible meshing type gear devices having different shaft lengths.SOLUTION: In a series of bending meshing type gear devices including a first bending meshing type gear device 10 and a second bending meshing type gear device 20, each of the first bending meshing type gear device 10 and the second bending meshing type gear device 20 has a gear component and a main bearing 17. At least one part of gear parts is common to the first bending meshing type gear device 10 and the second bending meshing type gear device 20. In the second bending meshing type gear device 20, the distance in the axial direction between the gear component and the main bearing 17 is longer than that of the first bending meshing type gear device 10 by a predetermined distance difference, and the gear component and the main bearing 17 are connected via a connection member that fills the distance difference.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a series of flexible mesh gearing. [Background technology]

[0002] In flexible mesh gear devices, there are cases where devices with the same outer diameter but different axial lengths are required depending on the installation location, application, etc. In order to suitably provide a device with an axial length that suits the required specifications, it is necessary to have a lineup of multiple devices with different axial lengths. However, in such cases, it becomes necessary to prepare multiple components that make up these multiple devices according to the axial lengths. In this regard, Patent Document 1 proposes a technique for standardizing a bearing device for a plurality of devices having different shaft lengths. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-10593 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technology described in Patent Document 1 does not allow for standardization of gear components, which are expensive to manufacture. The present invention has been made in view of the above circumstances, and has as its object to standardize gear components among a plurality of flexible mesh gear devices having different axial lengths. [Means for solving the problem]

[0005] The present invention provides a series of flexible mesh gear trains including a first flexible mesh gear train and a second flexible mesh gear train, each of the first flexible mesh gear set and the second flexible mesh gear set includes a gear component and a main bearing; At least one of the gear components is common between the first flexible mesh gear device and the second flexible mesh gear device, The second flexible mesh gear device is an axial distance between the gear component and the main bearing is longer than that of the first flexible mesh gear device by a predetermined distance difference; The gear component and the main bearing are connected via a connecting member that fills the distance difference. [Effects of the Invention]

[0006] According to the present invention, gear components can be standardized among a plurality of flexible mesh gear devices having different axial lengths. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a cross-sectional view showing a first flexible mesh gear device according to an embodiment. [Figure 2] FIG. 4 is a cross-sectional view showing a second flexible mesh gear device according to an embodiment. [Figure 3] FIG. 10 is a cross-sectional view showing a third flexible mesh gear device according to an embodiment. [Figure 4] FIG. 10 is a cross-sectional view showing a fourth flexible mesh gear device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0009] The series of flexible mesh gear units according to this embodiment is a product group of flexible mesh gear units including a first flexible mesh gear unit and a second flexible mesh gear unit. The first flexible mesh gear device and the second flexible mesh gear device are both cup-type flexible mesh gear devices, and have different axial lengths (lengths in the axial direction). In the following description, the "N"th flexible mesh gearings will be identified by numbers in the "Nx10" series. In the following description, the direction along the rotation axis Ax of the flexible mesh gear device is referred to as the "axial direction," the direction perpendicular to the rotation axis Ax is referred to as the "radial direction," and the direction of rotation about the rotation axis Ax is referred to as the "circumferential direction." In addition, in the axial direction, the side where the vibration exciter 11 described below is located (the right side in the drawing) is referred to as the "input side," and the side opposite the input side (the left side in the drawing) is referred to as the "anti-input side."

[0010] [Configuration of the first flexible mesh gear device] FIG. 1 is a cross-sectional view showing a first flexible mesh gear device 10. As shown in FIG. As shown in this figure, the first flexible mesh gear device 10 includes a vibrator 11 , an external gear 12 , an internal gear 13 , a vibrator bearing 14 , an output member 15 , a housing 16 , and a main bearing 17 .

[0011] The vibrator 11 is formed in the shape of a hollow short disk, and the outer shape (periphery) of a cross section perpendicular to the rotation axis Ax is elliptical (with a major axis and a minor axis that are perpendicular to each other). Note that the elliptical shape is not limited to a geometrically strict ellipse, but also includes an approximate ellipse. The vibrator 11 is connected to a drive source (not shown) such as a motor, and a driving force is input thereto.

[0012] The external gear 12 is formed in a cup shape that opens to the input side as a whole. Specifically, the external gear 12 has a cylindrical portion 12a, external teeth 12b formed on the outer peripheral surface of the input side end of the cylindrical portion 12a, and a boss portion 12c provided on the inner peripheral portion of the non-input side end of the cylindrical portion 12a. Of these, at least the cylindrical portion 12a and the external teeth 12b are flexible. A vibrator bearing 14 (for example, a ball bearing) is fitted inside the inner diameter side of the external teeth 12b, and the vibrator 11 is disposed via the vibrator bearing 14. Therefore, the external teeth 12b are flexibly deformed as the vibrator 11 rotates. The external gear 12 is an example of a gear component according to the present invention.

[0013] The internal gear 13 is formed in a substantially circular plate shape and has internal teeth 13a formed on its inner circumferential surface. The internal gear 13 is disposed on the outer diameter side of the external gear 12, and the internal teeth 13a can mesh with the external teeth 12b of the external gear 12. More specifically, the internal teeth 13a mesh with the external teeth 12b at the major axis position of the elliptical shape that has been deflected and deformed by the vibrator 11. The internal gear 13 is an example of a gear component according to the present invention.

[0014] The output member 15 is formed in a substantially annular plate shape, is disposed on the opposite input side of the external gear 12, and is fixed to a boss portion 12c of the external gear 12. A driven member (not shown) is fixed to an end face 15a on the opposite input side of the output member 15, and reduced rotation is output to the driven member. In other words, the end face 15a is the attachment position of the output member 15. An opening is formed in the center of the output member 15, and this opening is sealed by a seal cap 15b.

[0015] The housing 16 is disposed on the outer diameter side of the output member 15 and rotatably supports the output member 15 via a main bearing 17 (e.g., a ball bearing). The housing 16 is disposed on the opposite input side of the internal gear 13, and a flange portion 16a formed on the input side is fixed to the internal gear 13. An end face 16b on the opposite input side of the flange portion 16a is a mating position, and this end face 16b is fixed to an external support member. Note that instead of the end face 16b of the housing 16, the outer peripheral end face 13b of the internal gear 13 may be the mating position. The outer diameter dimension of the housing 16 or the internal gear 13 is set as the representative outer diameter dimension of the first flexible mesh gear device 10. The gap between the housing 16 and the output member 15 is sealed by an oil seal 16c. The main bearing 17 is disposed between the output member 15 and the housing 16. In the present embodiment, the main bearing 17 has an inner ring that is integrated with the output member 15 and an outer ring that is separate from the housing 16. However, the main bearing 17 may or may not have a dedicated inner ring or outer ring. Furthermore, the main bearing 17 is not limited to a ball bearing, and may be, for example, a cross roller bearing or the like. The housing 16 is an example of a connecting component according to the present invention.

[0016] In the first flexible mesh gear device 10 having the above configuration, when the vibrator 11 is driven to rotate by a drive source such as a motor, the movement of the vibrator 11 is transmitted to the external gear 12 via the vibrator bearing 14. At this time, the external gear 12 is restricted to a shape that follows the outer circumferential surface of the vibrator 11, and is bent into an elliptical shape having a major axis portion and a minor axis portion when viewed from the axial direction. Because the external gear 12 is meshed with the fixed internal gear 13 at the major axis position of the vibrator 11, it does not rotate at the same speed as the vibrator 11, and the major axis position of the vibrator 11 moves due to the flexible deformation. For example, if the number of teeth of the external gear 12 (external teeth 12b) is 100 and the number of teeth of the internal gear 13 (internal teeth 13a) is 102, each time the meshing position makes one revolution, the external gear 12 rotates (spins) by an amount equal to the difference in the number of teeth with the internal gear 13. With the above number of teeth, the rotational motion of the vibration exciter 11 is decelerated at a reduction ratio of 100:2 and transmitted to the external gear 12. This rotational motion is transmitted from the external gear 12 to the output member 15 and output to the driven member.

[0017] [Configuration of the second flexible mesh gear device] FIG. 2 is a cross-sectional view showing the second flexible mesh gear device 20. The second flexible mesh gear device 20 has the same external dimensions as the first flexible mesh gear device 10, but a longer axial length (length in the axial direction). Specifically, the distance between the mating position of the housing (or internal gear) and the mating position of the output member is longer than that of the first flexible mesh gear device 10. In other words, the axial distance between the gear component and the main bearing is longer than that of the first flexible mesh gear device 10 by a predetermined distance difference. Specifically, the second flexural mesh gear device 20 has an external gear and a housing that are different from those of the first flexural mesh gear device 10, but the other components are common to the first flexural mesh gear device 10. Components of the second flexural mesh gear device 20 that are common to the first flexural mesh gear device 10 are denoted by the same reference numerals and descriptions thereof will be omitted.

[0018] As shown in FIG. 2, the second flexible mesh gear device 20 includes an external gear 22 and a housing 26 instead of the external gear 12 and the housing 16 of the first flexible mesh gear device 10 . The external gear 22 has a cylindrical portion 22a that is formed to be longer in the axial direction than the cylindrical portion 12a of the external gear 12 of the first flexural mesh gear device 10. Other components of the external gear 22 are configured in the same way as those of the first flexural mesh gear device 10. The housing 26 is formed to be longer in the axial direction than the housing 26 of the first flexural mesh gear device 10. More specifically, a flange portion 26a formed on the input side of the housing 26 is configured similarly to the flange portion 16a of the first flexural mesh gear device 10, and the cylindrical portion other than the flange portion 26a is formed to be longer in the axial direction.

[0019] That is, in the second flexure mesh gear device 20, the axial distance between the gear component and the main bearing 17 is longer by a predetermined distance difference than in the first flexure mesh gear device 10. The distance difference is filled by the housing 26 that connects the internal gear 13 and the output member 15 (main bearing 17). This allows the output member 15 including the main bearing 17 and the internal gear 13, which is a gear component, to be shared with the first flexible mesh gear device 10. The dimensional design of the internal gear 13, which is a gear component, can be shared and manufactured using the same process. Gear components that include tooth machining require a large number of machining steps, so if the machining content changes, it takes a lot of time to modify the cutter setup and machining program used to machine the teeth. Even if the tooth machining width remains the same but the position changes, the machining setup changes. Measuring the accuracy of the teeth after machining also requires a large number of steps. In other words, gear components often require a large number of machining steps compared to other parts. Therefore, by sharing gear components, it is possible to suppress these increases in labor costs, which means lower manufacturing costs. The internal gear 13 of the first flexible mesh gear device 10 and the internal gear of the second flexible mesh gear device 20 can be manufactured using the same process.

[0020] [Modification 1 (Third flexible mesh gear device)] In the second flexible mesh gear device 20, the increased axial length compared to the first flexible mesh gear device 10 is compensated for by the external gear and the housing. However, in the flexible mesh gear device according to the present invention, when the axial distance between the gear component and the main bearing becomes longer by a predetermined distance compared to the first flexible mesh gear device 10, the difference in distance can be filled by a connecting member that connects the gear component and the main bearing. In the second flexible mesh gear device 20, the common gear component is the internal gear 13 and the housing 26 is the connecting member, but the common gear component is not limited to the internal gear, and the connecting member is not limited to the housing 26. In other words, the series of flexible mesh gear devices according to this embodiment may include a third flexible mesh gear device in which the external gear and the output member (main bearing) described below are connected by a connecting member.

[0021] FIG. 3 is a cross-sectional view showing a third flexible mesh gear device 30. As shown in this figure, the third flexible mesh gear device 30, like the second flexible mesh gear device 20, has the same external dimensions as the first flexible mesh gear device 10 but a longer axial length (length in the axial direction). However, unlike the second flexure mesh gear device 20, the third flexure mesh gear device 30 couples (connects) the external gear 12 and the output member 15 via a spacer member 38. The spacer member 38 is an example of a connecting member according to the present invention, and is formed in a cylindrical shape and fastened to the output member 15 and the boss portion 12c of the external gear 12.

[0022] That is, in the third flexible mesh gear device 30, the difference in axial length between the first flexible mesh gear device 10 and the third flexible mesh gear device 30 is compensated for by the housing and spacer member, which are connecting members. This allows the external gear 12 as well as the output member 15 and the internal gear 13 to be common to the first flexible mesh gear device 10. This in turn allows for a further reduction in the number of processing steps. When the external gear and the output member are directly fastened together, they may slip circumferentially within the range of the backlash of the fastening bolts. When the spacer member 38 is disposed between the external gear and the output member as in this embodiment, the circumferential slip can be suppressed by using a spacer member 38 with a high coefficient of friction on both end faces (contact surfaces). The coefficient of friction of the end faces can be adjusted to a desired surface roughness by, for example, processing. The spacer member 38 may also be designed to prioritize weight reduction over strength reduction. For example, the spacer member 38 may be made of a material with a lower specific gravity than the output member 15. For example, the output member may be made of an iron-based material, while the spacer may be made of aluminum or resin. The spacer member 38 may also be made of a material with a lower specific gravity than the external gear 12. For example, the external gear 12 may be made of an iron-based material, while the spacer may be made of aluminum or resin.

[0023] [Modification 2 (fourth flexible mesh gear device)] In the third flexible mesh gear device 30, the increased axial length compared to the first flexible mesh gear device 10 is compensated for by the housing and spacer member, which are connecting members. This allows the external gear 12 and the internal gear 13 to use the same gear components. However, the flexible mesh gear device according to the present invention only needs to make up for the extension in axial length with a connecting member (at least one of a housing and a spacer member) and make at least one of the external gear 12 and the internal gear 13 common. In other words, the series of flexible mesh gear trains according to this embodiment may include a fourth flexible mesh gear train in which the internal gear and the housing of the third flexible mesh gear train 30 are integrated together.

[0024] FIG. 4 is a cross-sectional view showing a fourth flexible mesh gear device 40. As shown in this figure, the fourth flexible mesh gear device 40, like the second flexible mesh gear device 20 and the third flexible mesh gear device 30, has the same external dimensions as the first flexible mesh gear device 10 but a longer axial length (length in the axial direction). However, the fourth flexible mesh gear device 40 has an internal gear 43 instead of the internal gear 13 and housing 26 of the third flexible mesh gear device 30. The internal gear 43 has the combined structure and function of the internal gear 13 and housing 26 of the third flexible mesh gear device 30.

[0025] That is, in the fourth flexible mesh gear device 40, the difference in axial length between the first flexible mesh gear device 10 and the fourth flexible mesh gear device 40 is compensated for by the spacer member, which is a connecting member. This allows the internal gear 13, as well as the output member 15 including the main bearing 17, to be common to the first flexible mesh gear device 10. This in turn reduces the number of processing steps.

[0026] [others] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. For example, in the above embodiment, the housing 16 (or the internal gear 13) is fixed to the outside, and the output is taken from the output member 15. However, these may be reversed, with the output member 15 fixed, and the output taken from the housing 16 (or the internal gear 13). In the first flexible mesh gear device 10, the housing 16 may be integrated with the internal gear 13. Furthermore, in the series of flexible mesh gear units according to the present invention, it is sufficient that at least one of the gear components (external gear, internal gear) is common between the two flexible mesh gear units. For example, in the above embodiment, the components of the second flexible mesh gear unit 20 other than the external gear and the housing are common to the first flexible mesh gear unit 10. However, as long as at least one of the gear components (external gear, internal gear) is common, the components other than the external gear and the housing do not need to be common. For example, the first flexible mesh gear unit and the second flexible mesh gear unit 20 may have different rolling elements in the main bearing 17, different oil seals 16c, or different numbers of components. Furthermore, in the above embodiment, the housing 26 and the spacer member 38 serving as connecting members are each composed of a single component. However, the housing 26 and the spacer member 38 may each be composed of multiple components. In other words, the connecting member may be composed of multiple components.

[0027] In the above embodiment, a so-called cup-type flexible mesh gear device has been described as an example of a flexible mesh gear device. However, the flexible mesh gear device according to the present invention is not limited to the cup-type, and can also be suitably applied to, for example, a top hat-type gear device. In addition, the details shown in the above embodiment can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0028] 10, 20, 30, 40 flexure mesh gear device 11 Vibrator 12, 22 External gear 12a, 22a Cylindrical part 12b External teeth 12c boss part 13, 43 Internal gear 13a Internal teeth 13b End face 14 Vibrator bearing 15 Output member 15a End face (mating position) 16, 26 Housing (connecting member) 16a, 26a flange 16b End face (mating position) 17 Main bearing 38 Spacer member (connecting member) Ax rotation axis

Claims

1. A series of flexure-mesh gearings including a first flexure-mesh gearing and a second flexure-mesh gearing, each of the first flexible mesh gear set and the second flexible mesh gear set includes a gear component and a main bearing; At least one of the gear components is common between the first flexible mesh gear device and the second flexible mesh gear device, The second flexible mesh gear device is an axial distance between the gear component and the main bearing is longer than that of the first flexible mesh gear device by a predetermined distance difference; The gear component and the main bearing are connected via a connecting member that fills the distance difference. A series of flexible mesh gear units.

2. the gear component includes an external gear that is subject to flexural deformation and an internal gear that meshes with the external gear, The second flexible mesh gear device is the internal gear is common to that of the first flexible mesh gear device, The connecting member is a housing that connects the internal gear and the main bearing.

2. A series of flexible mesh gearing according to claim 1.

3. the gear component includes an external gear that is subject to flexural deformation and an internal gear that meshes with the external gear, The second flexible mesh gear device is the external gear is common to that of the first flexible mesh gear device, the connecting member is a spacer member that connects the external gear and the main bearing, 3. A series of flexible mesh gear units according to claim 1 or claim 2.

4. The first flexible mesh gear device and the second flexible mesh gear device are a housing; and an output member supported by the housing via the main bearing, The distances in the axial direction between the mating position of the housing and the mating position of the output member are different from each other.

2. A series of flexible mesh gearing according to claim 1.

5. The housing and the outer ring of the main bearing are separate bodies.

5. A series of flexible mesh gearing according to claim 4.

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