JP2002021866A - Wave motion gear device unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fasten a bearing inner ring rotatably supporting a flexible external gear of a wave motion gear reducer rotatably against a cylindrical housing on the flexible external gear by one time screw tightening operation. SOLUTION: A wave motion gear device unit 1 has a wave motion gear reducer 3 arranged in a cylindrical housing 2 and a cup shaped flexible external gear 6 as an output element supported by the housing 2 through a cross roller bearing 4. An inner ring 12 of the cross roller bearing 4 is threadedly fixed on an external screw 33 formed on an outer periphery surface of a boss 63 of the flexible external gear 6. In addition to a threaded hole 14, a pair of pin holes 28, 28 are formed on an outer side end surface 12a of the inner ring 12. When the inner ring 12 is fastened on the flexible external gear 6 by a thread tightening action, the inner ring 12 can be fixed or rotated by using the pinholes 28, 28. The inner ring 12, thereby, is easily fastened on the flexible external gear 6 by one time screw tightening operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wave gear device unit having a structure in which a wave gear reducer is incorporated in a cylindrical housing. More specifically, the present invention relates to a flexible external tooth of a wave gear reducer. The present invention relates to a structure for fixing an inner race in a bearing that rotatably supports a gear in a housing.

[0002]

2. Description of the Related Art FIG. 3 shows such a wave gear unit. As shown in this figure, a wave gear device unit 100 has a cylindrical housing 101, a wave gear reducer 102 incorporated therein, and a reduced rotation output element of the wave gear reducer 102 in a rotatable state. And a cross roller bearing 103 supported on the housing 101 side. The wave gear reducer 102 is an annular rigid internal gear 104 fixed to the inner peripheral surface of the housing.
And a cup-shaped flexible external gear 105 disposed inside the inside, and a wave generator 106 having an elliptical contour fitted inside the inside.

The cross roller bearing 103 includes an outer ring 108 fixed to a housing end face 107 and an inner ring 11 fixed to a boss 109 of a cup-shaped flexible external gear 105.
0 and a roller 111. The inner ring 110 functions as an output flange, and a screw hole 115 for a fastening bolt for connecting and fixing a member on the load side is formed on the outer end face.

[0004] The outer race 108 is penetrated by a plurality of fastening bolts 114 which are screwed into screw holes formed in the housing end surface 107 through the outer race.
07.

On the other hand, a circular concave portion is formed on the inner end surface of the inner race 110, and a female screw 11 is formed on the inner peripheral surface.
6 are formed. Boss 10 of flexible external gear 105
Reference numeral 9 denotes an annular shape, and an external thread 117 is provided on its outer peripheral surface.
Are formed, and the inner race 110 is screwed and fixed to the boss 109. Therefore, the flexible external gear and the inner ring can be fastened by one screw tightening operation.

[0006]

In the screw tightening operation, the inner ring must be fixed or rotated. As described above, a screw hole for connecting a member on the load side is formed on the outer end surface of the inner ring, so if a fastening bolt is installed in the screw hole, the inner ring is formed using the fastening bolt. It can be fixed or rotated.

However, in this method, an operation of tightening the fastening bolt is required, so that it becomes impossible to fasten the flexible external gear and the inner ring by one screw tightening operation. In this case, the initial purpose of forming a male screw and a female screw on both members and fastening them by one screw tightening operation cannot be achieved.

In view of the above, an object of the present invention is to provide a wave gear device unit having a structure capable of fastening a flexible external gear and an inner ring by a single screw tightening operation.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a cylindrical housing, a wave gear reducer mounted in the housing, and a cup-shaped wave gear reducer. In a wave gear unit having a bearing rotatably supporting a flexible external gear in the housing, the flexible external gear has a cylindrical body and one end of the body. An annular diaphragm plate extending inward in the radial direction continuously from the diaphragm plate, and a boss formed continuously on an inner peripheral edge of the diaphragm plate;
The bearing includes an outer ring mounted on the housing, an inner ring mounted on the boss, and a plurality of rolling elements mounted between the outer ring and the inner ring; the inner ring has an axial line extending from an outer end face thereof. A pin hole extending in the direction
A female screw portion formed on an inner peripheral surface thereof, and the flexible external gear includes a male screw portion formed on an outer peripheral surface of the boss,
The boss is screwed and fixed to the inner race.

In the wave gear device unit having this configuration, when the inner ring and the flexible external gear are screwed together, the inner ring can be fixed or rotated using a pin hole formed in the inner ring. That is, by attaching a pin to a jig for fixing or rotating the inner ring and inserting the pin into the pin hole, the inner ring can be securely fixed or rotated. Therefore, the inner ring and the flexible external gear can be performed by one screwing operation.

If the boss has a through hole having a polygonal cross section at the center thereof, the fixing or rotation of the flexible external gear can be easily performed using the through hole having the polygonal cross section. it can. Therefore, the work of screwing both members is simplified.

The bearings include, for example, a cross roller bearing and a four-point contact bearing.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a wave gear device unit to which the present invention is applied will be described below with reference to the drawings.
1A and 1B are a cross-sectional view and an end view showing a wave gear device unit of the present example, and FIG. 2 is an enlarged partial cross-sectional view showing a cross roller bearing in an enlarged manner.

The wave gear unit 1 of the present embodiment includes a cylindrical housing 2, a wave gear reducer 3 mounted inside the housing 2, and a reduced rotation output element of the wave gear reducer 3 in the housing 2. And a cross roller bearing 4 which is supported in a rotatable state with respect to.

The wave gear reducer 3 includes an annular rigid internal gear 5, a cup-shaped flexible external gear 6 which is a reduction rotation output element, and a wave generator 7 having an elliptical contour. .
The rigid internal gear 5 is fitted and fixed in an annular step 8 formed on the inner peripheral surface of the housing 2. The cup-shaped flexible external gear 6 includes a cylindrical body portion 61 and an annular diaphragm plate 6 extending radially inward from one end edge thereof.
2 and an annular boss 63 formed continuously and integrally with the inner peripheral edge of the diaphragm plate 62. The wave generator 7 includes a hollow input shaft 71 into which a high-speed rotation input shaft (not shown) such as a motor is inserted and fixed, a rigid cam plate 72 having an elliptical contour fitted on the outer periphery thereof, and a rigid cam plate 72. A wave bearing 73 fitted on the outer peripheral surface is provided.

On the other hand, the cross roller bearing 4 has an outer ring 11 attached to the inner peripheral surface of the housing, an inner ring 12 attached to the outer peripheral surface of the boss 63 of the flexible external gear 6, and an annular ring formed by these. A plurality of rollers 13 are provided in the track so that the rotation axes are alternately orthogonal to each other in the circumferential direction.

In this embodiment, the inner ring 12 functions as an output flange which is connected and fixed to a member (not shown) on the load side, and has an outer end face for mounting at a constant angular interval in the circumferential direction. A screw hole 14 is formed. In addition, a pair of pin holes 2 are formed on the outer end surface 12a of the inner race 12.
8, 28 are formed. As will be described later, the pin holes 28 are rotation-preventing holes used for fixing or rotating the inner ring 12 when the inner ring 12 and the flexible external gear 6 are fastened by screwing.

Next, with reference mainly to FIG. 2, the structure of the portion centering on the cross roller bearing 4 will be described in detail. First, the outer race 11 has a V-shaped outer raceway surface 15 on the inner circumferential surface.
Are formed, and a thin annular projection portion 17 whose outer peripheral portion only protrudes in the direction of the device axis 1a from the outer end surface of the annular shape. An annular oil seal 19 is mounted between the annular projection 17 and the outer peripheral surface 18 of the inner race 12.

Here, a male screw portion 20 is formed from the outer peripheral surface of the outer ring main body portion 16 to the outer peripheral surface of the annular projection portion 17. An inner peripheral surface 21 having a diameter larger than that of an adjacent inner peripheral surface is formed at one end opening edge portion of the housing 2, and a portion of the inner peripheral surface 21 on the opening edge side is screwed to the male screw portion 18. A possible female thread 22 is formed.
The outer ring 11 is screwed and fixed to the opening edge portion of the housing 2.
Is in contact with an annular step surface 24 on the housing side. Since the end faces contact each other in this manner, the assembling accuracy of the outer ring 11 with respect to the housing 2 can be improved.

A plurality of engaging recesses 27 are formed at regular angular intervals in the circumferential direction from the outer end surface 25 of the annular projection portion 17 of the outer race 11 to the outer peripheral surface 26 thereof. The engagement concave portion 27 connects the outer race 11 to the housing 2.
When the outer ring 11 is screwed into the outer ring 11, the outer ring 11 can be screwed with a sufficient fastening rotational force by hooking a fastening jig. Instead of the engagement recess 27, an engagement protrusion may be formed.

Further, in this embodiment, when viewed along the direction of the apparatus axis 1a, the center position C of the roller 13 is larger than the screw fastening portion A composed of the male screw portion 20 and the female screw portion 22 and the annular end face 23 Surface contact position B by the annular step surface 24
Is located on the side of. When such an arrangement is adopted, the deformation of the outer race 11 can be suppressed. This is particularly effective when the outer race 11 is thin.

Next, the inner ring 14 and the flexible external gear 6 are also connected and fixed in a screwed state. That is, on the inner end face side of the annular inner ring 14, the center through hole 3 is formed.
1 has a large diameter, and a female screw part 32 is formed on the inner peripheral surface of the large diameter hole.
3 is formed on the outer peripheral surface of the boss 63. Also in this case, the annular step surface 64 formed inside the through hole is provided.
And the annular end face 65 formed on the side of the boss 63 are in surface contact with each other, and the assembling accuracy thereof is increased.

In this embodiment, a through hole having a polygonal cross section is formed at the center of the boss 63. For example, a through-hole 63a having a hexagonal cross section is formed. These parts are adhered and fixed with an adhesive in order to prevent loosening in a screw fastening portion between the outer ring 11 and the housing 2 and a screw fastening portion between the inner ring 12 and the boss 63 of the flexible external gear. ing. As a loosening prevention mechanism or a loosening prevention mechanism,
These screw fastening parts may be plastically deformed. Alternatively, a fitting member may be interposed between these screw fastening portions.

Note that a ball bearing, for example, a four-point contact bearing, can be used instead of the cross roller bearing. Of course, other bearings can be used.

In the wave gear device unit 1 of the present embodiment configured as described above, when the flexible external gear 6 and the inner ring 12 are fastened, the inner ring 12 is fixed using the pin hole 28 on the inner ring side. Alternatively, it can be rotated. Further, a through hole 63 having a hexagonal cross section formed in the boss 63 of the flexible external gear 6.
By using a, the flexible external gear 6 can be fixed or rotated. Therefore, these pin holes 28, pins that just fit into the through holes 63a having a hexagonal cross section,
If these members are attached to the screw fastening jig,
The fastening of steps 2 and 6 can be performed by one screw tightening operation, and can be performed by a sufficient screw rotating force.

[0026]

As described above, the present invention relates to a wave gear device unit having a structure in which a wave gear reducer is built in a cylindrical housing. The inner ring of the bearing supporting the flexible external gear in the housing in a rotatable state and the boss of the flexible external gear can be screwed and fixed, and the inner ring can be fixed or fastened at the time of tightening. A pin hole that can be used for rotation is formed on the outer end face of the inner ring.

Therefore, according to the present invention, the inner ring is fixed or rotated when the inner ring and the flexible external gear are fastened by an extremely inexpensive method using a pin hole formed in the inner ring. Can be. Therefore, both members can be easily fastened by one screw tightening operation.

[Brief description of the drawings]

FIG. 1 is a sectional view and an end view showing a wave gear device unit to which the present invention is applied.

FIG. 2 is a partially enlarged cross-sectional view showing a cross roller bearing in FIG.

FIG. 3 is a cross-sectional view and an end view showing a conventional wave gear device unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wave gear unit 1a Device axis 2 Housing 3 Wave gear reducer 4 Cross roller bearing 5 Rigid internal gear 6 Cup-shaped flexible external gear 7 Wave generator 63 Boss 63a Hexagonal section through hole 11 Outer ring 12 Inner ring 12a Outer end face of inner ring 13 Roller 14 Mounting hole 20 Male thread 22 Female thread 23 Annular end face 24 Annular stepped surface 27 Engagement recess 28 Pin hole 32 Female thread 33 Male thread

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoshiji Nakazawa 1856-1, Maki, Hodaka-cho, Minamiazumi-gun, Nagano Pref. FA18 GB03 GC07 GD03 GD08 GD12 GE25 3J101 AA04 AA26 AA42 AA54 AA62 BA53 BA54 BA56 FA46 GA60

Claims (3)

[Claims] 1. A cylindrical housing, a wave gear reducer mounted in the housing, and a cup-shaped flexible external gear of the wave gear reducer supported by the housing in a rotatable state. In the wave gear device unit having a bearing, the flexible external gear has a cylindrical body, and an annular diaphragm plate extending inward in the radial direction continuously to one end of the body, A boss formed continuously on an inner peripheral edge of the diaphragm plate; and the bearing is mounted between an outer ring attached to the housing, an inner ring attached to the boss, and the outer ring and the inner ring. The inner ring has a pin hole extending in the axial direction from an outer end surface thereof, and a female screw portion formed on the inner peripheral surface thereof, and the flexible external gear Is that boss A wave gear unit comprising: a male thread portion formed on an outer peripheral surface; and the boss is screwed and fixed to the inner ring. 2. The wave gear unit according to claim 1, wherein the boss has a through hole having a polygonal cross section at the center thereof. 3. The wave gear unit according to claim 1, wherein the bearing is a cross roller bearing or a four-point contact bearing.