JP4749697B2 - Eccentric rocking speed reducer - Google Patents

Description

  The present invention relates to an eccentric oscillating speed reducer that decelerates and extracts an eccentric motion of a pinion, and more particularly to an eccentric oscillating speed reducer with a brake.

  For example, a drive device that drives a robot arm includes a servo motor and a speed reducer that decelerates the rotation of the servo motor. Since such a robot arm must be stopped reliably, the brake means Is incorporated.

  Conventionally, such a brake means 3 is arranged between the servo motor 1 and the eccentric oscillating speed reducer 2 and connected to the output shaft 1a of the servo motor 1 as shown in FIG.

  However, in such an eccentric oscillating speed reduction device, since at least the servo motor 1 and the brake means 3 are stacked in the axial direction, there is a problem that the overall axial length becomes long.

  In Patent Document 1 (Japanese Utility Model Publication No. 2-45554), as a solution to this problem, a case in which teeth are formed on the inner periphery, and the teeth housed in the case and meshed with all the teeth are used. In an eccentric motion reduction device comprising a pinion that moves slightly eccentrically, a pair of crank pins inserted in the radially outer end of the pinion, and a carrier that rotatably supports the crank pin. There has been proposed an eccentric type speed reducer characterized in that a brake means for applying a braking force is connected to one of the crankpins, and a detecting means for detecting information relating to rotation is connected to the other crankpin.

Japanese Utility Model Publication 2-45554

In the speed reducer disclosed in Patent Document 1, a brake is provided only on one crankshaft. Therefore, for an eccentric oscillating speed reducer with a large output torque, if a predetermined braking force is to be secured, It is necessary to provide many friction plates in the axial direction, and the crankshaft and the brake become longer in the axial direction. As a result, an eccentric oscillating speed reducer that is long in the axial direction is obtained.

The present invention eliminates the problems associated with the prior art described above and provides an eccentric oscillating speed reducer with a brake having a plurality of first friction plates and a plurality of second friction plates in order to obtain a predetermined braking force. An object of the present invention is to provide an eccentric oscillating speed reducer that is short in the axial direction by reducing the number of axial friction plates .

In the present invention, the above-mentioned object is achieved by engaging an internal gear body having internal teeth, an external gear having external teeth meshing with the internal teeth of the internal gear body, and an eccentric gear, and the external gear. In an eccentric oscillating type speed reducer comprising: a plurality of crank mechanism members configured to rotate; and a support body that rotatably supports the plurality of crank mechanism members, wherein rotation is output from the internal gear body or the support body. Means are provided on at least two of the plurality of crank mechanism members, and the brake means are attached to the plurality of first friction plates provided on the crank mechanism member so as to be movable in the axial direction, the support body. An internal tooth body, and a plurality of second friction plates provided on the internal tooth body so as to be axially movable and frictionally engageable with the first friction plate, and each brake means are arranged in the same plane. An eccentric oscillating speed reducer characterized by More accomplished.

In the present invention, since the brake means is provided on at least two of the plurality of crank mechanism members, the braking load of each brake means can be reduced, and the number of friction plates of each brake means can be reduced. An eccentric oscillating speed reducer with a short axial length is provided.

  Furthermore, in the present invention, it is preferable that the brake means is provided on all of the plurality of crank mechanism members. By doing so, an eccentric oscillation type speed reducer that is shorter in the axial direction can be obtained.

  Further, in the present invention, since each of the brake means is provided at the end of the crank mechanism member, the brake means can be easily attached to the crank mechanism member.

  Further, in the present invention, it is preferable that the motor mounting hollow member is located at the peripheral portion of the brake means and is mounted on the end portion of the internal gear body. Can protect the brake means and can have two functions of mounting a motor and can be used effectively.

  Further, as shown in the embodiment, in the present invention, the brake means includes a first friction plate provided on the crank mechanism member so as to be movable in an axial direction, an internal tooth body attached to the support, A second friction plate provided in the inner tooth body so as to be movable in the axial direction and capable of frictional engagement with the first friction plate, and slidably provided in the motor mounting hollow member. A piston for moving the friction plate in the axial direction, and pressing means for pressing the piston in the direction of the friction plate, and the piston is disposed between the inner periphery of the motor mounting hollow member and the outer periphery of the piston. By forming the hydraulic chamber to be moved, the inner periphery of the mounting hollow member can be used more effectively by making it a hydraulic chamber for moving the piston.

  The present invention may be a center crank type eccentric oscillating speed reducer in which the crankshaft is in the center of the external gear, or any of the eccentric oscillating speed reducers in which the crank mechanism members are arranged equally around the rotation center. It can also be applied to. In particular, when the present invention is applied to an eccentric oscillating speed reducer other than the center crank type, the plurality of crank mechanism members are provided to engage with external gears at positions spaced radially from the rotation center. Preferably, at least one of the crank mechanism members is provided with an input gear, and rotational power is input from the input gear. By doing so, the crank mechanism member can be provided with the input gear and the brake and can be used effectively.

  In this case, it is preferable that a motor having an output rotating shaft is attached to an end of the motor mounting hollow member, and rotational power is input from the output rotating shaft to the input gear. Thereby, an eccentric oscillating speed reducer with a motor short in the axial direction can be obtained.

  In the present invention, since the brake means is provided on at least two of the plurality of crank mechanism members, the braking load of each brake means can be reduced, and the number of friction plates of each brake means can be reduced. Thus, an eccentric oscillating speed reducer that is short in the axial direction is provided.

  Hereinafter, referring to the accompanying drawings illustrating an embodiment of the present invention of an eccentric oscillating type speed reducer that is not a center crank type, that is, an eccentric oscillating type speed reducer in which crank mechanism members are arranged equally around a central axis. The present invention will be described in detail.

  In this embodiment, as shown in FIG. 1, a motor 10 and an eccentric oscillating speed reducer 20 are provided vertically in a vertical direction, and a hollow cylindrical shape is formed on a flange portion 11 on the output shaft 10 a side of the motor 10. The eccentric oscillating speed reducer 20 is fixed via the hollow member 50. That is, the hollow member 50 has a ring-shaped first member 51 and a second member 52 that are coupled vertically, and the second member 52 and the flange portion 11 of the motor 10 are fastened with the bolts 12. The internal gear body 21 of the eccentric oscillating speed reducer 20 is fixed to the first member 51 by the bolt 13.

  The internal gear body 21 has internal teeth 21a on its inner surface. In this embodiment, the internal gear 21 is configured by attaching the internal pins 21a to the inner surface of the internal gear body 21 at equal intervals.

  The external gear 23 of the eccentric oscillating speed reducer 20 has external teeth having a slightly smaller number of teeth than the internal teeth 21 a of the internal gear body 21, and meshes with the internal teeth of the internal gear body 21. Are provided in two rows.

  A hollow portion is formed inside the internal gear body 21, and a support body 25 is rotatably supported by upper and lower main bearings 24a and 24b in the hollow portion. In the support body 25, three column portions 25a are equally formed around the vertical axis. A disk-shaped part 31 is fixed to the column part 25a by a positioning pin 29 and a bolt 30, and the support main body 25 and the disk-shaped part 31 constitute a support body of the present invention.

  In this embodiment, the lower main bearing 24b is a normal angular ball bearing, and the upper main bearing 24a is a tapered roller bearing.

  A plurality of (three in this embodiment) crank mechanism members 27 are arranged around the vertical axis by upper and lower conical bearings 28 around the vertical rotation axis of the motor 10 and the eccentric oscillating speed reducer 20 in the support body 25. Is rotatably supported. The crank mechanism members 27 are alternately positioned with the column portions 25a around the above-described vertical rotation axis. Each crank mechanism member 27 is engaged with the external gear 23 via the needle bearing 26 and swings the external gear 23.

  Of the conical bearings 28 that rotatably support the crank mechanism member 27, the lower conical bearing 28 is provided in the disc-shaped portion 31.

  A flange portion 21a is formed on the upper end surface of the internal gear body 21, and a mounting hole 21b for mounting to another mounting member (not shown) is formed in the flange portion 21a.

  A pinion gear 35 is splined to the upper end surface of the support main body 25, and is fixed to the support main body 25 by a press plate 36 and a presser bolt 33 so that the pinion gear 35 does not come out of the support main body 25.

  A cylindrical auxiliary seal ring 38 is screwed onto a screw formed on the support body 25 above the upper main bearing 24 a of the support body 25. A seal housing body 39 provided outside the seal auxiliary ring 38 is fixed to the flange portion 21a by bolts 40, and oil seals 41 are housed in the seal housing body 39 in two upper and lower stages.

  A small gear 43 is attached to or integrally formed with the upper end portion of the output shaft 10a of the motor 10 described above, and the small gear 43 is screwed with the lower end portion of the crank mechanism member 27 described above. A large spur gear 42 is attached.

  The above configuration is a configuration of a normal eccentric oscillating speed reducer with a motor, and the rotation of the output shaft of the motor 10 is transmitted to the large spur gear 42 of the crank mechanism member 27 via the small gear 43, whereby the crank mechanism member. 27 is rotated, and the support body 25 and the internal gear body 21 are rotated relative to each other by the rotation of the crank mechanism member 27 so as to decelerate.

  In this case, the support main body 25 rotates by fixing the internal gear body 21 to an attachment member (not shown), and the output can be taken out from the pinion gear 35. On the contrary, by fixing the pinion gear 35 of the support body 25, the flange portion 21a of the internal gear body 21 rotates, and the output can be taken out from the flange portion 21a.

  In the present invention, the brake means 70 is provided at the lower end of the crank mechanism member 27 configured as described above. The brake means 70 is provided on at least two of the plurality of crank mechanism members 27.

  The brake means 70 of the present invention will be described with reference to FIGS. A plurality of first friction plates 53 are splined to the lower end portion of the crankshaft 27a of the crank mechanism member 27 at equal intervals in the vertical direction so as to be movable up and down along the crankshaft 27a. Is not rotated relative to the crankshaft 27a, but rotates integrally. A lining member 54 is affixed to both the upper and lower sides of each first friction plate 53 to form a brake shoe 57.

  On the other hand, as shown in FIG. 1, an internal tooth body 55 having a ceiling on the upper side and a triangular recess 55b for accommodating three brake means 70 as shown in FIG. The bottom of the shaped part 31 is attached by a bolt 56. As shown in FIG. 2, an inner tooth 55a as shown in FIG. 2 is formed on the inner peripheral surface of the triangular recess 55b. The second tooth plate 55 has an outer tooth 58a that engages with the inner tooth 55a. 58 is provided to be movable in the vertical direction with respect to the internal tooth body 55. The outer periphery of the first friction plate 53 does not reach the inner periphery of the internal tooth body 55, and the inner periphery of the second friction plate 58 does not reach the outer periphery of the crankshaft 27a. Since the external teeth 58a of the second friction plate 58 mesh with the internal teeth 55a of the internal tooth body 55, the second friction plate 58 does not rotate relative to the internal tooth body 55 but only in the axial direction. It is slidable.

  The lower end portion of the hollow member 50 described above projects inwardly to form a shoulder portion 50a, and the piston 60 with the step 60a that is shaped to engage with the shoulder portion 50a can slide on the lower end portion of the hollow member 50. The seal members 61 and 62 made of O-rings are mounted between the hollow member 50 and the piston 60, so that the piston 60 can slide up and down in the hollow member 50. It is in a state of being tightly fitted to the. A hydraulic chamber 63 is formed between the shoulder 50 a of the hollow member 50 and the stepped portion 60 a of the piston 60, and oil is introduced into the hydraulic chamber 63 from an introduction hole 64 formed in the hollow member 50. The piston 60 is moved downward by the introduction of oil. On the other hand, a pressing member such as a compression spring 65 is provided at the lower part of the piston 60, and always presses and urges the piston 60 upward.

  With the above configuration, when oil is introduced from the oil introduction hole 64 into the hydraulic pressure chamber 63, the piston 60 is moved downward against the pressing force of the compression spring 65, whereby the first friction plate of the crankshaft 27a. 53 and the contact of the internal tooth body 55 with the second friction plate 58 are released, and the crankshaft 27a freely rotates. On the other hand, by stopping the introduction of oil into the hydraulic pressure chamber 63, the piston 60 is pressed upward by the compression spring 65, whereby the first friction plate 53 and the internal tooth body 55 provided on the crankshaft 27a are provided. The second friction plate 58 is frictionally engaged so that the brake is applied to the crank mechanism member 27.

  In the above embodiment, the crank mechanism member 27 is provided equidistantly around the output shaft 10a of the motor 10 with an interval of 120 °, and the brake means 70 is provided in at least two of them. . Preferably, the brake means 70 is provided on all of the three crank mechanism members 27 because the braking force is increased, and the size of the brake itself in the longitudinal direction can be reduced to make the entire apparatus compact.

  Further, the brake means 70 is preferably provided at the outer end portion of the crank mechanism member 27 as in the above-described embodiment, so that the mounting adjustment of the brake means 70 and the like can be performed very easily.

  Further, as shown in the embodiment, the motor mounting hollow member 50 is positioned around the brake means 70 and attached to the end of the internal gear body 21, so that the motor mounting hollow member 50 causes the brake means 70 to be externally attached. There is an advantage that the motor 10 and the eccentric oscillating speed reducer 20 can be easily attached while protecting.

  Further, as shown in the embodiment, the piston 60 is mounted on the hollow member 50, and the hydraulic chamber 63 for operating the piston 60 is formed between the hollow member 50 and the piston 60, so that the brake can be applied with a compact configuration. Can be operated.

  In the above-described embodiment, the type in which the crank mechanism member 27 is equally provided around the central axis has been described. However, in the present invention, the crankshaft for eccentrically swinging the external gear is the internal tooth 21a. It can also be applied to a so-called center crank type eccentric oscillating speed reducer on the center line.

  When the center swing type is not used as in the above-described embodiment, the crank mechanism member 27 is provided equally around the output shaft of the motor 10, and a plurality of crank mechanism members are provided from the output shaft of the motor 10. A brake may be provided on the other two crank mechanism members 27 by inputting a rotational force to at least one of the two 27.

It is a longitudinal cross-sectional view of one Example of this invention. It is AA sectional drawing of FIG. It is an expanded sectional view of the brake means of FIG. It is the schematic made into the partial cross section of the conventional apparatus.

Explanation of symbols

21 Internal gear body 23 External gear 27 Crank mechanism member 25 Support body 31 Disk-shaped part
53 First friction plate
55 Internal teeth
58 Second friction plate 70 Brake means

Claims (7)

An internal gear body having internal teeth, an external gear having external teeth meshing with the internal teeth of the internal gear body, eccentrically swinging, a plurality of crank mechanism members engaged with the external gear, and An eccentric oscillating type speed reducer that outputs rotation from the internal gear body or the support body, and a brake means is provided on the plurality of crank mechanism members. A plurality of first friction plates provided in at least two, the brake means being provided on the crank mechanism member so as to be movable in the axial direction; an internal tooth body attached to the support; and the internal tooth body A plurality of second friction plates provided so as to be movable in the axial direction and capable of frictional engagement with the first friction plate, and the brake means are arranged in the same plane, Dynamic reducer. 2. The eccentric oscillating speed reducer according to claim 1, wherein the brake means is provided on all of the plurality of crank mechanism members. The eccentric oscillating speed reducer according to claim 1 or 2, wherein each of the brake means is provided at an end of the crank mechanism member. 4. The eccentric oscillating speed reducer according to claim 3, wherein a motor mounting hollow member is positioned at a peripheral portion of the brake means and is attached to an end portion of the internal gear body. The brake means includes a piston that is slidably provided on the motor mounting hollow member and moves the first and second friction plates in the axial direction, and a pressing means that presses the piston toward the friction plate. The eccentric rocking type reduction gear according to claim 4, further comprising: a hydraulic chamber that moves the piston between an inner periphery of the motor mounting hollow member and an outer periphery of the piston. The plurality of crank mechanism members are provided in engagement with external gears at positions spaced radially from the output rotation center, and at least one of the crank mechanism members is provided with an input gear. The eccentric oscillating speed reducer according to any one of claims 1, 2, 4, and 5, wherein: The eccentric oscillation according to claim 6, wherein a motor having an output rotation shaft is attached to an end of the motor mounting hollow member, and rotational power is input from the output rotation shaft to the input gear. Type reducer.

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