CN218326033U - Speed reducer - Google Patents

Abstract

The utility model provides a speed reducer, which can improve the rigidity and can be used as a speed reducer with improved working reliability. The speed reducer (1) has a housing (2); the deceleration part (3) has a gear frame part (20) arranged to the inner side of the housing in a manner capable of relative rotation around a rotation axis (O), so that the driving part ( M) The input rotation is decelerated and output. The deceleration part has a crankshaft (30), has an eccentric part (31), and rotates with the rotation from the drive part, and a swing gear (40), which swings and rotates with the rotation of the eccentric part. The rack portion cooperates with the swing gear. A transmission gear (36) is attached to the crankshaft, and is arranged on the outer side of the gear carrier along the rotation axis to transmit the rotation from the drive unit. The carrier part has a reinforcing part (100) formed to protrude outward along the rotation axis from an end surface (80a) of the carrier part opposite to the transmission gear in the direction of the rotation axis.

Description

reducer

technical field

The utility model relates to a reducer.

Background technique

Conventionally, for example, industrial robots, machine tools, and the like have incorporated motor units having speed reducers. In an articulated robot, which is one type of industrial robot, for example, a motor unit is often incorporated in a connecting portion (joint portion) of each arm constituting the robot.

Such a motor unit mainly includes a drive motor and a speed reducer that is driven by the drive motor. Thereby, the motor torque generated by the rotation of the drive motor can be decelerated by the speed reducer, and can be output to each arm. In particular, by using a speed reducer, for example, the output (high-speed rotation and low torque) of a drive motor can be converted into low-speed rotation and high torque, and output to each arm.

As such a speed reducer, for example, Patent Document 1 discloses an eccentric oscillating type speed reducer.

This speed reducer mainly includes: a case; a carrier portion disposed inside the case so as to be relatively rotatable about an axis; and a plurality of crankshafts rotatably supported by the carrier portion, and, It has an eccentric part; and a plurality of oscillating gears which eccentrically oscillate around the axis by the rotation of the eccentric part accompanying the rotation of each crankshaft. The swing gear has external teeth that mesh with internal teeth formed on the housing and have a different number of teeth, and the external teeth swing and rotate while meshing with the internal teeth.

Furthermore, the speed reducer has a structure in which transmission gears (spur gears) connected to the respective crankshafts are disposed on the outer side in the axial direction than the carrier portion. Specifically, it is disposed on the outer side in the axial direction than the second carrier portion constituting the carrier portion.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2015-83329

Utility model content

Problems to be solved by the utility model

In the future, reduction gears combined with articulated robots will be required to be more compact, more precise, and more rigid. For high rigidity, for example, moment rigidity, torsional rigidity, and the like can be cited.

Regarding this point, in the above-mentioned conventional speed reducer, the transmission gear is arranged on the outside of the second carrier portion in the axial direction. Therefore, the thickness of the second carrier portion along the axial direction becomes thinner. It is easy to have a thin-walled structure. Therefore, there exists a tendency for the rigidity of a 2nd carrier part to fall easily.

Therefore, when the bearing for pivotally supporting the crankshaft, for example, is provided between the crankshaft and the second carrier portion, problems such as deformation of the second carrier portion may occur due to stress transmitted through the bearing, and there is a need for improvement. room.

In particular, since the crankshaft becomes longer because the transmission gear is disposed on the outside in the axial direction than the second carrier portion, stress tends to act on the second carrier portion via the bearing. Therefore, the above-mentioned disadvantages are more concerned.

This invention is made|formed in view of such a situation, and it aims at providing the speed reducer which can improve rigidity.

solutions to problems

(1) A technical solution of the speed reducer of the present invention includes: a housing configured to be rotatable around a rotation axis; The carrier part inside the case decelerates the rotation input from the drive part and outputs it. The reduction unit includes: a crankshaft having an eccentric portion that is eccentric with respect to the rotation axis and that rotates as the drive unit rotates; and a swing gear that rotates around the eccentric portion as the eccentric portion rotates. The axis of rotation swings and rotates. The carrier portion cooperates with the swing gear. A transmission gear is attached to the crankshaft. The transmission gear is arranged on the outer side of the carrier portion along the rotation axis and transmits rotation from the drive portion. The carrier portion has a reinforcing portion formed to protrude outward along the rotation axis from an end surface of the carrier portion opposite to the transmission gear in the direction of the rotation axis.

According to this speed reducer, the rotation input from the drive unit such as the drive motor can be decelerated and output by the deceleration unit arranged so as to be relatively rotatable inside the casing. Specifically, for example, when the housing is fixed, the crankshaft can be rotated according to the rotation of the drive unit such as the drive motor, and the eccentric unit can also be rotated. Thereby, it is possible to cause the swing gear to swing and rotate around the rotation axis in accordance with the rotation of the eccentric portion. In this case, the carrier cooperates with the swing gear so as to allow the swing rotation of the swing gear while restricting the autorotation of the swing gear. Therefore, the decelerated rotation can be output via the carrier, for example.

In particular, since the transmission gear attached to the crankshaft is disposed outside the carrier portion, it is easy to transmit the rotation from, for example, the drive motor to the transmission gear, and it is easy to assemble the speed reducer. Even if the transmission gear is arranged on the outer side of the carrier portion in this way, a reinforcing portion protruding outward along the rotation axis is formed on the end surface of the carrier portion. Therefore, the thickness along the rotation axis can be thickened in accordance with the formation of the reinforcing portion, and the rigidity of the carrier portion itself can be increased to increase the rigidity.

Therefore, troubles such as deformation of the carrier portion due to stress transmitted from the crankshaft, for example, to the carrier portion are less likely to occur, and it is possible to provide a speed reducer with improved operational reliability. Furthermore, since the rigidity of the carrier portion can be increased, for example, when the bearing is provided between the carrier portion and the crankshaft, it is possible to appropriately apply a preload to the bearing while suppressing deformation of the carrier portion. As a result, the reliability of operation and the like can be further improved.

(2) A plurality of the crankshafts may be arranged at intervals in a circumferential direction revolving around the rotation axis centering on the rotation axis. The reinforcing portion may include an annular reinforcing ring portion extending in the circumferential direction so as to surround the transmission gears respectively attached to the plurality of crankshafts from the outer side in the radial direction of the housing. .

In this case, not only the reinforcing portion protrudes outward from the end surface of the carrier portion along the rotation axis, but also the plurality of transmission gears can be surrounded from the radially outer side by the annular reinforcing ring portion. In particular, since the reinforcing ring portion can be formed over the entire circumference of the carrier portion, in addition to ensuring the wall thickness of the carrier portion, it is possible to make the carrier portion less likely to be unduly deformed such as strain or warp.

(3) The reinforcement portion may include a reinforcement plate extending from the reinforcement ring portion toward the inside in the radial direction so as to enter between the transmission gears adjacent in the circumferential direction. , and integrally formed with the reinforcing ring portion. The reinforcing plate may be formed to surround the transmission gear.

In this case, since the reinforcement part further has a reinforcement plate, the carrier part can be made thick in a wider range, and rigidity can be effectively improved. Furthermore, the reinforcing plate is formed to surround the transmission gear. Accordingly, it is possible to form the reinforcing plate as wide as possible without hindering the movement of the transmission gear. Furthermore, the transmission gear can be easily protected by the reinforcing plate, and unnecessary contact with the transmission gear from the outside, for example, can be easily avoided.

(4) The reinforcing portion may be formed such that the thinnest portion has a thickness of at least 1 mm or more.

In this case, even the thinnest part of the reinforcing part has a thickness of 1 mm or more, so that it can properly function as the reinforcing part, and the above-mentioned operation and effect can be more reliably exerted.

(5) A technical solution of the speed reducer of the present invention includes: a housing configured to be rotatable around a rotation axis; The carrier part inside the case decelerates the rotation input from the drive part and outputs it. The reduction unit includes: a crankshaft having an eccentric portion eccentric to the rotation axis, rotatably supported by the carrier unit, and rotated by rotation from the driving unit; and a swing gear that swings and rotates about the rotation axis as the eccentric portion rotates. The carrier portion cooperates with the swing gear so as to allow swing rotation of the swing gear and to restrict autorotation of the swing gear. The carrier part includes: a first carrier part; and a second carrier part arranged so as to be aligned with the first carrier part on the axis of rotation and sandwich the swing gear. And combined with the first gear carrier part. A plurality of the crankshafts are arranged at intervals in a circumferential direction revolving around the rotation axis around the rotation axis. A transmission gear is attached to each of the plurality of crankshafts. The transmission gear is arranged on the outer side of the second carrier portion along the rotation axis and transmits rotation from the driving portion. The second carrier portion has a reinforcing portion formed to protrude outward along the rotation axis from an end surface of the second carrier portion opposite to the transmission gear in the direction of the rotation axis. . The reinforcing part includes: an annular reinforcing ring part extending in the circumferential direction so as to surround the transmission gear from the outside in the radial direction of the housing; A way between the circumferentially adjacent transmission gears extends from the reinforcement ring portion toward the inside in the radial direction, and is integrally formed with the reinforcement ring portion. The reinforcing plate is formed to surround the transmission gear.

According to this speed reducer, similarly to the above-mentioned speed reducer, it is possible to achieve improvement in rigidity, and it is possible to provide a speed reducer with improved operational reliability.

In particular, the carrier portion can be composed of a first carrier portion called, for example, a shaft, and a second carrier portion called, for example, a holding flange. In addition, the plurality of crankshafts on which the transmission gears are mounted can be configured as a speed reducer in which the transmission gears are arranged outside the second carrier portion (so-called reverse assembly structure). Therefore, the rotation of the drive motor can be transmitted through, for example, the input shaft at a position outside the second carrier portion through a plurality of transmission gears, and assembly according to the application can be performed. Even in this case, since the reinforcing portion is formed on the end surface of the second carrier portion, the rigidity of the second carrier portion can be increased. Therefore, it can be set as the speed reducer of the reverse assembly structure which improved the reliability of operation.

The effect of utility model

According to the present invention, it is possible to achieve improvement in rigidity, and it is possible to provide a speed reducer with improved operational reliability.

Description of drawings

FIG. 1 is a front view showing a first embodiment of a speed reducer of the present invention.

Fig. 2 is a longitudinal sectional view of the speed reducer along line A-A shown in Fig. 1 .

Fig. 3 is a longitudinal sectional view showing a second embodiment of the speed reducer of the present invention.

Explanation of reference signs

O, axis of rotation; 1, 110, reducer; 2, housing; 3, deceleration part; 20, gear frame part; 30, crankshaft; 31, eccentric part; 36, transmission gear; 40, swing gear; 70, the first 1 gear frame part; 80, the second gear frame part; 80a, rear end face (end face); 100, reinforcement part; 101, reinforcement ring part; 102, reinforcement plate.

detailed description

Hereinafter, a speed reducer according to an embodiment of the present invention will be described with reference to the drawings.

In the following description, there are cases where the same reference numerals are attached to corresponding structures, and descriptions thereof are omitted. Moreover, in the following description, when there are expressions such as "parallel", "orthogonal", "central", "coaxial" and the like indicating a relative or absolute arrangement, not only those expressing such an arrangement strictly A state that is relatively displaced by a tolerance, an angle, and a distance to the extent that the same function can be obtained is also included.

(first embodiment)

As shown in FIGS. 1 and 2 , the speed reducer 1 according to the present embodiment can be suitably used in, for example, an articulated robot (more specifically, a vertical axis independent articulated robot), which is an industrial robot. For example, in an articulated robot, the speed reducer 1 is incorporated in a connection portion (joint portion) between arms that are rotatably connected.

The speed reducer 1 of the present embodiment is an example of a so-called solid type speed reducer 1 in which an input shaft 4 to be discussed later is arranged coaxially with a rotation axis O of the speed reducer 1 . The speed reducer 1 decelerates and outputs rotation (motor torque) input from a drive motor M as a power source.

The speed reducer 1 includes: a housing 2 arranged to be rotatable about a rotation axis O;

In addition, in this embodiment, the direction along the rotation axis O is called an axial direction. In addition, in the axial direction, the side where the input shaft 4 is located is referred to as the rear, and the opposite side is referred to as the front. In addition, when viewed from a plane viewed in the direction of the rotation axis O, a direction intersecting the rotation axis O is called a radial direction, and a direction orbiting around the rotation axis O is called a circumferential direction.

(case)

The case 2 includes a case main body portion 10 and a case flange portion 11 , and functions as a so-called housing case of the speed reducer 1 .

The case main body portion 10 is formed in a cylindrical shape opened at the front and rear. The deceleration unit 3 is accommodated in a relatively rotatable manner inside the housing main body 10 .

The case flange portion 11 protrudes radially outward from the outer peripheral surface of the case body portion 10 , and is formed in an annular shape extending in the circumferential direction over the entire circumference of the case body portion 10 . In the illustrated example, the case flange portion 11 is formed at a position deviated rearward from the central portion in the axial direction of the case main body portion 10 .

However, the position of the case flange portion 11 is not limited to this case, and may be formed, for example, at the central portion in the axial direction of the case body portion 10 , or may be formed at a position relative to the axial direction of the case body portion 10 . The position where the central part is deviated to the front.

A plurality of through-holes 12 and a plurality of screw holes 13 penetrating the case flange portion 11 in the axial direction are formed in the case flange portion 11 . In the illustrated example, four screw holes 13 are formed at equal intervals in the circumferential direction. That is, the plurality of screw holes 13 are arranged at intervals of 90 degrees around the rotation axis O. As shown in FIG. The plurality of through holes 12 are arranged at equal intervals in the circumferential direction so as to be located between the threaded holes 13 adjacent in the circumferential direction.

However, the formation positions, numbers, etc. of the screw holes 13 and the through holes 12 are not limited to this case, and may be appropriately changed. Furthermore, it is not necessarily necessary to form the threaded hole 13, and only a plurality of through holes 12 may be formed, for example.

As shown in FIG. 2 , a first arm R1 constituting a plurality of arms of an articulated robot as an example of an external member is attached to the casing 2 configured as described above. The first arm R1 is combined by, for example, the case flange portion 11 , and is fixed to the case 2 by a fastening member (not shown) or the like through the through hole 12 or the screw hole 13 .

(deceleration part)

As shown in FIGS. 1 and 2 , the deceleration unit 3 includes: a carrier unit 20 rotatably held inside the housing main body unit 10 ; and a crankshaft 30 having an eccentric unit 31 eccentric to the rotation axis O , and is rotatably supported by the carrier portion 20, and the crankshaft 30 rotates with the rotation from the drive motor M; and the swing gear 40 swings around the rotation axis O with the rotation of the eccentric portion 31 rotate.

The carrier portion 20 cooperates with the swing gear 40 so as to allow the swing rotation of the swing gear 40 and restrain the autorotation of the swing gear 40 . Accordingly, the deceleration unit 3 can decelerate the rotation input from the drive motor M and output it.

In the present embodiment, three crankshafts 30 are arranged at equal intervals in the circumferential direction around the rotation axis O. Furthermore, two swing gears 40 are arranged so as to be aligned in the axial direction. Specifically, the swing gear 40 includes: a first swing gear 50 ; and a second swing gear 60 disposed on the rear side of the first swing gear 50 so as to be adjacent to the first swing gear 50 .

Therefore, the speed reducer 1 of the present embodiment is a so-called eccentric swing type speed reducer in which two swing gears 40 (first swing gear 50 and second swing gear 60 ) swing and rotate.

(Input shaft)

As shown in FIG. 2 , the reduction unit 3 receives rotation from a drive motor M via an input shaft 4 . Therefore, the three crankshafts 30 can be rotated by rotating the input shaft 4 , and the rotation from the drive motor M can be transmitted to the speed reduction unit 3 .

The input shaft 4 will be briefly described. In addition, illustration of the input shaft 4 is omitted in FIG. 1 .

The input shaft 4 is arranged coaxially with the rotation axis O, and is arranged on the rear side of the speed reduction unit 3 . Therefore, the input shaft 4 of the present embodiment is not arranged so as to be inserted inside the deceleration unit 3 , but is arranged outside the deceleration unit 3 .

A not-shown base end (rear end) of the input shaft 4 is connected to a not-shown drive shaft of a drive motor M, for example. Accordingly, the input shaft 4 rotates around the rotation axis O as the drive motor M is driven. An input gear 5 is formed on an outer peripheral surface of a distal end portion (tip portion) of the input shaft 4 . The input gear 5 is disposed on the rear end surface 80a side of the second carrier portion 80 to be described later.

In addition, the input shaft 4 is not limited to the case where the input shaft 4 is disposed on the rear side of the speed reduction unit 3 , and the input gear 5 may be disposed on the second gear by being inserted into the inside of the speed reduction unit 3 from the front to the rear, for example. The structure of the rear end surface 80a side of the frame part 80. That is, it only needs to be able to input the rotation from the drive motor M to the deceleration unit 3, and the arrangement of the input shaft 4 may be appropriately changed.

Furthermore, the positional relationship between the drive motor M and the speed reducer 1 is not particularly limited, and the drive motor M may be arranged, for example, on the front side of the speed reducer 1 .

(gear frame part)

As shown in FIG. 2 , the carrier portion 20 is disposed radially inside the case body portion 10 , and is supported by a pair of main bearings 21 so as to be relatively rotatable with respect to the case body portion 10 . Accordingly, the carrier portion 20 and the housing 2 are combined so as to be relatively rotatable about the rotation axis O. As shown in FIG.

In addition, the pair of main bearings 21 are arranged separately in the axial direction so as to sandwich the first swing gear 50 and the second swing gear 60 . In addition, illustration of the main bearing 21 is omitted in FIG. 1 .

The carrier portion 20 of the present embodiment includes a first carrier portion 70 and a second carrier portion 80 disposed on the rear side of the first carrier portion 70 .

The first carrier portion 70 is an output member called, for example, a shaft, and is provided with: a disc-shaped base plate portion 71; 80 extension).

Part of the substrate portion 71 protrudes forward with respect to the housing 2 . A first central through-hole 73 penetrating the substrate portion 71 in the axial direction is formed coaxially with the rotation axis O at the center portion of the substrate portion 71 . Furthermore, three first crank holes 74 that are opened on the rear side are formed in the base plate portion 71 . The first crank holes 74 are arranged at equal intervals in the circumferential direction around the rotation axis O.

In addition, the first crank hole 74 may be formed so as to penetrate the base plate portion 71 in the axial direction.

The pillar part 72 is integrally formed with the board|substrate part 71, and is formed so that it may extend linearly toward the rear, for example. Three pillar portions 72 of the present embodiment are arranged at equal intervals in the circumferential direction around the rotation axis O. As shown in FIG. At this time, the three pillar portions 72 are formed such that the pillar portions 72 and the crankshaft 30 are alternately arranged in the circumferential direction.

The second carrier portion 80 is, for example, a member called a holding flange, and is formed in a disc shape. The second carrier portion 80 is disposed behind the first carrier portion 70 by sandwiching the first swing gear 50 and the second swing gear 60 .

A second central through-hole 81 penetrating the second carrier portion 80 in the axial direction is formed coaxially with the rotation axis O at the central portion of the second carrier portion 80 . Furthermore, three second crank holes 82 penetrating through the second carrier portion 80 in the axial direction are formed in the second carrier portion 80 . The second crank holes 82 are arranged at equal intervals in the circumferential direction around the rotation axis O.

In addition, the second crank holes 82 are formed so as to face the first crank holes 74 formed in the first carrier portion 70 in the axial direction.

The second carrier portion 80 configured as described above is fixed to the pillar portion 72 by bolts 83 in a state of being in contact with the rear end surface of the pillar portion 72 . Thus, the first carrier portion 70 and the second carrier portion 80 are integrated via the pillar portion 72 .

In addition, an axial gap is ensured between the base plate portion 71 of the first carrier portion 70 and the second carrier portion 80 . The first swing gear 50 and the second swing gear 60 are arranged using this gap.

In addition, a pair of main bearings 21 are disposed between the outer peripheral surface of the base plate portion 71 of the first carrier portion 70 and the inner peripheral surface of the housing body portion 10 and between the outer peripheral surface of the second carrier portion 80 and the housing body portion 10 . between the inner peripheral surfaces.

Furthermore, an annular step portion 15 dented outward in the radial direction is formed on the inner peripheral surface of the front end portion of the case main body portion 10 . An annular oil seal 16 is incorporated in the stepped portion 15 .

The oil seal 16 is in close contact with a portion of the outer peripheral surface of the base plate portion 71 of the first carrier portion 70 located radially inward of the stepped portion 15 . The oil seal 16 allows the relative rotation between the first carrier portion 70 and the case main body 10 and ensures the sealing performance between the first carrier portion 70 and the case main body 10 .

The second arm R2 constituting a plurality of arms of the articulated robot as an example of an external member is attached to the first carrier portion 70 configured as described above. For example, the second arm R2 is fixed by a threaded hole or the like formed in the front end surface of the first carrier portion 70 .

Therefore, the speed reducer 1 is combined with the articulated robot by attaching the first arm R1 to the casing 2 and the second arm R2 to the first carrier portion 70 .

(internal tooth pin)

As shown in FIG. 2 , a large number of pin grooves 17 are formed on the inner peripheral surface of the case main body 10 .

The pin groove 17 is formed at least in a portion of the inner peripheral surface of the case main body 10 that faces the first swing gear 50 and the second swing gear 60 in the radial direction. The pin groove 17 is formed to extend in the axial direction and to have a semicircular cross-sectional shape in a cross-section perpendicular to the axial direction. Furthermore, the pin grooves 17 are arranged at equal intervals in the circumferential direction.

A cylindrical internal tooth pin 18 is rotatably accommodated in each pin groove 17 . Thereby, the inner tooth pin 18 is arranged so as to face the outer peripheral surfaces of the first swing gear 50 and the second swing gear 60 . Therefore, the first external teeth 51 to be described later of the first swing gear 50 and the second external teeth 61 to be described later of the second swing gear 60 can mesh with the internal tooth pins 18 .

(crankshaft)

As shown in FIG. 2 , the three crankshafts 30 are arranged at equal intervals in the circumferential direction around the rotation axis O as described above. Each crankshaft 30 is rotatably supported by a first crank bearing 90 and a second crank bearing 91 with respect to the carrier portion 20 .

The first crank bearing 90 is mounted inside the first crank hole 74 formed in the base plate portion 71 of the first carrier portion 70 . The second crank bearing 91 is attached inside the second crank hole 82 formed in the second carrier portion 80 .

Thus, the crankshaft 30 is rotatably supported by the carrier portion 20 (the first carrier portion 70 and the second carrier portion 80 ).

Each crankshaft 30 has a shaft main body 32 extending in the axial direction and an eccentric portion 31 integrally formed with the shaft main body 32 . The eccentric portion 31 has a first eccentric portion 33 and a second eccentric portion 34 corresponding to the first swing gear 50 and the second swing gear 60 .

The first eccentric portion 33 and the second eccentric portion 34 are arranged in parallel in the axial direction between portions of the shaft main body 32 supported by the first crank bearing 90 and the second crank bearing 91 . The first eccentric portion 33 and the second eccentric portion 34 are each formed in a cylindrical shape. Both the first eccentric portion 33 and the second eccentric portion 34 are formed so as to protrude outward in the radial direction from the shaft main body 32 while being eccentric with respect to the shaft center of the shaft main body 32 .

Furthermore, the first eccentric portion 33 and the second eccentric portion 34 are each eccentric by a predetermined amount of eccentricity with respect to the shaft center of the shaft main body 32 , and are disposed so as to have a phase difference with each other by a predetermined angle.

The shaft main body 32 is formed so as to protrude rearward with respect to the rear end surface (end surface of this invention) 80a of the 2nd carrier part 80 facing rearward. Furthermore, a fitted portion 35 to which the transmission gear 36 is attached is provided at the rear end portion of the shaft main body 32 protruding rearward with respect to the rear end surface 80 a of the second carrier portion 80 .

As shown in FIGS. 1 and 2 , the transmission gear 36 is integrated with the crankshaft 30 by being attached to the fitted portion 35 . Thus, the crankshaft 30 integrally rotates with the rotation of the transmission gear 36 . Furthermore, the transmission gear 36 meshes with the input gear 5 formed on the input shaft 4 . Accordingly, each transmission gear 36 rotates in a direction opposite to that of the input shaft 4 as the input shaft 4 rotates. Therefore, the three crankshafts 30 can be synchronously rotated in the same direction by the rotation of the input shaft 4 .

In this manner, in the present embodiment, the speed reducer 1 having a so-called reverse assembly structure is provided in which the crankshaft 30 is combined such that the transmission gear 36 is positioned behind the second carrier portion 80 . Moreover, the rear end surface 80a of the 2nd carrier part 80 is set as the end surface which opposes the transmission gear 36 in the axial direction.

(swing gear)

As shown in FIG. 2 , the first rocking gear 50 is attached to the first eccentric portion 33 of each crankshaft 30 via a first roller bearing 92 . When the first eccentric portion 33 rotates eccentrically with the rotation of each crankshaft 30 , the first oscillating gear 50 oscillates while meshing with the internal gear pin 18 in conjunction with the eccentric rotation.

The first swing gear 50 has: first external teeth 51 ; a central through hole 52 ; a plurality of (for example, three) first eccentric portion through holes 53 ; and a plurality of (for example, three) first relief holes 54 .

The first external teeth 51 are formed on the outer peripheral surface of the first rocking gear 50 in a smoothly continuous wave shape over the entire circumference, and are in contact with the plurality of internal tooth pins 18 in a meshed state. In addition, the number of teeth of the first external teeth 51 is slightly smaller than that of the internal tooth pins 18 (for example, one or two fewer).

The central through hole 52 is formed in the central portion of the first swing gear 50 so as to pass through the first swing gear 50 in the axial direction.

The first eccentric portion through-holes 53 are formed so as to be arranged at equal intervals in the circumferential direction around the center through-hole 52 . The first eccentric portions 33 of the respective crankshafts 30 pass through the respective first eccentric portion penetration holes 53 via the first roller bearings 92 . Therefore, the first roller bearing 92 is disposed between the inner wall of the first eccentric portion through hole 53 and the first eccentric portion 33 .

The first escape holes 54 are formed to be arranged at equal intervals in the circumferential direction centering on the central through hole 52 . The first escape holes 54 are arranged so as to be located between the first eccentric portion through-holes 53 in the circumferential direction. The pillar portion 72 of the first carrier portion 70 penetrates through each of the first relief holes 54 with a predetermined play. Accordingly, the swinging and rotating operation of the first swinging gear 50 is not hindered by the first relief hole 54 .

The second swing gear 60 is configured in the same manner as the first swing gear 50 described above, and thus detailed description thereof will be omitted.

That is, the second oscillating gear 60 is attached to the second eccentric portion 34 of each crankshaft 30 via the second roller bearing 93 , and oscillatingly rotates while meshing with the inner gear pin 18 in conjunction with the eccentric rotation of the second eccentric portion 34 . Furthermore, the second swing gear 60 has second external teeth 61 , a central through hole 62 , a plurality of (for example, three) second eccentric portion through holes 63 , and a plurality of (for example, three) second escape holes 64 .

(Strengthening Department)

The reinforcement part 100 for reinforcing the thickness of the 2nd carrier part 80 along the axial direction is formed in the speed reducer 1 comprised as mentioned above.

As shown in FIGS. 1 and 2 , the reinforcing portion 100 is formed to protrude rearward (outward) from the rear end surface 80 a of the second carrier portion 80 . In the illustrated example, the reinforcement part 100 is formed integrally with the rear end surface 80a of the second carrier part 80, but it is not limited to this case, and may be formed separately from the second carrier part 80, for example. On the top, it is integrally combined with the second carrier part 80 .

The protruding length of the reinforcing portion 100 is not particularly limited. In the illustrated example, the reinforcing portion 100 has a protruding length such that the rear end edge is located forward of the rear end surface of the transmission gear 36 . However, it is not limited to this case, and the rear end edge of the reinforcement part 100 may protrude to the same extent as the rear end surface of the transmission gear 36, or the rear end edge of the reinforcement part 100 may protrude rearward with respect to the transmission gear 36. Highlight length.

The reinforcement part 100 of the present embodiment includes an annular reinforcement ring part 101 extending in the circumferential direction and a reinforcement plate 102 formed integrally with the reinforcement ring part 101 .

In addition, in FIGS. 1 and 2 , phantom lines are appropriately used so that the reinforcing ring portion 101 and the reinforcing plate 102 can be clearly seen.

The reinforcement ring portion 101 is formed to surround the three transmission gears 36 respectively attached to the crankshaft 30 from the radially outer side. The reinforcement plate 102 is formed to extend radially inward from the reinforcement ring portion 101 so as to enter between the circumferentially adjacent transmission gears 36 . Therefore, three reinforcing plates 102 are arranged at equal intervals in the circumferential direction.

At this time, the reinforcing plate 102 extends radially inward while extending the outer edge portion smoothly along the external shape of the transmission gear 36 . Thus, the reinforcement plate 102 is formed to surround the transmission gear 36 . Therefore, the three transmission gears 36 are arranged so as to be accommodated between the reinforcement plates 102 adjacent to each other in the circumferential direction.

The reinforcing portion 100 configured as described above is formed such that the thinnest portion along the radial direction has a thickness of at least 1 mm or more.

In the present embodiment, the portion of the reinforcement ring portion 101 located on the opposite side to the rotation axis O in the radial direction across the transmission gear 36 is set as the thinnest portion 103 having the thinnest thickness. In addition, the thin portion 103 corresponds to a portion of the reinforcement ring portion 101 located between the reinforcement plates 102 adjacent in the circumferential direction. Furthermore, the reinforcing ring portion 101 is formed such that the thin portion 103 has a thickness H of at least 1 mm or more.

(The role of the reducer)

Next, the operation of the speed reducer 1 configured as described above will be described.

According to the speed reducer 1 of this embodiment, the rotation input from the drive motor M can be decelerated by the speed reduction part 3, and can be output.

Specifically, as shown in FIGS. 1 and 2 , the input shaft 4 rotates as the drive motor M is driven, whereby the crankshafts 30 can be synchronously rotated in the same direction via the input gear 5 and the transmission gear 36 . As a result, the first eccentric portion 33 and the second eccentric portion 34 of each crankshaft 30 can be rotated, and therefore, the first swing gear 50 and the second swing gear 60 can be swing-rotated in the same direction. At this time, the first external teeth 51 of the first swing gear 50 and the second external teeth 61 of the second swing gear 60 are in contact with the internal tooth pins 18 held by the case main body 10 so as to mesh with the internal teeth pins 18 . .

In addition, the number of teeth of the first external teeth 51 and the second external teeth 61 is formed slightly less than the number of the internal tooth pins 18, therefore, the first swinging gear 50 and the second swinging gear 60 swing and rotate once, and the first swinging The gear 50 and the second swing gear 60 receive a reaction force in the rotation direction from the inner tooth pin 18, and rotate by a predetermined tooth pitch in a direction opposite to the swing rotation direction. At this time, since the carrier portion 20 allows the first swing gear 50 and the second swing gear 60 to swing and rotate while restraining the autorotation, the autorotation component can be transmitted as the revolution of the carrier portion 20 . Accordingly, it is possible to output via the carrier portion 20 with the rotation of the drive motor M decelerated.

Therefore, for example, when the housing 2 is fixed, the decelerated rotation can be output to the articulated robot via the carrier portion 20 . Specifically, since the first arm R1 of the articulated robot is attached to the housing 2 and the second arm R2 of the articulated robot is attached to the first carrier portion 70, the rotation of the drive motor M can be reduced at a reduced speed. The state is transferred to the second arm R2. Accordingly, the first arm R1 and the second arm R2 can be relatively displaced via the speed reducer 1 .

In particular, since the transmission gear 36 is arranged outside the second carrier portion 80 , a so-called reverse assembly structure, the input shaft 4 can be positioned outside the second carrier portion 80 via the input shaft 4 . The rotation of the drive motor M is easily transmitted to the plurality of transmission gears 36 . Therefore, it is possible to assemble the speed reducer 1 according to the application.

Even if the transmission gear 36 is disposed outside the second carrier portion 80 in this way, the rear end surface 80 a of the second carrier portion 80 is formed with a reinforcing portion 100 protruding outward. Therefore, the thickness along the axial direction can be thickened in accordance with the formation of the reinforcing portion 100 , and the rigidity of the second carrier portion 80 itself can be increased to increase the rigidity.

Therefore, troubles such as deformation of the second carrier portion 80 due to stress transmitted from, for example, the crankshaft 30 to the second carrier portion 80 through the main bearing 21 are less likely to occur. Therefore, it is possible to provide the speed reducer 1 with improved operational reliability.

Furthermore, since the rigidity of the second carrier portion 80 can be increased, it is possible to appropriately apply a preload to the main bearing 21 while suppressing deformation of the second carrier portion 80 . As a result, the reliability of operation and the like can be further improved.

As described above, according to the speed reducer 1 of the present embodiment, the reinforcement part 100 is provided, so that the rigidity of the carrier part 20 (the second carrier part 80 ) can be improved, and the reliability of the operation can be improved. Sexual reducer 1.

In addition, in the present embodiment, not only the reinforcing portion 100 protrudes rearward from the rear end portion of the second carrier portion 80 , but also the three transmission gears 36 are surrounded from the radially outer side by the annular reinforcing ring portion 101 . In particular, the reinforcing ring portion 101 can be formed on the entire circumference of the second carrier portion 80. Therefore, in addition to ensuring the thickness of the second carrier portion 80, it is also possible to make the second carrier portion 80 less likely to be strained, Undue deformation such as warping.

Furthermore, since the reinforcing part 100 has the reinforcing plate 102, the second carrier part 80 can be made thicker in a wider range, and the rigidity can be effectively improved. Furthermore, the reinforcing plate 102 is formed to surround the transmission gear 36 . Thus, the reinforcing plate 102 can be formed over as wide a range as possible without hindering the movement of the transmission gear 36 . Furthermore, the reinforcement plate 102 makes it easy to protect the transmission gear 36 and avoid unnecessary contact with the transmission gear 36 from the outside, for example.

Furthermore, since the thin portion 103 in the reinforcing portion 100 has a thickness H of at least 1 mm or more, it can properly function as the reinforcing portion 100 , and the above-mentioned effects can be achieved more reliably.

(second embodiment)

Next, a second embodiment of the speed reducer of the present invention will be described with reference to the drawings. In addition, in this second embodiment, the same reference numerals are assigned to the same components as those in the first embodiment, and description thereof will be omitted.

In the first embodiment, the so-called solid type speed reducer 1 in which the input shaft 4 is arranged coaxially with the rotation axis O has been described as an example. A so-called hollow type speed reducer that is partially penetrated in the axial direction.

As shown in FIG. 3 , compared with the first embodiment, the first central through hole 73 of the first carrier portion 70 of the speed reducer 110 of the present embodiment, the second central through hole 81 of the second carrier portion 80 , The diameters of the central through hole 52 of the first swing gear 50 and the central through hole 62 of the second swing gear 60 are formed large.

Furthermore, the insides of the first central through-hole 73 , the second central through-hole 81 , and the central through-holes 52 and 62 function as a hollow space R penetrating in the axial direction.

In addition, corresponding to the fact that the diameters of the first central through hole 73, the second central through hole 81, and the central through holes 52 and 62 are formed larger, for example, the crankshaft 30, the pillar portion 72, and the like are arranged radially closer to the first embodiment than in the first embodiment. position on the outer side, and the size is formed smaller as required.

In addition, in the present embodiment, the input shaft 4 is arranged at a position deviated from the rotation axis O in the radial direction so as not to close the hollow space R of the speed reducer 110 . Specifically, the input shaft 4 is disposed on the rear side of the transmission gear 36 with a slight gap therebetween. Accordingly, the transmission gear 36 and the input gear 5 are arranged to be aligned in the axial direction.

Therefore, the speed reducer 110 of the present embodiment includes an intermediate gear 120 that transmits rotation from the input gear 5 to each transmission gear 36 .

The intermediate gear 120 includes: an intermediate cylinder 121 formed in a cylindrical shape around the rotation axis O; and an annular intermediate ring 122 protruding radially outward from the outer peripheral surface of the intermediate cylinder 121 so as The entire circumference of the intermediate cylinder 121 is formed so as to extend in the circumferential direction.

The intermediate cylinder 121 is arranged such that the front end portion of the intermediate cylinder 121 enters the housing recess 130 formed on the rear end surface 80 a of the second carrier portion 80 from behind.

The housing recess 130 is formed in a central portion of the rear end surface 80a of the second carrier portion 80 so as to be recessed forward. The housing recess 130 is formed in a circular shape when viewed from the rear, and is formed so as to open at the rear. Furthermore, the inner diameter of the storage recess 130 is formed larger than the inner diameter of the second central through hole 81 formed in the second carrier portion 80 , and the storage recess 130 is connected to the second central through hole 81 .

The front end portion of the intermediate cylinder 121 is arranged so as to be located inside the above-mentioned storage recess 130 . Furthermore, an intermediate bearing 131 that supports the intermediate gear 120 so as to be rotatable about the rotation axis O is provided between the front end portion of the intermediate cylinder 121 and the housing recess 130 . Accordingly, the entire intermediate gear 120 is supported so as to be relatively rotatable about the rotation axis O with respect to the second carrier portion 80 .

In addition, the inner diameter of the intermediate cylinder 121 is set to be equal to the inner diameter of the second central through hole 81 formed in the second carrier portion 80 . Therefore, the inner space of the intermediate cylinder 121 also functions as the hollow space R. As shown in FIG.

The intermediate ring 122 is tightly fitted to, for example, the outer peripheral surface of the intermediate cylinder 121 in a state located behind the transmission gear 36 . Thus, the intermediate cylinder 121 and the intermediate ring 122 are combined into one body. However, the intermediate ring 122 does not need to be formed separately from the intermediate cylinder 121 , for example, the intermediate cylinder 121 and the intermediate ring 122 may also be integrally formed.

First intermediate teeth 123 that mesh with the transmission gear 36 over the entire circumference of the intermediate cylinder 121 are formed on the outer peripheral surface of the portion of the intermediate cylinder 121 located between the intermediate bearing 131 and the intermediate ring 122 . Further, second intermediate teeth 124 that mesh with the transmission gear 36 over the entire circumference are formed on the outer peripheral portion of the intermediate ring 122 .

As a result, the intermediate gear 120 rotates with the rotation of the input shaft 4 and can transmit the torque from the input shaft 4 to the transmission gear 36 . Therefore, the rotation from the drive motor M can be transmitted to the crankshaft 30 via the input shaft 4 , the intermediate gear 120 , and the transmission gear 36 .

In addition, in the speed reducer 110 of the present embodiment, the reinforcement portion 100 including the reinforcement ring portion 101 and the reinforcement plate 102 is formed on the rear end surface 80 a of the second carrier portion 80 as in the first embodiment. Since the reinforcement part 100 is the same as that of the first embodiment, detailed description thereof will be omitted.

(The role of the reducer)

Even the speed reducer 110 of the present embodiment can exhibit the same operational effects as those of the speed reducer 1 of the first embodiment.

In particular, since the speed reducer 110 of this embodiment is a hollow structure type, various cables, components, etc. associated with the speed reducer 110 or an articulated robot, for example, can be penetrated using the hollow space R. Therefore, the speed reducer 110 can be easily assembled.

Moreover, it is a hollow structure type, so, for example, on the basis that the second central through hole 81 of the second carrier part 80 is formed larger, the receiving recessed part 130 for the intermediate bearing 131 is formed in the second carrier part 80 etc., therefore, there is a tendency that the rigidity of the second carrier portion 80 tends to decrease.

However, since the reinforcement part 100 is formed in the 2nd carrier part 80, the rigidity reduction of the 2nd carrier part 80 can be suppressed. Therefore, it can be set as the hollow structure type speed reducer 110 which improves the reliability of operation.

As mentioned above, although embodiment of this invention was described, these embodiment is provided as an example, and it does not intend that the range of the invention is limited. The embodiment can be implemented in other various forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. Embodiments and modifications thereof include, for example, items that can be easily conceived by those skilled in the art, items that are substantially the same, items in an equivalent range, and the like.

For example, in each of the above-mentioned embodiments, the case where the reinforcing part 100 includes the reinforcing ring part 101 and the reinforcing plate 102 has been described as an example, but it is not limited to this case. For example, the reinforcing portion 100 may be configured to include only the reinforcing ring portion 101 and not include the reinforcing plate 102 .

Furthermore, as the reinforcing portion 100, it may be formed so as to extend from the rear end surface 80a of the second carrier portion 80 toward the rear (transmission gear 36 side), or may be formed as ribs arranged radially around the rotation axis O, for example. shape. In this way, the reinforcing portion 100 may be appropriately changed in consideration of the use of the speed reducer, the number and arrangement of the transmission gears 36 , and the like.

Furthermore, in the solid type speed reducer 1 according to the first embodiment, the case where three crankshafts 30 are arranged at equal intervals in the circumferential direction around the axis of rotation O has been described as an example, but it is not limited to The situation. A so-called center crank type speed reducer in which, for example, one crankshaft 30 is arranged coaxially with the rotation axis O may also be employed. In this case, for example, the input shaft 4 may be arranged at an eccentric position with respect to the rotation axis O, and the input gear 5 may be meshed with the transmission gear 36 . Even in this case, the same operation and effect can be achieved.

In addition, in the embodiments disclosed in this specification, a member composed of a plurality of objects may be integrated, and conversely, a member composed of a single object may be divided into a plurality of objects. Regardless of whether it is integrated or not, it may be configured in such a manner that the purpose of the utility model can be achieved.

Claims (5)

1. A speed reducer is characterized in that a speed reducer body is provided,

it is provided with:

a housing which is rotatably disposed around a rotation axis; and

a reduction unit having a gear frame portion disposed inside the housing so as to be relatively rotatable about the rotation axis, and configured to reduce a rotation input from the drive unit and output the rotation,

the speed reduction unit includes:

a crankshaft having an eccentric portion eccentric with respect to the rotation axis and rotating with rotation from the driving portion; and

a swing gear that swings about the rotation axis in accordance with rotation of the eccentric portion,

the gear carrier portion cooperates with the oscillating gear,

a transmission gear is attached to the crankshaft, is disposed outside the gear frame portion along the rotation axis, and transmits rotation from the driving portion,

the gear frame portion has a reinforcing portion formed to protrude outward along the rotation axis from an end surface of the gear frame portion that faces the transmission gear in the rotation axis direction.

2. Decelerator according to claim 1,

a plurality of the crankshafts are arranged at intervals in a circumferential direction that revolves around the rotation axis,

the reinforcing portion includes an annular reinforcing ring portion extending in the circumferential direction so as to surround the transmission gears attached to the plurality of crankshafts, respectively, from an outer side in a radial direction of the housing.

3. Decelerator according to claim 2,

the reinforcing portion includes a reinforcing plate that extends from the reinforcing ring portion toward the inside in the radial direction so as to enter between the transmission gears adjacent in the circumferential direction, and that is formed integrally with the reinforcing ring portion,

the reinforcing plate is formed so as to surround the periphery of the transmission gear.

4. Decelerator according to any one of claims 1 to 3,

the reinforcing portion is formed such that the thinnest portion has a wall thickness of at least 1mm or more.

5. A speed reducer is characterized in that a speed reducer body is provided,

the speed reducer is provided with:

a housing which is rotatably disposed around a rotation axis; and

a speed reduction unit having a gear frame unit disposed inside the housing so as to be relatively rotatable around the rotation axis, and configured to reduce a rotation input from the drive unit and output the rotation,

the speed reduction unit includes:

a crankshaft having an eccentric portion eccentric with respect to the rotation axis, rotatably supported by the gear frame portion, and rotated in accordance with rotation from the driving portion; and

a swing gear that swings and rotates about the rotation axis in accordance with rotation of the eccentric portion,

the gear frame portion cooperates with the oscillating gear so as to allow oscillating rotation of the oscillating gear and restrict autorotation rotation of the oscillating gear,

the gear frame portion has:

a 1 st gear frame part; and

a 2 nd gear carrier part which is arranged to be aligned with the 1 st gear carrier part on the rotation axis and is combined with the 1 st gear carrier part with the swing gear interposed therebetween,

a plurality of the crankshafts are arranged at intervals in a circumferential direction revolving around the rotation axis about the rotation axis,

a transmission gear is attached to each of the crankshafts, is disposed outside the 2 nd gear frame portion along the rotation axis, and transmits rotation from the driving portion,

the 2 nd gear frame portion has a reinforcing portion formed to protrude outward along the rotation axis from an end surface of the 2 nd gear frame portion facing the transmission gear in the rotation axis direction,

the reinforcement unit includes:

an annular reinforcing ring portion extending along the circumferential direction so as to surround the transmission gear from an outer side in a radial direction of the housing; and

a reinforcing plate that extends from the reinforcing ring portion toward the radially inner side so as to enter between the transmission gears adjacent in the circumferential direction and is formed integrally with the reinforcing ring portion, the reinforcing plate being formed so as to surround the periphery of the transmission gears.

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