Planetary gear speed reducing mechanism

Abstract

The present invention provides a planetary gear reduction mechanism capable of driving an object to be driven with good precision. The bracket (60) is provided with a first support shaft fixing hole and a second support shaft fixing hole (64a, 64b) for fixing a support shaft (52), the support shaft (52) rotatably supports the planetary gear (50), and the coupling (70) is fixed to the bracket (60) through a fixing pin (73) fixed to the second support shaft fixing hole (64b). As a result, the coupling (70) can be accurately fixed to the bracket (60) formed with high machining accuracy. As a result, it is possible to realize a planetary gear reduction mechanism (10) that can drive a drive mechanism or the like of a robot, which is an object to be driven, with good precision.

Description

Technical Field

[0001] The invention relates to a planetary gear reduction mechanism with a plurality of gears. Background Art

[0002] For example, Patent Document 1 describes a planetary gear reducer in which a planetary gear mechanism including a sun gear, a planetary gear, a carrier, and an internal gear is arranged in two stages in an axially overlapping manner. As a result, the rotation speed of a motor shaft as an input side is reduced, and a high-torque rotational force is output from an output shaft as an output side.

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2003-172411 Summary of the invention

[0006] [Problems to be solved by the invention]

[0007] In the technology described in Patent Document 1, an output shaft is integrally provided at the rotation center of the bracket, but a coupling is required between the output shaft and the driven object in order to connect the output shaft to the driven object in a manner capable of transmitting power. Furthermore, if the coupling is mounted with low precision relative to the output shaft, shaking occurs between the coupling and the output shaft, and there is a problem that the driven object cannot be driven with good precision.

[0008] An object of the present invention is to provide a planetary gear reduction mechanism capable of driving a driven object with high accuracy.

[0009] [Technical means to solve the problem]

[0010] In one form of the present invention, the planetary gear reduction mechanism has multiple gears and includes: an input-side rotating body connected to a driving source in a manner capable of transmitting power; a sun gear disposed on the input-side rotating body; an internal gear arranged on the radially outer side of the sun gear; planetary gears arranged between the sun gear and the internal gear; a planetary carrier supporting the planetary gears so that they can rotate freely; and an output-side rotating body fixed to the planetary carrier to drive a driven object, the planetary carrier being provided with a support shaft fixing hole for fixing a support shaft, the support shaft supporting the planetary gears so that they can rotate freely, and the output-side rotating body being fixed to the planetary carrier by a fixing member fixed to the support shaft fixing hole.

[0011] [Effects of the Invention]

[0012] According to the present invention, a planetary gear reduction mechanism capable of driving a driven object with high accuracy can be realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a perspective view of the planetary gear reduction mechanism viewed from the output side.

[0014] Figure 2 This is a perspective view of the planetary gear reduction mechanism viewed from the input side.

[0015] Figure 3 Yes means Figure 1 A cross-sectional view of the internal structure of a planetary gear reduction mechanism.

[0016] Figure 4 This is a three-dimensional diagram showing the pinion gear as a single unit.

[0017] Figure 5 This is a three-dimensional diagram showing an internal gear as a single body.

[0018] Figure 6 It is a three-dimensional diagram showing three helical gears.

[0019] Figure 7 This is a three-dimensional diagram showing the bracket as a single body.

[0020] Figure 8 It is a three-dimensional diagram showing the assembly process of the bracket assembly.

[0021] Fig. 9 This is a perspective view showing the assembly process of the internal gear relative to the carrier assembly.

[0022] Fig.10 It is a perspective view showing the assembly process of the housing body and the ring member.

[0023] Fig.11 This is a perspective view showing the assembly process of the pinion gear and the play adjustment member.

[0024] Fig.12 This is a perspective view showing the assembly process of the coupling to the bracket.

[0025] Fig.13 The planetary gear reduction mechanism of the second embodiment is shown in FIG. Figure 3 The corresponding cross-section diagram.

[0026] [Explanation of Symbols]

[0027] 10: Planetary gear reduction mechanism

[0028] 20: Shell

[0029] 21: Shell body

[0030] 21a: Cylindrical part

[0031] 21b: First flange portion

[0032] 21c: Through hole

[0033] 21d: Second flange portion

[0034] 21e: threaded hole

[0035] 22: Ring component

[0036] 22a: Ring body

[0037] 22b: Third flange portion

[0038] 22c: Internal thread hole

[0039] 30: Pinion (sun gear)

[0040] 31: Input shaft (input side rotating body)

[0041] 31a: Bearing installation part

[0042] 31b: Support steps

[0043] 32: Helical teeth (one tooth)

[0044] 40: Internal gear (internal gear)

[0045] 41: Tubular body

[0046] 42: Fourth flange portion

[0047] 42a: Through hole

[0048] 43: Gear forming part

[0049] 43a: Internal teeth

[0050] 50: Planetary gear (planetary gear)

[0051] 51: Gear forming part

[0052] 51a: Engagement recess

[0053] 52: Support shaft

[0054] 60: Bracket (planet carrier)

[0055] 61: Tubular main body

[0056] 62: Gear support

[0057] 62a: Communication hole

[0058] 63a: First base

[0059] 63b: Second base

[0060] 64a: First support shaft fixing hole (support shaft fixing hole)

[0061] 64b: Second support shaft fixing hole (support shaft fixing hole)

[0062] 65: Input side cylinder

[0063] 65a: Through hole

[0064] 65b: threaded hole

[0065] 66: Output side cylinder

[0066] 66a: Through hole

[0067] 66b: Internal thread

[0068] 67: Cover member

[0069] 67a: Screw insertion hole

[0070] 68: Shake adjustment component

[0071] 70: Coupling (output side rotating body)

[0072] 71: Fixed main body

[0073] 71a: Fixing hole (fixing hole for fixing member)

[0074] 71b: Screw insertion hole

[0075] 72: Output shaft

[0076] 73: Fixing pin (fixing member)

[0077] 73a: Conical part

[0078] 100: Planetary gear reduction mechanism

[0079] 110: Coupling (output side rotating body)

[0080] 111: Output shaft

[0081] BB1: First ball bearing

[0082] BB2: Second ball bearing

[0083] BB3: Third ball bearing

[0084] BB4: Fourth ball bearing

[0085] BB5: Fifth ball bearing

[0086] BB6: Sixth ball bearing

[0087] CA: Bracket assembly

[0088] P: Positioning convex part

[0089] SD: Reducer

[0090] ST1: First step

[0091] ST2: Second step

[0092] WS1: First Washer

[0093] WS2: Second washer

[0094] WS3: Third washer DETAILED DESCRIPTION

[0095] [Implementation Method 1]

[0096] Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to the drawings.

[0097] Figure 1 1 shows a perspective view of the planetary gear reduction mechanism viewed from the output side. Figure 2 The following is a perspective view of the planetary gear reduction mechanism viewed from the input side. Figure 3 Shows the representation Figure 1 A cross-sectional view of the internal structure of the planetary gear reduction mechanism. Figure 4 A perspective view showing a pinion gear as a single body is shown. Figure 5 A perspective view showing an internal gear as a single body is shown. Figure 6 A perspective view showing three helical gears is shown, Figure 7 A perspective view showing the bracket as a single body is shown.

[0098] [Overview of planetary gear reduction mechanism]

[0099] Figures 1 to 3 The planetary gear reduction mechanism 10 shown is used, for example, for driving a joint of a robot. Furthermore, an electric motor (not shown) as a driving source is provided on the input side (lower side in the figure) of the planetary gear reduction mechanism 10 so as to be able to transmit power, and a driving mechanism (not shown) of a robot as a driven object is provided on the output side (upper side in the figure) of the planetary gear reduction mechanism 10 so as to be able to transmit power.

[0100] More specifically, the input shaft 31 of the planetary gear reduction mechanism 10 is rotated by the electric motor, and the output shaft 72 of the planetary gear reduction mechanism 10 drives the driving mechanism of the robot. In addition, the planetary gear reduction mechanism 10 decelerates the rotation of the input shaft 31 to increase the torque, and outputs the rotational force obtained by the increase in torque from the output shaft 72.

[0101] Thus, even if the driving source is a small electric motor, the planetary gear reduction mechanism 10 can transmit a large driving torque to the driving mechanism of the robot. Thus, the electric motor can be miniaturized and can be easily installed inside the arm of the robot with a small installation space.

[0102] Furthermore, the planetary gear reduction mechanism 10 of this embodiment is not limited to the use in driving joints of robots, but may also be applied to small-sized driving systems mounted on vehicles such as automobiles, such as power sliding door devices and power window devices.

[0103] [case]

[0104] The planetary gear reduction mechanism 10 includes a housing 20 that forms the outer contour of the planetary gear reduction mechanism 10. The housing 20 includes: a housing body 21 formed in a substantially cylindrical shape; and a ring member 22, which is installed on one axial side (lower side in the figure) of the housing body 21 and is formed in an annular shape. In addition, the housing body 21 and the ring member 22 are both made of aluminum, thereby achieving the overall weight reduction of the planetary gear reduction mechanism 10.

[0105] The housing body 21 includes: a cylindrical portion 21a extending in the axial direction of the planetary gear reduction mechanism 10; and a total of eight first flange portions 21b, which are integrally provided on one axial side of the cylindrical portion 21a and protrude radially outward of the cylindrical portion 21a. In addition, each of the total of eight first flange portions 21b is provided with an insertion hole 21c for inserting a fixing bolt (not shown).

[0106] On the other hand, an annular second flange portion 21d is integrally provided on the other axial side (upper side in the figure) of the cylindrical portion 21a so as to protrude radially inwardly of the cylindrical portion 21a. Furthermore, an outer ring (outer race) of the first ball bearing BB1 is mounted radially inwardly of the second flange portion 21d. In addition, one axial side (lower side in the figure) of the second flange portion 21d supports the other axial side (upper side in the figure) of the ring gear 40.

[0107] In this manner, the second flange portion 21 d of the case body 21 has a function of supporting both the first ball bearing BB1 and the ring gear 40 .

[0108] Here, the first ball bearing BB1 rotatably supports the other axial side (upper side in the figure) of the bracket 60. Specifically, the inner ring (inner race) of the first ball bearing BB1 is installed on the output side cylindrical portion 66 (see Figure 7 )'s outer periphery.

[0109] In addition, a plurality of threaded holes 21e are provided on the other axial side (upper side in the figure) of the second flange portion 21d. Fixing screws (not shown) are screwed into these threaded holes 21e, and the fixing screws are used to fix the planetary gear reduction mechanism 10 to a fixing portion (not shown) inside the arm of a robot or the like.

[0110] The ring member 22 includes an annular main body 22a. A total of eight third flange portions 22b are integrally provided on the annular main body 22a in a manner protruding radially outward. These third flange portions 22b are provided corresponding to the first flange portion 21b of the housing main body 21. In addition, each third flange portion 22b is provided with an internal threaded hole 22c for screwing a fixing bolt (not shown).

[0111] In addition, in the axial direction of the housing 20, a total of eight fourth flange portions 42 provided on the ring gear 40 are sandwiched between the first flange portion 21b and the third flange portion 22b forming the housing 20. Thus, the speed reducer SD is accommodated and fixed inside the housing 20 by inserting fixing bolts (not shown) through the insertion holes 21c of the first flange portion 21b and the insertion holes 42a of the fourth flange portion 42 and screwing them into the internal threaded holes 22c of the third flange portion 22b.

[0112] In addition, the outer ring (outer race) of the second ball bearing BB2 is mounted radially inside the ring member 22. That is, the ring member 22 has the function of supporting the second ball bearing BB2 and fixing the ring gear 40 inside the housing 20.

[0113] Here, the second ball bearing BB2 rotatably supports one axial side (lower side in the figure) of the bracket 60. Specifically, the inner ring (inner race) of the second ball bearing BB2 is mounted on the input side cylindrical portion 65 (see Figure 7 )'s outer periphery.

[0114] In addition, a total of four positioning protrusions P (see FIG. 1 ) are integrally provided on the other axial side (upper side in the figure) of the ring member 22. Fig.10 ). These positioning protrusions P protrude toward the ring gear 40 in the axial direction of the ring member 22 and engage with the engaging recesses (not shown) of the ring gear 40. As a result, the ring member 22 can be easily positioned relative to the ring gear 40 (improvement of assembly performance).

[0115] In addition, the first ball bearing BB1 and the second ball bearing BB2 that support the bracket 60 on both sides in the axial direction are respectively made of ball bearings of the same size and specification. In addition, the first ball bearing BB1 and the second ball bearing BB2 are the largest ball bearings provided on the planetary gear reduction mechanism 10.

[0116] [Overview of the reducer]

[0117] like Figures 3 to 7 As shown, the planetary gear reduction mechanism 10 has a plurality of gears. Specifically, the reducer SD accommodated in the housing 20 includes a pinion 30, a ring gear 40, a total of three planetary gears 50, and a carrier 60 that holds these planetary gears 50. That is, the reducer SD is a planetary reducer.

[0118] [Small gear]

[0119] like Figure 3 and Figure 4 As shown, the pinion gear 30 is integrally provided on the other axial side (upper side in the figure) of the input shaft 31. Moreover, the input shaft 31 is connected to the rotating shaft (not shown) of the electric motor as the driving source on one axial side (lower side in the figure) in a manner that can transmit power. Thus, the pinion gear 30 rotates at a predetermined rotational speed in a predetermined rotational direction as the electric motor is driven to rotate.

[0120] The input shaft 31 corresponds to the input-side rotating body in the present invention. The pinion gear 30 corresponds to the sun gear in the present invention.

[0121] The helical teeth 32 are integrally provided on the outer circumference of the pinion gear 30. The axial length of the pinion gear 30 (helical teeth 32) is slightly greater than the axial length of the planetary gear 50. Thus, the helical teeth 32 can mesh with the planetary gear 50 reliably.

[0122] In addition, the spiral tooth 32 corresponds to one tooth in the present invention.

[0123] The spiral teeth 32 are connected in a spiral shape in the axial direction of the pinion gear 30, and only one spiral tooth 32 is provided on the pinion gear 30. That is, the number of teeth of the pinion gear 30 is "1". In addition, the cross-sectional shape of the spiral tooth 32 is substantially semicircular, and the spiral tooth 32 enters (meshes with) the meshing recess 51a of the planetary gear 50 (see Figure 6 ).

[0124] Thus, by setting the number of teeth of the pinion gear 30 to "1", the transmission efficiency of the gear can be improved, and a large reduction ratio can be obtained while being small. Therefore, the electric motor as a driving source can be made smaller and power-saving.

[0125] [Internal gear]

[0126] like Figure 3 and Figure 5As shown, the internal gear 40 is fixed to the radial inner side of the cylindrical portion 21a forming the housing body 21. Specifically, the internal gear 40 is clamped by the housing body 21 and the ring member 22 in the axial direction of the planetary gear reduction mechanism 10. In addition, the internal gear 40 includes: a cylindrical body 41 formed in a substantially cylindrical shape; and a total of 8 fourth flange portions 42, which protrude radially outward from the cylindrical body 41 on one side of the axial direction of the cylindrical body 41.

[0127] The cylindrical body 41 is arranged radially outside the pinion gear 30, and a gear forming portion 43 is provided radially inside the cylindrical body 41. The gear forming portion 43 of the cylindrical body 41 is integrally provided with a plurality of internal teeth 43a having a substantially semicircular cross-sectional shape similar to the helical teeth 32 of the pinion gear 30. Here, the plurality of internal teeth 43a are inclined at a predetermined angle relative to the axial direction of the cylindrical body 41, thereby being able to mesh with the meshing recess 51a of the planetary gear 50 (see Figure 6 ).

[0128] In addition, the ring gear 40 corresponds to the internal gear in the present invention.

[0129] The fourth flange 42 provided on the ring gear 40 corresponds to the first flange 21b of the housing body 21 and the third flange 22b of the ring member 22. The eight fourth flanges 42 each have an insertion hole 42a through which a fixing bolt (not shown) is inserted.

[0130] Thus, the fourth flange portion 42 is sandwiched between the first flange portion 21 b and the third flange portion 22 b , and the ring gear 40 is firmly fixed in both the axial direction and the circumferential direction with respect to the housing 20 without rattling.

[0131] [Planetary gear]

[0132] like Figure 3 and Figure 6 As shown, a total of three planetary gears 50 are arranged between the pinion gear 30 and the ring gear 40 in the radial direction of the planetary gear reduction mechanism 10. Each planetary gear 50 is arranged at equal intervals (120 degree intervals) relative to the circumferential direction of the pinion gear 30 and the ring gear 40, and meshes with both the pinion gear 30 and the ring gear 40.

[0133] In addition, the planetary gear 50 corresponds to the planetary gear in the present invention.

[0134] The planetary gear 50 is formed in a substantially cylindrical shape, and a gear forming portion 51 is provided on the radially outer side thereof. A plurality of meshing recesses 51a are provided in the gear forming portion 51 of the planetary gear 50 in a manner arranged in the circumferential direction thereof. These meshing recesses 51a are inclined at a predetermined angle with respect to the axial direction of the planetary gear 50, so that the helical teeth 32 of the pinion gear 30 and the internal teeth 43a of the internal gear 40 can enter the inside of the meshing recesses 51a and mesh with each other.

[0135] Here, the planetary gear 50 has a meshing recess 51 a that is inclined with respect to the axial direction of the planetary gear 50 , and may also be called a helical gear.

[0136] Therefore, each planetary gear 50 rotates between the pinion gear 30 rotated by an electric motor (not shown) and the ring gear 40 fixed to the housing 20. The meshing recess 51a of the planetary gear 50 is recessed so that its cross-sectional shape is substantially semicircular.

[0137] A third ball bearing BB3 and a fourth ball bearing BB4 are provided on the radial inner side of the planetary gear 50. Specifically, the third ball bearing BB3 is provided on one axial side (lower side in the figure) of the planetary gear 50, and the fourth ball bearing BB4 is provided on the other axial side (upper side in the figure) of the planetary gear 50. Moreover, the outer rings (outer races) of the third ball bearing BB3 and the fourth ball bearing BB4 are installed on the radial inner side of the planetary gear 50.

[0138] The third ball bearing BB3 and the fourth ball bearing BB4 are ball bearings of the same size and specification. In addition, the third ball bearing BB3 and the fourth ball bearing BB4 are smaller ball bearings than the first ball bearing BB1 and the second ball bearing BB2 that rotatably support the bracket 60 .

[0139] A total of three planetary gears 50 are rotatably supported by the support shaft 52. Specifically, in the mounting bracket assembly CA (refer to Fig. 9 ), the support shaft 52 is inserted into the inner ring (inner race) of the third ball bearing BB3 and the fourth ball bearing BB4 installed on the planetary gear 50. Moreover, the axial sides of the support shaft 52 are respectively fixed to the first support shaft fixing hole 64a and the second support shaft fixing hole 64b provided on the bracket 60.

[0140] In addition, a first washer WS1 is provided on one axial side (lower side in the figure) of the third ball bearing BB3 and on the other axial side (upper side in the figure) of the fourth ball bearing BB4. Thus, the planetary gear 50 equipped with the third ball bearing BB3 and the fourth ball bearing BB4 can smoothly rotate relative to the bracket 60 and the support shaft 52 without shaking.

[0141] [bracket]

[0142] like Figure 3 and Figure 7 As shown, the bracket 60 is formed into a substantially cylindrical shape by cutting aluminum material, etc. The bracket 60 includes a cylindrical body 61, and a total of three gear support parts 62 are provided on the cylindrical body 61. Each gear support part 62 has a function of supporting the planetary gear 50 rotatably.

[0143] Here, the carrier 60 rotatably supports a total of three planetary gears 50 , and corresponds to a planetary carrier in the present invention.

[0144] The gear support portion 62 is arranged at equal intervals (120 degree intervals) in the circumferential direction of the cylindrical body portion 61, and includes a connecting hole 62a that connects the radial inner side and the radial outer side of the cylindrical body portion 61. The connecting hole 62a is formed in a substantially square shape when the bracket 60 is viewed from the side. Moreover, the planetary gear 50 is rotatably accommodated in the connecting hole 62a with a small gap therebetween.

[0145] In addition, the carrier 60 is one of the parts that require particularly high processing accuracy among the parts that form the planetary gear reduction mechanism 10 in order to allow the planetary gear 50 to rotate smoothly without rattling.

[0146] In addition, a first base 63a and a second base 63b are provided on both sides of the axial communication hole 62a of the bracket 60 to support both axial sides of the planetary gear 50. Specifically, the first base 63a is arranged on one axial side (lower side in the figure) of the bracket 60, and the second base 63b is arranged on the other axial side (upper side in the figure) of the bracket 60. Moreover, the first washers WS1 respectively provided on both axial sides of the planetary gear 50 are in contact with the first base 63a and the second base 63b respectively.

[0147] An input side cylindrical portion 65 having a smaller diameter than the cylindrical main body portion 61 is provided on one axial side of the bracket 60. An insertion hole 65a for inserting the input shaft 31 (pinion gear 30) is provided on the radially inner side of the input side cylindrical portion 65, and a fifth ball bearing BB5 for rotatably supporting the input shaft 31 is installed in the insertion hole 65a. Specifically, the outer ring (outer race) of the fifth ball bearing BB5 is installed in the insertion hole 65a.

[0148] In addition, the inner ring (inner race) of the fifth ball bearing BB5 is fixed to the substantially central portion (near the pinion gear 30) in the axial direction of the input shaft 31 by press-fitting. Here, one axial side of the input side cylindrical portion 65 is covered by a cover member 67 formed in a substantially disc shape. The cover member 67 has a function of preventing the fifth ball bearing BB5 from falling off from the input side cylindrical portion 65. In other words, the cover member 67 has a function of preventing the input shaft 31 to which the fifth ball bearing BB5 is fixed from falling off relative to the bracket 60.

[0149] Furthermore, the cover member 67 is provided with a total of three screw insertion holes 67a (see Fig.11 ), a total of three threaded holes 65b are provided on one axial side of the input side cylindrical portion 65. In addition, fixing screws (not shown) for fixing the cover member 67 to the input side cylindrical portion 65 are screwed into the total of three threaded holes 65b.

[0150] In addition, the inner ring of the second ball bearing BB2 is installed on the radially outer side of the input side cylindrical portion 65, and the inner ring of the second ball bearing BB2 abuts against the first step portion ST1 between the tubular body portion 61 and the input side cylindrical portion 65 from one axial side (see Figure 7 ).

[0151] Furthermore, a first support shaft fixing hole 64a is provided in a portion of the input side cylindrical portion 65 where the first base 63a is provided so as to extend in the axial direction of the bracket 60. Three first support shaft fixing holes 64a are provided corresponding to the first base 63a, and are arranged at equal intervals (120 degree intervals) in the circumferential direction of the cylindrical body portion 61. Moreover, the first support shaft fixing hole 64a penetrates both the first base 63a and the input side cylindrical portion 65, and one axial side (lower side in the figure) of the support shaft 52 that rotatably supports the planetary gear 50 is installed in the first support shaft fixing hole 64a.

[0152] In addition, an output side cylindrical portion 66 having the same diameter as the input side cylindrical portion 65 is provided on the other axial side of the bracket 60. A through hole 66a is provided on the radially inner side of the output side cylindrical portion 66, and a sixth ball bearing BB6 for rotatably supporting the other axial side of the input shaft 31 is installed in the through hole 66a, and a play adjustment member 68 for adjusting the play of the input shaft 31 relative to the bracket 60 in the axial direction is provided.

[0153] Specifically, the outer ring (outer race) of the sixth ball bearing BB6 is installed in the through hole 66a. In addition, the inner ring (inner race) of the sixth ball bearing BB6 is installed in the bearing installation portion 31a of the input shaft 31. In addition, the bearing installation portion 31a is cylindrical in shape with a diameter smaller than that of the main body of the input shaft 31, and a support step 31b is provided between the bearing installation portion 31a and the pinion 30 (see FIG. Figure 4 ). In addition, the inner ring of the sixth ball bearing BB6 is separated by the second washer WS2 (refer to Fig.11 ) and abuts against the support step 31b from the other axial side.

[0154] Furthermore, the second washer WS2 has a function of eliminating play between the sixth ball bearing BB6 and the input shaft 31 and allowing the input shaft 31 to rotate smoothly.

[0155] Here, the sixth ball bearing BB6 adopts an angular ball bearing. Thus, the sixth ball bearing BB6 presses the input shaft 31 to one axial side (lower side in the figure) while receiving the axial force from the sloshing adjustment member 68. Thus, the sloshing of the input shaft 31 between the fifth ball bearing BB5 and the sixth ball bearing BB6 can be suppressed, and the quietness of the planetary gear reduction mechanism 10 during operation is improved.

[0156] In addition, the shake adjustment member 68 is screwed to the through hole 66a, and by rotating the shake adjustment member 68 in the clockwise direction, the shake adjustment member 68 moves to one axial side (lower side in the figure). Moreover, the shake adjustment member 68 presses the outer ring of the sixth ball bearing BB6 toward one axial side. On the other hand, by rotating the shake adjustment member 68 in the counterclockwise direction, the shake adjustment member 68 moves to the other axial side (upper side in the figure).

[0157] In addition, the inner ring of the first ball bearing BB1 is installed on the radially outer side of the output side cylindrical portion 66, and the inner ring of the first ball bearing BB1 abuts against the second step portion ST2 (see FIG. 1 ) between the cylindrical body portion 61 and the output side cylindrical portion 66 from the other axial side. Figure 7 Specifically, a third washer WS3 is provided between the inner ring of the first ball bearing BB1 and the second step portion ST2 (see Fig.10 ), the inner ring of the first ball bearing BB1 abuts against the second step portion ST2 via the third washer WS3.

[0158] Furthermore, a second support shaft fixing hole 64b is provided at a portion of the output side cylindrical portion 66 where the second base 63b is provided so as to extend in the axial direction of the bracket 60. Three second support shaft fixing holes 64b are provided corresponding to the second base 63b, and are arranged at equal intervals (120 degree intervals) in the circumferential direction of the cylindrical body portion 61. Moreover, the second support shaft fixing hole 64b penetrates both the second base 63b and the output side cylindrical portion 66, and the other axial side (upper side in the figure) of the support shaft 52 that rotatably supports the planetary gear 50 is installed in the second support shaft fixing hole 64b.

[0159] Here, the support shaft 52 is inserted into the first support shaft fixing hole 64a to a degree that does not cause shaking, and is fixed in the second support shaft fixing hole 64b by being pressed. Fig. 9 ) when the support shaft 52 is inserted into the first support shaft fixing hole 64a and the second support shaft fixing hole 64b, thereby improving the assembly performance.

[0160] Furthermore, the first support shaft fixing hole 64 a and the second support shaft fixing hole 64 b for fixing both axial sides of the support shaft 52 respectively correspond to the support shaft fixing holes in the present invention.

[0161] Thus, the three second support shaft fixing holes 64b and the three first support shaft fixing holes 64a are respectively arranged coaxially in the axial direction of the bracket 60. Here, the bracket 60 is formed with high precision by cutting aluminum material, that is, formed in a manner without dimensional error. Figure 7 As shown, the rotation center C1 of the bracket 60 and the central axes (rotation center of the planetary gear 50) C2 of the first support shaft fixing hole 64a and the second support shaft fixing hole 64b arranged around the rotation center C1 are arranged at predetermined positions of the bracket 60 with good precision.

[0162] In addition, a plurality of internal thread portions 66b are provided on the other axial side (upper side in the figure) of the output side cylindrical portion 66. These internal thread portions 66b extend in the axial direction of the bracket 60. Furthermore, in the internal thread portions 66b, screws are screwed in to fix the coupling 70 (see Figures 1 to 3 ) fixing screws (not shown). In addition, also for the purpose of ensuring sufficient fixing strength, when the coupling 70 is fixed to the bracket 60, it is ideal to use at least three fixing screws.

[0163] [Coupling]

[0164] like Figures 1 to 3 As shown, the planetary gear reduction mechanism 10 includes a coupling (coupling) 70 connected to a driving mechanism (not shown) of a robot as a driven object in a manner capable of transmitting power. In addition, in the coupling 70, similarly to the bracket 60, it is formed with high precision by cutting aluminum materials, that is, it is formed in a manner without dimensional error.

[0165] The coupling 70 includes a fixed body portion 71 formed in a substantially disc shape, and an output shaft 72 integrally provided on the fixed body portion 71. The fixed body portion 71 is fixed to the output side cylindrical portion 66 of the bracket 60. The output shaft 72 extends from the other axial side (upper side in the figure) of the fixed body portion 71 toward the driving mechanism (not shown) of the robot and is substantially cylindrical.

[0166] The coupling 70 is a member fixed to the bracket 60 and drives a driving mechanism (not shown) of the robot, and corresponds to an output-side rotating body in the present invention.

[0167] like Figure 1 and Figure 3 As shown in FIG. 1 , a total of three fixing holes 71a are provided in the fixed body portion 71. These fixing holes 71a are arranged at equal intervals (120 degree intervals) in the circumferential direction of the fixed body portion 71 with the output shaft 72 as the center. In addition, the total of three fixing holes 71a and the total of three second support shaft fixing holes 64b provided on the output side cylindrical portion 66 of the bracket 60 (see FIG. 1 ) are arranged at equal intervals (120 degree intervals) in the circumferential direction of the fixed body portion 71. Figure 7 ) are set accordingly.

[0168] In the three fixing holes 71a in total, fixing pins 73 made of steel are fixed by press-fitting. These fixing pins 73 are inserted into the fixing holes 71a from the other axial side (upper side in the figure) of the coupling 70, and the axial one side (lower side in the figure) of the fixing pins 73 is fixed by press-fitting in the second support shaft fixing holes 64b of the bracket 60. That is, the fixing pins 73 fixed to the fixing body 71 are fixed to the second support shaft fixing holes 64b, respectively, and the coupling 70 is fixed to the bracket 60 by the fixing pins 73.

[0169] In this way, the fixing pin 73 is pressed into both the fixing hole 71a and the second support shaft fixing hole 64b, and the fixing hole 71a is equivalent to the fixing hole of the fixing member in the present invention. That is, the fixing pin 73 has the function of fixing the coupling 70 and the bracket 60, which are respectively formed (manufactured) with good accuracy, to each other. In addition, the fixing pin 73 is equivalent to the fixing member in the present invention.

[0170] Furthermore, by press-fitting and fixing the fixing pin 73 into both the fixing hole 71 a and the second support shaft fixing hole 64 b , the coupling 70 can be accurately positioned relative to the bracket 60 , and the two can be firmly fixed to each other.

[0171] Furthermore, a tapered portion 73a having a tapered tip is provided on one axial side of the fixing pin 73 so that the fixing pin 73 can be easily inserted into each of the fixing hole 71a and the second support shaft fixing hole 64b (improvement of assembly performance).

[0172] In addition, the fixing body portion 71 is provided with a plurality of screw insertion holes 71b for inserting fixing screws (not shown) for fixing the coupling 70 to the bracket 60. The screw insertion holes 71b are connected to a plurality of internal threaded portions 66b (see FIG. 1 ) provided on the output side cylindrical portion 66. Figure 7 ) are set accordingly.

[0173] [Assembly process]

[0174] Next, use Figures 8 to 12 The assembly process of the planetary gear reduction mechanism 10 formed as described above will be described in detail.

[0175] Figure 8 A three-dimensional diagram showing the assembly process of the bracket assembly is shown. Fig. 9 A perspective view showing the assembly process of the internal gear relative to the carrier assembly is shown. Fig.10 A perspective view showing the assembly process of the housing body and the ring member is shown. Fig.11 A perspective view showing the assembly process of the pinion gear and the shake adjustment member is shown. Fig.12 A perspective view showing the assembly process of the coupling relative to the bracket is shown.

[0176] [Assembly of bracket assembly]

[0177] like Figure 8 As shown, the bracket assembly CA is first assembled. Specifically, the bracket 60, a total of three planetary gears 50, and a total of three support shafts 52 manufactured through another manufacturing process are prepared. Figure 8 In the figure, for the sake of easy observation, one planetary gear 50 and one support shaft 52 are shown respectively.

[0178] Then, if Figure 8 As shown by the arrow M1, the planetary gear 50 faces the connecting hole 62a from the radial outer side of the bracket 60. At this time, the third ball bearing BB3 and the fourth ball bearing BB4 (see FIG. 1 ) are pre-installed on the radial inner side of the planetary gear 50. Figure 3 ). In addition, a first washer WS1 is installed on each of the third ball bearing BB3 and the fourth ball bearing BB4 (see Figure 3 ).

[0179] Then, the planetary gear 50 is inserted into the communication hole 62a, and Figure 8 As shown by arrow M2, the support shaft 52 faces the other axial side of the bracket 60. At this time, the input side cylindrical portion 65 of the bracket 60 is arranged on one axial side (lower side in the figure), and the output side cylindrical portion 66 of the bracket 60 is arranged on the other axial side (upper side in the figure).

[0180] Then, the support shaft 52 is inserted into the second support shaft fixing hole 64b and the first support shaft fixing hole 64a in sequence. In addition, the support shaft 52 is inserted into the first support shaft fixing hole 64a, and the support shaft 52 is pressed into the second support shaft fixing hole 64b. Thus, the insertion load of the support shaft 52 does not need to be too large, so that the bracket assembly CA can be easily assembled.

[0181] Then, the planetary gear 50 is mounted to the communication hole 62a twice as described above, thereby completing the bracket assembly CA (see FIG. Fig. 9 ) assembly work.

[0182] [Assembly of the internal gear to the carrier assembly]

[0183] Then, if Fig. 9 As shown in FIG. 1 , the ring gear 40 manufactured through another manufacturing process is prepared, and the operation of assembling the ring gear 40 to the already assembled carrier assembly CA is performed.

[0184] Specifically, as shown by arrow M3 in the figure, the ring gear 40 faces the other axial side of the carrier assembly CA, that is, the output side cylindrical portion 66 side (upper side in the figure). At this time, the fourth flange portion 42 side of the ring gear 40 in the axial direction faces the carrier assembly CA.

[0185] Then, the carrier assembly CA is arranged so as to overlap the ring gear 40 on the radially outer side. At this time, the planetary gear 50 of the carrier assembly CA can smoothly rotate relative to the carrier 60, so that the inner teeth 43a of the ring gear 40 and the meshing recess 51a of the planetary gear 50 mesh smoothly with each other.

[0186] Thereby, the assembly work of the ring gear 40 to the carrier assembly CA is completed.

[0187] [Assembly of the housing body and the ring member]

[0188] Then, if Fig.10 As shown, the housing body 21, the ring member 22 and the third washer WS3 manufactured through another manufacturing process are prepared. In addition, the first ball bearing BB1 is pre-installed in the housing body 21, and the second ball bearing BB2 is pre-installed in the ring member 22.

[0189] Then, as shown by arrow M4 in the figure, the third washer WS3 is installed on the output side cylindrical portion 66 of the bracket 60. Then, as shown by arrow M5 in the figure, the housing body 21 is installed in a manner overlapping the radial outer side of the ring gear 40. At this time, the first flange portion 21b side of the housing body 21 in the axial direction is directed toward the ring gear 40.

[0190] Then, as shown by arrow M6 in the figure, the ring member 22 (with the second ball bearing BB2) is installed on the input side cylindrical portion 65 of the bracket 60. At this time, the side of the ring member 22 provided with the positioning protrusion P is directed toward the internal gear 40. Then, while the second ball bearing BB2 is installed on the input side cylindrical portion 65, the positioning protrusion P of the ring member 22 is engaged with the engagement recess (not shown) of the internal gear 40.

[0191] Then, the fixing bolts (not shown) are inserted into the insertion holes 21c of the first flange portion 21b and the insertion holes 42a of the fourth flange portion 42, and the fixing bolts are screwed into the internal threaded holes 22c of the third flange portion 22b. Thus, the reducer SD is accommodated inside the housing 20, and the assembly of the housing body 21 and the ring member 22 is completed.

[0192] [Assembly of pinion gear and play adjustment member]

[0193] Then, if Fig.11 As shown, an input shaft 31 having a pinion 30 manufactured through a separate manufacturing process and a cover member 67 are prepared. In addition, a fifth ball bearing BB5 is fixed in advance to the input shaft 31. In addition, a second washer WS2, a sixth ball bearing BB6 and a play adjusting member 68 are also prepared.

[0194] Then, as shown by arrow M7 in the figure, the pinion gear 30 is directed toward the input side cylindrical portion 65 of the carrier 60 (see Figure 3 Then, the pinion gear 30 is inserted into a total of three planetary gears 50 (see Figure 6 ). At this time, the planetary gear 50 can smoothly rotate relative to the carrier 60. Therefore, while each planetary gear 50 rotates, the helical teeth 32 of the pinion 30 and the meshing recessed portion 51a (see Figure 6 ) mesh smoothly with each other.

[0195] Then, the fifth ball bearing BB5 is installed in the insertion hole 65a of the input side cylindrical portion 65 (see Figure 3 ). In addition, Fig.11 As shown by the arrow M8, the cover member 67 is fixed to the input side cylindrical portion 65 (refer to Figure 3 At this time, a total of three fixing screws (not shown) are inserted into the screw insertion holes 67a of the cover member 67 and screwed into the threaded holes 65b of the input-side cylindrical portion 65 (see Figure 3 ). This prevents the input shaft 31 (pinion gear 30) from coming off the carrier 60.

[0196] Next, as shown by arrow M9 in the figure, the second washer WS2 is placed in the through hole 66a of the output side cylindrical portion 66 and placed on the support step 31b of the input shaft 31. Then, the sixth ball bearing BB6 is placed in the through hole 66a of the output side cylindrical portion 66 and mounted on the bearing mounting portion 31a of the input shaft 31. Then, the play adjustment member 68 is screwed into the through hole 66a.

[0197] Then, as shown by arrow M10 in the figure, the play adjustment member 68 is rotated in the clockwise direction, and the outer ring of the sixth ball bearing BB6 is pressed toward one side in the axial direction by the play adjustment member 68. Thus, the play of the input shaft 31 in the axial direction is suppressed, and the assembly operation of the pinion gear 30 and the play adjustment member 68 is completed.

[0198] [Assembly of the coupling to the bracket]

[0199] Then, if Fig.12 As shown in FIG. 1 , a coupling 70 manufactured through a separate manufacturing process and a total of three fixing pins 73 are prepared.

[0200] Then, as shown by arrow M11 in the figure, the fixed body 71 of the coupling 70 is made to face the output side cylindrical portion 66 of the bracket 60. At this time, the total of three fixing holes 71a provided in the fixed body 71 and the total of three second support shaft fixing holes 64b provided in the output side cylindrical portion 66 are made to face each other in the axial direction (arranged on the same axis).

[0201] Then, as shown by arrows M12 in the figure, three fixing pins 73 are sequentially pressed into the fixing hole 71a and the second support shaft fixing hole 64b, with the side of the fixing pin 73 provided with the tapered portion 73a facing the fixing body 71.

[0202] Thus, the coupling 70 is accurately positioned relative to the bracket 60 and is firmly fixed. Then, the coupling 70 is fixed to the bracket 60 using a plurality of fixing screws (not shown). At this time, any of the screw insertion holes 71b of the fixing body 71 and any of the internal threaded portions 66b of the output side cylindrical portion 66 are used. In addition, from the viewpoint of fixing strength, it is also desirable to use three fixing screws to fix the coupling 70 to the bracket 60.

[0203] Thus, the coupling 70 is not separated from the carrier 60 due to vibration or the like when the planetary gear reduction mechanism 10 is driven, and finally, the assembly work of the planetary gear reduction mechanism 10 is completed.

[0204] As described in detail above, according to the planetary gear reduction mechanism 10 of embodiment 1, a first support shaft fixing hole 64a and a second support shaft fixing hole 64b for fixing the support shaft 52 are provided on the bracket 60, and the support shaft 52 supports the planetary gear 50 to rotate freely, and the coupling 70 is fixed to the bracket 60 by a fixing pin 73 fixed to the second support shaft fixing hole 64b.

[0205] Thus, the coupling 70 can be fixed with high accuracy to the bracket 60 formed with high processing accuracy. Therefore, the planetary gear reduction mechanism 10 can be realized which can drive the driving mechanism of a robot or the like as a driven object with high accuracy.

[0206] According to the planetary gear reduction mechanism 10 of the first embodiment, the three planetary gears 50 are provided at equal intervals (120 degree intervals) in the circumferential direction of the pinion gear 30 , and the coupling 70 is fixed to the carrier 60 by the three fixing pins 73 .

[0207] Thus, the pinion gear 30 can be held in a balanced manner by the three planetary gears 50. Thus, the operating noise of the planetary gear reduction mechanism 10 can be reduced, and power can be efficiently transmitted from the pinion gear 30 to the three planetary gears 50. In addition, the coupling 70 can be fixed to the bracket 60 in a balanced manner at three points by the three fixing pins 73.

[0208] Furthermore, according to the planetary gear reduction mechanism 10 of the first embodiment, the fixing pin 73 is press-fitted into both the fixing hole 71 a provided in the coupling 70 and the second support shaft fixing hole 64 b provided in the bracket 60 .

[0209] Thus, the coupling 70 can be firmly fixed to the bracket 60 without causing rattling.

[0210] Furthermore, according to the planetary gear reduction mechanism 10 of the first embodiment, the pinion gear 30 has only one helical tooth 32 that is helically connected in the axial direction of the input shaft 31 .

[0211] This can improve the transmission efficiency of the gears, and can achieve a large reduction ratio while being small. Therefore, the electric motor as a drive source can be made smaller and more energy-efficient.

[0212] Furthermore, according to the planetary gear reduction mechanism 10 of embodiment 1, in addition to using the second support shaft fixing hole 64b provided in the bracket 60 for supporting the support shaft 52, it is also used for supporting the fixing pin 73. That is, there is no need to newly provide a support structure for supporting the fixing pin 73, which can save the manufacturing energy of the planetary gear reduction mechanism 10. Therefore, the Sustainable Development Goals (SDGs) formulated by the United Nations, especially Goal 7 (ensuring access to affordable, reliable, sustainable and modern energy for all) and Goal 13 (taking urgent action to address climate change and its impacts) can be achieved.

[0213] [Implementation Method 2]

[0214] Next, Embodiment 2 of the present invention will be described in detail with reference to the drawings. Note that the same reference numerals are given to portions having the same functions as those of Embodiment 1, and detailed descriptions thereof will be omitted.

[0215] Fig.13 The planetary gear reduction mechanism of the second embodiment is shown in FIG. Figure 3 The corresponding cross-section diagram.

[0216] like Fig.13 As shown, the planetary gear reduction mechanism 100 of the second embodiment is different from the planetary gear reduction mechanism 10 of the first embodiment (see Figure 3 ) only the shape of the coupling (output side rotating body) 110 is different.

[0217] The coupling 110 includes: a fixed body portion 71 formed in a substantially disc shape; and an output shaft 111 integrally provided on the fixed body portion 71 and formed in a substantially cylindrical shape. Figure 3 As shown in the first embodiment, a substantially cylindrical output shaft 72 is provided on the fixed body portion 71, but as shown in FIG. Fig.13 As shown, in the second embodiment, a substantially cylindrical output shaft 111 is provided on the fixed body portion 71 .

[0218] In the second embodiment formed as described above, the same effects as those of the first embodiment can be achieved.

[0219] As in the first embodiment (planetary gear reduction mechanism 10) and the second embodiment (planetary gear reduction mechanism 100), the shapes of the output shaft 72 and the output shaft 111 provided in the coupling 70 and the coupling 110 can be arbitrarily set corresponding to the shape of the robot's drive mechanism or other drive mechanism, that is, the shape of the driven object.

[0220] The present invention is not limited to the above-mentioned embodiments, and various changes can be made without departing from the scope of the present invention. For example, in the above-mentioned embodiments, a total of six bearings are all set as the first ball bearing BB1 to the sixth ball bearing BB6, but the present invention is not limited to this, and some bearings can also be replaced with bushings or bearings also called sliding bearings.

[0221] In addition, in each of the above-mentioned embodiments, a total of three planetary gears 50 are provided, but the present invention is not limited thereto, and four or more planetary gears 50 may be provided. In addition, if there are two (an even number) of planetary gears 50, they are arranged 180 degrees opposite to each other, and it is difficult to maintain the pinion 30 in a balanced manner. Therefore, it leads to an increase in working noise or a decrease in power transmission efficiency. On the other hand, if there are five or more planetary gears 50, the assembly performance is reduced or it leads to enlargement. Therefore, when used for purposes such as the above-mentioned embodiments, the number of planetary gears 50 is ideally three (an odd number).

[0222] Furthermore, the assembly process of the planetary gear reduction mechanism 10 is only one example of several assembly processes, and other assembly processes can also be used for assembly. Fig.10 The process is performed at a stage prior to the "assembly of the housing body 21 and the ring member 22" shown in FIG. Fig.11 “Assembly of the pinion gear 30 and the play adjusting member 68 ” shown in FIG.

[0223] In addition, as long as the present invention can be achieved, the material, shape, size, number, installation location, etc. of each component in the above-mentioned embodiments are arbitrary and are not limited to the above-mentioned embodiments.

Claims

1. A planetary gear reduction mechanism having a plurality of gears, The planetary gear reduction mechanism comprises: An input-side rotating body connected to a driving source in a manner capable of transmitting power; A sun gear, disposed on the input-side rotating body; An internal gear, disposed radially outward of the sun gear; A planetary gear, disposed between the sun gear and the internal gear; A planet carrier, supporting the planetary gears to rotate freely; as well as The output side rotating body is fixed to the planetary carrier and drives the driven object. The planetary carrier is provided with a support shaft fixing hole for fixing a support shaft, and the support shaft rotatably supports the planetary gear. The output-side rotating body is fixed to the planetary carrier via a fixing member fixed to the support shaft fixing hole.

2. The planetary gear reduction mechanism according to claim 1, wherein: At least three of the planetary gears are arranged at equal intervals in the circumferential direction of the sun gear. The output-side rotating body is fixed to the planetary carrier via at least three of the fixing members.

3. The planetary gear reduction mechanism according to claim 1, wherein: The fixing member The fixing member is press-fitted into both the fixing member fixing hole provided in the output-side rotating body and the supporting shaft fixing hole provided in the planetary carrier.

4. The planetary gear reduction mechanism according to any one of claims 1 to 3, wherein: The sun gear has only one tooth which is spirally connected in the axial direction of the input-side rotating body.

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