Speed ​​reducer

Abstract

The object of the present invention is to provide a reduction gear device capable of ensuring lubrication. The reduction gear device (100) comprises a housing (30), a reduction mechanism (10) contained in the housing (30), and a lubricant (58) contained in the housing (30). The reduction gear device further comprises a lubricant tank (50) which is connected to a space in the housing (30), and the lubricant (58) can flow between the lubricant tank (50) and the space in the housing (30). When changing from a first posture to a second posture, the lubricant (58) in the housing (30) retreats to the lubricant tank (50), and when changing from the second posture to the first posture, the lubricant (58) in the lubricant tank (50) is supplied to the housing (30).

Description

[0001] This application claims priority based on Japanese Patent Application No. 2020-058926 filed on March 27, 2020. The entire contents of the Japanese Patent Application are incorporated herein by reference. Technical Field

[0002] The invention relates to a reduction gear. Background Art

[0003] Patent Document 1 describes a speed reducer that reduces the speed of rotation input to an input shaft and outputs the rotation to an output shaft. The speed reducer includes a plurality of gears surrounded by a housing. The speed reducer is configured to drive a hydraulic pump to inject oil into a lubricated portion.

[0004] Patent Document 1: Japanese Utility Model Publication No. 51-52175

[0005] In a structure in which a lubrication portion is lubricated by driving a hydraulic pump as in the speed reducer described in Patent Document 1, lubrication may not be ensured when a failure occurs in the hydraulic pump. Summary of the invention

[0006] The present invention has been made in view of such a problem, and one object of the present invention is to provide a reduction gear device capable of ensuring lubrication.

[0007] In order to solve the above-mentioned problems, a reduction gear according to one embodiment of the present invention comprises a housing, a reduction mechanism contained in the housing, and a lubricant contained in the housing, and the reduction gear comprises a lubricant tank, the lubricant tank is connected to the space in the housing, and the lubricant can flow between the lubricant tank and the space in the housing. When changing from a first posture to a second posture, the lubricant in the housing retreats into the lubricant tank, and when changing from the second posture to the first posture, the lubricant in the lubricant tank is supplied to the housing.

[0008] In addition, any combination of the above-mentioned constituent elements or any form in which constituent elements or expressions of the present invention are mutually replaced in methods, systems, etc. may also be practiced as additional embodiments of the present invention.

[0009] According to the present invention, a reduction gear device capable of ensuring lubrication is provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a side view schematically showing a driven device to which the reduction gear device according to the embodiment is mounted.

[0011] Figure 2 It is a side view schematically showing the reduction gear transmission according to the embodiment.

[0012] Figure 3 Yes means Figure 2A top view of the lubricant tank of the reduction gear unit.

[0013] Figure 4 Yes means Figure 2 Side view of the lubricant tank of the reduction gear.

[0014] Figure 5 Yes means Figure 2 Front view of the lubricant tank of the reduction gear unit.

[0015] Figure 6 Yes means Figure 2 A side sectional view of the periphery of a connecting tank of a reduction gear device.

[0016] Figure 7 It is along Figure 6 Sectional view taken along line AA.

[0017] Figure 8 It indicates schematically Figure 2 A side view of the state of the lubricant of the reduction gear.

[0018] Fig. 9 It indicates schematically Figure 2 A side view of the state of the lubricant of the reduction gear.

[0019] In the figure: 10-reduction mechanism, 30-housing, 30a-space inside the housing, 40-connecting flange, 41-introduction cylinder, 41h-supply hole, 50-lubricant tank, 50a-space inside the tank, 51-tank body, 58-lubricant, L58-liquid level, 60-connecting tank, 63g-guide surface, 70-motor, 80-driven device, 100-reduction device. DETAILED DESCRIPTION

[0020] The inventors of the present invention have studied a reduction gear device that reduces input rotation and then drives a driven device, and have obtained the following insights. Depending on the application, the reduction gear device may sometimes operate in an environment where the posture changes. For example, the reduction gear device installed on the electric cylinder of the crane arm drives the driven part of the electric cylinder to swing the arm up and down. When the arm swings up and down, the posture of the reduction gear device (the angle between the axial direction and the horizontal direction) changes integrally with the angle of the electric cylinder.

[0021] Since the appropriate amount of lubricant for the reduction gear varies depending on the posture, if the posture changes, in the method of maintaining a certain amount of lubricant, the amount of lubricant may be excessive or insufficient depending on the posture. Therefore, it is possible to consider placing a forced circulation device of the forced circulation lubrication method outside the reduction gear and controlling the amount of lubricant through the forced circulation device. However, in this method, when a failure occurs in the forced circulation device or when the lubricant leaks from the external piping, etc., there is a possibility that the lubricant is insufficient.

[0022] Therefore, the inventors have come up with a mechanism that can adjust the lubricant amount of the reduction gear according to the posture of the reduction gear even without using a forced circulation device. According to the adjustment mechanism, even if the posture of the reduction gear changes, an appropriate lubricant amount can be achieved in each posture, and the reduction gear can be operated stably. The following is a description of the implementation method.

[0023] Hereinafter, the preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the embodiments and modified examples, the same or equivalent components and parts are marked with the same symbols, and repeated descriptions are appropriately omitted. In addition, in order to facilitate understanding, the size of the components is appropriately enlarged or reduced in each of the drawings. In addition, in each of the drawings, a part of the components that are not important in the description of the embodiments is omitted.

[0024] Furthermore, terms including numbers such as 1 and 2 are used to describe various constituent elements, but such terms are only used to distinguish one constituent element from other constituent elements, and such terms are not used to limit the constituent elements.

[0025] [Implementation Method]

[0026] refer to Figure 1 Next, a driven device 80 to which the reduction gear device 100 according to the embodiment of the present invention is mounted will be described. Figure 1 1 is a side view schematically showing a driven device 80 to which the reduction gear 100 is mounted. Figure 1 The reduction gear 100 is mounted on the driven device 80, and its posture changes between a first posture and a second posture described later based on the movement of the driven device 80. The reduction gear 100 reduces the rotation of the motor 70 and then drives the driven device 80 to rotate.

[0027] exist Figure 1 In the example of , the driven device 80 is an electric cylinder having a cylinder body 83 and an output rod 84, and the output rod 84 moves forward and backward relative to the cylinder body 83 according to the rotation input to the driven member 85 (for example, the input gear). The reduction gear 100 transmits the rotation output to the output shaft 14 to the driven member 85 via the output gear 15. The driven device 80 is mounted on a device having an arm (not shown) such as a crane, and the arm is raised by extending the output rod 84, and the arm is lowered by retracting the output rod 84. In the following description, vertical relative to the horizontal plane is simply referred to as vertical.

[0028] As an example, when the arm's chamfer angle is maximum (e.g., vertical), as shown by the solid line, the driven device 80 and the reduction gear 100 are in a large tilted posture with the axial direction tilted 90° from the horizontal direction. And, when the arm's chamfer angle is 0° (horizontal), as shown by the dotted line, the driven device 80 and the reduction gear 100 are in a low tilted posture with the axial direction closer to the horizontal direction than in the large tilted posture. The reduction gear 100 is equipped with a lubricant tank 50, which supplies lubricant or allows the lubricant to retreat to the lubricant tank 50 according to the posture in order to ensure appropriate lubrication in each posture.

[0029] Below, reference Figure 2 The overall structure of the reduction gear transmission 100 will be described. Figure 2 FIG. 1 is a side view showing the reduction gear 100 , and a portion thereof is shown in cross section. Figure 2 , the reduction gear 100 in the second posture described later is shown in a state where the center axis La described later becomes horizontal. The reduction gear 100 includes a reduction mechanism 10, a housing 30, a lubricant tank 50, and a lubricant 58. The reduction gear 100 includes a connecting flange 40 for connecting the reduction gear 100 to the motor 70. The lubricant tank 50 includes a tank body 51 disposed on the motor 70 side of the connecting flange 40 and a connecting tank 60 disposed on the reduction gear 100 side of the connecting flange 40. The tank body 51 and the connecting tank 60 are connected to each other through a connecting hole provided in the connecting flange 40. The tank body 51 is disposed on the lower side of the motor 70 in the second posture, and the connecting tank 60 is disposed on the lower side of the reduction mechanism 10 in the second posture. The connecting flange 40 and the lubricant tank 50 will be described later.

[0030] The reduction gear 100 reduces the speed of the rotation input from the motor 70 and outputs it from the output shaft 14 to the external driven device 80. Hereinafter, the direction along the center axis La of the output shaft 14 will be referred to as the "axial direction", the circumferential direction of a circle with the center axis La as the center will be referred to as the "circumferential direction", and the radial direction of a circle with the center axis La as the center will be referred to as the "radial direction". Also, hereinafter, for the sake of convenience, one side in the axial direction (the side of the reduction gear 10 where the motor 70 is arranged) will be referred to as the input side, and the other side will be referred to as the opposite input side. Also, sometimes, the direction orthogonal to the axial direction in the horizontal plane when the center axis La is facing the horizontal direction will be referred to as the "width direction", and will be indicated by the arrow W. Also, in Figure 2 In the diagram, the direction of arrow Z is sometimes referred to as "upper side" or "up", and the direction opposite to the direction of arrow Z is sometimes referred to as "lower side" or "down". Also, the state of viewing along the direction of arrow X in the axial direction is referred to as front view. Also, the state of viewing along the direction of arrow Z is referred to as top view.

[0031] The speed reduction mechanism 10 reduces the speed of the rotation input from the motor 70 and outputs it to the output shaft 14. An output gear 15 is fixed to the end of the output shaft 14 on the opposite side of the input side, and is engaged with an input gear (not shown) of the driven device 80 to transmit the rotation. The output gear 15 is spline-connected to the output shaft 14, for example.

[0032] The housing 30 is a housing that accommodates the speed reduction mechanism 10 and the lubricant 58, and defines a housing inner space 30a. The lubricant 58 is accommodated in the housing 30 and lubricates the speed reduction mechanism 10, and also participates in cooling the speed reduction mechanism 10. The lubricant tank 50 is configured to communicate with the housing inner space 30a, so that the lubricant 58 can flow between it and the housing inner space 30a.

[0033] The reduction gear 100 is configured such that when the reduction gear 100 changes from the first posture to the second posture, the lubricant 58 in the housing 30 is withdrawn into the lubricant tank 50, and when the reduction gear 100 changes from the second posture to the first posture, the lubricant 58 in the lubricant tank 50 is supplied to the housing 30 via the connecting tank 60. In this specification, the inclination of the axial direction of the reduction gear 100 with respect to the horizontal direction is referred to as "axial inclination".

[0034] The first posture is a posture in which the axial direction is closer to the vertical direction (the axial inclination is close to 90°) than the second posture, and the second posture is a posture in which the axial inclination is closer to 0° (horizontal) than the first posture. Hereinafter, for the sake of convenience, the first posture is set as a posture in which the output shaft 14 of the reduction gear 100 is located at the bottom and the axial inclination is 90° (vertical), and the second posture is set as a posture in which the axial inclination of the reduction gear 100 is 0° (horizontal). The description of the inclination is not used to limit the range of change of the posture of the reduction gear 100.

[0035] Next, the reduction mechanism 10 will be described. The structure of the reduction mechanism 10 is not limited, but in this example, the reduction mechanism 10 has a first-stage reduction gear 16, a second-stage reduction gear 17, a third-stage reduction gear 18, and a fourth-stage reduction gear 19, all of which are simple planetary reduction gears. The first-stage reduction gear 16, the second-stage reduction gear 17, the third-stage reduction gear 18, and the fourth-stage reduction gear 19 are sequentially connected in stages, so that the input rotation is sequentially reduced and then output to the output shaft 14.

[0036] The first stage speed reducer 16 has a first input shaft 16j, a first sun gear 16s, a first planetary gear 16p, a first planetary pin 16b, a first carrier 16c, and a first internal gear 16d. The second stage speed reducer 17 has a second input shaft 17j, a second sun gear 17s, a second planetary gear 17p, a second planetary pin 17b, a second carrier 17c, and a second internal gear 17d. The third stage speed reducer 18 has a third input shaft 18j, a third sun gear 18s, a third planetary gear 18p, a third planetary pin 18b, a third carrier 18c, and a third internal gear 18d. The fourth stage speed reducer 19 has a fourth input shaft 19j, a fourth sun gear 19s, a fourth planetary gear 19p, a fourth planetary pin 19b, a fourth carrier 19c, and a fourth internal gear 19d.

[0037] The first to fourth stage reducers 16 to 19 are all constructed as follows: rotation is input from the 1st to 4th sun gears 16s to 19s that rotate integrally with the 1st to 4th input shafts 16j to 19j, and the 1st to 4th planetary gears 16p to 19p are made to revolve between the 1st to 4th sun gears 16s to 19s and the 1st to 4th internal gears 16d to 19d, and the revolution of the 1st to 4th planetary gears 16p to 19p is transmitted to the 1st to 4th wheel carriers 16c to 19c via the 1st to 4th planetary pins 16b to 19b, and output from the 1st to 4th wheel carriers 16c to 19c.

[0038] The first to fourth input shafts 16j to 19j are coaxially arranged with the center axis La. The first input shaft 16j is connected to the motor shaft 72, and the rotation of the motor 70 is input to the first input shaft 16j. The first input shaft 16j and the motor shaft 72 are respectively inserted into the sleeve body 64 from opposite directions, and are spline-connected to the sleeve body 64, for example. The second to fourth input shafts 17j to 19j are connected to the first to third wheel carriers 16c to 18c of the preceding stage, and the output rotations of the first to third stage speed reducers 16 to 18 of the preceding stage are input to the second to fourth input shafts 17j to 19j.

[0039] The first to fourth sun gears 16s to 19s are fixed to the outer circumferences of the anti-input side portions of the first to fourth input shafts 16j to 19j, and rotate integrally with the first to fourth input shafts 16j to 19j.

[0040] A plurality of first to fourth planetary gears 16p to 19p (three in this example) are arranged at equal intervals in the circumferential direction. The first to fourth planetary gears 16p to 19p are externally meshed with the first to fourth sun gears 16s to 19s and internally meshed with the first to fourth internal gears 16d to 19d.

[0041] The first to fourth internal gears 16d to 19d are fixed to the housing 30. More specifically, the first internal gear 16d, the second internal gear 17d, and the fourth internal gear 19d are formed integrally with the first outer housing 31, the second outer housing 32, and the fourth outer housing 34 described later, and the third internal gear 18d is fixed to the third outer housing 33 in a state of being fitted therein.

[0042] The first to fourth planetary pins 16b to 19b pass through the center holes of the first to fourth planetary gears 16p to 19p. The first to fourth planetary gears 16p to 19p are rotatably supported on the first to fourth planetary pins 16b to 19b via roller bearings. In particular, two rows of roller bearings are provided between the fourth planetary gear 19p and the fourth planetary pin 19b. The input opposite side of each of the first to fourth planetary pins 16b to 19b is fixed to the first to fourth wheel carriers 16c to 19c.

[0043] The 1st to 4th wheel carriers 16c to 19c are roughly disk-shaped components arranged on the opposite side of the input of the 1st to 4th planetary gears 16p to 19p, and rotate around the center axis La. The 2nd to 4th input shafts 17j to 19j are spline-connected to the center holes of the 1st to 3rd wheel carriers 16c to 18c, for example. The output shaft 14 is spline-connected to the center hole of the 4th wheel carrier, for example. The 1st to 4th planetary pins 16b to 19b are coupled to offset holes provided at positions radially offset from the center holes of the 1st to 4th wheel carriers 16c to 19c by press-fitting or the like.

[0044] The fourth stage speed reducer 19 has an input side carrier body 19e arranged on the input side of the fourth planetary gear 19p. The input side carrier body 19e is a hollow annular component that surrounds the fourth input shaft 19j with a gap between it and the fourth input shaft 19j. The input side of the fourth planetary pin 19b is coupled to an offset hole provided at a position radially offset from the center of the input side carrier body 19e by pressing or the like. The fourth carrier 19c and the input side carrier body 19e are connected together by three connecting components 19f extending in the axial direction. Each connecting component 19f is arranged in the circumferential gap between each fourth planetary gear 19p.

[0045] Next, the housing 30 will be described. The housing 30 as a whole has a substantially cylindrical shape extending in the axial direction. The housing 30 includes a connecting flange 40, an introduction cylinder 41, a first housing body 31, a second housing body 32, a third housing body 33, a fourth housing body 34, a fifth housing body 35, a sixth housing body 36, a seventh housing body 37, an eighth housing body 38, and a second cover 39, which are sequentially connected from the input side toward the opposite input side. The first to eighth housing bodies 31 to 38 may be cylindrical bodies connected to each other in an integral manner by welding or bolt fastening, or a part or the whole thereof may be formed in an integral manner.

[0046] The first internal gear 16d, the second internal gear 17d, and the fourth internal gear 19d are integrally formed on the inner circumference of the first outer shell 31, the second outer shell 32, and the fourth outer shell 34. The third internal gear 18d is fitted and fixed on the inner circumference of the third outer shell 33. The eighth outer shell 38 is provided with an input opposite side flange 38f protruding toward the radial outer side. The input opposite side flange 38f is fixed to the mounting portion 82 of the driven device 80 by bolts B38, thereby fixing the reduction gear 100 to the driven device 80.

[0047] A first main bearing 28 is provided between the sixth outer casing 36 and the output shaft 14. A second main bearing 29 is provided between the eighth outer casing 38 and the output shaft 14. Figure 2 In the example of FIG. 1 , the first main bearing 28 and the second main bearing 29 are, for example, two rows of cylindrical roller bearings disposed face to face. The output shaft 14 is supported by the housing 30 via the first main bearing 28 and the second main bearing 29 that are spaced apart in the axial direction.

[0048] The second cover portion 39 is connected to the input opposite side of the eighth housing 38. The second cover portion 39 has a thick plate shape that blocks the input opposite side of the eighth housing 38. The second cover portion 39 is connected to the end surface of the input opposite side of the eighth housing 38 by bolts B39. The second cover portion 39 has a hollow cylindrical cover cylindrical portion 39p that protrudes from the end surface of the input opposite side toward the input opposite side. The cover cylindrical portion 39p is provided with an output shaft hole 39h through which the output shaft 14 passes.

[0049] An input-opposite-side oil seal 39s is fixed to the inner circumferential surface of the cover cylindrical portion 39p. The input-opposite-side oil seal 39s includes two rows of seal bodies arranged adjacent to each other in the axial direction. The inner circumferential side of the input-opposite-side oil seal 39s contacts the outer circumferential surface of the output shaft 14. The input-opposite-side oil seal 39s suppresses leakage of the lubricant 58 from the housing inner space 30a to the outside.

[0050] The introduction tube portion 41 is connected to the input side of the first outer housing 31. The introduction tube portion 41 surrounds the first input shaft 16j, the motor shaft 72, and the sleeve body 64. The inner space 41a of the introduction tube portion 41 constitutes a part of the housing inner space 30a.

[0051] Also refer to Figure 6 . Figure 6 4 is a side sectional view showing the periphery of the connecting tank 60. The housing 30 has a supply hole 41h for the lubricant 58. In this embodiment, Figure 6As shown, the supply hole 41h is provided on the introduction cylinder 41 arranged at a position closer to the input side than the reduction mechanism 10. The supply hole 41h for the lubricant 58 is provided on the peripheral wall surface located below the central axis La in the second posture of the introduction cylinder 41. The supply hole 41h has a rectangular shape whose length direction extends axially when viewed from above. A connecting tank 60 that guides the lubricant 58 from the lubricant tank 50 to the space 30a inside the housing is connected to the outer peripheral side of the supply hole 41h. Through this structure, the supply hole 41h is connected to the tank space 50a in the lubricant tank 50. The connecting tank 60 and the lubricant tank 50 will be described later.

[0052] The connecting flange 40 is connected to the input side of the introduction cylinder 41, and the intermediate flange 41f is connected to the opposite side of the input. The connecting flange 40 has a thick plate shape that blocks the input side of the introduction cylinder 41. The connecting flange 40 and the intermediate flange 41f are connected to the introduction cylinder 41 by welding or the like. The connecting flange 40 and the intermediate flange 41f protrude radially outward from the outer periphery of the introduction cylinder 41 and are flange-shaped.

[0053] Also refer to Figure 7 . Figure 7 It is along Figure 6 When viewed from the axial direction, the connecting flange 40 has a circular upper portion and a rectangular lower portion (see also FIG. Figure 7 The connecting flange 40 is provided with a motor shaft hole 40h through which the motor shaft 72 passes.

[0054] A plurality of reinforcing plates 43 arranged at predetermined intervals in the circumferential direction are fixed to the introduction cylinder 41 and the connecting flange 40. The reinforcing plate 43 is a polygonal plate-like member having two sides sandwiching a right angle, and the two sides are fixed to the outer cylinder surface of the introduction cylinder 41 and the end surface of the connecting flange 40 on the opposite side of the input by welding.

[0055] like Figure 2 As shown, the motor flange 70f of the motor 70 is connected to the input side surface of the connecting flange 40 by bolts B40. An input side sealing unit 68 is provided on the opposite side of the input of the connecting flange 40. The input side sealing unit 68 includes a hollow cylindrical sealing holding portion 68h fixed to the connecting flange 40 by welding or the like and an input side oil seal 68s fixed to the inner peripheral surface of the sealing holding portion 68h. The inner peripheral side of the input side oil seal 68s contacts the outer peripheral surface of the sleeve body 64. The input side oil seal 68s suppresses the leakage of the lubricant 58 from the space 30a inside the housing to the outside.

[0056] The motor 70 includes a cylindrical motor case 70m that extends from a motor flange 70f toward the input side and surrounds an internal mechanism. The structure of the motor 70 is not limited, but in this embodiment, the motor 70 is an inverter motor.

[0057] Next, refer to Figure 2 to Figure 5 , the lubricant tank 50 will be described. Figure 3 is a top view of the lubricant tank 50, Figure 4 is a side view of the lubricant tank 50, Figure 5 5 is a front view of the lubricant tank 50. In these figures, the periphery of the tank body 51 in the lubricant tank 50 is mainly shown. As described above, the lubricant tank 50 is a tank through which the lubricant 58 can flow between the lubricant tank 50 and the housing inner space 30a. The lubricant tank 50 of this embodiment includes a tank body 51, a tank connecting plate 52, a side plate 53, a vent 54, a communication pipe 55, and a connecting tank 60.

[0058] The tank body 51 is a metal plate box surrounding the tank space 50a in a rectangular shape that is flattened vertically, and has an opening 51h on the opposite side of the input. The tank connecting plate 52 is a thick plate member for connecting the tank body 51 to the speed reduction mechanism 10. When viewed from the front, the tank connecting plate 52 has a horizontally long rectangular shape with an arc-shaped notch on the upper side. Figure 5 As shown in FIG. 1 , the tank connecting plate 52 is provided with a first communicating hole 52h and a plurality of bolt holes 52k, each of which penetrates in the axial direction. When viewed from the front, the first communicating hole 52h has a horizontally long rectangular shape. The tank connecting plate 52 is fixed to the tank body 51 by welding or the like in a manner closing the opening 51h. The first communicating hole 52h is connected to the tank internal space 50a of the lubricant tank 50 via the opening 51h.

[0059] The side plates 53 are a pair of plate-like members fixed to both side surfaces in the width direction of the tank body 51 by welding or the like. When viewed from the side, the side plates 53 have an outer shape that covers the side surfaces of the tank body 51, and have an inclined portion on the upper side thereof that inclines upward from the input side toward the opposite input side. The edge 53f of the opposite input side of the side plate 53 is fixed to the input side of the tank connecting plate 52 by welding or the like, thereby reinforcing the tank body 51.

[0060] Next, refer to Figure 2 to Figure 5 , the vent 54 will be described. The vent 54 is connected to the through hole 41j provided in the introduction cylinder 41 via the communication pipe 55. The vent 54 of this embodiment is provided on the side of the lubricant tank 50, and has a through hole that penetrates the side plate 53 and the side wall of the tank body 51. The vent 54 mainly allows air to flow between the introduction cylinder 41 and the lubricant tank 50 via the communication pipe 55. When the pressure of the space 30a in the housing rises during operation, the communication pipe 55 also functions as an escape path for air and the like.

[0061] Also refer to Figure 6 and Figure 7 , the connecting tank 60 will be described. Figure 7 It is along Figure 6The connecting tank 60 is a cross-sectional view taken along line AA of the connecting tank 60. The connecting tank 60 has a guide space 60a for storing the lubricant 58, thereby constituting a part of the lubricant tank 50. In addition, the connecting tank 60 functions as a passage for the lubricant 58 that communicates the tank inner space 50a with the shell inner space 30a. The connecting tank 60 has a first side wall portion 61, a second side wall portion 62, and a bottom wall portion 63 that surround the guide space 60a. The first side wall portion 61 and the second side wall portion 62 sandwich the guide space 60a in the width direction, thereby constituting side walls that are opposed to each other. The bottom wall portion 63 constitutes a bottom wall that defines the lower portion of the guide space 60a. The first side wall portion 61 and the second side wall portion 62 extend upward from both ends of the bottom wall portion 63 in the width direction.

[0062] The first side wall 61 and the second side wall 62 are fixed to the introduction tube 41 by welding or the like at their upper sides. The first side wall 61 and the second side wall 62 are fixed to the connecting flange 40 by welding or the like at their input sides, and fixed to the intermediate flange 41f by welding or the like at their opposite input sides.

[0063] The upper side of the guide space 60a is connected to the space 30a in the housing through the supply hole 41h of the housing 30. The input side of the guide space 60a is blocked by the connecting flange 40. The connecting flange 40 is provided with a second connecting hole 40j penetrating in the axial direction, and the input side of the guide space 60a is connected to the tank space 50a of the lubricant tank 50 through the second connecting hole 40j and the first connecting hole 52h of the tank connecting plate 52.

[0064] The lubricant tank 50 has a guide surface 63g for guiding the lubricant 58 to the supply hole 41h of the housing 30 when the posture changes. In the present embodiment, the guide surface 63g is provided on the bottom wall portion 63 of the connecting tank 60. The guide surface 63g is provided as an inclined surface closer to vertical when the second posture changes to the first posture. Figure 6 As shown, in the second posture, when viewed from the side, the guide surface 63g is an inclined surface that inclines downward from the opposite input side toward the input side, and the input side is lower than the opposite input side. That is, in the second posture, the guide surface 63g guides the lubricant 58 from the housing inner space 30a to the tank inner space 50a based on the action of gravity.

[0065] Furthermore, in the first posture, the guide surface 63g is an inclined surface that is inclined toward the central axis La side as it moves from the input side toward the opposite input side, and the opposite input side is lower than the input side. That is, in the first posture, the guide surface 63g guides the lubricant 58 from the tank internal space 50a to the housing internal space 30a based on the action of gravity.

[0066] Next, refer to Figure 1 , Figure 8 and Fig. 9 , the operation of the reduction gear device 100 according to the present embodiment will be described. Figure 8 and Fig. 9 1 is a side view schematically showing the state of the lubricant 58 of the reduction gear 100 in the first posture and the second posture. Figure 8 and Fig. 9 In FIG. 1 , a thick solid line indicates a sealed space for the lubricant 58 , and a thin one-dot chain line mainly indicates a rotating portion of the speed reduction mechanism 10 .

[0067] As the motor 70 rotates, the reduction gear 100 transmits the reduced rotation from the output shaft 14 to the driven component 85 of the driven device 80. The posture of the driven device 80 changes according to the rotation of the driven component 85. The posture of the reduction gear 100 mounted on the driven device 80 changes integrally with the posture change of the driven device 80. At this time, the posture of the reduction gear 100 changes in Figure 8 The first posture shown is Fig. 9 Change between the second posture shown.

[0068] like Figure 8 As shown, in the first posture in which the axial direction is vertical (plumb), the lubricant 58 moves from the tank space 50a to the housing space 30a, and the liquid level L58 of the lubricant 58 is formed to be the height at which the meshing part of the speed reduction mechanism 10 is immersed in the lubricant 58. In this example, it is preferred that the first internal gear 16d located at the uppermost part is immersed in the lubricant 58. As an example, the liquid level L58 of the lubricant 58 is located at a position higher than the first internal gear 16d. At this time, the lubrication of the speed reduction mechanism 10 can be ensured.

[0069] like Fig. 9 As shown, in the second posture in which the axial direction becomes horizontal, the lubricant 58 moves to the tank space 50a and the guide space 60a, and the lubricant 58 exceeding the capacity of these spaces remains in the housing space 30a. In the second posture, the liquid level L58 of the lubricant 58 is formed to a height at which a part of the bearing arranged between the planetary gear and the planetary pin is immersed in the lubricant 58 when each planetary gear is located at the lowest position in the vertical direction. In this example, it is preferred that at least a part of the bearing arranged between the first planetary gear 17p and the first planetary pin 16b when the first planetary gear 17p closest to the central axis La is located at the lowest position in the vertical direction is immersed in the lubricant 58. As an example, the liquid level L58 of the lubricant 58 is located at a position higher than at least one rolling element of the bearing arranged between the first planetary gear 17p and the first planetary pin 16b. At this time, the lubrication of the speed reduction mechanism 10 can be ensured.

[0070] In the first and second positions, the liquid level L58 of the lubricant 58 may be located below the input side oil seal 68s. In this case, leakage of the lubricant 58 from the input side oil seal 68s is reduced, and a space above the liquid level L58 can be ensured.

[0071] Next, the features of the reduction gear 100 of the present embodiment having the above structure are described. According to the present embodiment, when changing from the first posture to the second posture, the lubricant 58 in the housing 30 is withdrawn into the lubricant tank 50, and when changing from the second posture to the first posture, the lubricant 58 in the lubricant tank 50 is supplied to the housing 30, so that the lubrication of the reduction gear 10 can be easily ensured.

[0072] Furthermore, since the second posture is a posture in which the axial direction of the reduction mechanism 10 is closer to the horizontal direction than the first posture, the posture change range of the reduction device 100 can be set wider. Furthermore, the housing 30 has a supply hole 41h at a position closer to the input side than the reduction mechanism 10, and the supply hole 41h is connected to the tank space 50a of the lubricant tank 50. Therefore, when the lubricant tank 50 is arranged at a position closer to the input side than the reduction mechanism 10, the lubricant 58 can be evacuated and supplied based on the action of gravity.

[0073] Furthermore, since the guide surface 63g becomes an inclined surface closer to vertical when changing from the second posture to the first posture, the guide surface 63g becomes lower from the movement source of the lubricant 58 toward the movement destination, and the movement of the lubricant 58 becomes smooth.

[0074] Furthermore, the lubricant tank 50 includes the tank body 51 disposed on the motor 70 side of the connection flange 40 and the connection tank 60 disposed on the speed reduction device 100 side of the connection flange 40, so that the total capacity of the lubricant tank 50 can be increased. Furthermore, the tank body 51 and the connection tank 60 are connected to each other through the communication hole 40j provided in the connection flange 40, so that the connection tank 60 can be used as a passage.

[0075] Furthermore, the reduction gear 100 is mounted on the driven device 80 and its posture changes between the first posture and the second posture according to the operation of the driven device 80, so the transmission mechanism therebetween can be simplified. As a result, it is advantageous to reduce the size and weight of the entire device.

[0076] The examples of the embodiments of the present invention are described in detail above. The above embodiments are only specific examples for implementing the present invention. The contents of the embodiments are not intended to limit the technical scope of the present invention. Various design changes such as changes, additions, and deletions of constituent elements can be made without departing from the scope of the inventive concept specified in the technical solution. In the above embodiments, the contents that can be changed in design are explained by adding expressions such as "implementation mode" and "in the implementation mode", but it does not mean that design changes are not allowed without such expressions.

[0077] [Modifications]

[0078] In the drawings and description of the modified examples, the same reference numerals are used for the same or equivalent components and parts as those in the embodiment. The descriptions that overlap with the embodiment are appropriately omitted, and the description focuses on the structures that are different from the embodiment.

[0079] In the description of the embodiment, an example is shown in which the first posture is 90° inclined in the axial direction and the second posture is 0° inclined in the axial direction, but the present invention is not limited thereto. The first posture may be a posture in which the axial direction is inclined larger than the second posture.

[0080] In the description of the embodiment, an example is shown in which the reduction mechanism 10 is composed of a simple planetary gear mechanism, but the reduction mechanism 10 can also be composed of a reduction mechanism based on other principles instead of a simple planetary gear mechanism, or can be composed of a combination of reduction mechanisms based on different principles. In addition, the reduction mechanism 10 is not limited to a reduction mechanism having gears, and can also be a traction drive, for example.

[0081] In the description of the embodiment, an example is shown in which the reduction mechanism 10 is composed of four-stage reduction mechanisms, but the number of stages of the reduction mechanisms is not limited, and the reduction mechanism 10 may be composed of three or fewer stages or five or more stages.

[0082] In the description of the embodiment, an example in which the connecting tank 60 is provided is shown, but a passage member such as a pipe that communicates the lubricant tank 50 and the housing 30 may be provided instead of the connecting tank 60 .

[0083] In the description of the embodiment, an example is shown in which the reduction mechanism 10 is composed of reduction gears arranged on the central axis La, but the reduction mechanism 10 may include reduction gears arranged at positions offset from each other.

[0084] The above-mentioned modifications can also achieve the same effects as those of the embodiment.

[0085] Any combination of the above-described embodiments and modifications is also effective as an embodiment of the present invention. A new embodiment generated by the combination has the effects of the combined embodiments and modifications.

Claims

1. A reduction gear comprising a housing, a reduction mechanism contained in the housing, and a lubricant contained in the housing, wherein the reduction gear is characterized in that: A lubricant tank is further provided, the lubricant tank being in communication with the space in the housing, and the lubricant can flow between the lubricant tank and the space in the housing, When changing from the first posture to the second posture, the lubricant in the housing is withdrawn into the lubricant tank, and when changing from the second posture to the first posture, the lubricant in the lubricant tank is supplied into the housing; The reduction gear is mounted on the driven device, and its posture changes between the first posture and the second posture according to the operation of the driven device. The second posture is a posture in which the axial direction of the speed reduction mechanism is closer to the horizontal direction than in the first posture.

2. A reduction gear comprising a housing, a reduction mechanism contained in the housing, and a lubricant contained in the housing, wherein the reduction gear is characterized in that: A lubricant tank is further provided, the lubricant tank being in communication with the space in the housing, and the lubricant can flow between the lubricant tank and the space in the housing, When changing from the first posture to the second posture, the lubricant in the housing is withdrawn into the lubricant tank, and when changing from the second posture to the first posture, the lubricant in the lubricant tank is supplied into the housing; The housing has a supply hole at a position closer to the input side than the speed reduction mechanism, and the supply hole is connected to the space in the lubricant tank; The lubricant tank has a guide surface for guiding the lubricant toward the supply hole of the housing, and the guide surface is formed as an inclined surface closer to vertical when changing from the second posture to the first posture.

3. A reduction gear comprising a housing, a reduction mechanism contained in the housing, and a lubricant contained in the housing, wherein: A lubricant tank is further provided, the lubricant tank being in communication with the space in the housing, and the lubricant can flow between the lubricant tank and the space in the housing, When changing from the first posture to the second posture, the lubricant in the housing is withdrawn into the lubricant tank, and when changing from the second posture to the first posture, the lubricant in the lubricant tank is supplied into the housing; It also has a connecting flange for connecting the motor and the reduction device. The lubricant tank has a tank body arranged on the motor side of the connecting flange and a connecting tank arranged on the reduction device side of the connecting flange. The tank body and the connecting tank are connected to each other through a connecting hole set in the connecting flange.

4. The reduction gear device according to claim 2 or 3, characterized in that: The second posture is a posture in which the axial direction of the speed reduction mechanism is closer to the horizontal direction than in the first posture.

Images