WO2014087573A1

WO2014087573A1 - Gear device

Info

Publication number: WO2014087573A1
Application number: PCT/JP2013/006433
Authority: WO
Inventors: 俊介吉田; 和哉古田
Original assignee: ナブテスコ株式会社
Priority date: 2012-12-03
Filing date: 2013-10-30
Publication date: 2014-06-12
Also published as: KR20150075110A; CN104838171A; TW201430238A; KR101732287B1; JP2014109323A; DE112013005765T5

Abstract

The gear device (1) is provided with: an outer tube (2); a crank shaft (20); a carrier (4) that supports the crank shaft (20) to rotate freely and rotates relative to the outer tube (2) in cooperation with the rotation of the crank shaft (20); an oil seal (61); and an O-ring (62). The carrier (4) has a base plate (32a) and a flange (32c) that protrudes radially outward from the outer circumference of the base plate (32a) and is disposed next to the outer tube (2) in the axial direction. On the inside of the outer tube (2), the oil seal (61) is interposed in a first gap (63), which is a gap between the carrier (4) and the outer tube (2), and prevents the leakage of a lubricant inside the outer tube (2). The O-ring (62) seals a second gap (64), which is a gap between the flange (32c) and the outer tube (2) in communication with the first gap (63), and prevents the intrusion of foreign matter into the second gap (64).

Description

Gear device

The present invention relates to a gear device.

Conventionally, an eccentric oscillating gear device that is used by being fixed between a pair of counterpart members such as an industrial robot, and includes an outer cylinder that can be fixed to one counterpart member, a crankshaft, and the other A gear device including a carrier that can be fixed to a counterpart member is known. The carrier is stored inside the outer cylinder. The carrier rotates relative to the outer cylinder in conjunction with the rotation of the crankshaft.

In such an eccentric oscillating gear device, in order to improve the transmission torque between a pair of mating members, as described in Patent Documents 1 and 2, it is fixed to any one of the mating members. A flange portion that extends to the vicinity of the outer diameter of the outer cylinder is formed on the end surface of the carrier to be formed, a female screw hole is formed in the flange portion, and the female screw hole is used to fasten to the mating member with a bolt. The structure is known.

Also, in such an eccentric oscillating gear device, an oil seal is provided in the gap in order to prevent leakage of the lubricant from the gap between the carrier and the outer cylinder. For example, as described in Patent Document 3, the oil seal includes an oil lip that seals the gap in a liquid-tight manner to prevent leakage of the lubricant, and a foreign matter that has entered the gap from the outside. It is generally known that it has a dust lip that prevents it from reaching.

In the structures described in Patent Documents 1 and 2 above, a gap that is open to the outside is formed between the flange portion of the carrier and the end surface of the outer cylinder. For this reason, foreign matter enters from the outside through this gap, making it difficult to get out of the space where the oil seal is arranged. As a result, the foreign matter may damage the oil lip that seals the lubricant in the oil seal, causing problems such as leakage of the lubricant in the gear device.

Therefore, two oil seals are arranged side by side in the axial direction or an oil seal with a dust lip as described in Patent Document 3 is used to prevent foreign matter from reaching the oil lip. I need it. In these cases, the oil seal becomes longer in the axial direction of the gear device. For this reason, the entire gear device becomes longer in the axial direction, making it difficult to reduce the thickness of the gear device.

JP 2006-144888 A JP 56-39341 A JP 2009-109002 A

An object of the present invention is to provide a gear device capable of shortening the width of a sealing member for sealing a lubricant and preventing foreign matter from entering the outer cylinder.

A gear device according to the present invention is a gear device for transmitting a rotational force between a pair of mating members at a predetermined reduction ratio, an outer cylinder that can be fixed to one mating member, a crankshaft, A carrier that is rotatably supported inside an outer cylinder, rotatably supports the crankshaft, and rotates relative to the outer cylinder in conjunction with the rotation of the crankshaft. A flange portion that protrudes radially outward from the outer periphery of the outer cylinder, and is arranged in an axial direction with the outer cylinder, so that at least one of the substrate portion and the flange portion can be fixed to the other counterpart member. A lubricant seal member configured to prevent leakage of lubricant inside the outer cylinder by being interposed in a first gap, which is a gap between the carrier and the outer cylinder, on the inner side of the outer cylinder, Before communicating with the first gap The second gap is a gap between the flange portion and the outer tube sealing, is characterized by comprising a foreign matter seal member for preventing foreign material from entering the said second gap, a.

It is sectional drawing of the gear apparatus which concerns on embodiment of this invention. It is an expanded sectional view which shows arrangement | positioning of the oil seal and O-ring of FIG. It is sectional drawing of the gear apparatus which concerns on the modification of embodiment of this invention. FIG. 4 is an enlarged sectional view showing the arrangement of the oil seal and the O-ring in FIG. 3.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

The eccentric oscillating gear device according to the present embodiment is a gear device applied as a speed reducer to, for example, a swivel unit such as a swivel trunk or arm joint of a robot or a swivel unit of various machine tools. In the following description of the present embodiment, an example in which an eccentric oscillating gear device (hereinafter simply referred to as a gear device) is applied to a revolving drum of a robot will be described.

As shown in FIG. 1, this gear device transmits a rotational force by decelerating at a predetermined reduction ratio between a base 50 (one counterpart member) and a revolving body 52 (the other counterpart member). The gear device of the present embodiment includes an outer cylinder 2, an internal tooth pin 3, a carrier 4, a main bearing 6, a spur gear 18, a crankshaft 20, a crank bearing 22, a swing gear 24, An oil seal 61 and an O-ring 62 are provided.

The outer cylinder 2 is a first fixing member that can be fixed to one counterpart member. The outer cylinder 2 functions as a case constituting the outer surface of the gear device. The outer cylinder 2 is formed in a substantially cylindrical shape, and is fastened to, for example, the base 50 fixed on the installation surface. On the inner surface of the outer cylinder 2, a large number of internal tooth pins 3 are arranged at equal intervals in the circumferential direction. The internal tooth pin 3 functions as an internal tooth with which a swing gear 24 made of an external gear meshes. The number of teeth of the oscillating gear 24 is slightly smaller than the number of the internal tooth pins 3. In the present embodiment, two oscillating gears 24 are used, but the number is not limited to two.

The carrier 4 is a second fixing member that can rotate relative to the first fixing member. The carrier 4 is rotatably supported inside the outer cylinder 2 in a state of being coaxially arranged with the outer cylinder 2. The carrier 4 rotates relative to the outer cylinder 2 around the same axis. The carrier 4 is fastened to the revolving body 52 with bolts B <b> 1 and B <b> 2 described later. When the carrier 4 rotates relative to the outer cylinder 2, the revolving body 52 revolves with respect to the base 50.

The carrier 4 is supported so as to be rotatable relative to the outer cylinder 2 by the main bearings 6 provided in a pair apart from each other in the axial direction. The carrier 4 includes a base portion 32 and an end plate portion 34. The base portion 32 and the end plate portion 34 are fastened to each other so as to house the rocking gear 24 between the base portion 32 and the end plate portion 34.

The base portion 32 includes a substrate portion 32a disposed in the outer cylinder 2 in the vicinity of the end portion of the outer cylinder 2, a shaft portion 32b extending in the axial direction from the substrate portion 32a toward the end plate portion 34, and a substrate portion. And a flange portion 32c projecting radially outward from the outer periphery of 32a.

The substrate portion 32a has a flat surface 32a1 opposite to the side on which the shaft 32b extends. The end surface of the swivel body 52 abuts on the flat surface 32a1. Female screw holes 32a2 and 32a3 are formed in the flat surface 32a1. Bolts B1 and B2 for fastening the revolving body 52 to the board portion 32a are screwed into these female screw holes 32a2 and 32a3.

The substrate portion 32a has a facing portion 32a4 facing the inner peripheral surface 2a in the vicinity of the edge of the outer cylinder 2, as shown in FIGS. The facing portion 32a4 faces the entire circumference of the inner peripheral surface 2a of the outer cylinder 2. The outer peripheral surface of the facing portion 32 a 4 is a seal surface 4 a extending in the axial direction C of the carrier 4. The oil lip 61b1 of the oil seal 61 is in close contact with the seal surface 4a. Thereby, the leakage of the lubricant from the gap between the seal surface 4a and the oil lip 61b1 is prevented.

The flange portion 32c protrudes radially outward from the outer periphery of the substrate portion 32a. The flange portion 32 c is arranged side by side with the outer cylinder 2 in the axial direction C. The flange portion 32 c is arranged side by side in the axial direction C with the facing portion 32 a 4 facing the inner peripheral surface 2 a of the outer cylinder 2. By providing the flange portion 32c on the outer periphery of the substrate portion 32a, the rigidity on the outer periphery side of the substrate portion 32a is improved, and the positions of the bolts B1 and B2 for fastening the swivel body 52 can be arranged on the outer periphery side of the substrate portion 32a. It becomes possible. Thereby, the transmission torque of the gear apparatus 1 improves.

As shown in FIG. 2, a first gap 63 is formed between the seal surface 4 a extending in the axial direction C of the carrier 4 and the inner peripheral surface 2 a of the outer cylinder 2 inside the outer cylinder 2. . Further, a second gap 64 is formed between the end face 32 c 1 of the flange portion 32 c and the end face 2 b of the outer cylinder 2 facing each other in the axial direction C so as to communicate with the first gap 63. The second gap 64 allows communication between the first gap 63 and the outside of the outer cylinder 2.

The shaft portion 32b is fastened to the end plate portion 34 by a bolt 5 having a head portion 5a and a male screw portion 5b continuous with an end surface of the head portion 5a. Thereby, the base 32 and the end plate part 34 are integrated. In other words, the first coupling hole 34 a is formed in the end plate portion 34 so as to penetrate in the thickness direction of the end plate portion 34. The first coupling hole 34a is a stepped hole having a large diameter portion and a small diameter portion. The head 5a of the bolt 5 is disposed in the large diameter portion of the first coupling hole 34a.

A positioning hole 32d and a second coupling hole 32e are formed on the front end surface of the shaft portion 32b (the contact surface with the end plate portion 34). A pin 36 is press-fitted into the positioning hole 32d. By inserting the pin 36 inserted into the pin hole 34b of the end plate portion 34 into the positioning hole 32d, the end plate portion 34 is positioned with respect to the base portion 32. On the other hand, the second coupling hole 32e is constituted by a screw hole, and the male thread portion 5b of the bolt 5 inserted through the first coupling hole 34a is screwed into the second coupling hole 32e. The base portion 32 and the end plate portion 34 are coupled to each other by the bolt 5.

The oil seal 61 is interposed inside the outer cylinder 2 in a first gap 63 that is a gap between the carrier 4 and the outer cylinder 2 to prevent leakage of the lubricant inside the outer cylinder 2. The oil seal 61 is included in the concept of the lubricant seal member of the present invention. The first gap 63 is formed along the inner peripheral surface 2a of the outer cylinder 2 and has a ring shape. The oil seal 61 is disposed along the entire circumference of the first gap 63.

The oil seal 61 has a ring shape so as to be sealed over the entire circumference of the first gap 63. Specifically, as shown in FIG. 2, the oil seal 61 includes a base portion 61a fitted into the inner peripheral surface 2a of the outer cylinder 2, and a seal portion 61b connected to the base portion 61a.

The base portion 61a includes an elastic body portion 61a1 such as nitrile rubber and a metal-made reinforcing ring 61a2 having an L-shaped cross section that reinforces the elastic body portion 61a1.

The seal portion 61b includes an oil lip 61b1 made of an elastic material such as nitrile rubber, and a coil spring 61b2 that presses the oil lip 61b1 inward (in the radial direction). The oil lip 61b1 is formed integrally with the elastic body portion 61a1 of the base portion 61a. The coil spring 61b2 extends in a ring shape around the axial direction C.

The oil lip 61b1 has a convex portion 61b3 on the side facing the seal surface 4a.

The oil lip 61b1 is pressed toward the seal surface 4a extending in the axial direction C of the carrier 4 by the pressing force of the coil spring 61b2. As a result, the convex portion 61b3 is pressed against the seal surface 4a of the carrier 4, and the state of being in close contact with the seal surface 4a is maintained. Accordingly, it is possible to prevent the lubricant from leaking from the first gap 63 to the outside of the outer cylinder 2 through the second gap 64.

The O-ring 62 seals the second gap 64 that is a gap between the flange portion 32 c and the outer cylinder 2. This prevents foreign matter from entering the first gap 63 communicating with the second gap 64. The O-ring 62 is made of a ring-shaped elastic member and is made of fluorine rubber, nitrile rubber, or the like. The cross-sectional shape of the O-ring 62 is not limited to a circular cross section or an elliptical cross section, but may be various cross-sectional shapes. However, it is preferable that the O-ring 62 has a circular cross-sectional shape because the O-ring 62 can securely adhere to the inside of the groove 65 in accordance with the shape of the groove 65 to be described later and ensure sealing performance. The O-ring 62 is included in the concept of the foreign matter sealing member of the present invention.

As shown in FIG. 2, a V-shaped groove 65 that extends in the circumferential direction of the outer cylinder 2 and receives the O-ring 62 is formed at the inlet opening on the outer peripheral side of the outer cylinder 2 in the second gap 64. ing. The groove 65 has a width wider than the width of the second gap 64. The O-ring 62 is inserted into the groove 65.

In the present embodiment, a groove formed in a V shape using the chamfered portions of the outer cylinder 2 and the flange portion is employed as the groove 65. In addition, this invention is not limited to this, You may form a groove | channel other than a chamfering part.

A plurality of the crankshafts 20 are provided. The crankshafts 20 are arranged at equal intervals in the circumferential direction around the central through hole 4b that penetrates the center of the carrier 4 in the axial direction. A spur gear 18 is attached to the end of each crankshaft 20. The spur gear 18 meshes with a drive gear (not shown) driven by a drive source (motor) (not shown). Each spur gear 18 transmits the rotation of the drive gear to the crankshaft 20 to which the spur gear 18 is attached. That is, the spur gear 18 functions as an input unit to which driving force for rotating the crankshaft 20 is input from a driving source.

Each crankshaft 20 is attached to the carrier 4 via a pair of crank bearings 22 so as to be rotatable around the axis. That is, the crankshaft 20 is rotatably supported by the carrier 4.

The crankshaft 20 has a shaft main body 20b and a plurality (two in this embodiment) of eccentric portions 20a formed integrally with the shaft main body 20b. The plurality of eccentric portions 20 a are arranged so as to be aligned in the axial direction at a position between the pair of crank bearings 22. The eccentric portions 20a are each formed in a cylindrical shape that is eccentric from the axis of the shaft main body 20b of the crankshaft 20 by a predetermined amount of eccentricity. And each eccentric part 20a is formed in the crankshaft 20 so that it may have a phase difference of a predetermined angle mutually. In this embodiment, it has a phase difference of 180 degrees.

The rocking gear 24 is attached to the eccentric portion 20a of the crankshaft 20 via an eccentric portion bearing 28, and is disposed so as to be sandwiched between the substrate portion 32a and the end plate portion 34 in the carrier 4. Yes. The oscillating gear 24 is formed to be slightly smaller than the inner diameter of the outer cylinder 2 and meshes with the internal tooth pin 3 on the inner surface of the outer cylinder 2 in conjunction with the eccentric rotation of the eccentric portion 20a when the crankshaft 20 rotates. Oscillates and rotates.

The oscillating gear 24 has a plurality of eccentric part insertion holes 24c and a plurality of shaft part insertion holes 24d. In the illustrated example, the oscillating gear 24 having a through hole 24b formed in the center is shown, but the central through hole 24b can be omitted.

The eccentric portion insertion holes 24 c are provided at equal intervals in the circumferential direction around the central through hole 24 b in the swing gear 24. The eccentric portion 20a of each crankshaft 20 is inserted into each eccentric portion insertion hole 24c with the eccentric portion bearing 28 interposed therebetween.

Each eccentric part 20a is fitted with an eccentric part bearing 28, and a pair of

washers

30 and 30 are fitted to the shaft body 20b of the crankshaft 20 so as to sandwich the eccentric part bearing 28 therebetween. Each washer 30 is sandwiched between the crank bearing 22 and the eccentric portion 20a. Both crank

bearings

22 and 22 are fixed by a retaining ring 31 so as not to be displaced with respect to the substrate portion 32 a and the end plate portion 34.

The shaft portion insertion holes 24d are provided at equal intervals in the circumferential direction around the central through hole 24b in the swing gear 24. Each shaft portion insertion hole 24d is disposed at a position between the eccentric portion insertion holes 24c in the circumferential direction. In each shaft portion insertion hole 24d, the shaft portion 32b is inserted in a state where a gap is left between the shaft portion 32b and the outer peripheral surface of the shaft portion 32b of the carrier 4.

The eccentric part bearing 28 is constituted by a radial roller bearing having a plurality of rolling elements 42 and a cage 44 for holding the rolling elements 42.

Next, the operation of the gear device according to the present embodiment will be described.

When each spur gear 18 receives a rotational driving force from a driving source (not shown), each spur gear 18 rotates around its axis to rotate each crankshaft 20. As a result, the

eccentric parts

20a, 20a of the crankshaft 20 are eccentrically rotated, so that the oscillating gears 24, 24 are interlocked with the eccentric rotation of the

eccentric parts

20a, 20a, and the internal teeth pins 3, 3 on the inner surface of the outer cylinder 2. Oscillates while meshing with. The swing rotation of the swing gear 24 is transmitted to the carrier 4 through each crankshaft 20. As a result, the carrier 4 and the revolving structure 52 rotate relative to the outer cylinder 2 and the base 50 at a rotational speed decelerated from the input rotation. The crankshaft 20 can rotate forward and backward, and the rotation direction of the carrier 4 is determined according to which direction the crankshaft 20 rotates.

When the carrier 4 rotates relative to the outer cylinder 2 as described above, in the first gap 63 between the carrier 4 and the outer cylinder 2, the oil lip 61b1 of the oil seal 61 is moved by the coil spring 61b2. Since the state pressed against the seal surface 4a is maintained, leakage of the lubricant is prevented. In addition, the entrance of the second gap 64 between the flange portion 32c of the carrier 4 and the outer cylinder 2 is closed by an O-ring 62 fitted in a V-shaped groove 65 formed at the entrance. Foreign matter is prevented from entering the first gap 63 inside the outer cylinder 2 through the second gap 64.

As described above, in the gear device 1 of the present embodiment, the second gap 64 between the flange portion 32c of the carrier 4 and the outer cylinder 2 has the carrier 4 and the outer cylinder 2 in which the oil seal 61 inside the outer cylinder is interposed. The O-ring 62 that functions as a foreign matter sealing member is interposed in the second gap 64. Therefore, the O-ring 62 can prevent foreign matter from entering from the second gap 64. Thereby, the oil seal 61 that is interposed in the first gap 63 inside the outer cylinder 2 and functions as a lubricant seal member does not need a portion such as a dust lip for preventing foreign matter from entering. Thereby, the axial width of the oil seal 61 can be shortened (that is, flattened), and foreign matter can be prevented from entering the outer cylinder 2. As a result, the entire width of the gear device can be reduced, and the gear device can be reduced in thickness.

Further, in the gear device 1 according to the present embodiment, the O-ring 62 extends in the circumferential direction of the outer cylinder 2 and is inserted into the groove 65 that receives the O-ring 62. The gap 64 can be reliably sealed. Moreover, since the groove | channel formed in V shape using the chamfering part of the outer cylinder 2 and a flange part is utilized as the groove | channel 65 in which the O-ring 62 is engage | inserted, it can reduce the effort of a process. Is possible.

Moreover, since the V-shaped groove 65 is exposed to the outside from the outer peripheral portion of the outer cylinder 2 and the carrier 4 outside the oil seal 61, the O-ring 62 can be easily formed into the V-shaped groove 65. It is possible to insert. In addition, since the O-ring 62 having a circular cross-sectional shape can be securely attached to the V-shaped groove 65, the sealing performance is also good.

In the above embodiment, the V-shaped groove 65 formed on the outer peripheral side of the outer cylinder 2 and the carrier 4 is formed as the mounting location of the O-ring 62, but the present invention is not limited to this. Instead, the O-ring 62 may be attached to other places as long as the second gap 64 is blocked and foreign matter can be prevented from entering the first gap 63 from the second gap 64.

For example, as a modification of the present invention, as shown in FIGS. 3 to 4, one end surface of the opposing end surfaces of the flange portion 32c and the outer cylinder 2 (the end surface on the carrier 4 side in FIGS. 3 to 4). A groove 66 may be formed in 4b), and an O-ring 62 may be disposed in the groove 66.

3 to 4, the O-ring 62 is located on the inner side of the outer peripheral surface of the outer cylinder 2 and the carrier 4. Therefore, it is possible to suppress the O-ring 62 from coming into contact with an obstacle or the like outside the outer cylinder 2 to be damaged or deteriorated. Moreover, by adjusting the relative position in the axial direction C between the carrier 4 and the outer cylinder 2, the second gap 64 between the flange portion 32 c of the carrier 4 and the outer cylinder 2 is adjusted, and the O-ring 62. It is possible to adjust the crimping force. Therefore, it is possible to make the second gap 64 narrower than in the above embodiment.

In the above embodiment, the oil seal 61 having a configuration in which only the oil lip 61b1 is in contact with the seal surface 4a of the carrier 4 is described as an example of the lubricant seal member of the present invention. However, the present invention is not limited thereto. Is not to be done. As a modified example of the present invention, in addition to the oil lip 61b1, an oil seal having a dust lip that prevents foreign matter from reaching the oil lip 61b1 may be employed. If such an oil seal having a dust lip is employed, it is possible to reliably prevent foreign matter from reaching the oil lip 61b1 by the dust lip together with the O-ring 62. Even in such a case, since the O-ring 62 mainly prevents intrusion of foreign matter from the second gap 64, the dust lip provided on the oil seal can be small and auxiliary. As a result, it is possible to reduce the axial width of the oil seal as compared to a conventional oil seal with a dust strip.

As long as the lubricant seal member of the present invention can seal the lubricant, it is possible to adopt not only the oil seal 61 but also members of various modes.

In the said embodiment, the said 2nd clearance gap 64 is plugged up as a foreign material sealing material which prevents that a foreign material penetrate | invades into the inside of the outer cylinder 2 from the 2nd clearance gap 64 between the flange part 32c of the carrier 4, and the outer cylinder 2. FIG. Although the O-ring 62 is provided, the present invention is not limited to this, and various foreign matter sealing members can be used as long as foreign matter can be prevented from entering the second gap 64. Is possible. For example, a thin rubber packing or a brush-like member is also included in the foreign matter sealing material of the present invention.

In the above-described embodiment, the revolving body 52 that is the counterpart member is fastened with the bolts B1 and B2 to the substrate portion 32a of the base portion 32 of the carrier 4, but the present invention is not limited to this. In the present invention, it is only necessary that the swivel body 52 is fastened with bolts B1 and B2 to at least one of the substrate portion 32a and the surrounding flange portion 32c.

In the above embodiment, the plurality of crankshafts 20 are arranged around the central through hole 4b (see FIG. 1) of the carrier 4, but the present invention is not limited to this. For example, the present invention includes a center crank type gear device in which the crankshaft 20 is disposed at the center of the carrier 4.

The specific embodiments described above mainly include inventions having the following configurations.

The gear device of the present embodiment is a gear device for transmitting a rotational force at a predetermined reduction ratio between a pair of counterpart members, an outer cylinder that can be fixed to one counterpart member, a crankshaft, A carrier that is rotatably supported inside the outer cylinder, rotatably supports the crankshaft, and rotates relative to the outer cylinder in conjunction with the rotation of the crankshaft. A flange portion that protrudes radially outward from the outer periphery of the portion and arranged in the axial direction with the outer cylinder, and at least one of the substrate portion and the flange portion can be fixed to the other counterpart member A lubricant sealing member that prevents leakage of lubricant inside the outer cylinder by being interposed in a first gap, which is a gap between the carrier and the outer cylinder, inside the outer cylinder, Communicate with the first gap Sealing the second gap is a gap between the outer cylinder and the flange portion, is characterized by comprising a foreign matter seal member for preventing foreign material from entering the said second gap, a.

According to such a configuration, in the structure in which the second gap between the flange portion of the carrier and the outer cylinder communicates with the first gap between the carrier and the outer cylinder where the lubricant seal member inside the outer cylinder is interposed, A foreign matter sealing member is interposed in the second gap. Therefore, the foreign substance sealing member can prevent foreign substances from entering from the second gap. As a result, the lubricant seal member interposed in the first gap inside the outer cylinder does not require a portion such as a dust strip for preventing foreign matter from entering. As a result, the axial width of the lubricant seal member can be shortened (that is, flattened), and foreign matter can be prevented from entering the outer cylinder. As a result, the entire width of the gear device can be reduced, and the gear device can be reduced in thickness.

A groove that extends in the circumferential direction of the outer cylinder and receives the foreign material sealing member is formed at an inlet opening on the outer peripheral side of the outer cylinder in the second gap, and the foreign material sealing member is inserted into the groove. May be.

According to this configuration, the foreign matter sealing member extends in the circumferential direction of the outer cylinder and is inserted into the groove that receives the foreign matter sealing member. Therefore, it is possible to prevent the foreign matter sealing member from being displaced and to seal the second gap reliably. Moreover, as the said groove | channel, it is possible to use the groove | channel formed in V shape using each chamfering part of an outer cylinder and a flange part. Therefore, if the above-mentioned chamfered portion is used, it is possible to reduce the trouble of processing the groove.

A groove may be formed in one of end faces of the flange portion and the outer cylinder facing each other, and the seal member may be disposed in the groove.

According to such a configuration, the foreign matter sealing member can be disposed on the inner side of the outer cylinder and the outer peripheral surface of the carrier. Therefore, it is possible to prevent the foreign material sealing material from being damaged or deteriorated by contacting an obstacle or the like outside the outer cylinder. In addition, by adjusting the relative position in the axial direction between the carrier and the outer cylinder, it is possible to adjust the second gap between the flange portion and the outer cylinder and to adjust the pressure-bonding force of the foreign matter sealing member. It is. Therefore, it is possible to make the second gap narrower.

Claims

A gear device for transmitting a rotational force at a predetermined reduction ratio between a pair of counterpart members,
An outer cylinder that can be fixed to one counterpart member;
A crankshaft,
A carrier that is rotatably supported inside the outer cylinder, rotatably supports the crankshaft, and rotates relative to the outer cylinder in conjunction with the rotation of the crankshaft. A flange portion that protrudes radially outward from the outer periphery of the portion and arranged in the axial direction with the outer cylinder, and at least one of the substrate portion and the flange portion can be fixed to the other counterpart member A carrier configured with
Inside the outer cylinder, a lubricant seal member that is interposed in a first gap which is a gap between the carrier and the outer cylinder, and prevents leakage of the lubricant inside the outer cylinder,
A foreign matter sealing member that seals a second gap, which is a gap between the flange portion communicating with the first gap and the outer cylinder, and prevents foreign matter from entering the second gap;
With
A gear device characterized by that.
A groove extending in the circumferential direction of the outer cylinder and receiving the foreign material sealing member is formed at the inlet opening on the outer peripheral side of the outer cylinder in the second gap,
The foreign matter sealing member is inserted into the groove;
The gear device according to claim 1.
A groove is formed on one of the end faces of the flange portion and the outer cylinder facing each other,
The seal member is disposed in the groove,
The gear device according to claim 1.