KR20150075110A

KR20150075110A - Gear device

Info

Publication number: KR20150075110A
Application number: KR1020157013392A
Authority: KR
Inventors: 슌스케 요시다; ?스케 요시다; 가즈야 후루타
Original assignee: 나부테스코 가부시키가이샤
Priority date: 2012-12-03
Filing date: 2013-10-30
Publication date: 2015-07-02
Also published as: WO2014087573A1; CN104838171A; TW201430238A; KR101732287B1; JP2014109323A; DE112013005765T5

Abstract

The gear device 1 includes an outer cylinder 2, a crankshaft 20 and a crankshaft 20 which are rotatably supported and rotatable relative to the outer cylinder 2 in association with rotation of the crankshaft 20, An oil seal 61, and an O-ring 62. The O-ring 62 is provided with an oil seal 61, The carrier 4 has a base portion 32a and a flange portion 32c projecting radially outward from the outer periphery of the base portion 32a and arranged in parallel with the outer cylinder 2 in the axial direction. The oil seal 61 is interposed between the carrier 4 and the outer cylinder 2 and the first gap 63 to prevent leakage of the lubricant in the outer cylinder 2. The O-ring 62 seals the flange portion 32c communicating with the first gap 63 and the second gap 64 which is the gap between the outer cylinder 2 and the second gap 64, Prevent intrusion.

Description

GEAR DEVICE

The present invention relates to a gear device.

Conventionally, an eccentrically oscillating type gear unit fixedly used between a pair of mating members such as industrial robots, has an outer cylinder that can be fixed to one mating member, a crankshaft, and a carrier that can be fixed to the other mating member A gear device is known. The carrier is accommodated in the outer cylinder. The carrier rotates relative to the outer cylinder in association with the rotation of the crankshaft.

In order to improve the transmission torque between the pair of counterpart members in such an eccentrically oscillating type gear unit, as described in Patent Documents 1 and 2, it is preferable that the end face of the carrier fixed to either one of the counterpart members A flange portion extending to the outer diameter of the outer cylinder is formed, a female screw hole is formed in the flange portion, and a bolt is fastened to the mating member using the female screw hole.

In this eccentric oscillatory gear device, an oil seal is provided in the clearance in order to prevent leakage of the lubricant from the gap between the carrier and the outer cylinder. The oil seal, as disclosed in, for example, Patent Document 3, includes an oil lip which seals the clearance fluid-tightly to prevent leakage of the lubricant, and foreign matter that has entered the clearance from the outside to reach the oil lip It is generally known to have a dust lip which prevents dust.

In the structures described in the above Patent Documents 1 and 2, a gap opened to the outside is formed between the flange portion of the carrier and the end face of the outer cylinder. As a result, foreign matter intrudes from the outside through this gap, making it difficult for the oil seal to come out of the space where the oil seal is disposed. This may damage the oil lip sealing the lubricant in the oil seal due to the foreign matter, thereby causing a problem such as leakage of the lubricant in the gear unit.

Therefore, it is necessary to arrange two oil seals side by side in the axial direction, or use an oil seal provided with a dust lip described in Patent Document 3, to take measures to prevent foreign matter from reaching the oil lip. In these cases, the oil seal becomes longer in the axial direction of the gear device. As a result, the entire gear device becomes long in the axial direction, making it difficult to reduce the thickness of the gear device.

Japanese Patent Laid-Open No. 2006-144888 Japanese Patent Application Laid-Open No. 56-39341 Japanese Patent Application Laid-Open No. 2009-109002

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

A gear device according to the present invention is a gear device for transmitting a rotational force between a pair of counterpart members at a predetermined reduction ratio and includes an outer cylinder fixed to one of the counterpart members, a crank shaft, A carrier which rotatably supports the crankshaft and relatively rotates with the rotation of the crankshaft and which is relatively rotatable with respect to the outer cylinder and which is projected radially outward from the outer periphery of the base plate portion and the base plate, Wherein the flange portion of the carrier has at least one of a flange portion and a flange portion which is fixed to the other of the counterpart members and a first gap which is a gap between the carrier and the outer tube, A lubricant seal member interposed between the first gap and the second gap to prevent leakage of the lubricant in the outer cylinder, To seal the barrel of which the flange portion and the gap in the outer sleeve the second clearance, and wherein the foreign matter and a sealing member for preventing ingress of foreign matter in the art of the second gap.

1 is a sectional view of a gear device according to an embodiment of the present invention.
Fig. 2 is an enlarged sectional view showing the arrangement of the oil seal and the O-ring of Fig. 1;
3 is a cross-sectional view of a gear device according to a modification of the embodiment of the present invention.
4 is an enlarged cross-sectional view showing the arrangement of the oil seal and O-ring of Fig. 3;

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

The eccentric oscillation type gear device according to the present embodiment is a gear device applied as a speed reducer to, for example, a turning part of a turning body of a robot, a turning part such as an arm joint, or a turning part of various machine tools. In the following description of this embodiment, an example in which an eccentric oscillation type gear device (hereinafter simply referred to as a gear device) is applied to the turning body of the robot will be described.

This gear device decelerates at a predetermined reduction ratio between the base 50 (one of the counterpart members) and the swivel body 52 (the other counterpart) to transmit the rotational force as shown in Fig. The gear device of the present embodiment is provided with the outer cylinder 2, the inner teeth 3, the carrier 4, the main bearing 6, the spur gear 18, the crankshaft 20, A crankshaft bearing 22, a rocking gear 24, an oil seal 61, and an O-ring 62. As shown in Fig.

The outer cylinder (2) is a first fixing member that can be fixed to one of the mating members. The outer cylinder 2 functions as a case constituting the outer surface of the gear device. The outer tube 2 is formed in a substantially cylindrical shape and fastened to the base 50 fixed on the mounting surface, for example. On the inner surface of the outer cylinder (2), a large number of inner teeth (3) are arranged at regular intervals in the circumferential direction. The inner tooth pin (3) functions as an inner tooth to which the rocking gear (24) composed of the outer gear is engaged. The number of teeth of the swinging gear 24 is slightly smaller than the number of the internal teeth 3. Although two swing gears 24 are used in the present embodiment, the number is not limited to two.

The carrier (4) is a second fixing member that is relatively rotatable with respect to the first fixing member. The carrier 4 is rotatably supported on the inner side of the outer cylinder 2 in a state of being coaxial with the outer cylinder 2. [ The carrier 4 relatively rotates around the same axis with respect to the outer cylinder 2. [ The carrier 4 is fastened to the slewing body 52 with bolts B1 and B2 to be described later and when the carrier 4 rotates relative to the outer cylinder 2, 50).

The carrier (4) is supported so as to be rotatable relative to the outer cylinder (2) by the main bearing (6) provided in a pair and spaced apart in the axial direction. The carrier 4 has 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 to receive the swinging gear 24 between the base portion 32 and the end plate portion 34.

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

The base portion 32a has a flat surface 32a1 on the opposite side to the side on which the shaft 32b extends. The end face of the slewing body 52 contacts the flat face 32a1. On the flat surface 32a1, female screw holes 32a2 and 32a3 are formed. Bolts B1 and B2 for screwing the slewing body 52 to the base plate portion 32a are screwed into these female screw holes 32a2 and 32a3.

The base portion 32a has an opposing portion 32a4 facing the inner circumferential surface 2a in the vicinity of the rim of the outer cylinder 2, as shown in Figs. The opposing portion 32a4 is opposed to the entire circumference of the inner circumferential surface 2a of the outer cylinder 2. [ The outer peripheral surface of the opposing portion 32a4 is a sealing surface 4a 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. Thus, 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 base plate portion 32a. The flange portion 32c is arranged in parallel with the outer cylinder 2 in the axial direction C. The flange portion 32c is arranged side by side in the axial direction C with the facing portion 32a4 facing the inner circumferential surface 2a of the outer cylinder 2. [ By providing the flange portion 32c on the outer periphery of the base portion 32a, rigidity on the outer periphery side of the base portion 32a is improved and the position of the bolts B1, Can be disposed on the outer circumferential side of the outer cylinder 32a. Thereby, the transmission torque of the gear device 1 is improved.

2, between the sealing surface 4a extending in the axial direction C of the carrier 4 and the inner circumferential surface 2a of the outer cylinder 2 on the inner side of the outer cylinder 2, A gap 63 is formed. Between the end face 32c1 of the flange portion 32c facing the axial direction C and the end face 2b of the outer cylinder 2 so as to communicate with the first gap 63, (64) are formed. The second gap 64 allows the first gap 63 to communicate with 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 thread portion 5b continuous to the end face of the head portion 5a. Thereby, the base portion 32 and the end plate portion 34 are integrated. That is, the end plate portion 34 is formed with the first engaging hole 34a so as to penetrate the end plate portion 34 in the thickness direction. The first engaging hole 34a is formed by a stepped hole having a large diameter portion and a small diameter portion. The head portion 5a of the bolt 5 is disposed in the large diameter portion of the first engagement hole 34a.

The positioning hole 32d and the second engaging hole 32e are formed on the distal end face (the contact face with the end plate portion 34) of the shaft portion 32b. The pin 36 is press-fitted into the positioning hole 32d. The pin 36 inserted into the pin hole 34b of the end plate portion 34 is inserted into the positioning hole 32d to thereby position the end plate portion 34 with respect to the base portion 32. [ On the other hand, the second engaging hole 32e is formed by a screw hole. A male threaded portion 5b of the bolt 5 inserted into the first engaging hole 34a is formed in the second engaging hole 32e Threaded. The base portion 32 and the end plate portion 34 are coupled to each other by the bolts 5.

The oil seal 61 intervenes between the carrier 4 and the outer cylinder 2, which is the gap between the carrier 4 and the first gap 63, to prevent the leakage of the lubricant in the outer cylinder 2 . The oil seal 61 is included in the concept of the lubricant seal member of the present invention. The first clearance 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 hermetically sealed over the entire circumference of the first gap 63. 2, the oil seal 61 includes a base portion 61a inserted into the inner circumferential surface 2a of the outer cylinder 2 and a seal portion 61b connected to the base portion 61a. .

The base portion 61a has an elastic body portion 61a1 made of nitrile rubber or the like and a metal reinforcing ring 61a2 having an L-shaped cross section reinforcing the elastic body portion 61a1.

The seal portion 61b has an oil lip 61b1 made of an elastic material such as nitrile rubber and a coil spring 61b2 pressing the oil lip 61b1 inward (radially inward). The oil lip 61b1 is formed integrally with the elastic portion 61a1 of the base portion 61a. The coil spring 61b2 extends in the ring shape around the axis C.

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

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

The O-ring 62 seals the second gap 64, which is the gap between the flange portion 32c and the outer cylinder 2. This prevents foreign matter from intruding into the first gap 63 communicating with the second gap 64. The O-ring 62 is made of a ring-shaped elastic member, and is formed of fluorine rubber, nitrile rubber or the like. The cross-sectional shape of the O-ring 62 may be not only a circular cross section or an elliptic cross section, but also a cross sectional shape of various shapes. However, if the O-ring 62 has a circular cross-sectional shape, it is preferable that the O-ring 62 can securely come into close contact with the inside of the groove 65 in accordance with the shape of the groove 65 to be described later. The O-ring 62 is included in the concept of the foreign matter seal member of the present invention.

As shown in Fig. 2, at an inlet opening on the outer circumferential side of the outer cylinder 2 in the second gap 64, an O-ring 62 extends in the circumferential direction of the outer cylinder 2, A V-shaped groove 65 is formed. 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 this embodiment, as the groove 65, a groove formed in a V-shape using the chamfered portion of each of the outer cylinder 2 and the flange portion is employed. Further, the present invention is not limited to this, and the groove may be formed by other than the chamfered portion.

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

Each of the crankshafts 20 is rotatably mounted on the carrier 4 via a pair of the crankshaft bearings 22 around its axis. That is, the crankshaft 20 is rotatably supported by the carrier 4.

The crankshaft 20 has a shaft body 20b and a plurality of (two in this embodiment) eccentric portions 20a integrally formed with the shaft body 20b. The plurality of eccentric portions 20a are arranged so as to be arranged in the axial direction at positions between the pair of crank bearings 22. [ The eccentric portion 20a is formed in a cylindrical shape eccentrically eccentric to the axis of the shaft body 20b of the crankshaft 20 by a predetermined eccentricity. The eccentric portions 20a are formed on the crankshaft 20 so as to have a phase difference of a predetermined angle with respect to each other. In the present embodiment, it has a phase difference of 180 degrees.

The rocking gear 24 is mounted on the eccentric portion 20a of the crankshaft 20 through an eccentric portion bearing 28. The base portion 32a and the end plate portion 34 of the carrier 4 are engaged with each other, As shown in Fig. The swinging gear 24 is formed to be slightly smaller than the inner diameter of the outer cylinder 2. When the crankshaft 20 rotates, the swinging gear 24 is rotated in conjunction with the eccentric rotation of the eccentric portion 20a, ).

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

The eccentric portion insertion holes 24c are formed at equal intervals in the circumferential direction around the central through hole 24b 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 of the eccentric portions 20a is fitted with an eccentric portion bearing 28. A pair of washers 30 and 30 are provided on the shaft body 20b of the crankshaft 20 so as to sandwich the eccentric portion bearings 28 . Each washer 30 is inserted between the crank bearing 22 and the eccentric portion 20a. The both crank bearings 22 and 22 are fixed by the retaining ring 31 so as not to be displaced with respect to the base plate portion 32a and the end plate portion 34. [

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

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

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

When each of the spur gears 18 receives a rotational driving force from a driving source (not shown), the spur gears 18 rotate around the respective axes to rotate the respective crankshafts 20. As a result, the eccentric portions 20a, 20a of the crankshaft 20 eccentrically rotate, so that the rocking gears 24, 24 move in the direction of eccentric rotation of the eccentric portions 20a, 20a, While being engaged with the internal gear fins (3, 3, ...). The rocking rotation of the rocking gear 24 is transmitted to the carrier 4 through each crankshaft 20. Thereby, the carrier 4 and the swivel body 52 rotate relative to the outer cylinder 2 and the base 50 at the reduced rotation speed from the input rotation. The crankshaft 20 is rotatable in the forward and reverse directions, and the rotational direction of the carrier 4 is determined according to which direction the crankshaft 20 rotates.

The oil lip 61b1 of the oil seal 61 is pressed against the first clearance 63 between the carrier 4 and the outer cylinder 2 when the carrier 4 rotates relative to the outer cylinder 2 as described above, Is kept pressed against the sealing surface 4a of the carrier 4 by the coil spring 61b2 to prevent leakage of the lubricant. The inlet of the second gap 64 between the flange portion 32c of the carrier 4 and the outer cylinder 2 is connected to the O-ring 62 inserted into the V-shaped groove 65 formed in the inlet, So that foreign matter is prevented from entering the first gap 63 in the outer cylinder 2 through the second gap 64. As a result,

The second gap 64 between the flange portion 32c of the carrier 4 and the outer cylinder 2 is formed by the oil seal 61 inside the outer cylinder An O-ring 62 functioning as a foreign matter sealing member is interposed in the second gap 64 in the structure that communicates with the first gap 63 between the interposed carrier 4 and the outer cylinder 2. [ Therefore, the foreign substance can be prevented from intruding from the second gap 64 by the O-ring 62. Thereby, the oil seal 61 interposed in the first gap 63 on the inner side of the outer cylinder 2 and serving as the lubricant seal member prevents the portion of the dust lip or the like It becomes unnecessary. As a result, it is possible to shorten the width of the oil seal 61 in the axial direction (i.e., flatten it) and prevent foreign matter from entering into the outer cylinder 2. As a result, the entire width of the gear device can be reduced, and the gear device can be made thinner.

In the gear device 1 of the present embodiment, since the O-ring 62 extends in the circumferential direction of the outer cylinder 2 and is inserted in the groove 65 for accommodating the O-ring 62, 62 can be prevented from being displaced, and the second gap 64 can be surely sealed. Since the grooves formed in the V-shape using the chamfered portions of the outer tube 2 and the flange portion are used as the grooves 65 into which the O-rings 62 are inserted, it is possible to reduce the labor of the machining Do.

Since the V-shaped groove 65 is a portion exposed to the outside from the outer cylinder 2 and the outer peripheral portion of the carrier 4 on the outer side of the oil seal 61, It is possible to easily insert it into the groove 65 of the shape. Further, the O-ring 62 having a circular cross-sectional shape can be surely brought into tight contact with the V-shaped groove 65, and sealing property is also good.

Although 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 position of the O-ring 62 in the above embodiment, The O-ring 62 may be mounted on the other side of the first gap 63 if the second gap 64 is closed to prevent foreign matter from entering the first gap 63 from the second gap 64 You can.

For example, as shown in Figs. 3 to 4, as a modified example of the present invention, one of the end faces of the flange portion 32c and the opposed end faces of the outer cylinder 2 Grooves 66 may be formed in the grooves 66 on the carrier 4 side and the O rings 62 may be disposed in the grooves 66. [

3 to 4, the O-ring 62 is located on the inner side of the outer circumferential surface of the outer cylinder 2 and the carrier 4. As shown in Fig. Therefore, it is possible to prevent the O-ring 62 from being damaged or deteriorated by coming into contact with an obstacle outside the outer cylinder 2 or the like. The second gap 64 between the flange portion 32c of the carrier 4 and the outer cylinder 2 is adjusted by adjusting the relative positions of the carrier 4 and the outer cylinder 2 in the axial direction C , And the pressing force of the O-ring 62 can be adjusted. Therefore, it is possible to make the second gap 64 narrower as compared with the above embodiment.

In the above embodiment, the oil seal 61 having the structure in which only the oil lip 61b1 contacts the seal surface 4a of the carrier 4 has been described as an example of the lubricant seal member of the present invention. It is not limited thereto. As a modification of the present invention, an oil seal having a dust lip for preventing foreign matter from reaching the oil lip 61b1 may be employed in addition to the oil lip 61b1. When the oil seal having such a dust lip is employed, it is possible to surely prevent the foreign matter from reaching the oil lip 61b1 by the dust lip together with the O-ring 62. [ Even in such a case, the O-ring 62 mainly prevents foreign matter from entering the second gap 64, so that the dust lip provided on the oil seal may be small and auxiliary. As a result, the width of the oil seal in the axial direction can be shortened as compared with the oil seal having the conventional dust lip.

As the lubricant seal member of the present invention, various types of members as well as the oil seal 61 described above can be employed as long as the lubricant can be sealed.

The above embodiment is a foreign matter sealant for preventing foreign matter from entering the inside of the outer cylinder 2 from the second gap 64 between the flange portion 32c of the carrier 4 and the outer cylinder 2, The present invention is not limited to this, and it is also possible to use various forms of the second gap 64 as long as they can prevent foreign matter from entering the second gap 64 It is possible to employ a foreign matter seal member. For example, a packing made of a thin rubber or a brush-shaped member is also included in the foreign matter sealant of the present invention.

In the above embodiment, the slewing body 52, which is the mating member, is fastened to the base portion 32a of the base portion 32 of the carrier 4 with the bolts B1 and B2, but the present invention is not limited to this no. In the present invention, the slewing body 52 may be fastened to at least one of the base portion 32a and the flange portion 32c around the base portion 32a with the bolts B1 and B2.

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 no. 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. [

In addition, the above-described concrete embodiments mainly include inventions having the following constitutions.

The gear device according to the present embodiment is a gear device for transmitting a rotational force between a pair of counterpart members at a predetermined reduction ratio and includes an outer cylinder fixed to one of the counterpart members, a crank shaft, And is rotatably supported by the crankshaft and relatively rotates with respect to the outer cylinder in association with rotation of the crankshaft. The carrier is protruded radially outward from the outer periphery of the base plate portion and the base plate, A carrier having an arranged flange portion, at least one of the base portion and the flange portion being fixable to the other of the counterpart members; and a second portion, which is a gap between the carrier and the outer tube, A lubricant seal member interposed in the gap to prevent leakage of the lubricant in the outer cylinder, To the flange and seals a second gap is a gap in the outer sleeve to be communicated with, and wherein the foreign matter comprises a sealing member for preventing ingress of foreign matter in the art of the second gap.

According to this configuration, in the structure in which the second gap between the flange portion of the carrier and the outer cylinder is communicated with the first gap between the carrier and the outer cylinder in which the lubricant seal member in the outer cylinder is interposed, Is interposed in the gap. As a result, foreign matter can be prevented from entering the second gap by the foreign matter seal member. As a result, the portion of the lubricant seal member interposed in the first gap on the inner side of the outer cylinder does not need dust lip or the like for preventing the foreign matter from intruding. As a result, it is possible to shorten the width in the axial direction of the lubricant seal member (i.e., flattened) and prevent foreign matter from entering into the outer cylinder. As a result, the entire width of the gear device can be reduced, and the gear device can be made thinner.

A groove is formed in an inlet opening on the outer peripheral side of the outer cylinder in the second gap in a circumferential direction of the outer cylinder to receive the foreign matter sealing member and the foreign matter sealing member is inserted into the groove .

According to this configuration, the foreign matter seal member extends in the circumferential direction of the outer cylinder and is inserted into the groove for receiving the foreign matter seal member. As a result, the positional deviation of the foreign matter seal member can be prevented, and the second gap can be reliably sealed. As the groove, it is possible to use a groove formed in a V-shape using each chamfered portion of the outer tube and the flange portion. Therefore, it is possible to reduce the labor of machining the groove by using the chamfered portion.

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

According to such a configuration, the foreign matter seal member can be disposed inside the outer cylinder and the outer peripheral face of the carrier. As a result, it is possible to prevent the foreign matter sealant from being damaged or deteriorated by being brought into contact with an external obstacle or the like on the outer cylinder. It is also possible to adjust the second gap between the flange portion and the outer cylinder and adjust the pressing force of the foreign matter seal member by adjusting the relative position of the carrier and the outer cylinder in the axial direction. Therefore, it is possible to make the second gap narrower.

Claims

A gear device for transmitting a rotational force between a pair of counterpart members at a predetermined reduction ratio,
An outer cylinder which can be fixed to one of the mating members,
A crankshaft,
A carrier rotatably supported in the outer cylinder and rotatably supporting the crankshaft and relatively rotatable with the outer cylinder in conjunction with rotation of the crankshaft, the carrier being projected radially outward from the outer periphery of the base plate and the base plate A carrier having a flange portion arranged side by side in the axial direction and having at least one of the base portion and the flange portion fixed to the other mating member,
A lubricant seal member interposed between the carrier and the outer tube, the lubricant seal member being interposed between the carrier and the outer tube to prevent leakage of the lubricant in the outer tube;
And a foreign matter seal member that seals a second gap which is a gap between the flange portion communicating with the first gap and the external cylinder to prevent foreign matter from entering into the second gap.

The method according to claim 1,
A groove is formed in an inlet opening on the outer peripheral side of the outer cylinder in the second gap so as to extend in the circumferential direction of the outer cylinder to receive the foreign matter sealing member,
And the foreign matter seal member is inserted into the groove.

The method according to claim 1,
A groove is formed in one of the end faces of the flange portion and the opposite end face of the outer cylinder,
And the seal member is disposed in the groove.