JP7660418B2 - Inner races of bearings, rotating equipment, and reducers - Google Patents

Description

The present invention relates to an inner race of a bearing used in a rotating device, the rotating device, and a reducer.

In industrial robots, machine tools, and the like, reducers are used to reduce the rotation of a rotary drive source such as a motor. In rotating equipment such as reducers, an outer cylindrical member may be connected to the outer periphery of an inner member via a bearing so that they can rotate relative to each other (see, for example, Patent Document 1).

In this type of rotating device, a seal member is interposed between the inner member and the outer cylindrical member together with a bearing. In many cases, the seal member is interposed at a position axially outward of the bearing between the inner member and the outer cylindrical member. The seal member seals the space surrounded by the inner member and the outer cylindrical member at a position axially outward of the bearing.

When assembling this type of rotating equipment, the seal member may be attached to the seal retaining surface on the inner member in advance, the inner race of the bearing may be attached to a position adjacent to the seal retaining surface on the inner member, and in this state the outer tubular member may be assembled to the inner member from the axial direction. In this case, when attaching the seal member to the seal retaining surface of the inner member, it is necessary to move the seal member axially onto the seal retaining surface by pushing the inner circumferential surface outward. For this reason, a seal guide surface is provided adjacent to the seal retaining surface of the inner member to smoothly guide the seal member towards the seal retaining surface. The seal guide surface has an outer diameter that tapers toward the seal retaining surface.

JP 2009-36327 A

In the above-mentioned rotating equipment, a tapered seal guide surface is formed adjacent to the seal retaining surface on the inner member. As a result, the axially outer area of the support area for the bearing (inner race) on the inner member is occupied by the seal retaining surface and the tapered seal guide surface, which increases the axial length of the inner member. This is one of the factors that hinders the miniaturization of rotating equipment.

The present invention provides a bearing inner race, a rotating device, and a reducer that can shorten the axial length of the inner member of the rotating device.

The inner race of a bearing in one embodiment of the present invention is a bearing in which a seal member is interposed between an inner member and an outer cylindrical member which are capable of rotating relative to one another, and the inner race of the bearing is positioned adjacent to a seal retaining surface on the inner member which retains the seal member, and is provided with a seal guide surface which guides the seal member to the seal retaining surface.

The seal guide surface may have an outer diameter that gradually increases from an outer periphery of an end portion adjacent to the seal retaining surface toward the side where the seal retaining surface is disposed.

The seal guide surface may be formed as a restricting wall that restricts displacement of the rolling elements of the bearing at an end portion adjacent to the seal retaining surface in the axial direction of the relative rotation axis of the inner member and the outer cylindrical member.

A rotating device according to one embodiment of the present invention comprises an inner member having a seal retaining surface, an outer tube member arranged rotatably relative to the outer periphery of the inner member, a seal member interposed between the inner member and the outer tube member, and a bearing interposed between the inner member and the outer tube member alongside the seal member along an axial direction, which is the direction in which the relative rotation axis of the inner member and the outer tube member extends, wherein the bearing comprises an inner race arranged adjacent to the seal retaining surface on the inner member on the axial side of the sealed space, and the inner race has a seal guide surface that guides the seal member to the seal retaining surface.

The seal guide surface may have an outer diameter that gradually increases from an outer periphery of an end portion adjacent to the seal retaining surface in the axial direction toward the side where the seal retaining surface is disposed.
The bearing may further include a rolling element, and the inner race may include a regulating wall at an end portion adjacent to the seal retaining surface in the axial direction for regulating displacement of the rolling element, and the seal guide surface may be formed on the regulating wall.

A protection mechanism for preventing damage to the inner peripheral surface of the seal member may be provided between the seal retaining surface and the seal guide surface.

A reducer according to one embodiment of the present invention comprises an inner member having a seal retaining surface, an outer tube member arranged rotatably relative to the outer periphery of the inner member, an input member to which a rotational driving force is input, a reduction mechanism for reducing the speed of the rotational driving force input to the input member and transmitting it to the inner member or the outer tube member, a seal member interposed between the inner member and the outer tube member, and a bearing interposed alongside the seal member along an axial direction, which is the direction in which the relative rotation axis of the inner member and the outer tube member extends, wherein the bearing comprises an inner race arranged adjacent to the seal retaining surface on the inner member on the axial side of the sealed space, and the inner race comprises a seal guide surface for guiding the seal member to the seal retaining surface.

The seal guide surface may have an outer diameter that gradually increases from an outer periphery of an end portion adjacent to the seal retaining surface in the axial direction toward the side where the seal retaining surface is disposed.

A rotating device according to another aspect of the present invention comprises an inner member, an outer tube member arranged rotatably relative to the outer periphery of the inner member, a sealing mechanism for maintaining a sealed space between the inner member and the outer tube member, and a bearing interposed between the inner member and the outer tube member, wherein the bearing comprises an inner race, and the sealing mechanism comprises a first sealing member for sealing the space between the outer periphery of the inner race and the outer tube member, and a second sealing member for sealing the space between the inner race and the inner member.

The inner race may include a seal retaining surface that retains the first seal member, and a seal guide surface whose outer diameter gradually expands toward the seal retaining surface in an axial direction, which is the direction in which the relative rotation axis of the inner member and the outer tube member extends.

The bearing may further include a rolling element, the inner race may include a regulating wall at a position adjacent to the seal retaining surface in the axial direction for regulating displacement of the rolling element, and the seal guide surface may be formed on the regulating wall.

A reducer according to another aspect of the present invention comprises an inner member having a seal retaining surface, an outer tube member arranged rotatably relative to the outer periphery of the inner member, an input member to which a rotational driving force is input, a reduction mechanism for reducing the speed of the rotational driving force input to the input member and transmitting it to the inner member or the outer tube member, a sealing mechanism for maintaining a sealed space between the inner member and the outer tube member tightly, and a bearing interposed between the inner member and the outer tube member, wherein the bearing comprises an inner race, and the sealing mechanism comprises a first sealing member for sealing the space between the outer periphery of the inner race and the outer tube member, and a second sealing member for sealing the space between the inner race and the inner member.

Since the inner race of the bearing described above has a seal guide surface on the outer periphery of the end portion adjacent to the seal retaining surface in the axial direction, the axial length of the inner member can be shortened compared to when a seal guide surface is provided at a position adjacent to the seal retaining surface on the inner member. Therefore, a rotating device that uses the inner race of the bearing described above can be made more compact.
Furthermore, in each of the above-described rotating devices, since the seal guide surface is not provided at a position adjacent to the seal retaining surface on the inner member, the axial length of the inner member can be shortened, and therefore the rotating device can be made smaller.

FIG. 2 is a vertical cross-sectional view of the reducer according to the first embodiment. FIG. 2 is an enlarged cross-sectional view of a portion II in FIG. FIG. 3 is an enlarged cross-sectional view similar to FIG. 2 of a first modified example. FIG. 4 is an enlarged cross-sectional view similar to FIG. 2 of a second modified example. FIG. 5 is an enlarged cross-sectional view similar to FIG. 2 of a reducer according to a second embodiment.

Next, an embodiment of the present invention will be described with reference to the drawings. Note that in each embodiment and modified example described below, the same reference numerals will be used to designate common parts, and some overlapping descriptions will be omitted.

First Embodiment
First, the first embodiment shown in FIG. 1 and FIG. 2 will be described.
FIG. 1 is a cross-sectional view of a rotating device that employs an inner race of a bearing according to this embodiment.
The rotating device of this embodiment is a reducer 10 used in industrial robots, machine tools, etc. Power is transmitted to an input portion (crankshaft 14) of the reducer 10 from an electric motor (not shown) that serves as a rotational drive source.

The reducer 10 includes an outer cylindrical member 11 that also serves as a reducer case, a first carrier block 13A and a second carrier block 13B rotatably held on the inner peripheral surface of the outer cylindrical member 11, a plurality (e.g., three) crankshafts 14 (input members) rotatably supported by the first carrier block 13A and the second carrier block 13B, and a first oscillating gear 15A and a second oscillating gear 15B that oscillate and rotate (orbit) together with two eccentric portions (not shown) of each crankshaft 14. In this embodiment, the first carrier block 13A and the second carrier block 13B constitute the inner member.
For convenience of explanation, the direction along the rotation center axis c1 of the first and second carrier blocks 13A, 13B (the relative rotation axis between the inner member and the outer tube member 11) will be referred to as the axial direction, and the direction extending radially from the rotation center axis c1 will be referred to as the radial direction. The center side of the first and second carrier blocks 13A, 13B in the axial direction will be referred to as the axial inner side, and the opposite side of the axial inner side in the axial direction will be referred to as the axial outer side. Furthermore, the side facing the rotation center axis c1 in the radial direction will be referred to as the radial inner side, and the opposite side of the radial inner side in the radial direction will be referred to as the radial outer side.

The first carrier block 13A has a perforated disk-shaped base plate portion 13Aa and multiple support pillar portions 13Ab extending from the axially inner end face of the base plate portion 13Aa toward the second carrier block 13B. The second carrier block 13B is formed in a perforated disk shape. The end faces of the support pillar portions 13Ab of the first carrier block 13A are butted against the end faces of the second carrier block 13B, and each support pillar portion 13Ab is fastened and fixed to the second carrier block 13B by a bolt 16.

An axial gap (space) is provided between the base plate portion 13Aa of the first carrier block 13A and the second carrier block 13B. A first oscillating gear 15A and a second oscillating gear 15B are disposed in this gap.
The first oscillating gear 15A and the second oscillating gear 15B are formed with escape holes 19 through which the support pillars 13Ab of the first carrier block 13A pass. The escape holes 19 are formed with an inner diameter sufficiently large relative to the support pillars 13Ab so that the support pillars 13Ab do not interfere with the oscillating motion (turning motion) of the first oscillating gear 15A and the second oscillating gear 15B.

The outer tube member 11 is disposed across the outer peripheral surface of the base plate portion 13Aa of the first carrier block 13A and the outer peripheral surface of the second carrier block 13B. The outer peripheral surface of the base plate portion 13Aa of the first carrier block 13A and the outer peripheral surface of the second carrier block 13B are rotatably supported via bearings 12A and 12B on the inner peripheral portions on both sides of the axial direction of the outer tube member 11. In addition, a plurality of pin grooves 17 extending parallel to the rotation center axis c1 of the first and second carrier blocks 13A and 13B are formed on the inner peripheral surface of the central region in the axial direction of the outer tube member 11 (the region facing the outer peripheral surfaces of the first oscillating gear 15A and the second oscillating gear 15B). Each pin groove 17 rotatably accommodates an approximately cylindrical internal tooth pin 20. A number of internal tooth pins 20 attached to the inner peripheral surface of the outer tubular member 11 face the outer peripheral surfaces of the first oscillating gear 15A and the second oscillating gear 15B.

The first oscillating gear 15A and the second oscillating gear 15B are formed with an outer diameter slightly smaller than the inner diameter of the outer tube member 11. External teeth 15Aa, 15Ba are formed on the outer peripheral surfaces of the first oscillating gear 15A and the second oscillating gear 15B, which are in meshing contact with a plurality of internal tooth pins 20 arranged on the inner peripheral surface of the outer tube member 11. The number of teeth of the external teeth 15Aa, 15Ba formed on the outer peripheral surfaces of the first oscillating gear 15A and the second oscillating gear 15B is set to be slightly less (e.g., one less) than the number of internal tooth pins 20.

The crankshafts 14 are arranged on the same circumference centered on the central axis c1 of the rotation of the first carrier block 13A and the second carrier block 13B. Each crankshaft 14 is rotatably supported by the first carrier block 13A and the second carrier block 13B via bearings (not shown). The two eccentric parts of each crankshaft 14 penetrate the first oscillating gear 15A and the second oscillating gear 15B, respectively. Each eccentric part is rotatably assembled to a support hole formed in the first oscillating gear 15A and the second oscillating gear 15B, respectively, via an eccentric part bearing (not shown). The two eccentric parts of each crankshaft 14 are eccentric so that their phases are shifted by 180° from each other around the central axis of the crankshaft 14.

When the crankshafts 14 rotate in one direction by the power of an electric motor (not shown), the eccentric portion of the crankshafts 14 revolves in the same direction at a predetermined radius, and the first oscillating gear 15A and the second oscillating gear 15B revolve (turn) in the same direction at the same radius. At this time, the external teeth 15Aa, 15Ba of the first oscillating gear 15A and the second oscillating gear 15B come into contact with the internal tooth pins 20 held on the inner circumference of the outer cylindrical member 11 so as to mesh with each other.
In addition, reference numeral 28 in FIG. 1 denotes a crankshaft gear that is attached to the end of each crankshaft 14 and receives power from an electric motor.

In the reducer 10 of this embodiment, the number of teeth of each of the external teeth 15Aa, 15Ba of the first oscillating gear 15A and the second oscillating gear 15B is set to be slightly less than the number of the internal tooth pins 20 on the outer tube member 11 side. Therefore, while the first oscillating gear 15A and the second oscillating gear 15B make one oscillating rotation (one revolution), the first oscillating gear 15A and the second oscillating gear 15B receive a reaction force in the rotational direction from the internal tooth pins 20 on the outer tube member 11 side, and rotate by a predetermined pitch in the direction opposite to the oscillating rotation direction. As a result, the first and second carrier blocks 13A, 13B connected to the first oscillating gear 15A and the second oscillating gear 15B via the crankshaft 14 rotate in the same direction and at the same pitch together with the first and second oscillating gears 15A, 15B. As a result, the rotation of the crankshaft 14 is decelerated and output as the rotation of the first and second carrier blocks 13A, 13. In this embodiment, the outer cylinder member 11 is fixed to a mounting base portion (not shown), and the first carrier block 13A is connected to a rotation output member (not shown).
In the reducer 10 of this embodiment, the first and second oscillating gears 15A and 15B, the pin groove 17, the internal tooth pin 20, etc. form a reduction mechanism.

The bearings 12A and 12B interposed between the outer tube member 11 and the first and second carrier blocks 13A and 13B are roller bearings. Each of the bearings 12A and 12B has an outer race 31 fixed to the inner circumference of each end of the outer tube member 11 in the axial direction, an inner race 30 fixed to the outer circumference of each of the first and second carrier blocks 13A and 13B, a plurality of rollers 32 as rolling elements interposed between the outer race 31 and the inner race 30, and an annular cage 33 that holds the rollers 32 so that they can roll. In these bearings 12A and 12B, a straight line connecting the contact points of the inner race 30, the rollers 32, and the outer race 31 is inclined at a predetermined angle with respect to a plane perpendicular to the central axis of the bearings 12A and 12B. Each of the bearings 12A and 12B can support a radial load and an axial load in one direction.
The inner race 30 of the bearing 12A arranged on the first carrier block 13A side and the inner race 30 of the bearing 12B arranged on the second carrier block 13B side have different structures. Therefore, in order to distinguish between the two, the inner race arranged on the first carrier block 13A side is given the reference symbol 30A (30), and the inner race arranged on the second carrier block 13B side is given the reference symbol 30B (30).

FIG. 2 is an enlarged cross-sectional view of a portion II of the reducer 10 in FIG.
A bearing fixing surface 35 onto which the inner race 30A of the bearing 12A is press-fitted and a seal retaining surface 37 for retaining an annular seal member 36 are formed on the outer periphery of the base plate portion 13Aa of the first carrier block 13A. The seal member 36 seals the space between the inner periphery of the outer tubular member 11 and the first carrier block 13A at the axially outer position of the bearing 12A. In other words, the seal member 36 is a member that keeps the sealed space 40 surrounded by the outer tubular member 11 and the first and second carrier blocks 13A, 13B tightly sealed at the axially outer position of the bearing 12A.
The seal member 36 comprises an outer tube portion 36a whose outer peripheral surface contacts the seal support surface 41 on the inner circumference of the end portion of the outer tube member 11, a first lip 36b and a second lip 36c whose inner peripheral surface contacts the seal retaining surface 37, and a connecting wall 36d extending radially inward from the axially outer end of the outer tube portion 36a to connect the outer tube portion 36a to the first and second lips 36b, 36c.

The seal retaining surface 37 is disposed adjacent to the axially outer side of the bearing fixing surface 35. The seal retaining surface 37 and the bearing fixing surface 35 are peripheral surfaces of a concentric circular shape extending in the axial direction, and the outer diameter of the seal retaining surface 37 is set to be larger than the outer diameter of the bearing fixing surface 35. Between the bearing fixing surface 35 and the seal retaining surface 37, a step surface 38 is formed extending radially outward from the end of the bearing fixing surface 35. The inner race 30A pressed into the bearing fixing surface 35 is restricted from being displaced axially outward by abutting against the step surface 38. In addition, an end flange 39 extending radially outward is formed at the axially outer end of the seal retaining surface 37. The outer peripheral surface of the end flange 39 is formed to have approximately the same outer diameter as the outer diameter of the axially outer end of the outer tube member 11. The axially inner end face of the end flange 39 faces the axial end face of the outer tube member 11 with a small gap therebetween.

The seal support surface 41 and the bearing fixing surface 42 into which the outer race 31 of the bearing 12A is press-fitted are formed on the inner circumference of the end of the outer tube member 11 on the first carrier block 13A side. The seal support surface 41 and the bearing fixing surface 42 are concentric circular peripheral surfaces extending in the axial direction, and the seal support surface 41 is disposed axially outward of the bearing fixing surface 42. The inner diameter of the seal support surface 41 is set to be larger than the inner diameter of the bearing fixing surface 42. Between the bearing fixing surface 42 and the seal support surface 41, a step surface 43 is formed that extends radially outward from the axially outer end of the bearing fixing surface 42. In addition, a support surface 44 that extends radially inward is formed at the axially inner end of the bearing fixing surface 42. The outer race 31 press-fitted into the bearing fixing surface 42 is restricted from being displaced axially inward by abutting against the support surface 44.

The inner race 30A of the bearing 12A is formed of a metal block having an annular shape. The inner race 30A has an inner peripheral surface 46 that is press-fitted and fixed to the bearing fixing surface 35 of the first carrier block 13A, an outer surface 47 that abuts against the step surface 38 of the first carrier block 13A, and a rolling surface 48 against which the rollers 32, which are rolling elements, rotatably abut. The rolling surface 48 is formed in a tapered shape whose outer diameter decreases toward the axial inside (the right side in FIG. 2). A restricting wall 49 is formed at the radially outer position of the rolling surface 48 of the inner race 30A, which abuts against one end surface of the rollers 32 in the axial direction and restricts the axial displacement of the rollers 32. The restricting wall 49 is formed by the outer peripheral region of the inner race 30A that bulges outward in the radial direction from the rolling surface 48.

The restricting wall 49 has an annular overhang portion 50 that bulges axially inward from the rolling surface 48 at a radially outer position of the rolling surface 48. A restricting surface 50a is formed on the inner peripheral side of the overhang portion 50, against which the axial end face of the roller 32 can abut. The restricting surface 50a is formed in a tapered shape whose inner diameter expands toward the axially inner side (the right side in FIG. 2). In addition, a seal guide surface 50b whose outer diameter gradually expands toward the axially outer side is formed on the outer peripheral side of the overhang portion 50. An end outer peripheral surface 51 having a constant outer diameter is formed on the axially outer portion of the restricting wall 49 outside the overhang portion 50. The end outer peripheral surface 51 is formed to have the same outer diameter as the maximum outer diameter portion (the axially outer end) of the seal guide surface 50b and also has the same outer diameter as the seal holding surface 37 of the first carrier block 13A. Therefore, when the inner race 30A is assembled to the first carrier block 13A so that the outer surface 47 abuts against the stepped surface 38, the end outer peripheral surface 51 is continuous with the seal retaining surface 37 of the first carrier block 13A without any step.
In this embodiment, the seal retaining surface 37 and the end outer peripheral surface 51, which are formed to have the same outer diameter, constitute a protection mechanism that prevents damage to the inner peripheral surface (first lip 36b and second lip 36c) of the seal member 36. In addition, the seal guide surface 50b is disposed on the outer periphery of the end of the inner race 30A on the side adjacent to the seal retaining surface 37 in the axial direction, and the outer diameter gradually increases toward the side where the seal retaining surface 37 is disposed (the axially outer side).
The shape of the seal guide surface 50b is not limited to one in which the outer diameter expands linearly toward the axial outward, but may be one in which the outer diameter expands in a curved manner, one in which the way the outer diameter expands (inclination angle) changes halfway toward the axial outward, or one that includes a curved outer diameter change portion in part.

In the embodiment of the reducer 10, when the reducer 10 is assembled, the inner race 30A of the bearing 12A is press-fitted and fixed to the bearing fixing surface 35 of the first carrier block 13A in advance, and the outer race 31 of the bearing 12A and the rollers 32 held by the retainer 33 are attached to the outer cylinder member 11 side. In this state, the seal member 36 is attached to the inclined seal guide surface 50b of the inner race 30A, and the seal member 36 is pushed axially outward along the seal guide surface 50b. As a result, the seal member 36 moves onto the seal holding surface 37 of the first carrier block 13A via the end outer peripheral surface 51 of the inner race 30A. At this time, the inner surface of the seal member 36 (first lip 36b and second lip 36c) passes over the boundary between the end outer surface 51 of the inner race 30A and the seal retaining surface 37 of the first carrier block 13A, but because there is no step between the end outer surface 51 and the seal retaining surface 37, the inner surface of the seal member 36 is not damaged when passing over the boundary between the two.

After the seal member 36 is held on the seal holding surface 37 of the first carrier block 13A as described above, the outer tubular member 11 is assembled to the first carrier block 13A from the outside in the axial direction. At this time, the rollers 32 attached to the outer tubular member 11 together with the outer race 31 and the cage 33 rollably abut against the rolling surface 48 of the inner race 30A attached to the first carrier block 13A side. Thereafter, the second carrier block 13B is fastened and fixed to the support portions 13Ab of the first carrier block 13A by the bolts 16.
The bearing 12B interposed between the outer tube member 11 and the second carrier block 13B has a structure substantially similar to that of the bearing 12A on the first carrier block 13A side, except that the seal guide surface (50b) is not formed on the restricting wall (49) of the inner race 30B. As shown in FIG. 1, the inner race 30B is press-fitted and fixed to the bearing fixing surface 52 of the second carrier block 13B, and its axial displacement is restricted by the end flange 53 of the second carrier block 13B. A preload is applied to the bearings 12A and 12B by fastening the first and second carrier blocks 13A and 13B with the bolts 16. A spacer 54 for adjusting the preload is interposed between the inner race 30B and the end flange 53 of the second carrier block 13B.

As described above, the inner race 30A of the bearing 12A used in the reducer 10 (rotating device) of this embodiment has a seal guide surface 50b formed on the outer periphery of the end of the inner race 30A. The outer diameter of the seal guide surface 50b gradually expands toward the seal retaining surface 37. Therefore, when the seal member 36 is attached to the seal retaining surface 37, the seal member 36 can be smoothly moved onto the seal retaining surface 37 through the inclined seal guide surface 50b.

Furthermore, since the seal guide surface 50b that guides the installation of the seal member 36 is formed on the outer periphery of the end of the inner race 30A, the axial length of the first carrier block 13A (inner member) of the reducer 10 (rotating device) can be shortened compared to a case in which a similar seal guide surface is provided at a position adjacent to the seal retaining surface 37 on the first carrier block 13A (inner member). Therefore, in a reducer 10 (rotating device) that employs the inner race 30A of this embodiment, the entire reducer 10 can be made smaller.

In addition, in the reducer 10 (rotating device) of this embodiment, the seal guide surface 50b is formed on the regulating wall 49 of the inner race 30A, which regulates the displacement of the rollers 32 (rolling elements) of the bearing 12A. As a result, a portion of the regulating wall 49 of the inner race 30A also serves as the seal guide surface 50b, making it possible to shorten the axial length of the inner race 30A compared to when the regulating wall and the seal guide surface are provided separately.

In addition, in the reducer 10 (rotating device) of this embodiment, the seal retaining surface 37 of the first carrier block 13A (inner member) and the end outer peripheral surface 51 of the inner race 30A are formed by circular outer peripheral surfaces of the same outer diameter without any steps (a protection mechanism is provided between the seal retaining surface 37 and the seal guide surface 50b). Therefore, when the seal member 36 is attached to the seal guide surface 50b of the inner race 30A during assembly of the reducer 10, and in this state, when the seal member 36 is moved in the direction of the seal retaining surface 37 on the first carrier block 13A side, the inner peripheral surface of the seal member 36 (the first lip 36b and the second lip 36c) can be prevented from getting caught on the boundary between the end outer peripheral surface 51 and the seal retaining surface 37.

(First Modification)
FIG. 3 is an enlarged cross-sectional view similar to FIG. 2 of the reducer 10 of the first modified example.
The reducer 10 of this modified example is slightly different from the basic embodiment in the configuration of the protection mechanism that prevents damage to the inner peripheral surface of the seal member 36. In the basic embodiment, the seal retaining surface 37 of the first carrier block 13A (inner member) and the end outer peripheral surface 51 of the inner race 30A are formed into circular shapes with the same outer diameter and without any steps. In contrast, in this modified example, the seal retaining surface 37 and the end outer peripheral surface 51 are formed into circular shapes with the same outer diameter, and a smooth curved surface 58 is formed in the outer peripheral corner portion where the two butt together.

Therefore, in the protective mechanism of this modified example, even if a small gap occurs between the seal retaining surface 37 and the end outer peripheral surface 51, it is possible to prevent the inner peripheral surface of the seal member 36 from getting caught on the boundary between the seal retaining surface 37 and the end outer peripheral surface 51 when the seal member 36 is attached.

(Second Modification)
FIG. 4 is an enlarged cross-sectional view similar to FIG. 2 of the reducer 10 according to the second modified example.
The reducer 10 of this modification differs from the basic form and the first modification in the configuration of a protection mechanism that prevents damage to the inner peripheral surface of the seal member 36. In the basic form and the first modification, the seal retaining surface 37 of the first carrier block 13A (inner member) and the end outer peripheral surface 51 of the inner race 30A are formed to have the same outer diameter. In contrast, in this modification, the outer diameter of the end outer peripheral surface 51 of the inner race 30A is formed smaller than the outer diameter of the seal retaining surface 37 of the first carrier block 13A, and a chamfered portion 59 (tapered portion) is provided at the outer peripheral corner portion of the seal retaining surface 37 on the inner race 30A side.

Therefore, in the protective mechanism of this modification, when the seal member 36 is moved from the end outer peripheral surface 51 of the inner race 30A onto the seal retaining surface 37 during installation, the seal member 36 can be moved smoothly onto the seal retaining surface 37 through the chamfered portion 59. Therefore, when the protective mechanism of this modification is adopted, it is possible to more reliably prevent the inner peripheral surface of the seal member 36 from getting caught on the boundary between the seal retaining surface 37 and the end outer peripheral surface 51.

Second Embodiment
FIG. 5 is a cross-sectional view similar to FIG. 2 of a reducer (rotating device) according to a second embodiment.
The reducer 110 (rotating device) of this embodiment differs from that of the first embodiment in the structure of a first carrier block 113A and an inner race 130A of a bearing 112A fixed to the first carrier block 113A. The first carrier block 113A does not have a seal retaining surface (37) as in the first embodiment, and the end outer peripheral surface of the inner race 130A serves as a seal retaining surface 151. In addition, the bearing fixing surface 135 of the first carrier block 113A to which the inner race 130A is press-fitted and fixed extends to the root portion of the end flange 39, and an annular seal receiving groove 62 is formed in an end surface 39a on the root side of the end flange 39 with which the outer surface 47 of the inner race 130A abuts.

A first seal member 136 having the same structure as the seal member (36) used in the first embodiment is interposed between the seal retaining surface 151 of the inner race 130A fixed to the first carrier block 113A and the seal support surface 41 on the inner circumference of the outer tube member 11. A ring-shaped second seal member 63 that seals the gap between the end flange 39 and the outer surface 47 of the inner race 130A is accommodated in the seal accommodation groove 62 of the end flange 39. The second seal member 63 may be, for example, a ring-shaped elastic member having a substantially circular cross section.

In this embodiment, the first seal member 136 and the second seal member 63 constitute a sealing mechanism that keeps the sealed space 40 between the first carrier block 113A (inner member) and the outer tube member 11 tight. Note that in this embodiment, the first seal member 136 and the second seal member 63 constitute the sealing mechanism, but if the gap between the first carrier block 113A and the inner race 130A can be sealed without using the second seal member 63, the sealing mechanism can be formed only by the first seal member 136.

When assembling the reducer 110, the inner race 130A of the bearing 112A is press-fitted and fixed in advance to the bearing fixing surface 135 of the first carrier block 113A. At this time, the second seal member 63 is accommodated in the seal accommodating groove 62 in the end face 39a of the first carrier block 113A, and the gap between the end face 39a of the first carrier block 113A and the outer surface 47 of the inner race 130A is sealed by the second seal member 63. Meanwhile, the outer race 31 of the bearing 112A and the rollers 32 held in the cage 33 are attached in advance to the outer tubular member 11 side.
In this state, the first seal member 136 is attached to the inclined seal guide surface 50b of the inner race 130A, and the first seal member 136 is pushed axially outward along the seal guide surface 50b, causing the first seal member 136 to move onto the seal retaining surface 151 along the seal guide surface 50b of the inner race 130A.

Then, the outer tube member 11 is assembled to the first carrier block 113A from the outside in the axial direction, and the second carrier block is bolted to the support portion of the first carrier block 113A. As a result, the rollers 32 of the bearing 112A rollably contact the rolling surface 48 of the inner race 130A attached to the first carrier block 113A side, and the sealed space 40 inside the outer tube member 11 is sealed by the first seal member 136 and the second seal member 63.

As described above, the reducer 110 (rotating device) of this embodiment is provided with a seal retaining surface 151 where the inner peripheral surface (first lip 36b and second lip 36c) of the first seal member 136 abuts on the inner race 130A that is press-fitted and fixed to the first carrier block 113A, and the seal retaining surface 151 (outer peripheral surface) of the inner race 130A and the outer tube member 11 are sealed by the first seal member 136. Therefore, the reducer 110 of this embodiment can shorten the axial length of the first carrier block 113A (inner member) compared to the case where a seal member is interposed between the outer peripheral surface of the first carrier block 113A (inner member) and the outer tube member 11. Therefore, when the reducer 110 of this embodiment is adopted, the reducer 110 can be made smaller.

In addition, in the reducer 110 (rotating device) of this embodiment, a second seal member 63 is interposed between the end face 39a of the end flange 39 of the first carrier block 113A (inner member) and the outer surface 47 of the inner race 130A to seal the gap between them. Therefore, when the reducer 110 (rotating device) of this embodiment is used, it is possible to prevent foreign matter from entering the sealed space 40 through the gap between the inner race 130A of the bearing 112A and the first carrier block 113A (inner member).

Furthermore, in the reducer 110 (rotating device) of this embodiment, the outer peripheral surface of the inner race 130A of the bearing 112A is formed with a seal retaining surface 151 that retains the first seal member 136, and a seal guide surface 50b whose outer diameter gradually expands toward the seal retaining surface 151. Therefore, when the first seal member 136 is attached to the seal retaining surface 151 of the inner race 130A during assembly of the reducer 110, the first seal member 136 is first attached to the seal guide surface 50b, and from that state, the first seal member 136 can be moved axially outward along the inclined shape of the seal guide surface 50b. At this time, the first seal member 136 moves onto the seal retaining surface 151 while the inner peripheral surface is gradually expanded by the seal guide surface 50b. Therefore, when the reducer 110 (rotating device) of this embodiment is used, the first seal member 136 can be easily attached to the seal retaining surface 151 of the inner race 130A when assembling the reducer 110.

In addition, the reducer 110 (rotating device) of this embodiment is provided with a restricting wall 49 that restricts the displacement of the roller 32, which is a rolling element, at a position adjacent to the seal retaining surface 151 of the inner race 130A, and a seal guide surface 50b, whose outer diameter gradually expands toward the axially outward direction, is formed on the outer periphery of the restricting wall 49. Therefore, in the reducer 110 of this embodiment, a part of the restricting wall 49 of the inner race 130A also serves as the seal guide surface 50b. Therefore, the axial length of the inner race 130A can be made shorter than when the restricting wall and the seal guide surface are separately provided on the inner race 130A. Therefore, when the reducer 110 of this embodiment is adopted, the reducer 110 can be further miniaturized.

The present invention is not limited to the above embodiment, and various design changes are possible without departing from the gist of the invention. For example, in the above embodiment, the inner race of the bearing according to the present invention is used in a reducer, but the rotating device in which it is used is not limited to a reducer, and may be a rotating device that does not have a reduction mechanism.

10, 110...reduction gear (rotating device), 11...outer cylinder member, 12A, 112A...bearing, 13A, 113A...first carrier block, 14...crankshaft (input member), 15A...first oscillating gear (reduction mechanism), 15B...second oscillating gear (reduction mechanism), 17...pin groove (reduction mechanism), 20...inner pin (reduction mechanism), 30A, 130A...inner race, 32...roller (rolling element), 36...seal member, 37...seal retaining surface, 40...sealed space, 47..., 49...regulating wall, 50b...seal guide surface, 63...second seal member, 136...first seal member, 151...seal retaining surface.

Claims (13)

A bearing having a seal member interposed between an inner member and an outer cylindrical member which are rotatable relative to each other, the inner race being disposed adjacent to a seal retaining surface on the inner member which retains the seal member,
An inner race of a bearing having a seal guide surface that guides the seal member on the seal retaining surface. 2. The inner race of a bearing according to claim 1, wherein the seal guide surface has an outer diameter that gradually increases from an outer periphery of an end portion adjacent to the seal retaining surface toward a side where the seal retaining surface is disposed. 3. The inner race of a bearing as described in claim 2, wherein the seal guide surface is formed as a regulating wall that regulates displacement of the rolling elements of the bearing at an end portion adjacent to the seal retaining surface in the axial direction of the relative rotation axis of the inner member and the outer cylindrical member. an inner member having a seal retaining surface;
an outer cylinder member arranged on an outer circumferential side of the inner member so as to be relatively rotatable;
a seal member interposed between the inner member and the outer casing member;
a bearing interposed between the inner member and the outer cylindrical member alongside the seal member along an axial direction which is a direction in which a relative rotation axis of the inner member and the outer cylindrical member extends;
Equipped with
the bearing includes an inner race disposed adjacent to the seal retaining surface on the inner member on the sealed space side in the axial direction,
The inner race is provided with a seal guide surface that guides the seal member to the seal holding surface . The rotating device according to claim 4 , wherein the seal guide surface has an outer diameter that gradually increases from an outer periphery of an end portion adjacent to the seal retaining surface in the axial direction toward a side where the seal retaining surface is disposed. The bearing further comprises a rolling element,
the inner race includes a restricting wall that restricts displacement of the rolling elements at an end portion adjacent to the seal retaining surface in the axial direction,
The rotating device according to claim 5 , wherein the seal guide surface is formed on the restriction wall. 7. The rotating device according to claim 5 , wherein a protection mechanism for preventing damage to an inner peripheral surface of the seal member is provided between the seal holding surface and the seal guide surface. an inner member having a seal retaining surface;
an outer cylinder member arranged on an outer circumferential side of the inner member so as to be relatively rotatable;
an input member to which a rotational driving force is input;
a reduction mechanism that reduces the speed of a rotational driving force input to the input member and transmits the rotational driving force to the inner member or the outer tube member;
a seal member interposed between the inner member and the outer casing member;
a bearing interposed between the inner member and the outer cylindrical member alongside the seal member along an axial direction which is a direction in which a relative rotation axis of the inner member and the outer cylindrical member extends;
Equipped with
the bearing includes an inner race disposed adjacent to the seal retaining surface on the inner member on the sealed space side in the axial direction,
The inner race has a seal guide surface that guides the seal member to the seal retaining surface . The reducer according to claim 8 , wherein the seal guide surface has an outer diameter that gradually increases from an outer periphery of an end portion adjacent to the seal retaining surface in the axial direction toward a side where the seal retaining surface is located. An inner member;
an outer cylinder member arranged on an outer circumferential side of the inner member so as to be relatively rotatable;
a sealing mechanism for tightly sealing a space between the inner member and the outer cylinder member;
a bearing interposed between the inner member and the outer cylindrical member;
Equipped with
The bearing includes an inner race,
The sealing mechanism includes:
a first seal member that seals a gap between an outer peripheral surface of the inner race and the outer tubular member;
a second seal member that seals between the inner race and the inner member;
A rotating device comprising: The inner race is
a seal retaining surface that retains the first seal member;
a seal guide surface whose outer diameter gradually increases toward the seal retaining surface in an axial direction along which a relative rotation axis of the inner member and the outer cylindrical member extends;
The rotating device according to claim 10 , further comprising: The bearing further comprises a rolling element,
the inner race includes a restriction wall that restricts displacement of the rolling elements at a position adjacent to the seal retaining surface in the axial direction,
The rotating device according to claim 11 , wherein the seal guide surface is formed on the restriction wall. an inner member having a seal retaining surface;
an outer cylinder member arranged on an outer circumferential side of the inner member so as to be relatively rotatable;
an input member to which a rotational driving force is input;
a reduction mechanism that reduces the speed of a rotational driving force input to the input member and transmits the rotational driving force to the inner member or the outer tube member;
a sealing mechanism for tightly sealing a space between the inner member and the outer cylinder member;
a bearing interposed between the inner member and the outer cylindrical member;
Equipped with
The bearing includes an inner race,
The sealing mechanism includes:
a first seal member that seals a gap between an outer peripheral surface of the inner race and the outer tubular member;
a second seal member that seals between the inner race and the inner member;
A reducer comprising:

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