CN104285081A

CN104285081A - Gearwheel drive

Info

Publication number: CN104285081A
Application number: CN201380020927.5A
Authority: CN
Inventors: 广濑真哉
Original assignee: Nabtesco Corp
Current assignee: Nabtesco Corp
Priority date: 2012-04-20
Filing date: 2013-04-04
Publication date: 2015-01-14
Anticipated expiration: 2033-04-04
Also published as: KR20140146205A; DE112013002093T5; TWI600849B; JP2013224700A; WO2013157397A3; WO2013157397A2; KR101656165B1; DE112013002093B4; JP5417481B2; TW201402969A

Abstract

A carrier is supported on a casing via a tapered roller bearing. The tapered roller bearing comprises an inner race, an outer race, tapered rollers and a retainer. The inner race is mounted to a carrier. The outer race is mounted to a casing. The tapered rollers are positioned between the inner race and the outer race. The outer peripheral surface of the inner race and the inner peripheral surface of the outer race are not provided with ribs that restrict the tapered rollers from moving in a direction away from the central axis of the bearings. The end where the diameter of the retainer is the greatest comes into contact with the carrier in the central axis direction of the bearing, and comes into contact with the casing in a direction perpendicular to the central axis of the bearing.

Description

Gear drive

Technical field

Japan's patent that the application filed an application based on April 20th, 2012 goes out hope 2012-097080 CLAIM OF PRIORITY.Be incorporated in this specification by referring to the full content that this is gone out to be willing to.This specification relates to gear drive.Particularly relate to the gear drive being provided with tapered roller bearing between support and housing.

Background technique

Be known in housing, contain gear train, support are supported on housing gear drive by bearing.The gear drive being configured with tapered roller bearing between housing and support is disclosed in Japanese Unexamined Patent Publication 2008-240852 publication.In the following description, Japanese Unexamined Patent Publication 2008-240852 publication is called patent documentation 1.When tapered roller bearing, moving axially along it to limit tapered roller, needing the end face of the side, large footpath to tapered roller to retrain.In the technology of patent documentation 1, be formed with rib at the outer circumferential face of inner ring, and make the end contact of the side, large footpath of this rib and tapered roller.In addition, in this manual, in order to simplify, below sometimes by " tapered roller " referred to as " roller ".

Summary of the invention

If make rib and the roller-contact of the outer circumferential face being formed at inner ring as patent documentation 1, then there is the situation of the end wear of roller.Thus, there is the deterioration promoting tapered roller bearing, the situation of the durability reduction of gear drive.This specification is provided for the technology of the deterioration suppressing the tapered roller bearing be configured between housing and support.In addition, there is type that to carry out using support as output shaft rotating and carry out the type that rotates using housing as output shaft in gear drive.Below, in order to be described simply, illustrate that housing is static and carries out the gear drive of the type rotated using support as output shaft.

Technology disclosed in this specification relates to support is supported on housing gear drive by tapered roller bearing.In this gear drive, tapered roller bearing comprises the inner ring being installed on support, the outer ring being installed on housing, be configured in the multiple tapered roller between inner ring and outer ring and be configured between inner ring and outer ring and for the retainer of the ring-type that maintains the interval between adjacent tapered roller.In this gear drive, the minor diameter part of tapered roller is positioned at the position leaning on bearing centre axle side than the large-diameter portion of tapered roller.More precisely, the center than the large-diameter portion of tapered roller of being centrally located at of the minor diameter part of tapered roller is by the position of bearing centre axle side.The outer circumferential face of inner ring and the inner peripheral surface of outer ring are not provided with for limiting tapered roller along the rib of direction movement leaving bearing central axis.More specifically, the rib abutted with the large-diameter portion of tapered roller is not located at any one in inner ring and outer ring.In addition, retainer is formed by the material that rigidity is lower than the rigidity of support and housing.Further, support surface of contact and body contact face is provided with in the end that the diameter of retainer is larger.The direction of support surface of contact axle line within the bearing contacts with support.Body contact face on the direction orthogonal with bearing central axis with body contact.

Adopt above-mentioned gear drive, retainer contacts with both supports with housing, thus the movement (leaving the direction of bearing central axis) laterally of tapered roller (roller) is restricted.The end face of roller does not contact with other component (rib), therefore, it is possible to suppress the wearing and tearing of the end face of roller.Its result, can suppress the deterioration of tapered roller bearing.In addition, retainer does not need to contact with both supports with housing all the time.In the process that gear drive is static, retainer (body contact face and support surface of contact) also can leave housing and support.In the driving process of gear drive, when making the masterpiece of roller movement laterally for roller, as long as retainer contacts with both supports with housing.In addition, above-mentioned gear drive except have suppress the wearing and tearing of end face of roller such advantage except, also there is various advantage.What below describe in these advantages is several.

As the 1st advantage, rotating speed when can make the rotating speed of retainer any one does not contact with housing and support close to retainer.Such as, when retainer only contacts with support, between retainer and support, produce friction, therefore, the rotating speed of retainer is slack-off, and the travelling speed of roller is slack-off.The slip of roller becomes large, and therefore, the side face of roller becomes easy wearing and tearing.As long as retainer contacts with both housings with support, just can reduce the slip of roller, therefore, it is possible to suppress the wearing and tearing of the side face of roller.

As the 2nd advantage, retainer contacts with both housings with support, and therefore, in the driving process of gear drive, foreign matter is mixed into the inside of gear drive situation from the outside of gear drive is suppressed.The situation that foreign matter is mixed into the inside of tapered roller bearing is suppressed, and therefore, the situation of the wearing and tearing progress of roller is suppressed.

As the 3rd advantage, retainer is formed by the material that rigidity is lower than the rigidity of support and housing, and therefore, retainer contacts with housing equably with support in the circumferential.As an example of the material of retainer, resin can be listed.

As the 4th advantage, the processing of inner ring and/or outer ring easily can be carried out.If be provided with rib at the outer circumferential face of inner ring and/or the inner peripheral surface of outer ring, then the surface to rib (with the surface of contact of roller-contact) is needed to grind.Above-mentioned gear drive does not exist for limiting roller to the rib moved axially, therefore, it is possible to reduce the processing cost of inner ring and/or outer ring.

As the 5th advantage, the axial length of roller can be made to extend the length corresponding to not being formed with above-mentioned rib.Thereby, it is possible to improve the capacity (load) of tapered roller bearing.

Accompanying drawing explanation

Fig. 1 represents the sectional view of the gear drive of the 1st embodiment.

Fig. 2 represents the amplification view of the scope II of Fig. 1.

Fig. 3 represents the skeleton diagram of the outward appearance of retainer.

Fig. 4 represents that the figure (plan view) of retainer is observed in the direction from bearing central axis.

Fig. 5 represents the figure (plan view) observing retainer from the direction orthogonal with bearing central axis.

Fig. 6 represents the figure of the action for illustration of roller.

Fig. 7 represents the plan view of retainer used in the gear drive of the 2nd embodiment.

Fig. 8 represents the plan view of retainer used in the gear drive of the 2nd embodiment.

Fig. 9 represents the plan view of retainer used in the gear drive of the 3rd embodiment.

Figure 10 represents the plan view of retainer used in the gear drive of the 3rd embodiment.

Figure 11 represents the sectional view of the gear drive of the 4th embodiment.

Embodiment

Below in an example, be described employing the gear drive being formed with the retainer of groove on both support surface of contact and body contact face.But, disclosed in this manual technology also can be applied in the one that employs in support surface of contact and body contact face and be formed with the gear drive of the retainer of groove and employ the gear drive of the retainer not all being formed with groove on support surface of contact and body contact face.

If at least one in support surface of contact and body contact face is formed with groove, then can obtain following advantage.When retainer contacts with support with housing, the path externally to inside from tapered roller bearing of oiling agent can be guaranteed.Even if i.e. retainer and support and body contact, oiling agent also can move via the inside of above-mentioned groove to tapered roller bearing.Its result, can suppress the progress of roller wear further.In addition, the serviceability on the technology at least one in support surface of contact and body contact face being formed with groove possesses skills individually.

Embodiment

In an embodiment, external gear wheel engages with internal gear while the gear drive carrying out the type of eccentric rotary is described.Wish to notice, the technology disclosed in this specification also can be applied to the gear drive of other types, and such as internal gear engages while carry out the gear drive of the type of eccentric rotary with external gear.

(the 1st embodiment)

Fig. 1 represents the sectional view of gear drive 100.Gear drive 100 is external gears 22 while engage while carry out the speed reducer of the type of eccentric rotary with internal gear 24.In gear drive 100, the number of teeth official post support 10 between the number of teeth of the number of teeth of external gear 22 and internal gear 24 is utilized to rotate.The torque that gear drive 100 utilizes above-mentioned number of teeth official post to be delivered to bent axle 16 increases (rotation is slowed down) and exports from support 10.In addition, support 10 is equivalent to the output shaft of gear drive 100.Axis 30 is equivalent to the spin axis of support 10.Axis 30 is also equivalent to the axis of gear drive 100.Further, axis 30 is also equivalent to the bearing central axis of tapered roller bearing 2 described later.

Gear drive 100 has internal gear 24, support 10, external gear 22 and bent axle 16.Internal gear 24 is made up of housing 4 and multiple interior alligator 5.Housing 4 has minor diameter part 4a and large-diameter portion 4b.Minor diameter part 4a extends from the two ends of large-diameter portion 4b along axis 30.Internal gear 24 is formed at the large-diameter portion 4b of housing 4.Minor diameter part 4a is configured with a pair tapered roller bearing 2.A pair tapered roller bearing 2 limit bracket 10 axially and move radially.Tapered roller bearing 2 can be called the main bearing of gear drive 100.The details of tapered roller bearing 2 is discussed subsequently.

Support 10 is supported on housing 4 by a pair tapered roller bearing 2.Support 10 is made up of the 1st plate 10a and the 2nd plate 10c.Be extended with columnar part 10b from the 1st plate 10a towards the 2nd plate 10c, columnar part 10b and the 2nd plate 10c is fixed.The 1st flange 10d that (direction orthogonal with axis 30) extends is formed radially in the end of the 1st plate 10a.In addition, the 2nd flange 10e radially extended is provided with in the end of the 2nd plate 10c.A pair tapered roller bearing 2 is configured at the 1st flange 10d and the 2nd flange 10e.1st flange 10d and the 2nd flange 10e also can be called the protuberance of the 1st plate 10a and the protuberance of the 2nd plate 10c.In addition, support 10 and housing 4 are metal.

Bent axle 16 is supported on support 10 by a pair tapered roller bearing 19.A pair tapered roller bearing 19 limits bent axle 16 axially and move radially.Bent axle 16 extends abreast in the position biased with axis 30 and axis 30.Bent axle 16 has input gear 28 and eccentric body 18.Input gear 28 is fixed in bent axle 16 in the outside of a pair tapered roller bearing 19.Eccentric body 18 is between a pair tapered roller bearing 19.External gear 22 is formed through hole 14.Eccentric body 18 is sticked in through hole 14 by roller bearing 20.External gear 22 is supported on support 10 by bent axle 16.

When the transmission of torque of motor (omitting diagram) is to input gear 28, bent axle 16 rotates.Along with the rotation of bent axle 16, eccentric body 18 carries out eccentric rotary.The axis (omitting diagram) of eccentric body 18 flexing axle 16 carries out eccentric rotary.Along with the eccentric rotary of eccentric body 18, external gear 22 engages while carry out eccentric rotary with internal gear 24.External gear 22 is around axis 30 eccentric rotary.The number of teeth of external gear 22 is different from the number of teeth (quantity of interior alligator 5) of internal gear 24.Therefore, when external gear 22 eccentric rotary, and the poor support 10 that correspondingly carry external gear 22 of the number of teeth between external gear 22 and internal gear 24 rotates relative to internal gear 24 (housing 4).

Tapered roller bearing 2 is explained with reference to Fig. 2.Tapered roller bearing 2 has inner ring 46, outer ring 40, roller 42 (tapered roller) and retainer 44.The inner ring 46 of ring-type has the outer circumferential face 46b of taper.Namely, the outer circumferential face 46b of inner ring 46 tilts relative to axis 30 (with reference to Fig. 1).Inner ring 46 is pressed into the outside of the 2nd plate 10c of support 10.The inner peripheral surface 46a of inner ring 46 contacts with the outer circumferential face of the 2nd plate 10c.The end face 46c in axis 30 direction of inner ring 46 contacts with the 2nd flange 10e.Inner ring 46 is installed on support 10, relative to support 10 no matter along axis 30 direction or be all radially motionless.Alternatively inner ring 46 is integrated with support 10.

The outer ring 40 of ring-type has the inner peripheral surface 40b of taper.The inner peripheral surface 40b of the outer ring 40 and outer circumferential face 46b of inner ring 46 is face-to-face.Outer ring 40 is pressed into the inner side of the minor diameter part 4a of housing 4.The outer circumferential face 40a of outer ring 40 contacts with the inner peripheral surface of housing 4 (minor diameter part 4a).The end face 40c in axis 30 direction of outer ring 40 contacts with the large-diameter portion 4b of housing 4.Outer ring 40 is installed on housing 4, relative to housing 4 no matter along axis 30 direction or be all radially motionless.Alternatively outer ring 40 is integrated with housing 4.

Gap (for configuring the gap of roller 42) between the inner peripheral surface 40b of the outer ring 40 and outer circumferential face 46b of inner ring 46 is gone along with (leaving the direction of bearing central axis 30) toward the outer side and broadens gradually.In other words, inner peripheral surface 40b is larger relative to the tilt angle of axis 30 than outer circumferential face 46b relative to the tilt angle of axis 30.

Roller (tapered roller) 42 is configured between inner ring 46 and outer ring 40.The external diameter of roller 42 goes along with (leaving the direction of bearing central axis 30) toward the outer side and becomes large gradually.The external diameter of the 1st end face 42a of the large-diameter portion side of roller 42 is larger than the external diameter of the 2nd end face 42b of the minor diameter part side of roller 42.The running shaft of roller 42 tilts relative to axis 30 (with reference to Fig. 1).The center than large-diameter portion of being centrally located at of the minor diameter part of roller 42 is by the position near bearing central axis 30.Multiple roller 42 is arranged at equal intervals between inner ring 46 and outer ring 40.Namely, multiple roller 42 is arranged at equal intervals around axis 30.The axial length of rotation of roller 42 is shorter than the length of the outer circumferential face 46b of inner ring 46 and the inner peripheral surface 40b of outer ring 40.The outer circumferential face of roller 42 contacts with the inner peripheral surface 40b of outer ring 40 with the outer circumferential face 46b of inner ring 46.1st end face 42a does not contact with outer ring 40 with inner ring 46 with the 2nd end face 42b.

Retainer 44 is configured between inner ring 46 and outer ring 40.The material of retainer 44 is resins.As shown in Figure 3, retainer 44 in the form of a ring, has the 1st larger end 44a of diameter, the 2nd end 44b that diameter is less than the diameter of the 1st end 44a.Retainer 44 has the multiple recess 44c circumferentially arranged.Roller 42 is inserted with in recess 44c.Retainer 44 is for maintaining the interval between adjacent roller 42.In addition, roller 42 is inserted in recess 44c, and therefore, the 1st end face 42a and the 2nd end face 42b of roller 42 are retrained by retainer 44.Namely, retainer 44 pairs of rollers 42 to rotation axial movement limit.In addition, Fig. 3 is the figure of the global shape for retainer 44 is described simply, instead of for the figure of the shape that represents retainer 44 exactly.The detailed shape of retainer 44 is discussed subsequently.

As shown in Figure 2, the body contact face 44d contacted with housing 4, the support surface of contact 44e contacted with support 10 is formed with at the 1st end 44a of retainer 44.Body contact face 44d is formed in (also with reference to Fig. 1) on the direction orthogonal with axis 30.Body contact face 44d is the outer circumferential face of retainer 44, contacts with the inner peripheral surface of housing 4 (minor diameter part 4a).The surface of contact (local of body contact face 44d) that retainer 44 contacts with housing 4 is in concentric cylindric with axis 30.Support surface of contact 44e is formed on axis 30 direction.Support surface of contact 44e is the end face in bearing central axis (axis 30) direction of retainer 44.Support surface of contact 44e within the bearing axle line 30 direction contacts with the 2nd flange 10e of support 10 (the 2nd plate 10c).The surface of contact (local of support surface of contact 44e) that retainer 44 contacts with support 10 is orthogonal with axis 30.

At this, with reference to Fig. 4, Fig. 5, explain retainer 44.Body contact face 44d is formed in bearing central axis 30 in concentric circumferentially (outer circumferential face of retainer 44).Body contact face 44d is formed with multiple circumferential groove 44f.Circumferential groove 44f extends along bearing central axis 30, is equally spaced formed around bearing central axis 30.Also can be expressed as body contact face 44d to be formed between adjacent circumferential groove 44f.Even if body contact face 44d contacts with housing 4, circumferential groove 44f also can not contact with housing 4.

Support surface of contact 44e is formed in the plane orthogonal with bearing central axis 30.Support surface of contact 44e is formed with multiple end face groove 44g.End face groove 44g extends along the radial direction of retainer 44, is disposed at equal intervals around bearing central axis 30.Also can be expressed as support surface of contact 44e to be formed between adjacent end face groove 44g.The inner side and outer side of retainer 44 is communicated with to get up by end face groove 44g.Even if support surface of contact 44e contacts with support 10, end face groove 44g does not also contact with support 10.

Circumferential groove 44f and end face groove 44g alternately configures along the circumference of retainer 44.In other words, in the circumference of retainer 44, circumferential groove 44f is formed between adjacent end face groove 44g, and end face groove 44g is formed between adjacent circumferential groove 44f.The quantity of circumferential groove 44f is equal with the quantity of end face groove 44g.In addition, the area of body contact face 44d and the area of support surface of contact 44e roughly equal.The area W1 of the surface of contact that the retainer 44 namely, shown in Fig. 2 contacts with housing 4 is substantially equal to the area W2 of the surface of contact that retainer 44 contacts with support 10.

In addition, in fig. 2, the state that body contact face 44d contacts with support 10 with housing 4 respectively with support surface of contact 44e is represented.Namely the state, representing that the 1st end 44a of retainer 44 upper to contact with housing 4 in the direction (radial direction of retainer 44) orthogonal with bearing central axis 30, within the bearing axle line 30 direction contacts with support 10.When non-actuation gear transmission device 100, body contact face 44d also can not contact with support 10 with housing 4 with support surface of contact 44e.Importantly, when applying to make the power of its movement laterally to roller 42, body contact face 44d contacts with support 10 with housing 4 respectively with support surface of contact 44e.

The advantage of gear drive 100 is described.In the driving process of gear drive 100, have to roller 42 effect the power making roller 42 movement of (leaving the direction of bearing central axis 30) laterally.As mentioned above, when roller 42 is for moving laterally, the 1st end 44a of retainer 44 contacts with support 10 with housing 4.Therefore, roller 42 to rotation axial movement be restricted.

In addition, as mentioned above, the outer circumferential face 46b of inner ring 46 is tapers of straight line, does not have rib.Similarly the inner peripheral surface 40b of outer ring 40 is also the taper of straight line, does not also have rib.In other words, the outer circumferential face 46b of inner ring 46 and the inner peripheral surface 40b of outer ring 40 are not provided with the rib for limiting roller 42 movement laterally.More specifically, outer circumferential face 46b and inner peripheral surface 40b are not provided with the protuberance (rib) that the 1st end 44a of covering roller 42 is such.

Above-mentioned feature also can be stated as follows.The outer circumferential face 46b of inner ring 46 has the 1st region 46d and the 2nd region 46e that do not contact with the outer circumferential face of roller 42.The external diameter in the 1st region 46d of inner ring 46 is larger than the external diameter in the 2nd region 46e of inner ring 46.Namely, the thickness in the 2nd region 46e of the Thickness Ratio inner ring 46 in the 1st region 46d of inner ring 46 is large.In addition, the inner peripheral surface 40b of outer ring 40 has the 3rd region 40d and the 4th region 40e that do not contact with the outer circumferential face of roller 42.The external diameter in the 3rd region 40d of outer ring 40 is larger than the external diameter in the 4th region 40e of outer ring.Namely, the thickness in the 4th region 40e of the Thickness Ratio outer ring 40 in the 3rd region 40d of outer ring 40 is little.Gap between 1st region 46d and the 3rd region 40d is more than or equal to the external diameter of the 1st end 44a of roller 42.

By having above-mentioned feature, even if having to roller 42 effect the power making roller 42 movement laterally, the 1st end face 42a of roller 42 also can not contact with outer ring 40 with inner ring 46.Its result, the wearing and tearing of roller 42 are suppressed, can suppress the deterioration of tapered roller bearing 2.

In addition, in tapered roller bearing 2, in the 2nd region 46e of inner ring 46 and the 4th region 40e of outer ring 40, rib is not provided with yet.But, also rib can be provided with in the 2nd region 46e and/or the 4th region 40e.If be provided with rib in the 2nd region 46e and/or the 4th region 40e, then can supporting roller 42 when assembling tapered roller bearing 2.Can easily Assembling gear transmission device 100.

In addition, even if be provided with rib in the 2nd region 46e and/or the 4th region 40e, the 2nd end face 42b of roller 42 also weares and teares hardly.As mentioned above, the gap between the outer circumferential face 46b of the inner ring 46 and inner peripheral surface 40b of outer ring 40 is gone along with (leaving the direction of bearing central axis 30) toward the outer side and broadens gradually.In addition, the external diameter of roller 42 becomes large along with going toward the outer side gradually.Therefore, the movement of roller 42 (bearing central axis 30 side) is to the inside restricted.Even if be namely provided with rib in the 2nd region 46e and/or the 4th region 40e, between this rib and the 2nd end face 42b, also can not produce larger friction.

Other advantages of gear drive 100 are described.As mentioned above, on tapered roller bearing 2, in the 1st region 46d of inner ring 46 and the 3rd region 40d of outer ring 40, be not provided with rib.Namely, tapered roller bearing 2 does not have in tapered roller bearing in the past in order to the necessary rib of the movement limiting roller.In the prior art, in order to reduce the friction between rib and the end face of roller, must grind the surface of rib.Therefore, the processing that the surface of rib is ground is needed.Gear drive 100 processing cost that can reduce inner ring and outer ring compared with the past.

In addition, the axial length of roller 42 can being made to extend the length corresponding to not having rib, the rolling surface of roller 42 can be widened.Its result, can increase the capacity (load) of tapered roller bearing 2.Namely, compared with the past, gear drive 100 can not increase the size of main bearing (tapered roller bearing 2), just can increase the capacity of main bearing.

With reference to Fig. 6, further illustrate other advantages of gear drive 100.Fig. 6 is the figure of the action of when rotating relative to static housing 4 for illustration of support 10, roller 42 and retainer 44.In addition, Fig. 6 is the figure of the concept of action for illustration of roller 42 and retainer 44, is not the figure of the structure for presenting gear drive 100 exactly.In addition, as mentioned above, can say that the inner ring 46 of tapered roller bearing 2 is integrated with support 10.Similarly can say that outer ring 40 is integrated with housing 4.Therefore, in figure 6, inner ring 46 and support 10 are expressed as component, outer ring 40 and housing 4 are expressed as component.In addition, the roller 42 shown in Fig. 6 presents the cross section orthogonal with running shaft direction.

When support 10 rotates to arrow A 1 direction, roller 42 rotates while move to arrow A 3 direction to arrow A 2 direction.Namely, roller 42 while roll while move to arrow A 3 direction on the outer circumferential face of support 10 and the inner peripheral surface of housing 4.Retainer 44 rotates to arrow A 3 direction together with the movement of roller 42.In this case, if roller 42 and the friction between support 10 and housing 4 less, then retainer 44 rotates with the rotating speed of the roughly half of the rotating speed V of support 10 (rotating speed 0.5V).If the friction between roller 42 and support 10 becomes greatly, then the speed of roller 42 is close to the speed of support 10.On the contrary, if friction between roller 42 and housing 4 becomes large, then the speed of roller 42 is close to the speed (zero) of housing 4.

As mentioned above, the 1st end 44a of retainer 44 contacts with both supports 10 with housing 4 (also with reference to Fig. 2).When retainer 44 contacts with both supports 10 with housing 4, between retainer 44 and housing 4, produce frictional force F1 along arrow A 4 direction.In addition, between retainer 44 and support 10, frictional force F2 is produced along arrow A 5 direction.The area of contact W1 that retainer 44 contacts with housing 4 is substantially equal to the area of contact W2 that retainer 44 contacts with support 10, and therefore, frictional force F1 and frictional force F2 is roughly equal.Frictional force F1 and frictional force F2 cancels out each other, and retainer 44 rotates along arrow A 3 direction with the speed close to rotating speed 0.5V.Roller 42 also moves along arrow A 3 direction with the speed close to rotating speed 0.5V.

As mentioned above, roller 42 with move close to the speed of rotating speed 0.5V mean roller 42 and the friction between support 10 and housing 4 less.In other words, roller 42 is less relative to the slip of support 10 and housing 4.Therefore, the wearing and tearing of the outer circumferential face (rolling surface) of roller 42 are suppressed.In addition, when such as retainer 44 only contacts with housing 4, only produce the frictional force suitable with the frictional force F1 of Fig. 6, the frictional force suitable with frictional force F2 cannot be obtained.Therefore, the rotating speed of retainer 44 is slack-off, and the friction between roller 42 and housing 4 becomes large.Promote the wearing and tearing of roller 42, the durability of gear drive reduces.Gear drive 100 shown in the present embodiment contacts with both housings 4 with support 10 by making retainer 44, thus can limit roller 42 to the wearing and tearing suppressing roller 42 while moving axially.

In addition, the tapered roller bearing 2 be configured between housing 4 and the 1st plate 10a has the feature identical with the tapered roller bearing 2 be configured between housing 4 and the 2nd plate 10c.Therefore, the explanation to the tapered roller bearing 2 be configured between housing 4 and the 1st plate 10a is omitted.

Further illustrate the advantage of gear drive 100.As mentioned above, the surface of contact that retainer 44 contacts with housing 4 is in concentric cylndrical surface with axis 30.In addition, retainer 44 is orthogonal with axis 30 with the surface of contact that support 10 contacts.By having such feature, the movement of retainer 44 is upper restrained in orthogonal both direction (axial and radial).Can reliably prevent retainer 44 (roller 42) from coming off to the outside of gear drive 100.

Retainer 44 contacts with both supports 10 with housing 4.Therefore, it is possible to utilize retainer 44 to be mixed in housing 4 to suppress foreign matter from the outside of gear drive 100.Further, the surface of contact (body contact face 44d) that housing 4 contacts with retainer 44 is formed with circumferential groove 44f, the surface of contact (support surface of contact 44e) that support 10 contacts with retainer 44 is formed with end face groove 44g.Therefore, even if retainer 44 contacts with both supports 10 with housing 4, the oiling agent being present in the outside of tapered roller bearing 2 also can import the inside of tapered roller bearing 2.The oiling agent exhaustion (oil starvation) in tapered roller bearing 2 can be suppressed.

When there being the power making roller 42 movement laterally to roller 42 effect, retainer 44 is pressed against housing 4 and support 10.As mentioned above, retainer 44 is resinous, and housing 4 and support 10 are metal.Namely, the rigidity of retainer 44 is lower than the rigidity of housing 4 and support 10.Therefore, when retainer 44 is pressed against housing 4 and support 10, retainer 44 is out of shape, and the entirety of the circumference of retainer 44 contacts with support 10 equably with housing 4.Namely, be difficult to form gap between body contact face 44d and housing 4 and between support surface of contact 44e and support 10.

Between housing 4 and the 1st plate 10a, be configured with oil sealing 6, be provided with groove 26 (with reference to Fig. 1) in the position relative with the 2nd plate 10c of housing 4.In groove 26, O-ring seals (diagram is omitted) is configured when installing other component (such as motor).Oil sealing 6 and not shown O-ring seals can be utilized, prevent from being sealed in oiling agent in gear drive 100 to gear drive 100 external leakage.The oiling agent being present in the vicinity of oil sealing 6 can import the inside of tapered roller bearing 2 via circumferential groove 44f and end face groove 44g.

(the 2nd embodiment)

The gear drive of the 2nd embodiment is described with reference to Fig. 7,8.The gear drive of the present embodiment is only that the shape of retainer is different from the shape of the retainer of gear drive 100.Specifically, the position relationship between the circumferential groove being formed at body contact face of the position relationship between the circumferential groove being formed at body contact face of the retainer 144 of the present embodiment and the end face groove being formed at support surface of contact and retainer 44 and the end face groove being formed at support surface of contact is different.Identical reference character is marked for common feature in retainer 144 and retainer 44, omits the description.

In the circumference of retainer 144, circumferential groove 44f and end face groove 44g is formed in same position.Therefore, circumferential groove 44f and end face groove 44g is continuous.The oiling agent being present in the outside of tapered roller bearing 2 can import the inside of tapered roller bearing 2 via circumferential groove 44f and end face groove 44g.By adopting retainer 144, oiling agent is more prone to the inside importing tapered roller bearing 2.

(the 3rd embodiment)

The gear drive of the 3rd embodiment is described with reference to Fig. 9,10.The shape of the gear drive of the present embodiment only retainer is different from the shape of the retainer of gear drive 100.Specifically, the shape being formed at the circumferential groove in body contact face of the retainer 244 of the present embodiment is different with the shape of the end face groove being formed at support surface of contact from the shape being formed at the circumferential groove in body contact face of retainer 44 with the shape of end face groove being formed at support surface of contact.For the reference character that feature common in retainer 244 with retainer 44 mark is identical or rear double figures is identical, omit the description.

As shown in Figure 9, support surface of contact 244e is formed with multiple end face groove 244g.When observing end face groove 244g from bearing central axis 30 direction, end face groove 244g extend towards having angle (relatively and reference Fig. 4) relative to straight line outer circumferential face (body contact face 244d) and the bearing central axis 30 of retainer 244 linked up.Multiple end face groove 244g is respectively to inclined.In addition, as shown in Figure 10, body contact face 244d is formed with multiple circumferential groove 244f.When observing circumferential groove 244f from the direction orthogonal with bearing central axis 30, all groove 244f extend towards having angle (relatively and with reference to Fig. 5) relative to bearing central axis 30.Multiple circumferential groove 244f is respectively to inclined.In addition, end face groove 244g and circumferential groove 244f is alternately formed in the circumference of retainer 44.Namely, end face groove 244g is formed between adjacent circumferential groove 244f, and circumferential groove 244f is formed between adjacent end face groove 244g.

When actuation gear transmission device 100, retainer 244 rotates relative to support 10 and housing 4.When end face groove 244g tilts, along with the rotation of retainer 244, oiling agent can move in end face groove 244g swimmingly along end face groove 244g.Similarly when circumferential groove 244f tilts, along with the rotation of retainer 244, oiling agent can move in circumferential groove 244f swimmingly along circumferential groove 244f.In addition, also can as retainer 144 end face groove 244g and circumferential groove 244f continuous.

(the 4th embodiment)

With reference to Figure 11, gear drive 300 is described.Gear drive 300 is variation of gear drive 100, by marking the identical reference character of identical or rear double figures to the component identical with gear drive 100, omits the description.

In gear drive 300, be provided with rake 346 in the longitudinal end of the 1st plate 310a and the 2nd plate 310c.Rake 346 is also used as the inner ring of tapered roller bearing 302.Namely, the inner ring of tapered roller bearing 302 is integrated with support 310.Such form is alternatively that inner ring is installed on support 310.Flange 310d is formed in the outside of the rake 346 of the 1st plate 310a.Flange 310e is formed in the outside of the rake 346 of the 2nd plate 310c.Retainer 44 is identical with retainer used in gear drive 100.Therefore, retainer 44 contacts with flange 310e with flange 310d on axis 30 direction, and the direction orthogonal with axis 30 contacts with housing 4.In addition, also retainer 44 be can substitute and retainer 144 or retainer 244 used.

In the above-described embodiments, the example that retainer and the area of contact of body contact equal the area of contact that retainer contacts with support is described.But, such as, retainer and the area of contact of the body contact area of contact that also can contact with support than retainer is large.On the contrary, the area of contact that retainer contacts with support also can be larger than the area of contact of retainer and body contact.Even such form, compared with situation about only contacting with housing or support with retainer, the friction of the outer circumferential face of roller can be reduced.

In the above-described embodiments, describing housing is the example that static, support rotates relative to housing.It is the gear drive that static, housing rotates relative to support that disclosed in this manual technology also can be applied to support.In addition, the gear drive that the technology disclosed in this specification configures with also can being applied to the axis coaxle of bent axle and support.Further, the technology disclosed in this specification also can be applied to the gear drive different from eccentric oscillating-type.

In the 4th embodiment, describe the example that support is also used as inner ring.Also outer ring can be also used as by housing.In addition, while also support can being also used as inner ring, housing is also used as outer ring.Importantly, between housing and support, be provided with tapered roller bearing, the running shaft of the roller of tapered roller bearing tilts relative to the axis of support, and inner ring and outer ring are not formed the rib of the movement laterally of restriction roller.

Below understand concrete example of the present invention in detail, but these just illustrating, is not limit protection scope of the present invention.Concrete example concrete example illustrated above being carried out various distortion, changes is comprised in the technology recorded in detail in the claims.The technical characteristics illustrated in this specification or accompanying drawing can play technical serviceability individually or play technical serviceability by various combination, is not limited to the combination described in claim when applying for.In addition, in this specification or accompanying drawing, illustrative technology can reach multiple object simultaneously, the serviceability on the technology itself reaching one of them object also possesses skills.

Claims

1. a gear drive, wherein, support is supported on housing by tapered roller bearing, wherein,

Described tapered roller bearing comprises:

Inner ring, it is installed on support;

Outer ring, it is installed on housing;

Multiple tapered roller, it is configured between inner ring and outer ring; And

The retainer of ring-type, it is configured between inner ring and outer ring, for maintaining the interval between adjacent tapered roller,

The minor diameter part of tapered roller is positioned at than the position of large-diameter portion by bearing centre axle side,

The outer circumferential face of inner ring and the inner peripheral surface of outer ring are not provided with for limiting tapered roller along the rib of direction movement leaving bearing central axis,

Retainer is formed by the material that rigidity is lower than the rigidity of support and housing, the support surface of contact that the direction of axle line within the bearing contacts with support is provided with in the end that its diameter is larger, further, the body contact face with body contact on the direction orthogonal with bearing central axis is provided with.

2. gear drive according to claim 1, wherein,

At least one in described support surface of contact and described body contact face is formed with groove.

3. gear drive according to claim 2, wherein,

Described support surface of contact and described both body contact faces are formed with groove.

4. gear drive according to claim 3, wherein,

The 1st groove being located at described support surface of contact and the 2nd groove being located at described body contact face alternately configure in the circumference of described retainer.

5. gear drive according to claim 3, wherein,

The 1st groove being located at described support surface of contact and the 2nd groove being located at described body contact face are configured at the same position in the circumference of described retainer,

1st groove and the 2nd groove continuous.

6. the gear drive according to any one of claim 3 ~ 5, wherein,

When observing from the direction of bearing central axis, the 1st groove has angle relative to straight line bearing central axis and retainer linked up,

When observing from the direction orthogonal with bearing central axis, the 2nd groove has angle relative to bearing central axis.

7. the gear drive according to any one of claim 1 ~ 6, is characterized in that,

The material of retainer is resin.