JP2014148989A - Speed reducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely align shaft centers of a front stage and rear stage members connected via a speed reducer with each other, and to reduce processing cost.SOLUTION: In a speed reducer 10 with a casing 31, the casing 31 is provided with a single spigot face 17, into which both of an adaptor 54 being a front stage member of the speed reducer 10 and a base plate 50 being a rear stage member of the speed reducer 10 are spigot-fitted.

Description

  The present invention relates to a reduction gear.

  Patent Document 1 discloses a reduction gear including an output side casing as a casing. The output side casing is provided with spigot portions on the outer periphery of the output side end portion and the inner periphery of the input side end portion. A mating machine as a rear-stage side member is fitted into the spigot portion on the outer periphery of the output side end portion. An input side casing as a front-stage side member is fitted into a spigot portion on the inner periphery of the input side end portion.

JP 2011-52785 A

  In the casing of the reduction gear of Patent Document 1, the inlay portion with the rear stage side member is formed on the output side end portion outer periphery, and the inlay portion with the front stage side member is formed on the input side end portion inner periphery. There is a problem that it is necessary to process the inlay part separately, and it is difficult to accurately match the axial centers of the front-stage member and the rear-stage member, and the processing cost is increased.

  The present invention has been made to solve such a conventional problem, and can accurately match the axes of the front-stage side member and the rear-stage side member connected via the reduction gear, and An object of the present invention is to provide a reduction gear that can reduce the processing cost.

  The present invention is a reduction gear provided with a casing, wherein a single inlay surface is provided on the casing, and a front side member of the reduction device and a rear side member of the reduction device are provided on the single inlay surface. Both of these are solved by the above-mentioned inlay fitting.

  In the present invention, both the front stage side member and the rear stage side member of the speed reducer are fitted in a single spigot surface formed on the casing of the speed reducer. For this reason, since the common inlay surface is used, the axial centers of the front-stage side member and the rear-stage side member can be made to coincide with each other with high accuracy, and machining can be performed only once, so that machining costs can be reduced.

  Further, the present invention is a speed reducer provided with a casing, wherein two inlay surfaces are formed apart from each other in the casing, and the two inlay surfaces have the same diameter and are between the two inlay surfaces. The above-mentioned problem is solved by forming in a state where there is no portion having a diameter larger than that of the inlay surface.

  ADVANTAGE OF THE INVENTION According to this invention, the axial center of the front | former stage side member and back | latter stage side member connected via a reduction gear can be made to correspond accurately, and processing cost can be reduced.

Sectional drawing which shows the structure of the reduction gear which concerns on an example of embodiment of this invention. FIG. 1 is a partially enlarged cross-sectional view taken along the line II of the reducer of FIG. Sectional drawing which shows the structure of the reduction gear which concerns on an example of other embodiment of this invention.

  Hereinafter, a reduction gear according to an example of an embodiment of the present invention will be described in detail with reference to the drawings.

  First, the overall schematic configuration of the speed reducer 10 will be described with reference to FIG.

  This speed reducer 10 is a speed reducer having an eccentric oscillating type speed reducing mechanism 11 and decelerates the rotation of a motor shaft 13A of a motor 13 to drive a not-shown driven body of a counterpart machine 15 (not shown). Used in a manner. The connection configuration between the motor 13 and the counterpart machine 15 via the spigot surface 17 of the speed reducer 10 will be described in detail later.

  The input shaft 12 of the speed reducer 10 is configured by a hollow shaft having a hollow portion 12A. The input shaft 12 is connected to the motor shaft 13A of the motor 13 via the key 12B. Eccentric bodies 14 and 16 are integrally formed on the input shaft 12.

  The axial centers O2 and O3 of the eccentric bodies 14 and 16 are eccentric with respect to the axial center O1 of the input shaft 12 by an eccentric amount Δe1. In this example, the eccentric phase difference between the eccentric bodies 14 and 16 is 180 degrees.

  Roller bearings 18 and 20 are arranged on the outer circumferences of the eccentric bodies 14 and 16. External gears (planetary gears) 22 and 24 are incorporated on the outer circumferences of the roller bearings 18 and 20 so as to be swingable. The external gears 22 and 24 are in mesh with the internal gear 26, respectively.

  The internal gear 26 is externally fitted to the internal gear main body 26A integrated with the casing 31, a cylindrical outer pin 26B supported by the internal gear main body 26A, and the outer pin 26B so as to be rotatable. The roller 26 </ b> C constituting the “inner teeth” of the tooth gear 26 is mainly configured. The number of internal teeth of the internal gear 26 (the number of rollers 26C) is slightly larger (only 1 in this example) than the number of external teeth of the external gears 22 and 24.

  The external gears 22 and 24 are provided with a plurality of (in this example, 10) through-holes 22A and 24A at positions offset from their axial centers (same as O2 and O3) at intervals of 36 degrees in the circumferential direction. It has been. A pair of carriers (flange members) 32 and 34 are arranged on both sides in the axial direction of the external gears 22 and 24. The carriers 32 and 34 are supported by the casing 31 via angular ball bearings 40 and 42. The angular ball bearings 40, 42 do not have a dedicated inner ring, and the outer peripheral portions of the carriers 32, 34 also serve as the inner rings of the angular ball bearings 40, 42. The carriers 32 and 34 support the input shaft 12 via bearings 35 and 37.

  An inner pin 28 is integrally formed so as to protrude from the carrier 34 on the load side. The inner pin 28 may be formed separately from the carrier 34 and connected to the carrier 34 by, for example, press fitting.

  In this embodiment, the inner pin 28 is formed so as to protrude by 10 corresponding to the through holes 22A and 24A of the external gears 22 and 24, and the through holes 22A and 24A of the external gears 22 and 24, respectively. It penetrates. The carrier 34 is integrated with the output shaft 48.

  The carrier 32 on the non-load side is formed with a recess 32D on the side surface of the carrier 32 on the external gear 22 and 24 side. The inner pin 28 connects the carrier 32 and the carrier 34 with a bolt 45 in a state in which the tip thereof is fitted in the recess 32D.

  Between the inner pin 28 and the external gears 22 and 24 (inner peripheral surfaces of the through holes 22A and 24A), a sliding roller 44 as a sliding acceleration member is disposed. The sliding roller 44 is always in contact with a part of the inner peripheral surface of the through holes 22A and 24A of the external gears 22 and 24, and is eccentric between the through holes 22A and 24A on the non-contact side. Clearances of a size (2 · Δe1) corresponding to twice the eccentricity Δe1 of the bodies 14 and 16 are secured.

  Next, a structure related to the inlay surface 17 of the speed reducer 10 will be described.

  The speed reducer 10 is used in a state where the motor 13 is connected to the input side and the whole is attached to the base plate 50 of the counterpart machine 15.

  The motor 13 has a motor casing 13 </ b> B fixed to the adapter 54 via a first bolt 52. The adapter 54 to which the motor 13 is fixed is attached to the speed reducer 10 via the second bolt 56. That is, in the present embodiment, the adapter 54 corresponds to the front side member.

  In the present embodiment, the adapter 54 is located between the motor 13 and the speed reducer 10 and has a function as a joint member that connects the motor 13 and the speed reducer 10 and also functions as a front casing of the speed reducer 10. I also have a double use.

  For this reason, the adapter 54 has a function of sealing the lubricant in the speed reducer 10 as a part of the casing 31 of the speed reducer 10, and is attached to the outer ring 40 </ b> A of the angular ball bearing 40 of the speed reducer 10. It is fitted. However, when the adapter 54 is connected to the casing 31 (the casing body 58) of the speed reducer 10, in order to avoid the occurrence of interference due to having two spigot portions, as shown in FIG. The fitting between the outer ring 40 </ b> A of the angular ball bearing 40 and the adapter 54 is a non-inlay fitting in which the gap δ is larger than the inlay fitting on the inlay surface 17. In addition, as a part of the casing 31 of the speed reducer 10, an O-ring 70 is provided at the fitting portion of the outer ring 40 </ b> A of the angular ball bearing 40 in order to ensure the sealing of the lubricant in the speed reducer 10. It is arranged. Specifically, a key-shaped recess 54 </ b> B is formed on the inner peripheral side of the end surface 54 </ b> A of the adapter 54 that faces the axial end surface 58 </ b> A of the casing body 58. The O-ring 70 is incorporated in the recess 54B and abuts on a total of four surfaces of the casing main body 58, the adapter 54, and the three members of the outer ring 40A of the angular ball bearing 40 located on the inner peripheral side of the adapter 54. The inside and outside of the speed reducer 10 are sealed.

  The casing 31 of the speed reducer 10 includes the adapter 54 functioning as a front casing, a casing body 58, and a load side cover 60, and is fastened together by a second bolt 56. The casing body 58 accommodates the eccentric oscillating speed reduction mechanism 11, and the load side cover 60 mainly accommodates the carrier 34 and the output shaft 48.

  Here, in this embodiment, the spigot surface 17 according to the present invention is formed in a band shape on the outer periphery of the end portion of the casing body 58 on the adapter 54 side.

  The inlay surface 17 has an outer diameter d2 that is slightly larger than the outer diameter d1 of the casing body 58, and is finished.

  The length of the inlay surface 17 in the axial direction is L1, and the axial length L2 that is substantially half of the length on the adapter 54 side is the front-side inlay surface 17A that contributes to the fitting of the adapter 54. Moreover, the axial direction length L3 of almost half of the remaining non-adapter side is a rear-stage side spigot surface 17B that contributes to the fitting of the base plate 50 of the counterpart machine 15. That is, in the present embodiment, the base plate 50 of the counterpart machine 15 corresponds to a “rear stage member”.

  In the present embodiment, the adapter 54 that is the front side member and the base plate 50 of the counterpart machine 15 that is the rear side member are fastened together by the third bolt 72. In the present embodiment, the adapter 54 and the base plate 50 are members that do not rotate relative to each other.

  However, the adapter 54 and the base plate 50 are not necessarily in a fixed state. That is, when the reduction gear 10 is viewed as a single unit, the casing 31 is generally a fixed body and the output shaft 48 is a rotating body, and therefore the adapter 54 and the base plate 50 are fixed bodies. However, depending on the application, when the speed reducer 10 is used, for example, in a joint portion of an industrial multi-axis robot, the casing 31 and the output shaft 48 are members that rotate relative to each other. It cannot be determined which is fixed or which is rotating. That is, depending on the actual manner of attachment of the speed reducer 10, it may be understood that the adapter 54 and the base plate 50 themselves rotate relative to the output shaft 48 of the speed reducer 10. In other words, it does not matter whether the adapter 54 and the base plate 50 according to the present embodiment are rotating bodies or fixed bodies.

  Next, the operation of the speed reducer 10 will be described.

  First, the operation of the eccentric oscillating speed reduction mechanism 11 will be described.

  When the input shaft 12 rotates, the eccentric bodies 14 and 16 integrated with the input shaft 12 rotate eccentrically, and external teeth incorporated on the outer periphery of the eccentric bodies 14 and 16 via roller bearings 18 and 20. The gears 22 and 24 are swung with a phase difference of 180 degrees. The external gears 22 and 24 are in mesh with the internal gear 26, and the internal gear main body 26 </ b> A is integrated with the casing 31 in this embodiment. Therefore, each time the input shaft 12 rotates once, the external gears 22 and 24 rotate relative to the internal gear 26 (casing 31) by a difference in the number of teeth (one tooth in this example) (rotate). ).

  The rotation components of the external gears 22 and 24 are transmitted to the carriers 32 and 34 via the sliding rollers 44 and the inner pins 28 that pass through the through holes 22A and 24A of the external gears 22 and 24, respectively. , 34 rotate relative to the casing 31 at the same speed as the rotation components of the external gears 22, 24. As a result, the output (rotating relative to the casing 31) can be taken out from the output shaft 48 integrated with the carrier 34.

  Here, in this embodiment, the motor 13 is connected to the adapter 54 by the first bolt 52, and the adapter 54 to which the motor 13 is connected is a single unit formed on the outer periphery of the casing body 58 of the speed reducer 10. The inlay surface 17 is externally fitted to the front-side inlay surface 17A of the almost half portion on the axial adapter side, is fastened together with the second bolt 56, and is connected to the casing body 58 of the speed reducer 10.

  On the other hand, the base plate 50 of the mating machine 15 is externally fitted to the rear side inlay surface 17B of the substantially half portion of the same inlay surface 17 on the opposite side in the axial direction, and is fastened together with the adapter 54 through the third bolt 72. Connected at That is, in this embodiment, the adapter 54 and the base plate 50 do not rotate relative to each other, and the connection is also direct and strong.

  The adapter 54 and the base plate 50 are connected to each other while maintaining a common axis (same as O1) by being inlay-fitted (externally fitted) to the same inlay surface 17. Accordingly, as a result, a connection in which the axis (O1) of the motor 13 and the axis (O1) of the driven body of the counterpart machine 15 are more accurately matched (despite the reduction gear 10 being interposed) is achieved. It becomes possible.

  In short, the deviation of the axis (O1) of the motor 13 and the speed reducer 10 and the deviation of the axis (O1) of the speed reducer 10 and the counterpart machine 15 are usually “accumulated”. Then, since the motor 13 and the counterpart machine 15 are directly defined by the same inlay surface 17, the shaft center (O1) between the motor 13 and the counterpart machine 15 is interposed while the speed reducer 10 is interposed in the middle. This means that accumulation of deviation does not occur. The characteristic that this deviation does not accumulate is that it is incorporated into a device having a configuration in which a plurality of axes are connected in series, such as an industrial robot having a multi-axis (for example, six axes) degree of freedom. It is especially beneficial when.

  In addition, since the inlay surface 17 itself having the functions of the two inlay surfaces is single (one), the processing is only required once, and the processing cost can be greatly reduced.

  The adapter 54 has a partial function of the casing 31 of the speed reducer 10 and is externally fitted to the angular ball bearing 40, but the externally fitted portion is more than the inlay fit on the inlay surface 17. Since it is a non-inlay fitting with a large gap δ, no interference occurs between the two fitting portions, and an O-ring 70 is interposed in the fitting portion of the outer ring 40A of the angular ball bearing 40. Therefore, the sealing function of the lubricant in the speed reducer 10 is not impaired.

  FIG. 3 shows an example of another embodiment of the present invention.

  In this embodiment, two inlay surfaces 117A and 117B are formed apart from each other as the inlay surface 117 in the casing 131 of the speed reducer 110 similar to the previous embodiment. The two spigot surfaces 117A and 117B have the same diameter d102, and are formed between the two spigot surfaces 117A and 117B in a state where there is no portion having a larger diameter than the spigot surfaces 117A and 117B. ing. More specifically, the inlay surfaces 117 </ b> A and 117 </ b> B are formed to project from the outer periphery of the casing main body 158 in a band shape with an interval L <b> 104. The casing body 158 has an outer diameter d101 on the axial adapter side of the spigot surface 117A, between the spigot surfaces 117A and 117B, and on the anti-adapter side of the spigot surface 117B, and the spigot surface 117A, There is no portion having an outer diameter larger than the outer diameter d102 of 117B. For this reason, the inlay surfaces 117A and 117B can be simultaneously formed from one side in the axial direction by one processing (processing by the same tool by the same chucking). Therefore, it can be regarded as substantially the same inlay surface, and there is almost no deviation between the two inlay surfaces 117A, 117B. In addition, the processing cost can be reduced.

  Furthermore, the configuration according to this embodiment can ensure a substantial formation length (axial length) L101 of the inlay surface 117, so that the concentricity between the adapter 154 of the front-stage side member and the base plate 150 of the rear-stage side member can be increased. Further improvement can be achieved.

  Further, since the machining of the center portion of the inlay surface 117 can be omitted, the machining allowance (machining allowance) at the time of machining can be reduced, and the inlay surface (117) having the same axial length L101 can be continuously formed. Compared with the case of forming in this way, the tool life can be further extended, the machining time can be further shortened, and the machining cost can be further reduced.

  Since the other configuration is the same as that of the previous embodiment, the same or functionally the same member as that of the previous embodiment is given the same reference numeral in the last two digits as in the previous embodiment. Duplicate explanation is omitted.

  Here, the front side member and the rear side member according to the present invention will be supplemented slightly.

  Examples of the “front member” arranged upstream on the power transmission path of the speed reducer according to the present invention include a front speed reducer, a coupling device, and the like, in addition to a motor as a drive source. In the “front-stage member” according to the present invention, in addition to these front-stage members themselves, members for connecting the front-stage members to the speed reducer, for example, the motor that is the front-stage member as in the previous embodiment, When it is connected to the speed reducer via an adapter (joint member), a “member for connecting the preceding member” such as the adapter is included.

  Further, the concept of the “front stage side member” includes not only a member completely independent of the speed reducer but also one of the components of the speed reducer in a state where it is connected to the speed reducer like the adapter 54 in the previous embodiment. The member used as a part is contained.

  Similarly, the “rear stage member” disposed downstream on the power transmission path of the speed reducer includes, for example, a rear stage speed reducer, a coupling device, and the like, in addition to the counterpart machine to be driven. The “rear stage member” referred to in the present invention includes, in addition to these rear stage members themselves, members for connecting the rear stage members to the speed reducer.

  Further, although not adopted in the previous embodiment, like the “front-stage side member”, the concept of the “rear-stage side member” of the present invention includes a member that is completely independent of the speed reducer. The concept of a member that is a part of the components of the speed reducer when the speed reducer is connected is included. Therefore, for example, the speed reducer may be organically incorporated in the counterpart machine, and a part of the counterpart machine may be configured as a part of the casing of the speed reducer as it is.

  Further, as already mentioned, depending on the actual mounting mode, the front-stage member and the rear-stage member fitted to the inlay surface may be understood as rotating relative to the output shaft of the speed reducer. . In other words, it does not matter whether the front-stage member and the rear-stage member according to the present invention are rotating bodies or fixed bodies.

  Furthermore, in the previous embodiment, the front-stage side member and the rear-stage side member are fastened together, but the front-stage side member and the rear-stage side member according to the present invention do not necessarily have to be fastened together. You may connect with the casing of the reduction gear with the volt | bolt. In the first place, one of the front side member and the rear side member may rotate relative to the other. For example, one of the front stage side member and the rear stage side member is integrally connected to the casing of the speed reducer via the spigot surface, and the other is connected to the output shaft 48 (for example, the previous embodiment). According to the present invention, it may be configured to rotate relative to the casing of the speed reducer in the aspect of the inlay surface in the form of a sliding bearing.

  Further, in the previous embodiment, when the front side member has another fitting surface in addition to the inlay surface, the other fitting surface is substantially non-inlay fitted with a large gap. However, the present invention does not prohibit the presence of another inlay surface in addition to the inlay surface. You may comprise so that a front | former stage side member (or back | latter stage side member) may be assembled | attached more correctly using this inlay surface.

  The speed reducer according to the present invention is particularly effective when the input shaft and the output shaft are coaxial as in the previous embodiment, but in the present invention, both the front side member and the rear side member are It is only necessary to have a fitting surface that can be fitted to a single or common (same diameter) inlay surface, and the structure of the reduction mechanism of the reduction gear is not particularly limited. For example, a simple planetary gear reduction mechanism, a parallel shaft A reduction mechanism, an orthogonal reduction mechanism, or a combination thereof may be used.

DESCRIPTION OF SYMBOLS 10 ... Reduction gear 17 ... Inner surface 17A ... Front side inlay surface 17B ... Rear side inlay surface 31 ... Casing 50 ... Base plate (rear side member)
54 ... Adapter (front side member)

Claims (5)

A speed reducer with a casing,
A single inlay surface is provided in the casing;
Both the front side member of the speed reducer and the rear side member of the speed reducer are inlay-fitted to the single inlay surface. In claim 1,
The speed reducer, wherein the front side member and the rear side member fitted to the single inlay surface are fastened together. In claim 1 or 2,
At least one of the front stage side member and the rear stage side member is also fitted to the outer ring of the bearing of the speed reducer, and the outer fit is a fit with a larger gap than the fit on the single spigot surface. A speed reducer characterized by that. In claim 3,
An O-ring is interposed in the fitting portion of the outer ring of the bearing. A speed reducer with a casing,
Two inlay surfaces are formed on the casing apart from each other,
The two spigot surfaces have the same diameter, and are formed in a state where no portion having a larger diameter than the spigot surface exists between the two spigot surfaces.

Images