JP6124767B2 - Gear unit series - Google Patents

Description

  The present invention relates to a series of gear devices.

  Patent Document 1 discloses an eccentric oscillating gear device that internally meshes with an internal gear while the external gear is oscillating, and extracts the relative rotation between the external gear and the internal gear as a deceleration output. Yes.

  The internal gear in this gear device includes an internal gear main body and a plurality of pin members arranged on the internal gear main body, and the pin members constitute internal teeth of the internal gear.

  The internal gear main body is provided with a holding hole for holding the pin member, and the pin member is provided in the internal gear main body in such a manner that the entire circumference of a part of the side surface in the axial direction is held by the holding hole. Is retained.

Japanese Patent Publication No. 8-6784 (Fig. 4)

  The reduction ratio of the gear device having such an internal gear is determined depending on the difference in the number of teeth between the external gear and the internal gear and the number of teeth. When the number of teeth is the same, the gear unit with a high reduction ratio tends to have a larger number of internal teeth (number of pin members) and a smaller diameter of the pin member than a gear device with a reduced speed ratio. . For this reason, the gear unit with a high reduction ratio has a problem in that a large number of small-diameter holding holes have to be machined when machining the holding holes for holding the pin member of the internal gear body, which increases the machining cost. .

  The present invention has been made to solve such a conventional problem, and provides a gear device series capable of configuring a gear device having a reduced speed ratio to a high reduction ratio at a lower cost. That is the issue.

  The present invention includes an internal gear main body, an internal gear having a plurality of pin members arranged on the internal gear main body, the pin member constituting internal teeth, and a cover member connected to the internal gear main body. A gear unit including a first gear unit and a second gear unit, wherein the cover member is common to the first gear unit and the second gear unit. A holding groove for holding the pin member is provided, the second gear device has more pin members than the first gear device, and the pin member of the second gear device is the first gear device. The internal gear main body of the first gear device has a holding hole that holds a part of the entire circumference of the side surface of the pin member in the axial direction. The pin member of the gear device is not held in the holding groove of the cover member, The internal gear main body of the second gear device is not provided with a holding hole for the pin member, and the pin member of the second gear device is the cover member. The above-mentioned problem is solved by adopting a configuration that is held in the holding groove.

  The gear device series of the present invention includes a first gear device having a small number of pin members (small number of internal teeth) and a large diameter, and a large number of pin members (large number of internal teeth). ) A second gear device with a small diameter is included as its component.

  The first gear device and the second gear device share a cover member that is connected to the internal gear main body. The cover member is provided with a holding groove for holding the pin member. And in this series, the holding hole which hold | maintains one part side surface perimeter of the axial direction of a pin member is formed only in the internal gear main body of a 1st gear apparatus.

  In addition, the pin member of the first gear device is not held in the holding groove of the cover member but is held in the holding hole of the internal gear main body, while the pin member of the second gear device is held by the cover member. It is configured to be held in the groove.

  Thereby, both the first gear device and the second gear device can be manufactured at low cost.

  ADVANTAGE OF THE INVENTION According to this invention, the gear apparatus series which can comprise the gear apparatus of reduction speed ratio-high reduction ratio at lower cost can be obtained.

Sectional drawing which shows the whole structure of the 1st gear apparatus of the series of the gear apparatus which concerns on an example of embodiment of this invention. Partial enlarged sectional view taken along line II-II in FIG. The partial expanded sectional view which shows the structure of the vicinity of the internal gear of FIG. The partial expanded sectional view which shows the structure of the vicinity of the internal gear of the 2nd gear apparatus of the said gear apparatus series. Sectional view along line VV in FIG. Sectional view along line VI-VI in FIG.

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

  If it demonstrates from an outline, the series of the gear apparatus in this invention will contain the 1st gear apparatus and the 2nd gear apparatus with which the internal tooth of the internal gear comprised the pin member as the component.

  Since the first gear device and the second gear device have a common configuration except that the peripheral structure of the internal gear is different, first, the overall configuration of the first gear device will be described first, and then Description will be made by paying attention to the difference between the first gear device and the second gear device.

  FIG. 1 is a cross-sectional view showing an overall configuration of a first gear device 110 of a series of gear devices according to an example of an embodiment of the present invention, and FIG. 2 is a partially enlarged cross-sectional view taken along line II-II in FIG. It is.

  The first gear device 110 internally meshes with the internal gear 116 while oscillating the two external gears 114 by the two eccentric bodies 112, and between the internal gear 116 and the external gear 114. The relative rotation that occurs is taken out as output.

  The input shaft 111 of the first gear device 110 is integrated with the motor shaft 120 of the motor 118. An eccentric body shaft 124 is connected to the input shaft 111 via a key 122. The two eccentric bodies 112 are integrally formed on the eccentric body shaft 124. An external gear 114 is incorporated in an outer periphery of the eccentric body 112 through an eccentric body bearing 126 so as to be swingable. The external gear 114 is in mesh with the internal gear 116 while swinging.

  That is, the first gear device 110 is an eccentric oscillating gear device called a central crank type in which only one eccentric body shaft 124 exists at the radial center of the internal gear 116. The reason why the two external gears 114 are provided in parallel is that it is intended to secure the necessary transmission capacity and to secure the rotational balance by shifting the eccentric phase.

  The tooth profile of the external gear 114 is a trochoidal tooth profile, and the tooth profile of the internal gear 116 is an arc tooth profile. As shown in an enlarged view in FIG. 3, the internal gear 116 includes an internal gear main body 117 integrated with the casing 128 and a plurality of cylindrical pins arranged on the internal gear main body 117 in this embodiment. The internal teeth of the arc tooth shape are constituted by pin members 119. A roller member 119S is externally fitted as a sliding acceleration member on the outer periphery of the pin member 119 in order to smoothly slide with the external gear 114. Therefore, in this embodiment, it can be considered that the roller member 119 </ b> S substantially constitutes the internal teeth of the internal gear 116. Thus, in the 1st gear apparatus 110 of this embodiment, the internal tooth is comprised by the pin member 119 by which the roller member 119S was externally fitted. In other words, in the present invention, “the pin member constitutes an internal tooth” is not limited to the case where the pin member itself directly constitutes an internal tooth, but the roller member is externally fitted to the pin member and the internal tooth is constituted by both. It is also included when doing.

  The number of internal teeth (the number of pin members 119 or roller members 119S) of the internal gear 116 is slightly larger (only 1 in this example) than the number of external teeth of the external gear 114.

  The configuration in the vicinity of the internal gear 116 will be described in detail later.

  The external gear 114 includes an internal pin hole 114 </ b> A that passes through the external gear 114. An inner pin 132 is loosely fitted in the inner pin hole 114A. An inner roller 138 is disposed on the outer periphery of the inner pin 132 as a sliding promotion member. A gap δ1 equivalent to twice the amount of eccentricity of the eccentric body 112 is secured between the inner roller 138 and the inner pin hole 114A. A flange body 134 is disposed on the axial side portion of the external gear 114, and the inner pin 132 is press-fitted and fixed in the inner pin holding hole 134 </ b> A of the flange body 134. The flange body 134 is integrated with the output shaft 136 (FIG. 1). The output shaft 136 is supported by a pair of tapered roller bearings 137.

  Next, the first gear device 110 and the second gear device 210 in the series of gear devices of the present embodiment will be described in detail. The members of the first gear device 110 are numbered in the 100s, the members of the second gear device 210 are numbered in the numbers of the 200s, and the second gears corresponding to the members of the first gear device 110 already described. The members of the apparatus 210 will be described by appropriately attaching the same reference numerals in the last two digits.

  In order to meet the various demands of users, a plurality of gear devices having different sizes (transmission capacity) and reduction ratios are often provided as “series”. The first gear device 110 and the second gear device 210 in the gear device series according to this embodiment have different reduction ratios, and the second gear device 210 has a higher reduction ratio (input shafts 111 and 211). The rotational speed of the output shaft 236 of the second gear device 210 is slower than the rotational speed of the output shaft 136 of the first gear device 110).

  In order to facilitate the understanding of the reduction ratio, first, the speed reduction action of the first gear device 110 will be briefly described. This deceleration action is the same in the second gear device 210.

  Referring to FIG. 1 again, when the input shaft 111 of the first gear device 110 integrated with the motor shaft 120 is rotated by the rotation of the motor shaft 120 of the motor 118, the input shaft 111 and The connected eccentric body shaft 124 rotates. When the eccentric body shaft 124 rotates, the eccentric body 112 formed integrally with the eccentric body shaft 124 rotates, and each time the input shaft 111 rotates once, the external gear 114 rotates via the eccentric body bearing 126. Oscillates once. As a result, a phenomenon occurs in which the meshing positions of the external gear 114 and the internal gear 116 are sequentially shifted, and the external gear 114 has a difference in the number of teeth from the internal gear 116, that is, “one tooth”. It rotates relative to the internal gear 116 in the fixed state (rotates). This rotation component is transmitted to the flange body 134 disposed on the side in the axial direction of the external gear 114 via the inner pin 132, and the output shaft 136 integrated with the flange body 134 rotates. As a result, it is possible to realize a reduction with a reduction ratio corresponding to (the number of teeth difference between the internal gear 116 and the external gear 114) / (the number of teeth of the external gear 114).

  In the first and second gear devices 110 and 210 of the gear device series according to the present embodiment, the difference in the number of teeth is “1”, so that the reduction ratio is 1 / (the external gears 114 and 214 of the external gears 114 and 214. The number of teeth), that is, 1 / (the number of teeth of the internal gears 116 and 216 −1).

  In other words, the first gear device 110 with the reduced speed ratio has a small number of internal teeth (the number of pin members) of the internal gear 116 and a large tooth length (the diameter of the pin member 119). On the contrary, the second gear device 210 having a high reduction ratio has a larger number of internal teeth of the internal gear 216 and a smaller tooth height (the diameter of the pin member 219) than the first gear device 110. That is, the second gear device 210 with a high reduction ratio has more pin members 219 than the first gear device 110 with a reduced speed ratio, and the pin member 219 of the second gear device 210 has the first gear device 110. The diameter of the pin member 119 is smaller.

  Conventionally, for internal gears, a holding hole into which a pin member can be fitted along the axial direction is first formed in the material of the internal gear body in the form of a through hole, and then the diameter of the holding hole is set. The inner portion in the direction was scraped off by cutting or the like to form a “pin groove” having a semicircular cross section, and the pin member and the external gear were meshed at the scraped portion. However, in this manufacturing method, when manufacturing the internal gear of the second gear device having a high reduction ratio, the number of holding holes to be formed is large, and “burrs” generated at the edge of the pin groove during cutting are removed. Since it was necessary, the processing man-hours became very large, and the problem that cost started had arisen.

  On the other hand, in recent years, a method of directly forming a pin groove having a semicircular cross section in a material that becomes an internal gear main body using a gear shaper has also been adopted. In this type of gear device, especially when the difference in the number of teeth is “1”, the pin member is disposed between the pin groove and the external gear, so that even in this method, the pin member is detached from the pin groove. There is no end to it. However, in this method, since the pin member is simply disposed between the pin groove and the external gear, the pin member easily moves in the radial direction along with the eccentric oscillation of the external gear. There was a problem that noise may occur.

  Therefore, in the series of gear devices according to this embodiment, the internal gears 116 and 216 of the first gear device 110 and the second gear device 210, in particular, are formed with the following configuration (commonization or differentiation). ), Both of them can be manufactured easily and at low cost.

  3 is a partially enlarged cross-sectional view showing the configuration of the vicinity of the internal gear 116 of the first gear device 110 as described above, and FIG. 4 is a diagram of the vicinity of the internal gear 216 of the second gear device 210. It is a partial expanded sectional view which shows a structure.

  First, from the configuration shared by the first gear device 110 and the second gear device 210, the internal gears 116 and 216 of the first gear device 110 and the second gear device 210 are both internal teeth. It has the gear main bodies 117 and 217 and a plurality of pin members 119 and 219 disposed on the internal gear main bodies 117 and 217, and the pin members 119 and 219 constitute internal teeth.

  The cover members 150 and 250 are connected to the internal gear main bodies 117 and 217 via bolts 152 and 252 from both sides in the axial direction. Specifically, the cover members 150 and 250 include load-side cover members 150A and 250A disposed on the axial load side with respect to the internal gears 116 and 216, and an axial anti-load with respect to the internal gears 116 and 216. It is comprised by the anti-load side cover members 150B and 250B arrange | positioned at the side, respectively. The cover members 150 and 250 are common to the first gear device 110 and the second gear device 210.

  Specifically, the load-side cover member 150A of the first gear device 110 and the load-side cover member 250A of the second gear device 210 are common, and the anti-load-side cover member 150B and the second gear of the first gear device 110 are common. The anti-load side cover members 250B of the device 210 are common.

  The cover members 150 and 250 (the load side cover members 150A and 250A and the anti-load side cover members 150B and 250B) are provided with holding grooves 160 and 260 for holding the pin members 119 and 219, respectively.

  Specifically, the load-side cover members 150A and 250A of the first and second gear devices 110 and 210 are formed into endless ring shapes by cutting from the anti-load side to the surfaces 150A1 and 250A1 on the axially anti-load side. The load side holding grooves 160A and 260A are formed. Further, the anti-load side cover members 150B and 250B of the first and second gear devices 110 and 210 are provided on the anti-load side formed in an endless ring shape by cutting from the load side to the surfaces 150B1 and 250B1 on the axial load side. Holding grooves 160B and 260B are respectively formed.

  The load side cover members 150A and 250A and the anti-load side cover members 150B and 250B of the first and second gear devices 110 and 210 include the load-side holding grooves 160A and 260A and the anti-load side holding grooves 160B and 260B. It is common.

  The internal gear main bodies 117 and 217 also serve as the casing main bodies of the first and second gear devices 110 and 210. The internal gear main bodies 117 and 217 and the first and second cover members 150 and 250 1. The casing of the 1st, 2nd gear apparatus 110 and 210 is comprised. Thereby, since the large sized member (or raw material) which comprises a casing can be shared, the big cost reduction effect is acquired.

  Next, the first gear device 110 and the second gear device 210 are differentiated as follows.

  The internal gear main body 117 of the first gear device 110 has a holding hole (through hole) 164 that holds the entire side surface of the part 119A, 119B in the axial direction of the pin member 119. Specifically, a load side holding hole 164A is provided on the load side of the external gear 114, and an antiload side holding hole 164B is provided on the antiload side of the external gear 114. The pin member 119 of the first gear device 110 is not held in the load side and anti-load side holding grooves 160A and 160B of the load side and anti-load side cover members 150A and 150B described above, but the holding of the internal gear main body 117. Both ends are held in the holes 164 (the load side holding holes 164A and the anti-load side holding holes 164B).

  In this embodiment, since the roller member 119S that is a sliding acceleration member is externally fitted to the pin member 119, the both-end support of the pin member 119 is supported more reliably as an intermediate fit. I have to. However, as a matter of course, the pin member 119 itself may be rotated as a clearance fit.

  On the other hand, as shown in an enlarged view in FIG. 4, the internal gear main body 217 of the second gear device 210 is not provided with a holding hole for the pin member 219. Only a pin groove 215 having a semicircular cross section for restricting the circumferential position of the pin member 219 is formed by a gear shaper or the like. The pin member 219 of the second gear device 210 is held at both ends in the holding grooves 260 (the load-side holding groove 260A and the anti-load-side holding groove 260B) of the load-side and anti-load-side cover members 250A, 250B. Directional movement is constrained.

  Therefore, the pin member 119 of the first gear device 110 (the rotation of the pin member 119 tends to be fast) has a part 119A in the axial direction by the holding hole 164 (the load side holding hole 164A and the anti-load side holding hole 164B). The entire circumference of the side surface of 119B is held at both ends, and is securely held both in the radial direction and in the circumferential direction. As a result, the pin member 119 can be reliably held regardless of the state of eccentric oscillation of the external gear 114, and noise during operation is less likely to occur.

  Further, the second gear device 210 (the number of pin members 219 is large) does not have a holding hole as a through hole that holds the entire circumference of the side surface of the pin member 219. It can be greatly reduced. Further, the pin member 219 of the second gear device 210 is circumferentially regulated by a semicircular pin groove 215 formed in the internal gear main body 217, and the load side and anti-load side cover members 250A and 250B. Since the movement in the radial direction is constrained by being held at both ends by the holding grooves 260 (the load-side holding groove 260A and the anti-load-side holding groove 260B), whether the external gear 214 is in an eccentric oscillation state or not is also determined. Regardless, the pin member 219 can be reliably held.

  In addition, this configuration is particularly suitable for restraining the radial movement of the pin member 219 of the second gear device 210. For example, as in a method of supporting the pin member from the radial inner side by a spear wheel or the like, an "extra member" is used. do not need. That is, when the pin member is supported from the inside in the radial direction by an insertion ring or the like, the diameter of the pin member is different if the reduction ratio is different. Therefore, it is necessary to prepare a dedicated insertion ring for each reduction ratio and constitute a series. However, according to this configuration, the number of parts does not increase.

  In this regard, if the pin member is incorporated so that the innermost inner diameter of the pin member is unified, only one type of insertion ring can be used. However, in this case, the pitch circle diameter of the pin member of the second gear device having the high reduction ratio tends to be smaller than the pitch circle diameter of the pin member of the first gear device having the reduced speed ratio, which is not preferable.

  However, this series also has a favorable tendency in this regard.

  That is, in this series, the holding grooves 160 and 260 (load-side holding grooves 160A and 260A and anti-load-side holding grooves 160B and 260B) of the cover member 150 (load-side cover members 150A and 250A and anti-load-side cover members 150B and 250B). ) Is the center circle diameter d4 (the diameter of the center of the innermost circumference circle d1 and the outermost circumference circle d2) d3. 2 times the distance to the center). In other words, the pitch circle diameter Pcd2 (≈d3) of the pin member 219 of the second gear device 210 to be engaged with the holding groove 260 is equal to the pitch circle of the pin member 119 of the first gear device 110. It is almost synonymous with being larger than the diameter Pcd1 (≈d4) (see also FIGS. 5 and 6).

  With this configuration, the pitch ratio diameter Pcd2 of the pin member 219 of the second gear device 210 having a large reduction ratio and a larger torque and a small diameter can be transmitted, and the pitch circle diameter of the pin member 119 of the first gear device 110 can be reduced. It can be larger than Pcd1. Therefore, the durability of the pin member 219 of the second gear device 210 can be ensured with a sufficient margin, and a very rational tendency can be obtained in terms of strength.

  In this series, as already described, the outer periphery of the pin member 119 of the first gear device 110 has a roller as a sliding acceleration member in order to smoothly slide with the external gear 114. A member 119S is externally fitted. However, on the other hand, the roller member is not externally fitted to the pin member 219 of the second gear device 210. By this differentiation, in particular, it is possible to effectively reduce the sliding resistance of the pin member 119 of the first gear device 110 that tends to increase the sliding between the external gear 114 and the pin member 119, and In the second gear device 210 having a relatively small sliding and a large number of pin members, the manufacturing cost can be reduced (by not providing a roller member). That is, it is possible to achieve both the securing of the effect of reducing the sliding resistance and the cost reduction reasonably. Note that this outer fitting of the roller member may be employed in both the first and second gear devices 110 and 210 (without differentiation) when the effect of reducing sliding resistance is important. If it is important to reduce costs, it may not be used for both.

  In this series, in the first gear device 110 in which the roller member 119S is externally fitted to the outer periphery of the pin member 119, the inner diameter D1 (inner tooth of the forming portion 117A of the load side holding hole 164A of the internal gear main body 117). The distance from the shaft center of the gear 116 to the inner periphery of the forming portion 117A is the innermost diameter D2 of the roller member 119S fitted on the pin member 119 (from the shaft center of the internal gear 116 to the outer periphery of the roller member 119S). The minimum distance) is formed. Accordingly, the external gear 114 can be easily incorporated from the load side regardless of the presence of the roller member 119S. Incidentally, the inner diameter D3 of the forming portion 117B of the anti-load side holding hole 164B of the internal gear main body 117 does not cause the problem of the incorporation of the external gear 114, so it is formed smaller than the innermost diameter D2 of the roller member 119S. The strength of the forming portion 117B is increased. This configuration is particularly advantageous for a gear device in which a roller member is fitted. Thereby, from the side where this relationship is established (the side where the inner diameter of the holding hole forming portion is larger than the innermost diameter of the roller member fitted on the pin member: the load side or the anti-load side) The external gear can be easily incorporated. The inner diameter D3 of the forming portion 117B> the innermost diameter D2 of the roller member 119S> the inner diameter D1 of the forming portion 117A may be set.

  In the above gear device series, a gear device having a center crank type eccentric oscillating speed reduction mechanism having an eccentric body shaft that eccentrically oscillates an external gear at the radial center of the gear device is employed. However, the speed reduction mechanism of the gear device series according to the present invention is not limited to this configuration. For example, a plurality of eccentric body shafts having eccentric bodies for swinging external gears are provided at positions offset from the radial center of the gear device, and the external gears are swung by rotating each eccentric body shaft in synchronization. It can also be applied to an eccentric oscillating gear device called a so-called sorting type. Furthermore, even if it is not an eccentric rocking | fluctuation type gear apparatus, it can apply to the various gear apparatus with which an internal gear is comprised by circular arc tooth profile.

  In the above gear device series, the example in which the difference in the number of teeth between the external teeth of the external gear and the internal teeth of the internal gear is “1” is shown. The number difference may be two or more, for example. In the case of the eccentric oscillating gear device having the above-described configuration, when the difference in the number of teeth is n of 2 or more, the reduction ratio is n / (number of teeth of the internal gear−n). Therefore, if the difference in the number of teeth is kept the same, the greater the reduction ratio, the greater the number of pin members, and the pin members tend to have a smaller diameter. However, the relationship between the reduction gear ratio and the number and diameter of the pin members does not necessarily have this tendency. In the series of gear units according to the present invention, the one having more pin members (regardless of the reduction ratio) and the pin member having a smaller diameter is defined as the second gear unit. As a result, both the first gear device and the second gear device can be manufactured at low cost.

110, 210 ... first and second gear devices 114, 214 ... external gears 116, 216 ... internal gears 117, 217 ... internal gear bodies 119, 219 ... pin members 150, 250 ... cover members 160, 260 ... holding groove

Claims (6)

An internal gear main body, an internal gear having a plurality of pin members arranged on the internal gear main body, the pin member constituting internal teeth, and a cover member connected to the internal gear main body. A series of gear units including a first gear unit and a second gear unit,
The first gear device and the second gear device share the cover member,
The cover member is provided with a holding groove for holding the pin member,
The second gear device has more pin members than the first gear device,
The pin member of the second gear device has a smaller diameter than the pin member of the first gear device,
The internal gear main body of the first gear device has a holding hole that holds a part of the entire circumference of the side surface in the axial direction of the pin member;
The pin member of the first gear device is not held in the holding groove of the cover member, but is held in the holding hole of the internal gear main body,
The internal gear main body of the second gear device is not provided with a holding hole for the pin member, and the pin member of the second gear device is held in the holding groove of the cover member. A series of gear units. In claim 1,
The gear device series, wherein the holding groove of the cover member is formed in an endless ring shape. In claim 1 or 2,
The gear device series, wherein a center circle diameter of the holding groove of the cover member is larger than a center circle diameter of the holding hole of the first gear device. In any one of Claims 1-3,
The cover member includes a first cover member disposed on the axial load side with respect to the internal gear, and a second cover member disposed on the axially opposite load side with respect to the internal gear, A series of gear devices, wherein the holding groove is provided in both the first cover member and the second cover member. In any one of Claims 1-4,
A roller member is fitted on the outer periphery of the pin member,
A series of gear devices, wherein an inner diameter of the holding hole forming portion of the internal gear main body is larger than an innermost diameter of a roller member fitted on the pin member. In claim 5,
The holding hole is formed on both the load side and the anti-load side of the internal gear body,
The inner diameter of one of the holding holes is larger than the innermost diameter of the roller member;
The gear device series, wherein the inner diameter of the other holding hole forming portion is smaller than the innermost diameter of the roller member.

Images