JP2008019962A - Planetary roller transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a planetary roller transmission device capable of canceling thrusting force generated in a loading cam mechanism on a rotating shaft. <P>SOLUTION: The planetary roller transmission device having a rotatable input shaft 9 and a rotatable output shaft 11 comprises a plurality of planetary rollers 33 for freely rolling on the outer periphery of a tapered sun roller 31 provided on the input side, an output ring 41 provided on the output side, on which the planetary rollers 33 are rollingly inscribed, and a shift ring 45 provided movably in a direction parallel to the axis of the input shaft 9, on which tapered parts 33B of the planetary rollers 33 are rollingly inscribed. It has the loading cam mechanism 63 for thrusting the sun roller 31 against the planetary rollers 33 or the loading cam mechanism 21 for thrusting the output ring 41 against the planetary rollers 33. Thrusting force generated in the loading cam mechanism 63 or 21 is received by the rotating shaft 19 of an axil center part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a transmission using a planetary roller mechanism, and more particularly to a planetary roller transmission capable of efficiently transmitting a large torque.

  As a prior example of a transmission using a planetary roller mechanism, there is, for example, Patent Document 1. The configuration described in Patent Document 1 is as shown in FIG.

  That is, an input shaft 207 is rotatably supported by a flange 203 fixed to one end side of a cylindrical housing 201 via a bearing 205, and an output shaft 213 is connected to a flange 209 fixed to the other end side of the housing 201. A bearing 211 is rotatably supported. The input shaft 207 and the output shaft 213 are arranged on the same axis, and the inner end portion of the input shaft 207 is rotatably supported by the output shaft 213 via a bearing 215.

  A tapered sun roller 217 is integrally attached to the inner end side of the input shaft 207 via a key 219, and a plurality of planetary rollers 221 are arranged on the outer periphery of the sun roller 217 so as to be able to roll. The planetary roller 221 is rotatably supported by a cage 225 that is rotatably supported by the input shaft 207 via a bearing 223. The planetary roller 221 is inscribed in a rollable manner on an output ring 227 that is integrally attached to the cup-shaped inner end side of the output shaft 213 via a key.

  That is, the plurality of planetary rollers 221 are held between the sun roller 217 and the output ring 227 so as to be capable of rolling.

A taper portion 221T is formed on one end side of each planetary roller 221. The taper portion 221T is inscribed in a freely rotatable manner on the transmission ring 229. The transmission ring 229 is integrally supported by a moving member 233 that is movably screwed to a screw member 231 that is rotatably supported by the housing 201. Therefore, the transmission ring 229 moves integrally in the axial direction of the input / output shafts 207 and 213 when the moving member 233 is moved by rotating the screw member 231. In the transmission ring 229 and the planetary roller 221, The contact position with the taper portion 221T can be changed.
JP-A-6-280961

  In the conventional configuration as described above, the planetary roller 221 is sandwiched between the sun roller 217 and the output ring 227. Therefore, when the contact pressure between the sun roller 217 and the planetary roller 221 is increased, the planetary roller 221 is increased. Although the contact pressure between the transmission ring 227 and the output ring 227 can be increased, the contact pressure between the transmission ring 229 and the planetary roller 221 cannot be increased.

  Therefore, the contact pressure between the sun roller 217 and the planetary roller 221, the contact pressure between the output ring 227 and the planetary roller 221, and the contact pressure between the transmission ring 229 and the planetary roller 221 are increased to improve transmission efficiency. Has a problem.

  In order to increase the pressing force (contact pressure) against the planetary roller, the patent applicant has applied for a configuration in which the sun roller is pressed against the planetary roller using the thrust force generated in the loading cam mechanism. (Patent application 2005-257750).

  In the configuration in which the sun roller is pressed against the planetary roller using the loading cam mechanism, the reaction force when pressing the sun roller against the planetary roller is received by the housing of the transmission via the bearing. Therefore, in order to receive a large thrust force generated in the loading cam mechanism with the housing, it is necessary to increase the rigidity of the housing, and further improvements are required in order to reduce the size and weight.

  The present invention has been made in view of the above-described problems, and includes an input side having a rotatable input shaft and an output side having a rotatable output shaft, and a tapered shape provided on the input side. A plurality of planetary rollers that can freely roll on the outer periphery of the sun roller, an output ring that is provided on the output side and that inscribes the planetary roller so as to be able to roll, and is movable in a direction parallel to the axis of the input shaft And a planetary roller transmission comprising a transmission ring in which a tapered portion provided in the planetary roller is inscribed so as to be able to roll. A loading cam mechanism for pressing the sun roller against the planetary roller or the output ring is provided in the planetary roller transmission. A loading cam mechanism for pressing against the planetary roller is provided, and a thrust force generated in the loading cam mechanism is applied to the input side or the output side. It is characterized in that it is configured to receive with a rotary shaft provided in the side.

  In the planetary roller transmission, a loading cam mechanism is provided between the output ring and an output-side rotating member to press the output ring against the planetary roller. The generated thrust force is received by a rotating shaft provided on the input side.

  Further, in the planetary roller transmission, a loading cam mechanism is provided between the sun roller and an input-side rotating member to press the sun roller against the planet roller, and is generated in the loading cam mechanism. The thrust force is received by a rotating shaft provided on the output side.

  A plurality of planetary rollers, each comprising an input side having a rotatable input shaft and an output side having a rotatable output shaft, the outer periphery of the tapered sun roller provided on the input side being rotatable; An output ring that is provided on the output side and in which the planetary roller is inscribed in a freely rolling manner, and is movable in a direction parallel to the axis of the input shaft, and is capable of rolling a tapered portion provided in the planetary roller. A planetary roller transmission provided with a transmission ring inscribed therein, comprising: a loading cam mechanism for pressing the sun roller against the planetary roller; and a loading cam mechanism for pressing the output ring against the planetary roller, The structure is characterized in that a thrust force generated in both loading cam mechanisms is received by a rotary shaft provided in the shaft center portion.

  According to the present invention, forces in opposite directions in the thrust direction generated in the loading cam mechanism are received at both ends of one rotating shaft, and are canceled out to each other, so that they can be transmitted to the housing of the transmission. However, the problem as described above can be solved.

  Referring to FIG. 1, a planetary roller transmission 1 according to an embodiment of the present invention includes a hollow housing 3, and a flange member 5 is attached to an opening on one end side of the housing 3. . An input shaft 9 is rotatably supported at the center of the flange member 5 via a bearing 7. On the other end side of the housing 3, an output shaft 11 facing the input shaft 9 is rotatably supported via a bearing 13. Note that the inside of the housing 3 is sealed by seal members 15 arranged in each part.

  An axial support hole 17 is formed in the axial center of the inner end portion of the input shaft 9, and one end of an input-side rotary shaft 19 provided in the axial center portion is rotatable in the support hole 17. It is inserted and supported so as to be movable in the axial direction. The other end of the rotating shaft 19 is rotatably supported by a loading cam 23 in a loading cam mechanism 21 via a bearing 25.

  More specifically, a cup-shaped large-diameter portion 27 that is rotatably supported by the bearing 13 is provided at the inner end portion of the output shaft 11, and the loading cam is disposed on the inner surface of the large-diameter portion 27. 23 is integrally attached by a fixture such as a bolt. An appropriate bearing 25 such as a thrust bearing is interposed between the loading member 23 and the flange member 29 in which the other end portion of the rotary shaft 19 is integrally screwed and fixed.

  In order to shift the rotation of the input shaft 9 and transmit it to the output shaft 11, a taper-shaped sun roller (input roller) 31 rotated by the input shaft 9 is rotatable on the rotating shaft 19 in the axial direction. It is supported so as to be movable. The outer peripheral surface of the sun roller 31 is formed in a tapered shape having a small diameter on the output shaft 11 side, and a plurality of planetary rollers 33 are arranged on the tapered outer peripheral surface of the sun roller 31 so as to be able to roll (revolve freely). It is.

  The movement of the sun roller 31 in the direction of the input shaft 9 is restricted by a disk-shaped stopper 19S provided on the rotating shaft 19. Further, an elastic member 32 such as a coil spring is mounted between the sun roller 31 and the loading cam 23.

  The planetary rollers 33 are arranged at equal intervals in a virtual taper surface having a small diameter on the output shaft 11 side and a large diameter on the input shaft 9 side, and the first tapered portion 33A on the output shaft 11 side and the input shaft 9 side are arranged. The second taper portion 33B is provided. The first taper portion 33A and the second taper portion 33B are formed such that both end portions have a small diameter from the vicinity of the central portion in the longitudinal direction of the planetary roller 33. Then, both end portions of each planetary roller 33 are rotatably supported by a tapered cage 35.

  The cage 35 includes a large-diameter ring portion 35A that is rotatably supported on the outer periphery of a large-diameter portion 37 formed at the inner end portion of the input shaft 9 via a bearing, and an inner surface of the loading cam 23. The cylindrical portion 39 is integrally formed with a small-diameter ring portion 35B supported via a bearing. Both end portions of each planetary roller 33 are rotatably supported by the large diameter ring portion 35A and the small diameter ring portion 35B.

  The sun roller 31 is in contact with the vicinity of the large diameter portion (base side) of the first taper portion 33A of the plurality of planetary rollers 33, and the outside of the vicinity of the small diameter portion (tip end side) of the first taper portion 33A. The output ring 41 is in contact with a relatively rollable state. The output ring 41 is supported by the loading cam 23 so as to be rotatable and movable in the axial direction, and the planetary roller 33 is inscribed inside the output ring 41 so as to freely roll (revolve).

  Between the output ring 41 and the loading cam 23, the loading cam mechanism 21 for increasing the pressing force (pressing force) of the output ring 41 against the planetary roller 33 is interposed. More specifically, a plurality of cam grooves 23C and 41C having a V-shaped cam surface formed in the radial direction (radial direction) are opposed to the opposed surfaces where the loading cam 23 and the output ring 41 are opposed to each other. A force transmission member 43 such as a ball or a roller is interposed in the opposed cam grooves 23C and 41C.

  When the load is applied to the output shaft 11 and a slight phase difference is generated between the output ring 41 and the loading cam 23, the loading cam mechanism 21 has the cam surfaces inclined by the cam grooves 23C and 41C. The force transmission member 43 is pinched, and a large thrust force is generated that presses the output ring 41 against the planetary roller 33. The magnitude of the pressing force generated at this time can be set to a pressing force corresponding to the load acting on the output shaft 11 by setting the inclination angle of the cam surface in the cam grooves 23C and 41C to a predetermined angle in advance. Is.

  As already understood, when a load is applied to the output shaft 11, the pressing force of the output ring 41 against the planetary roller 33 becomes larger, and the transmission efficiency between the planetary roller 33 and the output ring 41 is improved. It is intended.

  A bus bar on the outer side of the second tapered portion 33B of the planetary roller 33 is parallel to the axis of the rotary shaft 19, and the inner surface of the transmission ring 45 is in contact with the bus bar portion. The transmission ring 45 is guided by a plurality of guide members 47 such as bolts that fasten and fix the flange member 5 to the housing 3, and is provided so as to be movable in a direction parallel to the axis of the rotary shaft 19. In order to move the transmission ring 45, a screw member 49 parallel to the guide member 47 is rotatably provided in the housing 3, and the transmission ring 45 is movable to the screw member 49. It is screwed.

  Therefore, when the shift member such as a handle (not shown) provided outside the housing 3 is operated to rotate the screw member 49, the shift ring 45 is guided and moved by the guide member 47, and the planetary roller is moved. The contact position of the transmission ring 45 with respect to the second taper portion 33B at 33 can be changed.

  In order to transmit the rotation of the input shaft 9 to the sun roller 31 and press the sun roller 31 against the planetary roller 33, a rotational force transmission mechanism 51 is provided between the input shaft 9 and the sun roller 31. More specifically, a plurality of portions of the large-diameter portion 37 of the input shaft 9 are slidably engaged with a plurality of axial engagement grooves 31G provided on the outer peripheral surface of the sun roller 31. A protruding portion 37P is provided. That is, the engagement groove 31G and the protruding portion 37P constitute a kind of meshing clutch that always maintains the engaged state. Therefore, the rotation of the input shaft 9 can be transmitted to the sun roller 31.

  In order to press the sun roller 31 against the planetary roller 33 during the rotation of the input shaft 9, a plurality of long grooves 53 in the radial direction are formed on the facing surface of the input shaft 9 facing the sun roller 31. Inside, a moving body 55 such as a ball or a roller is movably housed. A cam surface 57 that is in contact with the moving body 55 and is inclined so that the outer diameter side approaches the input shaft 9 side is formed on the facing surface where the sun roller 31 faces the input shaft 9. is there.

  As apparent from the above configuration, the sun roller 31 is in contact with a substantially intermediate portion in the longitudinal direction of the planetary roller 33 so as to press the planetary roller 33 outward from the inside. The output ring 41 and the transmission ring 45 are in contact with the end side of the planetary roller 33 so as to restrict the outward movement of the planetary roller 33. In other words, the force by which the sun roller 31 presses the vicinity of the center of the planetary roller 33 outward and the force by which the output ring 41 and the transmission ring 45 press both ends of the planetary roller 33 inward are balanced. There is something.

  Therefore, when the contact pressure between the sun roller 31 and the planetary roller 33 is increased, the contact pressure between the output ring 41, the transmission ring 45 and the planetary roller 33 is increased, and the contact pressure is increased to improve the transmission efficiency. It can be planned.

  In the configuration as described above, when the input shaft 9 is rotated, the sun roller 31 is integrally rotated via the moving body 55 and the like. Therefore, the planetary roller 33 that is in rolling contact with the outer periphery of the sun roller 31 is rotated (rotated) by the sun roller 31. Since the planetary roller 33 is inscribed in a freely rotating manner on the transmission ring 45 that is stationary in the rotational direction, the planetary roller 33 rolls (revolves) along the transmission ring 45.

  Here, when the transmission ring 45 is in contact with the neutral position of the second tapered portion 33B of the planetary roller 33, the output shaft 11 is in a stopped state and the output is zero. When the transmission ring 45 is moved rightward in FIG. 1 (the state shown in FIG. 1) and the contact position of the transmission ring 45 is moved to the small diameter side of the second taper portion 33B of the planetary roller 33, the output shaft 11 Is gradually increased. When the transmission ring 45 is moved in the left direction from the neutral position, the output shaft 11 is reversely rotated.

  As described above, when the input shaft 9 is rotated and gradually increases in speed, the moving body 55 provided in the large-diameter portion 37 of the input shaft 11 is gradually moved outward in the radial direction by centrifugal force. When the moving body 55 is moved outward along the long groove 53, the sun roller 31 is gradually pressed against the planetary roller 33 by the action of the cam surface 57, and the contact pressure gradually increases.

  When the input shaft 9 rotates at a low speed and the centrifugal force acting on the moving body 55 becomes small, the moving body 55 is moved inward by the biasing force of the elastic member 32 and the action of the cam surface 57. Therefore, the pressing force that presses the sun roller 31 is reduced, slipping occurs between the sun roller 31 and the planetary roller 33, and transmission of force to the output shaft 11 is interrupted. That is, a kind of clutch function is exhibited. Therefore, regardless of the position of the transmission ring 45, the clutch can be disengaged by lowering the rotation speed of the input shaft 9, and safety can be improved.

  Incidentally, as described above, when the input shaft 9 is rotated to rotate the sun roller 31 integrally and the output ring 41 is rotated via the planetary roller 33, the output shaft 11 is rotated integrally via the loading cam mechanism 21. The When a load is applied to the output shaft 11, the loading cam 23 and the output ring 41 in the loading cam mechanism 21 are slightly displaced in the rotational direction (phase difference).

  As described above, when a slight phase difference occurs between the loading cam 23 and the output ring 41, the cam grooves 23 </ b> C and 41 </ b> C included in the respective cam grooves 23 </ b> C and 41 </ b> C cause a wedge action due to the force transmission member 43 being pinched more strongly. The output ring 41 is strongly pressed against the planetary roller 33. When the pressing force of the output ring 41 against the planetary roller 33 increases and the contact pressure gradually increases, the contact pressure between the sun roller 31 and the planetary roller 33 that supports the planetary roller 33 from the inside also increases.

  Furthermore, the contact pressure between the second tapered portion 33B of the planetary roller 33 and the transmission ring 45, which tends to be pressed outward with the contact position between the sun roller 31 and the planetary roller 33 as a fulcrum, also increases. Therefore, the contact pressure according to the load of the output shaft 11 can be secured, and a large load can be transmitted.

  As described above, the force that presses the output ring 41 toward the planetary roller 33 by the action of the loading cam mechanism 21 is transmitted to the sun roller 31 through the planetary roller 33. The sun roller 31 abuts against a stopper 19S provided on the rotating shaft 19, and movement in the right direction is restricted. That is, a force in the right direction in FIG. 1 acts on the stopper 19S.

  On the other hand, the reaction force of the force pressing the output ring 41 in the direction of the planetary roller 33 is received by the loading cam 23, and the loading cam 23 tends to move to the left in FIG. The force acting on the loading cam 23 is transmitted to the rotary shaft 19 via the bearing 25 and the flange member 29. That is, in FIG. 1, a rightward force acts on the right end portion side of the rotating shaft 19, and a leftward force acts on the left end portion side of the rotating shaft 19.

  Therefore, the force in the left-right direction (thrust direction) generated in the loading cam mechanism 21 is received by the rotating shaft 19 and is canceled by the rotating shaft 19. Therefore, since the lateral force described above is not transmitted to the housing 3, the housing 3 does not need to have a thick rigid structure, for example, and the overall structure can be reduced in size and weight. The problem can be solved.

  FIG. 2 shows a second embodiment, and the same reference numerals are given to components having the same functions as those described above, and redundant description is omitted.

  In this embodiment, an output gear 59 is provided on the outer peripheral surface of the loading cam 23, and a gear 61 provided on the output shaft 11 is engaged with the output gear 59. In this configuration, the input shaft 9 and the output shaft 11 can be removed from the same axis, and the degree of freedom of the arrangement position of the output shaft 11 with respect to the input shaft 9 is improved.

  FIG. 3 shows a third embodiment, and the same reference numerals are given to components having the same mechanism as the configuration of the above-described embodiment, and redundant description is omitted.

  In the third embodiment, the sun roller 31 is divided into a first roller 31A having a tapered portion on the planetary roller 33 side and a second roller 31B on the rotational force transmission mechanism 51 side, and the first roller 31A is divided. The loading cam mechanism 63 having the same configuration as the loading cam mechanism 21 is provided between the first roller 31B and the second roller 31B. That is, cam grooves 31C similar to the cam grooves 23C and 41C are provided on the opposing surfaces of the first and second rollers 31A and 31B, respectively, and the force transmission member 43 is provided in the opposing cam grooves 31C. A force transmission member 65 similar to the above is interposed.

  In the above configuration, the first roller 31 </ b> A is strongly pressed against the planetary roller 33 by the action of the one loading cam mechanism 63, and the output ring 41 is strongly pressed against the planetary roller 33 by the action of the other loading cam mechanism 21. . That is, since the loading cam mechanism 63 is provided on the input side and the loading cam mechanism 21 is provided on the output side, the contact pressure between the sun roller 31 and the planetary roller 33, the output ring 41, the transmission ring 45, and the planetary roller are provided. Thus, the contact pressure between the first and second members 33 can be increased, and the output efficiency can be further improved.

  In addition, the reaction force of the thrust force generated in the loading cam mechanisms 21 and 63 is received at both ends of the rotating shaft 19, and the same effect as described above can be obtained.

  In the embodiment shown in FIG. 3, when the loading cam mechanism 21 is omitted, the loading cam 23 and the output ring 41 may be integrated. It is possible to omit the output shaft 11 and the rotating shaft 19 and integrate them. In this case, the rotating shaft 19 belongs to the output side.

  As can be understood, the loading cam mechanism can be implemented as a configuration including a loading cam mechanism on at least one of the input side and the output side.

It is a section explanatory view of the planetary roller transmission concerning a 1st embodiment of the present invention. It is a section explanatory view of the planetary roller transmission concerning a 2nd embodiment of the present invention. It is a section explanatory view of a planetary roller transmission concerning a 3rd embodiment of the present invention. It is sectional explanatory drawing which shows the conventional structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Planetary roller transmission 3 Housing 9 Input shaft 11 Output shaft 19 Rotating shaft 19S Stopper 21, 63 Loading cam mechanism 23 Loading cam 23C, 31C, 41C Cam groove 25 Bearing 31 Sun roller 33 Planetary roller 33A 1st taper part 33B 2nd taper Part 35 Cage 37 Large diameter part 41 Output ring 43, 65 Force transmission member 45 Transmission ring 51 Rotational force transmission mechanism 53 Long groove 55 Moving body 57 Cam surface

Claims (4)

  A plurality of planetary rollers having an input side having a rotatable input shaft and an output side having a rotatable output shaft, the outer periphery of a tapered sun roller provided on the input side being freely rotatable; and the output An output ring which is provided on the side and in which the planetary roller is inscribed in a rollable manner, and is movable in a direction parallel to the axis of the input shaft, and a tapered portion provided in the planetary roller is provided in a rollable manner. A planetary roller transmission comprising a contact ring, and a loading cam mechanism for pressing the sun roller against the planet roller or a loading cam mechanism for pressing the output ring against the planet roller. And a structure in which thrust force generated in the loading cam mechanism is received by a rotating shaft provided on the input side or output side. Planetary roller transmission device according to.   2. The planetary roller transmission according to claim 1, wherein a loading cam mechanism is provided between the output ring and an output-side rotating member to press the output ring against the planetary roller. A planetary roller transmission characterized in that a thrust force generated in a cam mechanism is received by a rotating shaft provided on an input side.   2. The planetary roller transmission according to claim 1, wherein a loading cam mechanism is provided between the sun roller and an input side rotating member to press the sun roller against the planet roller. A planetary roller transmission having a structure in which the thrust force generated in the shaft is received by a rotating shaft provided on the output side.   A plurality of planetary rollers having an input side having a rotatable input shaft and an output side having a rotatable output shaft, the outer periphery of a tapered sun roller provided on the input side being freely rotatable; and the output An output ring which is provided on the side and in which the planetary roller is inscribed in a rollable manner, and is movable in a direction parallel to the axis of the input shaft, and a tapered portion provided in the planetary roller is provided in a rollable manner. A planetary roller transmission comprising a contact ring, and a loading cam mechanism for pressing the sun roller against the planet roller and a loading cam mechanism for pressing the output ring against the planet roller. A planetary roller transmission having a structure in which a thrust force generated in a cam mechanism is received by a rotating shaft provided in an axial center portion.

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