JP4948968B2 - Planetary roller type transmission - Google Patents

Description

  The present invention relates to a planetary roller transmission, and more particularly to a planetary roller transmission for automobiles or industrial machines.

  A traction drive is a kind of friction transmission device, and power is transmitted through an oil film formed between two surfaces having a smooth surface. Therefore, it has a feature that it can be operated with lower vibration and lower noise than a gear transmission.

  A typical traction drive having a constant gear ratio is a planetary roller transmission as shown in FIG. This device includes a fixed wheel 1 and a sun roller 2 that are arranged so that their axial centers coincide with each other, a plurality of planetary rollers 3 that are arranged in a space formed between the fixed wheel 1 and the sun roller 2, and It is comprised with the carrier 4 which hold | maintains the planetary roller 3 rotatably. The fixed ring 1 is fixed to the inner surface of the housing 5. The shaft portion 6 of the sun roller 2 and the carrier 4 is rotatably supported by the housing 5 via bearings 7 and 8. The carrier 4 includes a carrier main body 10 having a flange 9 integral with the shaft portion 6, planetary roller support shaft press-fitting holes 11 formed at equal circumferential positions on the flange 9 of the carrier main body 10, and the holes 11 and a planetary roller support shaft 12 press-fitted into 11. With respect to the planetary roller support shaft 12, the planetary rollers 3 are arranged at equal intervals in the circumferential direction via planetary roller support bearings 13 and are rotatably supported. As described above, the fixed wheel 1 is fixed to the housing 5 so that its rotation is restricted, so that power is transmitted between the sun roller 2 and the carrier 4 (see, for example, Patent Document 1).

  In the traction drive, it is necessary to apply a normal force necessary for power transmission to each contact portion. If this normal force is insufficient, excessive sliding occurs at the contact portion, resulting in damage such as seizure. In the planetary roller transmission shown in FIG. 9, the normal force required for each contact is generated by assembling by a shrink fit method. The shrink-fitting method is a method of assembling a planetary roller type transmission by heating and expanding the fixed ring 1 to be larger than the interference allowance set by the inner diameter size of the fixed wheel 1 and the outer diameter size of the sun roller 2 and the planetary roller 3. Yes, after assembly, the fixed ring 1 contracts due to cooling, and as a result, a constant normal force acts on each contact portion. The normal force generation method by shrink fitting has the advantage that the normal force is obtained only by the power transmission member, so that the number of parts is small and the structure is simple.

  In the pressurization method in which a constant normal force is applied to the contact portion like the shrink fitting method, the normal force is set according to the maximum load. Therefore, the normal force becomes excessive at low loads, and the transmission efficiency and rolling fatigue life are deteriorated. In order to minimize such a decrease in transmission efficiency and fatigue life, it is effective to provide a pressurizing mechanism that can vary the normal force of the contact portion in accordance with the load torque. By providing the variable pressurization mechanism, it is possible to suppress the generation of excessive normal force on the contact surface, and it is possible to improve transmission efficiency at low load torque and extend the life of the transmission.

  An example (Patent Document 2) of a planetary roller transmission having a variable pressure mechanism is shown in FIG. In this planetary roller transmission, the outer ring 21 and the two sun rollers 22A and 22B are coaxially arranged, and a plurality of planetary rollers 23 are provided by the carrier 24 between the outer ring 21 and the two sun rollers 22A and 22B. It is arranged to rotate and revolve at equal intervals in the circumferential direction. In contact between the outer ring 21 and the planetary roller 23 and between the planetary roller 23 and the sun rollers 22A and 22B, each member is formed to have a certain contact angle with respect to the input / output axis. Further, the first sun roller 22 </ b> A is provided to be rotatable with respect to the sun shaft 25.

  Power is transmitted to the sun shaft 25 from the input shaft 26 through power transmission means such as a key or a spline. The power between the first sun roller 22A and the sun shaft 25 is transmitted via the cam ring 27. The power between the cam ring 27 and the sun shaft 25 is transmitted by a key or a spline. The cam ring 27 and the first sun roller 22A are formed with a cam surface facing each other, and a rolling element (steel ball) 28 is provided between the cam surfaces to constitute a torque cam 29. The power between the cam ring 27 and the first sun roller 22A is transmitted by the torque cam 29. During power transmission, the torque cam 29 causes an axial force corresponding to the transmission torque to act on the first sun roller 22A, and a normal force acts between the first sun roller 22A and the planetary roller 23.

  The second sun roller 22B is provided so that its movement in the axial direction is restricted with respect to the sun shaft 25 and power can be transmitted by a key or a spline. Since the two sun rollers 22A and 22B are structured such that the movement is restricted in the axial direction, the same normal force acting between the first sun roller 22A and the planetary roller 23 is the same as the second sun roller 22B and the planetary roller. 23 also works.

  The carrier 24 has a carrier body 32 in which an output shaft 30 and a flange 31 are integrally formed, and the rotation support shaft 34 of the planetary roller 23 is provided in a carrier slot 33 provided at equal intervals in the circumferential direction of the flange 31. In addition, as described above, the planetary roller 23 can rotate and can revolve around the sun axis 25.

  In the planetary roller type transmission shown in FIG. 10, each contact is made only by the axial force generated by a torque cam 29 composed of a cam surface provided opposite to the sun roller 22A and the cam ring 27 and a rolling element 28 such as a steel ball. The normal force acting on the part is determined. Therefore, under a low load condition where the torque transmitted between the sun roller 22A and the cam ring 27 is small, a surface pressure sufficient to obtain a sufficient traction coefficient is not generated, and as a result, excessive slip (gross slip) is likely to occur. Due to such a phenomenon that a relatively large slip occurs until no gloss slip occurs, a malfunction such as wear occurs and the function is impaired.

In order to solve such problems, an axial movement restricting means for restricting the axial movement of the sun roller and the cam ring is provided on the sun shaft, and the sun roller is disposed in the axial direction between the sun roller and the axial movement restricting means. The thing which provided the elastic member to pressurize is proposed (patent document 3). In other words, the elastic member causes an axial pressure force that biases the second sun roller toward the first sun roller, and an axial force corresponding to the transmission torque is generated when power is transmitted by the torque cam. I tried to do it.
JP 2002-39383 A JP-A-6-185532

  In the variable pressure planetary roller transmission described in Patent Document 2 and Patent Document 3, the outer ring is restrained so as not to rotate with respect to the housing, and power is transmitted between the sun shaft and the carrier. In this case, in order to equalize the normal force acting between the two sun rollers and the planetary roller, it is necessary to support the sun shaft so that it can move freely in the axial direction. However, since the joint is slidable in the axial direction and connected to one of the input / output shafts, there arises a problem that the size of the apparatus increases in the axial direction. In addition, when the rotation of the carrier that supports the planetary rollers at equal intervals in the circumferential direction is used for power transmission, the planetary rollers will revolve, which increases the loss of stirring of the lubricating oil, etc. Not suitable.

  In view of the above problems, the present invention provides a planetary roller transmission that can cope with high-speed rotation and can be reduced in axial length.

In the planetary roller transmission of the present invention, a sun shaft, a low speed shaft, a pair of first and second sun rollers having a rolling surface on the outer peripheral surface, and an outer ring having a rolling surface on the inner peripheral surface are coaxial. A plurality of planetary rollers are arranged in the space between the first and second sun rollers and the outer ring so as not to revolve at equal intervals in the circumferential direction, and the rolling surfaces of the first and second sun rollers are the axis of the sun axis. A power is transmitted between the second sun roller and the sun shaft by means of rotating the second sun roller and the sun shaft integrally with the planetary roller rolling surface at a certain contact angle with respect to the center. A cam ring that rotates integrally with the sun shaft is provided coaxially with the sun shaft, and a cam surface is formed opposite to the first sun roller and the cam ring, and is provided by direct engagement between the cam surfaces or between the cam surfaces. The first sunro through the rolling element And power is transmitted between the cam ring, the planetary roller type transmission axial movement of the first sun roller and the cam ring is restricted by an axial movement regulating means provided on the sun shaft, said plurality of planetary rollers, revolve together but are rotational and axial movement can be a bearing supported in a state of being restricted, the sun shaft is bearing supported so as axial movement is restrained, and a Utaringu the axial direction with respect to the slow axis The power transmission means is connected via a power transmission means so as to be movable , and the power transmission means is formed by a fitting structure constituted by a notch portion extending in the axial direction and an axial protrusion portion fitted to the cutout portion. The structure is arranged on the outer diameter side of the outer ring, and the end of the sun shaft is inserted into the hole provided in the low speed shaft up to the position corresponding to the pivot of the low speed shaft, and the end of the sun shaft is inserted into the low speed shaft In the hole It is obtained by the bearing support to have.

  According to the present invention, since the revolution of the planetary roller can be eliminated, the stirring resistance of the lubricating oil can be reduced. Also, since the planetary roller can be moved in the axial direction, the sun shaft is supported so that it can freely move in the axial direction in order to equalize the normal force acting between the two sun rollers and the planetary roller. This eliminates the need for connecting one of the input / output shafts with a joint that can slide in the axial direction.

The first between the sun roller and the cam ring or one at least one of between the cam ring and the axial movement restricting means, yet preferably an elastic member that generates a load in the axial direction.

  The planetary roller and the outer ring are in contact with each other at two points forming a predetermined contact angle with the sun axis, or the planetary roller and the outer ring are in contact at one point by the crowning convex part and the crowning concave part. In other words, the axial relative displacement between the planetary roller and the outer ring can be restricted.

  In the present invention, by eliminating the carrier revolution (planetary roller revolution), it is possible to reduce the stirring resistance and to cope with the high speed rotation. Further, it is not necessary to connect one of the input / output shafts by a joint portion that can slide in the axial direction, and the axial length can be reduced.

  Since the fitting structure which is a power transmission means between the low speed shaft and the outer ring is arranged on the outer diameter side of the outer ring, the enlargement in the axial direction due to the provision of the fitting structure can be prevented. Further, the skew moment of the outer ring can be reduced, which is advantageous for smooth rotation.

  By providing an elastic member that generates an axial load, it is possible to improve power transmission performance at a low load, to suppress excessive slip, and to prevent deterioration in function due to wear or the like. Further, if the end of the sun shaft is inserted into the hole on the low speed shaft and the end of the sun shaft is supported by the hole in the hole on the low speed shaft, the axial size can be further reduced.

  Also, the planetary roller and the outer ring are in contact with each other at two points forming a predetermined contact angle with the sun axis, or the planetary roller and the outer ring are in contact at one point by the crowning convex part and the crowning concave part. By doing so, it is possible to restrict the axial relative displacement between the planetary roller and the outer ring. As a result, power transmission between the planetary roller and the outer ring is stabilized, and a high-quality planetary roller transmission is obtained.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  FIG. 1 shows a planetary roller transmission according to the present invention. This planetary roller transmission has a sun shaft 42 as an input shaft (high speed shaft), a low speed shaft 45 as an output shaft, and a rolling surface on the outer peripheral surface. And a pair of first and second sun rollers 43A and 43B and an outer ring 41 having a rolling surface on the inner peripheral surface, and these are arranged coaxially. A plurality of planetary rollers 44 are arranged in the space between the sun rollers 43A and 43B and the outer ring 41 so as not to revolve at equal intervals in the circumferential direction.

  The sun rollers 43A and 43B, the outer ring 41, the planetary roller 44, and the like are housed in a casing (housing) 46. The casing 46 includes a case main body 47 and a lid body 48 that closes the opening of the case main body 47. The case main body 47 includes a large-diameter short cylindrical portion 47a, a large side wall 47b on the side opposite to the lid of the short cylindrical portion 47a, and a small diameter short cylindrical portion 47c connected to the side wall 47b and projecting toward the counter-lid body. And a small side wall 47d connected to the short cylinder portion 47c.

  The lid body 48 is provided with an insertion hole 48 a, and the sun shaft 42 is rotatably inserted into the insertion hole 48 a via a bearing 49. In this case, the bearing 49 is disposed on the case inner side of the insertion hole 48a, and the seal member 50 is fitted on the case outer side of the insertion hole 48a.

  The sun shaft 42 is integrally formed with a second sun roller 43B on the inner side of the case, and an insertion hole 48a is provided with a stepped portion 51 in the vicinity of the sun roller 43B, and a retaining ring 52 attached to the insertion hole 48a, and a stepped portion. A bearing 49 is disposed between the first bearing 51 and the bearing 51. That is, the sun shaft 42 has a large-diameter portion 53 constituting the sun roller 43 </ b> B, an insertion hole corresponding portion 54 disposed closer to the lid body 48 than the large-diameter portion 53, and the large-diameter portion 53. And a protrusion 55 disposed on the side opposite to the cover. A rolling surface 58 formed of a concave curved surface that contacts the planetary roller 44 at a predetermined contact angle β is formed on the outer diameter surface of the large-diameter portion 53, thereby forming the sun roller 43 </ b> B. In addition, a protruding shaft portion 56 is connected to the end surface of the protruding portion 55, and a spline portion 57 is provided on the protruding shaft portion 56 side of the protruding portion 55.

  An insertion hole 59 is provided in the small side wall 47 d of the case body 47, and the low speed shaft 45 is inserted through the insertion hole 59. That is, as shown in FIGS. 3A and 3B, the low-speed shaft 45 includes a shaft portion 60, a boss portion 61 provided continuously with an end portion of the shaft portion 60, and a countershaft portion of the boss portion 61. Projecting piece portions 62 and 62 projecting in the opposite direction 180 degrees projecting from the outer diameter surface on the side in the outer diameter direction. In this case, the protruding piece portions 62, 62 are a main body portion 62a that protrudes in a direction orthogonal to the axis of the low speed shaft 45 (that is, the axis O of the speed reducer), and the outer diameter end of the main body portion 62a. The extending portion 62b extends to the opposite boss side in parallel with the axis of the low-speed shaft 45.

  The boss 61 is provided with a hole 63. The hole 63 includes a large-diameter portion 63a on the opening side, a tapered portion 63b continuously connected to the large-diameter portion 63a and having a diameter reduced toward the shaft portion 60, and a central portion connected to the tapered portion 63b. It consists of a diameter part 63c and a small diameter part 63d connected to the medium diameter part 63c.

  As shown in FIG. 1, the boss portion 61 is rotatably fitted in a recess 65 (a recess formed by the short tube portion 47 c and the small side wall 47 d) of the case body 47 via a bearing 66. Then, the protruding shaft portion 56 of the sun shaft 42 is fitted into the middle diameter portion 63 c of the hole portion 63 of the boss portion 61, and the protruding shaft portion 56 is pivotally supported via the bearing 66. As described above, the sun shaft 42 is rotatably supported by the bearing 49 provided in the lid 48 of the casing 46 and the bearing 66 disposed in the hole 63 of the low speed shaft 45, and moves in the axial direction. Is regulated (restrained). A sealing material 50 is fitted in the through hole 59 through which the low speed shaft 45 of the small side wall 47d of the casing 46 is inserted.

  As shown in FIG. 4, the first sun roller 43A is a ring body having a center hole 70 having a small diameter portion 70a and a large diameter portion 70b, and contacts the planetary roller 44 at a predetermined contact angle β on the outer diameter surface. A rolling surface 71 made of a concave curved surface is formed. Further, when the inner diameter dimension of the small diameter part 70a is set larger than the outer diameter dimension of the projecting part 55 of the sun shaft 42 and only the sun roller 43A is viewed, the outer part is rotatably fitted to the projecting part 55.

  For this reason, as shown in FIG. 1, the planetary roller 44 is formed with rolling surfaces 72 and 73 having convex curved surfaces for contacting the sun rollers 43A and 43B at a predetermined contact angle β on the outer diameter surface thereof. A support shaft 74 protruding from the body 48 side is rotatably fitted via a bearing 75. That is, the support shaft 74 moves from the base 76 attached to the inner surface of the lid 48 to the inside of the case at a predetermined pitch (120 ° pitch in the example) along the circumferential direction (that is, this deceleration). It projects parallel to the machine axis O). The support shaft 74 includes a base portion 74a that fits into the support hole of the base 76, a large diameter portion 74b that contacts the base 76, and a support portion 74c that is inserted into the planetary roller 44 and onto which the bearing 75 is fitted. Is provided. A retaining ring 77 is fitted to the tip of the support portion 74c.

  The outer ring 41 is in pressure contact with the planetary roller 44 at a contact angle of α with respect to the axis of the sun shaft 42. For this reason, the inner ring surface of the outer ring 41 is provided with rolling surfaces 78 and 79 which are concave curved surfaces for contacting the planetary rollers 44 at a contact angle α with the convex curved surfaces 72 and 73 of the planetary rollers 44. In this case, an outer surface 80 parallel to the axial center is provided between the convex curved surfaces 72 and 73 of the planetary roller 44, and a circumferential groove 81 is provided between the concave curved surfaces 78 and 79 of the outer ring 41. Yes.

  The outer ring 41 is connected to the low-speed shaft 45 by power transmission means 82 that can move in the axial direction. In this case, the power transmission means 82 includes an axial cutout 84 formed on the outer diameter surface 83 of the outer ring 41 and a protrusion 85 fitted into the cutout 84. As shown in FIG. 2, the notches 84 are provided at two positions 180 degrees opposite to each other with respect to the axial center, and the extending portions 62 b of the low speed shaft 45 are fitted into the notches 84. For this reason, the extending | stretching part 62b comprises the said protrusion part 85. FIG.

  The power between the first sun roller 43A and the sun shaft 42 is transmitted through the cam ring 87 as shown in FIGS. A cam surface is formed on the sun roller 43A and the cam ring 87 so as to face each other, and a rolling element (steel ball or the like) 88 is provided between the cam surfaces to constitute a torque cam 89. The cam ring 87 has a center hole 90 having a small diameter portion 90a and a large diameter portion 90b, and a spline portion 91 that fits the spline portion 57 of the projecting portion 55 of the sun shaft 42 is provided on the inner diameter surface of the small diameter portion 90a. It is done. Thereby, the power between the cam ring 87 and the sun shaft 42 is transmitted.

  A retaining ring 92a as an axial movement restricting means 92 is fitted to the spline portion 57 of the projecting portion 55 of the sun shaft 42, and the cam ring 87 is prevented from coming off on the projecting shaft portion 56 side. Further, the large-diameter portion 90b of the cam ring 87 and the large-diameter portion 70b of the sun roller 43A face each other, and an annular space 93 is formed on the outer peripheral side of the projecting portion 55 of the sun shaft 42. Coil springs are inserted. That is, the elastic member 94 applies an axial pressure force that urges the sun roller 43A toward the sun roller 43B. With such a configuration, when power is transmitted by the torque cam 89 formed by the cam surfaces 95a and 95b formed on the sun roller 43A and the cam ring 87 and the rolling elements 88, an axial force corresponding to the transmitted torque is generated. .

  The mechanism of the torque cam 89 is shown in FIGS. 5 (A), 5 (B), and 6. FIG. As shown in FIG. 5A, the sun roller 43A and the cam ring 87 are formed with 95a and 95b so as to face each other. Furthermore, between these cam surfaces 95a and 95b, as described above, rolling elements 88 such as steel balls are provided. When torque is transmitted to the torque cam 89, as apparent from FIG. 6, the rolling elements 88 move in the circumferential direction along the cam surfaces 95a and 95b. Then, as shown in FIG. 5 (B), a circumferential force Ft acting by the transmission torque and an axial force Fa determined by the cam surface angle are generated.

  In the planetary roller transmission configured as described above, when the sun shaft 42 rotates, the first sun roller 43B integrated with the sun shaft 42 rotates, and an axial force Fa acts on the sun roller 43A from the torque cam 89. The sun roller 43A also rotates together. Each planetary roller 44 rotates around the support shaft 74 by the rotation of the sun rollers 43A and 43B. That is, each planetary roller 44 rotates without revolving. As the planetary rollers 44 rotate, the outer ring 41 rotates around the center of the sun. If the outer ring 41 rotates, the outer ring 41 and the low-speed shaft 45 are connected by the power transmission means 82, so that the low-speed shaft 45 rotates about its axis.

  That is, in the present invention, the sun shaft 42 and the second sun roller 43B are integrated by means of rotating integrally, and the first sun roller 42A and the cam ring 87 are provided coaxially with respect to the sun shaft 42. It is fastened by means capable of rotating integrally with the sun shaft 42. Opposing cam surfaces 95a and 95b are formed on the first sun roller 43A and the cam ring 87, and power is transmitted between the cam ring 87 and the first sun roller 43A by the engagement of the cam surfaces 95a and 95b. The sun shaft 42 is supported by a bearing so as not to move in the axial direction. The planetary roller 44 that contacts the first sun roller 43A and the second sun roller 43B is supported by a bearing so that it can only rotate and can move in the axial direction. Further, the outer ring 41 in contact with the planetary roller 44 is rotatable and axially movable. Further, the planetary roller 44 and the outer ring 41 cannot be displaced relative to each other in the axial direction when a normal force is applied to the planetary roller 44 and the outer ring 41. Moreover, the low speed shaft 45 that is one of the input and output shafts and the outer ring 41 are fastened by torque transmitting means (power transmitting means 82) that can slide in the axial direction.

  For this reason, since the revolution of the planetary roller 44 can be eliminated, the agitation resistance of the lubricating oil can be reduced, and high speed rotation can be dealt with. Further, since the planetary roller 44 can be moved in the axial direction, the normal force acting between the two sun rollers 43A and 43B and the planetary roller 44 can be moved freely in the axial direction. Therefore, it is not necessary to support the sun shaft 42. For this reason, it is not necessary to connect one of the input / output shafts by a joint portion that can slide in the axial direction, and the axial length can be reduced.

  Further, the power transmission means 82 between the outer ring 41 and the low speed shaft 45 is formed by a fitting structure constituted by a notch portion 84 and a protruding portion 85 fitted thereto, and this fitting structure is Since it arrange | positions at the outer-diameter side of the outer ring 41, the expansion of the axial direction by providing this fitting structure can be prevented. Further, the skew moment of the outer ring 41 can be reduced, which is advantageous for smooth rotation.

  By providing the elastic member 94 that generates an axial load, it is possible to improve the power transmission performance at the time of low load, and it is possible to suppress an excessive slip and to prevent a decrease in function due to wear or the like. Further, if the end of the sun shaft 42 is inserted into the hole 63 on the low speed shaft, and the end of the sun shaft 42 is supported by the low speed shaft 45 in the hole 63, the axial size can be reduced. I can plan more.

  Further, the planetary roller 44 and the outer ring 41 come into contact with the sun axis (that is, the transmission axis O) at two points forming a predetermined contact angle, whereby the planetary roller 44 and the outer ring 41 are contacted. The relative displacement in the axial direction is restricted. As a result, power transmission between the planetary roller 44 and the outer ring 41 is stabilized, and a high-quality planetary roller transmission is obtained.

  Next, FIG. 7 shows a modified example of the torque cam 89. In this case, the first sun roller 43A has an axial length of the small diameter portion 70a longer than that of the large diameter portion 70b, and the large diameter portion 73b of the sun roller 43A. And the annular space 98 formed by overlapping the large diameter portion 90b of the cam ring 87 is made small. For this reason, the elastic member 94 is not inserted into the annular space 98.

  Therefore, a flange 99 is provided on the protruding shaft portion 56 side of the cam ring 87, and a disc spring 94 b is externally fitted to the flange 99. A spacer 100 is interposed between the spring 94b and the retaining ring 92a. For this reason, even if it is what is shown in this FIG. 7, the 1st sun roller 43A can be pressed to the anti-projection axial part side with the elastic force of the disc spring 94b. For this reason, there exists an effect similar to the torque cam 89 shown in FIG. 1 and FIG.

  Incidentally, the torque cam 89 shown in FIG. 7 or the torque cam 89 shown in FIG. 4 or the like is a steel ball as a rolling element 88 between the sun roller 43A and the cam surfaces 95a and 95b of the cam ring 87. The moving body 88 may be a roller. Alternatively, a torque cam (face cam) having a structure in which the two cam surfaces can directly mesh with each other without providing the rolling elements 88 between the cam surfaces 95a and 95b may be used.

  In the above-described embodiment, the planetary roller 44 and the outer ring 41 are in contact with each other at two points that form a predetermined contact angle with the sun axis, but the planetary roller 44 and the outer ring 41 are at one point. You may make it contact with. In this case, as shown in FIG. 8, the rolling surface 101 made of the crowning convex portion is formed on the outer diameter surface of the planetary roller 44, and the rolling surface 102 made of the crowning concave portion is formed on the inner diameter surface of the outer ring 41. That's fine.

  Even in the configuration shown in FIG. 8, the axial relative displacement between the planetary roller 44 and the outer ring 41 can be restricted. As a result, power transmission between the planetary roller 44 and the outer ring 41 is stabilized, and a high-quality planetary roller transmission is obtained.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the number of planetary rollers 44 is not limited to three. The member 94 may also be constituted by a ring-shaped member made of rubber, synthetic resin, or the like other than a coil spring or a disc spring. Moreover, in the fitting structure which is the power transmission means 82, the combination of the notch portion 84 and the protruding portion 85 fitted thereto is not limited to two, and may be three or more. Further, the extension portion 62b of the low speed shaft 45 may be provided with a notch portion 84, and the outer ring 41 may be provided with a protruding portion 45 that fits into the notch portion 84. The support shaft 74 that supports the planetary roller 44 may be directly planted in the casing (housing) 46 without being provided on the base 76. Further, the sun shaft 42 and the second sun roller 43A may be formed separately without being integrally formed, and connected using a connecting means such as a spline or a keyway.

It is sectional drawing which shows the planetary roller type transmission which shows embodiment of this invention. It is the sectional view on the AA line of the said FIG. The low-speed axis | shaft of the said planetary roller type transmission is shown, (A) is a front view, (B) is principal part sectional drawing. It is an expanded sectional view of the torque cam of the planetary roller type transmission. The torque cam in a planetary roller type transmission is shown, (A) is principal part sectional drawing at the time of no load, (B) is principal part sectional drawing at the time of load. It is a front view of the opposing surface of the sun roller or cam ring which has a cam surface which comprises the torque cam of FIG. It is an enlarged view which shows the modification of the torque cam of the said planetary roller type transmission. It is principal part sectional drawing which shows the other planetary roller type transmission which shows embodiment of this invention. It is sectional drawing of the conventional planetary roller type transmission. It is sectional drawing of the planetary roller type transmission which has the conventional variable pressurization mechanism.

Explanation of symbols

41 Outer ring 42 Sun shaft 43A Sun roller 43B Sun roller 44 Planetary roller 45 Low speed shaft 58, 71, 72, 73, 78, 79 Rolling surface 82 Power transmission means 87 Cam ring 92 Axial movement restricting means 94 Elastic members 95a, 95b Cam surface

Claims (4)

A sun shaft, a low speed shaft, a pair of first and second sun rollers having a rolling surface on the outer peripheral surface, and an outer ring having a rolling surface on the inner peripheral surface are coaxially arranged, and the first and second sun rollers A plurality of planetary rollers are arranged in the space between the outer ring and the outer ring so as not to revolve at equal intervals in the circumferential direction, and the rolling surfaces of the first and second sun rollers have a contact angle with respect to the axis of the sun axis. A cam ring rotating in unison with the sun axis is connected to the sun axis by transmitting power between the second sun roller and the sun axis by means of rotating in contact with the rolling surface and rotating the second sun roller and the sun axis together. The first sun roller is provided on the same axis, and the first sun roller and the cam ring are formed with a cam surface facing each other. The first sun roller is formed by direct meshing between the cam surfaces or via a rolling element provided between the cam surfaces. Power is transmitted between the cam ring In the planetary roller type transmission axial movement of the first sun roller and the cam ring is restricted by an axial movement regulating means provided on the sun shaft,
Said plurality of planetary rollers, as well as the revolution is capable bearing support is rotatably and axially moved while being restricted, the sun shaft is bearing supported so as axial movement is restrained, and A Utaringu Is connected to the low-speed shaft through the power transmission means so as to be movable in the axial direction, and the power transmission means has a fitting structure constituted by a notch portion extending in the axial direction and an axial protrusion portion fitted thereto. The fitting structure is arranged on the outer diameter side of the outer ring, and the end of the sun shaft is inserted into the hole provided in the low speed shaft up to the position corresponding to the pivot portion of the low speed shaft, A planetary roller transmission characterized in that an end of a sun shaft is supported by a bearing in a hole of a low-speed shaft . The elastic member for generating an axial load is provided between at least one of the first sun roller and the cam ring or between the cam ring and the axial movement restricting means . Planetary roller type transmission. The planetary roller and the outer ring are in contact with each other at two points forming a predetermined contact angle with respect to the axis of the sun axis, and the axial relative displacement between the planetary roller and the outer ring is restricted. The planetary roller transmission according to claim 2. The planetary roller and the outer ring are brought into contact at one point by the crowning convex portion and the crowning concave portion to regulate axial relative displacement between the planetary roller and the outer ring . Any planetary roller transmission.

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