JP2009047218A - Continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify a structure, to reduce the size and the cost, and to enhance the transmission efficiency and the functional reliability in a continuously variable transmission using the traction force. <P>SOLUTION: A continuously variable transmission includes one input shaft 20, two traction speed change units U symmetrically provided in a housing so as to separately perform the continuously variable transmission of the rotational speed of the input shaft by the traction force, a differential transmission mechanism 100 for changing and transmitting each rotational speed changed by the two traction speed change units into one rotational speed, and one output shaft 110 for outputting the rotational speed to be output by the differential transmission mechanism. Thus, continuously variable transmission can be performed while boosting the torque of one input shaft by the two speed change units, and even when the relative gear ratio is deviated between the two traction speed change units, the differential transmission mechanism adjusts the deviation of the gear ratio, and outputs one gear ratio (rotational speed). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a continuously variable transmission that continuously changes the rotational speed of an input shaft and transmits it to an output shaft by a traction drive that uses a traction force. The present invention relates to a continuously variable transmission that performs step shifting.

As a conventional continuously variable transmission, an input shaft and an output shaft that are rotatably supported by a housing via bearings, a frustoconical sun roller (inner ring) provided to rotate integrally with the input shaft , A holder (retainer) rotatably supported on the input shaft, a plurality of tapered rollers (planetary rollers) rotatably supported on the holder and rolling on the outer peripheral surface of the sun roller, and rotating integrally with the output shaft And an output ring (driven outer ring) circumscribing the taper roller, a transmission ring (rotating fixed outer ring) circumscribing a conical part integrally provided on the taper roller and reciprocatingly driven only in the generatrix direction of the conical part. It is known (see, for example, Patent Document 1).
In this continuously variable transmission, when the input shaft rotates, the sun roller rotates integrally, the taper roller that circumscribes the sun roller rotates and revolves, and the output ring rotates due to the rotation of the taper roller. The shaft rotates, and the rotational speed of the output shaft is increased or decreased according to the position of the transmission ring.

However, in this continuously variable transmission, the normal load on the contact surface between the taper roller (planetary roller) and the sun roller, the normal load on the contact surface between the taper roller and the output ring, and the contact surface between the conical portion of the taper roller and the transmission ring. The normal load depends on the initial assembly accuracy and there is no means to correct the fluctuation of the normal load due to changes over time, so the necessary traction force cannot be obtained and the shifting operation is performed reliably. There is no fear.
Along with the normal load, a thrust load is generated in the axial direction of the input shaft and output shaft, and this thrust load is received by the bearing or housing of the input shaft and output shaft. There is a risk that the temperature of the lubricating oil will rise due to a large deformation or heat generation in the bearing area, which may lead to wear, a decrease in power transmission efficiency, or the like. On the other hand, when the rigidity of the housing is increased to cope with deformation and the like, an increase in size or weight is caused.
Further, when the position of the transmission ring is moved by the drive mechanism to adjust the contact position with the taper roller, the change of the transmission ring may occur due to changes in the drive mechanism over time or wear of the contact area between the transmission ring and the taper ring. There is a possibility that it is difficult to control to the original gear ratio because the position is shifted.

JP-A-6-280961

  The present invention has been made in view of the circumstances of the above-described conventional apparatus, and its object is to achieve sufficient traction while simplifying the structure, downsizing, improving functional reliability, and the like. It is an object of the present invention to provide a continuously variable transmission that can secure force or transmission torque, reduce costs, improve transmission efficiency, and can reliably set a desired gear ratio.

The continuously variable transmission according to the present invention is a surface perpendicular to the axial direction of the input shaft so that the input shaft provided rotatably in the housing and the rotational speed of the input shaft are continuously variable by the traction force. Two traction transmission units provided in the housing so as to face each other symmetrically, and a differential transmission mechanism for converting the respective rotational speeds shifted by the two traction transmission units into a single rotational speed and transmitting them. And one output shaft rotatably provided on the housing to output the rotational speed output by the differential transmission mechanism.
According to this configuration, the rotational driving force of one input shaft is continuously variable by the two traction transmission units, and the rotational speeds shifted to each are converted into one rotational speed via the differential transmission mechanism. And output as a rotational driving force from one output shaft.
In this way, the torque of one input shaft can be continuously variable while being doubled by the two traction transmission units, and even if there is a relative gear ratio shift between the two traction transmission units, Even in a region where the value is small and difficult to adjust, the differential transmission mechanism adjusts the shift of the gear ratio to obtain one gear ratio (for example, one rotational speed corresponding to the gear ratio that forms the average value of the two). Can be output.
Therefore, a desired speed change function can be ensured without particularly setting the assembly of the two traction speed change units with high accuracy, and the gear ratio can be easily adjusted near zero. Thus, the influence of the shift of the gear ratio between the two traction transmission units can be prevented, and the transmission efficiency can be improved.
Further, since the two traction transmission units are arranged so as to face each other symmetrically with respect to the plane perpendicular to the axial direction of the input shaft, the thrust load in the axial direction of the input shaft generated in each of the two traction transmission units. Can be canceled by acting in opposite directions to each other, and therefore, an excessive load can be prevented from being applied to the housing or the bearing of the input shaft, and the temperature of the lubricating oil in the bearing region or the like can be prevented. The rise can be suppressed, and therefore, a lubricating oil film can be formed at the contact interface to reliably obtain the traction force.

In the above configuration, each of the two traction speed change units includes a truncated cone-shaped sun roller that rotates integrally with the input shaft, a plurality of planetary rollers that roll on the outer peripheral surface of the sun roller, and a planetary roller that is inscribed and rotated. A movable output ring and a conical portion formed integrally with the planetary roller are inscribed in a freely movable manner and moved in the axial direction of the input shaft so as to change the speed by moving the inscribed position. It is possible to employ a configuration that includes a provided transmission ring.
According to this configuration, the rotational driving force input from one input shaft is transmitted through the sun roller → the plurality of planetary rollers → the output ring while appropriately driving the transmission ring in one traction transmission unit, and the other In this traction transmission unit, while driving the transmission ring appropriately, both are guided to the common differential transmission mechanism via the sun roller → the plurality of planetary rollers → the output ring, and output from one output shaft.
By adopting such a configuration, the structure of the two traction transmission units can be simplified, and by adopting common parts, the types of parts can be reduced and the cost can be reduced.

In the above-described configuration, it is possible to employ a configuration that includes one drive mechanism that synchronously drives a transmission ring included in one of the two traction transmission units and a transmission ring included in the other of the two traction transmission units.
According to this configuration, since the two speed change rings are driven synchronously by one drive mechanism, basically, the gear ratio deviation can be prevented from occurring in the two traction speed change units. Even if this occurs, the differential transmission mechanism can adjust the shift of the gear ratio, so that it is possible to reliably transmit the driving force of one input shaft → two traction transmission units → one output shaft. it can.

In the above-described configuration, the differential transmission mechanism adopts a configuration including a differential gear that converts and transmits each rotational speed output from the output ring included in the two traction transmission units into one rotational speed. Can do.
According to this configuration, since the differential gear is adopted as the differential transmission mechanism, the driving force can be reliably transmitted while adjusting the rotational difference between the two output rings as compared with the case of using a roller or the like. If the input side and the output side of a differential gear mounted on a vehicle or the like are applied in opposite directions, the basic design can be used.

In the above configuration, it is possible to employ a configuration including a loading cam mechanism that can transmit a rotational force between the output ring and the differential transmission mechanism and can generate a pressing force in the direction of the input shaft.
According to this configuration, the rotational driving force of the input shaft is transmitted to the output shaft via the sun roller → the planetary roller → the output ring → the loading cam mechanism → the differential transmission mechanism. The force (normal load), that is, the traction force for pressing the output ring against the planetary roller is increased via the dynamic transmission mechanism → loading cam mechanism. As a result, even when load torque is applied from the outside, the traction force is reliably obtained, and the output shaft is reliably rotated at a predetermined gear ratio.

In the above configuration, it is possible to employ a configuration in which a trigger mechanism for turning on / off the transmission of the rotational force by the traction force between the sun roller and the planetary roller is provided according to the rotational speed of the input shaft.
According to this configuration, the sun roller and the planetary roller are not always directly connected (in close contact with each other so as to generate traction force), but when the rotation speed of the input shaft (sun roller) increases, the trigger mechanism is turned on and the sun roller Since the rotational driving force of the (input shaft) is transmitted to the planetary roller via the traction force, the rotation of the sun roller, that is, the input shaft can be interlocked with the output shaft at a desired timing, while the input shaft (sun roller) When the rotational speed decreases, the trigger mechanism is turned off and the rotational driving force of the sun roller (input shaft) is not transmitted to the planetary roller, so the output shaft is free regardless of the rotation of the input shaft (sun roller) (can be rotated by external force) Can be.

  According to the continuously variable transmission configured as described above, sufficient traction force or transmission torque can be secured, cost can be reduced, transmission can be achieved while achieving simplification of structure, miniaturization, improvement of functional reliability, etc. Efficiency can be improved, and a continuously variable transmission that can be reliably set to a desired gear ratio can be obtained.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments of the invention will be described with reference to the accompanying drawings.
1 to 4 show an embodiment of a continuously variable transmission according to the present invention. FIG. 1 is a partial sectional view showing the inside of the device, FIG. 2 is a sectional view showing the inside of the device, and FIG. FIG. 4 is a schematic view showing a schematic configuration of the apparatus, and FIG. 4 is a schematic view showing a loading cam mechanism forming a part of the apparatus.

  As shown in FIGS. 1 and 2, the continuously variable transmission includes a housing 10, one input shaft 20, two traction transmission units U, one trigger mechanism 80, a loading cam mechanism 90, a differential transmission mechanism 100, One output shaft 110 or the like is provided.

As shown in FIGS. 1 and 2, each of the two traction transmission units U includes a sun roller 30 formed in a truncated cone shape, a plurality of planetary rollers 40 that roll on the outer peripheral surface of the sun roller 30, and a planetary roller 40. The output ring 50 that is in contact with and rotatably supported, and the second conical portion 42 that is integrally formed with the planetary roller 40 are inscribed in a freely rotatable manner, and the speed change ring that changes speed by moving the inscribed position. 60.
The two traction transmission units U include one drive mechanism 70 that drives each transmission ring 60 in synchronization.
Here, in FIGS. 1 to 3, various parts arranged on the left side with respect to a substantially intermediate position of the housing 20 in the axial direction L of the input shaft 20 are referred to as “left side parts” and arranged on the right side. These various parts will be referred to as "right" parts.

That is, as shown in FIGS. 2 and 3 (the trigger mechanism 80 is omitted), the one traction transmission unit U located on the left side includes the sun roller 30, the plurality of planetary rollers 40, the output ring 50, and the transmission ring 60. Similarly, the other traction transmission unit U located on the right side includes a sun roller 30, a plurality of planetary rollers 40, an output ring 50, and a transmission ring 60.
As shown in FIGS. 1 to 3, one traction transmission unit U and the other traction transmission unit U have surfaces (inside the housing 10) perpendicular to the axial direction L of the input shaft 20 with the loading cam mechanism 90 interposed therebetween. Is arranged so as to face each other symmetrically.
Therefore, the two traction speed change units U differentially transmit the rotational force (rotational speed) shifted to each other while canceling the thrust loads generated in the axial direction L of the input shaft 20 by acting in opposite directions to each other. It can be transmitted to the output shaft 120 via the mechanism 110. Therefore, it is possible to prevent an excessive load from being applied to the bearing 10 or the like of the housing 10 or the input shaft 20 which will be described later, and it is possible to suppress an increase in the temperature of the lubricating oil in the bearing region or the like and to obtain a traction force with certainty. be able to. Further, by adopting common parts for the two traction transmission units U, the types of parts can be reduced and the structure can be simplified.

As shown in FIG. 2, the housing 10 includes left and right flange wall portions 11 that rotatably support the input shaft 20, a bearing 12, a ring seal 13, a connecting guide rod 14 that connects the left and right flange wall portions 11, and an outer periphery. Cover 15, one differential transmission mechanism 100 and output shaft 110 are supported and cover 16 is covered, bearing 17, ring seal 18, and the like.
In the housing 10, lubricating oil supplied to a contact interface where the traction force of the traction transmission unit U is generated, other sliding surfaces, rolling surfaces and the like is injected.

As shown in FIG. 2, the input shaft 20 protrudes outside the housing 10 to be transmitted integrally with the external input shaft 21 that receives driving force from an engine or the like, and rotates integrally with the external input shaft 21. It is formed by the internal input shaft 22 connected so as to.
The external input shaft 21 includes a disk-shaped flange portion 21 a and a connection hole 21 b for connecting the internal input shaft 22 at the inner end thereof. The flange portion 21a defines an end face 82 (described later) of the trigger mechanism 80.
The internal input shaft 22 is connected with the two sun rollers 30 so as to face each other so as to rotate integrally and the left sun roller 30 is connected so as to be movable in the axial direction L by a predetermined amount. Yes.

As shown in FIG. 2, the sun roller 30 is formed in a substantially truncated cone shape, an outer peripheral surface 31 that forms a part of a conical surface on which the planetary roller 40 rolls, a cylindrical portion 32 formed on the other end side, a cylinder It is formed so as to include a recess 33 formed inside the portion 32.
The sun roller 30 located on the left side defines an inclined surface 83 that receives the centrifugal weight 81 of the trigger mechanism 80 in the concave portion 33. On the other hand, the sun roller 30 located on the right side is formed so as to accommodate the screw member 34 screwed into the end portion of the internal input shaft 22 in the concave portion 33. The screw member 34 fixes the right sun roller 30 so as to rotate integrally with the internal input shaft 22.
In other words, the left sun roller 30 is coupled so as to rotate integrally with the internal input shaft 22 and slightly moveable in the axial direction L of the internal input shaft 22, and the right sun roller 30 is integrated with the internal input shaft 22. It is fixed to rotate.

As shown in FIG. 2, the planetary roller 40 includes a first conical portion 41 that rolls on the sun roller 30 (outer peripheral surface 31), a tapered second conical portion 42 that is inscribed in the transmission ring 60, a first conical portion 41, and A common shaft portion 43 of the second conical portion 42 is provided.
As shown in FIG. 3, the plurality of planetary rollers 40 included in the left traction transmission unit U are equidistantly arranged in a virtual conical surface in which each shaft portion 43 has a vertex A1 on the right side in the housing 10. Are held by a movable holder 44 on the left side. Further, as shown in FIG. 3, the plurality of planetary rollers 40 included in the right traction transmission unit U are equally spaced in a virtual conical surface in which each shaft portion 43 has a vertex A2 on the left side in the housing 10. Are held by the right movable holder 44 so as to be arranged in the order.
As shown in FIG. 3, the second conical portion 42 of all the planetary rollers 40 has a bus bar (a ridge line with which the transmission ring 60 contacts) M2 located farthest in the radial direction from the internal input shaft 22. Are formed so as to extend in parallel with the axial direction L of the.
The shaft 43 of the planetary roller 40 is held so as to be freely movable within a predetermined range with respect to the movable holder 44. The movable holder 44 is formed in a skeleton structure (birdcage shape), and is held via a bearing on the internal input shaft 22 and the cylindrical portion 32 of the sun roller 30 so as not to come into contact with other components in the housing 10. The planetary roller 40 is held so as to be rotatable around the input shaft 20 (internal input shaft 22).

As shown in FIG. 2, the output ring 50 includes an inner peripheral surface 51 on which the first conical portion 41 of the planetary roller 40 is inscribed and rolls, an annular end surface portion 52 in which the loading cam mechanism 90 is interposed, and the like. Is formed. Further, the right output ring 50 includes a gear 53 that meshes with an outer gear 102a of the differential transmission mechanism 100 described later on the outer periphery thereof.
The output ring 50 is rotated by the traction force as the planetary roller 40 rotates and revolves. Therefore, by increasing the normal load on the inner peripheral surface 51, a larger traction force can be obtained and the rotational force can be reliably transmitted.

  As shown in FIGS. 1 and 2, the transmission ring 60 includes an inner peripheral surface 61 that contacts the second conical portion 42 of the planetary roller 40 and a female screw portion into which a lead screw 71 that forms part of the drive mechanism 70 is screwed. 62, a guided portion 63 that is externally fitted and guided by the connecting guide rod 14 is provided. Then, the transmission ring 60 is held in the housing 10 in a non-rotatable manner around the input shaft 20 (internal input shaft 22) over a predetermined range in the axial direction L of the input shaft 20 (internal input shaft 22). And is supported so that it can reciprocate freely.

As shown in FIGS. 1 and 2, the drive mechanism 70 is disposed in the housing 10 so as to extend in parallel with the input shaft 20 (internal input shaft 22), and is screwed into the female screw portions 62 of the two transmission rings 60. A lead screw 71 to be engaged, a gear 72 fixed to the center of the lead screw 71, a worm 73 meshing with the gear 72, a motor 74 for rotationally driving the worm 73, and the like are provided.
When the motor 74 rotates in one direction, the two transmission rings 60 are driven synchronously toward the center in the axial direction L in FIGS. 1 to 3 via the worm 73 → the gear 72 → the lead screw 71. On the other hand, when the motor 74 rotates in the opposite direction, the two transmission rings 60 are directed to both outer sides in the axial direction L in FIGS. 1 to 3 via the worm 73 → the gear 72 → the lead screw 71. Are driven (moved) synchronously.

That is, by moving the speed change ring 60 in the axial direction L of the input shaft 20, the inscribed position where the second conical portion 42 of the planetary roller 40 is inscribed with the inner peripheral surface 61 is moved, thereby performing a speed change. It has become.
Specifically, as shown in FIG. 3, when the two transmission rings 60 are in contact at a predetermined neutral position N of the second conical portion 42, the planetary roller 40 rolls with respect to the output ring 50. The output ring 50 is stopped without rotating, that is, the output shaft 110 is also stopped.
Next, when the transmission ring 60 is moved toward both sides in the housing 10 (as indicated by the arrow D in FIG. 3), that is, toward the small-diameter end portion of the second conical portion 42, the output The rotation speed of the ring 50 is gradually increased, and the output shaft 110 is also rotated at a higher speed.
On the other hand, the transmission ring 60 is directed toward the opposite side (center side in the housing 10) from the neutral position N (as indicated by an arrow R in FIG. 4), that is, in contact with the large diameter end side of the second conical portion 42. When the position is moved, the output ring 50 rotates in the opposite direction.

  As described above, one drive mechanism 70 drives the transmission ring 60 included in one traction transmission unit U and the transmission ring 60 included in the other traction transmission unit U in synchronization with each other. The gear ratio U can be prevented from causing a gear ratio deviation, and even if a gear ratio deviation occurs, the differential transmission mechanism 100 can adjust the gear ratio deviation. It is possible to reliably transmit the driving force 20 → two traction transmission units U → one output shaft 110.

  The trigger mechanism 80 turns on / off the transmission of the rotational force by the traction force between the sun roller 30 and the planetary roller 40 according to the rotational speed of the input shaft 20, that is, the sun roller 30, as shown in FIG. A plurality of centrifugal weights 81 having a spherical shape, an end surface 82 formed on the flange portion 21a of the external input shaft 21, and a plurality of inclined surfaces 83 formed on the concave portion 33 of the sun roller 30 disposed on the left side.

When the rotation speed of the input shaft 20 (sun roller 30) is increased from the state in which the sun roller 30 and the planetary roller 40 idle with respect to each other (the state in which the traction force on the contact surface does not act), the trigger mechanism 80 Moving to the outside in the radial direction, the inclined surface 83 is pressed, and the sun roller 30 is pressed inward in the axial direction L of the internal input shaft 22 (actuated on). That is, the left and right sun rollers 30 are pressed so as to bite into the corresponding plurality of planetary rollers 40. As a result, a traction force is generated, and the rotational driving force of the input shaft 20 (sun roller 30) is transmitted to the planetary roller 40 and transmitted to the output shaft 110 at a desired timing.
On the other hand, when the rotational speed of the input shaft 20 (sun roller 30) decreases, the centrifugal weight 81 moves closer to the center in the radial direction and the force pushing the inclined surface 83 becomes weaker, so that the sun roller 30 corresponds to the corresponding plurality of planetary rollers 40. It moves slightly so as to get out of (moves off). As a result, the traction force is reduced, the rotational driving force of the input shaft 20 (sun roller 30) is not transmitted to the planetary roller 40, and the output shaft 110 rotates freely regardless of the rotation of the input shaft 20 (sun roller 30) ( It can be rotated by external force).
As described above, when the trigger mechanism 80 is turned on, the sun roller 30 is formed so as to enhance the wedge action, so that the normal load, that is, the traction force on the contact surface between the sun roller 30 and the planetary roller 40 can be reliably obtained. be able to.

  As shown in FIGS. 2 to 4, the loading cam mechanism 90 includes two rotary plates 91 and 92 interposed between the left and right output rings 50 and 50, and a thrust bearing 93 disposed between the rotary plates 91 and 92. , Rolling elements 94 and the like interposed between the left output ring 50 and the rotating plate 91 and between the right output ring 50 and the rotating plate 92, respectively.

As shown in FIGS. 2 and 3, the rotating plate 91 is disposed adjacent to the left output ring 50, and the outer peripheral surface thereof has a gear 91a that meshes with an external gear 101a of the differential transmission mechanism 100 described later, Are formed so as to include a plurality of arc-shaped cam grooves 91 b and the like on the side surface facing the output ring 50. A cam groove 91c that receives the rolling element 94 is formed on the end face 52 of the left output ring 50 so as to face the cam groove 91b of the rotating plate 91.
As shown in FIGS. 2 and 3, the rotating plate 92 is disposed adjacent to the right output ring 50 and includes a plurality of arc-shaped cam grooves 92 b and the like on the side surface facing the right output ring 50. Is formed. A cam groove 92c that receives the rolling element 94 is formed on the end face 52 of the right output ring 50 so as to face the cam groove 92b of the rotating plate 92.
The rotating plate 91 located on the left side and the rotating plate 92 located on the right side are disposed adjacent to each other in the axial direction L of the internal input shaft 22 as shown in FIGS.
The thrust bearing 93 is adapted to receive a thrust load generated by the loading cam mechanism 90.

The loading cam mechanism 90 is interposed between the output ring 50 of the left traction transmission unit U and the output ring 50 of the right traction transmission unit U, as shown in FIGS. A pressing force (thrust load) can be generated in the axial direction L of the shaft 22).
That is, when the loading cam mechanism 90 generates a relative rotational difference between the output ring 50 and the rotating plates 91 and 92, the rolling element 94 moves and cam action is performed by the cam grooves 91b and 91c and the cam grooves 92b and 92c. In response, a pressing force (thrust load) is generated in the axial direction L of the input shaft 20 (internal input shaft 22). As a result, the normal load on the contact surface between the output ring 50 and the planetary roller 40 increases, and the output ring 50 and the rotating plates 91 and 92 rotate integrally as a reaction force of the thrust load.
Specifically, the rotational driving force of the input shaft 20 is transmitted to the output shaft 110 via the sun roller 30 → the planetary roller 40 → the output ring 50 → the loading cam mechanism 90 → the differential transmission mechanism 100, and conversely, the output shaft The load torque of 110 increases the pressing force (normal load), that is, the traction force that presses the output ring 50 against the planetary roller 40 via the loading cam mechanism 90. Therefore, even if the load torque is applied from the outside, the traction force is not increased. The output shaft is reliably rotated and driven at a predetermined speed ratio.
Furthermore, since the one rotary plate 91 and the other rotary plate 92 are arranged adjacent to each other in the axial direction L of the input shaft 20, the apparatus can be consolidated and miniaturized in the axial direction L of the input shaft 20. This can be achieved, and the thrust force acting in the axial direction L of the input shaft 20 can be offset to reduce the load on the thrust bearing 93.

As shown in FIGS. 2 and 3, the differential transmission mechanism 100 integrally includes an outer gear 101 a that meshes with the gear 91 a of the rotating plate 91 and a bevel gear 101 b formed on the inner side, and around the output shaft 110. A gear 101 that is rotatably supported, an external gear 102a that meshes with the gear 53 of the output ring 50 on the right side, and a bevel gear 102b that is formed on the inner side are integrally provided, and are rotatably supported around the output shaft 110. The gear 102, the shaft member 103 connected so as to rotate integrally with the output shaft 110 in a region sandwiched between the two gears 101, 102, the shaft member 103 being rotatably supported, and the bevel gear 101b, Two bevel gears 104, 105 and the like meshing with 102b are provided.
The shaft member 103 rotatably supports the bevel gears 104 and 105 around an axis extending in a direction orthogonal to the axial direction of the output shaft 110.

That is, the differential transmission mechanism 100 is a differential gear including a gear 101 (external gear 101a, bevel gear 101b), gear 102 (external gear 102a, bevel gear 102b), shaft member 103, bevel gear 104, and bevel gear 105. Is formed.
Therefore, when the rotation speeds of the left and right output rings 50 are the same, the gears 101 and 102 rotate around the output shaft 110 at the same speed, so that the bevel gears 104 and 105 mesh with the gears 101 and 102 without rotating. In this state, the shaft member 103 rotates together with the shaft member 103, and the rotation speed is transmitted to the output shaft 110.
On the other hand, when the rotation speeds of the left and right output rings 50 are different, the gear 101 and the gear 102 have a relative rotation difference, and therefore the bevel gears 104 and 105 rotate (rotate) and output together with the shaft member 103. By rotating around the shaft 110, the rotational speeds of both the gears 101 and 102 are averaged to be converted into one rotational speed and transmitted to the output shaft 110.

In this way, the torque of one input shaft 20 can be continuously variable while being doubled by the two traction transmission units U, and even if there is a relative gear ratio deviation between the two traction transmission units U, the differential The transmission mechanism 100 can adjust the shift of the gear ratio and output it as one gear ratio (for example, one rotation speed corresponding to the gear ratio that is the average value of the two).
In addition, since a differential gear is employed as the differential transmission mechanism 100, the driving force can be reliably transmitted while adjusting the rotational difference between the two output rings 50 as compared with the case of using a roller or the like. If the input side and the output side of a differential gear mounted on the same are applied in opposite directions, the basic design can be used.

  As shown in FIGS. 2 and 3, the output shaft 110 is rotatably supported by the housing 10 via a bearing 17 and a ring seal 18, and the gears 101 and 102 can be rotated about its axis. The shaft member 103 that is orthogonal to the axial direction is held so as to rotate integrally.

Next, the operation of the continuously variable transmission will be described.
First, when the input shaft 20 is stopped, no traction force is generated and no torque is transmitted to the two traction transmission units U, so that the output shaft 110 is in a freely rotatable state (off state).
Subsequently, when the input shaft 20 starts rotating from a stopped state and the rotational speed thereof increases, the trigger mechanism 80 is turned on (the centrifugal weight 81 moves radially outward to correspond to the two sun rollers 30). The sun roller 30 is pressed against the planetary roller 40 to generate a normal load, that is, a traction force exceeding a predetermined level, and torque (rotational driving force) is transmitted from the sun roller 30 to the planetary roller 40. The

Then, in the two traction transmission units U, both the transmission rings 60 are appropriately driven by one drive mechanism 70, and the respective rotational speeds shifted through the sun roller 30 → the plurality of planetary rollers 40 → the output ring 50 are directly Alternatively, it is converted into one rotational speed by being input to the differential transmission mechanism 100 via the loading cam mechanism 90, and one output shaft is generated at the rotational speed (speed ratio) output by the differential transmission mechanism 100. 110 rotates.
Here, the torque of one input shaft 20 is continuously variable while being doubled by the two traction transmission units U. Even if there is a relative gear ratio shift between the two traction transmission units U, Even in a region where the gear ratio value is small and difficult to adjust, the differential transmission mechanism 100 adjusts the shift of the gear ratio to obtain one gear ratio (one rotational speed corresponding to the gear ratio forming the average value of both). In order to output, the rotational driving force is reliably transmitted from one input shaft 20 to one output shaft 110 via two traction transmission units U.

  In the traction drive, a thrust load is generated in each of the two traction speed change units U in the axial direction L of the input shaft 20, but the two traction speed change units U (the sun roller 30, the planetary roller 40, the output located on the left and right respectively) are output. Since the ring 50 and the transmission ring 60) are arranged so as to face each other symmetrically with respect to a plane perpendicular to the axial direction L of the input shaft 20, the respective thrust loads are applied in opposite directions to cancel each other. Can do. As a result, it is possible to prevent an excessive load from being applied to the housing 10 or the bearing 12 of the input shaft 20.

  On the other hand, when a load torque is applied to the output shaft 110, the loading cam mechanism 90 operates to increase the pressing force (normal load), that is, the traction force that presses the output ring 50 against the planetary roller 40. Thereby, even when load torque is applied from the outside, the traction force is reliably obtained, and the output shaft 110 is reliably rotated at a predetermined speed ratio.

FIG. 5 is a sectional view showing another embodiment of the continuously variable transmission according to the present invention.
Since this embodiment is the same as the above-described embodiment except that the loading cam mechanism is changed, the same components are denoted by the same reference numerals and description thereof is omitted.
That is, in this embodiment, as shown in FIG. 5, the loading cam mechanism 90 ′ includes one rotating plate 91 ′, the rotating plate 91 ′, and the right output ring 50 interposed between the left and right output rings 50, 50. And a rolling element 94 interposed between the left output ring 50 and the rotating plate 91 ′.

As shown in FIG. 5, the rotating plate 91 ′ is disposed adjacent to the left output ring 50 and the right output ring 50, and meshes with an external gear 101 a of the differential transmission mechanism 100 described later on the outer peripheral surface thereof. The gear 91a is formed to have a plurality of arc-shaped cam grooves 91b and the like on the side surface facing the output ring 50 on the left side. A cam groove 91c that receives the rolling element 94 is formed on the end face 52 of the left output ring 50 so as to face the cam groove 91b of the rotating plate 91 ′.
The thrust bearing 93 ′ is adapted to receive a thrust load generated by the loading cam mechanism 90 ′.

As shown in FIG. 5, the loading cam mechanism 90 ′ is interposed between the output ring 50 of the left traction transmission unit U and the output ring 50 of the right traction transmission unit U, and is connected to the input shaft 20 (internal input). A pressing force (thrust load) can be generated in the axial direction L of the shaft 22).
In other words, when the loading cam mechanism 90 ′ has a relative rotational difference between the output ring 50 and the rotating plate 91 ′, the rolling element 94 moves and receives a cam action by the cam surfaces 91 b and 91 c, and the input shaft 20. A pressing force (thrust load) is generated in the axial direction L of the (internal input shaft 22). As a result, the normal load on the contact surface between the output ring 50 and the planetary roller 40 increases, and the output ring 50 and the rotating plate 91 'rotate integrally as a reaction force of the thrust load.
Specifically, the rotational driving force of the input shaft 20 is transmitted to the output shaft 110 via the sun roller 30 → the planetary roller 40 → the output ring 50 → the loading cam mechanism 90 ′ → the differential transmission mechanism 100, and conversely the output The load torque of the shaft 110 increases the pressing force (normal load) that presses the output ring 50 against the planetary roller 40, that is, the traction force via the loading cam mechanism 90 '. A force is reliably obtained, and the output shaft is reliably rotated at a predetermined speed ratio.
In this embodiment as well, as described above, it is possible to secure sufficient traction force or transmission torque, achieve cost reduction, and increase transmission efficiency while achieving simplification of structure, miniaturization, improvement in functional reliability, etc. It is possible to improve, and it is possible to reliably set a desired gear ratio.

In the above embodiment, the two traction transmission units U include the sun roller 30, the conical planetary roller 40, the output ring 50, the transmission ring 60, and the like. However, the present invention is not limited to this. A traction transmission unit having another structure may be adopted as long as the transmission is performed using force.
In the above-described embodiment, the differential transmission mechanism 100 has a configuration including a differential gear. However, the configuration is not limited to this, and both are provided when the rotational speeds output from both output rings 50 are different. A differential transmission mechanism using a roller and other differential transmission mechanisms can be employed as long as the rotation speed is converted and output as one rotational speed.
In the above embodiment, the case where the loading cam mechanisms 90 and 90 ′ are employed has been described. However, the present invention is not limited to this, and a configuration in which the driving force is directly transmitted from the output ring 50 to the differential transmission mechanism 100. May be adopted.
In the above embodiment, the case where one trigger mechanism 80 is employed has been described. However, the present invention is not limited to this, and the trigger mechanism 80 may be abolished, or two trigger mechanisms 80 are symmetrically arranged. May be adopted.

  As described above, the continuously variable transmission of the present invention can secure sufficient traction force or transmission torque and achieve cost reduction while achieving simplification of structure, miniaturization, and improvement of functional reliability. Since transmission efficiency can be improved and a desired gear ratio can be set reliably, it can be applied as a transmission device mounted on a vehicle or the like, and is input from one input shaft. As long as the rotational driving force is continuously variable and output from one output shaft, it is useful for other driving devices, mechanical devices, machine tools, and the like.

It is a fragmentary sectional view showing one embodiment of continuously variable transmission concerning the present invention. It is sectional drawing which shows the inside of the continuously variable transmission shown in FIG. FIG. 3 is a schematic diagram showing a schematic configuration of the continuously variable transmission shown in FIG. 2. FIG. 2 shows a loading cam mechanism included in the continuously variable transmission shown in FIG. 1, (a) is an exploded perspective view showing an outline, and (b) is a partial sectional view. It is sectional drawing which shows other embodiment of the continuously variable transmission which concerns on this invention.

Explanation of symbols

L Input shaft axial direction 10 Housing 11 Flange wall 12 Bearing 13 Ring seal 14 Connection guide rods 15, 16 Cover 17 Bearing 18 Ring seal 20 Input shaft 21 External input shaft 21a Flange 21b Connection hole 22 Internal input shaft U Traction speed change Unit 30 Sun roller 31 Outer peripheral surface 32 Cylindrical portion 33 Recess 34 Screw member 40 Planetary roller 41 First conical portion 42 Second conical portion 43 Shaft portion 44 Movable holder 50 Output ring 51 Inner peripheral surface 52 End surface portion 53 Gear 60 Transmission ring 61 Inside Peripheral surface 62 Female screw portion 63 Guided portion 70 Drive mechanism 71 Lead screw 72 Gear 73 Worm 74 Motor 80 Trigger mechanism 81 Centrifugal weight 82 End surface 83 Inclined surface 90, 90 'Loading cam mechanism 91, 91', 92 Rotating plate 91a Gear 91b, 91c, 92b, 92 c Cam groove 93, 93 'Thrust bearing 94 Rolling element 100 Differential transmission mechanism (differential gear)
101, 102 Gears 101a, 102a External gears 101b, 102b Bevel gear 103 Shaft member 104, 105 Bevel gear 110 Output shaft

Claims (6)

One input shaft rotatably provided in the housing;
Two traction transmission units provided in the housing so as to face each other symmetrically with respect to a plane perpendicular to the axial direction of the input shaft in order to continuously and continuously change the rotational speed of the input shaft by traction force; ,
A differential transmission mechanism that converts the respective rotational speeds shifted by the two traction transmission units into a single rotational speed and transmits the converted rotational speed;
One output shaft rotatably provided in the housing to output the rotation speed output by the differential transmission mechanism;
Including a continuously variable transmission. Each of the two traction transmission units includes a truncated cone-shaped sun roller that rotates integrally with the input shaft, a plurality of planetary rollers that roll on the outer peripheral surface of the sun roller, and the planetary roller that is inscribed and rotated. A movable output ring and a conical portion formed integrally with the planetary roller are inscribed in a rollable manner and moved in the axial direction of the input shaft so as to change the speed by moving the inscribed position. Including a transmission ring provided in the
The continuously variable transmission according to claim 1. Including one drive mechanism for driving the transmission ring included in one of the two traction transmission units and the transmission ring included in the other of the two traction transmission units in synchronization.
The continuously variable transmission according to claim 2. The differential transmission mechanism includes a differential gear that converts and transmits each rotational speed output from an output ring included in the two traction transmission units into a single rotational speed.
4. The continuously variable transmission according to claim 2, wherein the continuously variable transmission. Including a loading cam mechanism capable of transmitting a rotational force interposed between the output ring and the differential transmission mechanism and generating a pressing force in the direction of the input shaft.
The continuously variable transmission according to any one of claims 2 to 4, characterized in that: A trigger mechanism for turning on / off the transmission of the rotational force by the traction force between the sun roller and the planetary roller according to the rotational speed of the input shaft is provided.
6. The continuously variable transmission according to any one of claims 2 to 5, wherein:

Images