JPH05321997A - Friction type continuously variable transmission - Google Patents

Abstract

PURPOSE:To prevent noise from occurring by including speed change ratio O in the speed change range of a half toroid type continuously variable transmission. CONSTITUTION:An input shaft 6 transmits rotation to an input disc 14, for example, through a running-over cam type propellant force generating device 17. The half-toroid type continuously variable transmission mechanism 11 is provided with an output disc 18 which faces the input disc 14, and a power roller 20 which transmits speed variable rotation to the output disc 18 by bridging and oscillating them. The top end of the input disc 14 is a cone-shaped sun roller 44, the back surface of the output disc is a cone-shaped ring roller 54, and a cone-shaped planetary roller 22 is engaged with the sun roller and the ring roller to constitute a planetary friction wheel transmission mechanism 19. The propellant force generating device 17 applies pressure contact force to all the friction wheels at the same time. Output rotation is taken from the carrier 28 of the planetary roller 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuously variable transmission used for transmitting a rotational driving force of an engine to an auxiliary machine such as a refrigerant compressor of an air conditioner for a vehicle.

[0002]

2. Description of the Related Art Conventionally, as one of continuously variable transmissions of this type,
A half-toroid type continuously variable transmission is known, and its structure is described in, for example, Japanese Patent Laid-Open No. 174750/1983. That is, an input disk and an output disk each having a half-toroidal type, that is, a donut-shaped friction engagement surface of a half-division are connected to an input shaft and an output shaft arranged coaxially, and between these disks, A plurality of power rollers frictionally engaged with these are rotatably supported by trunnions, and each trunnion is connected to a link mechanism to be rotatable. Then, the central axis of the power roller is tilted by the rotation of the trunnion, and the contact portion (radial position) with which the power roller engages the input disk and the output disk is changed to change the speed between the input shaft and the output shaft. The ratio changes.

[0003]

The transmission ratio of such a half-toroid type transmission is generally 0.5 to 2.
The one in which a friction type speed reducer similar to a planetary gear device is inserted between the output disk and the output shaft is also disclosed in JP-A-63-11.
As described in Japanese Patent No. 1356, since the carrier supporting the planetary rollers is fixed and does not revolve in this example, the gear ratio cannot be set to 0, and these transmissions are used for a vehicle air conditioner. In this case, an electromagnetic clutch or the like must be used on the drive side in order to obtain a gear ratio of 0 when cooling is not required in winter.

Japanese Patent Application Laid-Open No. 3-223555 discloses a half-toroidal type transmission combined with a planetary gear unit. However, the planetary gear unit produces noise and the gear teeth are There is a problem of durability due to wear, and further, there is a problem of poor transmission efficiency at light load, and it is possible to expect a synergistic effect by combining with a friction type half toroid type transmission. Can not. The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a half-toroid type continuously variable transmission that can easily and stably realize a complete gear ratio 0 state.

[0005]

In order to solve the above-mentioned problems, the present invention has a half-toroidal first engaging surface having an axis as a center and is rotatably provided around the axis. An input disk, and an output disk member that is rotatably provided around the axis and has a half-toroidal second engaging surface that is centered on the axis and that faces the first engaging surface, It is provided around the axis and frictionally engages with the first and second engagement surfaces to transmit rotation between the input disk and the output disk, and also with the first and second engagement surfaces. A half-toroid type continuously variable transmission mechanism including a plurality of power rollers for changing a contact portion and changing a gear ratio between the input disc and the output disc, and a conical sun formed integrally with the input disc. Roller and the output disk And a conical planetary roller that is integrally formed with the sun roller, the conical planetary roller that frictionally engages with the sun roller and the ring roller and revolves due to the difference in their rotation, and that supports the planetary roller. A planetary friction wheel transmission mechanism composed of a carrier that allows its rotation and revolution and outputs power, and is provided at a proper position on the axis to constitute the half toroid type continuously variable transmission mechanism and the planetary friction wheel transmission mechanism. Provided is a friction continuously variable transmission in which a thrust generating device that simultaneously applies frictional pressure contact force to each friction wheel is coupled.

[0006]

The operation of the half-toroid type continuously variable transmission mechanism is well known, and the power roller is tilted between the input disk and the output disk so that the contact point with respect to the first and second engagement surfaces is increased. The effective radius of the signal changes reciprocally, and the gear ratio between the input disk and the output disk changes continuously. Since these disks are respectively integrated with the sun roller and the ring roller of the planetary friction wheel transmission mechanism, the revolution of the planetary roller corresponding to the difference in the peripheral speed of these rollers is output to the carrier. In the present invention, a sun roller that constitutes a planetary friction wheel transmission mechanism,
Since the ring roller and the planetary roller are all conical friction wheels, the thrust generator provided to press the input and output discs of the half-toroid continuously variable transmission mechanism against the power roller is the same as the sun roller for the planetary roller. It gives a slight movement in the axial direction of the ring roller. Since these are conical, the friction wheels bite in each other in the axial direction, and the friction friction contact force required by the planetary friction wheel transmission mechanism can be obtained at the same time. The output rotation is taken out from the carrier, but its shift range covers the range of the gear ratio 0 and the forward / reverse rotation steplessly.

[0007]

1 and 2 show the construction of a combination of a continuously variable transmission and a compressor as an embodiment of the present invention.
This continuously variable transmission is an organic combination of a half toroid type continuously variable transmission mechanism and a planetary friction wheel transmission mechanism using a conical friction wheel. This half-toroid type continuously variable transmission 11 has the following structure. First, in the front housing 2 and the rear housing 4, an input shaft 6 and an output shaft 8 are arranged coaxially with each other, and rotatably provided around a central axis A. The input shaft 6 is a pulley 10
It is connected to an engine (not shown) via and rotates in synchronization with the engine. The output shaft 8 also serves as the rotation shaft of the compressor 12. The cam disk 16 is integral with the input shaft 6, and the cam disk 16 and the input disk 1 facing it.
On each surface of No. 4, a plurality of sets of cam surfaces 16a and 14a as recesses whose depths continuously change are formed along the peripheral edge as shown in FIG. 5, respectively.
By sandwiching the cam ball 15 between them, a riding cam type thrust generating device 17 is configured. Input disk 14
A power roller 20 which is a rotor is provided between the output disk 18 and the output disk 18, and the power roller 20 frictionally engages with these disks 14 and 18 to transmit the rotation of the input disk 14 to the output disk 18.

A planetary friction wheel transmission mechanism 19 using a conical friction wheel group is provided between the input disk 14 and the output disk 18 and the output shaft 8. That is, the tip of the input disk 14 is conically pointed to form the sun roller 44, and the end surface of the output disk 18 is conically recessed to form the ring roller 54. These rollers 44, 5
A plurality of planetary rollers 22 frictionally engaged with the shaft 4 are supported by a common carrier 28 via bearings 24.
The carrier 28 is connected to the output shaft 8 by a spline 57 so as to rotate integrally therewith, and the left partition wall 72 is provided.
The thrust bearing 59 provided between the thrust generating device 17 and the input disk 14, the power roller 20,
And the thrust transmitted through the output disk 18 is received.

Therefore, the rotation of the engine is changed on the one hand through the input shaft 6, the thrust generating device 17, the input disk 14, the power roller 20, and the output disk 18, and the ring roller 54 of the planetary friction wheel transmission mechanism 19 is changed. To the sun roller 44 of the planetary friction wheel transmission mechanism 19 without being directly shifted from the input disk 14.
And the revolution of the planetary roller 22 corresponding to the difference in peripheral speed between the two is taken out to the output shaft 8 which rotates integrally with the carrier 28, and the compressor 12 is driven thereby. The rotation speed of the compressor 12, that is, the gear ratio between the input / output shafts 6 and 8 is controlled by the posture of the power roller 20 as described later.

The cam disk 16 integrally formed in the middle of the input shaft 16 in the direction of the central axis A has a disk shape centered on the axial line A, and the thrust generator 17 is provided on the side surface facing the input disk 14 as described above. The thrust bearing 26 is formed between the front housing 2 and the front housing 2, and receives a thrust force in the direction of the axis A. The shaft seal 34 includes the front housing 2 and the input shaft 6.
It is arranged between the outer peripheral surface of the continuously variable transmission and the outer peripheral surface thereof so that the refrigerant in the continuously variable transmission does not leak to the outside.

The input disk 14 has a shape of a rotary body centered on the central axis A of the input shaft 6 and has a first engaging surface 36. The first engagement surface 36 is a halved donut-shaped (half-toroidal) curved surface, and the cross-sectional shape passing through the axis A is an arc centered on a swing center axis B of the power roller 20 described later. Tip portion 38 extending from the input disk 14
Is fitted into a through hole 40 formed in the output disk 18, and is rotatably supported by a bearing 42 in this hole 40. The output disk 18 also has the shape of a rotating body around the axis A of the output shaft 8 and has a second half-toroidal (half toroidal) second engagement surface 56. The second engaging surface 56 of the output disk 18 is the first of the input disk 14
It is provided so as to face the engaging surface 36 of the.

The trunnion 58 is a substantially rectangular parallelepiped main body 6
0, a rotation support shaft 62 extending to both sides in the longitudinal direction of the main body 60,
Also, the swing rod 66, which is perpendicular to the axis B of the rotation support shaft 62 and has an axis C directed to a central axis A ′ of the trunnion housing 64, which will be described later, is press-fitted into the central portion of the main body 60. Has been formed. The power roller 20 is rotatably supported by the trunnion 58 via a bearing 68 between the power roller 20 and the swing rod 66, and a bearing 70 between the power roller 20 and the main body 60. Input disk 14 and output disk 1
The surface of the power roller 20 engaging with 8 is a part of a spherical surface.

3 and 4, the trunnion housing 6 is shown.
4 shows a front view and a side view of FIG. Trunnion housing 64
Is substantially annular, and three rectangular window portions 150 for accommodating the trunnions 58 are provided on the circumferential side surface at equal intervals in the circumferential direction. The support wall 152, which faces the window 150 in the circumferential direction, has a trunnion 5 at the center in the width direction.
A through hole 154 for pivotally supporting the rotation support shaft 62 of 8 is formed facing each other.

Referring again to FIGS. 1 and 2, the trunnion housing 64 is provided so as to surround the first and second engaging surfaces 36 and 56, and the three power rollers 20 are connected to the trunnion housing 64. Are provided at equal intervals in the circumferential direction. The trunnion 58 pivots through the pivot shaft 62 into the through hole 154 of the trunnion housing 64 so that the axis C of each rocking rod 66 is directed to the central axis A ′ of the trunnion housing 64 and concentrated at one point. It is supported freely. The trunnion housing 64 is supported on the input / output disks 14 and 18 by the three trunnions 58 and the power roller 20, and the central axis A ′ of the trunnion housing 64 and the axis A of the input / output shafts 16 and 18 are substantially the same. Match. Three anti-rotation pins 74, which are press-fitted and fixed to the surface of the left partition wall 72 facing the trunnion housing 64 at equal intervals in the circumferential direction, are loosely fitted in holes 76 formed in the facing surface of the trunnion housing 64. It

The speed-change ring 78 is an annular member, the outer peripheral surface of which is in sliding contact with the inner peripheral surface of the front housing 2 so as to surround the first and second engaging surfaces 36 and 56 of the input and output disks. Are provided. A cutout groove 156 in the direction of the axis A is formed in a part of the outer peripheral surface of the speed change ring 78, and a tip of a bolt 158 penetrating the front housing 2 is engaged with the cutout groove 156. Therefore, the shift ring 7
8 is movable in the direction of the axis A and is not rotatable about the axis A. The rocking rod 66 is provided on the peripheral surface of the speed change ring 78.
At a position corresponding to the spherical portion 66a formed on the outer end of the
Three through holes 78a are formed toward the center of the speed change ring 78, and a spherical portion 66a is loosely fitted in the through holes 78a.

As a result, as the speed change ring 78 moves in the direction of the axis A, the trunnion 58 is rotated.
It will swing around the fulcrum. This swing reciprocally changes the radius (distance from the axis A) of the portion where the power roller 20 comes into contact with the first and second engagement surfaces 36, 56, and the output disk 18, and thus the ring roller 54. The rotation speed of changes. On the other hand, since the rotation speed of the sun roller 44 is the same as that of the input shaft 6, the planet roller 22 generated by the difference in peripheral speed between the sun roller 44 and the ring roller 54.
The revolution of is taken out from the carrier 28 to the output shaft 8,
The output rotation speed depends on the rotation speed of the output disk 18 which is determined by the axial position of the transmission ring 78.

A holder 80 for the speed change ring 78 has a substantially rectangular parallelepiped shape, and a recess 82 is formed in a lower portion thereof, and the speed change ring 78 is fitted in the recess 82. Holder 80
A through hole 84 having a trapezoidal internal thread is formed on the inner peripheral surface of the through hole 84 at substantially the center thereof. A motor 86, which is rotationally driven in the forward and reverse directions by a control device (not shown), is fixed to the upper part of the rear housing 4, and a motor shaft 88 having a trapezoidal male screw is screwed into the through hole 84 of the holder 80 and The tip is pivotally supported in a bearing hole 90 formed in the front housing 2. Since the holder 80 is displaceable in the direction of the axis A and is not rotatable around the motor shaft 88, the holder 8 is rotated by the rotation of the motor shaft 88.
0 moves in the direction of the axis A, which causes the transmission ring 78
Is also displaced in the direction of the axis A, and the number of rotations of the output disk 18, and thus of the output shaft 8, changes.

The output shaft 8 which also serves as the rotating shaft of the compressor 12 has bearings 44 and 4 formed by a left partition wall 72 and a right partition wall 92.
It is rotatably supported via 5. A plurality of vanes 96 are attached to the rotor 94 fitted to the output shaft 8, and these vanes 96 are in sliding contact with the inner wall surface 100 of the cylindrical pump housing 98 provided on the outer peripheral side thereof. The vane 96 and the inner wall surface 100 form a variable volume chamber,
The variable volume chamber changes its volume by the rotation of the output shaft 8, and sucks the refrigerant (generally gas) of the air conditioner from the suction chamber 102 formed on the left side of the left partition wall 72 through a suction port (not shown). Then, this is compressed and discharged into the discharge chamber 104, and discharged from the discharge port 106 through the high pressure chamber 105 to the outside.

The operation of the present embodiment configured as described above will be described below. When the input shaft 6 is rotationally driven by an engine or the like, the cam disk 16 rotates and the input disk 14 is rotated via the thrust generating device 17.
At that time, the cam surface 16a of the cam disk 16 and the cam surface 14a of the input disk 14, which face each other as shown in FIG. 5A in the stationary state, depend on the magnitude of the torque transmitted with the ball 15 interposed therebetween. Figure 5
As shown in (b), the ball 15 is supported at a position on the shallow slope of both cam surfaces. Therefore, a thrust force in the direction of the axis A, which is approximately proportional to the transmitted torque, is generated and pushes the input disk 14 to the right in FIG. 1 by a minute distance. The thrust force in the axial direction urges the input disk 14 to engage with the power roller 20.
The 0 is also pressed against the output disc 18 for frictional engagement.

This thrust is transmitted from the output disk 18 to the planetary friction wheel transmission mechanism formed behind the output disk 18, and since the friction engagement surfaces of the ring roller 54 and the planetary roller 22 are conical, Giving frictional pressure contact force between. Further, a conical sun roller 44 is formed at the right end of the input disk 14 which is pushed in the axial direction by the same thrust, and it is in frictional engagement with the conical planet roller 22 so that it is between them. Also, frictional pressure contact force is generated according to the magnitude of the transmission torque. The thrust is finally received by the thrust bearing 59 that supports the carrier 28. On the opposite side, the thrust bearing 26 receives the thrust acting on the cam disk 16.

In this way, the rotation of the input shaft 6 is speed-changed and transmitted to the output shaft 8, so that the compressor 12 operates at an arbitrary rotation speed. The speed ratio changes steplessly by rotating the motor 86 in the forward and reverse directions to change the axial position of the speed change ring 78 and changing the rotational speed of the output disk 18. In this case, the planetary friction wheel transmission mechanism 19 is used. Because it incorporates a half-toroid type continuously variable transmission mechanism 1
If only 1, the change range of the gear ratio in the range of 0.5 to 2 is 0.
.About.1.33, a gear ratio of 0 (output shaft 8 stopped) may be included. This occurs when the motor 86 is controlled so that the rotation speed ratio between the input disk 14 and the output disk 18 is 1: 1.5. In this state, the peripheral speeds of the sun roller 44 and the ring roller 54 are opposite to each other and the absolute values are equal. Therefore, the planetary roller 22 only rotates and does not revolve, so that the carrier 28 and the output shaft 8 are stopped, and the input is stopped. Even if the shaft 6 rotates, the compressor 12 is not driven. Note that this is not necessary in this embodiment,
It is also possible to reverse the output shaft 8 by passing the speed ratio 0.

To change the gear ratio, the motor 8
6 drives the motor shaft 88 to rotate so as to displace the holder 80 and the speed change ring 78 in the direction of the axis A. By this, the trunnion 58 is swung around the rotation support shaft 62 and the power roller 20 and First and second engagement surfaces 36,
The contact area with 56 can be changed. As described above, according to the illustrated embodiment, it is possible to provide a continuously variable transmission that can easily and stably realize a complete gear ratio 0 and output rotation in the opposite direction as necessary. ..

The swing displacement of each power roller 20 is
It suffices to displace the speed change ring 78 in the direction of the axis A, and each power roller 20 and the first and second engagement surfaces 36, 5 may be displaced.
The contact state with 6 is not easily made uniform, and some power rollers 20 do not slip and the transmission efficiency is not lowered. Further, in the present embodiment, the thrust generating device 17 applies the pressing force required for frictional engagement not only between the input and output discs 18 and the power roller 20 but also a large number of roller groups constituting the planetary friction wheel transmission mechanism 19. Since it is obtained at the same time, the minimum necessary pressing force according to the magnitude of the transmission torque is generated on all friction engagement surfaces as a characteristic of the riding cam, so excessive friction is generated even with a simple structure. Also, the transmission efficiency at light load is improved.

In this embodiment, the frictional pressure contact force is generated by the thrust generating device 17 utilizing the riding cam, but the thrust generating device 17 can be replaced by, for example, a spring or a hydraulic cylinder. Further, the present invention is not limited to driving the compressor 12, but can be applied to other driving targets.

[0025]

As described above, according to the present invention, it is possible to easily and stably realize a complete gear ratio 0 and a driving state as required by a half-toroid type transmission. Moreover, since the frictional transmission is all used, there is no gear noise and no gear wear problem occurs. Further, since the frictional pressure contact force can be generated by a common thrust generator, the entire mechanism becomes simple.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

2 is a cross-sectional view of the embodiment of FIG.

FIG. 3 is a partially cutaway sectional view of a trunnion housing.

FIG. 4 is a side view of the trunnion housing.

FIG. 5 is a partial cross-sectional view showing an embodiment of a thrust generating device, (a) illustrating a stopped state and (b) illustrating an operating state.

[Explanation of symbols]

 6 ... Input shaft 8 ... Output shaft 11 ... Half-toroid type continuously variable transmission mechanism 12 ... Compressor 14 ... Input disk 15 ... Cam ball 16 ... Cam disk 17 ... Thrust generating device 18 ... Output disk 19 ... Planetary friction wheel transmission mechanism 20 ... Power Roller 22 ... Conical planetary roller 26 ... Thrust bearing 28 ... Carrier 36 ... First engagement surface 44 ... Conical sun roller 54 ... Conical ring roller 56 ... Second engagement surface 57 ... Spline 58 ... Trunnion 59 ... Thrust bearing 64 ... Trunnion housing 66 ... Oscillating rod 78 ... Shift ring 80 ... Holder 86 ... Motor 88 ... Motor shaft A ... Input / output shaft axis

Claims (1)

[Claims] 1. An input disk having a half-toroidal first engaging surface centered on an axis and rotatably provided about the axis, and rotatably provided about the axis, An output disc member having a second half-toroidal engagement surface that is centered on the axis and faces the first engagement surface; and an output disk member that is provided around the axis and that includes the first and second engagement surfaces. The frictional engagement with the mating surface transmits rotation between the input disc and the output disc, and the contact portion with the first and second engagement faces is changed to change the gear ratio between the input disc and the output disc. , A half-toroid type continuously variable transmission including a plurality of power rollers, a conical sun roller integrally formed with the input disk, and a conical sun roller integrally formed with the output disk. Ring roller and the thick Consists of a conical planetary roller that frictionally engages with the positive roller and the ring roller and revolves due to the difference in their rotations, and a carrier that supports the planetary roller and allows its rotation and revolving and takes out an output. A planetary friction wheel transmission mechanism, and a thrust generating device that is provided at a proper position on the axis line and that simultaneously applies frictional pressure contact force to each friction wheel that constitutes the half toroid type continuously variable transmission mechanism and the planetary friction wheel transmission mechanism. Friction continuously variable transmission that is combined with and.