JPH07293655A - Speed change control device for toroidal type continuously variable transmission - Google Patents

Abstract

PURPOSE:To, perform the position adjusting work of a speed change link, for feed backing the speed change condition of a toroidal type continuously variable transmission to a speed change control valve, from outside without leaking hydraulic fluid. CONSTITUTION:A power roller 26 performs power transmission between input/ output cone disks 24 and 25. When the power roller. 26 is offset in an shaft line O3 direction to be tiltedly rotated around a coaxial line under control by a speed change control valve 40, continuously variable speed change is performed to feed back these offsets and tilt rotations to the speed change control valve 40 via a precession cam 46 and a speed change link 47. The position adjustment of the speed change link 47 to the speed change control valve 40 is performed by displacing a speed change link pivotal point 48 depend on the screwing degree of an adjustment screw 52. All this adjustment can be performed from the outside of a transmission case 21 to prevent the leakage of hydraulic fluid in the inside in work to improve workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toroidal type continuously variable transmission, and more particularly to a shift control device thereof.

[0002]

2. Description of the Related Art A toroidal type continuously variable transmission is usually constructed as described in, for example, Japanese Patent Laid-Open No. 3-89066.
This toroidal type continuously variable transmission is, as shown in FIG. 5, a toroidal type composed of coaxially arranged input / output cone disks 1 and 2, and a power roller 3 for transferring power by frictional engagement between these input / output cone disks. It includes a transmission unit and a shift control device as described below.

The shift control device has a step motor 4.
Of the inner and outer valve bodies 5a and 5b of the shift control valve 5, the outer valve body 5b is displaced from the neutral position relative to the inner valve body 5a by a gear shift command from the step motor, so that both power rollers 3 are fluidized. The pressure causes the piston 6 to displace vertically in the drawing, but in opposite directions. Thus both the power roller 3, the rotation axis O ₁ is offset from the illustrated position that intersects the rotation axis O ₂ of the input and output cone discs 1 and 2, the power roller 3 by the offset from the input and output cone discs 1 and 2 With component force, the vehicle can be tilted about its swing axis O ₃ orthogonal to its own rotation axis O ₁ to perform continuously variable transmission.

When the above-mentioned shift command is achieved by such a continuously variable shift, the inner valve body 5a of the shift control valve 5 which feeds back the offset and tilt of the power roller 3 through the recess cam 7 and the shift link 8, It is possible to return to the initial neutral position relatively to the outer valve body 5b and maintain the achievement state of the shift command.

By the way, it is necessary to adjust the initial position of the shift control valve 5 in the neutral position when the transmission link 8 is assembled. Conventionally, the adjustment is performed from the outside by the structure shown in FIG. I was able to do it.

That is, the adjusting screw 9 is screwed into the end of the speed change link 8 facing the inner valve body 5a of the speed change control valve 5, and the tip of the adjusting screw 9 is screwed into the speed change control valve 5. Butt the inner valve body 5a. When adjusting the initial position of the speed change link 8 with respect to the speed change control valve 5 in the neutral position, the cap 11 of the tool hole 10a formed at the position of the transmission case 10 directly facing the adjusting screw 9 is removed, and the tool hole 10a is used to cut the tool. Is inserted to adjust the initial position of the shift link 8 with respect to the shift control valve 5.

[0007]

However, in such a conventional shift control device, the cap 11 of the tool hole 10a formed in the transmission case 10 is removed, and the tool is inserted from the tool hole 10a to perform the work. Because of the configuration that needs to be performed, there are the following problems.

That is, at the level of the tool hole 10a, there is hydraulic oil for lubrication and speed change control of the toroidal type continuously variable transmission, and in the above adjustment work, the hydraulic oil in the transmission is changed to the tool hole. The work had to be performed while leaking from 10a, and the workability of the adjustment work was extremely poor. It should be noted that it is conceivable to drain all the hydraulic oil before the work in order to prevent the hydraulic oil from leaking out of the tool hole 10a during the above-mentioned work, but this adjustment work should be performed while the transmission is shifting. Therefore, it was not possible to drain all the hydraulic oil once.

It is an object of the present invention to solve the above-mentioned problems by providing a shift control device in which the adjusting screw can be operated from the outside of the transmission case.

[0010]

To this end, the first invention is a toroidal transmission comprising an input / output cone disk arranged coaxially and a power roller for transferring power by frictional engagement between the input / output cone disks. A unit is provided to displace the inner and outer valve bodies of the shift control valve relatively from the neutral position in response to a shift command, thereby fluidizing the power roller from a position where the rotation axis intersects with the rotation axis of the input / output cone disc. Offset the power roller by the component force from the input / output cone disk,
By tilting about a swing axis perpendicular to its own rotation axis, a continuously variable gear shift is performed, and when the gear shift command is achieved by the continuously variable gear shift, the offset and tilt of the power roller are precess cam. And a toroidal type continuously variable transmission having a shift control device configured to feed back to the shift control valve via a shift link to relatively return the inner and outer valve bodies to a neutral position and maintain the achievement state of the shift command. In the above, the speed change link is pivotally supported on the adjusting link, and the force point of the adjusting link is engaged with an adjusting screw that is oil-tightly sealed from the transmission case and protrudes to the outside. .

A second invention is characterized in that, in the first invention, the arm length from the pivot point of the adjustment link to the force point is made longer than the arm length from the pivot point to the shift link connecting point. Is.

A third aspect of the invention is that in the first or second aspect of the invention, the pivot point of the adjustment link is pivotally supported with respect to the valve outer casing to which the outer valve body of the shift control valve is fitted. It is a feature.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the invention, a columnar protrusion is provided at the force point of the adjustment link so as to project laterally, and the columnar protrusion is provided at the inner end of the adjustment screw. It is characterized by being engaged with the groove.

A fifth aspect of the invention is characterized in that, in any one of the first to fourth aspects of the invention, the pivot point of the adjustment link is pivotally supported by a fixed member disposed adjacent to the adjustment link. Is.

[0015]

In the first invention, the power roller transfers power by frictional engagement between the input and output cone disks arranged coaxially. Here, when shifting, the inner and outer valve bodies of the shift control valve are relatively displaced from the neutral position by a shift command. The fluid pressure generated by this causes the power roller to be offset from the position where the rotation axis intersects with the rotation axis of the input / output cone disc, and the component force from the input / output cone disc causes the power roller to rotate itself. It is tilted about the swing axis line which is orthogonal to the axis line, so that the transmission ratio between the input and output cone disks, that is, the gear ratio can be changed steplessly. Then, when the shift command is achieved by the continuously variable shift, the offset and tilt of the power roller are fed back to the shift control valve via a recess cam and a shift link to relatively move the inner and outer valve bodies of the shift control valve. To the neutral position, and the state of achieving the shift command is maintained.

By the way, in adjusting the initial position of the transmission link with respect to the transmission control valve in the neutral position, the adjustment link is swung by adjusting the screwing amount of the adjustment screw with respect to the transmission case. Displace the fulcrum. At this time, the shift link moves while being in contact with the recess cam and the shift control valve, and the initial position of the shift link with respect to the shift control valve in the neutral position can be adjusted.

By the way, the speed change link is pivotally supported on the adjusting link, and the force point of the adjusting link is engaged with the adjusting screw which is oil-tightly sealed from the transmission case and protrudes to the outside. Since all the work can be performed from the outside of the transmission case, it is possible to prevent hydraulic fluid from leaking from the transmission case during such work, and improve the workability of the adjustment work.

In the shift control device of the second aspect of the invention, the arm length from the pivot point of the adjustment link to the force point is made longer than the arm length from the pivot point to the shift link connection point. Even if a fine adjustment is required, it can be dealt with by making the adjustment sensitivity dull by the lever ratio represented by. Further, by changing the lever ratio, the adjustment sensitivity can be arbitrarily determined according to the demand, and an additional advantage that it can be applied to any toroidal type continuously variable transmission can be obtained.

Further, in the shift control device of the third aspect of the invention, the pivot point of the adjusting link is pivotally supported with respect to the valve outer casing to which the outer valve body of the shift control valve is fitted. Since the shift control valve and the recess cam are positioned, the relative position of the adjusting link and thus the relative position of the shift link to them can be made accurate.

Further, in the shift control device of the fourth aspect of the present invention, a cylindrical projection is provided at the force point of the adjustment link so as to project in the lateral direction, and the cylindrical projection is engaged with the inner end groove of the adjustment screw.
The engagement between the adjustment screw and the adjustment link can be achieved with a simple structure, and the cost can be reduced.

In the gear shift control device of the fifth aspect of the invention, the pivot point of the adjustment link is pivotally supported by the fixed member disposed adjacent to the adjustment link. Therefore, the space essential for swinging the adjustment link is utilized for adjustment. Can do link pivots,
Even with the adjusting structure of the above type, the toroidal type continuously variable transmission is not increased in size.

[0022]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 (a), 1 (b) and 2 exemplify a toroidal type continuously variable transmission equipped with a shift control device according to an embodiment of the present invention, and FIG. 1 (a) shows a toroidal type continuously variable transmission. FIG. 2 (b) is a detailed view showing an enlarged main part of the shift control device, and FIG. 2 is a transverse plan view of the toroidal type continuously variable transmission.

First, to explain the toroidal transmission unit, it has an input shaft 20 to which the rotation from an engine (not shown) is transmitted, and this input shaft has a bearing in a transmission case 21 as shown in FIG. It is rotatably supported via 22 and 23. I / O cone disk 2 on the input shaft 20
4, 25 are rotatably supported, and these cone disks are arranged so that the toroidal curved surfaces face each other. A pair of power rollers 26 arranged on both sides of the input shaft 20 sandwiching the input shaft 20 are interposed between the opposite toroidal curved surfaces of the input / output cone disks 24, 25. The following configuration is adopted for clamping.

That is, the loading nut 27 is screwed into the shaft end of the input shaft 20, and the spacer 28 and the disc spring 29 are sequentially interposed between the loading nut 27 and the bearing 23. The disc spring 29 biases the input shaft 20 to the right in FIG. 2 and transmits the biasing force to the input cone disc 24. Therefore, the disc spring 29 is arranged so as to be back-to-back with the input cone disc 24. Drive plate 30 is coupled to the drive plate 30 and the input cone disc 2
The loading cam 31 is interposed between the four. The loading cam 31 further serves to transmit power from the drive plate 30 rotating with the input shaft 20 to the input cone disc 24. During the transmission, thrust corresponding to the transmission torque is generated to generate input thrust. The power roller 26 is pinched between the input cone disk 24 and the output cone disk 25 by urging the power roller 26 toward the output cone disk 25.

An output gear 32 is arranged so as to face the rear surface of the output cone disc 25, and the output gear 32 is engaged with the output cone disc 25 by a key 33 and rotatably supported by the transmission case 21 by a bearing 34. Where the bearing 3
Reference numeral 4 also serves to receive the biasing force and thrust by the above-mentioned disc spring 29.

As shown in FIG. 1, each power roller 26 is rotatably supported by a trunnion 35, and each trunnion has an upper end rotatably and swingably at both ends of an upper link 36 and a lower end. Both ends of the link 37 are rotatably and swingably connected. The upper link 36 and the lower link 37 support the center of the transmission case 21 in a vertically swingable manner so that both trunnions 35 can be vertically moved in synchronization with each other in opposite directions.

A gear shift control device for shifting gears by vertically moving both trunnions 35 in a mutually opposite direction in synchronization will be described below with reference to FIG. Each trunnion 35 is provided with a piston 39 for individually stroking them up and down, and a shift control valve 40 is provided for stroke control of these pistons in mutually opposite directions.
Here, the shift control valve 40 includes a spool type inner valve body 41 and a sleeve type outer valve body 42 slidably fitted to each other, and the outer valve body 42 is slidable on the valve outer casing 43. It is configured by fitting.

A speed change command to the speed change control valve 40 is given from the step motor 44 to the outer valve body 42 via the rack and pinion 45, and the speed change control valve 4 is supplied by this speed change command.
When the outer valve body 42 of 0 is displaced relative to the inner valve body 41 from the neutral position, both trunnions 35 are displaced by fluid pressure in the up and down directions in the figure via the piston 39. To do. As a result, in both power rollers 26, the rotation axis O ₁ is the rotation axis O ₂ of the input / output cone disks 24, 25.
It will be offset from the illustrated position intersecting with
Due to the offset, the power roller 26 is tilted around the swing axis O ₃ orthogonal to its own rotation axis O _{1 by the} swing component force from the input / output cone disks 24, 25, and continuously variable transmission is performed. it can.

A precess cam 46 is connected to the lower end of one of the trunnions 35, and this precess cam controls the vertical movement and tilting of the trunnion 35 and the power roller 26 through a bell crank type speed change link 47. Feedback to the inner valve body 41.

The shift link 47 is the shift control valve 4 in the neutral position.
0, more specifically, it is necessary to adjust the initial position with respect to the inner valve body 41 at the time of assembling. In this example, the speed change link 47 is attached as follows so that this adjustment is possible. That is, the speed change link 47 is pivotally supported on the adjustment link 49 by the pin 48, one end of the adjustment link 49 is pivotally attached to the fixed member 51 by the pin 50, and the other end is engaged with the inner end groove 52a of the adjustment screw 52. To combine. The fixed member 51 is an adjustment link 49.
And is fixed to the valve outer casing 43 with bolts 53,
When engaging the other end of the adjusting link 49 with the inner end groove 52a of the adjusting screw 52, as shown in FIG. 1B, a cylindrical projection protruding laterally from the other end of the adjusting link 49. 49a is provided, and this is inserted into the inner end groove 52a of the adjusting screw 52. The adjusting screw 52 is the transmission case 2
1 and is oil-tightly sealed by a seal ring 54, and a screw nut position with respect to the transmission case 21 can be fixed by a lock nut 55.

The operation of the above embodiment will be described below. The rotation of the input shaft 20 reaches the input cone disk 24 via the drive plate 30 and the loading cam 31 which rotate together with the input shaft 20, and is then transmitted to the output gear 32 via the power roller 26 and the output cone disk 25. Here, the disc spring 29 clamps the power roller 26 between the input and output cone disks 24 and 25 by the set load, thereby enabling the initial transmission upon the above transmission.
The loading cam 31 generates a thrust according to the subsequent transmission torque and the power roller 2 according to the transmission torque.
By pinching 6 between the input / output cone discs 24 and 25, subsequent transmission is enabled.

In shifting control, the step motor 4
4 through the rack and pinion 45 through the shift control valve 40
A shift command is given to the outer valve body 42 of the above. As a result, the outer valve body 42 of the shift control valve 40 is displaced from the neutral position relative to the inner valve body 41, and the two trunnions 35 and the power roller 26 are fluid-fluidized through the piston 39 to the position shown in FIG.
Displace in the vertical direction of (a), but in opposite directions. Thus, both power rollers 26 are offset from the illustrated position where the axis of rotation O ₁ intersects the axes of rotation O ₂ of the input / output cone disks 24, 25,
With the swing component force from 25, it is tilted around the swing axis O ₃ orthogonal to the own rotation axis O ₁ . This tilt is caused by the power roller 26 with respect to the input / output cone disks 24, 25.
The diameter of the friction engagement circle is continuously changed, and as a result, continuously variable transmission can be performed.

When the above shift command is achieved by such a continuously variable shift, the inner valve body 41 of the shift control valve 40 which feeds back the offset and tilt of the power roller 26 via the recess cam 46 and the shift link 47 is used. ,
Following the displacement of the outer valve body 42, it returns to the initial neutral position relatively. As a result, the two trunnions 35 and the power roller 26 are hydraulically moved to the original position of FIG. 1A via the piston 39, that is, the position where the power roller rotation axis O ₁ intersects the input / output cone disk rotation axis O _2. It is possible to return and maintain the achievement state of the shift command.

Here, the speed change link 47 is connected to the speed change control valve 40.
When adjusting the position, the lock nut 55 is loosened to decrease the screwing amount of the adjusting screw 52 from the screwing position shown in FIG. 3A as indicated by α in FIG. It is increased as indicated by β in FIG. As a result, the pivot point 48 of the speed change link 47 is rotationally displaced around the pin 50 as shown by γ and δ, and the position of the speed change link 47 can be adjusted with respect to the speed change control valve 40 while being in contact with the precess cam 46. . After the adjustment, the lock nut 55 is tightened to fix the adjustment position.

By the way, in the above adjustment, the adjusting screw 52
Need not be removed from the transmission case 21, and the adjustment work can be performed from the outside of the transmission case 21. Therefore, up to the level of the adjusting screw 52, the transmission case 21
If the hydraulic oil is present inside, it is possible to prevent the hydraulic oil from leaking out during the adjustment work, and the workability of the adjustment work can be greatly improved.

As shown in FIG. 3A, the arm length L ₁ from the pivot pin 50 of the adjustment link 49 to the cylindrical projection 49a, which is the force point of the adjustment link 49, is adjusted from the pivot pin 50 of the adjustment link 49 to the arm length L _1. When the arm length L ₂ reaching the speed change link pivot pin 48 is made longer, the adjustment sensitivity is made dull by the lever ratio represented by the ratio of these arm lengths, so that even when fine adjustment is required, this can be easily done. Can be dealt with
Further, by changing the lever ratio, the adjustment sensitivity can be arbitrarily determined according to the demand.

Further, as in the configuration of this example, the shift control valve 40
And the outer valve housing 4 to which the recess cam 46 is attached
When the adjustment link 49 is pivotally supported by the pin 50 with respect to 3, the relative position of the adjustment link 49 with respect to the speed change control valve 40 and the recess cam 46, and thus the relative position of the speed change link 47, is convenient.

When the adjusting link 49 is engaged with the inner end groove 52a of the adjusting screw 52, a cylindrical projection 49a is provided at the corresponding end of the adjusting link 49 so as to project in the lateral direction. When engaging with the groove 52a, the adjustment screw 52 and the adjustment link 49 can be engaged with a simple structure, and the cost can be reduced.

In addition, when the fixed member 51, which is indispensable for pivotally supporting the adjustment link 49, is arranged adjacent to the adjustment link 49 as in this example, the space essential for the swinging of the adjustment link 49 is used for adjustment. The link can be pivotally supported, and even if the above-mentioned special speed change link adjusting structure is used, the toroidal type continuously variable transmission is not increased in size.

In the above-mentioned example, the adjustment link 49 is aimed at the above-mentioned aim, and the shift control valve 40 and the precess cam 46.
Although the pin 50 is used to pivotally support the valve outer casing 43 to which is attached, as shown in FIG.
The adjustment link 49 may be pivotally supported with respect to the transmission case 21 as shown in (a) and (b). In this case, the fixed member 51, which should pivotally support the adjustment link 49, is fastened to the transmission case 21 with the bolt 56.

[0041]

As described above, according to the first aspect of the present invention, there is provided a transmission control device for a toroidal type continuously variable transmission, wherein a speed change link is pivotally supported on an adjustment link, and the power point of the adjustment link is set at the transmission. Since the adjustment screw that is oil-tightly sealed from the case and protrudes to the outside is engaged, it is possible to perform all the position adjustment work of the transmission link with respect to the transmission control valve from the outside of the transmission case. In addition, the hydraulic oil can be prevented from leaking out of the transmission case, and the workability of the adjustment work can be improved.

According to a second aspect of the present invention, as described in claim 2, the arm length from the pivot point of the adjustment link to the force point is longer than the arm length from the pivot point to the transmission link connection point. Therefore, it is possible to reduce the adjustment sensitivity by the lever ratio represented by the ratio of these arm lengths, and to deal with this even when subtle adjustment is required.Also, by changing the lever ratio, adjustment can be made. The sensitivity can be arbitrarily determined according to the requirements, and the additional advantage that it can be applied to any toroidal type continuously variable transmission can be obtained.

Further, in the shift control device of the third invention, as described in claim 3, the pivot point of the adjustment link is pivotally supported with respect to the valve outer casing to which the outer valve body of the shift control valve is fitted. From
Since the shift control valve and the recess cam are positioned with respect to the valve outer casing, the relative position of the adjustment link, and thus the relative position of the shift link, can be made accurate with respect to these.

According to a fourth aspect of the present invention, the gear shift control device is provided with a cylindrical projection so as to project laterally at the force point of the adjusting link, and the cylindrical projection is provided in the inner end groove of the adjusting screw. Since they are engaged, the adjustment screw and the adjustment link can be engaged with each other with a simple structure, and the cost can be reduced.

According to a fifth aspect of the present invention, there is provided a gear change control device.
As described above, since the pivot point of the adjustment link is pivoted on the fixed member disposed adjacent to the adjustment link, the adjustment link is pivoted using the space indispensable for swinging the adjustment link. Even if the above-mentioned peculiar speed change link position adjusting structure is adopted, the toroidal type continuously variable transmission is not increased in size.

[Brief description of drawings]

FIG. 1 (a) is a vertical cross-sectional front view of a toroidal-type continuously variable transmission equipped with a shift control device according to an embodiment of the present invention,
FIG. 6B is an enlarged detailed view showing a part of the gearshift link mounting portion in the same example, which is cut away.

FIG. 2 is a cross-sectional plan view of the toroidal type continuously variable transmission in the same example.

FIG. 3 is an operation explanatory diagram relating to the position adjusting mechanism of the speed change link in the example.

FIG. 4A is a vertical sectional front view of a toroidal type continuously variable transmission equipped with a shift control device according to another example of the present invention, and FIG. FIG.

FIG. 5 is a vertical sectional front view of a toroidal-type continuously variable transmission showing a conventional shift control device.

[Explanation of symbols]

 20 Input Shaft 21 Transmission Case 24 Input Cone Disc 25 Output Cone Disc 26 Power Roller 30 Drive Plate 31 Loading Cam 35 Trunnion 36 Upper Link 37 Lower Link 39 Piston 40 Shift Control Valve 41 Inner Valve Body 42 Outer Valve Body 43 Outer Casing 44 Step motor 45 Rack and pinion 46 Precess cam 47 Shift link 48 Shift link pivot pin 49 Adjustment link 49a Cylindrical protrusion 50 Adjustment link pivot pin 51 Fixed member 52 Adjustment screw 52a Inner groove 54 Seal ring 55 Lock nut

Claims (5)

[Claims] 1. An input / output cone disk arranged coaxially,
It has a toroidal transmission unit consisting of a power roller that transfers power by frictional engagement between these input and output cone discs, and by displacing the inner and outer valve bodies of the shift control valve from a neutral position relatively by a shift command, The power roller is offset by fluid pressure from the position where the rotation axis intersects with the rotation axis of the input / output cone disc, and the offset causes the component force from the input / output cone disc to cause the power roller to go perpendicular to its own rotation axis. By performing tilting around the swing axis, continuously variable gear shifting is performed, and when the gear shifting command is achieved by the continuously variable gear shifting, the offset and tilting of the power roller are controlled via the precess cam and the gear shifting link. Feedback to the valve to relatively return the inner and outer valve elements to the neutral position to achieve the shift command achievement state. In a toroidal type continuously variable transmission having a transmission control device for maintaining the above, the transmission link is pivotally supported on an adjustment link, and the force point of the adjustment link is oil-tightly sealed from the transmission case and protrudes to the outside. A gear shift control device for a toroidal type continuously variable transmission, characterized in that the gear shift control device is engaged with the adjusted screw. 2. The toroidal type continuously variable transmission according to claim 1, wherein the arm length from the pivot point of the adjustment link to the power point is longer than the arm length from the pivot point to the shift link connection point. Gear shift control device. 3. The toroidal type no-body according to claim 1 or 2, wherein a pivot point of the adjustment link is pivotally supported with respect to a valve outer casing to which an outer valve body of the shift control valve is fitted. Gear shift control device for a stepped transmission. 4. The cylindrical projection according to claim 1, wherein a cylindrical projection is provided at a force point of the adjustment link so as to project laterally, and the cylindrical projection is engaged with an inner end groove of the adjustment screw. A gear shift control device for a toroidal type continuously variable transmission characterized by the above. 5. The toroidal type continuously variable transmission according to claim 1, wherein a pivot point of the adjustment link is pivotally supported by a fixed member arranged adjacent to the adjustment link. Shift control device.