JP6413377B2 - Toroidal continuously variable transmission - Google Patents

Description

  The present invention relates to an improvement in a toroidal continuously variable transmission that is used as an automatic transmission for automobiles or as a transmission for adjusting the operating speed of various industrial machines such as pumps.

  The use of a toroidal type continuously variable transmission as an automobile transmission is described in many publications such as Patent Documents 1 to 3 and is partly implemented, and is well known. Also, a structure in which a toroidal type continuously variable transmission and a planetary gear mechanism are combined to widen the adjustment range of the gear ratio is described in many publications such as Patent Document 4 and has been widely known. 1 and 2 show an example of a conventional structure of a toroidal type continuously variable transmission that can be used as such a continuously variable transmission. In the case of this example of the conventional structure, a pair of input side disks 2a and 2b are arranged around both ends of the rotating shaft 1, and the ball splines 3 and 3 are placed in a state where the inner side surfaces, each of which is a toroidal curved surface, face each other. The cylindrical member 4 is supported around the intermediate portion of the rotary shaft 1 so as to be capable of relative rotation with respect to the rotary shaft 1. A gear 5 is fixed to the outer peripheral surface of the cylindrical member 4 at the axially central portion, and a pair of output side disks 6 and 6 are connected to the axially opposite ends by spline engagement. Supports the rotation synchronized with. Further, in this state, the inner side surfaces of the output side disks 6 and 6, each of which is a toroidal curved surface, are opposed to the inner side surfaces of the input side disks 2 a and 2 b.

  Further, a plurality of power rollers 7 and 7 each having a spherical convex surface are sandwiched between the input disks 2a and 2b and the output disks 6 and 6. The power rollers 7 and 7 are respectively connected to the inner surfaces of the trunnions 8 and 8 via support shafts 9 and 9 having a base half portion and a tip half portion eccentric, and a plurality of rolling bearings. , 9 and the rotation of the first half of the support shaft 9 and a slight swing displacement about the base half of each of the support shafts 9 and 9 are supported. The trunnions 8 and 8 are freely supported by swinging displacements about the tilting shafts 10 and 10 that are twisted with respect to the central axes of the disks 2a, 2b, and 6, respectively.

  During operation of the toroidal-type continuously variable transmission as described above, one input side disk 2 a (left side in FIG. 1) is rotationally driven by the drive shaft 11 via the pressing device 12. As such a pressing device, a loading cam type or a hydraulic pressing device can be used. In any case, the pair of input side disks 2a, 2b supported at both axial ends of the rotating shaft 1 rotate synchronously while being pressed in directions approaching each other. Then, this rotation is transmitted to the output side disks 6 and 6 through the power rollers 7 and 7 and is taken out from the gear 5. When changing the gear ratio between the rotary shaft 1 and the gear 5, the trunnions 8 and 8 are displaced in the axial direction of the tilt shafts 10 and 10 by hydraulic actuators 13 and 13, respectively. As a result, the direction of the tangential force acting on the rolling contact portion (traction portion) between the peripheral surface of each of the power rollers 7 and 7 and the inner surface of each of the disks 2a, 2b and 6 changes (rolling contact). Side slip occurs in the part). As the force changes, the trunnions 8 and 8 swing around their own tilting shafts 10 and 10, and the peripheral surfaces of the power rollers 7 and 7 and the disks 2a, The contact position with the inner surface of 2b, 6 changes. The peripheral surfaces of the power rollers 7 and 7 are formed as radially outer portions on the inner side surfaces of the input side disks 2a and 2b and radially inward portions on the inner side surfaces of the output side disks 6 and 6. If it is brought into rolling contact, the gear ratio between the rotary shaft 1 and the gear 5 is increased. On the other hand, the peripheral surfaces of the power rollers 7 and 7 are arranged radially inwardly of the inner side surfaces of the input side disks 2a and 2b and the radial direction of the inner side surfaces of the output side disks 6 and 6. If it is brought into rolling contact with the outer portion, the gear ratio between the rotary shaft 1 and the gear 5 becomes the deceleration side.

  As described above, the mechanism for adjusting the transmission ratio of the toroidal-type continuously variable transmission to a desired value and maintaining the adjusted value will be described based on the description in Patent Document 1. As shown in FIG. 3, this mechanism includes a transmission ratio control valve 14, a stepping motor 15, and a recess cam 16. Among them, the transmission ratio control valve 14 is a combination of a spool 17 and a sleeve 18 so as to allow relative displacement in the axial direction. Based on the relative displacement between the spool 17 and the sleeve 18, the hydraulic power source 19, The supply / discharge state of the actuator 13 with the hydraulic chambers 20a and 20b is switched. The spool 17 and the sleeve 18 are relatively displaced by the movement of one of the trunnions 8 and 8 and the stepping motor 15. In the illustrated example, the movement of any one of the trunnions 8, that is, the axial displacement of each of the tilt shafts 10 and 10 and the swing displacement about each of the tilt shafts 10 and 10 are described above. The spool 17 is transmitted to the spool 17 via the recess cam 16 and the link arm 21 to displace the spool 17 in the axial direction, and the sleeve 18 is displaced in the axial direction by the stepping motor 15.

  When adjusting the gear ratio of the toroidal continuously variable transmission, the sleeve 18 is displaced to a predetermined position by the stepping motor 15 and the gear ratio control valve 14 is opened in a predetermined direction. Then, pressure oil is supplied to and discharged from the hydraulic chambers 20a, 20b of the actuators 13, 13 attached to the trunnions 8, 8 in a predetermined direction, and the trunnions 8, 8 are supplied by the actuators 13, 13. Are displaced in the axial direction of each of the tilt axes 10 and 10, respectively. As a result, the traction portions related to the power rollers 7 and 7 supported by the trunnions 8 and 8 are in a neutral position (the center of the traction portions includes the central axis of the disks 2a, 2b, and 6). The gear ratio begins to change in a manner that deviates from a state that exists on a virtual plane orthogonal to a virtual straight line connecting the central axes of the tilt axes 10 and 10. In this way, at the moment when each of these traction portions deviates from the neutral position and the transmission ratio starts to change, the open / close state of the transmission ratio control valve 14 is changed according to the axial displacement of each of the trunnions 8, 8. Switching to a direction opposite to the predetermined direction. Therefore, the trunnions 8 and 8 start to move (return) toward the neutral position in the axial direction from the moment when the swing displacement starts to be started for shifting. In the state where the gear ratio has reached the desired value, the traction portions return to the neutral position, and at the same time, the gear ratio control valve 14 is closed by the action of the recess cam 16 and the link arm 21. It is done. As a result, the transmission ratio of the toroidal type continuously variable transmission is maintained at the desired value. In order to increase the amount of deviation of each traction portion from the neutral position in order to increase the speed of change (speed) of the gear ratio of the toroidal-type continuously variable transmission, Increase the amount of displacement. Conversely, in order to reduce the adjustment speed, the displacement of the sleeve 18 by the stepping motor 15 is reduced in order to reduce the amount of displacement of the traction portions from the neutral position. The actuators 13 and 13 are connected to the trunnion shafts 10 and 10 which are applied to the trunnions 8 and 8 based on the power transmission while the toroidal continuously variable transmission transmits power. The axial thrust load (the traction force called “2Ft” in the technical field of toroidal type continuously variable transmissions) is supported.

  In the case of the toroidal type continuously variable transmission as described above, at the time of torque transmission in each of the traction parts, the pressing device 12 presses the input side disks 2a and 2b toward each other, Appropriate surface pressure (normal force Fc) is applied. Then, traction oil is continuously supplied to the traction portions between the peripheral surfaces of the power rollers 7 and 7 and the inner surfaces of the disks 2a, 2b and 6, and the traction oil is supplied to the traction portions. A thin film is formed. That is, in each of these traction portions, there is a contact ellipse of about 4 × 10 mm, for example. Then, a high surface pressure of 3.5 GPa or more is applied to the central portion of the contact ellipse when transmitting large power exceeding 50 kW, for example. In each traction section where such high surface pressure is applied, the amount of heat generated is also considerable, so that each traction section is cooled and this traction oil is supplied to secure a thin film of traction oil in each traction section. It is necessary to continue. For this reason, in the case of the conventional structure, traction oil absorbed from an oil reservoir (drain) and discharged from an oil supply pump can be sprayed from the nozzle hole to each traction portion through an oil supply passage.

The toroidal type continuously variable transmission as described above has room for improvement in terms of ensuring durability and improving transmission efficiency. This point will be described with reference to FIG. 4 in addition to FIGS.
During normal operation in which the toroidal-type continuously variable transmission transmits torque without performing a speed change operation, the traction force 2Ft (Ft for each traction portion) is applied to the power rollers 7 and 7, respectively. As indicated by the arrow a, the disk 2a, 2b, 6 is added in the rotational direction. The magnitude of the transmission traction force 2Ft to be transmitted between the disks 2a, 2b, 6 increases as the torque transmitted between the disks 2a, 2b, 6 increases (the arrow a is longer). Become. The maximum value (limit traction force) F _max of the traction force that can be transmitted by each of these traction parts during the normal operation is the normal force Fc and the traction coefficient μ _t (tangential force / normal line) of each of these traction parts. Power). This traction coefficient μ _t is set in advance based on the performance of the traction oil, such as the type of traction oil.

  On the other hand, the trunnions 8 and 8 that support the power rollers 7 and 7 are moved to the respective tilts in order to perform a shift while the torque is being transmitted between the disks 2a, 2b, and 6. When the shafts 10 and 10 are displaced in the axial direction, the power rollers 7 and 7 are placed on the trunnions 8 and 8 around the tilt shafts 10 and 10 as indicated by arrows b in FIG. The side slip force Fs in the direction of swinging is applied. Therefore, when shifting is performed while torque is transmitted between the disks 2a, 2b, 6, the traction portions are connected to the traction force Ft and the side slip force Fs for each traction portion. The resultant traction force Fr, which is the resultant force, acts in a direction inclined with respect to the rotational direction of the disks 2a, 2b, 6 as indicated by an arrow c in FIG. The magnitude of the combined traction force Fr (the length of the arrow c) increases the side slip force Fs (increases the length of the arrow b) in order to increase the shift speed, as is apparent from FIG. It gets bigger (longer).

Here, as the transmission speed of the toroidal-type continuously variable transmission increases, the amount of heat generated due to side slip in each traction section increases, and the oil temperature of the traction oil in each traction section increases. . The traction coefficient μ _t becomes smaller as the oil temperature in each of the traction parts becomes higher at 20 ° C. or higher, which is the oil temperature at which this traction oil is normally used (when the transmission torque is the same, (The normal force Fc required to transmit torque increases without causing gross slip in the traction section). Accordingly, when the speed change speed is increased, the traction coefficient μ _t in each traction section is decreased, and the limit traction force F _max is decreased as indicated by an arrow d in FIG. And when the magnitude | size of the said synthetic traction force Fr becomes larger than this limit traction force _Fmax (refer the circle R of FIG. 4), it will become easy to generate | occur | produce gross slip in each said traction part. When such gross slip occurs, the peripheral surfaces of the power rollers 7 and 7 and the inner surfaces of the disks 2a, 2b, and 6 are in direct rolling contact with each other without the traction oil thin film interposed therebetween. (Metallic contact occurs), causing significant wear on each of the surfaces, thereby significantly reducing the durability of the toroidal continuously variable transmission.

In order to prevent such a gross slip, it is conceivable to increase the normal force Fc based on the pressing force by increasing the pressing force generated by the pressing device 12. Accordingly, if the limit traction force F _max (radius of the circle R in FIG. 4) can be secured (maintained), a margin (slip margin) δ which is a difference between the magnitude of the limit traction force F _max and the combined traction force Fr. _It is possible to sufficiently secure _f, and it is possible to prevent the occurrence of a gloss slip that causes a decrease in durability of the toroidal-type continuously variable transmission. However, if the pressure receiving area of the pressing device 12 is increased in order to increase the pressing force generated by the pressing device 12, the toroidal continuously variable transmission including the pressing device 12 is enlarged. On the other hand, when a hydraulic pressure device is used, if the hydraulic pressure introduced into the hydraulic chamber constituting the pressure device is increased without increasing the size of the pressure device, the pump is driven to generate the hydraulic pressure. As a result, the power (pump loss) required for the transmission increases, and not only the transmission efficiency of the entire toroidal-type continuously variable transmission decreases, but also the rolling resistance of each traction section increases.

Also, by increasing the amount of traction oil supplied to each traction section (the amount of traction oil is set to the required maximum amount), the temperature increase of the traction oil existing in each traction section is suppressed, and the traction oil it is also conceivable to suppress a reduction in the traction coefficient μ _t. However, if the supply amount of traction oil is simply increased, the amount of traction oil supplied to each traction section becomes excessive when the temperature rise of the traction oil is relatively small. Considering only the securing of reliability, such as prevention of the occurrence of gloss slip in each of these traction sections, there is no particular problem that the amount of the traction oil becomes excessive. However, when the amount of the traction oil becomes excessive, the stirring resistance (drag loss) is increased, and the transmission efficiency of the toroidal continuously variable transmission as a whole is lowered.

  In Patent Document 2, a flow rate adjusting valve is provided in the middle of an oil supply passage that connects an oil supply pump and a nozzle hole, and the amount of power that the toroidal continuously variable transmission transmits the amount of traction oil supplied to the traction section. A structure that can be adjusted accordingly is described. Further, in Patent Document 3, by providing an opening in a trunnion connecting member (restricting member), the amount of traction oil discharged from the nozzle holes (the amount reached) to the traction portion is determined between the disks. The structure which can be adjusted according to the gear ratio is described. However, even in the structures described in both Patent Documents 2 to 3, the transmission ratio of the toroidal type continuously variable transmission fluctuates abruptly (the transmission speed is fast), and the amount of heat generated in each traction section increases. If the oil temperature of the traction oil in each of these traction parts rises accordingly, the amount of traction oil existing in each of these traction parts may be insufficient, and gloss slip may easily occur in each of these traction parts. There is.

JP 2006-283800 A JP 2001-132808 A JP 2005-140149 A JP 2009-30749 A

  The present invention has been invented to realize a structure of a toroidal continuously variable transmission that prevents the occurrence of gross slip in the traction section and suppresses a decrease in transmission efficiency in view of the circumstances as described above. .

Each of the toroidal type continuously variable transmissions of the present invention includes at least a pair of disks, a plurality of support members, the same number of power rollers as each of the support members, and a lubricating device.
Of these, the disks are concentrically supported and freely rotatable relative to each other in a state in which the respective one side surfaces in the axial direction, each of which is a toroidal curved surface having an arc cross section, are opposed to each other.
In addition, each of the support members has a plurality of swings with respect to the axial direction, and each of the support members is pivoted about a tilt shaft that is twisted with respect to the central axis of each disk. Dynamic displacement is provided freely.
Each power roller is rotatably supported by each support member, and has a spherical convex surface abutting against one axial side surface of each disk.
The lubricating device supplies traction oil to a traction portion that is a rolling contact portion between one axial side surface of each disk and the peripheral surface of each power roller.

In particular, at the toroidal type continuously variable transmission according to claim 1, wherein the lubricating device, while said that by changing the gear ratio between each disc between the transmission ratio between the respective disks together It has a function of adjusting the amount of traction oil discharged toward each of the traction sections according to the change speed of the traction.

When the toroidal continuously variable transmission according to the first aspect described above is implemented, specifically, as in the invention according to the second aspect, the adjustment of the transmission ratio between the disks is performed as described above. Each of the discs is displaced by displacing each of the support members in the axial direction of each of the tilting shafts by an actuator provided for each of the support members, and each of the support members is oscillated and displaced about the respective tilting shafts The gear ratio between them is adjusted. And while the lubricating device is changing the gear ratio between these disks, the displacement speed of at least one of the support members in the axial direction of the tilt shafts It is assumed that the amount of traction oil discharged toward each of the traction units is adjusted according to (change amount per unit time). Alternatively, the amount of traction discharged toward each of the traction portions can be adjusted according to the amount of displacement of the at least any one support member in the axial direction of each tilt axis.
Alternatively, the value of the output signal of the rotational speed sensor for detecting the rotational speed of each disk or the swing of each of these support members centered on each of the tilt axes detected by the angle sensor attached to each of the support members. You may comprise so that the quantity of the traction oil supplied to each said traction part may be adjusted according to the change speed (shift speed) of the gear ratio between each said disk calculated based on the moving angle.

Further, in the toroidal type continuously variable transmission according to claim 3, each of the traction sections is arranged immediately after the gear shift command is issued only on the condition that the gear shift command is issued. It has a function of increasing the amount of traction oil discharged toward the vehicle.
The inventions described in claims 1 and 2 and the invention described in claim 3 can be carried out simultaneously.

  When the toroidal type continuously variable transmission of the present invention as described above is implemented, the lubricating device, for example, an oil supply pump for sending out the traction oil, and discharges the traction oil to the traction portions. For this purpose, an oil supply passage connecting the oil supply pump and the nozzle hole, and a flow rate adjusting valve provided in the oil supply passage. The amount of traction oil discharged from the nozzle hole can be adjusted by adjusting the opening of the flow rate adjusting valve. Or you may comprise so that the quantity of the traction oil discharged from a nozzle hole may be adjusted by adjusting the hydraulic pressure in an oil supply channel | path.

According to the toroidal-type continuously variable transmission of the present invention configured as described above, it is possible to suppress a decrease in transmission efficiency while preventing the occurrence of gross slip in the traction section.
That is, according to the present invention , the amount of traction oil discharged toward each traction portion can be increased while changing the gear ratio between the disks. Therefore, the even when the transmission ratio of the toroidal type continuously variable transmission has suddenly change, suppressed an increase in the temperature of the traction oil present in the respective traction unit, the traction coefficient mu _t of the traction oil drops (the limit Traction force is reduced). As a result, during the speed change operation, it is possible to prevent the occurrence of gross slip in each traction section, and to ensure the durability of the toroidal continuously variable transmission. Further, it is possible to prevent the traction oil supplied to each traction section from becoming excessive during normal operation in which no speed change operation is performed, and it is possible to prevent the transmission efficiency of the toroidal type continuously variable transmission from being lowered.
According to the third aspect of the present invention, the traction oil can be sufficiently supplied to the traction sections immediately after the start of the shifting operation of the toroidal continuously variable transmission.

Sectional drawing which shows one example of the toroidal type continuously variable transmission used as the object of this invention. XX sectional drawing of FIG. FIG. 3 is a schematic cross-sectional view of a hydraulic control device portion for gear ratio control. The schematic diagram for demonstrating why a slip is easy to generate | occur | produce in each traction part when gear ratio adjustment is performed at high speed.

  Hereinafter, three examples of the embodiment of the present invention will be described. The feature of the toroidal type continuously variable transmission of the present invention is that the amount of traction oil discharged toward the traction portion which is a rolling contact portion between the peripheral surface of each power roller and the inner side surface of each disk is changed to a variable state or By making the adjustment possible based on the output of the gear shift command, it is possible to prevent a reduction in transmission efficiency while preventing the occurrence of gross slip in each traction section. The basic structure of the toroidal type continuously variable transmission shown in the drawing is the same as that of conventionally known toroidal type continuously variable transmissions, including the structure shown in FIGS. The illustration and description of the specific structure are omitted, and the characteristic part of each example of the embodiment of the present invention will be described below. In addition, about the code | symbol of a toroidal type continuously variable transmission, what was described in above-mentioned FIGS. 1-3 is used.

尚、この（１）式中、ｃ_１、ｃ_２は、それぞれ流量係数を表し、予め実験や計算により求められる。この様な（１）式から明らかな通り、前記各トラクション部へのトラクションオイルの供給量は、前記各ディスク２ａ、２ｂ、６同士の間で伝達する動力Ｐが大きい程、又、変速速度ｖが大きい（速い）程多くなる。 [First example of embodiment]
A first example of an embodiment of the present invention corresponding to claims 1 and 2 will be described. In the case of the toroidal-type continuously variable transmission of this example, similarly to the structure described in the above-mentioned Patent Document 2, the oil supply pump for sending out the traction oil and the traction oil are supplied to the circumference of each power roller 7, 7. A flow rate adjusting valve is provided in the middle of the oil supply passage connecting the surface and the nozzle hole for discharging to the rolling contact portion (traction portion) of each disk 2a, 2b, 6, and the traction oil discharged toward each of these traction portions The amount is adjustable. In the case of this example, the amount of traction oil discharged from the nozzle hole is added to the magnitude of the power (claw torque × rotational speed) transmitted between the disks 2a, 2b, 6 and these disks. It can be adjusted according to the changing speed (shift speed) of the speed ratio between 2a, 2b, and 6 (the speed ratio of the toroidal-type continuously variable transmission). That is, the amount of traction oil discharged from the nozzle hole (≈the amount of traction oil supplied to each traction portion) Q is P, which is the power transmitted between the disks 2a, 2b, 6 and the speed of change. Assuming v, it is expressed by the following equation (1).

In the equation (1), c ₁ and c ₂ each represent a flow coefficient, and are obtained in advance by experiments and calculations. As is apparent from the equation (1), the amount of traction oil supplied to each traction section increases as the power P transmitted between the disks 2a, 2b, 6 increases, and the shift speed v increases. The larger (faster) the more.

The power P is obtained from, for example, the rotational speed (rotational speed) of any one of the disks 2a, 2b, 6 and the accelerator opening. That is, the input torque to the input side disks 2a and 2b is obtained from the rotational speed of any one of these disks and the accelerator opening, and the power is calculated from the input torque thus obtained and the rotational speed of any one of the disks. Find P. Alternatively, the input torque to both the input side disks 2a, 2b is obtained based on the hydraulic pressure difference (differential pressure) between the hydraulic chambers 20a, 20b of the actuators 13, 13 provided for each trunnion 8, 8, The power P may be obtained from the input torque and the rotational speed of any one of the disks.
In the case of this example, the shift speed v is determined by the inclination of any one of the trunnions 8, 8 when the trunnions 8, 8 are displaced (returned) toward the neutral position. It is obtained by measuring the displacement speed (displacement amount per unit time) in the axial direction of the rolling shafts 10 and 10. Note that this displacement speed can be measured by a non-contact displacement sensor or the like in which the detection portion is opposed to the axial end surface of any one of the trunnions 8.
However, the shift speed v is calculated based on the number of rotations of the disks 2a, 2b, 6 or by the angle sensors attached to the rods 22, 22 of the trunnions 8, 8, respectively. Alternatively, it may be obtained by detecting the swing angle of each of the trunnions 8 and 8 centered on 10 central axes.

According to the toroidal type continuously variable transmission of the present example as described above, it is possible to suppress a decrease in transmission efficiency while preventing the occurrence of gross slip in each traction section.
That is, since the amount of traction oil discharged toward each traction section can be adjusted according to the operating status of the toroidal type continuously variable transmission (power and transmission speed transmitted by the toroidal type continuously variable transmission), A sufficient amount of traction oil is supplied to each traction section to prevent the occurrence of gross slip in each traction section, while the transmission efficiency of the toroidal type continuously variable transmission is reduced due to excessive supply of traction oil. Can be prevented.

In particular, in the case of the toroidal continuously variable transmission of this example, the amount of traction oil discharged toward the traction portions can be adjusted according to the shift speed of the toroidal continuously variable transmission. For this reason, even when the gear ratio of this toroidal type continuously variable transmission fluctuates suddenly (the gear shift speed is fast), a sufficient amount of traction oil is supplied to each traction section, and the traction existing in each traction section The oil can be sufficiently cooled. Accordingly, it is possible to secure the magnitude of the limit traction force F _max by suppressing the decrease in the traction coefficient μ _t of the traction oil in each of these traction portions (the decrease in the limit traction force F _max can be suppressed). A margin (slip margin) δ _f that is the difference between the limit traction force F _max and the combined traction force Fr that is the resultant force of the transmission traction force Ft and the side slip force Fs can be sufficiently secured (maintained). . As a result, during the shifting operation of the toroidal type continuously variable transmission, it is possible to prevent the occurrence of gross slip in each of the traction sections, and to ensure the durability of the toroidal type continuously variable transmission. Further, in the case of this example, the traction oil supplied to each traction section becomes excessive during normal operation when the toroidal type continuously variable transmission does not perform the shifting operation or when the shifting operation is performed slowly. Can be prevented. For this reason, it is possible to suppress the agitation resistance of the traction oil from increasing suddenly in each of these traction portions, and to prevent the transmission efficiency of the toroidal type continuously variable transmission from being lowered.

[Second Example of Embodiment]
A second example of the embodiment of the present invention corresponding to claim 1 will be described. The toroidal-type continuously variable transmission of this example adds the amount of traction oil discharged toward each traction section to the magnitude of the power transmitted between each disk 2a, 2b, 6 and at both ends. Adjustment is possible according to the amount of displacement of each trunnion 8, 8 in the axial direction of the provided tilting shafts 10, 10. That is, as the displacement amount of each trunnion 8, 8 increases, the side slip force Fs in the direction of swinging each trunnion 8, 8 about the tilt shafts 10, 10 increases, and the toroidal type The speed of the continuously variable transmission is increased. Therefore, in the case of the present example, the amount of traction oil discharged toward each traction portion increases as the displacement amount of each trunnion 8, 8 increases.

尚、この（２）式中、ｃ_１、ｃ_３は、それぞれ流量係数を表し、予め実験や計算により求められる。尚、本例を実施する場合、前記動力Ｐ及び前記各トラニオン８、８の軸方向変位量Δｄに加え、前記トロイダル型無段変速機の変速比Ｉに応じて前記トラクションオイルの吐出量Ｑを調節する事もできる。この場合、この吐出量Ｑは、次の（３）式で表される。

（３）式中、ｃ_１’、ｃ_３’、ｃ_４は、それぞれ流量係数を表す。
その他の部分の構成及び作用は、上述した実施の形態の第１例と同様である。 The amount Q of traction oil discharged toward each traction section is expressed by the following equation (2), where P is the power and Δd is the amount of axial displacement of each trunnion 8, 8.

In the equation (2), c ₁ and c ₃ each represent a flow coefficient and are obtained in advance by experiments and calculations. In the case of carrying out this example, in addition to the power P and the axial displacement amount Δd of each trunnion 8, 8, the discharge amount Q of the traction oil is set according to the gear ratio I of the toroidal continuously variable transmission. You can also adjust. In this case, the discharge amount Q is expressed by the following equation (3).

In _{(3), c 1 ', c 3'} , c 4 each represents a flow coefficient.
The configuration and operation of the other parts are the same as in the first example of the embodiment described above.

[Third example of embodiment]
A third example of the embodiment of the present invention corresponding to claim 3 will be described. The toroidal-type continuously variable transmission of the present example controls the amount of traction oil discharged toward each traction section when a shift command is issued from the controller for controlling the stepping motor 15 to the stepping motor 15. I try to increase it. That is, the side slip force applied to each of these traction portions becomes the maximum immediately after the start of the shifting operation. As the side slip force increases, the amount of heat generated in each traction section also increases considerably, and gloss slip is likely to occur in each traction section. Such a tendency is caused by a toroidal equipped with a manual transmission mode (so-called manual mode) in which the transmission ratio between the disks 2a, 2b, 6 can be adjusted to a preset value based on manual operation of the transmission ratio changeover switch. In the type continuously variable transmission, this is particularly noticeable when the gear ratio changeover switch is operated, when sudden acceleration is performed based on kickdown, or when sudden deceleration is performed by depressing the brake pedal strongly. Therefore, in the case of this example, when a shift command is issued, the amount of traction oil discharged toward each traction section is increased by a predetermined time (until the shift operation is completed).

この（４）式中、ｃ_１、ｃ_５は、それぞれ流量係数を表し、予め実験や計算により求められる。尚、これら両流量係数ｃ_１、ｃ_５のうち、前記値ｆに関する流量係数ｃ_５を、変速動作開始直前の変速比に応じて変化させる事もできる。 The discharge amount Q of the traction oil is expressed by the following equation (4), where P is the power and f is a value (variable) indicating whether or not the gear ratio switch is operated. The value f is substituted by 1 when the shift command is issued, and is substituted by 0 when the operation is not performed.

In this equation (4), c ₁ and c ₅ each represent a flow coefficient, and are obtained in advance through experiments and calculations. Of these flow coefficients c ₁ and c ₅ , the flow coefficient c ₅ related to the value f can be changed according to the gear ratio immediately before the start of the shift operation.

  According to this example as described above, traction oil can be sufficiently supplied to each traction section immediately after the start of the shifting operation of the toroidal type continuously variable transmission. That is, for example, as in the first example of the above-described embodiment, the traction oil discharged toward each traction portion according to the displacement speed of each trunnion 8, 8 with respect to the axial direction of each tilt shaft 10, 10. In the case of a structure in which the amount is adjusted, in order to detect the displacement speed with a required accuracy, it is necessary to displace the trunnions 8 and 8 in the axial direction of the tilt shafts 10 and 10 by a predetermined amount or more. For this reason, there is a slight delay before the displacement speed is calculated. Furthermore, after calculating the amount of traction oil required by the controller, etc., the valve opening pressure of the flow rate adjustment valve is adjusted to a desired value, and a predetermined amount of traction oil is discharged toward each traction section. There may be a delay. Therefore, in the case of a structure in which the discharge amount of the traction oil is adjusted according to the displacement speeds of the trunnions 8, 8, if the speed ratio changes suddenly, it can be said that it is a short time immediately after the start of the speed change operation. There is a possibility that the amount of traction oil supplied to each traction section will be insufficient.

On the other hand, in the case of this example, since the amount of traction oil supplied to each of the traction sections is increased by issuing a shift command, the shift operation of the toroidal continuously variable transmission is performed. Immediately after the start, traction oil can be sufficiently supplied to the traction units.
In addition, this example can also be implemented in combination with the first example or the second example of the embodiment described above. The configuration and operation of the other parts are the same as in the first example of the embodiment described above.

  The present invention is not limited to the half-toroidal type as long as it is a toroidal-type continuously variable transmission, and can also be implemented in a full-toroidal type. Furthermore, the present invention is not limited to the so-called double cavity type structure in which a pair of input side disks are provided as shown in FIGS. 1 and 2, but the so-called single cavity type in which one input disk and one output disk are provided. The toroidal type continuously variable transmission of the present invention can also be implemented.

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2a, 2b Input side disk 3 Ball spline 4 Tube member 5 Gear 6 Output side disk 7 Power roller 8 Trunnion 9 Support shaft 10 Tilt shaft 11 Drive shaft 12 Pressing device 13 Actuator 14 Gear ratio control valve 15 Stepping motor 16 Precess cam 17 Spool 18 Sleeve 19 Hydraulic source 20a, 20b Hydraulic chamber 21 Link arm 22 Rod

Claims (3)

At least one pair of discs that are concentric with each other and supported to freely rotate relative to each other in a state in which each side surface in the axial direction is a toroidal curved surface having an arc-shaped cross section,
With respect to the axial direction, a plurality of discs are provided at positions between the axial side surfaces of the respective discs, and swinging displacements centering on the tilting shaft located at a twisted position with respect to the central axis of each disc are freely provided. A support member;
Power rollers of the same number as each of the support members, each of which is rotatably supported by each of the support members and has a spherical convex surface brought into contact with one axial side surface of each disk.
In a toroidal type continuously variable transmission comprising: a lubricating device that supplies traction oil to a traction portion that is a rolling contact portion between one axial side surface of each disk and the peripheral surface of each power roller;
While the lubricating device is changing the gear ratio between the disks, the lubrication device discharges the traction oil that is discharged toward the traction portions according to the speed of change of the gear ratio between the disks. A toroidal-type continuously variable transmission characterized by having a function of adjusting the amount. By displacing each support member in the axial direction of each tilt axis by an actuator provided for each support member, and by swinging and displacing each support member about each tilt axis, It adjusts the gear ratio between disks.
The lubricating device responds to the displacement speed of the at least one support member among the support members in the axial direction of the tilt shafts while changing the speed ratio between the disks. The toroidal continuously variable transmission according to claim 1, wherein the amount of traction oil discharged toward each traction section is adjusted. At least one pair of discs that are concentric with each other and supported to freely rotate relative to each other in a state in which each side surface in the axial direction is a toroidal curved surface having an arc-shaped cross section,
With respect to the axial direction, a plurality of discs are provided at positions between the axial side surfaces of the respective discs, and swinging displacements centering on the tilting shaft located at a twisted position with respect to the central axis of each disc are freely provided. A support member;
Power rollers of the same number as each of the support members, each of which is rotatably supported by each of the support members and has a spherical convex surface brought into contact with one axial side surface of each disk.
In a toroidal type continuously variable transmission comprising: a lubricating device that supplies traction oil to a traction portion that is a rolling contact portion between one axial side surface of each disk and the peripheral surface of each power roller;
The lubrication device has a function of increasing the amount of traction oil discharged toward the traction sections immediately after the gear shift command is issued, on condition that the gear shift command is issued. Toroidal-type continuously variable transmission.

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