JP3994661B2 - Temperature control device for toroidal type continuously variable transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a toroidal continuously variable transmission used, for example, as a transmission of an automobile, and more particularly to temperature control thereof.
[0002]
[Prior art]
2. Description of the Related Art In recent years, a toroidal continuously variable transmission, which replaces a conventional automatic transmission, has attracted attention as a transmission for passenger cars. The variator, which is the main part of this toroidal-type continuously variable transmission, has an input disk and an output disk having concavely curved track surfaces arranged so that the track surfaces face each other, and a plurality of rollers are provided between the two disks. Are arranged. A terminal load due to hydraulic pressure is applied in the axial direction of each disk, whereby the rollers are pressed against the raceway surface of each disk via an oil film. The input disk is attached to an input shaft that is rotationally driven by the engine, and torque is transmitted from the input disk to the output disk via a roller by the rotation of the input disk. The speed change is performed steplessly by tilting the rotating shaft of the roller according to the required torque.
[0003]
[Problems to be solved by the invention]
The disks and the rollers are in contact with each other with an extremely high pressure through the oil film, so that the temperature of the hydraulic oil that forms the oil film also rises. When the temperature rises, the viscosity of the oil decreases, and as a result, the traction force may decrease, or the oil film may become thin and the disk and the roller may be in direct contact and be damaged.
On the other hand, when the temperature of the hydraulic oil is very low, for example, when the engine is started in winter in a cold region, the viscosity of the hydraulic oil becomes extremely high. For this reason, it is difficult to supply hydraulic oil evenly between each disk and roller. As a result, the traction force is reduced, or the oil film becomes thin and the disk and roller are in direct contact with each other and damaged. There is a fear.
[0004]
In view of the above-described conventional problems, an object of the present invention is to provide a temperature control device that maintains the temperature of hydraulic oil in an appropriate range under a wide range of temperature conditions in a toroidal-type continuously variable transmission. To do.
[0005]
[Means for Solving the Problems]
A temperature control device for a toroidal-type continuously variable transmission according to the present invention includes a case that houses a toroidal-type continuously variable transmission, a heat medium liquid passage that is provided along the case and distributes the heat medium liquid, and the toroidal A temperature sensor for detecting the temperature of the hydraulic oil in the continuously variable transmission, and supplying and discharging the heat medium liquid to and from the heat medium liquid passage portion, and based on the temperature of the hydraulic oil detected by the temperature sensor A heat medium liquid supply / discharge device that indirectly maintains the temperature of the hydraulic oil within a predetermined range by controlling the temperature and supply / discharge amount of the liquid, and the heat medium liquid supply / discharge device discharges the heat medium liquid An electric pump and an inverter that controls the supply / discharge amount by changing the number of revolutions of the electric pump are included (claim 1).
In the temperature control device for the toroidal-type continuously variable transmission configured as described above, the heat medium liquid supply / discharge device controls the temperature and supply / discharge amount of the heat medium liquid based on the temperature of the hydraulic oil detected by the temperature sensor. The temperature of the hydraulic oil is indirectly suppressed or lowered by promoting heat dissipation of the case, or the heated heat medium liquid is supplied and discharged to warm the case, thereby indirectly increasing the temperature of the hydraulic oil. Increases the viscosity.
[0006]
Moreover, in the said temperature control apparatus (Claim 1), a heat-medium liquid channel | path part may be formed between the outer peripheral surface of a case and the jacket which covers this (Claim 2).
In this case, a heat medium liquid passage having a large area can be easily secured between the case and the jacket.
[0007]
Further, in the temperature control device (claim 1), the heat medium liquid passage may be a pipe-like pipe wound around the outer periphery of the case (claim 3).
In this case, the heat medium liquid passes through the pipe line, thereby promoting heat dissipation or heating of the case. Also, the case need not be waterproof.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic diagram of a toroidal continuously variable transmission in a temperature control device for a toroidal continuously variable transmission according to a first embodiment of the present invention. The variator 1 constituting the main part of the toroidal type continuously variable transmission is provided with an input shaft 3 that is rotationally driven by an output shaft 2 of the engine. In the vicinity of both ends of the input shaft 3, input disks 4 are supported by spline coupling, and each input disk 4 rotates integrally with the input shaft 3. A concave curved track surface 4 a is formed on one side surface of each input disk 4. Further, each input disk 4 is restricted from moving away from each other by a locking ring 5 fixed to the input shaft 3.
[0009]
An output unit 8 including an output member 6 having a sprocket gear formed on the outer periphery and an output disk 7 supported by the output member 6 so as to be integrally rotatable with each other is provided at an axially central portion of the input shaft 3. It is provided so as to be rotatable relative to the input shaft 3. On one side surface of the output disk 7 facing the track surface 4a of the input disk 4, a concave curved track surface 7a is formed. The drive shaft 10 that transmits power to the drive wheels is provided in parallel with the input shaft 3 and includes a pair of sprocket wheels 10 a at positions corresponding to the output member 6. A chain 9 is attached to the output member 6 and the sprocket wheel 10 a so that power is taken out to the drive shaft 10.
[0010]
The output disk 7 is incorporated in a state in which fine movement in the axial direction is allowed with respect to the output member 6, and a backup plate 11 is disposed on the back surface thereof with a gap. The gap is sealed by a casing 12 and a seal (not shown). By supplying hydraulic pressure to the gap, the output disk 7 is urged toward the opposing input disk 4 and a predetermined terminal load is applied. Yes.
[0011]
Between the raceway surface 4a of the input disk 4 and the raceway surface 7a of the output disk 7 facing each other, a toroidal gap is formed, and the toroidal gap is in pressure contact with the raceway surfaces 4a and 7a, respectively. Three rotating disc-shaped rollers 13 are arranged at equal circumferences. Each roller 13 is supported by a carriage 14 so as to be rotatable and its rotation shaft is tiltable. The carriage 14 is configured to be given a driving force by hydraulic pressure.
[0012]
In the variator 1, torque is transmitted from the pair of input disks 4 to the corresponding output disks 7 via the six rollers 13. When torque is transmitted, a reaction force is generated in the roller 13, and this reaction force is supported by the driving force applied to the carriage 14. When an imbalance occurs between the reaction force and the torque required to drive the output disk 7, the roller 13 changes the shaft angle to eliminate the imbalance. For example, when a force is generated that causes the carriage 14 to be pushed back or pulled out against the driving force by hydraulic pressure due to fluctuations in travel load or acceleration / deceleration of the accelerator pedal, the shaft angle of the roller 13 changes (see FIG. 1). (See the two-dot chain line) The speed ratio is increased or decreased, and the torque output from the variator 1 changes. That is, the change in the ratio in the variator 1 is achieved only by adjusting the driving force applied to the carriage 14 and responding to the external resistance. The hydraulic oil that forms an oil film between the roller 13 and each of the disks 4 and 7 is supplied to the surface of the roller 13 via an internal passage (not shown) of the carriage 14.
[0013]
The variator 1 is accommodated in and supported by the case 20. The case 20 is formed by joining a plurality of members, and the outer peripheral surface thereof is finished without a gap, and the joint portion between the members is waterproofed by packing or the like. A jacket 21 is provided so as to cover the outer peripheral surface of the case 20 and with a gap between the case 20 and the case 21. The jacket 21 is waterproof so as not to leak water to the outside, and a heat medium liquid supply port 21a is provided at the lower portion and a discharge port 21b is provided at the upper portion. A space between the case 20 and the jacket 21 is a heat medium liquid passage portion P that fills and distributes the heat medium liquid. As the heat medium liquid, for example, the same coolant as that for engine cooling is used. By covering the case 20 with the jacket 21 as described above, the heat medium liquid passage portion P can secure a wide area.
[0014]
FIG. 2 is a diagram showing a configuration of a heat medium liquid supply / discharge device that supplies / discharges the heat medium liquid to / from the heat medium liquid passage portion P of the toroidal-type continuously variable transmission. The heat medium liquid supply / discharge device includes a radiator 22 that radiates heat medium liquid, a heater unit 23 that heats the heat medium liquid, an electromagnetic valve 24 provided on a discharge side path of the radiator 22, and an electric pump 25. And an inverter 26, a temperature sensor 27 that measures the temperature of the hydraulic oil, and a control device 28 that controls the solenoid valve 24, the heater unit 23, and the inverter 26 based on the temperature detected by the temperature sensor 27. As the motor of the electric pump 25, a brushless motor is employed from the viewpoint of noise prevention and maintenance-free. The inverter 26 converts the DC voltage supplied from the battery 26 a into an AC voltage and supplies it to the electric pump 25. By changing the frequency of the AC voltage by the inverter 26, the rotational speed of the electric pump 25, that is, the discharge amount can be made variable. The temperature sensor 27 is preferably provided in the vicinity of the raceway surfaces 4 a and 7 a, but is usually provided at the tip of the carriage 14.
[0015]
Next, the operation of the heat medium liquid supply / discharge device will be described.
When the temperature of the hydraulic oil detected by the temperature sensor 27 is higher than a predetermined temperature (for example, 100 ° C.), the control device 28 sets the electromagnetic valve 24 in a non-excited state, that is, the illustrated valve position. Further, the control device 28 turns off the heater unit 23.
[0016]
When the toroidal continuously variable transmission is operated and the temperature of the hydraulic oil rises to a predetermined value, the control device 28 outputs a drive signal to the inverter 26 and starts the operation of the electric pump 25. Accordingly, the heat medium liquid is sucked up from the radiator 22 and the heater unit 23 to the suction port 25a of the electric pump 25, and the heat medium liquid is sent from the discharge port 25b to the supply port 21a of the jacket 21 of the toroidal continuously variable transmission. . The fed heat medium liquid passes through the heat medium liquid passage portion P between the case 20 and the jacket 21 of the toroidal type continuously variable transmission, and deprives the case 20 of heat when passing. The heat medium liquid exiting from the outlet 21b of the jacket 21 returns to the electric pump 25 through the radiator 22 and the heater unit 23 in the off state. When passing through the radiator 22, the heat medium liquid dissipates heat and the temperature decreases.
[0017]
As described above, the amount of heat stored in the entire toroidal-type continuously variable transmission is reduced by depriving the heat of the case 20, and the temperature rise of the hydraulic oil is suppressed. That is, the hydraulic oil can be indirectly cooled by cooling the case 20. Further, the control device 28 controls the inverter 26 according to the temperature of the hydraulic oil to increase the discharge amount of the electric pump 25. As a result, the heat radiation amount per unit time is increased, and the cooling effect can be increased. Therefore, by controlling the discharge amount, that is, the supply / discharge amount of the heat medium liquid, the temperature rise of the hydraulic oil can be suppressed or the temperature can be lowered. Thereby, the traction force between each disk 4 and 7 and the roller 13 can be maintained in an appropriate range. Further, an oil film having an appropriate thickness is formed between each of the disks 4 and 7 and the roller 13, and damage to these members can be prevented.
[0018]
On the other hand, when the temperature of the hydraulic oil is lower than a predetermined temperature (for example, 100 ° C.), the viscosity is lowered, so it is necessary to heat it. Therefore, the control device 28 excites the electromagnetic valve 24 and blocks the path passing through the radiator 22. The control device 28 operates the electric pump 25 with the heater unit 23 turned on. Thereby, the heat medium liquid heated by the heater unit 23 is sucked up by the electric pump 25 and sent to the supply port 21a of the jacket 21 of the toroidal type continuously variable transmission. The heated heat medium liquid warms the case 20, radiates heat, and returns to the heater unit 23 again. The temperature of the case 20 rises as the heat medium liquid heated in this way circulates, and as a result, the temperature of the hydraulic oil rises indirectly. As a result, the viscosity of the hydraulic oil is lowered, and an appropriate amount of hydraulic oil can be supplied between each of the disks 4 and 7 and the roller 13. Accordingly, the traction force can be maintained within an appropriate range between each disk 4, 7 and the roller 13, and an oil film having an appropriate thickness is formed between each disk 4, 7 and the roller 13. The damage of these members can be prevented.
[0019]
As described above, when the temperature of the hydraulic oil is equal to or higher than a predetermined value, the temperature of the heat medium liquid and the supply / discharge amount are controlled to promote the heat dissipation of the case 20, and the temperature rise of the hydraulic oil is indirectly suppressed or reduced. The traction force can be maintained in an appropriate range. In addition, an oil film having an appropriate thickness can be formed between the disks 4 and 7 and the roller 13 to prevent damage to these members. Further, when the temperature of the hydraulic oil is lower than a predetermined value, the heated heat medium liquid is supplied and discharged to warm the case 20, thereby indirectly increasing the temperature of the hydraulic oil and lowering the viscosity, thereby reducing the traction force. Can be maintained within an appropriate range. In addition, an oil film having an appropriate thickness can be formed between the disks 4 and 7 and the roller 13 to prevent damage to these members.
In this way, the temperature of the hydraulic oil can be maintained within a predetermined temperature range (for example, 0 ° C. to 120 ° C.) under a wide range of temperature conditions, and an appropriate traction force can be ensured. An oil film having an appropriate thickness can be formed between the two members and damage to these members can be prevented. Furthermore, since the area of the heat medium liquid passage portion P is large as described above, the heat dissipation of the case 20 can be promoted or heated efficiently.
[0020]
FIG. 3 is a schematic view of a toroidal continuously variable transmission in a temperature control device for a toroidal continuously variable transmission according to a second embodiment of the present invention. The difference from the first embodiment is that, instead of providing the jacket 21, a pipe-shaped conduit 31 for passing the heat medium liquid is provided on the outer periphery of the case 20. The apparatus for supplying and discharging the heat medium liquid is the same as in the first embodiment. The heat medium liquid is supplied from the supply port 31a at one end of the conduit 31, and is discharged from the discharge port 31b at the other end.
In the case of this second embodiment, the effect of promoting heat dissipation or heating is somewhat reduced, but it is not necessary to make the case 20 waterproof, and only the pipe 31 is wound, so the configuration is simple.
[0021]
In each of the above embodiments, the heater unit 23 is provided separately from the toroidal type continuously variable transmission. Further, the hydraulic oil is not directly heated by the heater. Therefore, there is very little possibility that the hydraulic oil leaked due to a collision accident or the like is ignited by the heat of the heater. Moreover, since the electric pump 25 is driven only when necessary, there is no waste of energy. However, the pump need not be limited to an electric pump, and may be a pump driven by an engine output via a clutch.
[0022]
【The invention's effect】
The present invention configured as described above has the following effects.
According to the temperature control device of the toroidal type continuously variable transmission according to claim 1, the heat medium liquid supply / discharge device controls the temperature and supply / discharge amount of the heat medium liquid based on the temperature of the hydraulic fluid detected by the temperature sensor. The heat dissipation of the case is promoted to suppress or lower the temperature rise of the hydraulic oil indirectly, or the heated heat medium liquid is supplied and discharged to warm the case, thereby indirectly reducing the temperature of the hydraulic oil. Increase and decrease viscosity. Accordingly, the temperature of the hydraulic oil can be maintained within a predetermined temperature range under a wide range of temperature conditions, and an appropriate traction force can be ensured. In addition, an oil film having an appropriate thickness can be formed between the disk and the roller in the toroidal-type continuously variable transmission to prevent these members from being damaged.
[0023]
According to the temperature control device for the toroidal type continuously variable transmission according to the second aspect, it is possible to easily secure a heat medium liquid passage portion having a large area between the case and the jacket. Therefore, heat dissipation promotion and heating efficiency of the case are good.
[0024]
According to the temperature control device of the toroidal type continuously variable transmission according to claim 3, the heat medium liquid passes through the inside of the pipe line, thereby promoting heat dissipation or heating of the case. Therefore, the configuration of the heat medium liquid passage portion can be simplified without making the case waterproof.
[Brief description of the drawings]
FIG. 1 is a schematic view of a toroidal continuously variable transmission in a temperature control device for a toroidal continuously variable transmission according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a heat medium liquid supply / discharge device that supplies and discharges the heat medium liquid to and from the heat medium liquid passage portion of the toroidal-type continuously variable transmission.
FIG. 3 is a schematic view of a toroidal continuously variable transmission in a temperature control device for a toroidal continuously variable transmission according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Variator 20 Case 21 Jacket 22 Radiator 23 Heater unit 24 Electromagnetic valve 25 Electric pump 26 Inverter 27 Temperature sensor 28 Controller 31 Pipe line

Claims (3)

A case housing a toroidal-type continuously variable transmission;
A heat medium liquid passage section provided along the case for circulating the heat medium liquid;
A temperature sensor for detecting a temperature of hydraulic oil in the toroidal type continuously variable transmission;
While supplying / discharging the heat medium liquid to / from the heat medium liquid passage portion, the operating oil is indirectly controlled by controlling the temperature and supply / discharge amount of the heat medium liquid based on the temperature of the operating oil detected by the temperature sensor. and a heat medium fluid supply and discharge device for maintaining a predetermined range of temperature,
The heat medium liquid supply / discharge device includes an electric pump that discharges the heat medium liquid and an inverter that controls the supply / discharge amount by changing the rotation speed of the electric pump. Transmission temperature control device. The temperature control device for a toroidal continuously variable transmission according to claim 1, wherein the heat medium liquid passage portion is formed between an outer peripheral surface of the case and a jacket covering the case. The temperature control device for a toroidal-type continuously variable transmission according to claim 1, wherein the heat medium liquid passage portion is a pipe-like pipe wound around the outer periphery of the case.

Images