JP4026938B2 - Lubricator for continuously variable transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lubricating device for a continuously variable transmission that supplies lubricating oil to a forward / reverse switching device assembled in a belt type continuously variable transmission for a vehicle.
[0002]
[Prior art]
As a continuously variable transmission for a vehicle, a driven belt made of metal is mounted between a primary pulley provided on a drive shaft and a secondary pulley provided on a driven shaft, and the pulley diameter is changed by hydraulic pressure, thereby driving the driven shaft. There is something that changes the number of revolutions in a stepless manner. In such a continuously variable transmission, the rotation of the output shaft is switched between the forward direction and the reverse direction between the output shaft driven by the engine and the drive shaft, and transmitted to the drive shaft. Is provided with a forward / reverse switching device.
[0003]
This forward / reverse switching device has components such as a sun gear, a planetary pinion gear, and a bearing, and supplies lubricating oil to these components. For example, Japanese Patent Laid-Open No. 7-259944 discloses that an oil passage formed in communication with an oil pump is provided with an orifice, and through this orifice, lubricating oil is guided to the central shaft portion of the forward / reverse switching device, and the periphery of the shaft, etc. Discloses an oil passage structure in which a component such as a planetary pinion gear is forcedly lubricated.
[0004]
[Problems to be solved by the invention]
In this type of lubrication, when the vehicle is in a running state and the oil pump discharge amount is sufficient, the amount of oil supplied to the lubricating oil passage is sufficiently secured, and the forward / reverse switching device is installed. Lubricating oil is sufficiently supplied to each part by the centrifugal force applied to the lubricating oil by the rotation of the actuating member. However, in the idling operation, the discharge amount of the oil pump is considerably reduced. Even in this state, however, it is necessary to always maintain functional units such as a pulley operating cylinder and a torque converter that constitute the continuously variable transmission. For this reason, the flow rate of the lubricating oil, that is, the usage amount for lubrication with respect to the discharge amount from the oil pump cannot be secured sufficiently.
[0005]
It is desirable to reduce the size of the oil pump as much as possible in consideration of improvements in fuel consumption. However, since the oil pressure from the oil pump requires a high pressure of up to 50 kg / cm ² , idling can be done if the oil pump is downsized. Occasionally, there will be a shortage of lubricating oil, and there is a limit to downsizing the oil pump.
[0006]
An object of the present invention is to achieve downsizing of an oil pump while sufficiently securing the supply of lubricating oil to a forward / reverse switching device in a continuously variable transmission.
[0007]
[Means for Solving the Problems]
A lubricating device for a continuously variable transmission according to the present invention includes a primary pulley that is mounted on a drive shaft, a secondary pulley that is mounted on a driven shaft and a drive belt is spanned between the primary pulley, and is driven to rotate by an engine. A planetary pinion gear mounted between a carrier fixed to the output shaft and a sun gear fixed to the drive shaft, and switching the rotation of the output shaft to either the forward direction or the reverse direction. a lubricating device for a continuously variable transmission and a planetary-type forward-reverse switching device for transmitting to, in case the oil pump driven rotation is arranged by the engine, the leakage oil from the oil pump planetary A guide pipe that leads directly to the top of the pinion gear is attached .
[0008]
In the present invention, since oil leaked from the oil pump is guided to the forward / reverse switching device, the oil that generates the hydraulic pressure for changing the pulley widths of the primary pulley and the secondary pulley as in the idling state. Even when a sufficient amount of oil discharged from the pump cannot be ensured, the forward / reverse switching device can be lubricated using leak oil. Thereby, even when the oil pump is downsized, it is possible to reliably perform lubrication during idling.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0010]
FIG. 1 is a skeleton diagram showing a drive system of a continuously variable transmission for a vehicle using a belt. A crankshaft 1 driven by an engine (not shown) has a drive plate 4 attached to a pump side case 3 of a torque converter 2. The turbine runner 5 disposed so as to face the pump impeller 3 a provided in the pump side case 3 is directly connected to the turbine shaft, that is, the output shaft 6. A stator 7 is disposed between the pump impeller 3 a and the turbine runner 5 and supported by a one-way clutch 8. A lockup clutch 9 is directly connected to the output shaft 6 so as to be engageable and disengageable with a torque converter case on the drive plate 4 side, and engine power is transmitted to the output shaft 6 via the torque converter 2 or the lockup clutch 9. Communicated.
[0011]
The output shaft 6 is transmitted to the drive shaft 13 of the continuously variable transmission 12 via the forward / reverse switching device 11. A primary pulley 14 is provided on the drive shaft 13, and a primary-side movable sheave 14a is attached to the drive shaft 13 so as to be slidable in the axial direction by a ball spline or the like. The pulley interval is variable. A driven pulley 15 disposed in parallel to the drive shaft 13 is provided with a secondary pulley 16, and the movable sheave 16a on the secondary side is opposed to the driven shaft 15 in the axial direction similar to the movable sheave 14a. The secondary pulley 16 has a variable pulley interval.
[0012]
A drive belt 17 is stretched between the primary pulley 14 and the secondary pulley 16. By changing the groove width of both the pulleys 14, 16, the ratio of the winding diameter to the pulleys 14, 16 can be changed. As a result, the rotational speed of the driven shaft 15 is continuously variable.
[0013]
In order to change the groove width of the primary pulley 14, a cylinder 19 that forms an oil chamber 18 with the movable sheave 14 a is attached to the drive shaft 13, and in order to change the groove width of the secondary pulley 16, the movable sheave 16 a The driven shaft 15 is provided with a cylinder 22 that forms an oil chamber 21 therebetween.
[0014]
The driven shaft 15 is connected to the intermediate shaft 25 via gears 23, 24. A gear 26 attached to the intermediate shaft 25 meshes with a final gear 28 of the differential device 27, and an axle 29 a, connected to the differential device 27. Wheels 31a and 31b are attached to 29b. In the case of a front wheel drive vehicle, the wheels 31a and 31b are front wheels.
[0015]
Forward-reverse switching device 11 includes an output shaft of the circular having a forward clutch drum portion secured to 6 clutch cylinder 32, a clutch hub 33 fixed to through a spline portion to the drive shaft 13, A multi-plate forward clutch 34 is provided between the clutch drum portion provided in the clutch cylinder 32 and the clutch hub 33, and a hydraulic piston 35 for operating the forward clutch 34 serves as a clutch cylinder. 32. Therefore, when hydraulic pressure is supplied to the oil chamber 32a in the clutch cylinder 32 and the forward clutch 34 is connected, the rotation of the output shaft 6 is transmitted to the drive shaft 13 via the clutch hub 33 and the clutch cylinder 32 and driven. The shaft 13 rotates in the same forward direction as the output shaft 6.
[0016]
A ring gear 37 is rotatable on the outer side of the sun gear 36 fixed to the drive shaft 13 via a spline portion, and a planetary pinion gear that meshes with each other and forms a pair with a carrier 39 fixed to the clutch cylinder 32. 41 and 42 are rotatably mounted, one planetary pinion gear 41 meshes with the sun gear 36, and the other planetary pinion gear 42 meshes with the internal teeth of the ring gear 37, and these gears constitute a double pinion planetary gear. .
[0017]
In FIG. 1, the planetary pinion gears 41 and 42 are shown apart from each other for convenience of drawing. However, the planetary pinion gears 41 and 42 are engaged with each other in pairs, and a plurality of these planetary pinion gears 41 and 42 may be provided. good. A multi-plate type reverse brake 43 is provided between the ring gear 37 and the case 10, and a hydraulic piston 44 for operating the reverse brake 43 is incorporated in a brake cylinder 45 formed in the case 10. ing.
[0018]
Therefore, when the forward clutch 34 is released and the hydraulic pressure is supplied to the oil chamber 45a in the brake cylinder 45 to bring the reverse brake 43 into a braking state, the ring gear 37 is fixed to the case 10. Therefore, the rotation of the carrier 39 integrated with the output shaft 6 is transmitted to the sun gear 36 via the paired planetary pinion gears 41 and 42, and the drive shaft 13 is rotated in the reverse rotation direction opposite to that of the output shaft 6. Rotate. Thus, the reverse brake 43 is disposed on the primary pulley 14 side, and the forward clutch 34 is disposed on the torque converter 2 side, and the bearing that supports the shaft of the primary pulley 14 in order to shorten the overall length of the transmission. A brake cylinder 45 is disposed outside 46.
[0019]
In order to operate hydraulically operated devices such as the brake cylinder 45 and the clutch cylinder 32, an oil pump 47 as a hydraulic pressure source is disposed in the case 10, and the oil pump 47 is connected to the drive plate 4 and the torque by the crankshaft 1. It is driven via a sleeve of the pump side case 3 of the converter 2.
[0020]
FIG. 2 is a diagram showing a hydraulic circuit for controlling the operation of the drive system shown in FIG. 1. The oil pump 47 has a rotor driven by the engine and a pump housing on the case 10 side. Discharge ports 48a and 48b and two suction ports 49a and 49b are provided, and an inflow side oil passage 52 connected to an oil pan 51 is connected to the suction ports 49a and 49b.
[0021]
The discharge side oil passages 53a and 53b connected to the respective discharge ports 48a and 48b merge with the line pressure oil passage 54, and the line pressure oil passage 54 operates an oil chamber for operating the movable sheave 16a on the secondary pulley 16 side. 21 and to the line pressure ports of the transmission control valve 55 and the line pressure control valve 56. These control valves 55 and 56 are proportional electromagnetic relief valves, each having a solenoid that is operated by electric power from the control unit 57.
[0022]
The line pressure control valve 56 controls the pressure of the line pressure oil passage 54 in response to the current supplied from the control unit 57 to the solenoid, and the line pressure supplied to the oil chamber 21 of the secondary pulley 16, that is, the secondary pressure Ps. Control. A lubrication pressure oil passage 58 is connected to the lubrication port of the line pressure control valve 56, and a lubrication pressure Pc for lubrication lower than the line pressure is set by the line pressure control valve 56.
[0023]
The primary port of the speed change control valve 55 is connected to a primary oil passage 59 communicating with the oil chamber 18 for operating the movable sheave 14a on the primary pulley 14 side, and the speed change control valve 55 is supplied to the solenoid from the control unit 57. A primary pressure Pp corresponding to the current is supplied to the oil chamber 18. Since this primary pressure is set by adjusting the line pressure, it does not exceed the line pressure. However, since the cross-sectional area of the oil chamber 18 is set larger than the cross-sectional area of the oil chamber 21, the force for pinching the belt can be made larger than that on the secondary pulley side.
[0024]
When the engine output such as climbing or sudden acceleration is large, the line pressure is increased to prevent the belt 17 from slipping, and when the engine output is small, the line pressure is decreased to improve the loss of the oil pump 47 and the transmission efficiency. . These oil passages are provided with switching valves 61 that operate at a position where one discharge side oil passage 53b of the oil pump 47 is opened and a position where the discharge side oil passage 53b is bypassed to the inflow side oil passage 52, The switching valve 61 is operated by an electromagnetic valve 62 provided in an oil path 62 a that connects the lubricating pressure oil path 58 and the control port of the switching valve 61. Therefore, when preventing the loss of the oil pump 47, the discharge oil passage 53b can be stopped by energizing the solenoid valve 62, and the hydraulic pressure can be supplied to the line pressure oil passage 54 only from the discharge oil passage 53a. .
[0025]
In order to control the on / off operation of the lockup clutch 9 shown in FIG. 1, a lockup control valve 63 and a lockup operation electromagnetic valve 64 are provided in the hydraulic control circuit as shown in FIG. The electromagnetic valve 64 is turned on and off by a control signal from the control unit 57.
[0026]
When the vehicle speed exceeds a predetermined value, a lock-up on signal is sent from the control unit 57 to the solenoid valve 64, and the lubricating pressure oil passage 58 and the oil passage 65 are in communication with each other and the lubricating pressure is locked via the oil passage 65. This acts on the control port of the up control valve 63. At this time, the control pressure also acts on the first relief valve 66 connected between the oil passage 65 and the lubricating pressure oil passage 58, and the lubricating pressure Pc is set to a lower pressure Po. As a result, the spool of the lockup control valve 63 slides to the right in FIG. 2, and the lubricating pressure oil passage 58 flows into the oil passage 67 communicated with the apply chamber 9b, and this lubricating pressure flows into the apply chamber 9b. Supplied. As a result, the lockup clutch 9 is pushed to the left side to be in a lockup state, that is, a direct connection state, and the pressure in the release chamber 9 a is returned to the oil pan 51 via the oil passage 68.
[0027]
When a lock-up off signal is sent to the solenoid valve 64, the communication between the lubricating pressure oil path 58 and the oil path 65 is released and the oil path 65 is closed. As a result, the control pressure does not act on the control port of the lock-up control valve 63, the first relief valve 66 is less likely to drain, and the lubricating pressure is adjusted to a higher level. As a result, the spool of the lockup control valve 63 slides to the left side by the lubricating pressure acting on the port connected to the lubricating pressure oil passage 58 and the communication between the lubricating pressure oil passage 58 and the oil passage 67 is blocked. At this time, a second lubrication pressure PL lower than the aforementioned lubrication pressure Po is set by the second relief valve 69 connected to the drain port of the first relief valve 66, and the oil passage 70 connected to the drain port also enters the oil passage 70 connected to the drain port. Lubricating oil having a pressure of the lubricating pressure PL is discharged, and the hydraulic pressure is supplied to the release chamber 9 a through the oil passage 68.
[0028]
As a result, the lockup clutch 9 is turned off, that is, released, and the release hydraulic pressure is cooled by the oil cooler 72 via the oil passage 67 and the oil passage 71 and then returned to the oil pan 51. A relief valve 73 is connected to the oil passage 67 so that the lubricating oil is returned to the oil pan 51 when the pressure of the lubricating oil supplied into the apply chamber 9a exceeds a predetermined value.
[0029]
As described above, when the vehicle is advanced, hydraulic pressure is supplied to the oil chamber 32a in the clutch cylinder 32 of the forward clutch 34, and when the vehicle is moved backward, the oil chamber in the brake cylinder 45 of the reverse brake 43 is supplied. The hydraulic pressure is supplied to 45a, and the supply of hydraulic pressure to the oil chambers 32a and 45a is stopped otherwise. The oil chamber 32a is supplied with a lubricating pressure from the lubricating pressure oil passage 58, and the oil chamber 45a is supplied with a line pressure higher than the lubricating pressure.
[0030]
In this way, in order to operate the forward clutch 34 and the reverse brake 43, a clutch oil passage 75 for communicating the lubricating pressure oil passage 58 and the oil chamber 32a, and a brake for communicating the line pressure oil passage 54 and the oil chamber 45a. An oil passage 76 is provided, and these oil passages 75 and 76 are opened and closed by a manual valve 77. The manual valve 77 is operated by a select lever provided in the vehicle interior.
[0031]
The manual valve 77 is operated to the P range, R range, N range, and D range by a selector lever. When operated in the R range for moving the vehicle backward, the brake fluid passage 76 communicates with the line pressure fluid passage 54, and when operated in the D range for moving the vehicle forward, the clutch fluid passage 75 communicates with the lubricating pressure oil passage 58. When the manual valve 77 is operated to a position other than these, both the clutch oil passage 75 and the brake oil passage 76 are closed.
[0032]
The clutch oil passage 75 and the brake oil passage 76 are connected to accumulators 78 and 79, respectively, so as to absorb a switching shock at the time of switching between the forward state and the reverse state.
[0033]
A safety lock valve 81 is provided in the clutch oil passage 75 and the brake oil passage 76, and an electromagnetic valve 83 provided in an oil passage 82 connecting the control port of the safety lock valve 81 and the lubricating pressure oil passage 58 is operated. Accordingly, the communication between the clutch oil passage 75 and the lubricating pressure oil passage 58 is cut off, and the communication between the brake oil passage 76 and the line pressure oil passage 54 is cut off.
[0034]
FIG. 3 is an enlarged cross-sectional view showing a portion of the torque converter 2 and the forward / reverse switching device 11 shown in FIG. 1, and the output shaft 6 to which the rotation of the crankshaft 1 is transmitted via the torque converter 2 is shown. An oil passage 85 is formed connected to the oil passage 68 shown in FIG. A lubricating oil passage 86 communicating with the oil passage 85 via the outer peripheral surface of the output shaft 6 is formed in the output shaft 6, and a lubricating oil passage 87 communicating with the lubricating oil passage 86 is formed in the drive shaft 13. ing.
[0035]
The lubricating oil supplied to the lubricating oil passage 87 is supplied to the shaft portion of the sun gear 36 and the planetary pinion gears 41 and 42 provided on the drive shaft 13, the meshing portion of these gears 41 and 42 and the ring gear 37, and the like. It has become.
[0036]
The oil pump 47 is a high pressure pump, and the inner rotor of the pump is driven by an impeller sleeve 88 integrated with the pump side case 3 of the torque converter 2. Pump oil leaking from the bush 89 supporting the impeller sleeve 88 leaks considerably even when the engine is idling. In order to guide the leaked oil to the upper part of the forward / reverse switching device 11, a guide oil passage 91 is formed in the casing portion, and a guide pipe 92 is attached in communication with the guide oil passage 91. The lubricating oil flowing out from the guide pipe 92 is guided directly above the planetary pinion gears 41 and 42 and dropped onto the gears 41 and 42.
[0037]
With the lubricating device shown in FIG. 3, a sufficient amount of lubricating oil is supplied to the respective gears in the forward / reverse switching device 11 through the lubricating oil passages 85 to 87 when the vehicle is traveling. However, since the planetary pinion gears 41 and 42 do not perform planetary rotation with respect to the sun gear 36 and the ring gear 37 during forward traveling, the amount of lubricating oil is small.
[0038]
However, since the forward clutch 34 is released when the vehicle is stopped and in the N range state, the carrier 39 attached to the clutch cylinder 32 rotates, so that the planetary pinion gear 41 surrounds the sun gear 36 in the stopped state. , 42 is a planetary rotation. In particular, in the idling state, the amount of oil supplied from the lubricating oil passage 87 is reduced.
[0039]
Under this state, leak oil from the oil pump 47, that is, leaked oil, is dropped onto the planetary pinion gears 41 and 42 from the upper part of the forward / reverse switching device 11 through the guide oil passage 91 and the guide pipe 92. During idling, the carrier 39 and the planetary pinion gears 41 and 42 are idling at a low speed, and even if the lubricating oil is dripped from above, the lubricating oil can be supplied to a required lubricating location.
[0040]
It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.
[0041]
【The invention's effect】
In the present invention, since the forward / reverse switching device is lubricated by using the leak oil of the oil pump, the forward / reverse switching is performed even in an idling state where a sufficient amount of oil discharged from the oil pump cannot be secured. The device can be reliably lubricated. As a result, it is not necessary to increase the discharge rate from the oil pump outlet when idling, and the oil pump can be downsized, improved in function and durability, and further improved in fuel efficiency. Is possible.
[Brief description of the drawings]
FIG. 1 is a skeleton diagram showing a drive system of a continuously variable transmission having a lubricating device according to an embodiment of the present invention.
2 is a hydraulic circuit diagram showing a hydraulic system for controlling the operation of the continuously variable transmission shown in FIG. 1; FIG.
3 is an enlarged cross-sectional view showing a continuously variable transmission lubrication device provided in the torque converter and forward / reverse switching device in FIG. 1; FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Crankshaft 2 Torque converter 6 Output shaft 9 Lockup clutch 11 Forward / reverse switching device 12 Continuously variable transmission 13 Drive shaft 14 Primary pulley 15 Drive shaft 16 Secondary pulley 17 Drive belt 32 Clutch cylinder 34 Forward clutch 36 Sun gear 37 Ring gear 39 Carrier 43 Reverse brake 85 Oil passage 86, 87 Lubricating oil passage 91 Guide oil passage 92 Guide pipe

Claims (1)

A primary pulley mounted on a drive shaft, a secondary pulley mounted on a driven shaft and a drive belt is stretched between the primary pulley, a carrier fixed to an output shaft driven to rotate by an engine, and the drive A planetary forward / reverse switching device having a planetary pinion gear mounted between a sun gear fixed to a shaft and transmitting the rotation of the output shaft to the drive shaft by switching the rotation of the output shaft to either the forward direction or the reverse direction. A continuously variable transmission lubrication device comprising:
A lubricating device for a continuously variable transmission, wherein a guide pipe that guides leaked oil from the oil pump to a position directly above the planetary pinion gear is attached to a case where an oil pump that is rotationally driven by the engine is disposed .

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