JPH0587222A - Hydraulic controller of continuously variable transmission - Google Patents

Abstract

PURPOSE:To check the degree of hydraulic pulsation at the time of high temperature in a simple structure as well as to improve the responsiveness of hydraulic pressure at low temperature by installing a thermosensitive operating means, opening a bypass oil passage at low temperature while closing a bypass passage at high temperature, in this bypass passage bypassing an orifice of a separator plate. CONSTITUTION:A bypass passage 150 is installed after being interconnected to a line side oil passage 146 in order to bypass an orifice 148 at this line side oil passage 146, and it is opened or closed by a thermosenstive operating 152. In the case where a temperature of oil in a hydraulic control circuit 120 is low, the bypass oil passage 150 is opened, and hydraulic pressure controlled by a line solenoid valve 108 works from both sides, the orifice 148 and the bypass oil passage 150, thus even if oil viscosity is high, responsiveness in the hydraulic pressure can be improved. On the other hand, when the oil temperature is high, the bypass oil passage 150 is opened, and thereby the hydraulic pressure is passes through only from the line side oil passage 146 where the orifice 148 exists, thus any pulsation in the hydraulic pressure is checked by this orifice 148.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control system for a continuously variable transmission, and particularly when the oil temperature is high and the oil viscosity is low, hydraulic pulsation is suppressed, while the oil temperature is low and the oil viscosity is low. The present invention relates to a hydraulic control device for a continuously variable transmission that can improve hydraulic responsiveness when high.

[0002]

2. Description of the Related Art In a vehicle, a transmission is interposed between the internal combustion engine and the wheels because the characteristics of the internal combustion engine are not suitable as they are. This transmission changes the driving force and the rotation speed of the wheels in accordance with the traveling conditions of the vehicle that change over a wide range, and makes the internal combustion engine fully exhibit its performance.

As a transmission, there is a continuously variable transmission that changes the radius of rotation of a belt wound around a driving pulley and a driven pulley in accordance with a hydraulic pressure state to continuously change a gear ratio (belt ratio).

In FIG. 11, reference numeral 202 denotes an internal combustion engine, 20
4 is a continuously variable transmission. The continuously variable transmission 204 includes a drive side pulley 208 provided with a drive shaft 206 rotated by the internal combustion engine 202, and a driven shaft 212 rotated by a rotation of the drive pulley 208 via a belt 210.
And a driven pulley 214 provided with.

The drive shaft 206 and the driven shaft 212 are pivotally supported by a right case wall portion 220 of a right case 218 which constitutes a transmission case 216 and a left case wall portion 224 of a left case 222 which is a main case. ..

On the end side of the drive shaft 206, as shown in FIG.
As shown in FIG. 12, a valve body 226 provided with various hydraulic control valves is mounted on the left case wall portion 224 via a separate plate 228. That is, the body mounting surface 232 of the valve body 226 is mounted on the case mounting surface 230 that is one side wall surface of the left case wall portion 224. In this valve body 226,
As shown in FIG. 13, the first and second line pressure control valves 234 and 236, the ratio pressure control valve 238, the clutch pressure control valve 240, etc. as various hydraulic control valves, and the first solenoid valve as shown in FIG. A line solenoid valve 242 of the line pressure control valve 234, a ratio solenoid valve 244 of the ratio pressure control valve 238, a clutch solenoid valve 246 of the clutch pressure control valve 240, and the like are incorporated. As shown in FIG. 14, each case-side oil passage A forming each oil passage is formed in the case mounting surface 230 as a depression. On the body side mounting surface 232, as shown in FIG. 13, each body side oil passage B forming each oil passage is formed as a depression. Between the case mounting surface 230 and the body mounting surface 232, as shown in FIG. 15, there is a plate line pressure hole 248 which forms one of the plate side oil passages which connects the case side oil passage A and the body side oil passage B in a predetermined manner. The formed separate plate 228
Is installed. This plate line pressure hole 248 is
The first line pressure control valve 232 and the line solenoid valve 2
A line side oil passage 268, which will be described later, is formed so as to communicate with 40.

The operation of the continuously variable transmission 204 is controlled by a hydraulic control circuit 250 shown in FIG.

That is, as shown in FIG. 16, the hydraulic control circuit 2
As shown in FIG. 11, the oil pump 252 of 50 is provided at the end of the drive shaft 206, supplies oil to the line pressure passage 254 to generate a line pressure, and applies the line pressure to the driven pulley 214. Is.

In the line pressure passage 254, a first line pressure control valve 234, a second line pressure control valve 236, a ratio pressure control valve 238, a clutch pressure control valve 240, a manual shift valve 256, a relief valve 258, and a solenoid. The regulator valve 260 is in communication.

The ratio pressure control valve 238 communicates with the drive pulley 208 from the body ratio pressure passage 262 formed in the valve body 226 to apply a ratio pressure to the drive pulley 208.

A lube pressure passage 264 is connected between the oil pump 252 and the second line pressure control valve 236. A lube pressure regulator 266 is provided in the middle of the lube pressure passage 264.

The first line pressure control valve 234 and the line solenoid valve 242 are connected by a line side oil passage 268. In the middle of the line side oil passage 268, an orifice (a small-diameter hole) 270 that suppresses pulsation of hydraulic pressure when the oil temperature is high is provided. The orifice 270 is provided in the plate line pressure hole 248 of the separate plate 228.

A hydraulic control device for such a continuously variable transmission is disclosed, for example, in Japanese Patent Application No. 62-274750. The one disclosed in Japanese Patent Application No. 62-274750 is provided with a confirmation part capable of visually confirming the switching position of the switching valve at the time of assembly to the valve of the hydraulic control valve when completed.
The switching position of the switching valve can be confirmed from the outside so that the switching position of the switching valve can be confirmed easily and quickly.

[0014]

However, in the conventional hydraulic control device for a continuously variable transmission, as shown in FIG. 16, a line side pressure control solenoid side and another passage (case side) side are provided. An orifice 270 (a small-diameter hole) is provided in a separate plate 228 for partitioning the partition to suppress pulsation of hydraulic pressure when the oil temperature is high.

However, when the oil temperature is low and the viscosity of the oil is high, the presence of the orifice 270 makes it difficult for the control pressure to pass therethrough, resulting in a poor hydraulic response.

[0016]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention provides various hydraulic control valves on one side wall surface of a case wall portion of a transmission case which pivotally supports a drive shaft of a drive pulley. Provide a body mounting surface of the valve body that incorporates various solenoid valves that operate these various hydraulic control valves,
A case-side oil passage is recessed on one side wall surface of the case wall portion, and a body-side oil passage is recessed on the body side mounting surface of the valve body. A separate plate having a plate-side oil passage that connects the case-side oil passage and the body-side oil passage is provided between the body mounting surfaces of the plate, and the plate between the hydraulic control valve and the solenoid valve is provided. In a hydraulic control device for a continuously variable transmission having an orifice in a side oil passage, a bypass passage bypassing the orifice is provided to open the bypass oil passage at low temperature and close the bypass passage at high temperature. Means are provided.

[0017]

According to the structure of the present invention, when the oil temperature in the hydraulic control circuit is high, the temperature-sensing operation means closes the bypass oil passage, whereby the hydraulic pressure passes through the orifice. While suppressing the pulsation, when the oil temperature is low, the temperature-sensing operation means opens the bypass passage, which allows the hydraulic pressure to pass through both the orifice and the bypass passage, thus improving the hydraulic response. You can

[0018]

Embodiments of the present invention will now be described in detail and specifically with reference to the drawings. In FIG. 2, 2 is an internal combustion engine mounted on a vehicle, 4 is a continuously variable transmission, and 6 is a transmission case. The transmission case 6 includes a right case 8 on the internal combustion engine 2 side, a left case 10 that is a main case connected to the right case 8, and a side case 12 that is connected to the left case 10. Light case 8
The left side of the left case 10 is attached to the right case wall 1
4 are connected in a vertical direction in FIG.
Further, the left case wall portion 16 is continuously provided on the left case 10 on the joint side of the side case 12 and substantially parallel to the right case wall portion 14.

The continuously variable transmission 4 includes a drive pulley 18 and
The driven pulley 20, the driving pulley 18, and the driven pulley 2
The belt 22 is wound around 0 and is hydraulically controlled to change the radius of gyration of the belt 22 to continuously change the gear ratio.

The drive pulley 18 has a drive shaft 24 connected to the internal combustion engine 2, a drive-side fixed pulley portion 26 integrally provided on the drive shaft 24, and is movable in the drive shaft 24 in the axial direction. In addition, it has a drive side movable pulley portion piece 28 which is provided so as not to rotate. One end of the drive shaft 10 is pivotally supported by the right case wall portion 14, and the other end side thereof is pivotally supported by the left case wall portion 16. On the back side of the drive side movable pulley section piece 28, a drive side housing 32 that cooperates with the back side of the drive side movable pulley section piece 28 to form a drive side hydraulic chamber 30 is fixedly installed on the drive shaft 24. .. A drive shaft side oil passage 34 formed on the other end side of the drive shaft 24 communicates with the drive side hydraulic chamber 30.

An oil pump 36 is provided on the back side of the drive side fixed pulley portion piece 26. The oil pump 36 is driven by the rotation of the drive shaft 24,
The oil in the oil pan (not shown) is sucked and pressure-fed to the hydraulic control system and the lubrication system.

A damper 38 is provided in the light case 8 at one end of the drive shaft 24 on the internal combustion engine 2 side.

The driven pulley 20 is arranged in parallel with the drive shaft 24, and the driven shaft 40 is disposed corresponding to the drive side movable pulley portion 28 and is integrally provided with the driven shaft 40. A side fixed pulley section piece 42 and a driven side movable pulley section piece 44 that is arranged corresponding to the drive side fixed pulley section piece 26 and is axially movable and non-rotatable on the driven shaft 40. is doing. One end of the driven shaft 40 is pivotally supported by the right case wall portion 14, and the other end side thereof is pivotally supported by the left case wall portion 16. On the back side of the driven side movable pulley portion 44,
The driven-side housing 48 that forms a driven-side hydraulic chamber 46 in cooperation with the back surface of the driven-side movable pulley portion 44 includes a driven shaft 40.
It is fixed to. In the driven hydraulic chamber 46, the driven shaft 40
The driven shaft side oil passage 50 formed in the above is communicated.

Further, in the driven hydraulic chamber 46, the driven movable pulley portion 44 is pressed to the driven fixed pulley portion 42 side between the rear surface of the driven movable pulley portion 44 and the driven housing 48. The spring 52 is contracted.
The spring 52 sets the gear ratio to full low even when the rotation speed of the oil pump 36 is low and the line pressure (pump pressure) is low at the time of starting the internal combustion engine 2 and the belt 2
2 is given the minimum belt holding force to prevent slipping.

A hydraulic clutch 54 is provided on the rear side of the driven side fixed pulley portion piece 42. The hydraulic clutch 54 applies the driving force from the driven shaft 40 to the driven shaft 4
The clutch output shaft 56 is rotatably fitted on the clutch output shaft 56. A first drive gear 58 and a second drive gear 60 are fixedly mounted on the clutch output shaft 56.

A counter shaft 62 is pivotally supported by the right case wall portion 14 and the left case wall portion 16.

A reduction drive gear 66 of a reduction gear mechanism 64 is fixedly provided on one end of the counter shaft 62.
The reduction drive gear 66 includes a reduction driven gear 68.
Are meshed. The reduction driven gear 68 is fixed to the differential case 72 of the differential unit 70. Left and right wheel shafts 74, 74 are connected to the differential portion 70.

At the other end of the counter shaft 62, a reverse gear 78 forming a forward / reverse switching mechanism 76, a forward gear 80, the reverse gear 78 and the Ford gear 8 are provided.
A zero-to-zero synchromesh mechanism 82 is provided. The reverse gear 78 is connected to the first drive gear 58 via the reverse idler gear 86 of the reverse idler gear mechanism 84. Further, the forward gear 80 is directly meshed with the second drive gear 60.

As shown in FIG. 3, a valve body 92 is attached to a case mounting surface 88, which is one side wall surface of the left case wall portion 16 on the side case 12 side, via a separate plate 90. As shown in FIGS. 1 and 4, the valve body 92 has various hydraulic control valves including a first line pressure control valve 94, a second line pressure control valve 96, a ratio pressure control valve 98, a clutch pressure control valve 100, and cooling. Control valve 1
02 is installed at a predetermined position, a solenoid regulator valve 104 and a lube regulator valve 106 are installed at predetermined positions, and a line solenoid valve 108, a ratio solenoid valve 110, and a clutch solenoid valve 11 are further installed.
2 and 2 are installed in place.

On the body mounting surface 114 of the valve body 92, which is in contact with the separate plate 90, as shown in FIG. 4, various hydraulic passages of the hydraulic control circuit 120, which will be described later, and oils on the body side that form part of various oil passages are provided. The path A is formed as a depression.

As shown in FIG. 5, various hydraulic passages of the hydraulic control circuit 120 are provided on the case mounting surface 88, which is one side wall surface of the left case wall portion 16 of the left case 10 which is in contact with the separate plate 90 on the side case 12 side. Each case side oil passage B forming the other part of the various oil passages is formed to be recessed.

As shown in FIG. 6, the separate plate 90 is provided with a plurality of plate side oil passages for connecting the body side oil passage A of the valve body 92 and the case side oil passage B of the left case wall portion 16 in a predetermined manner. Has been formed.

That is, the separate plate 90 has
As shown in FIG. 6, a plate line pressure hole 116, which is one of the plate side oil passages that connects the line pressure control valve 94 and the line solenoid valve 108, and a plate bypass oil hole 118 are formed. Plate line pressure hole 116
Constitutes a line side oil passage 146 described later.
Further, the plate bypass oil hole 118 constitutes a bypass oil passage 150 described later.

Next, the hydraulic control circuit of the continuously variable transmission 4 will be described. That is, as shown in FIG. 1, the hydraulic control circuit 12
Reference numeral 0 has a plurality of hydraulic passages and oil passages for guiding the oil from the oil pump 36. The hydraulic passage and the oil passage are constituted by the body side oil passage A, the case side oil passage B, and the plate side oil hole.

More specifically, one end of the line pressure passage 122 is connected to the oil pump 36. The oil pump 36 pumps the oil sucked from the oil strainer 124 in the oil pan to the line pressure passage 122 to generate a line pressure. This line pressure passage 12
The other end side of 2 is the driven side hydraulic chamber 46 of the driven pulley 20.
Is in communication with.

In the line pressure passage 122, the first oil passage 1
The first line pressure control valve 94 is connected via 26,
The second line pressure control valve 96 is connected via the oil passage 128, the ratio pressure control valve 98 is connected via the third oil passage 130, the clutch control valve 100 is connected via the fourth oil passage 132, The manual shift valve 136 is connected via the fifth oil passage 134, the solenoid regulator valve 104 is connected via the sixth oil passage 138, and the seventh oil passage 14 is connected.
The relief valve 142 is connected via 0.

The first line pressure control valve 94 and the second line pressure control valve 96 are connected by an eighth oil passage 144. A line side oil passage 146 as a ninth oil passage provided with a line solenoid valve 108 is connected to the first line pressure control valve 94.

In the middle of the line side oil passage 146, an orifice 148 for suppressing hydraulic pressure pulsation when the oil temperature is high.
Is provided. The orifice 148 is provided in the line pressure hole 116 of the separate plate 90.

A bypass passage 150 is provided in communication with the line side oil passage 146 so as to bypass the orifice 148. The bypass passage 150 has a temperature-sensing operating means 15
It is opened and closed by 2. As shown in FIG. 7, the temperature-sensitive operating means 152 is, for example, a thermo switch 158 including a plunger 154 and a wax body 156, or
As shown in FIG. 8, it comprises a bimetal valve 160.

The temperature-sensing operating means 152 opens the bypass passage 150 when the oil temperature is low, and closes the bypass passage 150 when the oil temperature is high, that is, closes the plate bypass oil hole 118.

When the temperature-sensitive operating means 152 is the thermoswitch 158, the wax body 156 is held and fixed on the left case wall portion 16 as shown in FIG.

The ratio pressure control valve 90 is connected to a tenth oil passage 162 provided with a ratio solenoid valve 110. Line side oil passage 146 and tenth oil passage 16
2 is connected at the connecting portion 164.

The ratio pressure control valve 98 is connected to one end of the body ratio pressure oil passage 114 formed in the valve body 92. The other end side of the body ratio pressure oil passage 114 communicates with the drive side hydraulic chamber 30 of the drive pulley 18. An eleventh oil passage 166 communicating with the cooling control valve 102 is connected in the middle of the body ratio pressure passage 114.

The cooling control valve 102 has a twelfth
An oil cooler 170 is connected via an oil passage 168, the clutch pressure control valve 100 is connected via a thirteenth passage 172 on which clutch pressure acts, and the hydraulic clutch 54 is connected via a cooling oil passage 174. There is. A fourteenth oil passage 176 communicating with the manual shift valve 136 is connected in the middle of the thirteenth passage 172.

The clutch pressure control valve 100 has a fifteenth
The clutch solenoid valve 112 is connected via the oil passage 178.

The hydraulic clutch 54 includes a sixteenth oil passage 18
0 to the shift servo valve 182 of the shift mechanism.

The shift servo valve 182 includes a servo cylinder 184, a servo piston 188 that moves in the servo cylinder 184 to form a hydraulic chamber 186, a shift servo rod 190 fixed to the servo piston 188, and A shift fork 19 fixed to the shift servo rod 190 to operate the forward / reverse switching mechanism 76.
2 and.

A lube pressure passage 194 is connected between the oil pump 36 and the second line pressure control valve 96. The lube pressure regulator valve 106 is provided in the middle of the lube pressure passage 194.

Next, the operation of this embodiment will be described.

In the continuously variable transmission 4, the line pressure from the oil pump 36 is supplied to the line pressure passage 122 of the hydraulic control circuit 120.
Is supplied to the solenoid valve, each solenoid valve is operated by a control means (not shown), and each hydraulic control valve such as the first line pressure control valve 94 is operated in the vehicle state to change the gear ratio and the like. ..

In this embodiment, when the oil temperature in the hydraulic control circuit 120 is low, the bypass oil passage 150 is opened, that is, the plate line pressure hole 116, as shown in FIGS. Is closed, and the hydraulic pressure controlled by the line solenoid valve 108 acts from both the line side oil passage 146 where the orifice 148 exists and the bypass oil passage 150, whereby even if the oil viscosity is high,
The hydraulic response can be improved.

On the other hand, when the oil temperature is high, as shown in FIG.
As shown in FIG. 10, since the temperature-sensing operating means 152 closes the bypass oil passage 150, the oil pressure from the line solenoid valve 108 causes the hydraulic pressure from the line solenoid valve 108 to exist in the line-side oil passage 146 where the orifice 148 exists.
Only through the orifice 14 and thus the hydraulic pulsation
8 effectively suppressed.

As a result, when the oil viscosity is high at low temperature, the area of the control oil pressure passage portion is increased to improve the hydraulic response, and at the time of high temperature the area of the control oil pressure passage portion is increased. Orifice 14 reduces hydraulic pulsation that tends to occur when oil viscosity is low.
8 can effectively prevent it.

Further, since the bypass passage 150 is not linear and is opened / closed by the temperature sensitive operation means 152, that is, either opened or closed, the structure is simple, and maintenance and inspection are possible. It's easy and cheap.

[0055]

As is apparent from the above detailed description, according to the present invention, the bypass passage bypassing the orifice formed in the separator plate is provided, and the bypass oil passage is opened at a low temperature and the bypass oil passage is opened at a high temperature. By providing the temperature-sensing actuating means that sometimes closes the bypass passage, hydraulic pressure pulsation can be suppressed at high temperatures, and hydraulic responsiveness can be improved at low temperatures.

Further, according to the structure of the present invention, the structure is simple, maintenance and inspection can be facilitated, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a hydraulic control circuit diagram of a continuously variable transmission.

FIG. 2 is a sectional view of a continuously variable transmission.

FIG. 3 is an enlarged view of a main part of the continuously variable transmission in FIG.

FIG. 4 is a front view of a valve body.

FIG. 5 is a front view of a case mounting surface of the left case.

FIG. 6 is a front view of a separate plate.

FIG. 7 is a cross-sectional view of a temperature-sensing operating means including a thermoswitch at low temperature.

FIG. 8 is a schematic view of a temperature-sensing operating means including a bimetal valve at a low temperature.

FIG. 9 is a cross-sectional view of a temperature-sensing operating means including a thermoswitch at high temperature.

FIG. 10 is a schematic view of a temperature-sensing operating means including a bimetal valve at a high temperature.

FIG. 11 is a sectional view of a conventional continuously variable transmission.

12 is an enlarged view of a main part of the continuously variable transmission shown in FIG.

FIG. 13 is a front view of a conventional valve body.

FIG. 14 is a side view of a case mounting surface of a conventional left case wall portion.

FIG. 15 is a front view of a conventional separate plate.

FIG. 16 is a hydraulic control circuit diagram of a conventional continuously variable transmission.

[Explanation of symbols]

 2 Internal Combustion Engine 4 Continuously Variable Transmission 10 Left Case 16 Left Case Wall 18 Drive Pulley 20 Driven Pulley 22 Belt 24 Drive Shaft 40 Driven Shaft 90 Separate Plate 92 Valve Body 98 Ratio Pressure Control Valve 116 Plate Line Pressure Hole 118 Plate Bypass Oil Hole 146 Line side oil passage 148 Orifice 150 Bypass oil passage 152 Temperature sensitive operating means

Claims (1)

[Claims] 1. A body mounting of a valve body in which various hydraulic control valves and various solenoid valves for operating the various hydraulic control valves are mounted on one side wall surface of a case wall portion of a transmission case which pivotally supports a drive shaft of a drive pulley. A side surface of the case wall is provided with a case-side oil passage recessed, and a body-side mounting surface of the valve body is provided with a body-side oil passage provided with a recess. And a body mounting surface of the valve body, there is interposed a separate plate having a plate-side oil passage that connects the case-side oil passage and the body-side oil passage in a predetermined manner, the hydraulic control valve and the solenoid valve. In a hydraulic control device for a continuously variable transmission having an orifice in the plate-side oil passage between them, a bypass passage bypassing the orifice is provided, and the bypass oil passage is opened at a low temperature and high temperature is maintained. A hydraulic control device for a continuously variable transmission, characterized in that a temperature-sensing operating means for closing the bypass passage is provided at times.