JPS5977156A - Line pressure control device for v-belt type stepless speed change gear - Google Patents

Abstract

PURPOSE:To keep off a slip in a V-belt as well as to improve the speed change responsiveness ever so better, by connecting a port, which is supplied with line pressure when a spool in a speed change control valve is displaced beyond the specified value in a direction of enlarging a speed change ratio, to a pressure boosting port of a line pressure relief valve. CONSTITUTION:When stepping on an accelerator pedal so quickly, a speed change controller 300 gives a step motor 110 an opening signal quickly rotates a pinion gear 110a toward the large side of a speed change ratio. A spool 174 in a speed change control valve 106 is temporarily shifted to the left side via a speed change control mechanism 112, and ports 172a and 172b are interconnected with each other in position between lands 174a and 174b whereby line pressure is fed to an oil passage 160. This line pressure acts on a port 146a of the speed change control valve 106 and gives right-handed force to a spool 148 so that the line pressure rises. With a temporary rise in the line pressure, oil is quickly fed to a driven pulley cylinder chamber 56 whereby rapid speed change takes place, thus speed change responsiveness is improved and any possible slips in a V-belt are checked.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to line pressure control manufacturing cost of a V-belt type continuously variable transmission.

As a conventional speed change control valve for a V-belt type continuously variable transmission, for example, British Patent No. 989. ．． There is one as shown in Figure 1 described in No. 227. This speed change control valve 200 has a valve hole 201 having five ports 201a, 201b, 201c, 201d, and 201e, and four lands 202a, 202b, 202c, and 2 corresponding to the valve hole 201.
02d. Line pressure is supplied to the central port 201c via an oil passage 203, and the ports on its left and right) 201b and 201d
are in communication with the drive pulley cylinder chamber of the driving/driving pulley and the driven pulley cylinder chamber of the driven pulley via oil passages 204 and 205, respectively. Ports 201a and 2 at both ends
01e are both drained. The left end of the spool 202 is connected to a lever of a speed change operation mechanism (not shown). The axial lengths of the lands 202b and 202c are slightly smaller than the widths of the ports 201b and 201d, and the distance between the lands 202b and 202c is smaller than the width of the ports 201b and 201d.
The distance is approximately equal to the distance between 01b and 201d. Therefore, there is a hole in the oil chamber between lands 202b and 202c.
The line pressure supplied from 01c flows into the oil passage 204 through the gap between the land 202b and the port 201b, but part of it is drained from the other gap between the land 202b and the port 201b, so the line pressure flows into the oil passage 204. The pressure 204 is determined by the area ratio of the internal gap. Similarly, the pressure in the oil passage 205 is determined by the ratio of the areas of the gaps on both sides of the land 202C and the port 201d. Therefore, when the spool 202 is in the center position, the relationship between the land 202b and the port 201b and the relationship between the land 202C and the port 201d are the same, so the oil passage 204 and the oil passage 205 have the same pressure. As the spool 202 moves to the left, the clearance on the line pressure side of the boat 201b becomes larger and the clearance on the retrain side becomes smaller, so the pressure in the oil passage 204 gradually increases, and conversely, the clearance on the line pressure side of the boat 201d increases. As the drain side gap becomes larger, the pressure in the oil passage 205 gradually decreases. Therefore, the pressure in the driving pulley cylinder chamber of the driving pulley increases and the width of the V-shaped pulley groove becomes smaller, while the pressure in the driven pulley cylinder chamber of the driven pulley decreases and the width of the V-shaped pulley groove increases. , the V-belt contact radius of the driving pulley becomes larger and the V-belt contact radius of the driven pulley becomes smaller, so the reduction ratio becomes smaller. On the contrary, spool 202
If you move it to the right, the effect is completely opposite to the above, and
The reduction ratio becomes larger. However, such conventional speed change control valves have a problem in that when there is sudden acceleration, the oil pressure in the pulley and cylinder chamber decreases, causing the V-belt to slip. When rapid acceleration is to be performed, the spool 202 is pushed approximately 5 mm to the right in FIG. 1 by the speed change operation mechanism, resulting in the state shown in FIG. 2. As a result, the gap between the port 201b and the left side of the land 202b suddenly increases, and the oil pressure in the oil passage 204 (that is, the oil pressure in the drive pulley cylinder chamber) is reduced by the port 201a.
It is momentarily drained through the V-belt, causing slippage between the drive pulley and the V-belt. Furthermore, when the V-belt slips, its tension decreases, so the axial force exerted by the V-belt on the driven pulley also decreases, causing the movable conical plate of the driven pulley to move. Since this movement is faster than movement due to line pressure being supplied, the oil pressure in the driven pulley cylinder chamber also temporarily decreases. FIG. 3 shows changes in oil pressure in this case. Due to the drop in oil pressure during gear shifting, the oil pressure in both pulley cylinder chambers becomes smaller than the minimum oil pressure required for torque transmission, resulting in slippage. For this reason, when the vehicle accelerates rapidly, the engine may run dry.

In order to avoid the above-mentioned problems, it may be possible to set the line pressure high in advance in anticipation of a drop in oil pressure, but this would result in excessive force acting on the V-block during normal operation, causing This causes deformation, wear, etc., and the tension acting on the V-belt also increases, reducing the life of the V-belt. Furthermore, increasing the oil pressure increases oil pump loss and reduces the efficiency of the entire V-belt continuously variable transmission.

Another way to avoid the above-mentioned problems is to connect the drain oil passage of the speed change control valve (port h in Figure 1).
201a and 201e) to prevent the oil pressure from dropping suddenly. but,
With this method, the oil pressure changes slowly, reducing shift response and driving feeling.

In order to solve the above problems, the applicant has filed a patent application filed in 1983-
No. 71512 "Line Pressure Control Method for RV and 1ZL Continuously Variable Transmissions" (filed on April 30, 1980),
A switching valve boat that is provided with a switching valve that interlocks with the spool of the speed change control valve, and communicates with the pressure increasing boat of the line pressure regulating valve when the spool of the speed change control valve moves significantly in the direction of the speed ratio upward or downward. A line pressure control device designed to drain the water is shown. However, in this line pressure control device, when the spool of the switching valve moves, the switching valve port that communicates with the pressure increase port of the line pressure regulating valve is connected to one of the drain boats placed on both sides of the boat. Because they were designed to communicate with each other, the switching valve required three boats, and the integrated speed change control valve and switching valve had a very long overall length. For this reason, there are problems in that the hydraulic control device becomes large in size, and machining of the valve hole and spool is troublesome and it is difficult to achieve accuracy.

The present invention was made by focusing on the above-mentioned problems in the line pressure control device of the conventional V-belt type continuously variable transmission. It is an object of the present invention to solve the above-mentioned problems by connecting a port to which line pressure is supplied when displaced to a pressure increasing port of a line pressure regulating valve.

In other words, the line pressure should be increased only in the case of a sudden shift to the large gear ratio side, and there is no problem in driving feeling even if the gear ratio is not shifted rapidly to the small gear ratio side.)
Also, instead of draining the port that communicates with the pressure increase port of the line pressure regulating valve through a separate drain port,
The purpose is to reduce the number of required ports by supplying line pressure to these ports.

Hereinafter, the present invention will be described in the fourth and fifth figures of the attached drawings showing the embodiments thereof.
This will be explained based on the diagram.

FIG. 4 shows a power transmission mechanism of a continuously variable transmission to which the present invention is applied. An input shaft 2 connected to a crankshaft of an engine can be connected to a drive shaft 8 provided with a drive pulley 6 via a forward clutch 4 . The input shaft 2 is equipped with an external gear type oil pump 1, which is a hydraulic pressure source for hydraulically controlled loading, which will be described later.
o is provided. The oil pump 10 has a drive gear 12
and a driven gear 14. A rotary groove 16 is attached to the input shaft 2 so as to be integrally rotatable.The rotary groove 16 forms an oil pool 18 by bending the outer periphery of a substantially disc-shaped plate inward. It is designed to hold oil which rotates together with the rotating gutter 16. Note that it is preferable that the oil pool 18 be formed with irregularities that act as vanes to improve the ability of the oil to follow changes in the rotation of the rotary gutter 16. Further, the rotating gutter 16 is provided with a conduit (not shown) that always supplies a predetermined amount of oil into the yuzu reservoir 18. A pitot tube 20 having an opening facing the flow of oil that rotates together with the rotating groove 16 faces into the oil pool 18 of the rotating groove 16, and the dynamic pressure of the oil in the oil basin 18 is controlled by the Pitot tube 20. −? It is detectable by the agency 20. A subshaft 22 is rotatably provided parallel to the input shaft 2, and a reverse clutch 24 is provided at one end of the subshaft 22. The input shaft 2 and the countershaft 22 each have gears 26 and 28 that mesh with each other. The gear 26 can always rotate integrally with the input shaft 2, and the gear 28 can rotate integrally with the subshaft 22 via the reverse clutch 24. A gear 34 is integrally provided on the other end side of the subshaft 22, and the gear 34 meshes with the gear 32 that is rotatably supported.

The gear 32 meshes with a gear 30 that can rotate integrally with the drive shaft 8. Forward clutch 4 and reverse clutch 24
are configured to be fastened when hydraulic pressure is introduced into the piston chambers 36 and 38 from a hydraulic control device, which will be described later. When the forward clutch 4 is engaged, the engine rotation transmitted from the input shaft 2 is transmitted to the drive shaft 8 with normal rotation, while when the reverse clutch 24 is engaged, the engine rotation is transmitted through the gears 26, 28, 34. .32 and 30, the rotation is reversed and transmitted to the drive shaft 8.

The drive pulley 6 includes a fixed conical plate 40 integrally formed with the drive shaft 8, and a V-shaped pulley groove formed by opposing the fixed conical plate 40, and a drive pulley cylinder chamber 42.
The movable conical slope 44 is movable in the axial direction of the drive shaft 8 by hydraulic pressure acting on the movable conical slope 44. Note that the maximum width of the V-shaped pulley groove is regulated by a stopper (not shown) that acts when the movable conical plate 44 moves a predetermined amount to the left in the figure. The fixed conical plate 40 of the drive pulley 6 also has a rotational groove 46 that is almost the same as the rotational groove 16 described above.
is the provision. The dynamic pressure of the oil in the oil reservoir 47 of the rotary gutter 46 can be detected by the pitot V48, and a predetermined amount of oil is always supplied into the oil reservoir 47 by an oil pipe (not shown). The driving pulley 6 is transmission-connected to a driven pulley 51 by a V-belt 50, and the driven pulley 51 is provided on a rotatable driven shaft 52. The driven pulley 51 includes a fixed conical plate 54 formed integrally with the driven shaft 52, and a hydraulic pressure and a spring 57 arranged opposite to the fixed conical plate 54 to form a V-shaped pulley groove and acting on the driven pulley cylinder chamber 56. A movable conical plate 58 that is movable in the axial direction of the driven shaft 52 by
It consists of. As in the case of the drive pulley 6, the axial movement of the movable conical plate 58 is limited by a stopper (not shown) to prevent it from exceeding the maximum V-shaped pulley groove width. In addition, the driven pulley cylinder chamber 5
The pressure receiving area of No. 6 is approximately 1/2 of the pressure receiving area of the drive pulley cylinder chamber 42. A gear 60 provided to rotate integrally with the driven shaft 52 meshes with a ring gear 62. That is, the rotational force of the driven shaft 52 is transmitted to the ring gear 62 via the gear 60. A pair of pinion gears 6 are attached to the differential case 64 to which the ring gear 62 is attached.
6 and 68 and a pair of side gears 72 and 74 that mesh with the pinion gears 66 and 68 to form a differential device 70 are provided. Output shafts 76 and 78 are connected to the side gears 72 and 74, respectively.

The rotational force input from the engine crankshaft to the power transmission mechanism of the continuously variable transmission as described above is transmitted from the input shaft 2 to the drive shaft 8 via the forward clutch 4 (or from the input shaft 2
From gear 26, gear 28, reverse clutch 24, subshaft 2
2. Drive shaft 8 via gear 34, gear 32, and gear 30
), then is transmitted to the drive pulley 6, V-belt 50, driven pulley 51, and driven shaft 52, further inputted to the ring gear 62 via the gear 60, and then outputted by the action of the differential device 70. Rotational force is transmitted to shafts 76 and 78. During the above power transmission, if the forward clutch 4 is engaged and the reverse clutch 24 is released, the drive shaft 8 rotates in the same direction as the input shaft 2, and the output shafts 76 and 78 rotate in the forward direction. be done. Conversely, when the forward clutch 4 is released and the reverse clutch 24 is engaged, the drive shaft 8 rotates in the opposite direction to the input shaft 2, and the output shafts 76 and 78 rotate in the reverse direction.

During this power transmission, the movable conical plate 44 of the drive pulley 6
By moving the movable conical plate 58 of the driven pulley 51 in the axial direction and changing the radius of the contact position with the V-belt 50, the rotation ratio between the drive pulley 6 and the driven pulley 51 can be changed. For example, if the width of the V-shaped pulley groove of the driving pulley 6 is expanded and the width of the V-shaped pulley groove of the driven pulley 51 is reduced, the radius of the V-belt contact position on the driving pulley 6 side becomes smaller, and the driven pulley 51 The radius of the V-belt contact position on the side becomes larger, and a larger gear ratio can be obtained as a result. If the movable conical plates 44 and 58 are moved in the opposite direction, the gear ratio will become smaller, in the exact opposite way to the above.

Next, a hydraulic control device for this continuously variable transmission will be explained. The hydraulic control device includes an oil pump 1 as shown in FIG.
0, line pressure regulating valve 102, manual valve 104, speed change control valve 106, clutch complete engagement control valve 108, speed change motor 110, speed change operation mechanism 112, throttle valve 114,
Starting valve 116, start adjustment valve 118, maximum gear ratio holding valve 120, reverse inhibitor valve 122,
It consists of a lubricating valve 124 and the like.

The oil pump 10 is driven by the input shaft 2 as described above, and sucks oil in the tank 130 through the oil tank 131 and discharges it into the oil path 132. The oil discharged from the oil passage 132 is delivered to ports 146d and 146 of the line pressure regulating valve 102.
e, and the line pressure is regulated to a predetermined pressure as described later. The oil passage 132 also communicates with the port 192C of the throttle valve 114 and the boat 172b of the speed change control valve 106. The oil passage 132 also communicates with the driven pulley cylinder chamber 56. That is, line pressure is always supplied to the driven pulley cylinder chamber 56.

The manual valve 104 has four boats 134a and 134b.
, 134c and 134d, and two lands 136a and 136b corresponding to this valve hole 134.
The spool 136 has a spool 136. The spool 136, operated by a select lever (not shown) on the driver's seat, has five stop positions: P, R, N, D, and L ranges. The port 134a is a drain boat, and the port 134b communicates with the port 240C of the reverse inhibitor valve 122 through an oil passage 138. Further, the port 134c communicates with the port 204a of the starting valve 116 through an oil passage 140, and the port 134c
4d communicates with the piston chamber 36 of the forward clutch 4 through an oil passage 142. When the spool 136 is in the P position, the port 134C to which the oil passage 140 is pressurized is closed by the land 136b, and the piston chamber 36 of the forward clutch 4 is It is drained through the oil passage 142 and the port 134d, and the piston chamber 38 of the reverse clutch 24 is drained through the oil passage 144 and the reverse inhibitor valve 122.
port) 240b and 240C1 are drained through oil passage 138 and port 134b. Spool 136 is R
When in the position, the port 134b and the port 134C communicate between the lands 136a and 136b, and the oil passage 14 is connected to the piston chamber 38 of the reverse clutch 24 (when the reverse inhibitor valve 122 is in the upper half state in the figure).
A starting pressure of 0 is supplied, while the piston chamber 36 of the forward clutch 4 is drained via port 134cl. When the spool 136 is in the N position, the port 134C
is sandwiched between lands 136a and 136b and cannot communicate with other ports, while port 134b
and 1.34d are both drained, so the piston chamber 38 of the reverse clutch 24 and the piston chamber 36 of the forward clutch 4 are both drained, as in the case of the P position. When spool 136 is in the D or L position, ports 134c and 134d are connected to lands 136a and l.
:36. b, and line pressure is supplied to the cylinder chamber 36 of the forward clutch 4, while the piston chamber 38 of the reverse clutch 24 is drained through the port 134b. As a result, the spool 136 eventually becomes P
Alternatively, when the forward clutch 4 and the reverse clutch 24 are in the N position, both the forward clutch 4 and the reverse clutch 24 are released, power transmission is cut off, and the rotational force of the input shaft 2 is not transmitted to the drive shaft 8, and when the spool 136 is in the R position, the reverse clutch 4 is released. The clutch 24 is engaged (
When the reverse inhibitor turbo ↑ 122 is in the upper half state in the figure), the output shafts 76 and 78 are driven in the backward direction as described above, and when the spool 136 is in the D or L position, the forward clutch 4 is engaged. output shafts 76 and 78
will be driven in the forward direction. In addition, D position and L
As mentioned above, there is no difference between the position and the hydraulic circuit, but the reposition is electrically detected and the operation of the speed change motor 110 (described later) is controlled so that the speed is changed according to a different speed change pattern. be done.

The line pressure regulating valve 102 has six ports 146a, 14
A valve hole 146 having 6b, 146c, 146d, 146e and 146f, and five lands 148a, 148b, 148C1148d and 14 corresponding to this valve hole 146.
8e, a sleeve 150 that is freely movable in the axial direction, and two springs 1527J and 1527J provided in parallel between the spool 148 and the sleeve 150.
It consists of 54. The sleeve 150 is attached to the bottle 15
The lever 15g is configured to receive a pressing force from one end of the lever 15g, which swings around the lever 6 as a fulcrum. The other end of the lever 158 is engaged with a groove provided on the outer periphery of the movable conical plate 44 of the drive pulley 6. Therefore, when the gear ratio increases, the sleeve 15
0 moves to the right in the figure, and as the gear ratio becomes smaller, the sleeve 150 moves to the left in the figure. two springs 152
Of the springs 152 and 154, the outer spring 152 is always in a compressed state with both ends in contact with the sleeve 150 and the spool 148, respectively, but the inner spring 154 is compressed when the sleeve 150 moves more than a predetermined amount to the right in the figure. This is the first time it has been compressed. The bow) 146a of the line pressure regulating valve 102 is connected to the speed change control valve 106 through an oil passage 160.
It is connected to port 172a of. Throttle pressure is supplied to the port 146b from an oil passage 162, which is a throttle pressure circuit. The port 146c communicates with an oil passage 164 that is a lubrication circuit. Ports 146d and 146e
Line pressure is supplied from an oil passage 132, which is a line pressure circuit. 146f is the drain port 1. Note that orifices 166, 168, and 170 are provided at the inlets of ports 146a, 146b, and 146e, respectively. In the end, the spool 1 of this line pressure regulating valve 102
48 includes the force exerted by the spring 152 (or the force exerted by the springs 152 and 154), the force exerted by the hydraulic pressure of the port 146a on the area difference between the lands 148a and l'48b, and the hydraulic pressure of the port 146b (thrower pressure). three rightward forces acting on the area difference between lands 148b and 148a, and the hydraulic pressure (line pressure) of port 146e acting on the area difference between lands 148d and 148a.
The force between the left and right sides of spool 1 acts on the spool 1.
48 is the port 1 which adjusts the amount of oil leaking from the port h146d to the port 146c so that the force in the left and right direction is always balanced.
-146 Control the line pressure of e. Therefore, the line pressure increases as the gear ratio increases, and the higher the oil pressure of the port l-146a (this oil pressure acts only during sudden gear changes as described later, and is the same oil pressure as the line pressure), the higher the line pressure becomes. ) The higher the throttle pressure acting on 146b, the higher the throttle pressure. To adjust the line pressure in this way, the larger the gear ratio, the greater the pulley's pushing force against the V belt.
In addition, it is necessary to rapidly supply oil to the pulley cylinder chamber during sudden gear changes, and when the throttle pressure is high (that is, the negative pressure in the engine intake pipe is small), the engine output and torque are large, so the oil pressure is increased and the pulley cylinder chamber is supplied with oil. This is to increase the V-belt pressing force and increase the power transmission torque due to friction.

The speed change control valve 106 has four ports 172a and 172b.
, 172c and 172d; a spool 174 having three lands 174a, 174b and 174c corresponding to the valve holes 172;
．． It consists of a spring 175 that pushes to the left in the figure. As described above, the port 172a communicates with the port 146a of the line pressure regulating valve 102 via the oil passage 160, and the port 172b communicates with the oil passage 132, which is a line pressure circuit, and is supplied with line pressure. , the land 172c is connected to the port I/2 of the maximum gear ratio holding valve 120 via the oil passage 176.
30d, and the port 172d communicates with an oil passage 164, which is a lubrication circuit. In addition, Poe) 172
An orifice 177 is provided at the inlet of d. The left end of the spool 174 is connected to the lever 17 of the speed change operation mechanism 112, which will be described later.
8 by a pin 181.

The axial length of land 174b is somewhat smaller than the width of port 1-1720. Therefore, the line pressure supplied to the port 172b passes through the gap between the left side portion of the land 174b and the port 172c.
A part of it flows into the port (172C) from the gap between the right side of the land 174b and the port (172C).
d, the pressure at port 172c is determined by the area ratio of the side gaps.

Therefore, as the spool 174 moves to the right, the clearance on the line pressure side of port '172c becomes larger and the clearance on the discharge side becomes smaller, so that the pressure in port 172C gradually increases. The oil pressure of the port 172C is transmitted to the drive pulley cylinder chamber 4 through the oil passage 176, the maximum gear ratio holding valve 120 (lower half shown in the figure), and the oil passage 180.
2. Therefore, the pressure in the drive pulley cylinder chamber 42 of the drive pulley 6 becomes high and the width of the V-shaped pulley groove becomes small, and on the other hand, line pressure is always supplied to the driven pulley cylinder chamber 56 of the driven pulley 51 through the oil passage 132. However, since the pressure receiving area of the driven pulley cylinder chamber 56 is approximately 1/2 of the pressure receiving area of the driving pulley cylinder chamber 42, the V belt pressing force is relatively small compared to the driving pulley 6 side. The width of the groove in the shaped pulley becomes larger. That is, the V-belt contact radius of the drive pulley 6 becomes larger and the V-belt contact radius of the driven pulley 51 becomes smaller, so that the gear ratio becomes smaller. Conversely, when the spool 172 is moved to the left, the gear ratio increases due to the completely opposite effect to the above.

As described above, the lever 178 of the speed change operation mechanism 112 is connected to the spool 174 of the speed change control valve 106 at approximately the center thereof.
is connected to the lever 178 by a pin 181.
One end is connected to the end of the lever 158 on the side that contacts the sleeve 150 by a pin 183 (for reasons of illustration), the pin 183 on the lever 158 and the pin 183 on the lever 178 are Although shown separately, they are actually the same member), and the other end is the rod 1
82 by a pin 185.

The rod 182 has a rack 182c, and this rack 182C is connected to the pinion gear 110a of the variable speed motor IIO.
They are interlocked. In such a speed change operation mechanism 112, when the rod 182 is moved, for example, to the right by rotating the pinion gear 110a of the speed change motor 110 controlled by the speed change control device 300, the lever 1
78 rotates counterclockwise about the pin 183 and connects to the spool 1 of the speed change control valve 106 connected to the lever 178.
Move 74 to the right. With this, as mentioned above,
The movable conical plate 44 of the drive pulley 6 moves to the right, the V-shaped pulley groove interval of the V-shaped pulley groove pulley 51 of the drive pulley 6 becomes larger, and the gear ratio becomes smaller. One end of the lever 178 is connected to the lever 158 by a pin 183, so when the movable conical plate 44 moves to the right and the lever 158 rotates counterclockwise, the
The lever 178 rotates counterclockwise using the pin 185 at the other end of the lever 78 as a fulcrum. Therefore, the spool 174 is pulled back to the left, and the driving pulley 6 and the driven pulley 51
Trying to make the gear ratio larger. Through such operations, the spool 174, drive pulley 6, and driven pulley 51 are stabilized at a predetermined speed ratio corresponding to the rotational position of the speed change motor 110. The same is true when the speed change motor 110 is rotated in the opposite direction (note that the rod 182 can move further to the left (overstroke area) in the figure beyond the position corresponding to the maximum speed ratio; When the shift reference switch 298 is activated,
This signal is input to the speed change control device R300). Therefore, when the speed change motor 110 is operated according to a predetermined speed change pattern, the speed change ratio changes accordingly, and by controlling the speed change motor 110, the speed change of the continuously variable transmission can be controlled.

Note that when the speed change motor 110 is rapidly operated to the larger speed ratio side, the spool 174 of the speed change control valve 106 is temporarily moved to the left side in the figure (however, as the speed change progresses, it gradually returns to the center position). ). When the spool 174 moves significantly to the left, the ports 172a and 172b communicate between the lands 174a and 174b, and line pressure is supplied to the oil passage 160. The line pressure in the oil passage 160 acts on the port 146a of the line pressure regulating valve 106, increasing the line pressure as described above. That is, when the gear ratio is rapidly changed to the larger gear ratio side, the line pressure becomes higher. by this,
Oil can be rapidly fed into the driven pulley cylinder chamber 56 to quickly change gears.

Variable speed motor (in the following explanation, "step motor")
) 11o is the transmission control device 300
The rotational position is determined in response to the pulse number signal sent from. The pulse number signal from shift control device 300 is given according to a predetermined shift pattern.

The clutch complete engagement control valve 108 has a valve body integrally formed with the rod 182 of the speed change operation mechanism 112. That is, the clutch complete engagement control valve 108 is connected to the port 186a.
and 186b, and lands 182a and 182b formed on the rod 182. The port 186a communicates with the aforementioned pitot tube 48 through an oil passage 188. That is, a signal hydraulic pressure corresponding to the rotational speed of the drive pulley 6 is supplied to the port 186a. The port 186b communicates with the port 204e of the starting valve 116 via an oil passage 190. Typically, ports 186a and 186b are connected to lands 1B2a and 1
However, only when the rod 182 moves beyond the position corresponding to the maximum speed ratio (the position where the speed change reference switch 298 is turned on) and moves into the overstroke region, the port 186a is closed and the port 186a is closed. 1-18
6b is to be drained. That is, the clutch complete engagement control valve 108 normally controls the rotation speed signal oil pressure of the drive pulley 6 to the starting valve 116 (7) ball l.
-204e, and has a function of stopping the supply of the signal hydraulic pressure when the rod 182 exceeds the maximum gear ratio position and moves to the overstroke region.

The throttle valve 114 has ports 192a, 192b, 1
a valve hole 192 having 92c, 192d and 912e;
Three lands 194a, 194b corresponding to the valve hole 192
and 194c, and spool 19
Spring 196 that pushes 4 to the right side in the figure, and spool 19
4 and a negative pressure diaphragm 198 that applies a pushing force to Negative pressure diaphragm 198 applies a force inversely proportional to the negative pressure to spool 194 when engine intake pipe negative pressure is lower than a predetermined value (for example, 300 mmHg) (close to atmospheric pressure), If the value is higher than t± no force is applied. baud)
192a communicates with an oil passage 164 which is a lubrication circuit,
Ports 192b and 192d communicate with an oil passage 162 which is a throttle pressure circuit, and port 192c communicates with an oil passage 132 which is a line pressure circuit.
92e is a drain port. An orifice 202 is provided at the entrance of bow 1-192d. Spool 19
4 includes the force of the spring 196 and the negative pressure diaphragm 1
98, which is a force directed to the right in the figure, and the land 194b.
Although a force directed to the left in the figure, the force due to the hydraulic pressure of 192cl, which acts on the area difference between -) 192a is used as a discharge boat to perform a well-known pressure regulating action. As a result, a throttle pressure corresponding to the force exerted by the spring 196 and the negative pressure diaphragm 198 is generated at the bows 192b and 192d. The throttle pressure obtained in this way is regulated according to the engine intake pipe negative pressure, so
Corresponds to engine output torque. That is, if the engine output torque is large, the throttle pressure also becomes a correspondingly high oil pressure.

The starting valve 116 is BO) 204a, 204b.
, 204C1204d and 204e
and lands 206a, 206b, 206C and 206d
The spool 206 is made up of a spool 206 (note that the left side portion of the land 206a in the figure is tapered in diameter) and a spring 208 that pushes the spool 206 to the right in the figure. The ball 1-204a communicates with an oil passage 140 that is connected via an orifice 210 to an oil passage 162 that is a throttle pressure circuit. 204b is drained via an oil passage 200 (this oil passage communicates between the oil pump IO and the strainer 131), which is a drain circuit. Port 204c is connected to start adjustment valve ti8 via oil passage 212. 204d communicates with the pitot tube 20 described above through an oil passage 214.

That is, a signal hydraulic pressure corresponding to the rotational speed of the input shaft 2 (that is, an engine rotational speed signal hydraulic pressure) is supplied to the port 204d. As described above, the port 204e communicates with the bow 1-186b of the clutch full engagement control valve 108 through the oil passage 190. Orifices 216, 218, and 220 are provided at the inlets of ports 204c, 204d, and 204e, respectively. The starting valve 116 has a function of discharging oil from the ports 204a and 204b to the ports 204b according to the position of the spool 206, thereby making the oil pressure (starting pressure) in the oil passage 140 lower than the throttle pressure.

That is, when the spool 206 is located toward the left in the figure, the clearance from the bow 204a to the port 204b is small, so the oil pressure at the bow 204a is high, and conversely, when the spool 206 moves to the right in the figure, the oil pressure at the port 204a is high. The clearance from the bow h204b to the bow h204b increases, the amount of oil leakage increases, and the oil pressure at the port 204a decreases. Note that since the oil passage 162, which is the throat I/le pressure circuit, and the oil passage 140, which is the start pressure circuit, are connected through the orifice 210, even if the oil pressure in the oil passage 140 becomes low, the throat )・Le pressure is virtually unaffected. Spool 2
The position of 06 is due to the force of the spring 208 and the land 206.
A rightward force due to the hydraulic pressure (start adjustment pressure) that acts on the area difference between lands 206C and 206c, and a force due to the hydraulic pressure (engine rotation speed signal hydraulic pressure) of port 204d that acts on the area difference between lands 206C and 206a and the land. 20
It is determined by the balance with the leftward force of the oil pressure (drive pulley rotation speed transformation - 5 oil pressure) of the bow) 204e acting on the motor 6d. That is, the higher the start adjustment pressure in the oil passage 212 obtained by the start adjustment valve 118 (described later), the lower the start pressure in the oil passage 140, and the higher the engine rotation speed signal oil pressure and the drive pulley rotation speed signal oil pressure, the higher the start pressure. Become. At the time of starting, the rod 182 of the clutch complete engagement control valve 108 is moved to the far left, and the oil passage 190 is drained, so the drive pulley rotation speed oil pressure signal is sent to the port 204e of the starting valve 116. is not working. Therefore,
The start pressure is controlled by the start adjustment pressure and the engine speed signal oil pressure, and gradually increases as the engine speed increases. This start pressure is supplied to the forward clutch 4 (or the reverse clutch 24), which is gradually engaged to enable a smooth start.

When the start progresses to a certain extent, the clutch full engagement control valve 108 is switched by the action of the step motor 11O, and the drive pulley rotation speed signal oil pressure is supplied to the port 204e via the oil path 190, and the start pressure increases rapidly. As a result, the forward clutch 4 (or the reverse clutch 24
) are securely fastened and there is no slippage. Note that since the starting valve 116 regulates the throttle pressure according to the engine output torque supplied to the port 204a and supplies it to the forward clutch 4 and the reverse clutch 24,
Unnecessarily high oil pressure does not act on the forward clutch 4 and the reverse clutch 24. This is suitable for the durability performance of the forward clutch 4 and the reverse clutch 24.

The start adjustment valve 118 is connected to the oil port 22 of the oil passage 212.
2 (This port 222 is connected to the oil passage 200 which is a drain circuit.
The force smoke 224 is configured by a force smoke 224 whose discharge amount to the cylinder (which is in communication with the cylinder) can be adjusted by a plunger 224a. Low-pressure oil is supplied to the oil passage 212 from an oil passage 164, which is a lubricating oil passage, through an orifice 226.

The force smoke 224 is inversely proportional to the amount of current flowing through the oil path 224.
In order to discharge the oil of No. 12, the oil pressure (start adjustment pressure) of the oil passage 212 is controlled by the amount of energization.

The amount of current applied to the force smoke 224 is controlled by the speed change control device 300. When the vehicle is in an idling state where the vehicle is stopped, the start pressure (hydraulic pressure regulated by the starting valve 116) is applied to the forward clutch 4 by the start adjustment pressure obtained by the start adjustment valve 118.
Alternatively, the reverse clutch 24 is controlled to be in a state immediately before starting engagement. Since this start pressure is always supplied to the forward clutch 4 or reverse clutch 24 before starting, the forward clutch 4 or reverse clutch 24 starts to engage immediately as the engine speed increases, and the engine speed increases. There is no possibility of engine racing, and even if the engine's idling speed is higher than normal, there will be no false start.

The maximum gear ratio holding valve 120 is 230a, 230b.
, 230c, 230d, 230e and 230f, and lands 232a, 232b and 232c.
It consists of a spool 232 having a spool 232 and a spring 234 that pushes the spool 232 to the left in the figure. port 2
The drive pulley rotation speed signal oil pressure is led from the oil passage 188 to the port 30a, and the port 230c is connected to the drive pulley cylinder chamber 42 and the reverse inhibitor valve 1 by the oil passage 180.
It communicates with the port 240d of 22, and also the port 240d of
0d is the port 1 of the speed change control valve 106 via the oil passage 176.
It communicates with 72c. The port 230b is drained via the oil passage 200, and the port 230f is a drain port. Orifices 236 and 238 are provided at the inlets of bows 230a and 230e. Land 232
a and 232b have the same diameter, and land 232C has a smaller diameter than these. This maximum gear ratio holding valve 120 is a valve that achieves the maximum gear ratio at the time of starting regardless of the state of the gear change control valve 106. As a result, even if the speed change control valve 106 is fixed at the small speed ratio side due to a failure of the step motor 110 or the like, it is possible to start the vehicle in the maximum speed ratio state. When the vehicle is stopped, the drive pulley rotation speed signal oil pressure is O, so there is no force pushing the spool 232 to the right in the figure, and the spool 232 is pushed by the spring 234 to the state shown in the upper half of the figure. It is in. Therefore, the drive pulley cylinder chamber 42 is drained through the oil passage 180, port 230c, port 230b, and oil passage 200, and the continuously variable transmission is always in the maximum gear ratio state. In this state, the land 232a of the spool 232
The force directed to the right in the figure due to the hydraulic pressure of the bow (bow) 230a (drive pulley rotation speed signal hydraulic pressure) acting on the area of the land 232
This is maintained until it overcomes the leftward force of the force due to the oil pressure (engine rotation speed signal oil pressure) of the port 230e (engine speed signal oil pressure) and the force due to the spring 234 (which acts on the area difference between 230e and 232a). That is, the maximum gear ratio remains until the forward clutch 4 starts to be engaged and the drive pulley 6 starts rotating at a certain speed (that is, the slippage of the forward clutch 4 becomes small). When the drive pulley 6 begins to rotate at a speed higher than a predetermined speed, the maximum gear ratio holding valve 120 switches to the position shown in the lower half of the figure (bow) 230c and 230d.
As a result, hydraulic pressure from the speed change control valve 106 is supplied to the drive pulley cylinder chamber 42, and the continuously variable transmission becomes able to change speed. Spool 2 of maximum gear ratio holding valve 120
32 is in the state shown in the lower half of the figure, the hydraulic pressure that was acting on the area difference between the lands 232b and 232a is drained from the port 230f, so that the spool 23
2 does not return to the position shown in the upper half until the drive boolean rotation speed signal oil pressure becomes very low. That is, just before the vehicle speed becomes very low and the vehicle stops, the spool 232 returns to the position shown in the upper half and enters the maximum gear ratio state. Note that the drive pulley rotation speed signal oil pressure is O when the drive pulley 6 is rotating in the opposite direction (that is, when the reverse clutch 24 is operating), so it is always at the maximum value even when reversing. It will be in the gear ratio state.

The reverse inhibitor valve 122 has ports 240a, 2
a valve hole 240 having 40b, 240c and 240d;
Spool 2 with lands 242a and 242b of equal diameter
42, and a spring 244 that pushes the spool 242 to the right in the figure. The port 240a is a drain port, the port 240b communicates with the piston chamber 38 of the reverse clutch 24 via an oil passage 144, and the port 240C communicates with the port 134b of the manual valve 104 via an oil passage 138. The port 240d is connected to an oil passage 180 that supplies hydraulic pressure to the drive pulley cylinder chamber 42-1. This reverse inhibitor valve 122 is
This valve prevents the reverse clutch 24 from operating when the manual valve 104 is mistakenly selected to the R position during forward travel. When the vehicle is stopped, the hydraulic pressure in the oil passage 180 (that is, the drive pulley cylinder chamber 42) is drained by the action of the maximum gear ratio holding valve 120 described above. Therefore, since no leftward force in the figure acts on the spool 242 of the reverse inhibitor valve 122, the spool 242 is pushed by the spring 244 to the position shown in the upper half of the figure, and the bows 240b and 240C are in communication. There is. When the manual valve 104 is selected to the R position in this state, the hydraulic pressure of the bow 134b of the manual valve 104 is supplied to the piston chamber 38 of the reverse clutch 24 via the oil passage 138, port 240C, port 240b, and oil passage 144. Ru. As a result, the reverse clutch 24 is activated, and the vehicle enters the reverse state.

However, while the vehicle is moving forward, the maximum gear ratio holding valve 120
is in the position shown in the lower half of the figure until just before it stops, and the oil passage 18
0 is supplied with hydraulic pressure from an oil passage 176. This oil pressure is the port 2 of the reverse inhibitor valve 122! Since it acts on LOd, the reverse inhibitor valve 122 is in the state shown in the lower half of the figure, communication between the oil passages 138 and 144 is blocked, and the oil pressure in the piston chamber 38 of the reverse clutch 24 is drained from the port 240a. . Therefore, in this state, even if the manual valve 104 is selected to the R position, no hydraulic pressure is supplied to the piston chamber 38 of the reverse clutch 24. This can prevent the power transmission mechanism from moving backward and being damaged during forward travel.

The lubrication valve 124 has ports 250a, 250b, and 250C.
and a valve hole 250 with 250d and a land 2 of equal diameter.
It consists of a spool 252 having 52a and 252b, and a spring 254 that pushes the spool 252 to the left in the figure. The port 250a is connected to an oil passage 164 that communicates with the downstream side of the cooler 260, and the port 250b is connected to an oil passage 162 that is a throttle pressure circuit.
250c is an oil passage 2 that communicates with the upstream side of the cooler 260.
58, and the port 250d is connected to an oil passage 200 which is a drain circuit. This lubricating valve 124
The throttle pressure of the port 250b is used as the hydraulic pressure source, and the hydraulic pressure of the port 250a is controlled by the spring 2 by a well-known pressure regulating action.
54 and supplies it to the oil path 164. The oil in the oil passage 164 is used to supply and lubricate the rotary grooves 16 and 46, and then is transferred to the tank 130.

Next, the increase in line pressure during a sudden shift due to the actions of the line pressure regulating valve 102, the shift control valve 106, the step motor 110, and the shift operation mechanism 112 will be summarized again.

When the accelerator pedal is pressed rapidly, the shift control device 30
0 gives an operating signal to the step motor 110 to rapidly rotate the pinion gear 110a toward the larger gear ratio side. Therefore, the spool 174 of the speed change control valve 106 is connected to the speed change operation mechanism 1.
12, it is temporarily moved to the left side in the figure. When the spool 174 moves significantly to the left, the port 172a
and 172b are land 174. λ and 174b communicate with each other, and line pressure is supplied to the oil passage 160. The line pressure of the oil passage 160 acts on the port 146a of the speed change control valve 106 and applies a force to the spool 148 in the right direction in the figure. This increases line pressure. That is, the line pressure increases when the gear ratio is rapidly changed to the larger gear ratio side. Note that the spool 174 of the speed change control valve 106 gradually returns to a stable position due to the action of the speed change operation mechanism 112, so after a certain period of time, the supply of line pressure to the oil passage 160 is stopped.
Line pressure returns to normal value. The temporary increase in line pressure causes oil to be rapidly fed into the driven pulley cylinder chamber 56, resulting in rapid gear changes, improving gear change response and preventing slippage of the V-belt.

As described above, according to the present invention, a V-belt is wound around the drive pulley and the driven pulley, the distance of which is variable between the figure-7 grooves in accordance with the oil pressure in the pulley cylinder chamber controlled by the speed change control valve. In the line pressure control system of a V-belt type continuously variable transmission that transmits power by Since it is connected to the pressure increase port of the line pressure regulating valve, it prevents slippage of the V-belt and improves shift response.In addition, the shift control valve can be made smaller, and the valve hole of the iE shift control valve The effect is that the workability of the spool can be improved.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional shift control rod valve, Figure 2 is a diagram showing the control valve shown in Figure 1 with the spool moved to the right, and Figure 3 shows changes in oil pressure during gear shifting. The figure shown in Figure 4 is V
FIG. 5 is a diagram showing the power transmission mechanism of the belt type continuously variable transmission, and FIG. 5 is a diagram showing the hydraulic control device. 2...Input shaft, 4.Forward clutch, 6..Φ drive pulley, 8..drive shaft, 10..oil pump,
120 race・Drive gear, 14・φ・Driven gear, 16・・One rotation, 18・・Oil pool, 20・・φ Pitot tube,
22... Subshaft, 24... - Reverse clutch, 26.28
, 30, 32.34-・φ key, 36.38・・reference piston chamber, 40・・φ fixed conical plate, 42・φ・driving pulley cylinder chamber, 44・・・movable conical plate, 46φ,・
Rotating channel, 47・φ・oil pool, 48... Pitot tube,
50...V belt, 51...driven pulley, 52Φ-
- Driven shaft, 54 - fixed conical plate, 56 - driven pulley cylinder chamber, 57 - spring, 58 - Φ movable conical plate, 60 - gear, 62 - fist ring gear,
64 fist...differential case, 66.68...pinion gear, 70...differential gear, 72.74@--side gear,
76.78... Output shaft, 102... 9-line pressure regulating valve, 104... Manual valve, 106... Speed change control valve,
108... Clutch complete engagement control valve, 110, Φ, speed change motor, 112... Speed change operation mechanism, 114... Throttle valve, 116... Sz-mating valve, 118
φφ fist start adjustment valve, 120... Maximum gear ratio holding valve, 122 life... Reverse inhibitor valve, 124Φ...
Lubricating valve, 130...Tank, 131--Strainer, 132--Oil passage, 134--Valve hole, 136--
Spool, 138, 140.142.144 Fist/Oilway, 148eφ/Spool, 150...Sleeve, 15
2,154 Lu・Φ Spring, 156 Mass. Pin, 15
8.11-Lever, 160.162.164...Fist oil passage, 166.168,170-...Orifice, 172.
#Kisten valve hole, 174--Kist spool, 175φ, spring, 176...Oil passage, 178, φ, lever, 180
・Φ oil road, 181.183.185・war・pin, 18
2 fists/working rod, 190... oil path, 192 fists... valve hole, 194... spool, 196... spring, 1
98 pot/house negative pressure Guyafram, 200@φ/oil line, 20
2・Clear・Orifice, 204#-ψ valve hole, 206-・-
Spool, 208...Spring, 212', 214
Number... Oil passage, 216, 218, 220@... Orifice, 224 Yu... Force smoke, 226 Φ conflict, Orifice, 232... ψ Spool, 23411... Spring, 242... Φ Spool, 244... Spring ,2
50...Valve hole, 252...e spool, 254Φ...
Spring, 258... Oil path, 260... Cooler,
298... Speed change reference switch, 300... Speed change control device.

Claims (1)

[Scope of Claims] A V-belt type device that transmits power by wrapping a V-belt I around a driving pulley and a driven pulley whose V-shaped groove spacing is variable according to the oil pressure in a pulley cylinder chamber controlled by a speed change control valve. In a line pressure control device for a step change transmission, a port to which line pressure is supplied when the spool of the speed change control valve is displaced by a predetermined amount or more in the direction of increasing the gear ratio is
A line pressure control device for a V-belt continuously variable transmission, characterized in that it is connected to a pressure increasing port of a line pressure regulating valve.