JPS604660A - Hydraulic controller for continuously variable transmission associated with electromagnetic clutch - Google Patents

Abstract

PURPOSE:To improve the fuel consumption by providing a bypath between a line pressure circuit and a lubrication circuit at the drain pressure side while providing a valve openable upon interruption between an engine and transmission and a check valve in the bypath. CONSTITUTION:A bypath 62 is provided between a line pressure circuit 39c at the delivery side of an oil pump and a lubrication circuit 61, while a valve 63 openable upon interruption between the engine and transmission and a check valve 64 for setting the line pressure higher than the lubricant pressure are provided in series. Consequently, even if the speed change ratio is at the maximum under idling, the delivery pressure and the driving load of the oil pump can be reduced, resulting in stabilization of idling operation and improvement of fuel consumption.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a 71M dual-purpose electromagnetic clutch 1 continuously variable transmission.
3. Regarding the hydraulic pressure-01B system that automatically performs stepless speed change control while converting the bell mill pulley ratio, especially when the operating source is an oil pump that is directly driven by the engine, during no-load operation such as idling, etc. Related to reducing engine negative effects associated with oil pump drive.

Regarding the hydraulic control system for this type of continuously variable transmission, conventionally, for example, Japanese Patent Application Laid-open No. 54-157930, Japanese Patent Application Laid-open No. SG-66
There is a prior art in each publication of No. 553, which acts on the auxiliary pulley side while regulating the discharge oil pressure of the oil pump with a pressure regulating valve, and also works on the speed change control valve that operates depending on the relationship between the throttle trace and the engine speed. It is configured to also act on the pulley side to control the pulley ratio, that is, the gear ratio. Especially in the pressure w4 valve, the line pressure is increased at low speeds where the transmission torque is large and the pulley Lt is large, as shown by the solid line in Figure 3, depending on the relationship between the actual gear ratio, sub-pulley servo oil pressure, and engine speed. <<C> Adjust the line pressure so that it decreases as you move to the high speed stage. The pulley pressing force required to transmit the maximum torque of the engine at each gear ratio, that is, the mutual frictional force between the belt and the pulley is obtained.

So C, to explain using idling driving as an example, 12
222 rotation speed is very low, and the gear ratio is maximized by setting the gear shift control valve to 1:1.
The line pressure is maximized due to the small pressure regulating valve, and the pump driving load is the highest. Therefore, in the case where the A-il pump is directly driven by the engine, the above-mentioned pump drive load is large in the state where the first engine output is small during idling, and the pump drive load is supplemented to maintain stable idling operation. As such, it is necessary to increase the opening degree of y, ""i: + liter, which causes a problem of poor fuel efficiency.

<r 63. Another example of no-load operation is when the shift lever is set to the neutral 1 position while the vehicle is running and the vehicle coasts to -C, which is represented by the word idling.

The present invention solves the problems associated with the speed change control of the maximum speed ratio during idling when d3 < d3, and the present invention solves the problem of controlling the speed change at the maximum speed ratio during idling when d3 < d3. An object of the present invention is to provide a hydraulic control device for a continuously variable transmission equipped with an electromagnetic clutch, which is capable of stabilizing engine idling operation and improving fuel efficiency by reducing the driving load.

For this purpose, the device according to the present invention, in a continuously variable transmission equipped with an electromagnetic clutch, automatically disengages the electromagnetic clutch depending on the vehicle speed and whether or not the accelerator pedal is depressed before driving or when idling just before stopping during deceleration. Power is no longer transmitted in the N (neutral) range, and as a result, during this idle link, the pressure required for torque transmission (= J
Focusing on the fact that there is no need for high line pressure to maintain the oil pressure, and that it is necessary to maintain the specified lubrication oil pressure even during idling, we developed a new system between the line pressure circuit on the oil pump outlet side and the drain side lubrication circuit. An on-off valve and a check valve are installed in a bypass circuit connected to The purpose is to reduce the discharge pressure and drive load of the delta pump while ensuring a predetermined lubricating oil pressure.

An embodiment of the present invention will now be described in detail with reference to the drawings. First, in Fig. 1, an example of a continuously variable transmission with an electromagnetic clutch to which the present invention is applied is explained.The C1 continuously variable transmission with an electromagnetic powder clutch is explained. The continuously variable transmission tM2 is roughly divided into 4Rs, including a forward/reverse switching section 3, a belt type continuously variable transmission section 4, a final reduction section 5, and a hydraulic control section 6.

The electromagnetic powder clutch 1 is connected to the crank @1 from the engine.
The drive member 9 with built-in gear 8 is integrally connected, and the driven member 1 is connected to the gear shift 1, which has a built-in power of 11?1110.
1 is integrally spline-coupled in the rotational direction, and these drives and driven members 9, 11 are connected to the 1'11 tube 12
M is fitted through the gap 12, and electromagnetic powder is collected from the balata chamber 13 in this gap 12.

A slip ring 15 is installed on the drive member 9 via a holder 14, and a power supply brush 1G is in sliding contact with the slip link 15 to prevent clutch current from flowing through the coil 8.

As a result, electromagnetic particles are combined in a chain shape and accumulated in the gap 12 between them due to the lines of magnetic force generated between the clutch current J and the drive and driven members 9 and 11. The driven member 11 slides against the drive member 9 due to the force and becomes integrally connected to the drive member 9. On the other hand, when the clutch current is cut, the coupling force between the drive and the driven member 9.11 due to the electromagnetic powder disappears, and the clutch becomes disconnected. In this case, if the clutch current is supplied and cut in conjunction with the operation of the switching section 3 of the continuously variable transmission 2 using a shift lever, etc., the clutch current can be switched to P (parking) or N (natural) range. When switching from the D (drive), L (low), or (((reverse)) range, the clutch 1 is automatically connected and disconnected, making it unnecessary to operate the clutch pedal.

Next is continuously variable speed 4! ! 2, the switching section 3 is shifted between the input shaft 10 from the clutch 1 and the main shaft 17 of the continuously variable transmission section 4 disposed coaxially therewith, and is connected to the reverse drive shaft integrally connected to the input shaft 10. The reverse drive gear 18 and the reverse driving gear 1/19, which are rotatably fitted to the main shaft 11, are connected via the counter gear 20 and idler gear 21 to
These main shafts 17 and 118.
During the period 19, the switching clutch 22 is engaged.

Then, the main shaft 17 is directly connected to the input shaft 10 by engaging the switching clutch 22 to the gear 718 side from the neutral position 1i'l of the N range, and the main shaft 17 is directly connected to the input shaft 10. When engaged with gear X719 side, input shaft 1
The V-no-nono at 0 is decelerated and reversed by gears A718 to 21, and enters the reverse state in the 'UR range.

The continuously variable transmission section 4 has a sub 111b2 for the child 111117.
3 are arranged in parallel, and a main pulley 24 and a sub-pulley 25 are provided on both shafts 17 and 23, respectively, and the pulley 2
During the period of 4.25, the L-endless drive bell 1-26 was turned off. Pulley 24.25 is divided into 2 parts and 4i.
ii1 moving side pulley 141i 24a,
At 25a, oil 73 and 17-bore devices 27 and 28 are arranged in one stage to make the pulley interval variable.

Therefore, in this case, the main pulley 24 moves the movable side pulley 24a closer to the stationary side boob 9 (body 9) [the boob interval is gradually narrowed, and the sub pulley 251 moves in the opposite direction. The movable half-boot half 25a acts in a direction away from the fixed half-boot 251), thereby changing the winding f dimension (the ratio of the pulley diameters) of the pulley 24.25 of the drive belt 26. The power is taken out to sub@23.

In the final reduction section 5, a large-diameter final gear 32 meshes with an output gear 31 of an output shaft 30 connected to the side @ 23 via an intermediate reduction gear p29, and a large-diameter final gear 32 meshes with an output gear 31 of an output shaft 30 connected to the side @ 23 via an intermediate reduction gear p29. The power is transmitted to the axles of the left and right drive wheels (marked at 34°).

Furthermore, the hydraulic control section 6 is connected to the main pulley 24 side, passing through the main shaft 17 and the input shaft 10, and a hydraulic pump is connected to the pump drive shaft 3G, which is directly connected to the engine crank @ 7, so that hydraulic pressure is always generated during engine operation. 37 is installed.Then, this pump oil pressure is controlled by the oil pressure control circuit 38 according to the throttle opening degree, engine rotation speed, etc.
0 to each hydraulic cylinder on the main pulley and sub pulley side @2
41 (supplied at 1.28), and is configured to perform continuously variable speed control of the continuously variable transmission section 4.

To explain the speed change control system in FIG. 2, in the hydraulic υ-bo device 27 on the main pulley side, the main pulley 1 sliding side body 24a serves as a piston and is connected to the sea cylinder 27a.
I & L, the line of the servo chamber 27b is set to operate, and in the sub-pull side hydraulic pressure υ=-bo device 28, the sub-boot movable side half-rest 25a is brought into contact with the cylinder 28a,
The line pressure of the servo chamber 28b operates, and in this case, the half-rest 24a has a larger line pressure receiving area than the half 25a. The oil passage 40 from the C1 sub-pulley l nervous chamber 28b is connected to the oil reservoir 4 via an oil pump 37 directly driven by the engine and a filter 41.
2, and branches from the oil pump discharge side of this oil passage 40 and communicates with the main pulley nervo chamber 271+.
9 is provided with a pressure regulating valve 43 and a speed change control TA11 valve 44.

- The speed change control valve 44 is a valve body 45. It consists of a spool 46, a spring 47 biased to one side of the spool 46, and an actuating member 48 that changes the spring force. Rotation tip 4 that detects the engine rotation speed
The pitot 11 from 9 is moved through the oil passage 50, and the actuating member 48 is in contact with a spot cam 51 that rotates in accordance with the throttle distance 1. Also, the boat 45b of the valve body 4;i is the land 46a of the spool 4G.

46b selectively communicates with one of the line pressure supply ball l-45c and drain ball l-45d, and the port 451) is connected to the valve chamber 27b by the oil passage 39a. Communication, boat, g 45c is oil path 3
9b communicates with the pressure regulating valve 43 side, drain bow 1=
4! id is connected to the oil reservoir side by an oil passage 52.

As a result, in the spool 46 of the speed change control valve 44, the pitot pressure and the □
, and a spring force corresponding to the throttle opening degree accompanying the rotation of the torque cam 51 act against each other, and the operation is based on the relationship between these two forces. In other words, the higher the engine speed, the smaller the opening of the boat 451) and 45.
c is in communication and the line pressure is introduced into the main boolean reservoir chamber 271), so the gear ratio is reduced and the gear is shifted to the high speed side.

Next, the pressure regulating valve 43 is turned on! 3, spool 5
4. The spring 55 has one arm, and the pitot pressure of the oil passage 5 () and the line pressure from the oil passage 39 are introduced to the boats 53a and 53b on the opposite side of the spring 55, respectively, and the spring 55 Main pulley movable side half rest 2
A feedback link 5G is connected to the transmission gear 4a and detects the actual gear ratio. Furthermore, the oil passage 39c on the pump side
is always in communication with the oil passage 391+ on one side of the speed change control regardless of the position of the spool 54. In addition, the oil passage 52b1 on the drain side is in communication with the boat 53 (IL).The spool 54 moves slightly from side to side due to the pitot juice and the force of the spring. By controlling the communication between the port 53c and the drain side oil passage (2), the line pressure can be regulated.

As a result, the spool 54 of the pressure regulating valve 43 has a bit
The added force of the twin pressure and the spring force corresponding to the actual gear ratio act against each other, resulting in the relationship shown in I). That is, when the engine speed increases, the pitot pressure increases, or the gear ratio shifts to the high speed side and the force pushing the spring 55 of the feedback link 56 decreases, the pitot pressure increases and the squirrel spool 54 moves to the left side. The force pushing the spool 54 to the right increases or the spring 5 pushes the spool 54 to the right.
5 force is reduced and the lower line pressure causes the spool 5 to
4 moves to the left side, the oil passage 39c and the oil passage 52 communicate with each other, and the line pressure is regulated so as to decrease by partially draining, and the line pressure is reduced to the required oil pressure on the gear side. Decrease.

In addition, when the main pulley servo chamber 27b is drained by the shift control valve 44 due to the effect of the throttle force 1151 accompanying the full opening of the thrower during kickdown or a decrease in engine speed, the feedback link is activated. 5
6 increases the spring load of the pressure regulating valve 43, closes the communication from the oil passage 39c to the oil passage 52, and adjusts the auxiliary pulley lever hydraulic pressure to a high level, making it the required line pressure on the lower speed stage side. . Then, a pulley pressing force that does not cause belt slip is obtained with respect to the transmission torque corresponding to each gear ratio between the low speed gear and the high speed gear.

In such a configuration, the drain oil path 52 is further connected from, for example, the oil path 39c of the discharge side line pressure circuit of the oil pump 31.
A bypass oil passage 6 is connected to the lubrication oil passage 61 branching from the upstream side of the check valve 60 that sets the normal lubrication oil pressure.
2 are connected in series, and an electromagnetic on-off valve 63 and a check valve 64 are installed in this oil passage 62. When the solenoid 65 is energized, the electromagnetic on-off valve G3 connects the oil passage 39c to the lubricating oil passage 61 via the bypass oil passage 62. A disconnection signal is input. That is, signals from the ignition pulse 69, accelerator switch 66, and vehicle speed switch 67 corresponding to the engine speed are input to the control circuit 68.
In the control system that controls the clutch current of the coil 8 of 118J, t'? The circuit is configured to energize the solenoid 65 when the clutch current is cut off during idling immediately before +1.

Further, the line pressure regulated by the pressure regulating valve 43 near the maximum speed ratio angle is, for example, 30 kg, -'cm2, and the normal lubricating oil pressure in the check valve 60 is, for example, 2 to 3 k (1
/Cm2 Guaru. Therefore, do you moisten the line pressure when idling? If the lithium oil is lowered to 1 mo, there is a risk of a delay in the line pressure rising during a sudden start, so in order to avoid this, the check valve 64 is used to set the line pressure to a level higher than the lubricating oil pressure, for example 10 kg/cm2. It's sea urchin.

With this configuration, during idling, line pressure discharged from the oil pump 31 is introduced into the sub-pulley servo chamber 281), while oil is drained from the main pulley servo chamber 27b by the speed change control valve 44. As a result, the drive belt 26 is wound most deeply on the main pulley 24 side, and the lower gear ratio with the largest gear ratio is moved by 1q. On the other hand, at this time, the load of the spring 55 is increased by the feedback link 5G in the T[)] regulating valve 43, so that the land 54a of the spool 54 is
is closed to increase the line pressure in oil passages 40.39c and 39b.

By the way, such an idle link state is detected by the clutch current of the coil 8 being cut in the control system of the electromagnetic powder clutch 1, and at this time, the electromagnetic on-off valve 63 is opened by energization of the solenoid 65, and the line pressure oil is opened. The oil passage 39c communicates with the hydraulic oil passage G1 via the bypass oil passage 62, and the oil pressure of these oil passages 39c and 391) is connected to the check valve 64.
Therefore, the oil pressure is set to a higher value than the normal oil pressure. In this way, the line pressure is lowered as shown by the broken line in Fig. 3 regardless of the pressure adjustment of the pressure regulating valve 43, and the lubricating oil passage 61 is brought into communication with each other, regardless of the decrease in the mail pump discharge pressure. There is sufficient lubrication of 1η.

Next, at the start of traveling, the switching section 3 of the continuously variable transmission I/2 is set to the forward or reverse state, and when the accelerator pedal is depressed,
The electromagnetic powder type clutch 1 is connected and power can be transmitted by supplying clutch current.

Then, the electromagnetic quantity opening valve 63 turns the solenoid 65 into a de-energized state.
, sr'! The oil passage 39c for the J/C line pressure is the oil passage 6 for lubrication.
1 to IJ pHl, and as a result, the in pressure immediately returns to the high value set by the pressure regulating valve 43, and the pressure force necessary for transmission of maximum torque is exerted.

From then on, the line pressure is regulated by the pressure regulating valve 43 as in the conventional case, and the line pressure is supplied to the main boulevard chamber 27b by the speed change control valve 46, thereby performing continuously variable speed control by converting the pulley ratio.

The above explanation is for the case where the electromagnetic clutch is disengaged, but the same applies when the shift lever is set to the neutral position with the electromagnetic clutch connected. The electromagnetic on-off valve 63 may be operated directly by the switch IO operated by the switch IO.

As is clear from the above explanation, according to the present invention, the electromagnetic clutch is disengaged in the "electromagnetic clutch" continuously variable transmission.
The discharge line pressure of the oil pump 37 is set low at the idling time, reducing the pump drive load, which reduces the load on the engine and stabilizes idling, making it easier for signal attendants, etc. to idle. Improves fuel efficiency in frequent driving patterns. In addition, the line pressure circuit during idling is connected to the lubrication circuit, so that despite the drop in the mail pump discharge pressure, the predetermined 1L pressure is maintained.
ffl slippage is ensured, and the line pressure in this case is set higher than normal lubrication oil pressure, so t15 is
A delay in the rise of the G-pulling line pressure can be avoided. Furthermore, since the line pressure is lowered by utilizing the disconnection signal of the electromagnetic clutch, there is no need to detect the idle link state, resulting in a simple structure and good operability.

[Brief explanation of the drawing]

Fig. 1 is a skeleton diagram showing an example of a continuously variable transmission to which the present invention is applied, Fig. 2 is a dimensional circuit diagram of an embodiment of a hydraulic control device according to the present invention, and Fig. 3 is a characteristic diagram. . 1... Electromagnetic powder clutch, 2... Continuously variable transmission, 3...
...Switching section, 4...Continuously variable transmission section, 5...Final reduction section,
6... Hydraulic control unit, 7... Crankshaft, 8... Coil, 9... Drive member, 10... Input shaft, 1
1... Driven member, 17... Main shaft, 22...
Switching clutch, 23... subshaft, 24... main pulley,
2b--auxiliary pulley, 26... drive bell 1-127.
28... Hydraulic servo device, 30... Output shaft, 37...
...Hydraulic pump, 38...Hydraulic control circuit, 39c...
・Line pressure oil path, 43...Pressure horn adjustment valve, 44...
・Speed control valve, 52...Drain oil path, 61...Lubrication oil path, C2...Oil path of bypass oil path, 63...
Electric fi & on/off valve, 64...check valve.

Claims (1)

[Claims] The discharge oil pressure of the oil pump, which is directly driven by the engine, is regulated by a pressure regulating valve, and the regulated line is constantly supplied to one of the pair of pulleys around which the drive belt is wound, thereby controlling the speed change. A hydraulic control device that uses a valve to supply oil to the other force of the pair of pulleys to achieve continuously variable speed is connected to the line pressure circuit on the outlet side of the oil pump and the lubricating circuit on the drain side. A bypass circuit is installed in between, and in the bypass circuit there is an on-off valve that is only heard when the engine and transmission are disconnected, and a dial valve that sets the line pressure higher than the lubricating oil pressure. Hydraulic control system for continuously variable transmission with electromagnetic clutch characterized by -n0