JPH1182655A - Pulley pressure supply device for belt type continuously variable transmission for vehicles - Google Patents

Abstract

(57) Abstract: A pulley is supplied to a cylinder chamber of a drive and a driven pulley even when a vehicle is towed with an engine stopped, thereby preventing the belt from rotating without being properly held between the two pulleys. When a vehicle is being towed with the engine stopped, oil discharged from a second hydraulic pump (8) driven by the rotational driving force of a power transmission mechanism between a driven pulley (25) and wheels is supplied in a solenoid type. Drive and driven pulley cylinder chambers 22, 26 via control valve 71
Therefore, both pulleys 21 and 25 maintain an appropriate pulley thrust pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulley pressure supply device for a vehicle belt-type continuously variable transmission having a belt-type transmission mechanism in which a belt is wound between a pair of pulleys having variable pulley widths.

[0002]

2. Description of the Related Art A belt-type speed change mechanism composed of a pair of pulleys having variable pulley widths and a belt wound between the pulleys is provided. It is well known that a belt-type continuously variable transmission that performs a continuously variable transmission by changing the winding diameter of the belt by appropriately changing the belt is used for vehicles and the like. The pair of pulleys is composed of a drive pulley and a driven pulley. Each pulley is composed of a fixed pulley half fixed to the pulley shaft and a movable pulley half movable in the axial direction of the pulley shaft.

[0003] Adjustment of the pulley width of both pulleys, that is, adjustment of the amount of movement of the movable pulley half in the axial direction, is appropriately performed in a cylinder chamber formed between the movable pulley half and the cylinder wall of the fixed pulley half. This is performed by supplying a predetermined pulley thrust pressure. The hydraulic pump for supplying the hydraulic pressure is constantly driven by a gear disposed on a shaft directly connected to the engine.

[0004]

Here, in a power transmission path from a driven pulley to a tire axle, for example, as in a belt-type continuously variable transmission having a torque converter and thereby providing a starting clutch function, In the case of a transmission in which a clutch device is not provided, the driven pulley and the tire axle are mechanically connected and always operate in conjunction with each other. In a vehicle having such a transmission,
For example, when the vehicle is towed when the engine has failed, the rotation of the tire is transmitted to the belt via the tire axle and the driven pulley, and the belt rotates between the two pulleys. At this time, the engine is stopped, the hydraulic pump does not operate, and the pulley thrust pressure is not supplied to the cylinder chamber, so that the belt continues to rotate without being properly held between the two pulleys.

In order to obtain an appropriate pulley thrust pressure, it is conceivable to provide a spring or the like in the cylinder chamber.
In order to obtain the necessary and sufficient pulley thrust pressure with the spring, a spring with a large set load is required.
It is quite difficult in terms of space.

The present invention has been made in view of such a problem, and a pulley thrust pressure is supplied to a cylinder chamber even when a vehicle is towed while the engine is stopped, so that the belt is not properly held between the two pulleys. An object of the present invention is to provide a pulley pressure supply device for a belt-type continuously variable transmission that can prevent rotation in a state.

[0007]

In order to achieve the above object, a pulley pressure supply device for a belt type continuously variable transmission according to the present invention changes a pulley width by a pulley pressure supplied to a drive side cylinder chamber. A belt-type continuously variable transmission mechanism comprising a drive pulley capable of being driven, a driven pulley capable of changing a pulley width by a pulley pressure supplied to a driven side cylinder chamber, and a belt wound between these pulleys, and a drive pulley , A drive source for supplying the driving force to the wheels, an output transmission means for transmitting the output of the driven pulley to the wheels, a first hydraulic pump driven by the drive source, and a second hydraulic pressure driven by the rotational driving force of the output transmission means When the pump and the drive source are driven, the pulley pressure is supplied to both cylinder chambers using the discharge oil from the first hydraulic pump, and when the drive source is stopped. Composed of a pulley pressure supply control means for supplying the pulley pressure to both cylinder chambers with the discharge oil from the second hydraulic pump. In addition, the pulley pressure supply control means,
When the drive source is driven, the oil path switching means is turned on to supply the pulley pressure to both cylinder chambers using the discharge oil from the first hydraulic pump, and the drive source is stopped. Sometimes, the oil passage switching means may be turned off and the pulley pressure may be supplied to both cylinder chambers using the discharge oil from the second hydraulic pump.

According to the above construction, the discharge oil from the second hydraulic pump driven by the rotational driving force of the output transmission means is supplied to the two cylinder chambers as the pulley pressure by the pulley pressure supply control means when the vehicle is towed. The belt can be prevented from rotating without being properly held between the pulleys. Further, if the pulley pressure supply control means has a solenoid type oil passage switching means that is turned on / off by energization from a generator driven by the engine, the above control is automatically performed in response to driving or stopping the engine. It is definitely done because it is done.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. 3 and 4 show the configuration of a belt-type continuously variable transmission having a pulley pressure supply device according to the present invention. The belt-type continuously variable transmission is configured to have a belt-type continuously variable transmission mechanism in a housing 1, and the housing 1 has a joint surface 2 with an engine flywheel housing at a left end, and the joint surface 2 A transmission is mounted on the engine to be joined to the flywheel. At this time, the first shaft S1 is located coaxially with the engine output shaft Es. In the following description, each rotation center axis of the transmission, such as a rotating shaft and a gear, is referred to as a first axis S.
Although shown as first to fourth axes S4, this means the central axis.

In this belt type continuously variable transmission, a torque converter 5 is mounted on a first shaft S1 in a housing 1.
(Comprising an impeller 5a, a turbine 5b and a stator 5c) and a forward / reverse switching mechanism 4 in parallel. The engine output shaft Es is connected to the impeller 5a of the torque converter 5, and the turbine 5b of the torque converter 5 is connected to the turbine shaft 6 (which is also the input shaft of the forward / reverse switching mechanism 4). The torque converter 5 has a lock-up clutch 5d that can directly connect the engine output shaft Es and the turbine 5b. The forward / reverse switching mechanism 4 has a double pinion type planetary gear, and includes input / output members (the turbine shaft 6 and the first shaft 2).
3) is provided with a forward clutch 11 that can be directly connected and a reverse brake 12 that can fix and hold the ring gear. By selectively operating these forward clutch 11 and reverse brake 12, the first shaft 23
Can be rotated forward or reverse.

The first hydraulic pump 3 is mounted on the torque converter case 13 and is driven via a chain 7 by a gear disposed on an end of the torque converter 5 and provided on a hub connected to the impeller 5a. . The first hydraulic pump 3 sucks oil through a strainer built in an oil pan below the transmission. The suction oil reaches the first hydraulic pump 3 via a joint pipe and the like via a suction oil passage formed in a lower portion of a transmission case and in a valve body. Suction by the first hydraulic pump 3
The discharged oil is used for a control oil pressure required for shifting, a torque converter system, lubrication, and cooling via a torque converter case oil passage and a hydraulic control circuit.

The first shaft 23 has a fixed pulley half 21a formed integrally therewith, and a movable pulley half 21b opposed thereto and disposed movably in the axial direction on the first shaft 23. Is provided. On the side of the movable pulley half 21b, a drive cylinder chamber 22 is formed surrounded by a cylinder wall 12a connected to the fixed pulley half 21a. That is, the movable pulley half 21b can be moved in the axial direction by controlling the pulley thrust pressure (corresponding to the pulley pressure in the claims).

A second shaft 27 is rotatably provided on a second shaft S2 extending parallel to the first shaft S1 at a predetermined distance from the first shaft S1, and a fixed pulley integrally formed with the second shaft 27. The driven pulley 25 is composed of the half 25a and the movable pulley half 25b that is opposed to the half 25a and that is arranged movably in the axial direction on the second shaft 27. On the side of the movable pulley half 25b, a driven cylinder chamber 26 is formed surrounded by a cylinder wall connected to the fixed pulley half 25a, and hydraulic pressure supplied into the driven cylinder chamber 26, that is, By controlling the pulley thrust pressure, the movable pulley half 25b can be moved in the axial direction.

Drive pulley 21 and driven pulley 25
A metal V-belt 24 is wound around and a belt-type continuously variable transmission mechanism is formed. The rotation of the drive pulley 21 is transmitted to the driven pulley 25 via the V-belt 24. At this time, the movable pulley 2 of the two pulleys 21 and 25
By moving the pulleys 1a and 25a to adjust the pulley width, the winding radius of the belt between the pulleys 21 and 25 can be arbitrarily adjusted, and the reduction ratio between the pulleys 21 and 25 is adjusted steplessly. can do.

The first gear 1 is located on the left side of the driven pulley 25.
4 is provided in connection with the second shaft 27. Second
A third shaft 28 is rotatably provided on a third shaft S3 extending parallel to the predetermined distance from the shaft S2, and the second gear 15 and the third gear 16 are integrally formed on the third shaft 28. I have. The first gear 14 meshes with the second gear 15.
A differential mechanism 18 is provided on a fourth shaft S4 extending parallel to the third shaft S3 at a predetermined distance from the third shaft S3. A fourth gear 17 coupled to the differential mechanism 18 is connected to a third gear 16 Meshes with in this way,
A power transmission gear train is constituted by the first to fourth gears 14, 15, 16, 17 and rotation of the driven pulley 25 is performed via the power transmission gear train by the differential mechanism 1.
8 is transmitted.

On the housing 1 on the left side of the third shaft 28, a second hydraulic pump 8 is bolted, and the rotating shaft of the second hydraulic pump 8 is connected to the third shaft 28.
The second hydraulic pump 8 is driven by receiving the rotational driving force of the third shaft 28.

The left and right axle shafts 29 and 30 are connected to the differential mechanism 18, and the power transmitted to the differential mechanism 18 is divided here and the left and right wheels (shown in the figure) are passed through the left and right axle shafts 29 and 30. (The power transmission mechanism from the driven pulley 25 to the axle shafts 29 and 30 via the power transmission gear train after the driven pulley 25 corresponds to an output transmission means in the claims).

Next, a hydraulic control device used in the continuously variable transmission having the above-described configuration will be described with reference to hydraulic circuit diagrams shown in FIGS. In this circuit diagram, circled numbers are connected to each other, and an x mark means that the portion is connected to the drain.

The first driven by the rotational force of the engine
The discharge oil of the hydraulic pump 3 is supplied to the high-pressure regulator valve 41 via the oil passage 32 and to the reducing valve 58 via the oil passage 36. The reducing valve 58 generates a line pressure PMOD having a substantially constant hydraulic pressure, and supplies the hydraulic oil having the line pressure to the oil passages 31, 37a, 37b, and 37c.

The oil passage 37a is provided with a high / low pressure control valve 4
Connect to 5. The high / low pressure control valve 45 has a linear solenoid 45a, the current supplied to the linear solenoid 45a is controlled, and the pressing force acting on the spool 45b from the linear solenoid 45a is controlled to supply the oil from the oil passage 37a. The line pressure PMOD is adjusted, and the control back pressure PHLC corresponding to this pressing force is adjusted to the oil passage 35.
a, 35b. This control back pressure PHLC is
a, the right end oil chamber 43 of the low pressure regulator valve 43
b, and acts to press the spool 43a to the left. The control back pressure PHLC is supplied to the right end oil chamber 47b and the first intermediate oil chamber 47c of the high pressure control valve 47 via the oil passage 35b,
a so as to press a leftward and rightward.

The high pressure regulator valve 41 regulates the operating oil pressure supplied from the first hydraulic pump 3 via the oil passage 32, and supplies the high pressure control pressure PH to the oil passages 33a and 33b. This high pressure control pressure PH is applied to the oil passage 33a.
And supplied to the low-pressure regulator valve 43 via an oil passage 33b. Further, the high pressure control pressure PH is also supplied to an oil passage 33c connected to the left end oil chamber 47d of the high pressure control valve 47.

The second intermediate oil chamber 47e of the high pressure control valve 47 has an oil passage 37c to which the line pressure PMOD is supplied.
Is connected. The oil passage 37c has an orifice 56 and is connected to a solenoid valve 55 downstream of the orifice 56.
, The supply of the line pressure PMOD to the second intermediate oil chamber 47e is controlled. In the high-pressure control valve 47, the position of the spool 47a is controlled by the control back pressure PHLC supplied to the right end oil chamber 47b and the first intermediate oil chamber 47c and the line pressure PMOD supplied to the second intermediate oil chamber 47e. The hydraulic pressure generated by adjusting the high-pressure control pressure PH supplied from 33c is supplied as back pressure to the right end oil chamber 41b of the high-pressure regulator valve 41 via the oil passage 33d.

The low pressure regulator valve 43 receives the control back pressure PHLC, regulates the high pressure control pressure PH supplied from the oil passage 33b, and supplies the low pressure control pressure PL to the oil passage 34. This low pressure control pressure PL is supplied to the shift valve 53 via oil passages 34 a and 34 b branched from the oil passage 34.

The shift control valve 51 has a linear solenoid 51a, and a current supplied to the linear solenoid 51a is controlled. By controlling a pressing force acting on the spool 51b from the linear solenoid 51a, the shift control valve 51 is connected to the oil passage 37b. The supplied line pressure PMOD is adjusted, and a shift control pressure PSV corresponding to the pressing force is supplied to the oil passage 38. This shift control pressure PSV is supplied to the left end oil chamber 53c of the shift valve 53, and acts to press the spool 53a rightward.

The shift valve 53 controls the supply of the high and low pressure control pressures PH and PL to the drive-side and driven-side cylinder chambers 22 and 26 via the oil passages 39a and 39b as appropriate according to the position of the spool 53a. Do. Here, the spool 53a is pushed leftward by the spring 53b, and is pushed rightward by receiving the shift control pressure PSV supplied to the left end oil chamber 53c. Therefore, the position of the spool 53a can be controlled by controlling the shift control pressure PSV. As a result, the hydraulic pressure (pulley thrust pressure) in the drive-side and driven-side cylinder chambers 22, 26 is controlled to control the belt mechanism. The speed reduction ratio at 10 can be controlled steplessly.

On the other hand, the line pressure PMOD supplied from the reducing valve 58 to the oil passage 31 is supplied to a manual valve 61. The manual valve 61 is connected to a shift lever of a driver's seat (not shown) via a control cable, and is operated by a manual operation of the driver. P, R, N, D, S, L
There are six positions, and the spool 61a of the manual valve 61 is moved to the corresponding position shown in the figure according to the operation position. The drawing shows a state in which the spool 61a is at the N (neutral) position. The first oil chamber 61b of the manual valve 61 is directly connected to the forward clutch 11 via the oil path 64, and the second oil chamber 61c is connected to the reverse brake control valve 65 via the oil path 63. An oil passage 67 connected to the reverse brake 12 is connected to the reverse brake control valve 65.

The manual valve 61 includes a spool 6
When 1a is at the P, N position, the oil passage 63 and the oil passage 64
To the drain together. For this reason, the forward clutch 11
Neither the reverse brake 12 nor the engagement operation is performed. or,
When the spool 61a is at the D, S, L position, the oil passage 6
3 is connected to the drain, and the line pressure PMOD supplied from the oil passage 31 is supplied to the oil passage 64. Therefore, the reverse brake 12 is released, and the forward clutch 11 is engaged. Further, when the spool 61a is at the R position, the oil passage 64 is connected to the drain, and the line pressure PMOD supplied from the oil passage 31 is supplied to the oil passage 63. Therefore, the forward clutch 11 is released, and the reverse brake 12 is controlled to be engaged and released by the operation of a reverse brake control valve 65 described below.

The reverse brake control valve 65 has a linear solenoid 65a, and the pressing force of the linear solenoid 65a acts on the spool 66. For this reason, the line pressure PMOD supplied through the oil passage 63 is reduced by the linear solenoid 65a.
The reverse brake control pressure Prv is adjusted in accordance with the current flowing through the vehicle.
Is generated, and the reverse brake control pressure Prv is applied to the oil passage 67.
Is supplied to the reverse brake 27. As can be seen from this, the engagement of the reverse brake 27 can be controlled by the reverse brake control valve 65, that is, by controlling the current supplied to the linear solenoid 65a.

In the control device configured as described above,
If the forward clutch 11 or the reverse brake 12 is engaged, the vehicle can run, and the control hydraulic pressure PSV
Is controlled to control the position of the spool 53a of the shift valve 53, the drive-side and driven-side cylinder chambers 2 are controlled.
The shift control can be performed by controlling the pulley thrust pressures in the pulleys 2 and 26.

The oil discharged from the second hydraulic pump 8 driven by the rotation of the third shaft 28 is supplied to a solenoid-type directional control valve 71 through an oil passage 72.
The solenoid-type directional control valve 71 supplies the discharge oil from the second hydraulic pump 8 to an oil passage 75 that joins with the oil passage 32 when energization is on. On the other hand, when the power is turned off, the discharge oil from the second hydraulic pump 8 is supplied to the shift valve 53 via the oil passage 73 joining the oil passage 33a and the oil passage 74 joining the oil passage 34. The oil passage 72 is provided with a relief valve 76 that branches off from the oil passage 72a. When the oil pressure from the second hydraulic pump 8 is equal to or higher than the set pressure, the oil is relieved therefrom. A check valve is provided in each of the oil passages 73 and 74 and the oil passage 75 so that the discharge oil from the first hydraulic pump 3 does not flow toward the solenoid type directional control valve 71.

The hydraulic control device (corresponding to the pulley pressure supply control means in the claims) including the solenoid type directional control valve 71 drives the engine during normal running, that is, when the vehicle is running by driving the engine. Solenoid-operated directional control valve 71
Is supplied to the oil passage 7 and the oil discharged from the second hydraulic pump 8
5 joins the oil passage 32 to perform the auxiliary function of the first hydraulic pump 3. On the other hand, when the vehicle is towed, that is, when the engine is stopped and power is not supplied to the solenoid type directional control valve 71 and the tires are forcibly driven, the second
The discharge oil of the hydraulic pump 8 passes through the shift valve 53 and is converted into a pulley thrust pressure by the drive-side and driven-side cylinder chambers 2.
2, 26.

Since the pulley thrust pressure is supplied to the drive-side and driven-side cylinder chambers 22 and 26, the V-belt 24 rotates without being properly held between the pulleys 21 and 25 when the vehicle is towed. Can be prevented. or,
By using the solenoid type directional control valve 71, the second
Since the switching control of the oil passage from the hydraulic pump 8 is automatically performed in response to driving or stopping of the engine, it is ensured.

The drive and driven cylinder chambers 22,
The pulley thrust pressure 26 is set to the same pressure for simplification of the structure, but may be set to be higher on the drive side than on the driven side. In this case, the belt diameter on the drive pulley 21 side becomes larger than the diameter on the driven pulley 25 side,
Therefore, the rotation speed of the drive pulley 21 is
Since the number of rotations is smaller than 5, the number of rotations is effective for protecting the planetary gear unit. Further, a configuration may be adopted in which the excess discharge oil relieved by the relief valve 76 provided in the oil passage 72a is supplied to the lubricating oil passage.

In the above-described embodiment, the oil discharged from the second hydraulic pump 8 is supplied to the oil passage 75 during normal running to play an auxiliary role for the first hydraulic pump 3. May be connected directly to the oil tank and drained.

Further, instead of the above configuration, the third shaft 2
A power intermittent switch that can manually perform power intermittent operation may be provided between the second hydraulic pump 8 and the second hydraulic pump 8. In this case, when the vehicle is towed, the power intermittent switch is manually operated to establish the power connection state, the second pump 8 is driven by the third shaft 28, and the discharge oil is supplied to the shift valve 53. On the other hand, when the vehicle travels normally, it is manually operated to set the power cutoff state so that the second pump 8 does not hinder the rotation of the third shaft 28. As a result, similarly to the configuration using the solenoid type directional control valve 71, the V-belt 24 pulls the two pulleys 21
Rotation in a state where it is not properly held between the five can be prevented.

[0036]

As described above, according to the pulley pressure supply device of the belt-type continuously variable transmission according to the present invention, the pulley pressure supply control means is driven by the rotational driving force of the output transmission means when the vehicle is towed. Since the discharge oil from the second hydraulic pump is supplied as pulley pressure to the drive-side and driven-side cylinder chambers, it is possible to prevent the belt from rotating without being properly held between the two pulleys.

Further, if the pulley pressure supply control means has a solenoid type oil passage switching means which is turned on / off by energization from a generator by driving the engine, the above control is performed when the engine is driven or stopped. It is sure because it is automatically made in response.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the overall configuration of a belt-type continuously variable transmission having a pulley pressure supply structure according to the present invention.

FIG. 2 is a skeleton diagram showing a power transmission path configuration in a belt-type continuously variable transmission having a pulley pressure supply structure of the present invention.

FIG. 3 is a hydraulic control circuit diagram of the pulley pressure supply structure of the present invention.

FIG. 4 is a hydraulic control circuit diagram of the pulley pressure supply structure of the present invention.

[Explanation of symbols]

 3 First hydraulic pump 8 Second hydraulic pump 21 Drive pulley 24 V belt 25 Driven pulley 71 Solenoid type directional control valve

Claims (2)

[Claims] 1. A drive pulley whose pulley width can be changed by a pulley pressure supplied to a drive-side cylinder chamber, a driven pulley whose pulley width can be changed by a pulley pressure supplied to a driven-side cylinder chamber, and between these two pulleys. A belt-type continuously variable transmission mechanism including a wound belt; a drive source for supplying a driving force to the drive pulley; output transmission means for transmitting an output of the driven pulley to wheels; and the drive source. A first hydraulic pump to be driven; a second hydraulic pump to be driven by the rotational driving force of the output transmission means; and a hydraulic pump that uses discharge oil from the first hydraulic pump when the drive source is being driven. A pulley pressure is supplied to the cylinder chambers, and when the driving source is stopped, the pump oil is discharged to the two cylinder chambers by using the discharge oil from the second hydraulic pump. Pulley pressure supply device for a vehicular belt-type continuously variable transmission, characterized by comprising a pulley pressure supply control means for supplying the pressure. 2. The pulley pressure supply control means includes a solenoid type oil path switching means. When the drive source is driven, the oil path switching means is turned on to discharge oil from the first hydraulic pump. To supply the pulley pressure to the two cylinder chambers, and when the drive source is stopped, the oil passage switching means is turned off, and the pulley pressure is supplied to the two cylinder chambers using the discharge oil from the second hydraulic pump. The pulley pressure supply device for a belt-type continuously variable transmission for a vehicle according to claim 1, wherein