JP2890708B2 - Transmission shift control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for a transmission, and more particularly to a responsiveness on a side where a clutch pressure is reduced even when an oil viscosity is high at a low temperature. The present invention relates to a shift control device for a transmission capable of improving clutch disengagement and effectively using drain oil at high temperatures to avoid shortage of lubricating oil.

2. Description of the Related Art In a vehicle such as an automobile, a transmission is provided in order to appropriately extract power generated by an internal combustion engine according to a running state. The transmission includes a manual transmission in which the driver manually converts the power of the internal combustion engine to a required gear ratio according to the traveling state and takes out the power of the internal combustion engine automatically and at a required gear ratio according to the traveling state. Automatically converting and taking out steplessly,
That is, there is a continuously variable transmission and the like.

This continuously variable transmission is disclosed, for example, in Japanese Patent Application Laid-Open No. 63-1840. This publication discloses a rotation control device that transmits the power of an internal combustion engine to wheels via an electromagnetic clutch, a continuously variable transmission, an auxiliary transmission, and a differential device, and establishes a gear of the auxiliary transmission. It is provided to quickly eliminate the interference between the sleeve and the gear.

A shift control method for a continuously variable transmission is disclosed, for example, in Japanese Patent Application Laid-Open No. 62-196443. According to this publication, the sleeve of the synchronous meshing device is set to a position indicating the establishment of the gear position of the stepped transmission within a predetermined time after the shift lever is operated from the non-travel position to the travel position. When not retiring, a predetermined amount of torque is transmitted for a short time through the automatic clutch,
A relative rotational force is applied between the synchronous ring of the synchronous meshing device and the output gear of the stepped transmission, thereby enabling the relative rotation of the synchronous ring and the output gear that could not be relatively rotated with each other due to biting or the like. Things.

FIG. 7 shows a hydraulic control circuit of a shift control device for such a continuously variable transmission. That is, in FIG. 7, the continuously variable transmission 202 includes a primary sheave 206, a secondary sheave 208, and a clutch 210 that are driven by the hydraulic pressure of the hydraulic control circuit 204.

The oil pump 212 of the hydraulic control circuit 204 is connected to a line pressure passage.
Oil is supplied to 214 to generate a line pressure, and this line pressure acts on the secondary sheave 208.

A first line pressure control valve 216, a second line pressure control valve 218, a ratio pressure control valve 220, a clutch pressure control valve 222, and a manual shift valve 224 are connected to the line passage 214.

The ratio pressure control valve 220 communicates with the primary sheave 206 through the ratio pressure passage 226 to apply a ratio pressure to the primary sheave 206, and also controls the cooling control valve 228.
The ratio pressure is also applied.

The clutch pressure control valve 222 causes the clutch pressure to act on the clutch 210 and the cooling control valve 228.

The cooling control valve 228 supplies cooling oil from the cooling oil passage 30 to the clutch 210.

The clutch pressure control valve 222 is operated by a clutch solenoid 232, and communicates with a lubricating oil passage 236 that communicates with the lube pressure passage 234. A lube regulator valve 238 is provided in the lube pressure passage 234.

In order to efficiently use the oil supplied from the oil pump 212, the hydraulic control circuit 204 in FIG. 7 controls drain oil generated during hydraulic control in the second line pressure control valve 218 and the clutch pressure control valve 222. This is a so-called fixed hydraulic control circuit that leads to a lubricating oil system oil passage.

[Problems to be Solved by the Invention] By the way, in the hydraulic control circuit of the conventional shift control device, when the drain oil at the time of adjusting the clutch pressure is led to the lubricating oil passage, the lubricating oil is supplied even in the lubricating oil passage. A pressure for discharging is required. The pressure adjustment is performed by the rubble regulator valve, and the relationship between the clutch pressure and the duty of the clutch solenoid at this time is shown in FIG.

Then, even when the duty of the clutch solenoid is 100%, the pressure of the lubricating oil is obtained. For this reason, especially when the viscosity of the lubricating oil at a low temperature is high, as shown in FIG. 9, when the controllability (response) of the clutch pressure decreasing side (disengagement side of the clutch) becomes poor (slow). (Caused by poor clutch disengagement), there is a disadvantage that the engine speed is suddenly reduced and engine stall or the like occurs.

[Object of the Invention] Accordingly, an object of the present invention is to provide an on-off valve mechanism that operates in a lubricating oil passage and a clutch pressure adjustment drain oil passage that are operated in an oil temperature state in order to eliminate the above-mentioned disadvantages. When the oil viscosity is high at low temperatures, the response to the low side of the clutch pressure is accelerated, the clutch is disengaged satisfactorily to prevent engine stall, etc. At times,
A shift control device for a transmission that allows drain oil to flow into the lubricating oil passage and to be used effectively to prevent shortage of lubricating oil, to provide proper lubrication, and to reduce the size of the oil pump. To be realized.

Means for Solving the Problems To achieve this object, the present invention relates to a shift control device for a transmission having a clutch pressure control valve for controlling a clutch pressure applied to a clutch. A lubricating oil passage and a clutch pressure adjusting drain oil passage are provided in communication with each other. The lubricating oil passage is closed when the oil in the lubricating oil passage is lower than a set temperature, and the lubricating oil is closed when the oil is higher than a set temperature. A first opening / closing valve mechanism is provided in the middle of the lubricating oil passage to open a passage to allow drain oil to flow out to increase the responsiveness of the clutch pressure to a low side, and to adjust the clutch pressure when the oil is lower than a set temperature. A drain oil passage is opened to open to the atmosphere, and the clutch pressure adjustment drain oil passage is closed when the oil temperature is equal to or higher than a set temperature. A second opening / closing valve mechanism for allowing the drain oil to flow into the lubricating oil passage is provided by the clutch. The pressure adjusting drain oil passage is provided in the middle.

According to the configuration of the present invention, at the time of low temperature, the first on-off valve mechanism closes the lubricating oil passage and the second on-off valve mechanism opens the clutch pressure adjusting drain oil passage to the atmosphere. The responsiveness on the side where the oil flows to the outside to lower the clutch pressure becomes faster, the clutch disengagement becomes better, and the engine speed does not decrease so much that the occurrence of engine stall or the like can be prevented.

Further, at high temperatures, the first on-off valve mechanism opens the lubricating oil passage and the second on-off valve mechanism closes the clutch pressure adjusting drain oil passage, so that the drain oil flows into the lubricating oil passage. The lubrication oil can be used effectively, the amount of the lubricating oil does not become insufficient, the lubrication can be reliably performed, and the size of the oil pump can be reduced.

Embodiment An embodiment of the present invention will be described below in detail and specifically with reference to the drawings.

1 to 6 show an embodiment of the present invention.
In the figure, reference numeral 2 denotes a continuously variable transmission of a vehicle, and reference numeral 4 denotes a hydraulic control circuit of a shift control device. The continuously variable transmission 2 converts the power of an internal combustion engine (not shown) as required by continuously changing the gear ratio, and takes out the power. It has a secondary sheave 8 and a clutch 10.

The hydraulic control circuit 4 is provided with an oil pump 12. The oil pump 12 sucks oil in an oil pan (not shown) and sends the oil to a line pressure passage 14 to apply a line pressure to the secondary sheave 8.

An oil strainer 16 for filtering oil is provided between the oil pan and the oil pump 12.

A first line pressure control valve 20 is connected to the line pressure passage 14 via a first oil furnace 8, a second line pressure control valve 24 is connected via a second oil passage 22, and a third oil passage The ratio pressure control valve 28 is communicated via 26, the clutch pressure control valve 32 is communicated via a fourth oil passage 30, the manual shift valve 36 is communicated via a fifth oil passage 34, and the sixth oil passage A solenoid regulator valve 40 is connected via 38 and a relief valve 44 is connected via a seventh oil passage 42.

The first line pressure control valve 20 and the second line pressure control valve 24 are connected by an eighth oil passage 46.

The first line pressure control valve 20 has a line solenoid 48
The ninth oil passage 50 provided with is connected.

The ratio pressure control valve 28 has a ratio solenoid.
A tenth oil passage 54 provided with 52 is connected.

The ninth oil passage 50 and the tenth oil passage 54 are connected at a connection portion 56.

The ratio pressure control valve 28 communicates with the primary sheave 6 via a ratio pressure passage 58.

In the middle of the ratio pressure passage 58, an eleventh oil passage 62 communicating with the cooling control valve 60 is connected.

An oil cooler 66 is connected to the cooling control valve 60 via a twelfth oil passage 64, and the clutch pressure control valve 32 is connected via a thirteenth passage 68 where a clutch pressure is applied. The clutch 10 is communicated via the clutch 10. In the middle of the thirteenth passage 68, the manual shift valve
A fourteenth oil passage 72 communicating with 36 is connected.

A clutch solenoid 76 is connected to the clutch pressure control valve 32 via a fifteenth oil passage 74.

The clutch 10 is connected to a shift servo valve 80 via a sixteenth oil passage 78.

The shift servo valve 80 includes a servo cylinder 82, a servo piston 84 that moves in the servo cylinder 82, and a shift servo rod 86 fixed to the servo piston 84.
And a shift fork 88 fixed to the shift servo rod 86 to operate a forward / reverse switching mechanism (not shown).

The shift servo valve 80 and the manual shift valve 36
Are connected by a seventeenth oil passage 90 and an eighteenth oil passage 92 on which the clutch pressure acts.

A connection portion 56 between the ninth oil passage 50 and the tenth oil passage 54 is connected to a nineteenth oil passage 94 communicating with a clutch solenoid 76.

The nineteenth oil passage 94 is provided with a
20 oil passage 96 and the solenoid valve 40
21 oil passages 98-1 and 98-2, a 22nd oil passage 100 communicating with the first line pressure control valve 20, and a second oil passage 100 communicating with the clutch pressure control valve 32.
The three oil passages 102-1 and 102-2 are in communication.

Further, a lube pressure passage 104 is connected between the oil pump 12 and the second line pressure control valve 24. In the middle of the lube pressure passage 104, a lube pressure regulator valve 106 is provided.

The lube pressure passage 104 is connected to a twenty-fourth oil passage 108 for supplying oil for lubrication and cooling of each part,
The clutch pressure control valve 32 is communicated via 10 and the 26th oil passage 11
The cooling control valve 60 is connected via 2.

A lubricating oil passage communicating with the clutch pressure control valve 32
In the middle of the 25th oil passage 110, the first opening / closing that closes the 25th oil passage 110 when the oil in the 25th oil passage 110 is lower than the set temperature and opens the 25th oil passage 110 when the oil is higher than the set temperature. A valve mechanism 114 is provided. The first opening / closing valve mechanism 114 is made of, for example, a thermostat or a shape memory alloy.

Further, the clutch pressure control valve 32 is provided with a clutch pressure adjusting drain oil passage 116 that can be opened to the atmosphere. In the middle of the clutch pressure adjusting drain oil passage 116, when the oil is lower than the set temperature, the clutch pressure adjusting drain oil passage 116 is opened and opened to the atmosphere, and when the oil is higher than the set temperature, the clutch pressure adjusting drain oil passage 116 is closed. A second opening / closing valve mechanism 118 is provided. The second on-off valve mechanism 118 is made of, for example, a thermostat or a shape memory alloy, like the first on-off valve mechanism 114.

Further, the line solenoid 48, the ratio solenoid 5
2. The clutch solenoid 76 is controlled by the control means (ECU) (not shown) of the continuously variable transmission 2 by communicating with the control means (not shown).

 Next, the operation of this embodiment will be described.

At low temperatures, that is, when the oil in the hydraulic control circuit 4 is lower than the set temperature value and the viscosity of the oil is high, the first opening / closing valve mechanism 114 closes the twenty-fifth passage 110 and the second Since the on-off valve mechanism 118 opens the clutch pressure adjusting drain oil passage 116 to open to the atmosphere, the drain oil flows out and the clutch pressure changes as shown in FIG. The responsiveness of the clutch pressure in the disengagement side) is increased, whereby the disengagement of the clutch 10 is improved, and as shown in FIG. 6, the actual clutch pressure approaches the target clutch pressure, and the engine speed becomes extremely low. Therefore, occurrence of engine stall or the like can be prevented.

At this time, since the clutch pressure adjusting drain oil passage 116 is opened to the atmosphere, the amount of lubricating oil is reduced. However, since the temperature is low, there is no risk of seizure of each part and no inconvenience is caused.

On the other hand, when the temperature is high, that is, when the viscosity of the oil becomes lower than the set temperature, the first on-off valve
4 opens the 25th oil passage 110 and the second on-off valve mechanism 118
Closes the clutch pressure adjusting drain oil passage 116,
As shown in the figure, the clutch pressure changes to a high level, and drain oil flows into the 25th oil passage 110, which is a lubricating oil passage.
The amount of oil supplied from the oil pump can be used effectively, the amount of lubricating oil does not become insufficient, and the size of the oil pump 12 can be reduced.

Further, since a thermostat or a shape memory alloy is used as the first and second on-off valve mechanisms 114 and 118, the first and second on-off valve mechanisms 114 and 116 have a simple structure, are easy to install, and are inexpensive. It can be.

[Effects of the Invention] As is apparent from the detailed description above, according to the present invention, the lubricating oil passage and the clutch pressure adjusting drain oil passage are provided in communication with the clutch pressure control valve, and the oil in the lubricating oil passage is provided. When the oil temperature is lower than the set temperature, the lubricating oil passage is closed, and when the oil temperature is equal to or higher than the set temperature, the lubricating oil passage is opened to drain the drain oil to the outside, thereby increasing the responsiveness of the clutch pressure to a low side.
An on-off valve mechanism is provided in the middle of the lubricating oil passage, and when the oil is lower than the set temperature, the clutch pressure adjusting drain oil passage is opened and opened to the atmosphere, and when the oil is higher than the set temperature, the clutch pressure adjusting drain oil passage is closed and the drain is closed. By providing the second opening / closing valve mechanism in the middle of the clutch pressure adjusting drain oil passage for allowing oil to flow into the lubricating oil passage, the response to the clutch pressure on the low side is quick even when the viscosity of the oil at high temperatures is high. As a result, the clutch can be disengaged satisfactorily to prevent engine stall, etc., and the amount of drain oil can be used effectively at high temperatures. In addition, the size of the oil pump can be reduced.

[Brief description of the drawings]

1 to 6 show an embodiment of the present invention, FIG. 1 is a hydraulic control circuit diagram of a shift control device, FIG. 2 is an explanatory diagram showing an open / close state of first and second on / off valve mechanisms at a low temperature, FIG. 3 is an explanatory diagram showing the opening and closing states of the first and second on-off valve mechanisms at high temperatures, FIG. 4 is a diagram showing the relationship between the duty of the clutch solenoid and the clutch pressure at low temperatures, and FIG. FIG. 6 is a time chart showing the relationship between the duty of the clutch solenoid and the clutch pressure at the time, and FIG. 6 is a time chart of the clutch pressure and the engine speed. 7 to 9 show a conventional shift control device, FIG. 7 is a hydraulic control circuit diagram, FIG. 8 is a diagram showing a relationship between duty of a clutch solenoid and clutch pressure, and FIG. 9 is a diagram showing clutch pressure and engine pressure. It is a time chart with rotation speed. In the figure, 2 is a continuously variable transmission, 4 is a hydraulic control circuit, 10
Is a clutch, 14 is a line pressure passage, 28 is a ratio pressure control valve,
32 is a clutch pressure control valve, 58 is a ratio pressure passage, 68 is a clutch pressure passage, 110 is a 25th oil passage which is a lubricating oil passage, and 114 is a first oil passage.
On-off valve mechanism, 116 is a clutch pressure adjusting drain oil passage, and 1
Reference numeral 18 denotes a second on-off valve mechanism.

Claims (1)

(57) [Claims] In a shift control device for a transmission having a clutch pressure control valve for controlling a clutch pressure applied to a clutch, a lubricating oil passage and a clutch pressure adjusting drain oil passage are connected to the clutch pressure control valve. When the oil in the lubricating oil passage is below the set temperature, the lubricating oil passage is closed, and when the oil is above the set temperature, the lubricating oil passage is opened to drain the drain oil to the outside to reduce the clutch pressure. A first opening / closing valve mechanism for increasing the response to the low side is provided in the middle of the lubricating oil passage. When the oil is lower than the set temperature, the clutch pressure adjusting drain oil passage is opened to open to the atmosphere and the oil is at or above the set temperature. A transmission, wherein a second opening / closing valve mechanism for closing the clutch pressure adjusting drain oil passage and allowing the drain oil to flow into the lubricating oil passage is provided in the middle of the clutch pressure adjusting drain oil passage. Shift control device.