JPS628659B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that enables switching of four types of hydraulic circuits by controlling the positions of three spools by opening and closing operations of two electromagnetic valves, and in particular, the present invention relates to a device that enables switching of four types of hydraulic circuits by controlling the positions of three spools by opening and closing operations of two solenoid valves. It is suitable as a shift control valve.

BACKGROUND OF THE INVENTION With the automation of various industrial equipment, hydraulic control devices are being used in addition to electrical and mechanical control devices as they have excellent reliability and durability. This hydraulic control device often incorporates a hydraulic switching valve that switches the hydraulic circuit. In this case, switching a large-flow hydraulic circuit using a solenoid valve requires a large-capacity solenoid, which is not only expensive and uneconomical but also disadvantageous from a space-saving perspective.
Conventionally, solenoid valves are used as pilot valves to operate large-capacity hydraulic switching valves, but in order to control multiple hydraulic switching valves, as many solenoid valves as there are hydraulic switching valves are used. This may cause problems in terms of cost and space.

For example, in recent years, the design policy for internal combustion engine vehicles has focused almost entirely on improving fuel efficiency, so hydraulic control devices for automatic transmissions are also required to be lighter and space-saving, and the number of gears has increased. It's being left out of nowhere. For this reason, it is necessary to incorporate a plurality of shift valves and at the same time use a number of solenoid valves corresponding to the number of shift valves, which complicates the structure and conflicts with the aim of reducing weight and saving space. It was closed.

In view of the fact that conventional hydraulic control equipment equipped with multiple large-capacity hydraulic switching valves has become larger and more expensive, the present invention is designed to be incorporated into automatic transmissions for automobiles that can provide four forward gear ratios. An object of the present invention is to provide a hydraulic distribution device in which three shift valves can be operated by two electromagnetic valves, and which can reduce the weight and size of hydraulic control equipment at low cost.

The configuration of the hydraulic distribution device of the present invention that achieves this object includes a first spool and a second spool that are slidably fitted into a hole formed in a valve body and that face each other, and two a third spool that has a land and is slidably fitted into the hole between the first spool and the second spool and is applied with a pressing force toward the first spool; An oil drain path and a hydraulic pressure supply path are connected in parallel to each other in the hole between the first spool and the second spool, and a hydraulic pressure supply path is connected in parallel to the hole between the oil drain path and the oil pressure supply path. three distribution control oil passages whose communication with the oil drainage passage or the oil pressure supply passage is switched depending on the position of the third spool; and pressure into the hole between the first spool and the third spool. a first solenoid valve that controls oil supply and discharge;
The second solenoid valve controls supply and discharge of pressure oil for pressing the first spool and the second spool toward the third spool.

Hereinafter, an embodiment in which the hydraulic distribution device according to the present invention is applied to a hydraulic control device for an automatic transmission of an automobile capable of obtaining four forward speed gear ratios will be described below. Fig. 1 shows a schematic system of the entire system and a schematic structure of the main parts. This will be explained in detail with reference to FIG. As is clear from Fig. 1, the basic structure of this hydraulic control device is well known, and the conventional power train can be used as is. Descriptions of components other than those of the invention have been simplified as much as possible to avoid redundancy.

The output of an engine (not shown) is transmitted via a torque converter 11 or a direct coupling clutch 12 having a predetermined slip ratio to a transmission gear train (not shown) capable of achieving four forward speeds and one reverse speed. The front clutch 13, rear clutch 14, 4-speed clutch 15, kickdown brake 16, and low reverse brake 17 incorporated in the transmission gear train are each friction engagement devices, and the hydraulic pressure for operating them is supplied from an oil pump 18. obtain. There is also a select lever on the driver's seat (not shown) and a select lever (described later).
D ₄ , D ₃ , 2, and L are selected according to the operation of the auxiliary switch and the driving state of the vehicle detected by various driving state detection devices.
Seventeen selective engagements are made and the various gears are automatically achieved. In this case, the selection patterns are P (parking), R (reverse), N (neutral), D ₄ (four forward automatic transmission), D ₃ (three forward automatic transmission), 2 (two forward automatic transmission), L (first speed fixed), and the select lever has four positions: P, R, N, and D. When the D position is selected and an auxiliary switch consisting of a changeover switch (not shown) is selected, the select lever is set to L. , 2, D ₃ , and D ₄ are selected.

The hydraulic control system shown in FIG. In order to operate each hydraulic piston (not shown) of the reverse brake 17 and 4-speed clutch 15, the hydraulic pressure supplied to each hydraulic chamber is controlled according to the operating state, and the pressure regulating valve 21, torque converter control valve 22, Direct coupling clutch control valve 23, pressure reducing valve 24, shift control valve 25, manual valve 26, 1st-2nd speed shift valve 27, 2nd-3rd speed, 4th-3rd speed shift valve 28,
An ND control valve 29, a 4-speed clutch control valve 30, a shift oil pressure adjustment valve 31, an NR control valve 32, and a rear clutch control valve 33 are connected to each other via oil passages. Further, two electromagnetic valves 35 and 36 of a type closed when energized, whose opening and closing are duty-controlled by a computer 34, are attached to the direct coupling clutch control valve 23 and the oil pressure regulating valve 31.
Two electromagnetic valves 37 and 38 of a non-energized closed type whose opening and closing are controlled via the shift control valve 25 are attached to the shift control valve 25.

The shift control valve 25 is controlled by a combination of opening and closing of two electromagnetic valves 37 and 38 to obtain each of four forward gears. A third spool 43 having lands 41 and 42 with different diameters is located between the first spool 39 and the second spool 40 that face each other. It is slidable. The reciprocating range of the first spool 39 and the second spool 40 is determined by stoppers 46 and 47 formed in the hole 45, and the third spool 43 has a pressure receiving area when hydraulic pressure acts between the lands 41 and 42. Due to the difference, it is always pressed toward the first spool 39 side.
In this case, the third spool 43 may be pressed toward the first spool 39 via a spring. Between the second spool 40 and the third spool 43 there is an oil drain passage 48, and a third distribution control oil passage 4 that communicates with the fourth speed clutch control valve 30 and the rear clutch control valve 33.
9. Second distribution control oil passage 50 communicating with 2nd speed - 3rd speed / 4th speed - 3rd speed shift valve 23 and 4th speed clutch control valve 30; 1st speed - 2nd speed shift valve 27 and 4th speed clutch control valve 30; A first distribution control oil passage 51 is formed in order to communicate with the manual valve 26, and between the two lands 41 and 42 of the third spool 43, a first distribution control oil passage 51 is formed which communicates with the manual valve 26 and from which hydraulic pressure is supplied. Hydraulic supply path 52
is formed so as to be in constant communication with the hole 45.
Further, a second hydraulic pressure supply path 53 branching from the first hydraulic pressure supply path 52 communicates with a hole 45 between the first spool 39 and the second spool 40, and an orifice 54 is formed in the middle. In addition, the first hydraulic supply path 5
The third hydraulic supply path 55 connected to the hole 45 is branched into two parts in the middle, each opening at both ends of the hole 45.
An orifice 56 is formed in the middle. The solenoid valve 37 is interposed between the port 57 of the second hydraulic supply path 53 and the orifice 54, and the solenoid valve 38 is interposed between the two ports 58 of the third hydraulic supply path 55 and the orifice 5.
It is interposed between 6 and 6.

Therefore, when the manual valve 26 is in position D and hydraulic pressure is supplied to the shift control valve 25 from the first hydraulic pressure supply path 52, the first gear is shifted by operating the solenoid valves 37 and 38 via the computer 34. -2nd speed shift valve 27, 2nd speed -3rd speed/4th speed -3rd speed shift valve 28, 4
Quick clutch control valve 30, rear clutch control valve 33
It becomes possible to control the operation of the That is, when the spools 59 and 60 of the two solenoid valves 37 and 38 move to the right in FIG. 2 against the spring force of the compression coil springs 61 and 62, respectively, the orifice 5
4 and 56, the pressure oil in the second hydraulic supply path 53 and the third hydraulic supply path 55 is first drained, but the lands 41 and 42 of the third spool 43 are drained by the pressure oil from the first hydraulic supply path 52. Third spool 4 due to pressure receiving area difference
3 moves to the right end as shown in the drawing while pushing the first spool 39, and the second spool 40 also moves to the left in the drawing by pressure oil from the first to third distribution control oil passages 51, 50, and 49. Therefore, the first to third distribution control oil passages 51 to 49 communicate with the drain oil passage 48, and the first hydraulic pressure supply passage 52 and the first to third distribution control oil passages 51 to 49 are cut off. The supply of hydraulic pressure to the first to third distribution control oil passages 51 to 49 is stopped. As a result, the rear clutch 14 and the low reverse brake 17 are activated to achieve the first gear. When only the spool 60 of the electromagnetic valve 38 is closed, the pressure oil from the manual valve 26 flows into the third hydraulic pressure supply path 55 via the first hydraulic pressure supply path 52, and the first spool 39 receives pressure oil from the lands 41 and 42. The second spool 40 moves together with the third spool 43 until it comes into contact with the stopper 46 against the pressure receiving area difference of , and at the same time the second spool 40 moves until it comes into contact with the stopper 47 . As a result, the small diameter land 42 of the third spool 43 moves between the first distribution control oil passage 51 and the second distribution control oil passage 0, and the first oil pressure supply passage 52 and the first distribution control oil passage 51 move. communicates with each other to operate the 1st-2nd speed shift valve 27, the rear clutch 14
and the kick-down brake 16 are activated to achieve the second gear. Furthermore, when the spool 59 of the solenoid valve 37 is also closed, the pressure oil from the manual valve 26 also flows into the second hydraulic supply path 53 and is sent between the first spool 39 and the third spool 43, but The diameter of the first spool 39 and the third spool 4
The third spool 43 moves until it comes into contact with the second spool 40 due to the difference in diameter from the third large diameter land 41. As a result, the small-diameter land 42 of the third spool 43 stops between the second distribution control oil passage 50 and the third distribution control oil passage 49, and the first oil pressure supply passage 52
and the first and second distribution control oil passages 51, 50 communicate with each other, and in addition to the 1st-2nd speed shift valve 27, the 2nd-3rd speed shift valve
Since the 4th speed-3rd speed shift valve 28 is also operated, the front clutch 13 and the rear clutch 14 are respectively activated to achieve the third speed. At this time, the 4th speed clutch 1 is controlled via the 4th speed clutch control valve 30.
5 is also supplied with pressure oil, and this 4-speed clutch 15 is also engaged, but since the gear transmission is in a directly connected state at 3rd speed or higher, there is no problem. Furthermore, when the spool 60 of the solenoid valve 38 is opened from this state, the oil is drained from the third hydraulic supply path 55 and the first spool 39 and the second spool 40 are moved to both ends of the hole 45 so as to separate from each other. As the second spool 40 moves, the third spool 43 also moves together with the second spool 40 due to the pressure oil from the second hydraulic supply path 53, and the small diameter land 42 is connected to the oil drain path 48 and the third spool 40. Since it stops between the distribution control oil passage 49 and the first oil pressure supply passage 52 and the first to third distribution control oil passages 51 to 49, all of them communicate with each other, and the first to second gear shift valves 27 and 2nd gear are connected to each other. 3rd/4th speed - 3rd speed shift valve 2
8. All the 4-speed clutch control valves 30 and rear clutch control valves 33 are operated, and the front clutch 1
3 and the rear clutch 14, and the 4th speed clutch 15 and the kickdown brake 1 are discharged.
6 works to achieve a 4th speed gear ratio. In this case, the relationship between each of the frictional engagement devices 13 to 17 and the transmission gear train is already well known, and in short, the present invention explains that the third spool 43 can select four stop positions using the two electromagnetic valves 37 and 38. Since it is sufficient if the transmission gear train and the frictional engagement devices 13 to 17
A description of the mechanical connection relationship with the above will be omitted.

In this embodiment, the first hydraulic pressure supply path 52 is opened between the two lands 41 and 42 of the third spool 43, but as shown in FIG. 3 which shows the structure of another embodiment of the present invention. , may be formed on the opposite side of the first to third distribution control oil passages 51, 50, 49 with respect to the oil drain passage 48. In this case, it is necessary to provide the third spool 43 with a land 63 that comes into contact with the second spool 40 so that the oil drain path 64 for excess oil does not communicate with the first hydraulic supply path 52, and the solenoid valve 3
7 and 38 are open type when not energized. Therefore, when only the solenoid valve 37 is excited, the first speed is achieved, when the solenoid valves 37 and 38 are excited, the second speed is achieved, and when only the solenoid valve 38 is excited, the third speed is achieved, and both the solenoid valves 37 and 38 are not excited. And the first ~
The third distribution control oil passages 51, 50, and 49 communicate with the first oil pressure supply passage 52 to achieve fourth speed. In addition,
In the figure, members having the same functions as those shown in FIG. 2 are designated by the same reference numerals. In this embodiment, the lands 41 and 42 of the third spool 43 have the same diameter, and when the solenoid valve 37 is de-energized, the orifice 5
4, the third spool 43 is pressed toward the first spool 39, but a preload may be applied to the first spool 39 by a spring in advance.

As described above, according to the hydraulic distribution device of the present invention, it is possible to control three hydraulic switching valves simultaneously by combining the opening and closing operations of two solenoid valves, and therefore the number of solenoid valves can be reduced by one compared to the conventional method. , weight reduction and space saving can be achieved at low cost.

[Brief explanation of the drawing]

FIG. 1 is a hydraulic system diagram of an embodiment in which a hydraulic distribution device according to the present invention is incorporated into a hydraulic control device for an automatic transmission of an automobile, and FIG. 2 is a mechanism principle diagram showing the structure of the portion surrounded by a dashed line. FIG. 3 is a diagram showing the principle of the mechanism of another embodiment of this part, and in the figure, 25 is a shift control valve, 37, 38 are solenoid valves, 3
9 is the first spool, 40 is the second spool, 41,
42 is a land, 43 is a third spool, 44 is a valve body, 45 is a hole, 48 is an oil drain path, 49 is a third distribution control oil path, 50 is a second distribution control oil path, and 51 is a first distribution control oil path. 52 is a first hydraulic supply path, 53
is the second hydraulic supply path, 54 and 56 are orifices, and 5
5 is a third hydraulic pressure supply path, and 59 and 60 are spools.

Claims (1)

[Claims] 1 A first spool and a second spool that are slidably fitted into one hole formed in a valve body and that face each other, and a first spool and a second spool that have two lands and that are a third spool that is slidably fitted into the hole between the third spool and is applied with a pressing force toward the first spool;
an oil drain path and a hydraulic pressure supply path that communicate in parallel with each other in the hole between the first spool and the second spool, and a hydraulic pressure supply path that communicates with the hole between the first spool and the second spool in parallel with each other; into the hole between the first spool and the third spool, and three distribution control oil passages that communicate with each other and whose communication with the oil drain passage or the oil pressure supply passage is switched depending on the position of the third spool; a first solenoid valve that controls the supply and discharge of pressure oil, and a second solenoid valve that controls the supply and discharge of pressure oil for pressing the first spool and the second spool toward the third spool. Hydraulic distribution device.