JPH0128366Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] The present invention relates to an automatic transmission for a vehicle in which a shift rod operated by a conventional manual shift lever can be automatically operated.

An automatic transmission automatically controls a hydraulic circuit using the output of a microcomputer based on input signals such as engine load, rotation speed, and vehicle speed, and this hydraulic circuit operates a hydraulic actuator that drives a shift rod. For example, JP-A-54-
Although it has already been proposed in Publication No. 96659, the hydraulic actuator that drives the shift rod and its hydraulic control device can be installed in the conventional Cordland box part without changing the main parts of the gear transmission, and can be removed from the gear box. In order to save space, the oil tank is required to have a flat structure with a small amount of upward protrusion and to be integrally formed adjacent to the hydraulic actuator.

The purpose of this invention is to solve the above problems.
The purpose of the present invention is to provide an automatic transmission in which an oil tank is integrally provided between a housing that supports an electromagnetic switching valve and a housing that supports an electromagnetic switching valve by eliminating unnecessary internal parts of a control box.

For this reason, the configuration of the present invention is to overlap and connect the control boxes that are integrally equipped with the hydraulic actuators that drive the shift rods on the upper side of the gear boxes, and to use the recesses as oil tanks provided between the hydraulic actuators of the control boxes. A housing equipped with an electromagnetic switching valve that controls the hydraulic circuit of a hydraulic actuator is placed on top of the control box and sealed.

The present invention will be explained based on examples. As shown in FIG. 2, the automatic transmission according to the present invention is equipped with hydraulic actuators 21 to 23 above the gear box of the known gear transmission in place of the conventional Cortland box (in the case of a five-speed forward transmission). ) The control box 2 is connected to the flange portion 2a by bolts, and further includes six electromagnetic switching valves 31 to 33 on the upper side of the control box 2 for controlling the hydraulic circuits of the respective hydraulic actuators 21 to 23.
Housing 3 with 31a to 33a (Figure 5)
are combined.

As shown in FIG. 1, a main shaft (not shown) is supported by bearings 5 and 6 on the front and rear end walls of the gear box 4, and clutch sleeves 7 to 9 of a synchronous clutch mechanism are supported on the main shaft. Clutch sleeve 7-9
Shift arms 7a, 8a, which move the
9a are supported by separate shift rods 10, and when these shift rods 10 are pushed leftward or rightward from the neutral position shown in the figure by the hydraulic actuators 21 to 23, respectively, the gears are shifted to a predetermined gear position. It is becoming more and more common.

The shift rod 10 is slidably supported on the end wall of the control box 2 at one end, and connected to a hydraulic actuator 21 at the other end. The hydraulic actuator 21 is constructed by fitting a large diameter piston 36 into a large diameter cylinder 34 formed at the left end of the control box 2, and fitting a small diameter piston 37 integral with the shift rod 10 into a small diameter cylinder 35. Further, an intermediate piston 38 is fitted into a large diameter cylinder 36 having a cylindrical portion. The end of the large diameter cylinder 34 is closed by a lid 39 via a sealing member. A passage 41 connected to an end chamber of the large-diameter cylinder 34 is switched and connected to a hydraulic power source P or an oil tank R via an electromagnetic switching valve 31. The stepped portions 34a of the large diameter cylinder 34 and the small diameter cylinder 35 are connected to the oil tank R via a passage 42. A passage 44 connected to an end chamber of the small diameter cylinder 35 is switched and connected to a hydraulic power source P or an oil tank R via an electromagnetic switching valve 31a. Solenoid switching valve 31, 31a
are attached to the housing 3 together with the electromagnetic switching valves 32 to 32a and 33 to 33a of the other hydraulic actuators 22 and 23.

A recess 43 is formed by removing the flesh between the hydraulic actuators formed in the control box 2. The recess 43 is closed by the housing 3 connected to the upper side of the control box 2, thereby forming an oil tank R. This oil tank R is connected to the passage 45 through a conduit and to a suction port of a hydraulic pump (not shown). In addition, the oil tank R is connected to the shaft hole 4 through the passage 46.
7 to lubricate the sliding portion of the shift rod 10.

As shown in FIG. 3, each shift rod 10 is provided with a detent mechanism that elastically holds it in three positions. That is, shift rods 1 on both sides
For 0, the bolt 5 attached to the side wall of the control box 2
A spring and a ball 59 are housed inside the shift rod 6, and the ball 59 is elastically engaged in the recess 58 of the shift rod 10. A similar detent mechanism is provided for the center shift rod 10, but in this case the bolt 56 is attached to the upper wall of the control box 2, as shown in FIG.

Further, an interlock mechanism 60 is provided so that when any one of the shift rods 10 is operated from the neutral position to a desired gear stage, the other shift rods 10 are held at the neutral position. That is, holes 6 extending perpendicularly to the shift rods 10 are formed in the intermediate wall 2b of the control box 2 that supports each shift rod 10.
In addition, holes 63 are provided in the central shift rod 10, and recesses 64 are provided in the sides of the shift rods 10 on both sides. An elongated interlock pin 65 is fitted into each hole 62 and a short interlock pin 66 is fitted into each hole 63, so that any one of the shift rods 10
When the shift rod 10 is operated from the neutral position to a predetermined gear position, the interlock pins 65 and 66 are removed from the recess 64 or hole 63 of the shift rod 10 and are engaged with the hole 63 or recess 64 of the other shift rod 10. It's summery.

A recess 43 serving as an oil tank R is formed on the upper surface of the control box 2 as shown in a grid pattern in FIG. The oil tank R is provided with passages 42 and 44 at its bottom, and is closed by overlapping and connecting the housing 3 to the mounting surface 68.

As shown in FIG. 5, each hydraulic actuator 2
In order to connect both end chambers 1 to 23 to the hydraulic power source P or the oil tank R, an electromagnetic switching valve is connected to each end chamber. That is, in the case of the hydraulic actuator 21, pressure oil is sent from the hydraulic source P to the large diameter cylinder 34 via the electromagnetic switching valve 31a, or the oil in the large diameter cylinder 34 is returned to the oil tank R. Further, pressure oil is sent from the hydraulic source P to the small diameter cylinder 35 via the electromagnetic switching valve 31, or the oil in the small diameter cylinder 35 is returned to the oil tank R. Each electromagnetic switching valve 31, 31a is normally in the state shown in the figure by the force of the return spring 27, and the end chamber is connected to the oil tank R.
When the valve body is energized, the valve body is moved against the force of the return spring 27, and the hydraulic actuator 2
The first cylinder chamber is configured to be connected to a hydraulic pressure source P.

Next, the operation of the automatic transmission according to the present invention will be explained using the hydraulic actuator 21 as a representative. In FIG. 5, when the electromagnetic switching valve 31a is energized, pressure oil is supplied from the hydraulic source P to the large diameter cylinder 34,
The shift rod 10 is pushed to the right by the small diameter piston 37, and meshing of the gears of a predetermined gear position, that is, the first gear position, is achieved.

The electromagnetic switching valve 31a is demagnetized and the electromagnetic switching valve 31
When excited, the pressure oil of the hydraulic source P flows into the electromagnetic switching valve 31.
The oil in the large diameter cylinder 34 is returned to the oil tank R. As the small-diameter piston 37 and the large-diameter piston 36 are pushed to the left, the shift rod 10 follows suit, and the gears of the predetermined gear position, that is, the reverse gear, are brought into engagement.

When the electromagnetic switching valves 31 and 31a are energized, pressure oil is sent to both end chambers and returned to the neutral position shown. In this way, a pair of electromagnetic switching valves 31 to 3 provided in the hydraulic circuit of each hydraulic actuator 21 to 23
By energizing one or both of 3, 31a to 33a, the operating position of each hydraulic actuator can be switched to three positions.

[Effects of the invention] As described above, the present invention combines control boxes that are integrally equipped with a hydraulic actuator for driving a shift rod on the upper side of a gear box, and connects the control boxes by overlapping each other, and creates an oil tank between the hydraulic actuators of the control boxes. The recess is sealed by overlapping the housing with the electromagnetic switching valve that controls the hydraulic circuit of the hydraulic actuator on the upper side of the control box, so the hydraulic circuit is formed just by connecting the hydraulic pump, and the structure is simple and easy to assemble. is easy.

The device as a whole is lightweight and small, and there is little protrusion upward from the gear box, so the protrusion from the floor of the vehicle can be suppressed.

In addition, if the solenoid switching valve malfunctions,
You can easily remove the housing and replace it.

[Brief explanation of drawings]

Fig. 1 is a side sectional view omitting the main body of the gear transmission according to the present invention, Fig. 2 is a front view thereof, Fig. 3 is a sectional plan view thereof, and Fig. 4 is a plan view of the control box. 5
The figure is a hydraulic circuit diagram of the automatic transmission. R... Oil tank, 2... Control box, 3... Housing, 4... Gear box, 10... Shift rod, 1
2...Feed passage, 21-23...Hydraulic actuator, 28...Return passage, 31, 31a, 32,
32a, 33, 33a...Solenoid switching valve, 34...
Large diameter cylinder, 35...Small diameter cylinder, 36...
Large diameter piston, 37...Small diameter piston, 38...
Intermediate piston, 43... recess.

Claims (1)

[Scope of utility model registration request] The control boxes, which are integrally equipped with the hydraulic actuators that drive the shift rods, are stacked on top of each other on the upper side of the gear boxes, and the recesses as oil tanks provided between the hydraulic actuators of the control boxes are placed on the upper side of the control boxes. An automatic transmission characterized by overlapping and sealed housings equipped with electromagnetic switching valves that control hydraulic circuits.