JPH0542279Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention includes a first cylinder chamber and a second cylinder chamber, and guides air into the first or second cylinder chamber to move the piston to the first or second position. an actuator for positioning the piston in a neutral position by guiding air into both cylinder chambers; and position detection means for detecting the first, second and neutral positions of the piston. Regarding improvements.

[Prior art] As an automatic system that achieves both fuel efficiency and easy drive, sensors such as an engine rotation sensor and vehicle speed sensor and an actuator for operating the clutch and transmission are added to the conventional mechanical clutch and transmission. Mechanical automatic systems are known in which these are controlled by a control unit to change shifts.

FIG. 1 is a drawing showing an embodiment of the present application, of which known parts will be explained in order to understand the invention of the present application.

In Figure 1, transmission cover 1
, a shift fork shaft 2 driven by a shift actuator 20 is provided parallel to the axis of the transmission body (not shown), and a striker 3 linked to the shift fork (not shown) is provided at one end of the shift fork shaft 1. It is provided.

In the shift actuator 20, first and second cylinder chambers (hereinafter referred to as chambers) A and B are defined by a piston 21, and each chamber and the piston 21
Annular pistons 22a and 22b that can move together with the piston 21 are interposed between the first and second electromagnetic valves (hereinafter referred to as valves) 23a and 22b, which are normally open and in the exhaust state. It is adapted to be selectively connected to the air tank 24 via 23b.

The piston rod 25 of the piston 21 is integrally connected to the shift fork shaft 2, and between the piston rod 25 and the transmission cover 1 are located the first, second and neutral positions of the piston 21, that is, the striker 3, that is, the shift fork shaft 2. Position detection means for detecting positions X, Y and neutral position N is provided. This detection means consists of three electric switches, namely a Y position switch 4Y, an X position switch 4X and a neutral position switch 4N, which are adapted to engage and close a recess formed in the piston rod 25.
The figure shows neutral position switch 4N.
indicates that it is closed. Then, when the first valve 23a is energized and opened to guide the air in the air tank 24 to the first chamber A, the piston 21 moves to the right in the figure together with the piston 22a to move the shift fork shaft 2, that is, the striker 3 to the first chamber A. Position for example 3
position to shift position Y. When the air is introduced into the second chamber B, the piston 22b moves to the left together with the piston 21, and the striker 3 is positioned at the second position, for example, the fourth gear shift position X. Also, both chambers A and B
When air is introduced into the neutral position N, the striker 3 is positioned at the neutral position N.

By the way, in this device, when shifting from 3rd speed to 4th speed, for example, when the second valve 23b is opened and the Y position switch 4Y is turned OFF,
The so-called one-lung type, in which the first valve 23a is also opened to determine whether the neutral position switch 4Y is off, and then the first valve 23a is closed, or the both valves 23a and 23b are opened to determine whether the neutral position switch 4N is on. However, there are two so-called double-lung control systems in which the first valve 23a is closed after determining ON.

However, in the single-lung type, the output of the actuator 20, that is, the gear pulling force, is large as shown by the solid line in FIG. 4, and in addition, the first valve 23a opens with a delay. This is because the opening responses of the first and second valves 23a and 23b are unbalanced. There is a problem in that the striker 3 does not stop at the neutral position but moves too far and enters the fourth gear at high speed, and the synchronization condition, that is, the balk condition, is not satisfied and gear noise occurs.

On the other hand, the present applicant in Utility Application No. 60-26361,
We are proposing an automatic transmission system that solves the problem of not being able to shift gears.

Generally, a transmission using an air actuator with a three-position detection device is well known, and is disclosed, for example, in Japanese Utility Model Application Publication No. 59-43744. However, as described above, this known technique cannot prevent gear noise when the striker goes too far from the neutral position.

Further, Japanese Patent Application Laid-Open No. 60-95242 discloses a technique for controlling the piston speed of an actuator in order to establish a synchronization condition, but in this known technique, the operating time is It is long and difficult to control.

[Problem to be Solved] Therefore, an object of the present invention is to provide an automatic transmission for a vehicle that has an actuator that uses two cylinders to position it in a neutral position, and that can prevent gear noise due to excessive piston movement during gear shifting. We are here to provide you with the equipment.

[Means for Solving the Problems] According to the present invention, a first cylinder chamber and a second cylinder chamber are provided, and air is guided to the first or second cylinder chamber to position the piston at the first or second position. An actuator that guides air into the chamber to detect the neutral position of the piston, passes through the chamber without stopping, and positions the piston again in neutral; and a position detection means that detects the first, second, and neutral positions of the piston. The automatic transmission for a vehicle provided therein includes a ROM that stores a predetermined time required for the piston of the position detecting means to leave the first or second position and return to the neutral position; Or, when positioning from the second position to the second or first position, it is stored in the ROM from the time when it is detected that the piston of the position detection means is away from the first or second position and is in the neutral position. Control means is provided for supplying air to the actuator so as to position the piston at the second or first position after a predetermined period of time has elapsed.

[Explanation of action and effect] Therefore, when the piston goes past the neutral position and returns, the predetermined time is stored in the ROM, and the shift operation is performed after the predetermined time has elapsed. As a result, a synchronization condition can be established and gear noise can be prevented.

[Preferred embodiment] When implementing the present invention, the predetermined time is 500 microseconds when shifting to 1st gear, 200 microseconds when shifting to 2nd gear, and 50 microseconds when shifting to 3rd gear. is preferable.

[Examples] Examples of the present invention will be described below with reference to the drawings. Figure 1 shows a fully automatic transmission in which the present invention is implemented, with each position switch 4X, 4Y,
4N and each valve 23a, 23b are connected to a control unit 40 which is a control means. A feature of the present invention is the control mode of the control unit 40, which will be explained below.

In FIG. 2, a control unit 40 is provided with a central processing unit (CPU) 41, which controls each switch, each valve, the vehicle speed sensor 30, and the accelerator opening sensor 31 via an input/output device (I/O). A predetermined time T required for the shift map and the striker 3, that is, the piston 21, which will be described later in FIG. 500 microseconds when shifting gears, and 500 microseconds when shifting to 2nd gear.
A ROM 43 is provided that stores 200 microseconds and 50 microseconds when shifting to third gear. The central processing unit 41 then controls the vehicle speed sensor 3.
0 and the detection signal from the accelerator opening sensor 31, the shift change is determined according to the shift map stored in the ROM 43, and an operating signal is output to each valve 23a, 23b. When positioning to the 3rd gear, the striker 3 moves away from the 2nd gear and is in the neutral position after the predetermined time (50 microseconds) from the time of detection based on the signal from the neutral position switch 4N. It has become possible to control shifts quickly.

Next, the operation will be explained mainly with reference to FIG. 3, taking as an example the case of shifting from 3rd speed to 4th speed.

When the control unit 40 determines to shift from 3rd speed to 4th speed, it disengages the clutch by known control and then opens the first valve 23a (step
S1). As a result, the air in the air tank 24 is guided to the first chamber A, the piston 21 moves to the right, the 3rd speed position switch 4Y is turned off, and when a neutral signal is output (step S2), the second valve 2
3b is opened to open both valves 23a and 23b, and a brake is applied to the rightward movement of the piston 21 to return it to the neutral position even if it passes the neutral position (step S3). Next, when the N signal continues for a predetermined time T (50 microseconds in this case) (step S4), the second valve 23b is closed (step S5).
When the Y position switch 4Y is turned on and the shift to 4th gear is completed (step S6), the clutch is connected (step S7) and the first valve 23a is closed (step S8).

[Summary] As explained above, according to the present invention, the piston, that is, the striker, always stops at the neutral position for a predetermined period of time, so it is not possible to engage a gear at high speed, and as a result, after being stopped and held at neutral, it is Since the gearing operation is performed at the speed,
Synchronization conditions are met and gear noise is prevented.
Note that although the embodiment has been described with respect to upshifting, the same applies to downshifting.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention;
FIG. 2 is a block diagram of the control unit, FIG. 3 is a control flowchart, and FIG. 4 is an explanatory diagram of conventional so-called single-lung type and double-lung type shift modes. A...First chamber, B...Second chamber, 2...Shift fork shaft, 4X, 4Y, 4N...Position switch, 20...Shift actuator, 23a...First valve, 23b...second valve,
40...Control unit.

Claims (1)

[Scope of utility model registration request] It has a first cylinder chamber and a second cylinder chamber, and air is guided into the first or second cylinder chamber to move the piston into the first cylinder chamber.
Or a vehicle equipped with an actuator that positions the piston at the neutral position by guiding air to the second position and position detecting means that detects the first, second, and neutral positions of the piston. In an automatic transmission, a predetermined time required for a piston of a position detection means to move away from a first or second position, detect a neutral position, pass without stopping, and return to the neutral position again is memorized. It has a ROM that
Or, when positioning from the second position to the second or first position, it is stored in the ROM from the time when it is detected that the piston of the position detection means is away from the first or second position and is in the neutral position. An automatic transmission for a vehicle, comprising: control means for supplying air to an actuator so as to position the piston at the second or first position after a predetermined period of time has elapsed.