JPH0314583Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to an overload prevention device for a transmission reverse gear.

(Prior Art and its Problems) The reverse gear of a manual transmission in an automobile receives less load during normal use than the forward transmission gears.
It takes less distance to travel backwards than forwards.

Traveling speed is lower than when moving forward.

Driving becomes more careful when reversing.

There are reasons such as.

On the other hand, if the clutch is suddenly engaged without being in a half-clutch state (hereinafter referred to as "sudden engagement"), a very large transient response torque will be generated in the drive system due to the moment of inertia of the drive system. It has long been well known that reverse gears are no exception. In fact, it is more likely that the clutch operation will fail when moving backward than when moving forward, and in this case, the clutch will be engaged suddenly and excessive torque will be applied to the reverse gear. Therefore, the reverse gear must be designed to withstand this excessive torque, and in this sense, excessive quality must be ensured.

In order to solve the above-mentioned problems and to improve the quality of reverse gears, various ideas have been made in the past. For example, there is Utility Model Application No. 58-33831. This is a technology in which the clutch automatically engages in a half-clutch state, regardless of the driver's operation. However, this technology also has the following problems.

(1) It does not operate only when reverse gear is used, but operates during all clutch operations. Therefore, when the vehicle is running, that is, when both the engine and the drive system are rotating and a half-clutch state is not necessary, the driver feels uncomfortable.

(2) If the driver operates the clutch carefully enough, this may actually induce unpleasant vehicle behavior.

In addition, as another conventional technology, there is a combination of a torque converter and a mechanical clutch, but both of these are in a fully engaged state when the engine is rotating at high speed. There is no effect in preventing generation of excessive torque.

Therefore, the present invention prevents the generation of transient response torque caused by sudden clutch engagement using the reverse gear when the vehicle is stopped and the engine is rotating at high speed, and prevents excessive torque when designing the reverse gear. The purpose is to eliminate the need to consider torque, ensure appropriate quality for normal use, and make the transmission smaller and lighter.

(Means for solving the problem) In order to achieve this objective, the present invention is configured as follows. That is, the opening and closing of each oil passage of the bypass passage which is interposed between the clutch master cylinder and the release cylinder and which allows the clutch to be engaged at a slow speed by means of an oil passage and an orifice for normal clutch operation. The oil passage opening/closing operation of the opening/closing means is controlled in accordance with various detection signals such as engine speed, whether a clutch pedal is depressed, and whether a reverse gear is selected. It was decided to configure the system by including a controller.

(Function) According to the above configuration, when conditions such as engine rotation, whether or not the clutch pedal is depressed, and whether or not reverse gear is selected, the controller performs control based on this detection signal. Switch the valve oil path. Therefore, if you depress the clutch pedal and select reverse gear while the engine is rotating at a high speed exceeding the set value, the controller will shut off the control valve's oil passage and the clutch will engage. This prevents excessive load from acting on the drive system.

(Example) Hereinafter, an example embodying the present invention will be described in detail with reference to the drawings.

In the drawing, 1 is a clutch pedal, 2 is a master cylinder, 3 is a reservoir tank, 4 is a release cylinder connected to the master cylinder 2 via an oil tube 5, and 6 is a transmission.

A control valve 7 for controlling the supply of hydraulic pressure to the release cylinder 4 is interposed in the middle of the oil tube 5 described above based on a command from a controller 17 to be described later. As shown in FIG.
divided into rooms. That is, the first chamber 10 connected to the master cylinder 2 and the release cylinder 4
A second chamber 11 communicating with the first and second chambers 1
It is divided into an intermediate chamber 12 interposed between 0 and 11. The port 13 that communicates the first chamber 10 and the second chamber 11 is connected to the first solenoid valve 14.
The second chamber 11 can be opened and closed by
A port 15 communicating between the intermediate chamber 12 and the intermediate chamber 12 can be opened and closed by a second solenoid valve 16. The operations of both solenoid valves 14 and 15 are controlled according to commands from a controller 17.

Next, the controller 17 will be explained (see FIG. 3). Connected to this controller 17 are an engine speed detection sensor 18, a reverse gear detection sensor 19 that detects whether a reverse gear is selected, and a clutch sensor 20 that detects whether a clutch is depressed. .

First, the engine rotation speed detection sensor 18 is connected to a waveform shaping circuit 21 and further connected to a comparator 23 through an F-V conversion circuit 22. Then, the comparator 23 can compare the magnitude of this input signal with a reference voltage determined by the setter 24 and invert the output. However, the setting device 24 is set at a level corresponding to an appropriate engine speed that does not generate excessive torque harmful to the drive system. Also, comparator 2
The output side of No. 3 turns on the second solenoid valve 16.
It is connected to the first AND gate 25 which is turned off.

The reverse gear detection sensor 19 is connected to the other input side of the first AND gate 25 via the first isolator 26 . Further, a detection signal from the sensor 19 is connected via a first inverter 27 to an OR circuit 28 that turns the first solenoid valve 14 on and off.

The clutch sensor 20 is connected via a second isolator 29 to a second inverter 30, the output of which, together with the output of the first inverter 27, is connected to a second AND.
It is connected to the gate 31 and further connected to the other input side of the OR gate 28.

Subsequently, the functions and effects of this example formed as described above will be specifically explained.

When the gear position of the transmission 6 is selected other than reverse, the reverse gear detection sensor 19 is in the off state, regardless of whether the detection signal on the engine rotation speed detection sensor 18 side is on or off. The output of the first AND gate 25 becomes "0", and as a result, the second solenoid valve 16 closes the port 15. On the other hand, at this time, the detection value from the reverse gear detection sensor 19 is inverted by the first inverter 27, and the output becomes "1".
Since it is input to OR gate 28, OR gate 2
Regardless of the output level of the other input side of the clutch sensor 8 (detected value from the clutch sensor 20), the output of the gate 28 becomes "1", and as a result, the first solenoid valve 14 opens the port 13. Therefore, the first
Since the chamber 10 and the second chamber 11 communicate with each other, and the master cylinder 2 and the release cylinder 4 communicate with each other, normal clutch operation is possible.

Now, when the clutch pedal 1 is depressed and the gear position is selected to reverse, the reverse gear detection sensor 19 and the clutch sensor 20 are turned on, but both the first and second inverters 27 and 30 are turned on.
At this point, each output becomes "0". For this reason,
Since both inputs of the OR gate 28 are "0", the first solenoid valve 14 is in a closed state. When the clutch pedal 1 is released from this state, the force of the clutch sensor 20 becomes "0", and the second inverter 30 inputs "1" to the second AND gate 31, but the other input of this AND gate 31 is
Since it is still "0", the output of the OR gate 28 remains "0". Therefore, since the first solenoid valve 14 is in a closed state, the clutch remains disengaged.

Here, whether or not the clutch is engaged depends on the engine speed. That is, the output signal of the engine rotation speed detection sensor 18 is shaped by a waveform shaping circuit 21, and then subjected to frequency-voltage conversion by an F-V conversion circuit 22. If this output level exceeds the reference voltage set by the setter 24, the first AND gate 2
Since the level input to the gate 25 is "0", the output of the gate 25 is "0", and the second solenoid valve 16 remains closed. Therefore, even if reverse gear is selected while the engine is running at high speeds, the clutch will not engage. On the other hand, when the engine speed becomes low and the output of the engine speed detection sensor 18 falls below the reference level of the setting device 24, the level input to the first AND gate 25 through the comparator 23 becomes "1".
becomes. Further, since the reverse gear is selected, the other inputs of the gate 25 are at the "1" level, so the output is "1" and the second solenoid valve 16 is turned on. Therefore, the port 1 between the second chamber 11 and the intermediate chamber 12
5 opens. However, since the pressure oil in the clutch system is sent to the release cylinder 4 through the orifice 8, the clutch engages loosely and smoothly starts the vehicle.

(Effects of the Invention) As detailed above, in the present invention, it is possible to avoid excessive torque to the drive system caused by a driving error when the vehicle is reversing. For this reason, unlike in the past, the reverse gear is not required to have excessive quality, and can be made to have appropriate quality. In addition, even if the driver makes a mistake while reversing the vehicle, the clutch does not suddenly engage, which prevents the vehicle from starting suddenly, giving the driver sufficient time to apply the brakes, and causing a vehicle accident. can be avoided.

[Brief explanation of the drawing]

FIG. 1 is an overall view of the apparatus of this example, FIG. 2 is a sectional view schematically showing a control valve, and FIG. 3 is an electric circuit diagram of the controller. 2... Master cylinder, 4... Release cylinder, 7... Control valve, 14, 16...
First and second solenoid valves (opening/closing means), 17
……controller.

Claims (1)

[Scope of utility model registration request] Opening and closing of each oil passage of the bypass passage which is interposed between the clutch master cylinder and the release cylinder and which allows the clutch to be engaged at a slow speed by means of an oil passage and an orifice for performing normal clutch operation. A control valve equipped with an opening/closing means, and a controller that controls the oil passage opening/closing operation of the opening/closing means in accordance with various detection signals such as engine speed, whether a clutch pedal is depressed, and whether a reverse gear is selected. A transmission reverse gear overload prevention device characterized by: