JPS6347538Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a runaway prevention device for an automobile with an automatic transmission.

<Background of the invention> Automobiles with automatic transmissions are widely used because they are easy to operate. In automobiles with automatic transmissions, the transmission mechanism between the engine and the drive wheels is disconnected when the gear lever is set to the neutral or parked position, but when the gear lever is placed in the forward or reverse position, the transmission mechanism between the engine and the drive wheels is disconnected. The structure is such that the engine is connected to the drive wheels, and the driving force of the engine is transmitted to the drive wheels.

The gear shift lever is provided with a lock mechanism for holding the shift lever in each position. In other words, to change from the neutral or parked position to the forward or reverse position, a lock release button attached to the gear shift lever is generally pressed, and this operation releases the lock mechanism and allows the gear change to be switched to another position. There is.

The advantage of cars with automatic transmissions is that you can shift the gear lever from the neutral or park position to the forward or reverse position without operating the clutch, and then press the accelerator to increase the engine speed. It is at the point of moving forward or backward. On the other hand, this advantage has a major disadvantage as described below.

<Conventional Disadvantages> In other words, while automatic transmissions offer ease of driving in that the shift lever can be put into the drive position without operating the clutch, they have the disadvantage that the shift lever can be put into the drive position even when the engine speed is high while the vehicle is stopped.

If such an operation is performed, the vehicle may start suddenly and run out of control, which may result in a serious accident.

<Purpose of the invention> This invention aims to provide an automobile with an automatic transmission that will not cause the above-mentioned runaway accidents.

<Summary of the invention> This invention detects three conditions: the car is stopped, the engine speed is higher than the specified speed, and the gear shift lever is in the neutral or parked position. Then, the gear shift lever is locked, and in this state, the gear shift lever cannot be changed to the drive position.

<Example of the invention> Fig. 1 shows an example of the invention. In the figure, reference numeral 1 indicates a vehicle speed sensor, and reference numeral 2 indicates vehicle speed determining means for receiving a signal output from the vehicle speed sensor 1 and determining whether the vehicle speed is zero. That is, as the vehicle speed sensor 1, for example, a speedometer can be used. The speedometer has a magnet that rotates in proportion to the vehicle speed, and the vehicle speed sensor 1 can be configured to have a structure in which the rotation of this magnet is detected by a pickup coil. The vehicle speed determination means 2 can be configured by, for example, a retriggerable multivibrator. In other words, a rotation detection pulse is applied from the vehicle speed sensor 1 to a retriggerable multivibrator whose reversal and return time is set to a long time, for example, about 2 to 3 seconds. Since the rotating magnet built into the speedometer is made to rotate at a relatively high speed compared to the rotational speed of the wheels, the speed sensor 1 detects the speed in less than 2 to 3 seconds when the car is moving at a small speed. Generates a pulse with a frequency of 1. Therefore, the retriggerable multivibrator is retriggered when the car is moving at low speed, and continues to output, for example, an L logic. When the vehicle speed becomes zero, vehicle speed sensor 1
The pulse will no longer be output, and the retriggerable multivibrator will no longer be retriggered. As a result, the retriggerable multivibrator returns to inversion 2 to 3 seconds after the last pulse applied, and
Output logic.

3 indicates a sensor that detects the engine speed. For example, an ignition coil can be used as this sensor. In other words, the ignition coil generates pulses with a frequency proportional to the engine speed. This pulse is extracted and the frequency of the pulse is converted into a DC voltage signal with a level proportional to the frequency by a frequency-voltage converter 4,
The voltage conversion output is given to the determining means 5. This determining means 5 can be constituted by, for example, a voltage comparator. A positive polarity setting voltage source 6 is connected to the inverting input terminal of the voltage comparator, and the frequency-voltage converter 4
The output of is given to the non-inverting input terminal.

By configuring the determination means 5 in this way, when the engine rotation speed is lower than the specified rotation speed, the output voltage of the frequency-voltage converter 4 is lower than the voltage of the set voltage source 6, so the determination means 5 performs L logic. Output. On the other hand, when the rotational speed of the engine is faster than the specified rotational speed, the output voltage of the frequency-voltage converter 4 becomes higher than the voltage of the set voltage source 6. The output of the result determining means 5 is inverted to H logic.

Reference numeral 7 indicates a position detecting means for the gear shift lever. In other words, the switch 8 is turned off when the gear shift lever 21 (see FIG. 2) is in the neutral position or the parking position, and outputs an H logic signal at this time. When the gear shift lever is shifted to the drive position, the switch 8 is turned on and outputs L logic.

9 indicates that the vehicle speed determination means 2 described above indicates that the vehicle speed is zero, that the engine rotation determination means 5 indicates that the engine rotation speed is higher than a specified value, and that the gear shift lever is in the neutral or parking position. A condition detection means for detecting that conditions are met is shown. This condition detecting means 9 can be constituted by, for example, an AND circuit. The outputs of the vehicle speed determining means 2, the rotation speed determining means 5, and the shift lever position detecting means 7 are applied to this AND circuit.

Therefore, the detection means 9 outputs H logic when the vehicle speed is zero, the engine rotation is higher than the specified value, and the gear shift lever is in the neutral or parking position.

The output of the detection means 9 is applied to an amplifier 12 via a switch 11, and the output of the amplifier 12 excites and drives, for example, an electromagnetic solenoid 13.

The amplifier 12 provides an exciting current to the electromagnetic solenoid 13 when the H logic is applied to its input. When the electromagnetic solenoid 13 is energized, it attracts the movable rod 14. The movable rod 14 includes, for example, a link mechanism 1.
5, the pawl 16 is engaged with the locking mechanism of the gear shift lever, and the gear shift lever 21 is brought into the locked state.

Figure 2 shows the locking mechanism of the gear shift lever. Second
In the figure, 21 indicates a gear shift lever. A push button 23 is provided on the operating knob 22 of the speed change lever 21, and by pressing the push button 23, a pin 24 provided at the bottom moves downward. The pin 24 engages with notches 26, 27, 28, and 29 formed in the lock plate 25 to maintain the gear shift lever 21 in the set position.
That is, for example, the notch 27 is in the neutral position, 26
may be in the retracted position, 28 in the forward position, 29 in the forward position, and so on.

Normally, if the push button 23 is pressed, the gear shift lever 2
1 can be placed in any position.

In this device, when the electromagnetic solenoid 13 is energized, the pawl 16 protrudes, and the pawl 16 is connected to each notch 26, for example.
It is inserted into a long hole 30 formed in communication with 29. By inserting the claw 16 into the elongated hole 30, in this state, the pin 24 is prevented from moving downward even if the push button 23 is pressed. Therefore, for example, if the pawl 16 is inserted into the elongated hole 30 while the pin 24 is engaged with the notch 27 that holds the neutral position, the pin 24 will not move downward even if the push button 23 is pressed, so that the shift lever will not move. 21 in other positions, that is,
It becomes impossible to convert to either the backward or forward position.

<Operations and Effects of the Invention> As explained above, according to this invention, the vehicle speed is zero, the engine rotational speed is higher than the specified value, and the operating lever 21 is in the neutral position or the parking position. When this is determined, H logic is output from means 2 and 5, and H logic is also output from position detection means 7, so that the output of condition detection means 9 becomes H logic. When this H logic signal is applied to the amplifier 12 and the electromagnetic solenoid 13 is excited, the pawl 16 moves in the direction in which it protrudes, and the pawl 16 is inserted into the elongated hole 30 formed in the lock plate 25.
is inserted. Therefore, in this state, even if the push button 23 is operated, the pin 24 is prevented from moving downward, so the shift lever 21 cannot be moved to another position, that is, forward movement.
Cannot be converted to any position of retreat.

On the other hand, when the vehicle speed is zero and the engine speed is lower than the specified speed, the output of the determining means 5 is inverted to L logic. Therefore, the output of the condition detection means 9 is L
As a result of this logic, the electromagnetic solenoid 13 becomes de-energized. When the electromagnetic solenoid 13 is de-energized, the movable rod 14 is operated in the protruding direction by the force of the spring, and this movement is changed direction by the link mechanism 15 and transmitted to the pawl 16, so the pawl 16 retreats and closes the lock plate. It is discharged from a long hole 30 formed in 25.

In this way, if the engine speed is lower than the specified value, the pawl 16 will be ejected from the elongated hole 30, so in this state, pressing the push button 23 will release the pin 24.
is moved downward and disengaged from the notch 27. Therefore, the speed change lever 21 can be changed to a desired position, that is, a forward or backward position.

As explained above, according to this invention, when the engine speed is higher than the specified value while the vehicle is stopped, the shift lever 21 is locked to prevent the shift operation, thereby preventing accidents such as the vehicle running out of control. There isn't. Therefore, even those who are not familiar with automatic transmission vehicles can drive safely.

In addition, the vehicle speed determining means 2 is provided so that the vehicle speed determining means 2 outputs the H logic only when the vehicle speed is zero, so even if the gear shift lever is placed in the neutral position while driving, the vehicle speed determining means 2 will output the L logic. Since it is outputting, the electromagnetic solenoid 13 is not excited. Therefore, there is no risk of inconveniences such as the shift lever 21 becoming locked while the vehicle is running.

In addition, a switch 11 is provided in front of the amplifier 12,
This switch 11 controls the amplifier 1 as required.
Since it is configured so that L logic can be applied to the input of switch 2, it can be used, for example, to temporarily suspend the operation of the automatic locking device by operating switch 11 during maintenance, or to intentionally make a sudden start when escaping from a rough road.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of this invention, and FIG. 2 is a perspective view for explaining the mechanism of the main part of this invention. 1...Vehicle speed sensor, 2...Vehicle speed determination means, 3
...Engine speed sensor, 4...Frequency-voltage converter, 5...Engine speed determination means, 7...
Gear shift lever position detection means, 9...condition detection means,
12...Amplifier, 13...Electromagnetic solenoid.

Claims (1)

[Scope of Claim for Utility Model Registration] A. In a vehicle with an automatic transmission, B. Vehicle speed determination means for detecting that the vehicle is stopped based on a signal from a vehicle speed sensor, and C. (D) a gear shift lever position detector that detects whether the gear shift lever is in the neutral or parking position; condition detecting means for detecting three conditions: the engine speed is higher than the specified speed, and the gear shift lever position detecting means is set to the neutral position or the parking position; A runaway prevention device for a motor vehicle with an automatic transmission, comprising: locking means for locking the state of the shift lever when the condition detecting means detects a predetermined condition.