JPS5845578B2 - Engine overrun warning and prevention device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a warning and prevention device for preventing troubles caused by overruns in automobile engines, particularly diesel engines.

It is common for automobiles to use engine braking while exiting a vehicle, but in particular when a truck is fully loaded and the vehicle is unloading, the engine brake is used when operating the transmission's gear lever to downshift the gear range. There was a high risk that the system would overrun and be damaged.

Furthermore, in diesel passenger cars and the like, due to driver ignorance, there is a strong possibility that the engine will overrun if the gear is downshifted from a high speed comparable to that of a gasoline passenger car.

For this reason, some gasoline-powered vehicles, especially those with rotary engines, have been equipped with engine overrun prevention devices, but this simply detects the engine speed and turns off the ignition system's power when it reaches a predetermined speed. It is designed to turn off the engine and cannot be used when downshifting the transmission when exiting the vehicle or when a diesel engine overruns.

In order to prevent the engine of a diesel engine vehicle from overrunning, the present invention aims to reduce the number of rotations of the top gear shaft of the transmission or the countershaft connected thereto when the driver attempts to downshift the gear range. A rotation sensor for detecting is connected to a first DA converter, and the converter is connected to an alarm via a first comparator, and when the number of rotations of the top gear shaft exceeds a predetermined value, the alarm is activated. If it is not sufficient to make the system operate and issue an alarm, the first comparator is connected to the relay coil of a relay switch equipped with a relay contact corresponding to each gear range, and the vehicle speed is detected. The sensor is connected to a second DA converter, and the movement of the shifter rod of the transmission is locked through a second comparator group provided for each gear range of the transmission and a relay contact corresponding to each gear range. When the rotation speed of the top gear shaft or countershaft exceeds a predetermined value, the output of the first DA converter causes the first
When the vehicle speed exceeds a predetermined speed for each of the second comparators, the output from the second DA converter activates one of the second comparators. The above output activates the electromagnetic device to lock the shifter rod of the transmission belonging to each comparator, thereby preventing a downshift to a dangerous gear position (range) during a shift.

Embodiments of the present invention will be specifically described in detail below with reference to the drawings.

1 is a rotation sensor that measures the top gear rotation speed (or counter gear rotation speed) in a car's transmission.
For example, a pulse voltage obtained from the rotation of gear teeth is obtained as a rotational speed signal.

A vehicle speed sensor 2 is used to obtain a pulse signal having a frequency proportional to the vehicle speed from the rotation of the propeller shaft or the main shaft of the transmission connected thereto.

In addition, 3 and 4 are D-A converters, and each rotation sensor 1
, to integrate the pulse signal from the vehicle speed sensor 2 and convert it into an output voltage proportional to the frequency of the pulse signal, that is, an analog voltage.

Kl, 2. 3. 4 is a comparator, of which K1.
2. 3 compares the voltages input from the respective A terminals and B terminals, and operates to output the current from the power source 5 as an output current only when the A terminal voltage is higher than the B terminal voltage.

Also, comparator 4 compares the X terminal voltage and Y terminal voltage, and
The relay contact 7b operates to flow an output current only when the terminal voltage is higher, sounds the buzzer 6 as an alarm, and energizes the relay coil 7a of the relay switch 7.

7c and 7d are turned on.

Also, 8, 9.10 are 1st, 2nd t, 3r respectively
The electromagnetic device d is an electromagnetic device that, when energized, pushes out the respective stopper shafts 8a, 9a, 10a, and is installed on the upper part of the transmission 11 to shift the shift fork 12 for gear shifting.
It operates to restrict sliding movement of the shifter rod 13 to which the shifter rod 13 is attached.

Note that R1 to R6 are resistors for obtaining a predetermined circuit voltage.

The operation of the embodiment of the present invention having the above configuration will be explained as follows.
While the vehicle is currently running, 1s of the transmission
t, 2ndy Set the voltage corresponding to the maximum vehicle speed in the 3rd gear with the resistors R1 to R6 based on the voltage of the power supply 5, and connect each B terminal of 1 to 3 to the comparator and the X of 4 to the comparator, respectively. The voltage is applied to the terminal.

Therefore, a pulse signal proportional to the vehicle speed is obtained from the vehicle speed sensor 2 from the rotation of the transmission side of the speedometer cable, the main shaft, or the propeller shaft.

The vehicle speed pulse signal from the vehicle speed sensor 2 is converted into an analog voltage proportional to the vehicle speed pulse signal in the next DA converter 4, and then sent to each comparator. 2. The voltage is constantly applied to the A terminal of No. 3 while the vehicle is running.

On the other hand, from the rotation sensor 1, a pulse signal of engine rotation corresponding to the engine rotation speed detected from the rotation speed of the top gear shaft of the transmission (or the rotation speed of the counter gear) is converted into the pulse signal by the DA converter 3. It is converted into a proportional analog voltage, and the output signal is applied to the comparator at the Y terminal of 4, but if it is lower than the set voltage currently applied to the X terminal of 4, the output signal is applied to the comparator at the Y terminal of 4. 4 never works properly.

However, when the engine speed increases and the analog voltage from the Y terminal, which is converted by the D-A converter 3 from the engine rotation pulse signal detected by the rotation sensor 1 based on the top gear rotation speed, is higher. 4 conducts to the comparator and energizes the alarm 6 and relay coil 7a.

Therefore, the alarm 6 warns the driver in advance that an overrun will occur, and the comparator 1. 2° Of K3, only the comparators where the B terminal voltage to which each set voltage is applied are lower than the A terminal voltage are conductive and are connected to the upper position of the transmission via each relay contact 7b, 7c, 7d. i.e. 1s for each gear position installed in the Cortland box.
Among the electromagnetic devices t, 2nd, and 3rd, the stopper shafts (8a, 9a, 10a
) is pushed out to lock the movement of the shifter rod 13 and act to prevent an inappropriate gear change that would cause the engine to overrun.

By the way, in the case where a car is currently running at high speed in the top gear range and gears down to the 3rd gear range, there is a risk that the engine will overrun if the vehicle is geared down from the high speed state to the 3rd gear range.

Therefore, in such a state, a pulse as a vehicle speed signal is detected by the vehicle speed sensor 2 and sent to the D-A converter 4.
The analog voltage converted by the converter is high due to the large vehicle speed, but the number of comparators is 1. 2. If the A terminal voltage from the D-A converter 4 is higher than the B terminal voltage of 3 to the comparator whose B terminal has the highest set voltage among 3, then the comparator 3 is in a conductive state, and ( Of course, both comparators Kl and 2 are in a conductive state.

) Moreover, since the rotation speed of the top gear in the transmission increases to the rotation speed indicating a preset dangerous condition, the rotation pulse from the rotation sensor 1 is transmitted to the D-A converter 3.
The analog voltage proportional to the rotational speed of the top gear converted by the comparator and applied to the Y terminal of 4 becomes higher than the set voltage applied to the X terminal, and 4 becomes conductive to the comparator and an alarm is activated. 6 and energizes the relay coil 7a to turn on the relay bet points 7b, 7c, and 7d.

Therefore, through 3, the comparator is in a conductive state as described above.
Since the third electromagnetic device 10 is energized through the relay contact 7b, the stopper shirt NOa pops out and prevents the shifter rod 13 from moving.

Therefore, even if an attempt is made to shift down from the top gear range to the 3rd gear range by operating the change lever, the shift fork 12 does not move and the 3rd gear cannot be engaged.

Also, when the vehicle speed signal voltage is such that 3 is conductive to the comparator, 1 is connected to the comparator. Since 2 is also conductive, the 1st and 2nd electromagnetic devices 8 and 9 also operate, so in the above case, the 1st
Gearing down to any of the y, 2nd, and t3rd gear ranges is prevented.

In this way, a gear down to a gear range that is suitable for the vehicle speed or less is not established.

Therefore, when the vehicle speed decreases by applying the brake, etc., the vehicle speed pulse signal from the vehicle speed sensor 2 becomes D-A.
When the analog voltage converted by the converter 4 becomes lower than the voltage of the comparator 3, which is the highest among the set voltages of the B terminal,
The comparator 3 is in a cut-off state.

Therefore, even if the relay coil 7a is energized and the relay contact 7b is ON, the 3rd electromagnetic device is not energized and the stopper shaft 10a does not protrude, so the driver cannot operate the change lever. The shifter rod 13 becomes movable, and the shift fork 12 attached to the shifter rod 13
Accordingly, it becomes possible to downshift from the top gear range to the 3rd gear range.

Note that the above operation similarly operates when downshifting from the 3rd gear range to the 2nd gear range and from the 2nd gear range to the 1st gear range.

As described above, the device of the present invention detects the actual running speed and detects the rotational speed to prevent engine overrun, not from the engine itself, but from the engine via the clutch to the top gear shaft or countershaft of the transmission. Since it is taken from the rotational speed, when the vehicle speed is to shift to a gear range that would cause the engine to overrun, the clutch is generally disengaged at the time of the shift, and the top gear or counter gear is separated from the engine. Since the rotational speed of the shaft is detected by a rotation sensor and a gear shift to an inappropriate gear is prevented, it is possible to prevent engine overrun without actually overrunning the engine. Damage to the vehicle,
This is extremely useful as it can prevent the occurrence of personal accidents caused by such problems.

[Brief explanation of the drawing]

Fig. 1 is an electric circuit diagram showing an embodiment of the device of the present invention;
The figure is an exemplary diagram in which the rotation sensor, vehicle speed sensor, and 1st and 3rd electromagnetic devices shown in the first figure are installed in the transmission. 1: Rotation sensor, 2: Vehicle speed sensor, 3, 4: DA converter, 4 on K1-: Comparator, 6: Alarm, 7: Relay switch, 8, 9.10: Electromagnetic device, 11 Nidoran transmission , 12: Shift fork, 13 Nijifuta-rod.

Claims (1)

[Claims] 1. A top gear shaft in a transmission (
A rotation sensor that detects the rotation speed of the top gear shaft (or a countershaft connected thereto) is connected to a DA converter, and the converter is connected to an alarm via a comparator to detect when the rotation speed of the top gear shaft exceeds a predetermined value. An engine overrun warning device characterized in that the alarm is activated when the engine overrun occurs. 2 Top gear shaft in transmission (
A rotation sensor that detects the rotation speed of a countershaft (or a countershaft connected thereto) is connected to a first DA converter, and the converter is connected via a first comparator to a relay contact point corresponding to each gear range. In addition to connecting the relay coil of the relay switch, the vehicle speed sensor that detects the vehicle speed is connected to the second D.
A second comparator group connected to the A converter and provided with the converter for each gear range of the transmission, and a relay contact of a relay switch corresponding to each gear range of the transmission, respectively.
It is connected to each electromagnetic device installed to lock the movement of the shifter rod of the transmission, and when the rotation speed of the top gear shaft or counter shaft exceeds a predetermined value, the output of the first DA converter causes the first When the vehicle speed exceeds a predetermined speed for each of the second comparators, the output from the second DA converter activates one of the second comparators. An engine overrun prevention device characterized in that the above output is used to activate an electromagnetic device to lock a shifter rod of a transmission belonging to each comparator.