JPH061269A - Automatic speed change control device - Google Patents

Abstract

PURPOSE:To fix a speed change gear into a neutral position to secure safety even if arithmetic control is performed by a computer control device due to the careless operation of an operating button, the failure of circuit parts and other unexpected reasons during the tilt operation of a cab. CONSTITUTION:In an automatic speed change control device taking in a speed sensor output signal, a gear shift lever position display signal and a clutch state signal so as to compute and set an optimum speed change gear, the terminal board 12 of a computer control device 1 is newly provided with an electric terminal 12a, while an arithmetic means 11 is provided with an interruption control means 11a, and a relay circuit 2 is connected to the electric terminal 12a. When a cab lock is released and ground potential arises to the electric terminal 12a, whichever state various input signals to the arithmetic means 11 are placed in, the interruption control means 11a performs interruption control for fixing the speed change gear into a neutral position with top priority.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in an automobile having a cavitating mechanism. The present invention relates to an automatic shift control device that sets a shift gear by computer control. The present invention relates to ensuring safety of a cavitating mechanism.

[0002]

2. Description of the Related Art An automatic speed change control device takes in an output signal of a speed sensor of a vehicle, a signal indicating a position of a speed change lever operated by a driver, a clutch state signal, and an engine speed signal. A computer control means for calculating and setting an optimum transmission gear is provided.

On the other hand, an automobile having a cab litt mechanism is provided with a lock means for mechanically fixing the cab to a steady position so as to prevent the cab from being inadvertently tilted.
A circuit is provided for sending an alarm signal to the driver's seat when the locked state of the locking means is released.

The vehicle must not move when the cab is tilted for maintenance.
As a driving operation, it is necessary to securely apply the parking brake before tilting the cab, but as a safety device to prevent the vehicle from accidentally moving,
A device that prevents the cab from tilting unless the transmission gear is in neutral (see Japanese Utility Model Laid-Open No. 58-146762), and a device that prevents operation when the cab lock means is in an unlocked state (actually). Kaisho 56-
No. 49678) is known.

[0005]

These conventional techniques are
All of these are safety devices such as confirming that the shift gear is not in a travelable position so that the vehicle does not move while the cab is tilted. In recent years, devices that perform automatic shift control by computer control Became popular. In order to tilt the cab and perform maintenance, it may be necessary to keep the engine running, and it is not possible to prohibit engine rotation in the tilted state.Also, tilt the cab to perform maintenance inspection. It is not appropriate that the computer control system switch is automatically turned off when performing.

Even if it is confirmed that the shift gear is in the neutral position at the stage of tilting the cab, the computer control unit performs unexpected calculation control for some reason, and the shift gear is moved to a position where it can travel. It is not always impossible to be thrown in. Rather, as a safety measure, it is certain that the transmission gear should not move from the neutral position even if the computer control device is arithmetically controlled due to an unexpected cause.

The present invention has been made against such a background, and an object thereof is to provide a device provided with safety measures for ensuring the safety of a cavitated vehicle equipped with a shift control device controlled by a computer. And

[0008]

According to the present invention, an optimum shift gear is calculated by taking in an output signal of a speed sensor of a vehicle, a signal indicating a position of a shift lever operated by a driver, and a clutch state signal. An automatic transmission control device including a setting means, which is provided with one electric terminal and which, when a ground potential is applied to the electric terminal, sets the transmission gear to a neutral position and fixes it regardless of the signals. The control means and a relay circuit for continuously applying the ground potential to the electric terminal when the cab lock means of the cab lockt mechanism of the vehicle are released are provided.

Instead of the ground potential, a DC potential in a specific range can be used.

[0010]

When the computer control device is provided with a specific electric terminal and the electric terminal has a ground potential (or a potential in a specific range, for example, a potential representing "1" or "0" of the digital circuit), Whatever the state of the input signal is, the computer control unit most preferentially executes the interrupt control to set the transmission gear to the neutral position. As a result, the computer control unit is arithmetically controlled due to inadvertent operation of the operation button such as crossing or short circuit of the harness wire, pushing of the operation button due to dropping of the article, circuit component failure, or other unforeseen circumstances. Also, the interrupt control prior to that is executed to fix the transmission gear to the neutral position.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of the present invention, and FIG. 2 is a diagram showing a tilted state of a cab according to an embodiment of the present invention.

In the embodiment of the present invention, the calculating means for taking the output signal of the speed sensor of the vehicle, the signal indicating the position of the shift lever operated by the driver, and the clutch state signal and calculating and setting the optimum shift gear. A computer control device 1 including a terminal board 1 is further provided as a feature of the present invention.
2 is provided with one electric terminal 12a, and the arithmetic control means 11 sets the transmission gear to the neutral position and fixes it when the electric potential is applied to the electric terminal 12a regardless of the signals. 11a is provided, and the relay circuit 2 is provided for continuously applying the ground potential to the electric terminal 12a when the cabling means of the cavitating mechanism of the vehicle is released. Instead of the ground potential, a DC potential in a specific range can be used.

Next, the operation of the embodiment of the present invention thus constructed will be described.

Normally, in the process in which the cab lock is released and the cab is tilted to the maximum tilt position or returned from the maximum tilt position to the normal position,
The cab lock switch 7 and the tilt limit switch 6 are in the ON state.

When the cab lock is released to tilt the cab 15, the hydraulic circuit 20 shown in FIG. 2 is switched to the hydraulic pressure raising operation, and the operation switch 3 is operated to set it to the on state, the power relay 4 is turned on. Then, the tilt motor 5 operates, the hydraulic pump 21 and the hydraulic cylinder 23 operate, and the cab 15 starts the tilting operation. When the cab tilts to the maximum tilt position, the tilt limit switch 6 is turned off, and accordingly, the power relay 4 is set to the off state and the tilt operation is stopped.

In the course of such a tilting operation, since the cab lock switch 7 is always set to the ON state, the relay circuit 2 is also set to the ON state and provided on the terminal board 12 of the computer control unit 1. A ground potential is applied to the electric terminal 12a.

When the ground potential is applied to the terminal plate 12, the interrupt control means 11a causes the speed sensor output signal a from the speed sensor, the shift lever position display signal b operated by the driver, and the clutch state indicating the state of the clutch. Regardless of the signal c, the speed change gear of the transmission 8 is preferentially set to the neutral position and fixed.

When the cab reaches the maximum tilt position, the tilt limit switch 6 is turned off and the power relay 4
Is turned off and the operation of the tilt motor 5 is stopped.

In order to return the cab from the maximum tilt position to the steady position after the predetermined work is completed, the hydraulic circuit 20 is switched to the hydraulic pressure lowering operation, and the cab 15 is tilted to the maximum tilt by the mechanical operation of the hydraulic cylinder 23 shown in FIG. When the operation switch 3 is operated to be set to the ON state while the tilt limit switch 6 is kept in the ON state until the hydraulic pump 21 and the hydraulic pump 21 are driven, the tilt relay 5 is turned on. The hydraulic cylinder 23 operates and the cab is returned to the normal position. In the process of returning to the normal position, the ground potential is continuously applied to the electric terminal 12a provided on the terminal board 12 of the computer control device 1, so that the gear of the transmission 8 is fixed to the neutral position. Stay in the state.

When the operator turns off the operation switch 3 when the cab reaches the steady position, the power relay 4 is turned off and the operation of the tilt motor 5 is stopped. Here, when the cab lock for fixing the cab is performed, the cab lock switch 7 is turned off and the relay circuit 2 is turned off. When the relay circuit 2 is turned off, the ground potential applied to the electric terminal 12a of the terminal board 12 disappears, the interrupt control means 11a becomes ineffective, and the neutral position of the transmission gear can be released.

As described above, during the tilting operation of the cab,
Regardless of what control signal is input, the neutral position of the transmission gear is fixed with the highest priority, and a safe state is maintained.

[0022]

As described above, according to the present invention, during the tilting operation of the cab, the wire crossing or short circuit of the harness wire,
Even if the computer control unit is arithmetically controlled due to inadvertent operation of operation buttons, circuit failure, or other unexpected circumstances, it is possible to execute interrupt control for fixing the neutral position of the speed change gear, which is prioritized for safety. There is an effect that can be secured.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a tilted state of a cab according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Computer control device 2 Relay circuit 3 Operation switch 4 Power relay 5 Tilt motor 6 Tilt limit switch 7 Cab lock switch 8 Transmission 11 Calculation means 11a Interruption control means 12 Terminal plate 12a Electric terminal 15 Cab 20 Hydraulic circuit 21 Hydraulic pump 22 Oil Reservoir 23 Hydraulic cylinder

Claims (2)

[Claims] 1. An automatic shift control including means for taking in an output signal of a speed sensor of a vehicle, a signal indicating a position of a shift lever operated by a driver, and a clutch state signal and calculating and setting an optimum shift gear. The apparatus is provided with one electric terminal, and when the electric potential is applied to this electric terminal, the interruption control means for setting and fixing the transmission gear to the neutral position regardless of the above-mentioned signals, and the cab lockt of the vehicle. An automatic shift control device, comprising: a relay circuit for continuously applying a ground potential to the electric terminal when the cab lock means of the mechanism is released. 2. The automatic shift control device according to claim 1, wherein the ground potential is replaced with a DC potential in a specific range.