JPH02190662A - Transmission for vehicle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transmission for a vehicle, and more specifically, a continuously variable transmission for driving is provided with a shift actuator, and a sensor for detecting a shift operation position; The present invention relates to an improvement in a transmission comprising a feedback type control system including a speed setting device for determining a traveling speed.

[Conventional technology]

Conventionally, in a transmission device configured as described above, control is performed to operate the actuator until the signal value from the speed setting device and the signal value from the sensor are balanced, and usually the sensor and speed setting device each have a voltage. It is configured in a potentiometer type to output a signal (references not listed).

[Problem to be solved by the invention]

However, when the sensor and speed setting device are configured as potentiometers, long-term use can cause disconnections or short circuits in the signal lines from each, or the sensor and speed setting device themselves may malfunction. It may occur.

In other words, when used for a long period of time, the above-mentioned problems may occur due to vibrations from the vehicle body during work or contact with other parts.

If a disconnection or short circuit occurs in the signal line, the signal voltage value will rise to approximately the power supply voltage, or
Since the signal voltage value drops to zero potential, if such a problem occurs during driving, the vehicle speed may increase, so there is room for improvement from a safety standpoint.

Incidentally, it is conceivable that a similar phenomenon occurs when a failure occurs in the sensor or speed setting device.

An object of the present invention is to construct a transmission that can reliably detect the above-mentioned inconvenience and take safe measures even if the above-mentioned inconvenience occurs during driving through reasonable modification.

[Means for Solving the Problems] A feature of the present invention is that a continuously variable transmission device that adjusts the traveling speed steplessly from a stopped state to a running state is provided with an actuator for shifting operation, and the shifting operation position by this actuator is controlled. Feedback control type speed adjustment means is provided with an electric sensor for detection and an electric speed setter that is manually operated, and a detection signal from at least one of the sensor or the speed setter is Discrimination means is provided for detecting a state outside a preset detection range as an abnormal state, and when the abnormal state is detected by the discrimination means, the control of the continuously variable speed control is given priority over the control of the speed adjustment means. The present invention includes forced restoring means for controlling the actuator in order to forcibly shift the gear shift position of the device to the stop position, and its functions and effects are as follows.

[For production]

For example, if the above characteristics are configured as shown in FIG. 1, the signal lines (3
7), (38) if a disconnection or short circuit occurs, or if the signal voltage input to the control system is outside the sensing range or setting range, as in the case of a failure. The determination means (36) detects this state, and based on this detection result, the forced restoration means (B) controls the actuator (14) to control the continuously variable transmission (4).
The shift position of the vehicle will be forced to the stop position.

In other words, if the detection signals from the sensor (16) and the speed setting device (20) are outside the preset detection range, it is an abnormal state. (voltage comparator circuit in the embodiment) is provided,
Further, by detecting an abnormal state with this discrimination means (36), the forced restoration means (B) forcibly operates the shift position of the continuously variable transmission (4) to the traveling stop position, so that the traveling can be stopped even in the middle of traveling. It is possible to do this.

In addition, in FIG. 1, the 11th second analog switch (31),
(32), the neutral voltage generation circuit (27), the two switches (18), and (18) the forced restoration means (B).
) is configured.

〔Effect of the invention〕

Therefore, by relatively simple modification of discriminating means 11 by providing a forced restoration means, when an abnormality occurs in the sensor, speed setting device, and signal lines from each during driving, this abnormality can be reliably detected. A transmission system has been constructed that can take the safest action of stopping the vehicle.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Fig. 5, a pair of left and right front and rear wheels (1).

An engine (3) is installed at the front of a vehicle body (2) having a vehicle body (1), and a mechanical continuously variable transmission (4) is located at the center of the vehicle body (2).
is provided to form a travel drive system so that the driving speed can be adjusted by steplessly changing the power from the engine (3) from a stopped state to a traveling state in each of the front and rear directions, and the vehicle body (2) A driver's seat (5) is connected to the rear of the vehicle, and a lawn mower (6) is connected in a suspended state to the center of the vehicle body (2) to constitute a riding type lawn mower as an example of a vehicle.

As shown in FIGS. 3 and 4, the continuously variable transmission (4
) is an input boot 1 bar 8) to which power is transmitted from the engine (3) via an endless belt (7), and an endless belt (9).
and the front and rear wheels (1), (1) via the reduction gear (10).
It has an output pulley (11) that transmits power to the
By rotating the speed change operation shaft (4a) protruding from the side, the contact position between the plurality of built-in taper cones (not shown) and the rotating member (not shown) is adjusted, and the speed change power is extracted. It is configured like this.

Further, an arm (4b) for operating the rotating member is provided at the inner end of the speed change operation shaft (4a), and a sector gear (4b) is provided at the outer end.
12), and an electric motor (14) that drives a pinion gear (13) meshing with the sector gear (12) is attached to the continuously variable transmission (4).
is configured to be able to perform a speed change operation by driving an electric motor (14).

Furthermore, an arm member (1) provided on the sector gear (12)
5), and the continuously variable transmission (4)
A potentiometer-type sensor (16) that detects the shift operation position of the continuously variable transmission (4) is connected to the continuously variable transmission (4) via the stay (17).
), and two switches (1B), (1B) that are operated only when the sector gear (12) is out of the stop position are also attached to the device.

That is, this lawnmower is constructed so that the speed change operation can be performed by electrical control, and the control system is shown in FIG.

As shown in the figure, in this control system, the speed change pedal (
a potentiometer-type first speed setting device (20) linked to the switch (19); and the two switches (18), (18).
and the rotation of the sensor (16), a potentiometer type second speed setter (22) linked to the cruising speed setting dial (21), and the gear (10a) built in the speed reduction device (10). a pickup-type speed sensor (23) that detects the number of rotations, a sensing mechanism (24) that emits a number of pulses according to the number of rotations of the engine (3), and a mode that switches between a manual speed change mode and a cruising speed change mode. The control device (A) shown in phantom lines in the figure has an input system consisting of a switch (25) and a power source (26).
a neutral voltage generation circuit (27) that generates a neutral voltage for control based on the voltage of ), and the sensing mechanism (24
) is transmitted via an F/V conversion circuit (29), and each has a voltage comparison circuit (30) for detecting a decrease in engine speed.

The control device (A) also controls the signal from the first speed setter (20) transmitted via the first and second analog switches (31) and (32), and the second analog switch (32). ), and the signal from this circuit (33) is transmitted to a third analog switch (34) and a driver (35). Speed change is performed by driving the electric motor (14) in both forward and reverse directions via the motor.

Note that this operation is a manual shift mode system, and is selected by operating the mode switch (25).

As shown in the figure, a signal path from the first speed setting device (20) and a signal path from the sensor (16) are branched, and the voltage comparator circuit (36), (36) (discriminating means) example) is provided, and the voltage comparison circuit (36) on the setting device side is provided.
Due to causes such as disconnection or short circuit in the signal line (37) between the first speed setting device (20) and the control device (A),
If the signal voltage falls outside a preset detection range, this is detected and the first analog switch (31
), this setting system can be changed to the signal line (37).
At the same time, the neutral voltage generating means (27)
By inputting a voltage signal from the sensor to this setting system, the gear position of the continuously variable transmission (4) is forcibly operated to the stop position, and the voltage comparison circuit (36) on the sensor side
6) and the control device (A) is disconnected in the signal line (38),
If the signal voltage deviates from a preset detection range due to a cause such as a short circuit, this is detected, the second analog switch (32) is operated, and the control direction discriminating circuit ( By switching the mode of operation of (33), two input switches (18), (1
8) so that the electric motor (14) is driven in a direction in which each signal reaches zero potential, and the shift position of the continuously variable transmission (4) is forcibly operated to the stop position in the same manner as described above. It has become.

The above explanation is the shift operation in manual shift mode.
Next, the operation for forced stopping will be described. Next, the operation when the cruising speed change mode is selected by operating the mode switch (25) will be described.

As shown in the figure, since the output voltage of the second speed setting device (22) with respect to the operation stroke appears as shown in the graph of Figure 2 (A), this output voltage is shown in Figure 2 (B).
As a conversion means for converting as shown in the graph, this setting system is provided with a full wave rectifier circuit (39), and the signal from this full wave rectifier circuit (39) is sent to the fourth analog switch (4
0) to the control direction discrimination circuit (41).

Further, the signal from the speed sensor (23) is input as a voltage signal to the control direction discrimination circuit (41) via the F/V conversion circuit (42), and the voltages from the setting system and the feedback system are balanced. A signal is outputted via a fifth analog switch (43) to drive the electric motor (14) in the direction, and the fifth analog switch (43) is connected to the sensor (16) and a second speed setting device. Discrimination circuit (4) that sets the switching timing based on the signal from (22)
4), the vehicle body (2) runs at the speed set by the second speed setting device (22).

As shown in the figure, a voltage comparator circuit (45) is also provided in a branched signal path from the second speed setter (22), and this voltage comparator circuit (45) is connected to the second speed setter (22). 22
) and the control device (A) due to a disconnection or short circuit in the signal line (46), etc., when the signal voltage falls outside the preset detection range, this is detected, and the 4 analog switch (40) is operated to disconnect this setting system from the signal line (46), and at the same time input a zero potential signal corresponding to a stop to the control direction discrimination circuit (41). .

In addition, this control device (A) has manual shift mode,
The first and fourth analog switches (31) are configured to stop traveling when either a drop in the voltage of the power source (26) or a drop in the engine speed is detected during shifting in any of the cruising speed modes. , (40) from the power supply voltage drop detection circuit (28) and the voltage comparison circuit (30) for detecting a drop in engine rotational speed to the OR gate (47) installed in the operation system (40). signal is input, and if an abnormality is detected as described above (such as a break in the signal lines (37) and (38)) while driving in manual shift mode, the operation of the engine (3) will be stopped after driving has stopped. ,
In addition, the engine is configured to output a signal to each of the engine stop circuit (48) and the lamp drive circuit (50) having the warning lamp (49) so as to issue an alarm when a predetermined condition is satisfied during this stop. There is.

[Another example]

In addition to the embodiments described above, the present invention can also include part or all of the control system using a microprocessor and a program, and the transmission device can also be installed in various vehicles.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the vehicle transmission according to the present invention, in which Fig. 1 is an electric circuit diagram of the control system, Fig. 2 (a) is a graph showing the output signal from the second speed setting device, and Fig. 2 (I) is a graph representing the output signal from the full-wave rectifier circuit, Figure 3 is a schematic diagram of the travel transmission system, Figure 4 is a cross-sectional view showing the mounting structure of the electric motor, sensor, etc., and Figure 5 is a lawn mower. FIG. 2 is an overall side view of the machine. (4)...Continuously variable transmission, (14)...
・Actuator, (16)...Sensor, (2
0)... Speed setting device, (36)... Discrimination means.

Claims (1)

[Claims] A continuously variable transmission (4) that adjusts the traveling speed steplessly from a stopped state to a running state is equipped with an actuator (14) for shifting operation, and an electric sensor detects the shifting operation position by this actuator (14). (16), and
Feedback control type speed adjustment means is provided with each of the electric speed setters (20) that are manually operated, and the detection signal from at least one of the sensor (16) or the speed setter (20) is It is provided with a discrimination means (36) that detects a deviation outside a preset detection range as an abnormal state, and when the abnormal state is detected by the discrimination means (36), priority is given to control of the speed adjustment means. A vehicular transmission device comprising forced restoring means (B) for controlling the actuator (14) to forcibly change the shift position of the continuously variable transmission device (4) to a stop position.