JP3539181B2 - Emergency device of automatic transmission - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an emergency operating device for an automatic transmission, which is suitable for use in a mechanical automatic transmission.
[0002]
[Prior art]
BACKGROUND ART Conventionally, a mechanical automatic transmission that performs automatic transmission using a gear mechanism similar to a manual transmission has been developed and put into practical use. In such a mechanical automatic transmission, a clutch actuator for automatically connecting / disconnecting a clutch is provided, and a gear shift actuator for changing a meshing state (i.e., a gear position) of a gear is provided. Automatic shifting is performed by controlling via electric signals.
[0003]
These actuators operate using a fluid pressure such as an air pressure or a hydraulic pressure as a drive source, and are configured to control the operation by changing a supply state of the fluid pressure. The gear shift actuator is provided with a plurality of electromagnetic valves for controlling the supply state of the fluid pressure, and the gear shift actuator and the electromagnetic valves constitute a gear shift unit (or GSU).
[0004]
By the way, in such a gear shift unit of a mechanical automatic transmission, two systems of electromagnetic valves are provided in response to an abnormal situation such as failure of the electromagnetic valve. For example, if the gear shift unit requires six solenoid valves MVa to MVf, the first solenoid valve group MVa1, MVb1,..., MVf1 and the second solenoid valve group MVa2, MVb2, , MVf2 are provided in parallel, and at the time of controlling the gear shift actuator, the solenoid valve group of one of the systems is to be controlled, and the solenoid valve group of the other system is on standby as a backup solenoid valve.
[0005]
If one of the solenoid valves fails while controlling one group of solenoid valves, the control target is switched to the other group of solenoid valves and the shift control is continued. That is, by providing two solenoid valves in this way, the solenoid valve group of one system and the solenoid valve group of the other system mutually function as backup electromagnetic valves.
[0006]
Incidentally, such a control signal to the solenoid valve is output from a control unit (ECU) as a control means. In the ECU, a target shift speed is set by an arithmetic unit (CPU) provided therein, and the CPU sets an operation control signal to each solenoid valve so as to shift to the target shift speed.
Therefore, if the ECU or the CPU itself breaks down, it becomes impossible to set a control signal, and it is conceivable that shift control becomes impossible or traveling becomes impossible.
[0007]
Therefore, in order to cope with such a situation, an emergency switch (emergency operation means) is conventionally provided. Here, the emergency switch outputs a signal for simultaneously and forcibly operating the solenoid valves of both systems prior to the control signal from the CPU.
Further, in the case where the above-described two-system solenoid valve is provided, for example, one of the first-system solenoid valves (for example, MVa1) fails and one of the second-system solenoid valves (for example, MVb2) becomes defective. When a failure occurs, the actuator cannot be normally operated by using any of the first and second solenoid valve groups.
[0008]
In such a case, the second system solenoid valve MVa2 may be operated for MVa, and the first system solenoid valve MVb1 may be operated for MVb. In order to independently operate desired solenoid valves, complicated control logic is required.
Therefore, in such a case, by operating both of the two solenoid valve groups by the forced operation signal output by the driver operating the emergency switch, another solenoid valve corresponding to the failed solenoid valve is operated. Is activated, and the solenoid valves of the respective systems perform a mutual backup function. For example, in the above case, since both the solenoid valves MVa1 and MVa2 and both the solenoid valves MVb1 and MVb2 are driven, the actuator can be operated by the normal solenoid valves MVa2 and MVb1.
[0009]
FIG. 3 is a schematic block diagram for explaining a conventional technique provided with such an emergency switch. The function of the emergency switch will be briefly described below with reference to FIG.
In the figure, 101 is a control means (or a controller or simply ECU) for controlling the operation of the actuator, 102 is a CPU provided in the control means 101, 103 is an emergency switch as emergency operation means, and 104 is other Sensors and switches. Further, 105 is a GSU, MV1 and MV2 are a first system solenoid valve and a second system solenoid valve attached to the GSU 105, MV1 is a solenoid valve representative of the solenoid valves MVa1 to MVf1, and MV2 is a solenoid valve. This is an electromagnetic valve representatively showing the electromagnetic valves MVa2 to MVf2.
[0010]
First, at normal times, information from the various sensors 104 is taken into the ECU 101, and various calculations and processes are performed by the CPU 102 in the ECU 101 to set the target shift speed. Then, a drive signal is output from the CPU 102 to one of the solenoid valve groups so that the target shift speed is achieved, whereby the shift speed is changed.
[0011]
If one of the solenoid valves fails, the control target is switched to the other solenoid valve by the CPU 102, and the speed control is continued by the other solenoid valve.
Further, when one of the solenoid valves of both systems fails and the backup solenoid valves function normally (for example, when MVa1 and MVb2 fail), that is, the solenoid valves of both systems are simultaneously driven. If the actuator can be operated by doing so, the driver operates the emergency switch 103 so that the solenoid valves of both these systems are simultaneously driven to perform a gear shift.
[0012]
Here, the emergency switch 103 is, for example, a dial-type switch engraved with the number of the shift speed. By setting the dial to the number of the shift speed desired by the driver, the emergency switch 103 is directly connected to the solenoid valves MV1 and MV2. A shift control signal (forced operation signal) is output.
That is, by operating the emergency switch 103, a signal for forcibly activating the solenoid valves MV1 and MV2 of both systems is output in preference to the control signal from the CPU 102. You can do it.
[0013]
In the unlikely event that the ECU 101 or the CPU 102 itself breaks down, the driver can directly switch the gear by operating the emergency switch 103.
On the other hand, as shown in the figure, the emergency switch 103 is also connected to the CPU 102, and when the emergency switch 103 is operated, the emergency switch 103 is operated separately from the above-described forced operation signal. Is output to the CPU 102.
[0014]
Here, such an operation signal is output to the CPU 102 for the following reason. That is, as shown in FIG. 3, the forced operation signal from the emergency switch 103 is output to the solenoid valves MV1 and MV2 through the ECU 101 on the circuit connection, but this control signal is output to the CPU 102 in the ECU 101. Is a control signal set by the driver using the emergency switch 103.
[0015]
On the other hand, the CPU 102 constantly monitors the operating states of the solenoid valves MV1 and MV2, and determines that the solenoid valve that is not operating according to the control signal from the CPU 102 is out of order.
On the other hand, since the operation of the electromagnetic valves MV1 and MV2 by the emergency switch 103 is not based on the control signal from the CPU 102, the electromagnetic switch MV1 is operated by the emergency switch 103 when the CPU 102 is functioning normally. , MV2 is driven, it is determined that the solenoid valves MV1 and MV2 have been operated without permission, and the malfunction of the solenoid valves is erroneously determined. In this case, since it is determined that the two systems MV1 and MV2 including the backup have failed in the solenoid valve MV, it is determined that the shift is not possible, and the vehicle cannot travel.
[0016]
In this case, the emergency switch 103 does not function sufficiently. Therefore, as described above, the CPU 102 captures the operation signal of the emergency switch 103 and detects the operation of the emergency switch 103. In this case, even if the two systems of the solenoid valves MV1 and MVa2 are driven at the same time, a failure is not determined.
[0017]
[Problems to be solved by the invention]
By the way, such a conventional technique has the following problems.
For example, when the harness between the emergency switch 103 and the ECU 101 is short-circuited (short-circuited) even though the ECU 101 and the solenoid valves MV1 and MV2 are functioning normally, the emergency switch 103 is turned on. , The forced operation signal is output, and the two solenoid valves MV1 and MV2 are forcibly driven.
[0018]
In such a case, since the operation signal is not output from the emergency switch 103, the CPU 102 determines that the two solenoid valves MV1 and MV2 are operated without permission even though the emergency switch 103 is not operated. As a result, there is a problem in that it is erroneously determined that the solenoid valves MV1 and MV2 have failed, and the vehicle cannot travel.
Of course, in the case described above, although the ECU 101 and the solenoid valves MV1 and MV2 are functioning normally, and there is actually no hindrance in running, the emergency measures provided as emergency measures are taken. It is desired to avoid a situation in which the vehicle cannot run due to a short circuit in the harness of the juncture switch 103.
[0019]
The present invention has been devised in view of such a problem, and provides an emergency operating device for an automatic transmission, which is capable of avoiding the inability of the vehicle to travel due to a short circuit of the emergency operating means with a simple configuration. With the goal.
[0020]
[Means for Solving the Problems]
In the emergency operating device for an automatic transmission according to the present invention, normally, the transmission control means controls the shift state of the transmission according to the driving state of the vehicle. Then, the transmission driving means is driven in accordance with a control signal from the transmission control means, and the shift state is changed. Further, in an emergency, when the driver operates the emergency operation means, a forced operation signal is output, and the transmission driving means operates prior to the control signal from the transmission control means. At this time, the forced operation permission means outputs the forced operation signal to the transmission drive means only when both the operation signal and the forced operation signal are output from the emergency operation means. Even if the operation signal is output, the forced operation permission means does not output this forced operation signal to the transmission driving means, thereby preventing malfunction of the transmission driving means. Thus, it is possible to avoid a situation in which the vehicle cannot travel.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an emergency operation device for an automatic transmission according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a functional block diagram schematically showing the configuration of the main portion, and FIG. 5 is an example of a flowchart for explaining the operation of FIG. Since the automatic transmission to which the present device is applied is a known technology, a detailed description of the automatic transmission will be omitted.
[0022]
In FIG. 1, reference numeral 1 denotes a control means (or a controller or simply an ECU), 2 denotes a CPU as a transmission control means provided in the ECU 1, 3 denotes an emergency switch as an emergency operation means, and 4 denotes other switches. Sensors and switches. Reference numeral 5 denotes a gear shift unit (GSU), MV1 and MV2 denote a first-system solenoid valve and a second-system solenoid valve attached to the GSU 5, and MV1 represents the solenoid valves MVa1 to MVf1 described in the related art. Similarly, the solenoid valve MV2 is a solenoid valve representatively representing the solenoid valves MVa2 to MVf2. Further, the GSU5 and the MV1 and MV2 constitute a transmission drive unit.
[0023]
Also, the components having the same names as the components shown in FIG. 3 have the same functions as those described with reference to FIG. 3, and the description thereof will be omitted.
Now, as shown in FIG. 1, in the present apparatus, an AND circuit 6 as a forced operation permitting means is added to the conventional technique shown in FIG.
[0024]
The AND circuit 6 is configured so that both the forced operation signal and the operation signal from the emergency switch 3 are input. The AND circuit 6 receives both of these two signals. Only when this is done, a forced operation signal is output to each of the solenoid valves MV1 and MV2.
With this configuration, even if the harness between the emergency switch 3 and the ECU 1 is short-circuited and a forced operation signal is output from the emergency switch 3, the forced operation signal is output to the AND circuit 6. Therefore, the AND circuit 6 determines that the condition for forcibly operating the solenoid valves MV1 and MV2 is not satisfied, and does not output the forcible operation signal.
[0025]
As described above, the AND circuit 6 determines whether the forced operation signal from the emergency switch 3 is a normal signal output by the operation of the driver or an erroneous signal output due to a short circuit of the harness or the like. Therefore, it is possible to avoid a situation in which the vehicle cannot travel due to an erroneous signal.
The emergency operating device of the automatic transmission according to one embodiment of the present invention is configured as described above. Therefore, during normal times, that is, when the entire system of the automatic transmission is functioning normally, various sensors 4 are used. From the ECU 1 and the CPU 2 processes the information to set a target gear position.
[0026]
Then, the CPU 2 outputs a control signal to the solenoid valve (electromagnetic valve group) MV1 of one of the systems attached to the GSU 5 so that the target shift speed is attained, thereby executing shift control.
If one of the solenoid valves MV1 fails, the control signal from the CPU 2 is output to the backup solenoid valve MV2 of the other system, whereby the shift control is continued.
[0027]
Further, if the solenoid valve group of one system and the solenoid valve group of the other system fail, and the solenoid valve of another system corresponding to the failed solenoid valve is normal, the driver sets the emergency switch 3 By simultaneously operating the solenoid valve groups of both systems in response to the forced operation signal, the driver performs manual shifting.
When the ECU 1 or the CPU 2 itself breaks down, the driver operates the emergency switch 3 to output a forced operation signal, and the solenoid valve is controlled in preference to the control signal set by the CPU 2. You. In the emergency switch 3, the driver can select a gear position, so that even in an emergency, the gear position can be manually changed according to the driver's intention.
[0028]
In the present device, for example, when the harness between the ECU 1 and the emergency switch 3 is short-circuited and the forced operation signal is output regardless of the driver's intention, the AND circuit 6 outputs the forced operation signal. Since the output is prohibited, the malfunction of the solenoid valves MV1 and MV2 is prevented.
That is, in this case, since the operation signal of the emergency switch 3 is not input to the AND circuit 6, the AND circuit 6 determines that the condition for outputting the forced operation signal is not satisfied, and outputs the forced operation signal. It is forbidden.
[0029]
As a result, malfunction of the solenoid valve due to a short circuit of the harness of the emergency switch 3 can be prevented. Further, by preventing such a malfunction of the solenoid valve, it is possible to avoid a situation in which the vehicle cannot travel. That is, conventionally, when the solenoid valve malfunctions due to a short circuit of the harness of the emergency switch 3 or the like, the operation signal of the emergency switch 3 is not input to the CPU 2 and only the forced operation signal is output. Therefore, the CPU 2 determines that the solenoid valves MV1 and MV2 have been operated without permission, and determines that the solenoid valves MV1 and MV2 have failed. In this case, since there is no backup electromagnetic valve, the CPU 2 determines that shift control cannot be performed and the vehicle cannot run.
[0030]
On the other hand, in the present device, the forced operation signal is output to the solenoid valves MV1 and MV2 of the GSU 5 only when the forced operation signal is output based on the operation of the emergency switch 3, so that such an electromagnetic valve Can be prevented, and a situation in which the vehicle cannot travel can be avoided.
Now, the operation of the present apparatus will be described with reference to the flowchart of FIG. 2. First, in step S1, it is determined whether or not a forced operation signal has been output. Proceeding to S2, normal shift control is executed.
[0031]
If the forced operation signal has been output, the process proceeds to step S3 to determine whether the operation signal of the emergency switch 3 has been output. Then, when the operation signal is output, it is determined that the emergency switch 3 has been operated by the driver's intention, the forced operation signal is output in step S4, and the emergency shift control is executed in step S5. You.
[0032]
If it is determined in step S3 that the operation signal of the emergency switch 3 has not been output, it is determined in step S6 that an abnormality such as a short circuit of the harness has occurred. It activates a warning light in the panel to notify the driver of the abnormality.
As described above, according to the emergency operating device of the automatic transmission according to the present invention, the solenoid valves MV1 and MV2 due to the short circuit of the harness of the emergency switch 3 and the like are provided with the simple configuration of providing the AND circuit 6 as the forced operation permitting means. Can be prevented from malfunctioning. Further, by preventing such malfunctions of the solenoid valves MV1 and MV2, it is possible to prevent the CPU 2 from erroneously determining that the solenoid valves MV1 and MV2 have failed and to avoid a situation in which the vehicle cannot travel. You can.
[0033]
The emergency operating device of the automatic transmission according to the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above description, a case has been described in which two systems of electromagnetic valve groups constituting the transmission driving means are provided, but the present invention is applied to an automatic transmission in which only one system of such electromagnetic valve groups is provided. However, the number of systems of the solenoid valve group is not limited. In the above description, the case where the present invention is applied to a mechanical automatic transmission has been described. However, the present invention may be applied to, for example, an automatic transmission using fluid pressure.
[0034]
【The invention's effect】
As described above in detail, according to the emergency operating device of the automatic transmission of the present invention, the forced operating signal is output to the transmission driving means only when the forced operating signal is output based on the operation of the emergency operating means. With the extremely simple configuration of providing the forced operation permitting means, it is possible to prevent a malfunction of the transmission driving means due to a short circuit of the harness of the emergency operating means. Further, by preventing such erroneous operation of the transmission driving means, it is possible to prevent the transmission control means from erroneously determining that the transmission driving means has failed, and to avoid a situation in which the vehicle cannot travel. There is an advantage that can be.
[Brief description of the drawings]
FIG. 1 is a functional block diagram schematically showing a main configuration of an emergency operating device of an automatic transmission according to an embodiment of the present invention.
FIG. 2 is an example of a flowchart for explaining an operation of a main part function in the emergency operating device of the automatic transmission as one embodiment of the present invention.
FIG. 3 is a functional block diagram schematically showing a configuration of a conventional emergency operating device of an automatic transmission.
[Explanation of symbols]
2 CPU as transmission control means
3 Emergency switch as emergency operation means 5 Gear shift unit (GSU) constituting transmission drive means
6. AND circuits MV1 and MV2 as forcible operation permitting means Solenoid valves constituting transmission drive means

Claims (1)

Transmission control means for controlling a shift state of the transmission according to a driving state of the vehicle;
Transmission driving means driven in response to a control signal from the transmission control means to change the shift state;
Emergency operation means which is operated by the driver in an emergency and outputs a forced operation signal and an operation signal for operating the transmission driving means in preference to a control signal from the transmission control means;
Only when it is detected that both the forcible operation signal and the operation signal have been output, forcible operation permitting means for permitting the forcible operation of the transmission driving means by the forcible operation signal is provided. Characterized by the emergency operating device of the automatic transmission.

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