JPH10338043A - Automatic transmission for construction equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic transmission for construction equipment, which is capable of suppressing impact and vibration of the equipment due to an abrupt speed reduction when an operating device is operated during traveling of the equipment, and improving the workability especially in a fine working mode. SOLUTION: In an automatic transmission and its method of the construction equipment, when an operating device is operated during the period of traveling of the construction equipment such as an exavator, the speed is changed to the first stage and the second stage depending on the degree of load applied to a traveling motor 9 during traveling and operating of the equipment in order to distribute the oil quantity to the operating device and the traveling motor 9, and remove the impact applied to the equipment due to the conversion to the first stage, and further the speed is always fixed to the first stage when the equipment does not travel. The transmission is provided with a solenoid valve 8 for adjusting the swash plate-tilt angle of the traveling motor 9 to change the speed of the traveling motor 9, a sensor for judging if the equipment should travel or not, and a controller 12 for generating speed-change signals to the solenoid valve 8 by the detection signal of the sensor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to construction equipment (Cons).
More particularly, the present invention relates to an automatic transmission and method for construction equipment. More specifically, an excavator
When a work device such as a boom, an arm, or a bucket is operated while running construction equipment such as a vehicle, a shock applied to the equipment is removed by a sudden decrease in traveling speed. Transmission and method for automatic transmission.

[0002]

2. Description of the Related Art A traveling motor of construction equipment such as an excavator is shifted by changing a tilt angle of a swash plate provided therein. In other words, the tilt angle of the traveling motor is changed depending on the degree of load applied to the traveling motor during traveling, and the speed is changed to the first speed or the second speed.

FIG. 1 shows a conventional automatic transmission used for an excavator. The controller 12 determines whether the equipment can travel or work based on inputs from the traveling state detecting means 16 and the work state detecting means 17. If it is determined by the work state detecting means 17 and the running state detecting means 16 that the equipment is only traveling, the traveling motor 9 is automatically switched to the first and second speeds by the controller 12 according to the magnitude of the load applied to itself. It is shifted.

When the operating device 7 is operated during operation by using the operating device operating means (11; a normal joystick), the direction of the control valve 6 is switched from a neutral state to a state in which the amount of oil is supplied to the operating device 7. The operating oil supplied from the pump 2 to the traveling motor 9 is distributed and supplied to the working device 7. The distribution of the oil amount causes the speed of the traveling motor 9 to rapidly decrease, and at this time, the controller 12 forcibly switches the traveling motor 9 to 1 level.
It will be changed to fast.

[0005]

Such a sudden change in speed due to the distribution of the oil amount and the shift to the first speed causes an impact on the entire hydraulic system, causing severe jerk in the equipment. In addition, the durability of the equipment may be reduced, and the life of the equipment may be shortened and the life of the equipment may be shortened.

On the other hand, during the running of the equipment, the current equipment state is changed to a fine mode for precision work.
In this case, there is a problem that the fine work cannot be performed smoothly when the traveling motor is shifted to the first speed and the second speed.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned object, and when operating a working device while the equipment is traveling, an oil amount is distributed to the working device and a traveling motor, and a shift to a first speed is performed. It is an object of the present invention to provide an automatic transmission and method for construction equipment for suppressing shock and vibration of equipment due to a rapid decrease in speed, and particularly for improving workability in a fine work mode.

[0008]

According to one embodiment of the present invention, the inclination of the swash plate of the traveling motor is adjusted according to the load applied to the traveling motor to shift the gear. An automatic transmission for construction equipment comprising a solenoid valve to be driven, running state detecting means for determining whether or not the equipment can run, and a controller for sending a shift signal to the solenoid valve according to a signal from the running state detecting means. , The controller is:
When the traveling state detecting means detects that the state of the equipment is traveling, the solenoid valve is controlled so that the speed of the traveling motor is changed to the first speed and the second speed depending on the load applied to the traveling motor. Is turned on, and when the traveling state detecting means detects that the state of the equipment is stopped, the traveling motor is fixed to the first speed state regardless of the load applied to the traveling motor. An automatic transmission for construction equipment, characterized in that a solenoid valve is turned off.

According to another aspect of the present invention, there is provided an automatic transmission method for construction equipment for shifting gears by adjusting a tilt angle of a swash plate of a travel motor. Detecting whether the motor can run or not;
When the traveling motor is in operation, turning on a solenoid valve for shifting the traveling motor so that the first and second speeds are shifted according to the degree of load applied to the traveling motor; And automatically turning off the solenoid valve so that the traveling motor is fixed at the first speed regardless of a load applied to the traveling motor when the motor is stopped. Is provided.

Another feature of the automatic transmission method according to another aspect of the present invention is that, when the traveling motor is traveling and the work mode of the equipment is set to the fine work mode at the same time, the traveling motor is always set to one. Turning off the solenoid valve so as to be fixed at a high speed.

If the controller is out of order, the driver can manually fix the gear to the first speed using a shift switch.
Alternatively, it is possible to make it possible to automatically shift at the first speed and the second speed.

[0012]

FIG. 2 schematically illustrates an automatic transmission for construction equipment according to a suitable embodiment of the present invention. The pump 2 driven by the engine 1 supplies hydraulic oil to the traveling motor 9 via the first control valve 5 operated by the traveling device operating means 10, and at the same time, the second operating by the working device operating means 11. The operating oil is supplied to the working device 7 via the control valve 6. The swash plate tilt angle of the traveling motor 9 is adjusted by the solenoid valve 8, and a signal is received by the controller 12 via the first relay 13 and the second relay 14.

When the traveling detecting means 16 detects that the equipment is traveling, the controller 12 operates as follows.
The relay 13 is turned off. As a result, the solenoid valve 8 is turned on, and the speed is automatically shifted to the first speed and the second speed depending on the load applied to the traveling motor 9. On the other hand, when the running detection means 16 detects that the equipment is stopped, the controller 12
Turn on. As a result, the solenoid valve 8 is turned off, and the first speed is fixed regardless of the load applied to the traveling motor 9.

FIG. 3 is a control flowchart illustrating a method of automatically shifting construction equipment according to a preferred embodiment of the present invention. In step 1, the process proceeds to step 2 upon receiving a signal from the traveling state detecting means 16. In step 2, it is determined whether or not the equipment is currently running, based on the signal of the running state detecting means 16 received in step 1, and if the equipment is in the running state, the process proceeds to step 3; otherwise, the process proceeds to step 4. In step 3, the first relay 13 is turned off so as to turn on the solenoid valve 8 for adjusting the inclination angle of the swash plate of the traveling motor 9, and the first and second speeds are automatically switched to the first speed and the second speed depending on the load applied to the traveling motor 9. The process is completed so that the shift is performed. In step 4, the first relay 13 is turned on so that the solenoid valve 8 is turned off, and the traveling motor 9 is turned on.
Thus, the process is completed so that the traveling motor 9 is always maintained at the first speed regardless of the load condition. The above process is repeated at regular time intervals.

Referring to FIGS. 4 and 5, an automatic transmission and method for construction equipment according to another embodiment of the present invention are schematically illustrated. FIG. 4 has a structure similar to that of the automatic transmission shown in FIG. 2 except that a work mode setting means 18 is provided. Referring to FIGS. 4 and 5, the work mode setting means 18 detects that the equipment is in the running state by the travel detection means 16 and, when the work mode of the equipment is the fine work mode, detects the equipment and drives the travel motor. Fix to first gear. Conversely, when the equipment is detected to be in the traveling state by the travel detecting means 16 and the work mode of the equipment is not the fine work mode but another work mode, this is sensed and the travel motor is switched to the first and second speeds. The gears are changed to high speed.

[0016]

As described above, according to the present invention, the shift of the traveling motor is performed in the first speed and the second speed depending on the degree of the load applied to the traveling motor during traveling by the controller judging only the traveling state of the equipment. In this way, when the vehicle is not traveling, by maintaining the traveling motor at the first speed, it is possible to suppress the impact and vibration of the equipment due to fluctuations in the amount of hydraulic oil generated when operating the working device while the equipment is traveling. As a result, the fatigue of the driver's work can be reduced, and the durability and life of the equipment can be improved. Further, even when the equipment is in a running state, when the work mode is the fine work mode, the running motor is fixed at the first speed, so that there is an advantage that fine work such as lifting work can be performed smoothly. .

Further, when the controller is out of order, there is another advantage that the driver can manually shift the equipment to the first speed or automatically shift to the first speed and the second speed by using the shift switch 15.

[0018]

[Brief description of the drawings]

FIG. 1 is a structural diagram schematically illustrating an automatic transmission for construction equipment according to the related art.

FIG. 2 is a structural diagram schematically illustrating an automatic transmission for construction equipment according to a suitable embodiment of the present invention.

FIG. 3 is a flowchart schematically illustrating a method of automatically shifting construction equipment according to a suitable embodiment of the present invention.

FIG. 4 is a structural diagram schematically illustrating an automatic transmission for construction equipment according to another embodiment of the present invention.

FIG. 5 is a flowchart schematically illustrating an automatic transmission method of the automatic transmission with construction equipment according to FIG. 4;

[Explanation of symbols]

 8 Solenoid valve 9 Traveling motor 12 Controller 15 Speed change switch 16 Running state detecting means 18 Work mode setting means

Claims (5)

[Claims] 1. A solenoid valve for shifting gears by adjusting a tilt angle of a swash plate of the travel motor according to a degree of a load applied to the travel motor; a traveling state detecting means for determining whether the equipment can travel; An automatic transmission for construction equipment comprising a controller for sending a shift signal to the solenoid valve according to a signal from the traveling state detecting means, wherein the controller is configured such that the state of the equipment is traveling by the traveling state detecting means. Is detected, the solenoid valve is turned on so that the shift of the traveling motor is performed in the first speed and the second speed depending on the degree of the load applied to the traveling motor, and the state of the equipment is changed by the traveling state detecting means. If it is detected that the vehicle is at a stop, the traveling motor is set to 1 regardless of the load applied to the traveling motor.
An automatic transmission for construction equipment, wherein the solenoid valve is turned off so as to be fixed at a high speed state. 2. The equipment includes a work mode setting means for selecting a work mode, wherein the controller detects that the equipment is traveling by the traveling state detection means, and controls the controller by the work mode setting means. The automatic transmission according to claim 1, wherein the first gear is fixed to the first gear when the equipment is set to the fine work mode. 3. If the controller is out of order, a separate shift switch is used to allow the driver to manually shift the equipment to the first gear or automatically shift to the first gear and the second gear. Automatic transmission for construction equipment. 4. A method of automatically shifting construction equipment for shifting gears by adjusting a tilt angle of a swash plate of a traveling motor; detecting whether the traveling motor is allowed to travel; A step of turning on a solenoid valve for shifting the traveling motor so that the first and second speeds are shifted according to a degree of a load applied to the traveling motor; if the traveling motor is stopped, An automatic shifting method for construction equipment, comprising: turning off the solenoid valve so that the traveling motor is fixed at the first speed regardless of a load applied to the traveling motor. 5. The automatic transmission method according to claim 1, wherein when the traveling motor is traveling and at the same time the work mode of the equipment is set to the fine work mode, the solenoid is set so that the traveling motor is always fixed to the first speed. 4. The method of claim 3, further comprising turning off the valve.