JPH0330024B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a rapid transmission device for a tractor shovel during operation.

<Prior Art> Conventionally, in a tractor shovel, especially a tractor shovel as shown in FIG. It is located at the bottom center of 1. However, regardless of whether the shift control lever 4 that controls the transmission 3 is mechanical or electrical, the control lever 5 for operating the shovel is
It is established separately.

<Problems to be Solved by the Invention> However, in the conventional case described above, when the vehicle is advanced toward the earth and sand, the vehicle is operated in second gear until just before hitting the earth and sand.
In order to obtain a large thrusting force immediately before thrusting, the shovel operating control lever 5 must be operated at the same time as switching the vehicle from second gear to first gear. Furthermore, when going backwards, it was necessary to switch from first gear to second gear. However, this work was complicated and required skill.

The present invention has been made to solve the above-mentioned drawbacks, and it is possible to change the vehicle speed when moving forward while operating the shovel operation control lever, and it is also possible to change the vehicle speed when moving backward after scooping up dirt. To provide a device which can simplify driving operation by only turning on a reverse switch.

<Means for Solving the Problems> In the means for solving the problems according to the present invention, manual switching of the transmission that controls the vehicle speed is performed by connecting and connecting a plurality of fluid pressure clutches, and a plurality of A tractor shovel equipped with electrically operated valves is provided with a group of speed change switches that control the supply of electricity to each of the electrically operated valves. speed) When the switch is in operation, a speed other than the lowest speed (e.g. 2nd speed)
The power to the electrically operated valve is cut off and the lowest speed gear (first gear) is set.
A selector switch for energizing the electrically operated valve is attached to the grip of the control lever for operating the shovel.

In addition, when the reverse switch is turned on while the forward switch, the speed gear other than the lowest gear (for example, second gear) switch, and the changeover switch are in operation, the power to the electrically operated valve for the lowest gear (first gear) is cut off. An interlocking means (for example, an interlocking switch) is provided for switching the forward switch and the reverse switch so as to energize the electrically operated valve for the speed stage (for example, second gear).

<Operation> In the above problem solving means, when the forward switch is turned on to connect the forward clutch and the second speed switch is turned on to connect the second speed clutch,
The vehicle rushes into the dirt in second forward gear. At that time, when the changeover switch is pressed while operating the grip of the shovel operating control lever, the vehicle speed is switched from second gear to first gear by the action of the interlocking means that interlocks with the forward switch.

Next, when the vehicle is to be moved backwards after scooping up the earth and sand, the reverse clutch is engaged by switching to the reverse switch, and the forward switch and interlocking means work to return the vehicle speed to second gear.

<Example> Below, the present invention will be explained based on the example shown in FIGS. In a tractor shovel that is provided with a plurality of solenoid valves 6 that individually operate pressure clutches, a group of speed change switches 7 that control energization to each of the solenoid valves 6 is provided, and a forward switch of this switch group is provided. A changeover switch 9 is attached to the grip part 10 of the control lever 5 for shovel operation, which cuts off the power to the second speed solenoid valve 20 and energizes the first speed solenoid valve 19 when the second speed switch 8 and the second speed switch 8 are closed. When the reverse switch 11 is turned on with the forward switch 12, second speed switch 8, and selector switch 9 closed, the first speed solenoid valve 19 is de-energized and the second speed solenoid valve 2 is turned off.
an interlocking switch 12a that switches the forward switch 12 and the reverse switch 11 so as to energize the forward switch 12 and reverse switch 11;
is provided. In addition, the interlocking switch 12a
The forward switch 12 and the reverse switch 1
1 is interlocked with both switches 12 and 11 by an interlocking mechanism A whose opening and closing are reversed.

In this embodiment, the conventional transmission 3
The shift control lever 4 for controlling the gear shift control lever 4 is replaced by a shift switch group 7.

In the figure, 13 is a one-speed switch, 14 is a three-speed switch, and 15 is a four-speed switch. Further, 16 is a relay, and 17 and 18 are an A contact and a B contact of the relay 16, respectively.

Furthermore, when the reverse switch 11 is turned on with the forward switch 12, second speed switch 18, and selector switch 9 closed, the interlock switch 12a
This is for automatically switching from first gear to second gear.

Next, to explain the operation, when the forward switch 12 is turned on to connect the forward clutch and the second speed switch 8 is turned on to connect the second speed clutch, the vehicle will move toward the earth and sand in the second forward speed. enter abruptly. At that time, while operating the grip part 10 of the control lever 5 for shovel operation, press the push button 9a of the push button type changeover switch 9 to turn on the switch 9. Since the interlocking switch 12a that interlocks with the forward switch 12 has already been turned on, the relay 16 is energized, its B contact 18 opens and the second-speed solenoid valve 20
Since the A contact 17 closes at the same time, the first gear solenoid valve 19 is energized and the vehicle speed is switched from second gear to first gear. Next, when scooping up dirt and reversing the vehicle, switch to the reverse switch 11 to connect the reverse clutch, and the interlocking mechanism A
forward switch 12 and interlocking switch 12a via
opens, the circuit of relay 16 is cut off, and A contact 17
opens, and the B contact 18 closes to return to second gear again.

<Effects of the Invention> As is clear from the above description, according to the present invention, when the vehicle enters dirt in second forward gear, the changeover switch attached to the handle of the cargo handling control lever automatically switches the vehicle from second forward gear to sand. It is possible to switch to first forward speed, and when scooping up dirt, simply turning on the reverse switch causes the interlocking means (in this example, the interlocking switch) to work, automatically switching the vehicle to second reverse speed. This has the excellent effect of being able to quickly control the gear shift to the required speed stage with a simple operation.

[Brief explanation of drawings]

FIG. 1 is an electric circuit diagram showing a quick transmission during operation according to an embodiment of the present invention, FIG. 2 is a sectional view showing a changeover switch according to an embodiment of the present invention, and FIG. 3 is a diagram showing a conventional transmission. It is a side view of a tractor shovel. 5: Control lever for shovel operation, 6:
Solenoid valve, 7: Gear change switch group, 8: Second speed switch, 9: Changeover switch, 10: Grip, 11: Reverse switch, 12: Forward switch, 12a: Interlocking switch, 13: First speed switch, A: Interlocking mechanism,
16: Relay.

Claims (1)

[Claims] 1. In a tractor shovel in which manual switching of a transmission for controlling vehicle speed is performed by connecting and connecting a plurality of hydraulic clutches, and a plurality of electrically operated valves are provided that individually operate each hydraulic clutch, each of the electrically operated valves A group of speed change switches is provided to control the energization of the valves, and when the forward switch and the speed gear switch other than the lowest gear in the switch group are in operation, the power to the electrically operated valve for the speed gear other than the lowest gear is cut off. A changeover switch is attached to the grip of the control lever for shovel operation, and the reverse switch is connected to the operating state of the forward switch, the switch for speeds other than the lowest speed, and the selector switch. A tractor shovel characterized in that interlocking means is provided for switching the forward switch and the reverse switch so that, when turned on, the electrically operated valve for the lowest gear is cut off and the electrically operated valve for the gears other than the lowest gear is energized. - Quick transmission when working.