JPH0767327B2 - Working machine-mounted traveling vehicle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a traveling vehicle equipped with a working machine such as a tractor.

(Prior Art) For example, in a tractor, a working machine such as a rotary cultivator, a harvester, or a lifting machine is mounted at a rear portion thereof via a working machine lifting hydraulic apparatus and a three-point link mechanism in a vertically movable manner.

The hydraulic device is operated by pressure oil from a hydraulic pump, and the pressure oil is controlled by hydraulic pressure control means, and position control or draft control is performed.

Further, the engine that generates the traveling driving force of the tractor drives the hydraulic pump, and the rotational speed is adjusted by the speed control mechanism.

(Problems to be Solved by the Invention) In field work with a tractor-equipped work machine, it is necessary to quickly raise the work machine when turning the tractor on the shore.
Although the work implement is raised by the hydraulic device, the engine rotation speed is lowered during turning, so that the amount of oil to the hydraulic device is reduced, and the work implement raising speed may be slowed down.

The decrease in engine speed is also due to the heavy weight of the work equipment, but it is often artificial and the driver may reflexively loosen the accelerator during turning even when working at low speeds. This is because.

The present invention, in conjunction with the work machine raising operation by the hydraulic device,
It is an object of the present invention to provide a working machine-mounted traveling vehicle in which the problems of the above-mentioned conventional techniques can be solved by operating the speed control mechanism toward the engine speed increasing side.

(Means for Solving the Problem) A specific configuration for solving the problem in the present invention includes an engine 2 that generates a traveling driving force, a speed adjusting mechanism 20 that adjusts the rotation speed of the engine 2, and an engine 2. A working machine mounting type traveling vehicle having a driven hydraulic pump 15 and a working machine lifting hydraulic system 12 equipped with a hydraulic control means 41 and operated by pressure oil supplied from the hydraulic pump 15. 12 is a sensor S that detects a work implement raising operation.
The speed control mechanism 20 is provided with an actuator B for operating the speed control mechanism 20 to the engine speed increasing side by a signal from the sensor S when the engine 2 is lower than a predetermined rotation speed.

(Operation) When the operating lever 42 of the hydraulic control means 41 is turned to the work machine rising side, the sensor S detects this and actuates the actuator B. When the actuator B is operated, the accelerator rod 17 is moved, and the engine 2 is operated by the speed adjusting mechanism 20 toward the speed increasing side.

When the rotation speed of the engine 2 is increased, the rotation speed of the hydraulic pump 15 is increased, the amount of oil supplied to the hydraulic device 12 is increased, and the decrease in the rising speed of the work machine 38 is prevented.

(Example) Hereinafter, the Example of this invention is described based on drawing.

1 to 6, reference numeral 1 denotes a tractor, which directly connects an engine 2, a clutch housing 3 and a mission case 4 to form a traveling vehicle body 5. A main clutch 6 is built in the clutch housing 3 and a clutch housing 3 and a mission are provided. A transmission 7 is built in the case 4, and is configured so that the traveling driving force generated by the engine 2 is transmitted to the transmission 7 via the main clutch 6 to drive the drive wheels 8.

Steps 10 are provided on the left and right side portions of the traveling vehicle body 5, a pair of fenders 11 are attached to the rear side portions thereof, a working machine lifting hydraulic device 12 is mounted on the rear upper portion thereof, and above the hydraulic device 12. Has a driver's seat 13.

An injection pump 14 is provided at the right front part of the engine 2, and a hydraulic pump 15 is provided in the vicinity thereof, and the hydraulic pump 15 is transmitted with power from a crankshaft of the engine 2. Reference numeral 16 denotes a speed control lever provided on the injection pump 14, to which the front end of the accelerator rod 17 is connected.

Reference numeral 20 denotes a speed control mechanism, which includes an accelerator pedal 21 and a pedal arm 22, which are pivotally supported by the right step 10, a transmission shaft 23, arms 24 and 25,
It is composed of a connecting rod 26, a hand accelerator lever (not shown), the accelerator rod 17 and a speed adjusting lever 16, etc. By depressing the accelerator pedal 21, the accelerator rod 17 is moved in the direction of arrow A to adjust the speed. lever
16 can be swung to the acceleration side.

In the hydraulic device 12, a cylinder 27 is arranged in a cylinder case 28, a piston rod 30 abuts a piston 29 arranged in this cylinder, and an arm 32 fixed to an arm shaft 31 penetrating the cylinder case 28 in the lateral direction. On piston rod 30
Are pin-connected. Lift arms 33 are fixed to both ends of the arm shaft 31.

A top link 36 and left and right lower links 37 forming a three-point link mechanism 35 are connected to the rear part of the traveling vehicle body 5, and a working machine 38 such as a rotary cultivator, a harvester and a lift device is connected to the rear ends of these. The lift arm 33 is connected to the lower link 37 via a lift rod 39, and the hydraulic device 12
The work machine 38 can be raised and lowered by the operation of.

The hydraulic device 12 is provided with hydraulic control means 41 in a circuit for supplying pressure oil from the hydraulic pump 15 to the cylinder 27. The hydraulic control means 41 has a control valve (not shown) attached to the cylinder case 28, a position control lever (operation lever) 42 for operating the control valve, a draft control lever 43, and the like.

The hydraulic control means 41 includes a position control lever
A rotation sensor S1 for detecting the rotation of the work machine in the ascending direction is provided, and the detection signal of the rotation sensor S1 is sent to the actuator B of the speed governing mechanism 20 via the control box 44. A variable resistor, a rotary encoder, or the like can be used as the rotation sensor S1.

The actuator B is a linear actuator B1 that linearly moves the accelerator rod 17 by a certain amount as shown by the solid lines in FIGS. 2 and 3, or a transmission shaft 23 or an arm 24 that is rotated by a certain angle as shown by the dashed line in FIG. The rotary actuator B2 or the like is used to move the accelerator rod 17 in the direction of arrow A to increase the engine rotation speed by a certain amount.

That is, when the position control lever 42 is rotated to raise the work implement 38 at the time of turning the tractor or idling, even if the rotation speed of the engine 2 is, for example, 700 rpm, the actuator B1 is driven by the signal from the rotation sensor S1. Or, B2 operates to operate the speed control mechanism 20 to the engine speed increasing side, and the rotation speed of the engine 2 is, for example, 1000 to 1500 rpm.
Raise to. As a result, the discharge amount of the hydraulic pump 15 increases, and the hydraulic device 12 can raise the work implement 38 at a relatively high speed.

The rotation sensor S1 detects the rotation only when the position control lever 42 is rotated in the ascending direction, and does not detect it when it is rotated in the descending direction. Therefore, when the working machine 38 descends, the speed of the engine 2 is increased. Is not done. This is a hydraulic system 12
The same applies when a double-acting cylinder is used.

The time for operating the position control lever 42 is short, and there is a lime lag before the engine 2 speeds up and the amount of pressure oil to the hydraulic device 12 increases.
44 is provided with a timer or the like so that the actuator B is operated for a certain period of time after receiving a detection signal from the rotation sensor S1.

In FIGS. 1 and 5, S2 is a rotation detection sensor that detects the rotation speed of the arm shaft 31, and this rotation detection sensor S2 indicates the rotation speed of the detected arm shaft 31 in the comparator 45. When it is higher than the dynamic speed, the operation signal from the rotation sensor S1 to the actuator B is cut off, and the engine speed is increased only when the rotation speed of the arm shaft 31 is low.

The rotation sensor S1 for the position control lever 42
It is also possible to provide only the rotation detecting sensor S2 for the arm shaft 31 without providing the above, and operate the actuator B by this rotation detecting sensor S2. That is, the sensor S is the hydraulic device 12
It may be provided in addition to the hydraulic control means 41, and the operation of a moving member may be detected when the working machine 38 is raised.

In the case of the rotation sensor S1, not only the rotation of the position control lever 42 is detected, but also the rotation amount or the rotation speed can be calculated by the arithmetic processing by the calculator 46, and the rotation amount or the rotation speed is proportional to the rotation amount or the rotation speed. Actuator B is operated by means of the actuator B, and the rotational speed of engine 2 can be set higher when the rotational amount is large or the rotational speed is high.

In FIG. 1, 47 is a speed detector that detects the rotation speed of the engine 2, and is connected to the control box 44.
If the engine rotation speed is a constant speed suitable for raising the work implement, a signal for blocking the operation of the actuator B is issued.

That is, if the rotation speed of the engine 2 is 1000 rpm, for example,
The hydraulic pump 15 can raise the work implement 38 at a substantially appropriate speed, and when the tractor 1 is turned at this rotation speed, it is not necessary to increase the speed of the engine 2 and therefore the actuator B need not be operated.

If the upper limit of the engine speed increase by the actuator B is set to 1000 rpm, for example, the speed detector 47 can be omitted.

The present invention is not limited to the above embodiment, but can be variously modified. For example, an arc-shaped linear variable resistor that detects the operation of the control lever 42 or the lift arm 33 is used for the sensor S, or the actuator B is brought into contact with the bent portion of the arm 24, 25 or the rod 17, 26 to connect it. A solenoid that pushes in the engine acceleration direction may be used.

(Effect of the Invention) According to the present invention described in detail above, the hydraulic device 12 is provided with the sensor S for detecting the work machine raising operation, and the speed control mechanism 20 is provided with the sensor S when the engine 2 is lower than the predetermined rotation speed. Since the actuator B that operates the speed governing mechanism 20 to the engine speed increasing side by the signal from S is provided, even if the engine rotation speed is lowered during turning, idling, or when mounting a heavy work machine, When the work implement 38 is raised via the hydraulic device 12, the sensor S acts to actuate the actuator B of the speed governing mechanism 20 to increase the engine rotation speed to increase the rise speed of the work implement 38. Workability can be improved.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is an explanatory diagram, FIG. 2 is an exploded perspective view of a speed control mechanism, FIG. 3 is a sectional explanatory view of a linear actuator, and FIG. 4 is hydraulic control means. FIG. 5 is an exploded perspective view of the hydraulic apparatus main body, and FIG. 6 is a side view showing a tractor rear portion to which the present invention can be applied. 1 …… tractor (running vehicle), 2 …… engine, 12 ……
Hydraulic device, 15 …… hydraulic pump, 16 …… speed control lever,
20 …… speed control mechanism, 35 …… three-point link mechanism, 38 …… work machine, 41 …… hydraulic control means, 42 …… position control lever, 44 …… control box, S …… sensor, B ……
Actuator.

Claims (1)

[Claims] 1. An engine (2) for generating a driving force for traveling,
This speed control mechanism (2
0), a hydraulic pump (15) driven by the engine (2), and a hydraulic control means (41), which is operated by hydraulic oil supplied from the hydraulic pump (15) to elevate the working machine. (12) and a working machine-mounted traveling vehicle, wherein the hydraulic device (12) is provided with a sensor (S) for detecting a working machine lifting operation, and the speed control mechanism (20) is provided with an engine (2). When the engine speed is lower than a predetermined rotational speed, an actuator (B) for operating the speed governing mechanism (20) to the engine acceleration side by a signal from the sensor (S) is provided, and the working machine mounted traveling vehicle is provided. .