JPH0440964B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a lifting device for a working machine in a riding vehicle such as a tractor.

[Prior art]

In general, in a passenger working vehicle such as a tractor, the raising and lowering of agricultural or construction ground working equipment is actually carried out by hydraulic cylinders mounted on the front and rear of the vehicle body.

By the way, the selection operation of the front and rear hydraulic cylinders for operating the agricultural or construction ground work equipment in such conventional riding work vehicles is selectively performed by operating a switching lever provided on the hydraulic control device. Furthermore, the lifting and lowering operations of both of these hydraulic cylinders, that is, the lifting and lowering operations of various ground work machines, were also performed by a lifting lever that was provided separately from the switching lever.

That is, a conventional hydraulic control device for operating a land-based work machine for agriculture or construction in a passenger work vehicle has a switching lever for selecting the front and rear hydraulic cylinders, and a lifting member on the side of the selected hydraulic cylinder. It was equipped with two levers, one for raising and lowering. To operate such a lifting device, either the front or rear lifting member is selected using a switching lever, and after this selection, the lifting lever is used to move the lifting member up and down.

[Problem that the invention seeks to solve]

However, in the conventional device, when switching the elevating member back and forth, it is necessary to operate both the switching lever and the elevating lever. That is, when switching to the other elevating member after operating either the front or rear elevating member, first operate the elevating lever to the neutral position to bring the operating elevating member to the neutral state, and then, It is necessary to operate the switching lever to select the other elevating member. Therefore, in the past, there was a problem that lever operation was complicated and troublesome.

The present invention has been made in consideration of the above circumstances, and includes a lever operation when switching between the front and rear elevating members,
In particular, it is an object of the present invention to provide a lifting device for a work machine that can simplify lever operation when switching from a rear lifting member to a front lifting member.

[Means and actions for solving problems]

In order to achieve the above object, the present invention includes an elevating member for elevating and lowering a working machine from the front and rear of a passenger working vehicle such as a tractor, a single hydraulic control device for selectively operating the elevating members for the front and rear parts, and a hydraulic control device for selectively operating the elevating members for the front and rear parts. a switching lever for switching the operation of the lifting member at the front; a lifting lever for raising and lowering the lifting member selected by the switching lever; and a switching lever that connects the switching lever and the lifting lever, and the switching lever selects the lifting member at the front. The device is characterized by being equipped with a return member that returns the elevator lever to the neutral position when the lift lever is moved.

In the above configuration, when the front elevating member is selected by operating the switching lever, the return member automatically returns the elevating lever to the neutral position, so there is no need to operate the elevating lever at the time of switching.

Further, in the present invention, the switching lever and the rear elevation member are connected by a feedback rod, the elevation lever is provided with a cam member, and when the switching lever selects the rear elevation member, the It engages with the cam member to interlock the rear elevating member and the elevating lever, and when the switching lever selects the front elevating member, it separates from the cam member and releases the interlock between the rear elevating member and the elevating lever. The present invention is characterized in that an adjuster is provided on the feedback rod.

With this configuration, when the rear elevating member is selected by operating the switching lever, the rear elevating member and the elevating lever are connected and the elevating lever operates the rear elevating member. When the elevating member at the rear is selected, the elevating member at the rear is disconnected from the elevating lever, and the elevating member at the rear becomes inactive.

〔Example〕

First, an overview of a riding vehicle (tractor) equipped with a lifting device for a working machine according to the present invention will be explained with reference to FIG.

The drawing is a partially cutaway side view of the riding vehicle 1. The engine is mounted on the front part of the vehicle body 2 of the riding vehicle 1, and the transmission case is mounted on the rear of the vehicle body 2. It is located. The crankshaft of the engine and the transmission input shaft of the transmission case are connected substantially in a straight line via a propulsion shaft. Further, a passenger seat 3 is provided above the rear of the vehicle body 2, and front wheels 4 and rear wheels 5 are attached to the front, rear, left and right sides of the vehicle body 2, and the front and rear wheels 4, 5 can be steered by operating a handle 6. And four-wheel drive is now available.

Further, a lift device 7 is pivotally attached to the front and rear of the vehicle body 2 so as to be able to swing up and down, and a working machine (not shown in the figure) for, for example, agricultural or construction purposes is attached to the tip of this lift device 7. It is becoming more and more popular. One end of a link arm 9 of a link device 8 is pivotally connected to the lift device 7, and the other link arm 9 of the link device 9 is pivotally connected to a hydraulic cylinder 10. Further, each link arm 9 swings up and down due to the movement of the piston within the hydraulic cylinder 10.
It is designed to raise and lower the work equipment. Further, an oil tank 11 is installed in front of the rear hydraulic cylinder 10 and below the passenger seat 3. Hydraulic oil is supplied from this oil tank 11 to an oil pump, and the oil discharged from the oil pump is adjusted to the hydraulic pressure. The oil is selectively supplied to the front and rear hydraulic cylinders 10, 10 via a control device 13.

2 and 3 show the configuration of the main parts of the present invention, and in these figures, 10 is the rear hydraulic cylinder 10 (front hydraulic cylinder 10) described above.
(omitted), and 13 is a hydraulic control device.

A lifting lever 14 for raising and lowering the hydraulic cylinder 10 is provided on the left side in front of the hydraulic control device 13, and a switching lever 15 for switching between the front and rear hydraulic cylinders 10, 10 is provided on the right side. It is.

The elevator lever 14 is provided with an interlocking cam 17 that makes the rotating shaft 16 coaxial.
A spring 19 is stretched between the small arm 18 and the small arm 18 provided on the side of the switching lever 15. This spring 19 is connected to the switching lever 1 as described later.
When the link arm 5 selects the front link arm, it acts as a return member that returns the lift lever 14 to the neutral position.

A rod insertion portion 20 is provided in the center of the switching lever 15, and the tip of a feedback rod 21, one end of which is engaged with a rear link arm 9 operated by a hydraulic cylinder 10, is inserted into the rod insertion portion 20. The part is inserted.

In addition, the lift lever 1 of the feedback rod 21
4, a movable adjuster star 22 is attached, and when the switching lever 15 is operated to select the position shown by the solid line in FIG. 2, that is, the rear hydraulic cylinder 10, the feedback rod 21 is It comes into contact with the interlocking cam 17 when moving from the imaginary line position to the solid line position in the figure.

The operation will be explained below. First, when the switching lever 15 of the front/rear hydraulic cylinder 10 is in the rear position, the rear link arm 9 is in the raised position by operating the lift lever 14. At this time, when the link arm 9 of the hydraulic cylinder 10 descends, the feedback rod 21, one end of which is locked to the link arm 9, moves to the right in the figure. At this time, the movable adjuster star 22 attached to the feedback rod 21 comes into contact with the upper end of the interlocking cam 17 that rotates together with the lift lever 14, thereby rotating the lift lever 14 from the raised position to the neutral position. do.

Therefore, even if the rear link arm 9 naturally descends, the lift lever 14 will not remain in the raised/lowered position, and the rear link arm 9
It is possible to always return to the neutral position in conjunction with the operation of.

On the other hand, when the switching lever 15 is in the forward position in order to select the front link arm, the rod insertion part 20 provided on the switching lever 15 moves upward, so the feedback rod 21 is shown by a virtual line. move upwards. Therefore, the movable adjuster star 22 attached to the feedback rod 21
and an interlocking cam 1 that rotates together with the lifting lever 14.
7 will not separate from each other and come into contact with each other. Therefore, when the switching lever 15 is operated forward, the restraining force caused by the contact between the movable adjuster star 22 and the interlocking cam 17 is released. Therefore, the spring force of the spring 19 acts, and the small arm 18 that rotates together with the switching lever 15 and the interlocking cam 17 connected by the spring 19 are attracted toward the switching lever 15, so that the lifting lever 14 is always in the neutral position. automatically returns to position. In this embodiment, when the switching lever 15 for selecting the front link arm is operated, the spring 19 automatically returns the lifting lever 14 to the neutral position.
There is no need to operate the lift lever 14 to the neutral position when switching back and forth, simplifying lever operation and improving operability. Also, when the front link arm is selected, the contact between the movable adjuster star 22 and the interlocking cam 17 is released, so the feedback rod 21 to which the movable adjuster star 22 is attached
becomes a free state. For this reason, the rear link arm 9 connected to the feedback rod 21
is in a free state, so even if the lift lever 14 is operated, the rear link arm 9 will be in an inactive state and will not malfunction.

〔Effect of the invention〕

In the present invention, when the switching lever selects the front directional member, the lifting lever automatically returns to the neutral position, which eliminates the need to operate the lifting lever when switching the switching lever, simplifying the operation, and Improves sex. Further, when the switching lever selects the front lifting member, the linkage between the lifting lever and the rear lifting member is released, thereby eliminating malfunction of the rear lifting member.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an outline of a riding work vehicle equipped with a lifting device for a working machine according to the present invention, and FIGS. 2 and 3 are explanatory diagrams showing the main parts of the present invention. 9...Link arm, 10...Hydraulic cylinder, 1
3...Hydraulic control device, 14...Elevating lever,
15...Switching lever, 17...Interlocking cam, 18...Small cam, 19...Spring, 21...Feedback rod, 22...Movable adjuster star.

Claims (1)

[Scope of Claims] 1. A lifting member for raising and lowering a working machine to the front and rear of a riding vehicle such as a tractor, a hydraulic control device that selectively operates the front and rear lifting members, and a front and rear lifting member. a switching lever for switching the operation of the switching lever; a lifting lever for raising and lowering the lifting member selected by the switching lever; the switching lever and the lifting lever are connected, and when the switching lever selects the front lifting member; A lifting device for a work machine, comprising a return member for returning a lifting lever to a neutral position. 2. The switching lever and the rear elevation member are connected by a feedback rod, and the elevation lever is provided with a cam member, and when the switching lever selects the rear elevation member, the switching lever engages with the cam member. When the switching lever selects the front elevating member, the adjuster moves away from the cam member and disengages the rear elevating member and the elevating lever. An elevating device for a working machine according to claim 1, which is provided on a backroad.