JPS6123297Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an elevating device for an attached working machine in a tractor, and more specifically, an elevating working machine is provided on the abdomen of the tractor, and a Bowden wire is provided for raising and lowering it. For those configured with a hydraulic lift arm, a lifting link, and a swinging link to respond to the wire, the relationship between the lifting link and the swinging link is particularly important to minimize the force required to raise the work equipment at the lifting end. This is intended to prevent excessive tensile load from being applied to the Bowden wire, thereby increasing the life of the wire.

As is well known, a tractor is equipped with an elevating type working machine such as a mower through its abdomen, and a Bowden wire is constructed as a means for raising and lowering the mower as appropriate. This method has been adopted because it has more precise operability and superior durability than the conventional type, which uses a pulley to change direction and transmit lifting force.

In this case, the general method is to connect another lifting lift to the hydraulic lift arm, connect another swinging link to this link, and connect the inner Bowden wire to one end of the swinging link. In this case, the mower that is lifted via these links will hit the stopper at the lifting limit and be held stably by the tractor, and this lifting force will be obtained by the same wire. be.

However, currently, the angle between the lifting link and the swinging link at the lifting limit is quite small, and therefore the rotational force of the swinging link is excessive beyond that necessary to lift the work equipment. Due to the heat, the wires may be stretched abnormally due to the fact that the work equipment is in a fixed position, and in severe cases, the wires may break, so it was hoped that an effective solution would be provided. .

This idea was devised in consideration of these circumstances, and the features here are that the work equipment is mounted on the underbelly of the tractor so that it can be raised and lowered freely, and the swing link is pivoted midway at the rear of the tractor. One end of this swing link and the work machine side are connected by a tension member, and the other end of the swing link and the lift arm of the hydraulic system are connected by a lifting link, and the work machine is lifted by lifting the lift arm. In a lifting device for an attached work implement of a tractor that can be lifted up to an upper limit position close to the lower abdomen of the tractor, the mounting position of the swing link is such that when the work implement is lifted to an approximately upper limit position, the swing link pivots. The point is that the fulcrum, the connection point between the swing link and the lifting link, and the connection point between the lifting link and the lift arm are set in a substantially straight posture.

This invention will be explained below with reference to an example shown in the figure. The figure shows an example of a so-called mid-mount type agricultural tractor T equipped with a rotary mower M on the lower abdomen thereof.

First, to explain the outline of More M, 1
2 is a mower body, 2 is a cutter, and 3 is an input box. The mower body 1 can be freely controlled to an appropriate height by gauge wheels 4, 4 and a lift operation lever 5 arranged at the front and rear of the mower body 1. The cutter 2 can be freely driven by connecting a power take-off box 6 vertically installed from the front end of the engine to the input box 3 through a universal joint 7.

In this case, the cutter is driven by a vertical cutter main shaft 30 having an integral pulley 31 at the upper outer surface thereof as shown in FIG.
A cutter 2 with a disc spring 32 is fastened to the lower end of the cutter 2, so that a certain amount of impact can be absorbed by the slip of the disc spring 32.

In order to vertically raise and lower the mower M, the second
As shown in FIG.
A pair of these is placed on each of the left and right sides. 9 is a gate-shaped upper link that connects two legs and one end thereof with a rod, and 10 is a lower link that connects the front and rear ends of the rod and the mower body 1, and the lifting guide link 11 consisting of these is a By arranging them on the left and right, a pantograph type guide mechanism is constructed.

In this case, if the upper link 9 is made integral, even if you try to pin one leg when attaching it to both stays 8, the other leg will also face the same direction, making the attachment very troublesome. Therefore, the upper link 9 may be separated from the front and back, and the lower link 10 may be integrated, as shown in the fourth illustrated example. In this case upper link 9
Each of the legs is individually pivoted, so when one is attached, the other will hang down, allowing for independent and effortless attachment.

In this way, a bracket 12 is attached to each stay 8 on the rear side.
is protruded from the bowden wire W (tensile member).
Fix the outer a, and the inner b
As shown in the figure, a fixed cylinder 13 protruding from the rod of the upper link 9 is provided with a rotary cylinder 14, and the terminal is connected to this, or as shown in the fourth figure, it is connected to the legs of the lower link 10. The upper limit of the rise of the mower M by the link is determined by stoppers 33, 33 protruding from the bottom of each stay 8.

On the other hand, in order to respond to the Bowden wire W, a lift arm 16 with a hydraulic device 15 is provided at the rear of the tractor T, and this can be freely raised and lowered, and each pair of arms 16 is provided with a lifting link 1 shown in FIG.
7 is pivotally connected, and the lower end of the lifting link 17 is pivotally connected to one end of a swinging link 18 formed in a dogleg shape.

The swing link 18 has a lift arm 16 in the middle.
The pivot brackets 16 have pivot points in the same direction as the tractor, and these pivot brackets 16 are provided on opposite sides of the rear end of the tractor. As a result, the actuator moves upward from the state shown by the imaginary line in FIG.

In addition, in order to transmit the operation of the swing link 18 to the mower M, an L-shaped outer receiving metal fitting 22 is fixed on both sides of the front part of the pivot bracket 19, and an outer a of the Bowden wire W is attached to this metal fitting 22. The inner b is pivotally connected to the lower end of the swing link 18. These are configured as a pair on the left and right, and in particular, the lifting link 17 and the swinging link 18 form an angle of approximately a right angle at the lower limit, but at the upper limit where the mower M is stopped and locked by the stopper 33, the lifting link 17 and the swing link 18 form a right angle at the lower limit. The angle α made as shown in the solid line in Figure 6 is approximately
The force is large, around 150 degrees, and therefore the component force for rotating the swing link 18 is very small.
It is said that the minimum force required to lift and hold the mower M can be generated.

That is, when the mower M almost reaches the upper limit position where it is locked, the pivot point of the swing link 18, the connection point between the swing link 18 and the lifting link 17, and the connection between the lifting link 17 and the lift arm 16. The mounting position of the swing link 18 is set such that the point is substantially straight as shown by the solid line in FIG. 6, and after the mower M reaches the upper limit position, the lift arm 1
6, the upward force on the swinging link 18 is large, the torque for swinging becomes extremely small, and the tensile force exerted on the Bowden wire W by the swinging link 18 does not become excessive. It is something.

This invention is as described above, and the swing link, which transmits the lift of the lift arm of the hydraulic system through the lifting link and lifts the work machine through the tension member, lifts the work machine to approximately the upper limit position. Sometimes, the mounting position is set so that the pivot point of the swing link, the connection point between the swing link and the lifting link, and the connection point between the lifting link and the lift arm are in a substantially straight line. After the machine has risen to approximately the upper limit position, the swinging force of the swinging link becomes extremely small, and the tensile force on the tension member becomes small, preventing accidents such as breakage due to excessive tension as much as possible, and reducing the lifting force of the lift arm. It can be absorbed at the pivot point of the dynamic link.

In addition, the link of the lifting link 17 includes a link such as a chain or a wire,
Furthermore, the scope of work equipment includes mid-mount type and other types of work equipment other than mowers.

[Brief explanation of the drawing]

Figure 1 is a side view of a mid-mounted tractor with a mower showing an example of this invention, Figure 2 is its front view, Figure 3 is a perspective view of the lifting guide link mechanism, and Figure 4 is a side view of a tractor with a mid-mount mower.
Figure 5 is a perspective view showing an improved link mechanism, Figure 5 is an enlarged sectional view showing the structure of the cutter attachment part with a disc spring, Figure 6 is a side view of the Bowden wire response mechanism,
FIG. 7 is a rear view thereof. T... Tractor, M... Mower, W... Bowden wire, 15... Hydraulic system, 16... Lift arm, 17... Lifting link, 18... Swinging link.

Claims (1)

[Scope of Claim for Utility Model Registration] A working machine is equipped on the underbelly of the tractor so that it can be raised and lowered freely, and the swing link is pivoted midway at the rear of the tractor.
One end of this swing link and the work machine side are connected by a tension member, and the other end of the swing link and the lift arm of the hydraulic system are connected by a lifting link, so that when the lift arm rises, the work machine is lowered. In a lifting device for an attached working machine of a tractor that can be lifted up to an upper limit position close to the abdomen, the mounting position of the swing link is such that when the work equipment is lifted to a substantially upper limit position, the pivot point of the swing link and the swing A lifting device for an attached working machine in a tractor, characterized in that a connection point between a dynamic link and a lifting link and a connection point between a lifting link and a lift arm are set in a substantially straight posture.