JPS5930650Y2 - Agricultural tractor work equipment mounting device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a work equipment mounting device for an agricultural tractor, particularly one having a draft control device. In general, a draft control device for an agricultural tractor includes:
A rotatable link bracket that supports the top link is provided at the rear of the hydraulic lift, etc., and this link bracket is connected to a sensor spring for load detection, and an appropriate link is also provided between the link bracket and the hydraulic control unit. A mechanism is provided to connect them to each other, and when the working resistance in the soil acting on the top link becomes greater than the spring pressure of this sensor spring, the link bracket rotates while compressing this sensor spring, and the link bracket rotates while compressing this sensor spring. When the work equipment is pulled up, a force in the opposite direction is applied to the top link due to the weight of the work equipment, and at the same time, the sensor spring stretches and lowers the work equipment again. It is configured to allow

However, such draft control devices are not necessarily strong enough, and if a hydraulic top link with a hydraulic device or a special three-point link mechanism using a relatively long special bracket is installed,
When the work equipment is pulled up, the distance from the point where the work equipment's own weight is applied to the rotational fulcrum of the link bracket is long, so the moment becomes extremely large, and therefore the connection between the link bracket and the sensor spring is subjected to a large amount of force. A large amount of force will be applied and the part will be damaged.

Therefore, conventionally, when installing such a link mechanism, it is necessary to work without using a draft control device, but in order to do so, the draft control device section must be removed and replaced. , it was extremely troublesome.

In order to solve this problem, conventionally,
No. 50518, there is a device in which a stopper is used to connect the link bracket and the fixed bracket to stop the swinging of the link bracket when the draft control is not in use.

However, in such a conventional structure, if a strong force is applied to the fixed bracket, there is a risk that the fuselage part such as the mission case to which the fixed bracket is attached may be damaged.

In view of these points, the present invention has developed a link bracket stopper structure that is less likely to damage the rear case to which the fixed bracket is attached even if a strong force is applied to the fixed bracket as described above. The purpose is to provide.

In order to achieve this purpose, the configuration of the present invention is such that a link bracket rotatably mounted around a fulcrum axis is interlocked with a load detection sensor, and the work resistance transmitted through the top link is adjusted to the set pressure of this sensor. When the sensor is compressed and the work equipment is pulled up, the construction of the work equipment on the tractor is such that the link bracket is provided with a link bracket stopper, and the link bracket is fixed to the rear case of the tractor with bolts. A fixing bracket is provided, and the stopper is removably fixed to the fixing bracket, thereby preventing rotation of the link bracket. A constriction part is formed near the bolt closest to the fixing part to concentrate the stress of the bending moment on the bolt supporting part when a bending moment is applied to the fixing bracket via the stopper. be.

The structure of the present invention will be explained based on drawings showing one embodiment. Fig. 1 shows the entire tractor to which a rotary work machine is attached via a standard three-point linkage mechanism, 1 is a clutch housing, 2 is a clutch housing, and 2 is a clutch housing. , a transmission case connected to the rear part of the clutch housing 1, and this transmission case 2 is located at the rearmost part of the tractor body and constitutes the rear case of the present invention.

That is, in this embodiment, the rear case of the present invention refers to the transmission case 2.

3 is a hydraulic case placed on the upper part of the transmission case 2; 4 is a lift arm attached to the hydraulic case 3;
The rotary work machine 5 has a three-point linkage mechanism consisting of one top link 6 and two lower links 7.7.
It is attached to the rear of the mission case 2, and the lift arm 4
The lower link 7 is rotated via a lift rod 8 connected between the lower link 7 and the lower link 7, thereby raising and lowering the working machine 5. A rotary 11 is configured to be driven by a transmission shaft 10 connected to the shaft 9 via a universal joint.

FIG. 2 shows the structure of the draft control device with such a configuration. In the figure, 12 is a sensor rod fitted into the rear part of the hydraulic case 3 so as to be movable in the vertical direction. Spring holder 1
A sensor spring 15 is provided between the hydraulic case 3 and the top wall 14 of the hydraulic case 3.

16 is an adjustment nut screwed onto the upper end of the sensor rod 12 in order to regulate the amount of downward movement of the sensor spring 15 and the spring receiver 13; It shows the regulation plate installed in the middle.

On the other hand, a top link 6 is attached to the rear extension part of the hydraulic case 3.
A link bracket 20 having two connecting holes 18 and 19 on the upper and lower sides is rotatably mounted on a fulcrum shaft 21, and a sensor arm 22 extending forward from this link bracket 20 is connected to the spring. It is connected to the spring receiver 13 by a cylindrical shaft 23 welded to the holder 13 and a rotating shaft 24 inserted into the cylindrical shaft 23.

Similarly, this link bracket 20 is connected to a hydraulic control section (not shown) of the hydraulic case 3 via an appropriate link mechanism 2.5, and when the link bracket 20 is rotated clockwise in the figure, this link The hydraulic control unit is actuated via the mechanism 25, and the working machine 5 is lifted up by the lift arm 4.

The top link connecting holes 18 and 19 are selected and used as appropriate depending on the working machine, and the working resistance in the soil transmitted through the top link 6 is transmitted to the sensor through the link bracket 20. The spring 15 is installed in a selected position that compresses the spring 15, such as the lower connecting hole 19 in the case of a plow and the upper connecting hole 18 in the case of a rotary car.

Next, as shown in FIG. 4, 26 in FIG. These are two link bracket stoppers having a mounting hole 28 and a top link connecting hole 29 that fit into the connecting holes 19, 19, respectively, and a fixing hole 30 bored at the lower end of the forward inclined shape. , mounting hole 2 above
7.2B and bolts 31 and 32 inserted into the connecting holes 18 and 19 of the link bracket 20 that match these bolts, and are integrally attached to the outside of the link bracket 20.

Furthermore, a connecting pin 34 for connecting a hydraulic top link 33 is inserted into the top link connecting hole 29 of the stopper 26 and the connecting hole 19 of the link bracket 20 that fits therewith.

35 is a locking pin inserted into one end of the connecting pin 34;
6 is a pull-out ring attached to one end of the locking pin 35.

37 is the upper and lower horizontal frames 38 and 39, and the left and right vertical frames 40.4
A fixing bracket assembled into a rectangular frame shape by 1 and 4, and a fixing piece 43.
3 are provided facing each other, and two upper and lower bolts 45 are attached to the fixing plates 44, 44 attached to the left and right sides of the back surface.
, 46 to the rear side wall of the mission case 2.

9 is a PTO protruding from the rear of the mission case 2.
The shaft 47 is a hood-shaped PTO guard that further surrounds the PTO shaft 9 and the PTO shaft safety cover 8 that surrounds the PTO shaft 9. The fixing bracket 37 is fixed together by tightening bolts 45 and 46, and the fixing bracket 37 is attached so as to surround the PTO guard 48.

Fixing pins 49 are removably inserted into the fixing holes 30, 30 at the lower end of the link bracket stopper 26 and the fixing holes 42, 42 at the upper part of the fixing bracket 37. The link bracket 20 is fixed to prevent rotation, and in this way a work machine mounting device is realized that does not use a draft control device.

50 is a locking pin inserted into one end of the fixing pin 49; 51
is a pull-out ring attached to one end of the locking pin 50.

Furthermore, as shown in FIG. 3, the vertical frames 40 and 41 of the fixing bracket 37 are formed in a two-stage shape with a wide upper part and a narrow lower part. Of the bolts 45 and 46 that fix the fixing bracket 37, the constricted part 54 is located near the bolt 45 closest to the fixing part of the stopper 26.
It is arranged slightly above the center line of the fixing bracket 37 to concentrate the stress of the bending moment acting on the fixing bracket 37 on this part.

The constricted portion 54 in this case may have an acute angle shape.

What is shown in FIG. 4 above is the case where the hydraulic top link 33 is attached, and when the bracket 55 in the special three-point link mechanism is attached, the configuration is as shown in FIG. 6.

That is, as shown in this figure, the connecting pin 34 for the hydraulic top link is removed, and the two left and right brackets 55, 55 are connected to the link bracket 20 and the stopper 2.
Attachment holes 56, 57 interposed between the link bracket 20 and the stopper 26, and at the attachment holes 27, 28 between the link bracket 20 and the stopper 26,
It is fixed by inserting the bolts 31 and 32 mentioned above.

In the above, the bracket 55 for the special three-point link mechanism
It is also possible to install the hydraulic top link 33 with the bracket 55 and connecting pin 34 still attached, and if you want to install a standard three-point link mechanism with the bracket 55 and connecting pin 34 still attached, you can attach the fixed pin If the link bracket 49 is removed, the link bracket 20 can be freely rotated, so that the draft control device can be used as is.

The present invention has the above-mentioned configuration.In this way, in the present invention, a fixing bracket is provided on the rear case of the tractor, which is fixed with a bolt, and the stopper provided on the link bracket can be freely attached to and removed from the fixing bracket. Because it is configured to be fixed to the top, there is no need to remove the final draft control device even when installing a hydraulic top link or a special 3-point link mechanism, and it can be used in combination with the installation of a standard 3-point link mechanism. It is possible.

Moreover, in the present invention, a constriction is formed in the fixing bracket near the bolt that is closest to the fixing part of the stopper, so that the stress of the bending moment acting on the fixing bracket is concentrated on the bolt part. Because of this structure, when a huge bending moment due to the weight of the work equipment is applied to the fixed bracket when the work equipment is raised, and exceeds the allowable limit of the rear case, the fixed bracket will bend at this constriction. This bending moment is generated by the bending of the fixing bracket and the slight elongation of the bolt, thereby preventing damage to the rear case.

[Brief explanation of the drawing]

Figure 1 is an overall view of the tractor, Figure 2 is a vertical sectional view of the draft control device, Figure 3 is a vertical sectional view showing how the device of the present invention is installed, Figure 4 is a front view of the link bracket stopper, and Figure 4 is a front view of the link bracket stopper. 5 and 6 are rear views of the tractor showing the installed state of the device of the present invention. 2...Mission case, 5...Rotary work machine, 6...Top link, 15...
...sensor spring, 20... link bracket, 21... fulcrum shaft, 26...
Link bracket stopper, 33... Hydraulic top link, 37... Fixed bracket, 45
, 46... Bolt, 54... Constriction.

Claims (1)

[Scope of utility model registration request] A link bracket that is rotatably mounted around a fulcrum axis is interlocked and connected to a load detection sensor, and when the work resistance transmitted through the top link becomes greater than the sensor's set pressure, the sensor is compressed and the work equipment is pulled up. In order to attach the work equipment to the tractor, a link bracket stopper is provided on the link bracket, and a fixing bracket fixed with a bolt is provided on the rear case of the tractor, and the stopper is attached to this fixing bracket. The fixing bracket is configured to be removably fixed and thereby prevent rotation of the link bracket, and the fixing bracket has a bolt that is connected to the stopper in the vicinity of the bolt that is closest to the fixing part of the stopper of the bottle. A working equipment mounting device for an agricultural tractor, characterized in that a constriction is formed to concentrate stress of the bending moment on the bolt support portion when a bending moment is applied to the fixing bracket.