JPS6134776B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cutting height control device for a combine harvester in which a reaping pretreatment section that is driven up and down by a hydraulic cylinder is connected to the front of the vehicle body, and in particular, the control valve of the hydraulic cylinder is controlled by a ground sensor. Concerning improvements in mechanical operation.

In a conventional control device, a structure for linking a control valve with a ground sensor includes, for example, linking the control valve and a vertically swinging ground sensor with a release wire, and urging the control valve in the downward control direction with a spring. However, when the mowing height becomes lower and the ground sensor is displaced upward from the neutral position, this is transmitted to the control valve via the release wire, and the control valve is operated in the upward control direction against the spring. When the mowing height increases, the ground sensor is allowed to move downward, and the control valve is operated in the downward control direction by the spring.

In this case, if the ground sensor rides up forcefully on a stone or clod of soil that protrudes into the field, or if the ground sensor violently contacts the ground when crossing a ridge,
A thrusting force suddenly acts on the ground sensor, forcing the release wire to be pulled strongly, resulting in damage to the sensor itself and the release wire.

This invention aims to solve the above-mentioned problems by improving the linkage structure between the control valve and the ground sensor, and includes a ground sensor that is movable up and down and biased downward by a spring at the bottom of the pre-harvesting section. The control valve of the hydraulic cylinder is biased by a spring in the upward control direction, and the valve and the ground sensor are connected by a flexible mechanical linkage capable of transmitting only the downward displacement of the ground sensor to the control valve. When the control valve is operated in the upward control direction by the spring and the ground sensor is displaced downward from the neutral position by the flexibility of the link mechanism, the ground sensor is displaced downward from the neutral position. The present invention is characterized in that the control valve is operated in a downward control direction by a sensor biasing spring against the biasing spring.

In other words, in the present invention, contrary to the conventional method, when the cutting height becomes low and the ground sensor is displaced upward,
This sensor is released through the flexibility of the linkage mechanism with the control valve, so even if you suddenly climb onto a stone or clod of earth, or hit the ground when going over a ridge, the ground sensor can be easily moved upwards. This allows it to be used effectively for a long period of time with less damage.

Embodiments of the present invention will be described in detail below with reference to illustrative drawings.

As shown in FIGS. 1 and 2, the stems are introduced into a pair of left and right stalk introduction paths A ₁ and A 2 at the front of the vehicle body equipped with a crawler traveling device 1, a threshing device 2, a driver's seat ₃ , etc. A device 4 for pulling up a stem culm, a clipper-type cutting blade 5 for cutting the base of the pulled stem culm, auxiliary conveyance devices 6a, 6b for conveying the cut stem culm backwards and merging them together;
A reaping pre-processing section 8 consisting of a rear conveyance device 7 that conveys the merged stem culms toward the threshing device 2 is provided, and as the machine advances, the stem culms planted in the field are harvested and then threshed. It is structured so that the processing operations are performed automatically and continuously. Note that this combine harvester is normally set to perform circular mowing work with the already cut area located on the right side of the machine body.

The support frame 8a of the reaping pretreatment section 8 is pivotally supported to the vehicle body by a hydraulic cylinder 9 so as to be swingable around the horizontal axis X, and as shown in FIGS. 3 to 5, A horizontal shaft 10 is provided on the right side of the cutting blade 5 and supported by the frame 8a.
In contrast, the front ends of a pair of ground sensors 11, 11, which are larger than the plant diameter of the countermeasure stem culm and arranged side by side with a lateral interval smaller than the planting interval, are pivoted so as to be vertically swingable around the axis Y. and both the sensors 11, 11
Springs 12, 12 are provided for biasing each of them downward. Further, a wire 15 extending from the swing operating arm 14 of the control valve 13 that switches the operating state of the hydraulic cylinder 9 is vertically aligned with the tongue pieces 16 attached to both the sensors 11, 11, respectively. The elongated holes 17 and 17 allow for flexibility in relative movement in the vertical direction, and the pin 18 is used to connect the swing operating arm 14 to the spring 19.
At this point, the hydraulic cylinder 9 is extended and biased to perform a lifting operation to raise the reaping section. Both the sensors 11,1
When both of the heights of the cutting blades 1 are within the set range, or when one of the heights is within the set range and the other is rising above the set range, the control valve 13 is activated to stop the operation of the hydraulic cylinder 9. When the height of the mower blades of both sensors 11, 11 relative to the mower blades rises too far out of the set range, the control valve 13 operates to extend the hydraulic cylinder 9 to raise the reaping processing section. Furthermore, both the sensors 1
When the height of at least one of the mower blades of 1 and 11 falls outside the set range, the control valve 13
is configured to shorten the hydraulic cylinder 9 and switch to a state in which the reaping processing section is lowered,
In addition, the height of the cutting blade 5 relative to the ground is automatically maintained at a set height, thereby stabilizing the cutting height.

In short, the cutting height is stabilized regardless of pitching of the vehicle body by automatically raising and lowering the cutting processing section while detecting the height of the cutting blade 5 above the ground using both sensors 11, 11. In addition, even if one of the pair of sensors 11, 11 rides on a foreign object such as straw waste, uncut stem culms, or a stump and goes out of the setting range, the reaping processing section is prevented from rising, and the foreign object is removed. This is designed to prevent malfunctions due to this.

Further, a valve operating lever 21 is provided for locking and moving the swing operating arm 14, which is biased toward the lowering operation by the sensors 11, 11, toward the ascending operation using a locking pin 20; By switching this lever 21 to the raised position U, the raising/lowering stop position N, and the lowering position D, the reaping processing section can be arbitrarily raised and lowered, and furthermore, by switching this lever 21 to the automatic position A, the above-mentioned pin 20 to arm 14
The reaping processing section is moved to a position where it does not come into contact with the sensor 11, and the reaping processing section is automatically moved up and down based on the information from both the sensors 11, 11.

In order to provide both the sensors 11, 11, three weeding tools 22 located at the front ends of the paths _A4 , _A2 ...
A rod-shaped frame portion 8b along the front-rear direction that supports the rightmost one of …, and this frame portion 8
A reinforcing frame 24 is provided which connects a branching rod 23 that extends in a cantilevered manner surrounding both the sensors 11, 11 from the front end of the sensor b toward the rear, right, lateral, and outer side,
The supporting frame 2 of the horizontal shaft 10 is connected to the reinforcing frame 24.
5 are connected with bolts to prevent the uncut stem culms from falling into both sensors 11 and 11 using the grass dividing rod 23 during the middle splitting work when the uncut stem culms are located on both sides of the machine body. The reinforcing frame 24 is designed to guide the stem culm (see Fig. 5C), and the reinforcing frame 24 also serves as a sensor mounting frame.

[Brief explanation of the drawing]

The drawings show an embodiment of the cutting height control device for a combine harvester according to the present invention, and FIG. 1 is an overall plan view of the combine, FIG. 2 is a side view of the front part of the combine, and FIG. 3 is a diagram showing the combination of a ground sensor and a control valve. Connection diagram, Figure 4 is a partially cutaway plan view of the ground sensor mounting part, Figure 5 A,
B and C are schematic front views of the same part. 8 ... Reaping pre-processing section, 9... Hydraulic cylinder, 1
DESCRIPTION OF SYMBOLS 1... Grounding sensor, 12... Spring for sensor grounding bias, 13... Control valve, 19... Spring for biasing control valve.

Claims (1)

[Scope of Claims] 1. A cutting height control device for a combine in which a reaping pre-processing section 8 which is driven up and down by a hydraulic cylinder 9 is connected to the front part of the vehicle body, and a cutting height control device is provided at the lower part of the reaping pre-processing section 8 . A ground sensor 11 that is movable and urged downward by a spring 12 is provided, and the hydraulic cylinder 9
The control valve 13 is biased in the upward control direction by a spring 19, and the valve 13 and the ground sensor 11 are connected to each other by a flexible mechanical system capable of transmitting only the downward displacement of the ground sensor 11 to the control valve 13. When the ground sensor 11 is displaced upward from the neutral position, the control valve 13 is operated in the upward control direction by the spring 19 due to the flexibility of the link mechanism, and the ground sensor 11 is moved to the neutral position. A cutting height control device for a combine harvester, characterized in that when the sensor biasing spring 12 moves further downward, the control valve 13 is operated in a downward control direction against the biasing spring 19. 2. The cutting height control device according to claim 1, wherein the control valve 13 and the ground sensor 11 are linked by a release wire 15.