JP4297878B2 - Combine height cutting device - Google Patents

Description

  The present invention relates to a cutting height detection device used for automatic cutting height control in a combine, and in particular, it is vertically moved around a front fulcrum at a lower portion of a cutting portion connected to a front portion of a traveling machine body so as to be movable up and down. The present invention relates to a cutting height detecting device in which a grounding body that swings and follows the grounding is provided and the swinging of the grounding body is detected by an angle sensor.

  The grounding body used in the cutting height detection device swings up and down around the front fulcrum, so if you move backward with the cutting part lowered to the working height, the grounding body will bite into the ground and be damaged. Or, there is a risk of significant deformation.

Therefore, as a means for solving such a problem, as disclosed in Patent Document 1, a sensor unit composed of a grounding body and a sensor box is supported so that it can be retracted upward, or only the grounding body is supported. As shown in Patent Document 2, the grounding body is made of a leaf spring material that is curved downwardly to form a convex curve in the middle in the longitudinal direction. A configuration has been proposed in which the top portion is grounded and the rear end portion of the grounding body is guided and locked to the cutting portion so as to be movable back and forth at a position above the ground.
Japanese Utility Model Publication No. 58-152837 (FIGS. 2, 6, and 7) JP 2004-283008 A

  In the cutting height detection device disclosed in Patent Document 1, it is possible to reliably avoid the grounding body from biting into the ground by retracting the entire sensor unit or the grounding body upward during reverse travel. However, an operation mechanism for retracting and moving the sensor unit or the grounding body is required, and the structure becomes complicated and the operation becomes troublesome.

  Further, in the cutting height detection device disclosed in Patent Document 2, since the convex top of the curved grounding body made of a leaf spring material is grounded, it can be moved forward or backward without performing a special retraction operation. However, the grounding body does not bite into the ground and is excellent in durability and handleability, but in order to prevent undue external force from acting on the grounding body during reverse travel, It is necessary to give a loose angle of attack that is the same as the forward angle of attack to the rear extension part from the top of the curve. Therefore, the total length of the grounding body becomes considerably long, and the cutting height detector is installed in the front-rear direction. The space was long. In addition, since the rear end of the grounding body is locked and supported by the cutting part, when foreign matter such as weeds or straw scraps enters the grounding body, it is caught by the locking part at the rear end of the grounding body. There was also a risk of accumulation.

  The present invention has been made paying attention to such points, and it is a main object of the present invention to enable a relatively compact arrangement of a cutting height detection device capable of avoiding damage and deformation during reverse travel. It is said.

1st invention detects the rocking | fluctuation of the grounding body which rocks | fluctuates up and down centering | focusing on a front fulcrum and follows a grounding in the lower part of the cutting part connected to the front part of the traveling body so that raising and lowering is possible. Deploying a detection case that supports an angle sensor, extending the grounding body backward and downward, and configured to swing following the ground using the rear end as a grounding point,
The detection case is installed at a position rearward from the front fulcrum and is supported so that it can be retracted and rotated in the forward upward direction around the rear fulcrum, and the grounding external force acting on the rear end of the grounding body during the forward movement is detected. The case acts to rotate the case around the rear fulcrum in the forward and downward direction, and the grounding external force acting on the rear end of the grounding body during reverse rotation causes the detection case to rotate about the rear fulcrum in the forward upward direction. It is comprised so that it may act.

  According to the above configuration, when the cutting portion is moved to the cutting height, the ground reaction force acting on the rear end portion of the grounding body works to rotate the detection case in the forward downward direction, and the detection case has a predetermined detection posture. Maintained. That is, since there is no possibility that the detection case is retracted upward by the ground reaction force acting on the grounding body, it is unnecessary to hold the detection case particularly strongly in the detection posture.

  If the rear end of the grounding body is grounded and moved backward, an external force acts forward on the rear end of the grounding body, and this external force causes the detection case to retreat and pivot in the upward direction around the rear fulcrum. Thus, the front fulcrum of the grounding body is retreated and moved upward. Accordingly, the grounding body is in an upright posture with the rear end in contact with the ground, and the grounding body slides and moves on the ground as the aircraft moves backward while maintaining this posture.

  In addition, when switching from reverse to forward, a rearward external force acts on the rear end of the grounding body in the standing posture, and the detection case rotates in the forward downward direction and returns to the original detection posture again. To do.

  In addition, since the rear end portion of the grounding body follows the grounding, the space above the grounding body is opened to the rear, and even if the ground contaminants get entangled with the grounding body as it moves forward, It slips backward and does not get entangled with the grounding body.

  Therefore, according to the first aspect of the present invention, the grounding body and the angle sensor can be automatically retracted and rotated upward using the ground reaction force without requiring any special operation during reverse travel, thereby avoiding damage or deformation. A cutting height detection device having excellent durability can be configured.

  In addition, the detection case does not retreat upward due to the ground reaction force acting on the rear end of the grounding body during normal mowing, so there is no need to hold the detection case in a detection posture with a strong return spring. When a forward force is applied to the rear end of the grounding body as it moves backward, the grounding body can be retracted and rotated upward, and the grounding body can be retracted and maintained without applying a large external force. It will be a thing.

  Moreover, by using the grounding body in the rearwardly lowered posture, impurities on the ground do not adhere to and accumulate on the grounding body at the time of forward movement, and the grounding body can be shortened in the front and rear directions to be compactly configured.

According to a second invention, in the first invention,
The length of the grounding body is set so that the rear end portion of the grounding body is grounded behind the rear fulcrum in the cutting height detection state during forward movement.

  According to the above configuration, the detection case is stably held in a predetermined detection posture by applying the turning force in the forward and downward direction by the ground reaction force acting on the grounding body not only in the forward detection state but also in the travel stop state. Therefore, the first invention can be suitably implemented.

According to a third invention, in the second invention,
When the grounding body swings to the lower limit with respect to the detection case, the rear end portion of the grounding body is set to be positioned substantially directly below the rear fulcrum.

  According to the above configuration, the grounding body that swings to the lower limit as the mowing part rises when the mowing part is lifted again after the mowing part has been greatly lifted in a state where the traveling is stopped is caused by the lowering of the mowing part. Grounding from the end and swinging upward around the front fulcrum, the rear end of the grounding body that has started swinging upward around the front fulcrum immediately moves backward from the rear fulcrum of the detection case. Thus, even when the cutting part is lowered from the high position to the working height region in the traveling stop state, the detection case does not rotate forward from the detection posture by the ground reaction force from the grounding body, and the second The above-described effect of the present invention is promoted.

A fourth invention is the invention according to any one of the first to third inventions,
A contact restricting means for restricting the rotation limit of the detection case in the forward and downward direction is provided, and a return spring for rotating and energizing the detection case in the forward and downward direction is provided.

  According to the above configuration, when switching from backward to forward, the detection case that has been retracted and rotated in the forward upward direction is rotated and returned to the detection posture that is the rotational limit in the forward and downward direction. In this case, even if the rotation resistance at the rear fulcrum of the detection case is large, the detection case is urged and rotated in the forward downward direction by the return spring, and is quickly returned to the detection posture. Therefore, when moving forward, the lifting control based on the detection of the appropriate cutting height can be performed without delay.

A fifth invention is the fourth invention, wherein:
The return spring is built in the detection case.

  According to the above configuration, it is possible to prevent mud and foreign matter from adhering to the return spring, and to accurately perform the return rotation of the detection case, and it is possible to suitably implement the fourth invention.

  FIG. 1 shows a side view of the self-removing combine. This combine is connected to a front part of a traveling machine body 2 provided with left and right crawler traveling devices 1 so as to be able to move up and down with a four-row cutting specification, and to the traveling machine body 2, a driving unit 4, a threshing device 5, and The grain collection tank 6 and the like are mounted.

  The mowing unit 3 includes four pulling devices 7 for raising a plurality of planted cereals to a cutting posture, a clipper-type mowing device 8 for cutting the stock of the raised cereals, and a plurality of mowing cereals. It is equipped with a feeding and conveying device 10, etc., which is fed to the starting end of the feed chain 9 equipped in the threshing device 5 and delivered in a laid down posture. The base end of the trimming part frame 11 is supported by a base 12 erected on the front part of the traveling machine body 2 so as to be able to swing up and down around the lateral fulcrum P. The mowing unit 3 is driven up and down by the expansion and contraction operation of the hydraulic cylinder 13 mounted across the part frame 11.

  The hydraulic cylinder 13 is controlled and operated by an electromagnetic valve (not shown). This electromagnetic valve is automatically controlled based on detection information from a cutting height detection device A provided at the lower front end of the cutting unit 3 (automatic cutting (automatic cutting). (Height control) and switching operation is also performed by an artificial command provided by operating the operation lever 14 provided in the operation unit 4 back and forth.

  As is well known, the automatic cutting height control is to raise and lower the cutting unit 3 by operating a control valve so as to maintain the ground height (cutting height) of the cutting unit 3 at a set value. In the invention, the cutting height detection device A used for the automatic cutting height control is configured as follows.

  As shown in FIG. 2, at the lower end of the mowing portion 3, a weeding frame 15 that is one more than the number of raised lines (in this case, five) is arranged in parallel in a forward cantilever shape with a predetermined left and right spacing. The lower end of the device 7 is connected and supported by being raised at the front end of the weeding frame 15, and the weeding tool 18 is bolted to the support rod 16 inserted into and connected to the weeding frame 15 so as to be adjustable and detachable. ing. Then, a cutting height detection device A is provided below each of the second support rods 16 from the left and right outer ends, for example, based on the average value of the cutting heights obtained by the left and right cutting height detection devices A Automatic cutting height control is performed.

  As shown in FIG. 3, this cutting height detection device A detects the height of the cutting unit 3 with respect to the ground (farm scene) in a grounded manner, is bent in a mountain shape, and has a vertical plate shape at the front end of the support rod 16. A bracket 17 is provided, and the weeding tool 18 is bolted to the vertical plate-shaped bracket 17 so that the position of the weeding tool 18 is adjustable and detachable, and a cutting height detection device A is mounted.

  The cutting height detection device A basically includes a sensor bracket 21 connected to and supported by the vertical plate-shaped bracket 17, a detection case 22 attached to a side surface of the sensor bracket 21, and a laterally facing front portion of the detection case 22. The grounding body 23 is supported so as to be able to swing up and down around the front fulcrum X, and an angle sensor 24 using a rotary potentiometer attached to the side surface of the detection case 22.

  The sensor bracket 21 is formed by bending a thick plate material into a bowl shape in plan view, and a rolling support shaft 25 protruding from the front end thereof is fixed to the rear end portion of the vertical plate bracket 17. The entire cutting height detection device A is rotatably supported around the rolling fulcrum R by being inserted into and connected to the boss portion 26. As shown in FIGS. 6 and 7, a torsion spring 27 is externally fitted to the boss portion 26, and both free end portions 27 a and 27 b project rearward from the support rod 16 and are fixed spring receiving pins 28. Is pinched with a predetermined initial elastic force from the left and right, and a pin 29 protruding from the upper front end of the sensor bracket 21 is held between the free end portions 27 a and 27 b of the torsion spring 27.

  Accordingly, the torsion spring 27 held in a fixed posture via the fixed spring receiving pin 28 sandwiches the pin 29 from the left and right, so that the sensor bracket 21 that is rotatable around the rolling fulcrum R has the grounding body 23 directly below. It is elastically held in a predetermined neutral position located at. When a greater turning force than set is applied to the sensor bracket 21 from the outside, the sensor bracket 21 is rotated while the one of the free end portions 27a and 27b of the torsion spring 27 is pushed and deformed by the pin 29, and the external force is eliminated. The sensor bracket 21 is returned to its original posture by a torsion spring 27. Therefore, even if a large external force acts on the grounding body 23 sideways, such as when the body is steered while the grounding body 23 is grounded, the cutting height detection device A as a whole rotates in a rolling manner. Damage to the detection device A is avoided beforehand.

  A bearing bush 30 and an oil seal 31 are incorporated in the boss portion 26 so that the cutting height detection device A can be smoothly rotated and removed and attached to the boss portion 26. The rolling fulcrum portion is waterproofed by using a rubber washer for the washer 39 of the set screw 38. Further, a guide rib 32 protrudes from one side portion of the vertical plate bracket 17 so as to extend rearward, and obliquely rearward from the other side portion of the vertical plate bracket 17 to near the outside of the front portion of the sensor bracket 21. A guide member 33 made of a leaf spring material is provided in a cantilever manner, and guides such as weeds and straw scraps that approach the rotation fulcrum of the sensor bracket 21 as the vehicle travels forward are guided by the guide rib 32 and the guide member 33. It is configured to escape left and right.

  A fixed support shaft 35 protrudes laterally from the rear portion of the sensor bracket 21, and the detection case 22 is rotatably mounted around the rear support point Y on the fixed support shaft 35. The detection case 22 has a left and right divided structure, and an inner part described later is incorporated in a state in which one of the divided cases 22a is inserted into the fixed support shaft 35 and is prevented from coming off by the stopper ring 34, and then the divided case 22a is assembled. The other split case 22b is joined to the case 22a and screwed together. A needle bearing 36 and an oil seal 37 are incorporated between the fixed support shaft 35 and the detection case 22 to reduce the rotational resistance of the detection case 22.

  A fulcrum shaft 41 is horizontally supported at the front portion of the detection case 22, and the grounding body 23 is connected to the protruding end of the fulcrum shaft 41. As shown in FIG. 11, the grounding body 23 is composed of a strip-shaped main portion 23 a having a suitable width and a front portion that is tapered, and a longitudinal plate that is bent and connected to one side of the front portion. The connecting base portion 23b is detachably bolted to the projecting end portion of the fulcrum shaft 41. The main portion 23a of the grounding body 23 extends rearward and downward at a position immediately below the extension line of the rolling fulcrum R, and the curved rear end portion 23c is more than the rear fulcrum Y of the detection case 22. The length of the main part 23a is set so as to be grounded at the rear. The front fulcrum portion of the grounding body 23 is surrounded by the front end portion of the sensor bracket 21 and the bent piece 21a that is bent and extended toward the rear, and is a contaminant that approaches from the front as the vehicle travels forward. Is prevented from getting around the front fulcrum X.

  The angle sensor 24 is screwed to the side surface of the detection case 22, and its sensor shaft 24a is inserted into the case. The fulcrum shaft 41 provided at the front portion of the detection case 22 is provided with a large diameter gear 42, and a small diameter gear 43 that meshes with the large diameter gear 42 is connected to the sensor shaft 24a. When the fulcrum shaft 41 is rotated by the vertical swing of the body 23, it is amplified and transmitted to the sensor shaft 24a, and a small vertical movement of the grounding body 23 is detected by the angle sensor 24 as a large angle change. Yes.

  A spring 45 is stretched over the large-diameter gear 42 and the spring receiving pin 44 in the case, and the fulcrum shaft 41 is urged to rotate so that the grounding body 23 is urged to swing downward. The body 23 smoothly swings up and down following the change in the height of the ground. Here, the end portions 42a and 42b in the circumferential direction of the large-diameter gear 42 are in contact with the raised portions 46a and 46b in the case, so that the swing limits of the fulcrum shaft 41 and the grounding body 23 are restricted. .

  3, when the grounding body 23 swings to the lower limit with respect to the detection case 22, the rear end portion 23c of the grounding body 23 is positioned substantially directly below the rear fulcrum Y. It is set to be. Accordingly, when the cutting unit 3 is greatly lifted and lowered again after traveling is stopped, the grounding body 23 that has swung to the lower limit as the cutting unit 3 is lifted is lowered by the lowering of the cutting unit 3. After grounding from the rear end portion 23 c, it swings upward around the front fulcrum X, but the rear end portion 23 c of the grounding body 23 that starts swinging upward around the front fulcrum X immediately becomes the rear portion of the detection case 22. Move backward from the fulcrum Y.

  A flange 47 is attached to the inner end portion of the fixed support shaft 35 that rotatably supports the detection case 22 so as to be integrally rotatable, and spans between the flange 47 and a spring receiving pin 48 in the case. The return spring 49 is stretched, and the detection case 22 is lightly rotated and biased around the rear fulcrum Y in the forward downward direction. In addition, a stopper 50 is protruded laterally at the front portion of the outer side surface of the detection case 22, and the stopper 50 contacts the upper end edge of the sensor bracket 21, thereby limiting the forward downward rotation limit of the detection case 22. It is regulated in contact.

  The cutting height detection device A according to the present invention is configured as described above. When the cutting unit 3 is at the cutting work height and is moving forward, as shown in FIG. The rear end portion 23c is biased to ground behind the rear fulcrum Y of the detection case 22, and the ground reaction force acting on the rear end portion 23c works to rotate the detection case 22 in the forward downward direction. 22 is stably held at a detection position that is a predetermined forward-lowering rotation limit due to its own weight, tension of the return spring 44, grounding reaction force from the grounding body 23, drag resistance accompanying grounding sliding of the grounding body 23, and the like. In this state, the grounding body 23 swings up and down in response to a change in the height of the ground, and the swing is detected by the angle sensor 24.

  When the backward movement is performed without raising the mowing unit 3, an external force acting forward is applied to the rear end portion 23c of the grounding body 23, and acts as a rotational force in the upward direction on the detection case 22. In this case, the detection case 22 will rotate upward when it receives its own weight and a turning force in the forward and upward direction that is larger than the turning force in the forward and downward direction by the return spring 49, as shown in FIG. As described above, the detection case 22 rotates upwardly about the rear fulcrum Y. As a result, the front fulcrum X of the grounding body 23 is retracted upward, and the main part of the cutting height detection device A is swung up to the retracted position in the space below the bent support rod 16.

  Further, as shown in FIG. 10, the step 51 formed in the vicinity of the rear fulcrum Y inside the detection case 22 contacts the step 47a of the flange 47 in the fixed state, so that the detection case 22 When the swing-up rotation limit is restricted and the detection case 22 is rotated backward to the swing-up rotation limit, the grounding body 23 that swings to the biased swing limit is lower than the lower end of the vertical plate-shaped bracket 17. It is designed to retreat upward.

  Further, when switching to the forward movement, the detection case 22 at the retracted position rotates downward and automatically returns to the original detection position so that the cutting height can be detected. In this case, the return spring 49 is provided so as to be surely returned to the front-down position even when the rotational resistance at the rear fulcrum Y increases, and is a spring for biasing the grounding body 23 to ground. What is weaker than 45 is used.

  The angle sensor 24 is covered with a resin protective cover 52 attached to the outside thereof, and a harness 53 led out from the rear end of the angle sensor 24 is integrally formed inside the protective cover 52. After being guided by the locking and guided toward the inside of the machine body, it is led backward. When the detection case 22 is in the normal detection position, the harness lead-out position d of the protective cover 52 is above the rear fulcrum Y of the detection case 22, and when the detection case 22 is swung up to the retracted position, the protective cover is provided. The angle sensor 24 is attached in advance to the detection case 22 so that the harness lead-out position d of 52 is below the rear fulcrum Y of the detection case 22. As a result, even if the detection case 22 rotates greatly, the movement of the harness 53 in the front-rear direction is reduced, and the harness 53 is not unduly twisted or pulled, thereby preventing a disconnection accident.

  [Other Examples]

  (1) As shown in FIG. 12 or FIG. 13, a cutting height detection device A may be provided in the cutting unit 3 having the 5-row cutting specification or the 6-cut cutting specification.

  (2) The return spring 44 may be located on the rear fulcrum Y and may be configured by a torsion spring built in the detection case 22.

  (3) In the above embodiment, the return spring 49 for urging the detection case 22 in the forward downward rotation direction is provided to make the return rotation of the detection case 22 in the forward downward direction more reliable. If the material or thickness of the detection case 22 is appropriately selected to increase the weight of the entire case and increase the rotational force in the forward and downward direction due to its own weight, the return spring 49 is weaker. . Further, the return spring 49 can be omitted if a sufficient rotational force in the forward and downward direction due to its own weight can be secured.

Combine side view Schematic plan view of the cutting part Left side view of cutting height detection device Plan view of cutting height detector Right side view of cutting height detection device Longitudinal side view of main part of cutting height detection device Front view showing rolling structure of cutting height detection device Cross-sectional plan view of cutting height detector Left side view of cutting height detection device in reverse Longitudinal side view in the detection case swing-up state Top view of grounding body Schematic plan view of the cutting part showing an example of arrangement of the cutting height detection device in the 5-cutting specification Schematic plan view of the cutting part showing an arrangement example of the cutting height detection device in the 6-cutting specification

Explanation of symbols

2 traveling machine body 3 cutting part 22 detection case 23 grounding body 23c rear end part 24 angle sensor 49 return spring X front fulcrum Y rear fulcrum

Claims (5)

A grounding body that swings up and down around the front fulcrum and follows the ground and an angle sensor that detects the swinging of the grounding body are supported at the lower part of the cutting part that is connected to the front part of the traveling machine body so as to be movable up and down. Deploying a detection case, extending the grounding body backward and downward, and configured to swing following the ground using the rear end as a grounding point,
The detection case is installed at a position rearward from the front fulcrum and is supported so that it can be retracted and rotated in the forward upward direction around the rear fulcrum, and the grounding external force acting on the rear end of the grounding body during the forward movement is detected. The case acts to rotate the case around the rear fulcrum in the forward and downward direction, and the grounding external force acting on the rear end of the grounding body during reverse rotation causes the detection case to rotate about the rear fulcrum in the forward upward direction. A combine cutting height detecting device characterized in that it is configured to act as described above.   2. The cutting height detection of the combine according to claim 1, wherein the length of the grounding body is set so that the rear end portion of the grounding body is grounded behind the rear fulcrum in a state where the cutting height is detected during forward movement. apparatus.   The combine cutting height according to claim 2, wherein when the grounding body swings to a lower limit with respect to the detection case, the rear end portion of the grounding body is positioned substantially directly below the rear fulcrum. Detection device.   The contact restriction means for restricting the rotation limit of the detection case in the forward downward direction is provided, and a return spring is provided for rotating and energizing the detection case in the forward downward direction. The combined cutting height detection device according to the item.   The combine cutting height detection device according to claim 4, wherein the return spring is built in the detection case.

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