JPH11146717A - Cutting height control device in combine - Google Patents

Abstract

(57) [Problem] To eliminate the instability of the detection result by the ultrasonic sensor 20, when the height of the ground is detected by the ultrasonic sensor 20 to control the elevation of the cutting pre-processing device. SOLUTION: A support bracket 107 is screwed onto a screw shaft 104 which is provided substantially vertically on the back side of a grain stalk raising device 6 in a pre-cutting device 4, and an ultrasonic sensor 20 is operated by operating a control motor 105. When it is determined that the target cutting height set value set by the cutting height setting device is larger than the reference value stored in the control device 70 in advance, the ultrasonic sensor 20 is moved to the lower position sensor 109. Down to the position
Change control is performed so as to shorten the distance between the ultrasonic sensor 20 and the ground 103.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a harvesting pre-processing device which is mounted on the front of a traveling body of a combine so as to be able to move up and down, and a detection signal of a non-contact type cutting height sensor and a target cutting height by a cutting height setting device. The present invention relates to a technology for automatically adjusting a cutting height from a field scene by controlling a cutting pre-processing device to raise and lower the cutting height position so that the cutting height position follows the target cutting height set value. Things.

[0002]

2. Description of the Related Art Conventionally, as a cutting height sensor device for this type of combine, Japanese Patent Laid-Open Publication No. Hei 6-300833 discloses an ultrasonic non-contact cutting height sensor device. Generally, in a reflection type ultrasonic sensor, the time from the time when an ultrasonic wave emitted from a transmitter (transmitter) is reflected by a detection target (ground) to the time when the ultrasonic wave is received by a receiver (receiver) is received. It is determined that the longer the length, the longer the distance from the reflection type ultrasonic sensor to the detected portion (ground), that is, the higher the cutting height.

[0003]

However, when the height (distance) from the reflection type ultrasonic sensor to the ground is large, the energy of the emitted ultrasonic wave is absorbed (absorbed) by the sound propagation medium (air). ) The rate of attenuation increases, and the energy of the detection signal detected by the receiver tends to decrease.
Especially when used for harvesting and threshing by combine
Because the emitted ultrasonic waves are liable to be irregularly reflected due to such as straw waste in the field scene or unevenness of the soil surface of the field, the energy of the detection signal detected by the receiver tends to be low, and therefore,
If the height from the ultrasonic sensor to the ground (distance proportional to the cutting height) is too large, the detection signal value (normal voltage value)
And the instability of the detection result increases.

Therefore, if the installation height of the ultrasonic sensor mounted on the pre-cutting device is large, the detection signal tends to be unstable, that is, it is determined that the cutting height is high based on the detection signal value. However, in practice, it is easy to cause an error such as that the height from the mowing part to the ground is too low, and the lower end of the mowing pre-processing device is easily sunk into the ground,
There was a problem that the equipment was damaged and the soil was carried into the threshing unit together with the harvested culm.

Accordingly, an object of the present invention is to provide a cutting height control device in a combine which improves the stability of the detection result by a non-contact sensor device in order to solve the above-mentioned problem.

[0006]

According to a first aspect of the present invention, there is provided a cutting height control device for a combine according to the present invention. The raising / lowering drive means is configured to be able to move up and down, and to compare a detection signal of a non-contact cutting height sensor for detecting a ground height of the pre-cutting device with a target cutting height set value by a cutting height setter. A cutting height control device for a combine harvester configured to actuate a cutting height sensor provided for raising and lowering an arrangement height of the non-contact type cutting height sensor; When the set value is set higher than the reference value, a control means is provided for controlling the movement of the arrangement height of the non-contact type cutting height sensor in a lower direction by the sensor elevating means.

[0007] The invention described in claim 2 is the first invention.
In the cutting height control device in the combine described in the above,
The control means includes: storage means for storing the reference value; calculation means for calculating an operation amount for operating the sensor elevating means in accordance with the stored reference value; and And a correcting means for correcting the value of the detection signal from the non-contact cutting height sensor in accordance with the height change amount obtained by changing the arrangement position height.

According to a third aspect of the present invention, in the cutting height control apparatus for a combine according to the first or second aspect, the non-contact type cutting height sensor is constituted by a reflection type ultrasonic sensor. The sensor elevating means includes attitude correcting means for correcting the direction of emission and reception of ultrasonic waves so as to be substantially perpendicular to the ground. The cutting height control device in the combine according to the fourth aspect of the present invention is configured such that the cutting pre-processing device can be moved up and down with respect to the front part of the traveling machine body by a lifting drive means, and Height control device in a combine which is configured to operate the lifting / lowering drive means by comparing a detection signal of a non-contact type cutting height sensor for detecting the height with a target cutting height set value by a cutting height setter. In the case where the target cutting height set value by the cutting height setter is set higher than the reference value, even if it is determined that the cutting height detection value by the detection signal is higher than the target cutting height set value, A control means configured to execute control for prohibiting the lowering control of the mowing pre-processing device is provided.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described. FIG. 1 is a side view of a traveling body 1 of a combine having a pair of right and left traveling devices 2 provided with traveling crawlers 2a. FIG. 2 is a front view of the traveling body, FIG. 3 is a plan view of the traveling body 1, FIG. 4 is a side view of an elevation position sensor for detecting a position at which the pre-cutting device and the traveling aircraft are moved up and down, and FIG. Front view of the elevation position sensor,
FIG. 6 is a skeleton diagram of power transmission, FIG. 6 is a functional block diagram of a hydraulic circuit and a control device, and FIG. 8 is a side view of lifting / lowering means of the ultrasonic sensor.

As shown in FIGS. 1 to 3, a threshing device 3 having a conventionally known configuration is mounted on the left side in the traveling direction of the traveling body 1, and a single-acting type is mounted on the front of the traveling body 1. A cutting pretreatment device 4 that can be moved up and down by a hydraulic cylinder 9 is arranged. A clipper-type cutting blade device 5 is disposed below the lower frame of the pre-cutting device 4, and a grain stem raising device 6 for six rows is disposed in front of the clipping blade device 5. A grain culm conveying device 8 is disposed between the feed chain 7 and the front end of the feed chain 7 for supplying the grain culm, and six rows of weeds 10 protrude from the lower front of the grain stalk raising device 6. A driver's cab 11 is arranged at the front right side of the traveling machine body 1, and a grain tank 12 is arranged at the rear side. In the cereal stalk conveying device 8, the stalk root caused by the cereal stalk raising device 6 is conveyed while being pinched, and the root of the cereal stem is inherited by the front end of the feed chain 7.

As shown in FIG. 4 and FIG. 5, the base end of a front downwardly inclined lifting / lowering cylinder frame 14 having a front end attached to the mowing pretreatment device 4 is fixed to a horizontal cylinder 15, and the horizontal cylinder 15 is mounted on a traveling machine body. 1 is rotatably supported by a plurality of bearing brackets 16 (one of which is not shown) provided at a front portion of the vehicle body 1 and receives power from an engine 35 on the traveling machine body 1 in each of the horizontal cylinder 15 and the lifting cylinder frame 14. Transmission shafts 17 and 19 arranged in the inner diameter portion,
Power is transmitted to each part of the pre-cutting device 4 via the bevel gear pair 18 and the like. The lifting pre-processing device 8 is driven up and down by a lifting hydraulic cylinder 9 (see FIG. 1) mounted between the middle part of the lifting cylinder frame 14 and the traveling machine body 1.

As shown in a skeleton diagram (FIG. 6) showing the power transmission system of the combine, one of the outputs from the engine 35 is transmitted to a bottom conveyor 37 and a vertical conveyor 38 in the grain tank 12 via a clutch 36. And then to a screw conveyor (not shown) in the discharge auger 28. The other output from the engine 35 is transmitted via the power branching mission 39 to the handling cylinder drive shaft 40 and the sorting drive shaft 4.
1. A hydraulic pump for traveling The power is transmitted to a drive shaft 43 to a hydraulic motor type (HST type) traveling drive unit 42 and to a constant speed rotation drive shaft 44 to a pre-cutting device 4. The other output from the engine 35 turns ON / OFF the power transmission via the threshing clutch 48a in the power branching mission 39, and the handling cylinder 13 via the handling cylinder drive shaft 40 or the sorting drive shaft 41. And the processing cylinder 29, the first gutter screw conveyor 26 a, Karan Juan, the second gutter screw conveyor 26 b and the second reduction conveyor 25, the straw chain 31,
It is transmitted to the suction fan 30 and the straw cutter 33.

On the other hand, the cutting shaft 47 output from the (HST type) traveling drive unit 42 via a one-way clutch 45a (which can be transmitted only during forward rotation of the traveling drive unit) and a tuning clutch 46 through a cutting clutch 47. Power to
It is transmitted directly to the feed chain 7. The power transmission to the pre-cutting device 4 is turned ON / OFF via a cutting clutch 49 provided on the cutting shaft 47. In order to turn on / off the threshing clutch 48a, the tuning clutch 46, the inflow clutch 48, and the reaping clutch 49, respectively, a clutch actuator such as an electromagnetic solenoid corresponding to each clutch is turned on / off. . The tuning clutch 46 may be a tension clutch that cuts off the power by tensioning and relaxing the tension of the belt. Therefore, as described later, when the vehicle speed tuning control is prohibited (stopped) or the like, power is transmitted to the reaping shaft 47 via the constant-speed rotation drive shaft 44 of the power branching mission 39, and the HST traveling drive unit 42 The one-way clutch 45a idles when the output rotation speed of the cutting synchronization drive shaft 45 is lower than the rotation speed from the constant speed rotation drive shaft 44 or when the cutting synchronization drive shaft 45 rotates in the retreating direction of the combine. .

The HST type (in which a mechanical transmission mechanism is incorporated in a continuously variable transmission mechanism using two hydraulic motors and two hydraulic pumps) adjusts the swash plate of each hydraulic pump and the like of the traveling drive unit 42 to reduce the vehicle speed. Main shift lever 85 for step shifting
Is a seat 11a in the cab 11 as shown in FIG.
Is turned forward and backward by the side operation unit, and when it is tilted forward with respect to the neutral position (stop position) in a substantially vertical posture, it is the forward position. The larger the inclination angle with respect to the vertical, the higher the vehicle speed. When the vehicle is tilted backward, the vehicle retreats, and the vehicle speed increases as the angle of inclination increases.

An auxiliary transmission lever 86, which is also disposed on the side operation portion of the seat 11a, controls an actuator such as a transmission motor for operating a mechanical transmission mechanism (not shown) provided in the HST traveling drive unit 42. When the sub-transmission lever 86 is switched to each of the road traveling mode, the standard operation mode, and the low-speed operation mode, the microcomputer-based control unit (controller unit) 70 mounted on the combine unit issues a command. The output (horsepower) and the number of revolutions of the traveling drive unit 42 adapted in the work mode can be set and maintained in a predetermined range.

When a normal harvesting and threshing operation is performed while the traveling machine 1 is traveling forward (in the low-speed operation mode and the standard operation mode), the power branching mission 39 is used.
OFF (power cutoff) the inflow clutch 48 at
The threshing clutch 48a, the tuning clutch 46, and the reaping clutch 49 are turned on (power connection), and while monitoring the detection values of the fuel injection amount sensor and the vehicle speed sensor, the reaping of the rotational speed tuned to the output of the traveling drive unit 42 is performed. The mowing shaft 47 is driven via the tuning drive shaft 45 to drive the cutting pre-processing device 4 and the feed chain 7 in synchronism, while driving the handling drum drive shaft 40 and the sorting drive shaft 41 to handle the handling drum 11 and the processing drum 2.
9. Fan 20, Fan Karino 19, swing sorting mechanism 1
5 is driven.

Also, when the traveling body is to be turned or retreated during the harvesting and threshing work in the field, when the traveling body 1 is stopped or retracted, and when the drive of the pre-cutting device 4 and the feed chain 7 is stopped. The tuning clutch 46 and the inflow clutch 48 are turned off. To drive only the feed chain 7, the reaping clutch 49 must be turned off.
Change to F. In this case, power is not transmitted to the pre-cutting device 4, but is transmitted only from the power branching mission 39 to the feed chain 7 via the cutting shaft 47.

The elevating position sensor 22 is connected to the traveling body 1
In this embodiment, as shown in FIGS. 3 and 4, a rotary potentiometer type elevation position sensor fixed to the bearing bracket 16, 22 sensing rotation arm 23
Is brought into contact with a sensor shaft 24 fixed to the outer surface of the horizontal cylinder 15, and by detecting the rotation angle θ of the horizontal cylinder 15, the rotation angle of the elevating cylinder frame 14 and, consequently, the cutting pre-processing device for the traveling body 1. 4 is a configuration capable of detecting the vertical position (antibody vertical position).

In the present embodiment, the ultrasonic sensor 20 as a non-contact type cutting height sensor for detecting the cutting height by detecting the ground height between the cutting pre-processing device 4 and the field scene, The back side of the cereal stem raising device 6 which is located on the back surface of the herbaceous body 10 located at the rightmost end in the forward direction among the plurality of herbaceous bodies 10 protruding from the lower front end of the pre-cutting device 4. Upper and lower brackets 10 provided on
It is mounted so as to be adjustable up and down via sensor elevating means 102 provided between 0 and 101. That is, in the lowermost posture of the pre-cutting device 4 in which the lower bracket 101 is substantially parallel to the ground 103, only the rotation is allowed between the upper and lower brackets 100 and 101 so that the screw shaft 104 is substantially vertical. At the upper end of the screw shaft 104, a control motor 105 such as a step motor that can rotate forward and reverse is attached. A support bracket 107 protruding from a nut screwed onto the screw shaft 104 is fitted on a guide shaft 106 parallel to the screw shaft 104, and can only be moved up and down.
As shown in FIG. 8, the axis of the transmitting section (horn section) of the transmitter 20a and the axis of the receiving section (horn section) of the receiver 20b of the ultrasonic sensor 20 are arranged on the support bracket 107 with respect to the ground 103. To be almost vertical. Since the screw shaft 104 is inclined from the vertical line with respect to the ground 103 in accordance with the elevation of the pre-cutting device 4, the axis of the horn portion is always perpendicular to the ground 103 regardless of the inclination. As described above, the tilt sensor and the attitude control motor (both not shown) may be interposed between the ultrasonic sensor 20 and the support bracket 107.

Position sensors 108 and 109 such as limit switches for detecting the height position of the support bracket 107 and thus the installation height of the ultrasonic sensor 20 are provided on the upper and lower portions and the lower portion of the screw shaft 104. As will be described later, when the target cutting height set value is changed and adjusted by the cutting height setting unit 73, when the target cutting height set value is lower than a preset reference value, the higher position sensor 108 So that the ultrasonic sensor 20 is located at a location,
The control device 70 drives the control motor 105. When the target cutting height set value is changed beyond the reference value, the control is performed so that the control motor 105 is driven so that the ultrasonic sensor 20 is located at the position of the position sensor 109 at a lower position. The reference value is stored in the ROM in the control device 70.
Or a RAM (memory).

FIG. 7 shows a functional block diagram of a control device 70 for executing the cutting height control and the automatic clutch control. The control device 70 is an electronic control device such as a microcomputer, which is not shown. A central processing unit (CPU) for executing various arithmetic processes and controls, a read-only memory (ROM) storing a control program, and a read-write memory (RAM) for temporarily storing various detection values, data, and the like ), A nonvolatile memory (flash memory) for holding stored data even when the power of the control device is turned off, a clock as a timer function, an interface, a bus, and the like. Preferably, the reference value is stored in the nonvolatile memory.

An ultrasonic wave is transmitted to the transmitter 20a of the ultrasonic sensor 20 at an appropriate time interval T1 through a transmission drive circuit 71 in accordance with a command from the control device 70, and a reflected wave reflected by an object or the like is reflected. Is received by the receiver 20b, and the detection signal is input to the control device 70 via the reception amplifier circuit 72. The detection signal of the elevation position sensor 22 is also A /
The control device 70 is provided via the D converter at each of the time intervals T1.
To enter.

A variable resistance type (volume type) cutting height setting device 73, a three-position detection type manual switch 76 for performing the threshing operation in a manual mode, and an automatic operation for setting the same operation to an automatic control mode. In order to change the lifting amount and / or the lifting speed of the pre-cutting device 4 to a smaller side when the manual operation is performed by the switch 75, each signal of the foot switch 74 which is turned on and off by the operator by the foot is also controlled. It is input to the device 70. A display unit such as a liquid crystal panel operated by an output from the control device 70 is provided on an operation panel unit which can be viewed by an operator sitting on a seat in the cab 11 so that the cutting height detection value of the ultrasonic sensor 20 can be displayed as a numerical value. is set up.

Further, the control device 70 outputs a predetermined elevating command signal to the first driving circuit 77 and the second driving circuit 78 in accordance with a predetermined calculation result, and responds to the output from the first driving circuit 77. To operate the electromagnetic solenoids 80a and 80b of the hydraulic switching valve 80 in the hydraulic circuit 79, while operating the electromagnetic solenoid 50a of the electromagnetic proportional pressure reducing valve 50 which is an example of a high-speed response electromagnetic valve in response to the output from the second drive circuit 78. Thus, the single-acting hydraulic cylinder 9 for raising and lowering the pre-cutting device 4 is operated.

In the hydraulic circuit 79 shown in FIG. 7, a pair of left and right rolling control hydraulic cylinders for controlling the relative left and right vehicle heights of the single-acting lifting hydraulic cylinder 9 and the right and left traveling devices 3 and the traveling body 1 are provided. Pressure oil is also supplied to a hydraulic control valve 51 and the like (not shown). In this case, as shown in FIG.
A relief valve 54 is inserted in the oil supply path 53 to the fuel cell 9. 4
In the middle of the hydraulic pipe from the output port of the hydraulic switching valve 80 of the port 3 position switching electromagnetic type to the single-acting hydraulic cylinder 9, a check valve 5 is provided.
5 and the slow return check valve 56 are connected. The other output ports of the hydraulic switching valve 80 are configured to supply oil to the other hydraulic control valves 51 at the same time.

A return throttle pipe 57 connected between the check valve 55 of the hydraulic pipe and the slow return check valve 56 has a variable throttle valve 58 for lowering the piston rod of the single-acting hydraulic cylinder 9 and an emergency lowering valve 59. And are connected in parallel. The variable throttle valve 58 is a two-port two-position switching type valve.
The pilot port has one of the aforementioned high-speed response solenoid valves.
The output port of the electromagnetic proportional pressure reducing valve 50 is connected as an example.

The operation control of the hydraulic cylinder 9 for raising and lowering the pre-cutting device 4 is executed as follows. That is, when the hydraulic hydraulic pressure switching valve 80 is switched to extend the hydraulic cylinder 9 (when the pre-cutting device 4 is driven upward).
, The electromagnetic solenoid 80a is controlled by pulse width modulation (PW
M), the pilot pressure appropriately adjusted to the hydraulic pressure by the electromagnetic proportional pressure reducing valve 50 acts on the variable throttle valve 58, the degree of throttle of the variable throttle valve 58 is arbitrarily changed, and the return oil pipe 57 is connected to the oil tank. Drained to 60. In that case,
The operating speed of the hydraulic cylinder 9 is adjusted according to the degree of throttle of the variable throttle valve 58.

When the hydraulic cylinder 9 is reduced (when the pre-cutting device 4 is driven downward), the hydraulic switching valve 80 is set to neutral, and the electromagnetic proportional pressure reducing valve 50 is controlled in the same manner as described above by pulse width modulation control ( The operation is performed by a PWM (PWM) method, and the throttle opening of the variable throttle valve 58 is adjusted by adjusting the pilot pressure, whereby the operating speed of the hydraulic cylinder 9 is adjusted.

Next, the cutting height control will be described. When the automatic switch 75 for setting the automatic mode is turned on, the ultrasonic sensor 2 as a non-contact sensor is used.
The detected value of 0 is input to the control device 70 and the cutting height setting device 7
The calculated value is compared with a preset target cutting height set value in 3 and when the detection value of the ultrasonic sensor 20 is higher,
The pre-cutting device 4 is moved downward through the hydraulic pressure switching valve 80 and the electromagnetic proportional pressure-reducing valve 50, and when the detection value of the ultrasonic sensor 20 is lower, the pre-cutting device 4 is driven up. It is automatically adjusted to reach the target setting cutting height. In these cases, when the deviation between the target cutting height set value and the detection value of the ultrasonic sensor 20 is large, the hydraulic cylinder 9 is driven quickly by the continuous drive signal, and the lifting / lowering speed of the pre-cutting device 4 is increased. If the deviation becomes small, the driving speed of the hydraulic cylinder 9 is reduced by the pulse width modulation control (PWM) method, and the vertical movement speed of the pre-cutting device 4 is reduced to enable fine adjustment of the cutting height.

Next, in the cutting height control by the combine, the target set cutting height value Hsm by the cutting height setting unit 73 is set to be large or small when the normal stock root side is cut and when the high cutting is performed. In this case, control for changing and adjusting the installation height of the ultrasonic sensor 20 will be described. Note that a scale of the target set cutting height value Hsm is provided around the knob in the variable resistance type (volume type) cutting height setting device 73, and this scale is proportional to the VR value (resistance value). It is set as follows.

As shown in FIGS. 9A and 9B,
Since the installation height of the ultrasonic sensor 20 and the installation height of the cutting blade 5 are generally different, the cutting height detection value is obtained by a predetermined conversion from the detection value of the ultrasonic sensor 20. For example, the diagram on the left side of FIG. 9A shows a state in which the pre-cutting device 4 is lowered so that the ground height of the cutting blade 5 is at a low position, and the target set cutting height value Hsm is a reference. This is the case when the value is smaller than the value Hxo. In this case, the ultrasonic sensor 20 is located on the left side of FIG. 9B, that is, the position (high position) indicated by the solid line in FIG.
Is installed. Here, the cutting height (the ground height of the cutting blade 5) is H
Assuming that sn1 and the height of the ultrasonic sensor 20 above the ground are Hx1, and the deviation value Hα1 between the height of the cutting blade 5 and the ultrasonic sensor 20 is Hsn1
= Hx1-Hα1.

On the other hand, the target setting cutting height value Hsm is equal to the reference value Hxo.
If it is larger, the support bracket 107 is located on the right side of FIG.
The ultrasonic sensor 20 is lowered and installed so that is positioned. Here, the cutting height (ground height of the cutting blade 5) is Hsn2, the ground height of the ultrasonic sensor 20 is Hx2, the deviation Hα2 between the cutting blade 5 and the ultrasonic sensor 20 is Hsn2, Assuming that the descending amount from the position where the height is high is Hd, Hα2 + Hd = H
α1. Therefore, Hsn2 = Hx2-Hα2 = Hx2-
(Hα1-Hd).

When the control unit 70 sets the cutting height setting unit 73 so that the target setting cutting height value Hsm is smaller than the reference value Hxo, the target setting cutting height value Hsm and the Hsn1 are set. Then, the mowing pre-processing device 4 is adjusted up and down so as to approach Hsm. On the other hand, when the cutting height setter 73 is set to a state where the target setting cutting height value Hsm is larger than the reference value Hxo, the target setting cutting height value H
Compare sm with the value of Hsn2, and approach Hsm,
What is necessary is just to raise and lower the cutting pretreatment device 4. At this time, H
In order to understand sn1 and Hsn2 by comparison, it is sufficient to correct the cutting height detection value by the change amount Hd in which the ultrasonic sensor 20 is lowered.

In the above-described embodiment, the position sensors 108 and 109 such as limit switches are fixed in advance in accordance with whether or not the target set cutting height value Hsm is higher than the reference value. The amount of change in the elevation height has been determined, but as another embodiment, the target set cutting height value Hsm is set to a reference H by a rotary encoder (not shown) that detects the amount of rotation of the control motor 105 or the screw shaft 104.
Depending on whether it is higher than the xo value, the ultrasonic sensor 20
Is calculated by an arithmetic unit of the control device 70, and the rotary encoder detects the amount of elevation so that the control motor 105 is operated and stopped by the amount of operation. Then, the control device 70 may be configured to correct the cutting height detection value by the change amount obtained by lowering (upward) the ultrasonic sensor 20.

In any case, if the target cutting height set value Hsm is equal to or greater than the predetermined reference value Hxo as described above, the height of the ultrasonic sensor 20 above the ground becomes too large, and the detection signal ( Since the received signal of the reflected wave becomes unstable, the height of the ultrasonic sensor 20 is changed and adjusted to a lower position, the detection result by the ultrasonic sensor 20 is stabilized, and the reliable cutting height control is executed. You can do it.

FIGS. 10 (a) and 10 (b) show attitude correction means for controlling the attitude of the ultrasonic sensor 20 so that the orientation of the ultrasonic sensor 20 becomes substantially perpendicular to the ground 103 when the pre-cutting device 4 is moved up and down. And an example in which the sensor elevating means is integrated with the motor 1
A support arm 11 pivotally attached to the upper and lower pivots via
At 0, an ultrasonic sensor 20 is mounted via a drive motor 111 for attitude control, and an inclination angle sensor 112 and a controller 113 are mounted.

When the target set cutting height value Hsm is set lower than the reference value Hxo, as shown in FIG. 10A, the support arm 110 is driven up and down so that the horizontal or the position where the ultrasonic sensor 20 is installed is raised. The motor 114 is operated, and the drive motor 111 for attitude control is operated based on the detection result of the inclination angle sensor 112 to maintain the direction of the ultrasonic sensor 20 so as to be substantially perpendicular to the ground 103.

When the target set cutting height value Hsm is set higher than the reference value, as shown in FIG. 10 (b), the lifting drive motor 11 is moved so that the free end side of the support arm 110 is lowered.
4 is operated, and the drive motor 111 for attitude control is operated based on the detection result of the inclination angle sensor 112 to hold the direction of the ultrasonic sensor 20 so as to be substantially perpendicular to the ground 103.

By mounting a rotary encoder on the lifting motor 114, the amount of vertical movement of the ultrasonic sensor 20 mounted on the support arm 110 is detected, and the detection of the ultrasonic sensor 20 is performed as in the above embodiment. The control may be performed so as to correct the value. If the ultrasonic sensor 20 is not adjusted to move up and down as described above, if the target setting cutting height value Hsm is set higher than the reference value Hxo, the detection signal of the ultrasonic sensor 20 becomes unstable. When the target cutting height set value Hsm by the height setting unit 73 is set higher than the reference value Hxo, even if it is determined that the cutting height detection value based on the detection signal is higher than the target cutting height set value Hsm, A control unit configured to execute control for inhibiting the lowering control of the pre-cutting device 4 is provided. Thus, even if the cutting height is determined to be higher than the target height according to the detection signal of the ultrasonic sensor 20, the cutting height is actually low, and when the pre-cutting device 4 is further lowered, the weeding body 10 and the like are removed. However, it is possible to prevent inconveniences such as piercing the ground 103, damaging parts, and taking the soil together with the culm into the threshing apparatus.

In each of the above embodiments, the ultrasonic sensor has been described as an example of the non-contact type cutting height sensor. However, the cutting height is measured by irradiating infrared rays toward the ground and detecting the amount of reflection. The same problem as the present invention can be solved by the infrared sensor described above, and the same predetermined effect can be obtained.

[0041]

As described above in detail, the cutting height control device in the combine according to the first aspect of the present invention enables the cutting pre-processing device to move up and down with respect to the front part of the traveling machine body by the lifting drive means. The cutting drive unit is operated by comparing a detection signal of a non-contact type cutting height sensor for detecting a ground height of the cutting pre-processing device with a target cutting height set value by a cutting height setting device. In the cutting height control device in the combine configured as described above, a sensor lifting means for raising and lowering the arrangement height of the non-contact type cutting height sensor is provided, and a target cutting height set value by the cutting height setting device is provided. Is set higher than the reference value, a control means is provided for controlling the movement of the arrangement height of the non-contact type cutting height sensor in a lower direction by the sensor elevating means.

If the arrangement height of the non-contact type cutting height sensor becomes high, the disturbance of the reflected wave becomes large and the detection result becomes unstable. If the value is set higher than the value, the sensor raising / lowering means is operated to lower the arrangement height of the non-contact type cutting height sensor, thereby eliminating the instability. According to a second aspect of the present invention, in the cutting height control device for a combine according to the first aspect, the control unit includes a storage unit that stores the reference value and a storage unit that stores the reference value. A calculating means for calculating an operation amount for operating the sensor elevating means, and the non-contact type cutting height sensor according to a height change amount obtained by changing an arrangement position height of the non-ground type cutting height sensor. Correction means for correcting the value of the detection signal.

According to this configuration, when the arrangement position height of the non-grounding type cutting height sensor is changed, the same ground height is set.
Since a deviation occurs between the detection value detected by the sensor and the detection value by the non-ground type cutting height sensor at a normally fixed position, the value of the detection signal is corrected by the correction means, so that the non-ground type cutting height sensor is corrected. Even if the height sensor is moved up and down, an effect of always being able to detect an accurate cutting height can be obtained.

According to a third aspect of the present invention, in the cutting height control apparatus for a combine according to the first or second aspect, the non-contact type cutting height sensor is constituted by a reflection type ultrasonic sensor. The sensor elevating means includes attitude correcting means for correcting the direction of emission and reception of ultrasonic waves so as to be substantially perpendicular to the ground. According to the present invention, when the pre-cutting device is moved up and down around the predetermined rotation fulcrum, the direction of the ultrasonic sensor mounted on the pre-cutting device changes, and an error occurs in the detection result of the cutting height. Therefore, the height of the ground (cutting height) can be accurately detected by the attitude control described above.

According to a fourth aspect of the present invention, there is provided a cutting height control device for a combine, wherein the cutting pre-processing device is configured to be able to move up and down with respect to a front portion of the traveling machine body by means of a lifting drive means. The cutting height of a combine configured to operate the elevation drive means by comparing a detection signal of a non-contact cutting height sensor for detecting a ground height of the ground with a target cutting height set value by a cutting height setter. In the control device, when the target cutting height set value by the cutting height setting device is set higher than a reference value, it is determined that the detected cutting height by the detection signal is higher than the target cutting height set value. Even
A control means configured to execute control for prohibiting the lowering control of the mowing pre-processing device is provided.

In the case where the non-contact type cutting height sensor is not adjusted, if the target setting cutting height value is set higher than the reference value, the detection signal of the sensor becomes unstable. If the target cutting height set value according to is set higher than the reference value, even if it is determined that the cutting height detection value by the detection signal is higher than the target cutting height set value, the lowering control of the cutting preprocessing device is performed. There is provided control means configured to execute prohibiting control. Thereby, even if it is determined that the cutting height is higher than the target height according to the detection signal of the sensor, the cutting height is actually low, and when the cutting pre-processing device is further lowered, the lower end of the cutting device is pushed into the ground. It is possible to prevent inconvenience such as damaging the soil and bringing the soil into the threshing device together with the culm.

[Brief description of the drawings]

FIG. 1 is a side view of a combine.

FIG. 2 is a plan view of the combine.

FIG. 3 is a front view of the combine.

FIG. 4 is a side view showing a mounting position of a position sensor.

FIG. 5 is a plan view showing a mounting position of a position sensor.

FIG. 6 is a skeleton diagram of a power transmission system.

FIG. 7 is a functional block diagram of a hydraulic circuit and control means.

FIG. 8 is a side view showing the elevation adjustment means of the ultrasonic sensor.

9A is an explanatory diagram showing a difference in detection value due to a difference in arrangement height of an ultrasonic sensor, and FIG. 9B is a diagram showing an ultrasonic sensor according to whether or not a target cutting height set value is larger than a reference value; It is explanatory drawing which shows the state which changes installation height.

10A is an explanatory diagram illustrating a state of attitude control when the height of the ultrasonic sensor is increased, and FIG. 10B is a diagram illustrating a state of attitude control when the height of the ultrasonic sensor is decreased. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Running body 4 Cutting pre-processing device 5 Cutting blade 6 Grain raising device 20 Ultrasonic sensor 70 Control device 73 Cutting height setting device 102 Sensor elevating means 104 Screw shaft 105 Control motor 106 Guide shaft 107 Support bracket 108,109 Position sensor

Continuation of the front page (72) Inventor Taiji Mizukura 1-32 Chaya-cho, Kita-ku, Osaka City Inside Yanmar Agricultural Machinery Co., Ltd.

Claims (4)

[Claims] A cutting pre-processing device is configured to be able to move up and down with respect to a front part of a traveling machine body by a lifting drive means, and a detection signal of a non-contact type cutting height sensor for detecting a ground height of the cutting pre-processing device. And a cutting height control device in a combine configured to operate the lifting / lowering driving means by comparing a target cutting height set value by a cutting height setter, wherein the arrangement height of the non-contact type cutting height sensor is provided. When a target cutting height set value by the cutting height setting device is set higher than a reference value, a non-contact type cutting height sensor is arranged by the sensor raising / lowering device. A cutting height control device for a combine, comprising control means for controlling the movement of the height in a lower direction. 2. The control unit includes: a storage unit configured to store the reference value; a calculation unit configured to calculate an operation amount for operating the sensor elevating unit according to the stored reference value; 2. The apparatus according to claim 1, further comprising: a correction unit configured to correct a value of a signal detected by the non-contact type cutting height sensor according to a height change amount obtained by changing a height of an arrangement position of the cutting height sensor. The cutting height control device in the combine according to claim 1. 3. The non-contact type cutting height sensor is constituted by a reflection type ultrasonic sensor, and the sensor elevating means is arranged such that the direction of emission and reception of ultrasonic waves is substantially perpendicular to the ground. The cutting height control device for a combine according to claim 1 or 2, further comprising a posture correcting means for correcting the cutting height. 4. A non-contact type cutting height sensor for detecting a height of the cutting pre-processing device with respect to a ground, wherein the cutting pre-processing device is configured to be able to move up and down with respect to a front portion of the traveling machine body by a lifting drive means. And a cutting height control device in a combine configured to actuate the lifting / lowering drive means by comparing the target cutting height setting value with a cutting height setting device, wherein the target cutting height setting by the cutting height setting device is performed. When the value is set higher than the reference value, even if it is determined that the cutting height detection value based on the detection signal is higher than the target cutting height set value, control is performed to prohibit the lowering control of the pre-cutting device. A cutting height control device in a combine, comprising a control means configured as described above.