JPH0143524B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a sensor that continuously detects the cutting height of a cutting section that is connected to the machine so that it can be raised and lowered by a drive, and adjusts the cutting height based on the detected value of this sensor. The reaping device is operable to selectively switch between a mechanism for automatically driving and controlling the reaping section and a mechanism for controlling the elevating and lowering of the reaping section based on manual operation so that the reaping section is maintained within a set range. This invention relates to a cutting height control device for a harvester.

In this type of cutting height control device of a reaping/harvesting machine, when the automatic cutting height control mechanism is activated, the sensor also detects stones, straw waste, etc. present in the field, and abnormal detection values frequently occur. This has the drawback of causing large variations in the cutting height due to repeated inappropriate elevation control of the cutting section based on this abnormality detection value. Therefore, if the above-mentioned abnormal detection values occur frequently and the automatic cutting height control mechanism cannot perform appropriate cutting height control,
It is desirable to switch from the automatic cutting height control state to the manual cutting height control state, but in the past, the operation of both control mechanisms was manually operated based on the operator's judgment, so the abnormality detection value It is difficult to judge when this occurs and whether it is temporary or not, leading to variations in cutting height due to delayed switching or forgetting to switch, or when a temporary abnormality is detected but manual The disadvantage is that it takes a lot of time and effort to switch to the cutting height control state and control the cutting height.

In view of the above-mentioned circumstances, the present invention relieves the operator from the complicated cutting height control as much as possible, while also changing the automatic cutting height control state to the manual cutting height control state when abnormal detection values occur frequently as described above. The purpose is to enable accurate and rapid switching to a controlled state.

The cutting height control device for a reaping harvester according to the present invention includes:
In the above, a mechanism for determining whether or not a value detected by the sensor is abnormal when the automatic cutting height control mechanism is activated, and if it is abnormal, the number of occurrences of the value is set within a set time. The present invention is characterized by being provided with a mechanism that automatically switches from the operating state of the automatic cutting height control mechanism to the operating state of the manual cutting height control mechanism when the above is reached, so that the cutting height control mechanism is automatically switched to the operating state of the manual cutting height control mechanism. In the temporary case where the number of abnormal detected values does not reach the established number of times, the automatic cutting height control state is maintained to relieve the operator from the complicated cutting height control while the abnormal detected values are If this occurs frequently, the above-mentioned switching mechanism, which operates based on this, can accurately and quickly switch from the automatic cutting height control state to the manual cutting height control state. It has now been possible to successfully suppress variations in cutting height caused by forgetting.

Embodiments of the present invention will be described below based on the drawings.

As shown in FIG. 1, at the front of the machine 3, which is equipped with a pair of left and right crawler traveling devices 1, 1 and a threshing device 2, a pair of left and right pulling devices 4, 4, a clipper-type reaping device 5, and The harvested grain culm is transferred to the threshing device 2.
A reaping section 8 equipped with a device 7 for conveying and supplying to the feed chain 6 is arranged so as to be vertically movable. A combine harvester, which is an example of a reaping harvester, is constructed by interposing a hydraulic cylinder 11 for driving and lowering the 8.

Further, as shown in FIGS. 2 and 3, a sensor 12 is provided to detect the cutting height of the reaping section 8, and the cutting height is maintained within a set range based on the detected value of this sensor 12. A mechanism 13 for automatically driving up and down the reaping section 8 and a mechanism 14 for controlling up and down the reaping section 8 based on manual operation are selectively switchable and operable by operating a switch 15. There is.

The sensor 12 is connected to an ultrasonic ceramic microphone 16 and a transmitting circuit 17 that transmits ultrasonic waves a toward the field on the mowed field side for a set time Δt every set time _t1 , as shown in FIG. The ultrasonic transmitter 12A and the reflected wave b from the field scene
An ultrasonic receiver 12B includes an ultrasonic ceramic microphone 18 that receives the waves, and a receiving circuit 19 that amplifies the waves received from the microphone 18.
are arranged in one case 20 fixed to the back of the raising device 4, and from the time when the ultrasonic wave is transmitted from the transmitter 12A to the time when the reflection plate of the ultrasonic wave is received by the receiver 12B. A mechanism 21 that measures the time t ₂ required for
A mechanism 22 that calculates the height above the ground, that is, the cutting height.
It is configured by providing.

The automatic cutting height control mechanism 13 compares the calculated detection value from the calculation mechanism 22 with the set cutting height from the setting device 23 that can change the desired cutting height, and adjusts the calculated detection value based on the comparison result. said hydraulic cylinder 1 so that the value is maintained within the permissible range of the set value.
A control unit 2 that automatically controls the operation of solenoids 24a and 24b of a control valve 24 for 1
It consists of 5.

The manual cutting height control mechanism 14 includes a switch 26 for operating the ascending solenoid 24a of the control valve 24 and a descending solenoid 24b.
The switch 27 is configured to operate the switch 27.

A mechanism 28 determines whether or not the value detected by the sensor 12 is abnormal when the automatic mowing height control mechanism 13 is activated, and if the value is abnormal, the number of occurrences of the value is within a set time. A mechanism 29 is provided which automatically switches from the operating state of the automatic cutting height control mechanism 13 to the operating state of the manual cutting height control mechanism 14 via the switch 15 when the cutting height exceeds the set value.

Also, a mechanism 3 for expanding the dead band width B for the ultrasonic waves received by the receiver 12A more than usual.
0 and the information from the transmitting circuit 17 to detect whether or not the microphone 16 is in the transmitting state, and when the microphone 16 is in the transmitting state,
A timer circuit 31 is provided to automatically operate the dead band width expanding mechanism 30 for the set time Δt that is about to be transmitted, and the reaping section is provided for the set time Δt after the transmitter 17 enters the transmitting state. A control check mechanism 32 that disables the automatic cutting height control of No. 8 is configured. When such a control check mechanism 32 is provided, even if the transmitted vibration c of the transmitter 12A is propagated to the receiver 12B via the case 14, the reaping unit 8 may be unduly raised to the cutting height based on this vibration. It is possible to stabilize cutting height control without being controlled.

[Brief explanation of drawings]

The drawings illustrate an embodiment of the cutting height control device for a reaping/harvesting machine according to the present invention; FIG. 1 is a side view of the front part of the combine, FIG. Block diagram showing the height control system, Figure 4A,
B is an explanatory diagram showing the transmission state and reception state of ultrasonic waves. 3...Main machine, 8...Reaping section, 12...Sensor, 13...Automatic cutting height control mechanism, 14...Manual cutting height control mechanism, 28...Discrimination mechanism, 29...Switching mechanism.

Claims (1)

[Claims] 1. A sensor 12 that continuously detects the cutting height of the cutting section 8 that is connected to the machine 3 so as to be able to move up and down.
and a mechanism 13 that automatically controls the drive up and down of the reaping section 8 based on the detected value of the sensor 12 so that the cutting height is maintained within a set range, and a mechanism 13 that automatically controls the reaping section 8 to raise and lower the reaping section 8 based on a manual operation. Mechanism 14 for controlling elevation
In the cutting height control device for a reaping/harvesting machine, which is provided so as to be able to operate by selectively switching between the sensor 12 and
A mechanism 28 for determining whether the detected value is abnormal or not, and if the value is abnormal, when the number of occurrences of the value reaches a set value or more within a set time, the automatic mowing height control mechanism 13 is A mowing height control device for a reaping harvester, characterized in that a mechanism 29 is provided for automatically switching the manual mowing height control mechanism 14 to an operating state. 2. The cutting height control device for a reaping harvester according to claim 1, wherein the sensor 12 uses ultrasonic waves.