JPS6235729B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a detection signal from a culm length detection section that detects the length of a grain culm and a conveyance device that is connected to a handling depth adjustment device. The present invention relates to a method for adjusting the handling depth of a combine harvester in which the position of a conveying device is adjusted in accordance with the grain culm length to be supplied in association with an adjusting device for adjusting the handling depth position to obtain an appropriate handling depth.

[Conventional technology]

The conventional method for adjusting the handling depth of combine harvesters is as follows:
A grain culm conveying device is provided between the reaping device and the starting end of the grain culm automatic feed chain of the threshing device to convey the reaped grain culm in a horizontally lying position. A sensing device is installed at the passing point, and an adjusting device is installed at the stock end, and regardless of the length of the grain culm, the adjusting device operates in conjunction with the sensing action of the sensing device to adjust the handling depth of the grain culm. (See Japanese Unexamined Patent Publication No. 49-41113).

[Problem that the invention seeks to solve]

The above conventional structure adopts a structure in which the sensing device that detects the length of the grain culm acts on the tip of the grain culm in a horizontally lying position after being raised and reaped. Due to its own weight and friction against the conveying part, the posture of this conveyed grain culm becomes disturbed and fluctuates,
As a result, there is a drawback that the culm length cannot be detected correctly, and since the sensing device is composed of a single sensor, there is a drawback that hunting occurs in controlling the handling depth due to the inertia of the actuator.

Furthermore, there is also the drawback that hunting occurs due to rapid changes in culm length.

In order to solve this problem, it is necessary to constantly adjust the manual lever, and the operation of the aircraft becomes complicated.

The purpose of the present invention is to solve these drawbacks of the conventional structure, and to make it possible to accurately detect the length of the grain culm and to more effectively eliminate the hunting phenomenon in terms of handling depth control. shall be.

[Means for solving the problems] The structure of the present invention to achieve the above object is as follows:
To explain according to the examples shown in FIGS. 1 to 4 corresponding to the embodiment, the present invention is capable of measuring the length of the grain culm in an upright position on the upper side of the transport device 8 for adjusting the handling depth. A culm length detecting section 6 is provided to detect the culm length, and a position detecting section B is provided which is connected to the conveying device 8 and detects the position of the conveying device. In order to adjust the handling depth by changing the position of the conveying device 8 so as to match the detection signals from both of the detection sections 6 and B, a predetermined width is given to the signal level of at least one of both detection signals. Compare the detected signals. Further, the actuator 12 for changing the position of the conveying device is driven only when a control signal for adjusting the handling depth is continuously output for a predetermined period of time based on the comparison result.

[Effect]

The culm length is detected in the standing posture before reaching the conveying device 8 for adjusting the handling depth and taking the horizontally lying posture. Therefore, detection is possible under conditions where there are no factors that disturb or change the attitude of the transported grain culm, such as the dead weight of the ear tip or friction against the transport section, and accurate culm length can be detected. Further, when both detection signals are at a constant level, the position of the transport device 8 is changed as soon as there is even a slight difference between the two detection signals. At this time, if the conveyance device overruns, a difference occurs again between the two detection signals, and as a result, the conveyance device is now displaced in the opposite direction, and by repeating this, the conveyance device 8 is However, in the present invention, since a predetermined width is given to the signal level of at least one of both detection signals, the overrun of the transport device can be absorbed, and hunting can be effectively suppressed.

In addition to the above-mentioned factors, hunting in the conveying device is caused by the presence of long culms, short culms, and even tall weeds in a small portion of the grain culms being conveyed. However, since the detection is temporary and one-off and does not last for a long time, such short-term detection should be ignored and treated based on the above comparison results. Unless a control signal for adjusting the depth is continuously output for a predetermined period of time, a signal for driving the actuator for changing the position of the conveying device is not output. Therefore, even if there is such a temporary or isolated presence of long or short culms or the presence of tall weeds, the actuator for changing the position of the conveying device will not be displaced unnecessarily, and hunting at such points will not occur. can also be successfully prevented.

〔Example〕

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

FIG. 1 shows an overall front view of a combine harvester according to the present invention. In the same figure, reference numeral 1 denotes a lifting device installed obliquely toward the rear and upward in the front part of the machine body, and by the action of lifting claws 2... Raise the planted grain culm to a nearly upright position. The lifting case 3 of this lifting device 1,
3' includes light emitting and light receiving elements 4a, 5a, 4b,
Culm length detection sensor consisting of a pair of 5b, 4c, and 5c
A detection unit 6 in which a plurality of Sa, Sb, and Sc are provided in the vertical direction with elements 4a, 4b, 4c and 5a, 5b, 5c facing each other to detect the length of the grain culm.
It consists of (See Figure 2).

Reference numeral 7 denotes a cutting blade that acts to reap the stock base of the planted grain culm raised by the lifting device 1, and 8 conveys the cut grain culm to the starting position of the feed chain 10 of the threshing section 9. It is a transport device. As shown in FIG. 3, this conveying device 8 has an intermediate portion rotatably supported by a swinging rod 11, and a starting end that responds to the reciprocating motion of a hydraulic cylinder 12, which is an example of an actuator. It is pivotally supported by an arm rod 13 that interlocks and swings around the P position, and as the hydraulic cylinder 12 reciprocates, the terminal end of the conveying device 8 moves in the direction of arrow A with respect to the starting end of the feed chain 10. , A' directions, thereby adjusting the handling depth in the threshing section 9.

In addition, 14 in FIG. 3 is a solenoid valve that controls the operation of the hydraulic cylinder 12, and includes a pair of solenoids.
Equipped with SOL ₁ and SOL ₂ . This solenoid
SOL ₁ and SOL ₂ are connected to output terminals of a transport device driving circuit, which will be described later, and either one is energized in response to a command from the detection section 6 that detects the length of the grain culm.

FIG. 4A shows a culm length detection circuit, and FIG. 4B shows a drive circuit for the conveying device 8 for controlling the handling depth.

In the figure, PTa is a phototransistor used as the light receiving element 5a of the detection section 6, and the output of this transistor PTa is connected to a well-known multi-stage transistor amplifier circuit Amp and a time delay circuit Ta.
Through the relay is led to Rya.

The above relay Rya is the phototransistor
When PTa receives light from light emitting element 4a and is in a conductive state, it is not energized and relay contact a ₁ is connected as shown in the figure.
is open and A ₂ is closed. On the other hand, when the light from the light emitting element 4a is blocked by the grain culm raised by the raising device 1 and the phototransistor PTa is in a non-conductive state, the relay Rya is energized and the relay contact _a1 is closed. Open a ₂ .

Incidentally, the time delay circuit Ta is connected to the detection unit 6 when the grain culm is detected.
This is provided in order to compensate for the time from when the grain passes through the threshing section until it is carried into the threshing section 9.

That is, instead of immediately controlling the handling depth in response to the culm length detection command from the culm length detection section 6,
The handling depth control is performed by delaying the time until the grain culm passes the culm length detection position and is introduced into the threshing section 9, and the grain culm whose handling depth has already been properly controlled is directly threshed. In addition, the handling depth control is performed for the first time on the grain culm whose handling depth is to be controlled, and a time delay circuit Ta is configured here.

Although not shown, other light-receiving elements 5
Similarly to the light receiving element 5a, phototransistors are used in the phototransistors b and 5c, and they are guided to the relay via a multi-stage transistor amplifier circuit and a time delay circuit, and the phototransistors are turned on and off by the phototransistors. The relay is configured to be de-energized and energized to open and close the respective relay contacts b ₁ , b ₂ , c ₁ , and c ₂ .

Each of the relay contacts a ₁ , a ₂ , b ₁ , b ₂ , c ₁ , c ₂ is
As shown in the figure, the constant voltage Vst is applied to each terminal t ₁ , t ₂ ,
Each of the terminals t ₁ , t _{2 ,} of the resistor R that divides the voltage at t _{3 ,} t 4
It is connected between t ₃ , t ₄ and the negative terminal of the first comparator Comp ₁ and the positive terminal of the second comparator Comp ₂ , and is By opening and closing, a piezoelectric voltage is applied to the terminals of the comparators COmp ₁ and Comp ₂ along the long and short sides of the grain culm.

For example, since the grain culm is long, all the light receiving elements 5a, 5
If b and 5c are optically blocked, each of the above relays
In order to energize Rya..., relay contacts a ₁ , b ₁ , c ₁ are closed and a ₂ , b ₂ , c ₂ are opened, then t ₄ →c ₁ →b ₁ →a ₁
A relatively high voltage divided at the terminal t ₄ is applied to the negative terminal of the first comparator Comp ₁ and the positive terminal of the second comparator Comp ₂ . Moreover, the light receiving elements 5a and 5 are formed by a grain culm that is somewhat shorter than the grain culm.
If b is optically blocked, then the relay contact
Since a ₁ , b ₁ , and c ₂ are closed and a ₂ , b ₂ , and c ₁ are open, terminal t ₃
The voltage divided by the voltage is applied to the terminals of the comparators Comp ₁ and Comp ₂ . Furthermore, when the grain culm length becomes shorter,
The voltages applied to the terminals of the comparators Comp ₁ and Comp ₂ decrease sequentially to the voltage divided by the terminal t ₂ and the voltage divided by the terminal t ₁ .

Next, a variable resistor is connected in parallel to the resistor R.
R′ is connected, and the voltage Vv divided by the variable terminal tv is directly sent to the negative terminal of the second comparator Comp ₂ , and the voltage V′v which is somewhat reduced by the adjustment resistor Rj is applied to the positive terminal of the first comparator Comp ₁ .

This variable resistor R' is configured to move the variable terminal tv in accordance with the amount of operation of the hydraulic cylinder 12 to change the magnitude of the divided voltage.

In other words, the variable terminal tv responds to the handling depth, and moves downward to lower the divided voltage when handling is deep, and moves upward to increase the divided voltage when handling shallow. The current handling depth position of the conveying device 8 can be detected based on the divided voltage, that is, the variable terminal tv connected to the conveying device 8 via the cylinder 12 can be detected. Mainly,
A handling depth position detection section B of the conveying device 8 is configured.

The comparators Comp ₁ and Comp ₂ each operate to generate an output voltage only when the voltage applied to the positive terminal is higher than the voltage applied to the negative terminal. Therefore, the first comparator Comp ₁ receives the voltage Vs divided by any terminal t ₁ , t ₂ , t ₃ , t ₄ of the resistor R.
, the voltage divided by the variable terminal tv of the variable resistor R′ and lowered by the adjustment resistor Rj
produces an output voltage when V′v is higher. In other words, the first comparator Comp ₁
An output voltage is generated when the handling depth is shallower than the handling depth suitable for the grain culm length detected by the detection unit 6.

On the other hand, the second comparator Comp ₂ generates an output voltage when the conveying device 8 is at a deeper handling position than the handling depth suitable for the grain culm length detected by the detection unit 6. Therefore, the conveyance device 8 is connected to the detection section 6.
Unless the grain culm length detected by
Output voltage is generated from Comp ₁ and Comp ₂ .

That is, the constant voltage Vst is divided by the resistor R based on the command from the culm length detection section 6, and the handling depth position where the conveying device 8 should be is detected based on the divided voltage. A detection signal of the current handling depth position and a detection signal of the current handling depth position by the handling depth position detection section B are detected by first and second comparators.
By inputting to Comp ₁ and Comp ₂ , it is possible to compare whether the handling depth of the conveying device 8 should be controlled to the deep handling side or the shallow handling side and output an output signal, Both comparators
Comp ₁ and Comp ₂ constitute a comparison circuit Comp that adjusts the displacement of the conveying device 8 to control the handling depth.

The adjustment resistor Rj applies a voltage V'v, which is a somewhat lower voltage Vv divided according to the treatment depth, to the first comparator Comp ₁ and then to the second comparator Comp ₂ . The difference (Vv
−V′v＞0), and the comparison circuit
It constitutes an adjustment circuit C to stabilize Comp.

That is, without the adjustment resistor Rj, the same voltage Vv divided according to the handling depth would be applied to both comparators Comp ₁ and Comp ₂ , so this voltage Vv and the voltage according to the command from the detection unit 6 would be applied to both comparators Comp 1 and Comp 2. If there is even a slight voltage difference between the two and Vs, one of them, for example, the comparator Comp ₁ , will issue an output signal, the cylinder 12 will be actuated, and the conveying device 8 will be controlled to the deep handling side. At this time, when the conveying device 8 overruns the predetermined handling depth position, the other comparator Comp ₂ immediately issues an output signal to control the shallow handling side, and by repeating this, the aforementioned conveying device 8 causes hunting in handling depth control, and as a result, negative feedback is applied via the variable resistor R' due to the expansion and contraction movement of the hydraulic cylinder 12, causing vibration in the circuit. This is prevented by providing a resistor Rj.

15 and 15 are resistors, and 16 and 16 are capacitors. Even if any of the sensors Sa, Sb, and Sc of the culm length detection unit 6 detects short culms, long culms, or tall weeds for a short time, capacitor 16,16
The smoothing circuit D is configured so that the output signal is not passed if the time is insufficient to charge the battery.

Through this smoothing circuit D, the switch circuit SW ₁ ,
When an output signal is issued to SW ₂ , relay Ry ₁ ,
Ry ₂ and its relay contacts S ₁ and S ₂ are energized, and one relay contact S ₁ connects the solenoid SoL ₂ of the solenoid valve 14 connected in series to the power source E, and the other relay contact S ₂ energizes SoL ₁ , operates the hydraulic cylinder 12, and controls the handling depth of the conveying device 8 until the output signal from the comparator circuit Comp is stopped.

In the above configuration, for example, when the threshing section 9 is in a shallow handling state, if the grain culm raised by the raising device 1 is short and only the light receiving element 5a is blocked by the tip side, the time delay circuit After a predetermined time delay at Ta, relay Rya is energized to switch its contacts a ₁ and a ₂ from the state shown. Then, the voltage Vs divided by the terminal t ₂ of the resistor R
is added to comparators Comp ₁ and Comp ₂ . At this time, since the threshing section 9 is treated shallowly, the voltage Vv divided to the variable terminal tv of the variable resistor R' and the voltage V'v reduced through the adjustment resistor Rj are the terminals of the resistor R. It is larger than the voltage Vs divided by t ₂ , so the first comparator Comp ₁ generates an output voltage, drives the switch circuit SW ₁ to conduct, and energizes the solenoid valve operating relay Ry _1. . Then relay contact S ₁
closes and energizes solenoid SoL ₂ , solenoid valve 14
is switched to operate the hydraulic cylinder 12 and swing the conveying device 8 in the deep handling direction.

On the other hand, since the operation of the hydraulic cylinder 12 is detected by the variable resistor R' and is negatively fed back to the first comparator Comp ₁ via the variable terminal tv,
The hydraulic cylinder 12 operates and stops until the comparator Comp ₁ no longer produces an output.

In this way, the swinging of the conveying device 8 is stopped, and the handling depth at that time is adjusted to a handling depth suitable for the grain culm length detected by the detection unit 6. And for example,
When the threshing section 9 is in a deep handling state, if the grain culm raised by the raising device 1 is long and the light receiving elements 5a, 5b, 5c are blocked by the tip side of the grain, the second The comparator Comp ₂ generates an output voltage, drives the switch circuit SW ₂ to conduct, closes the relay contact S ₂ , energizes the solenoid SoL ₁ , switches the solenoid valve 14, activates the hydraulic cylinder 12, and transports in the deep handling direction. This causes the device 8 to swing.

Incidentally, the culm length detection section 6 is connected to the light emitting elements 4a, 4b, 4
c and light-receiving elements 5a, 5b, and 5c, but it can be changed to, for example, detecting the length of the grain by contact with the grain culm using a micro switch or the like.

〔Effect of the invention〕

As explained above, the method for adjusting handling depth in a combine harvester according to the present invention involves causing the culm length detection section to act on the grain culm in an upright position on the upper side of the conveyor than the conveying device for adjusting the handling depth. Targeting a raised grain culm or a grain culm in an elongated state after being raised, the culm length can be accurately detected even if it is a soft culm or a grain culm with a heavy ear. Therefore, highly accurate handling depth control can be performed.

In addition, handling depth control that handles overruns of the transport device and suppresses hunting can be performed even better and with higher precision.In addition, there is no need for frequent adjustments using manual levers as in conventional structures, making the aircraft easier to operate. In addition, even if the culm length detecting section detects long culms, tall weeds, or short culms, this should not be used as a criterion for controlling the handling depth. Hunting was also successfully prevented, making it possible to more effectively prevent hunting, thereby avoiding delays in the response of the conveying device, problems with the drive system, errors in handing over grain culms, and disturbances in the conveying posture.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is an overall front view of the combine harvester, Fig. 2 is a side view of the front part of the machine, Fig. 3 is an explanatory diagram showing the operating state of handling depth adjustment, and Fig. 4 Figure A is a culm length detection circuit diagram, and Figure 4B is a transport device drive circuit diagram. 6... Culm length detecting section, 8... Conveying device, 12... Actuator for changing the position of the conveying device, B... Position detecting section, D... Smoothing circuit.

Claims (1)

[Claims] 1. A culm length detection unit 6 that detects the length of the grain culm in an upright position on the upper side of the transport device 8 for adjusting handling depth, and a culm length detection unit 6 that is connected to the transport device 8 and detects the position of the transport device 8. A position detection section B is provided, and when adjusting the handling depth by changing the position of the conveying device 8 so that the detection signals from both detection sections 6 and B match, the signal level of at least one of both detection signals is adjusted. Both detection signals are compared by giving a predetermined width, and the transfer device position changing actuator 12 is activated only when a control signal for adjusting the handling depth is continuously output for a predetermined time based on the comparison result. A method for adjusting the handling depth in a combine harvester, characterized by driving the combine harvester.