JP2006166813A - Working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a working machine such as a rice planting machine for transplanting seedlings, constituted so as not to cause mud pushing, etc., by float without setting up hunting of an operation device when grounding the operation device to a field and returning sensitivity of oil pressure from insensitive side to a set value. <P>SOLUTION: When carrying out sensitivity control by lowering the operation device, detecting grounding of a planting part (a body to be detected) to a field and controlling opening of a hydraulic valve, the position of a detection wire is set to 11/11 (insensitive side) when lowering of the operation device is started and after detecting grounding of the body to be detected is detected, sensitivity is slowly changed for a 1.5 sec (1-2 sec) to an intermediate position between a set detection sensitivity on insensitive side and a detection sensitivity 1/11 (on sensitive side) at the time of operation and for 3 sec (2-4 sec) to a detection sensitivity 1/11 at the time of operation to prevent induction of hunting and mud pushing by changeover of detection sensitivity. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a working machine that connects a working device to a traveling machine body so as to be movable up and down, and controls a ground height of the working device based on a change in posture by sensing a soil pressure of a sensing body provided in the working device.

  The working device is connected to the traveling machine body so as to be movable up and down, and the raising and lowering control is performed so that the height of the working device against the mud surface is maintained at a predetermined value based on the posture change of the detecting body arranged in the working device. In order to prevent the hunting that occurs when the work device is lowered with respect to the farm scene and the detection body comes into contact with the top surface of the farm, the work machine is designed to perform work such as rice planting. When lowering, the sensitivity of the hydraulic pressure for detecting the displacement of the detection body is set to the insensitive side, the ON operation of the planting clutch for operating the work device is detected, or the change in the lift angle of the work device per unit time ( There is known a working machine that detects that the detection body is in contact with a farm scene) and returns the hydraulic pressure sensitivity to a predetermined set value (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2003-284413 (page 3, FIG. 5)

  However, as in the prior art, when the sensitivity of the hydraulic pressure is suddenly returned from the insensitive side to the set value (sensitive side) while the detection body is in contact with the field scene, hunting is induced and the posture of the work device is unstable. May be.

  In view of the above circumstances, an object of the present invention is to provide a working machine that does not induce hunting when the sensitivity of hydraulic pressure is returned from the insensitive side to a set value and that does not generate mud pushing or the like. .

In order to achieve the above object, the present invention according to claim 1 is directed to a traveling body (11) connected to a work device (31) to be movable up and down, and a sensing body (35) provided on the work device (31). In the work machine (10) for controlling the height of the work device (31) with respect to the ground based on the posture change by sensing the earth pressure of
Sensitivity adjusting means (41) for adjusting the earth pressure sensing sensitivity of the sensing body (35);
A control means (71) for desensitizing the sensitivity adjustment means (41) until the sensing body (35) is grounded, and slowly returning to the set sensitivity immediately after installation;
It is in the working machine equipped with.

In the present invention according to claim 2, the time from immediately after the grounding to the middle between the most insensitive and the set sensitivity is 1 to 2 [seconds].
The working machine according to claim 1.

In the present invention according to claim 3, the time from immediately after the grounding to the set sensitivity in a state where the set sensitivity is most sensitive is 2 to 4 [seconds].
The working machine according to claim 1.

  The reference numerals in the parentheses are for reference to the drawings and do not limit the present invention.

  According to the present invention, since the sensitivity is slowly returned to the set sensitivity after contact with the ground, hunting is not induced when the work apparatus is installed. For example, the intermediate position of the set sensitivity is 1 to 2 [seconds], and the most sensitive position is 2 to 4 Since the return time such as [second] is an appropriate time that is not so long, there is no problem in actual work such as mud pushing by the sensor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a side view of a working machine according to the present invention, FIG. 2 shows a front portion of a driver's seat of the working machine shown in FIG. 1, (a) is a plan view of an operation panel, and (b) is a hydraulic pressure. 3 is an enlarged view of the switching dial, FIG. 3 is a side view of the earth pressure detection sensitivity adjustment mechanism, FIG. 4 is a side view showing a state in which the earth pressure detection sensitivity adjustment mechanism is operated to the sensitive side, and FIG. FIG. 6 is a block diagram showing a control system of the work machine, FIG. 7 is a program flowchart showing a control procedure of hydraulic sensitivity, and FIG. 8 is a hydraulic sensitivity adjustment. FIG. 9 is a characteristic diagram showing a second example of the hydraulic pressure sensitivity adjustment process, FIG. 10 is a characteristic chart showing a third example of the hydraulic pressure sensitivity adjustment process, and FIG. FIG. 10 is a characteristic diagram showing a fourth example of the hydraulic pressure sensitivity adjustment process.

  As shown in FIG. 1, the work machine 10 includes a traveling machine body 11 and a work device 31 connected to the traveling machine body 11. The traveling machine body 11 includes a machine body 15 supported by front wheels 12 and a rear wheel 13, and an engine (not shown) is mounted on the front portion of the machine body 15 and is covered with a hood 16.

  A driver's seat 17 is installed at the center of the machine body 15, and a seat 18, a steering wheel 20 for driving operation, a shift lever 21 for shifting operation, a lifting operation of the working device 31, and an installation of a planting clutch.・ A quick-up lever 22 (see FIG. 2) for performing various operations such as a cutting operation and a left / right operation of a marker, various levers and pedals necessary for a driving operation, and an operation panel 23 in which various switches are disposed. Yes.

  As shown in FIG. 2, a hydraulic sensitivity switching dial 25 is arranged on the operation panel 23 in addition to various switches. As shown in FIG. 2 (b), the hydraulic sensitivity switching dial 25 can switch the hydraulic sensitivity to 11 levels from the most sensitive 1/11 to the most insensitive 11/11 according to the hardness of the field. It has become.

  As shown in FIG. 1, the working device 31 is detachably connected to the rear portion of the machine body 15 via an elevating link 26 whose one end swings up and down by the operation of a hydraulic cylinder 26. By the peristaltic motion of 26, the working device 31 moves up and down. Note that the power of the engine is transmitted to the working device 31 via a PTO shaft (not shown).

  The working device 31 is divided into a plurality of strips, a seedling platform 32 on which mat-shaped seedlings are placed, and a plurality of plants that scrape seedlings from the mat-shaped seedlings on the seedling platform 32 and plant them in a field. Attaching part 33 and a plurality of floats 35 are provided below the planting part 33 at predetermined intervals in the width direction of the seedling platform 32 and slide along the upper surface of the field. Of the plurality of floats 35, the float 35 located at the center also serves as a sensing body that senses the contact pressure (earth pressure) between the float 35 and the field top surface.

  As shown in FIG. 3, the float 35 (hereinafter referred to as the “sensing body 35”) that also serves as the sensing body is planted on a shaft 37 that is rotatably supported by the transmission case 36 of the working device 31. The arm 38 fixed integrally with the depth adjusting lever 40 is swingably supported.

  As shown in FIG. 3, the earth pressure detection sensitivity adjustment mechanism 41 that adjusts the earth pressure detection sensitivity of the detection body 35 drives a sector gear 43 that is swingably supported by a base 42, and the sector gear 43. A sensing wire motor 45 is provided, and one end of each of a posture adjusting wire 46 for adjusting the posture of the detection body 35 on the sector gear 43 and a detection wire 47 for adjusting a detection load of earth pressure detected by the detection body 35 is provided. It is connected. A sensing wire potentiometer 49 is disposed on the sector gear 43.

  The other end of the attitude adjusting wire 46 is connected to the tip of the detection body 35 via a sensing plate 48. Therefore, when the posture adjusting wire 46 is pulled forward (in FIG. 3, the right side of the paper surface) by the swing of the sector gear 43, the tip of the detection body 35 is pulled up. Further, when the posture adjusting wire 46 is pushed to the rear of the work machine 10 (left side of the paper surface in FIG. 3) by the swing of the sector gear 43, the tip of the detection body 35 is pushed down, and the detection body 35 postures can be adjusted.

  The other end of the detection wire 47 is linked to the planting depth adjustment lever 40 via a load spring 50, a linkage play 51, a linkage arm 52, and a linkage rod 53. The planting depth adjustment lever 40 and the sensing plate 48 are connected via a swing arm 55 and a return spring 56.

  Accordingly, when the detection wire 47 is pushed forward of the work machine 10 (in FIG. 3, the right side of the paper surface) by the swing of the sector gear 43, it acts in a direction to lower the rear portion of the sensing body 35. Further, when the detection wire 47 is pulled behind the working machine 10 by the swinging of the sector gear 43 (on the left side of the paper surface in FIG. 3), it acts in the direction of raising the rear part of the sensing body 35.

  As shown in FIG. 4, when the front end of the detection body 35 is in a posture that is lowered from the rear end, the pressure detection sensitivity can be made sensitive. As shown in FIG. If the part is in a posture raised from the rear end, the pressure detection sensitivity can be made insensitive.

  The hydraulic sensitivity adjustment mechanism 61 includes a hydraulic valve 62 disposed in front of the earth pressure detection sensitivity adjustment means 41 (on the right side in FIG. 3), the cooperative play 51, and a hydraulic valve arm 63 of the hydraulic valve 62. The detection load spring 65 is stretched between the two. Then, the hydraulic valve arm 63 is rotated, and the opening degree of the hydraulic valve 62 is opened.

  As shown in FIG. 6, the control means 71 of the work machine 10 is configured by a microcomputer 72, and the input section includes the hydraulic sensitivity switching dial 25, the engine rotation pulse 73, the pitching sensor 75, In addition to the lift angle potentiometer 76 that detects the lift angle of the lift link mechanism 27, various volumes and sensors necessary for the operation of the work machine 10 are connected. In addition to the sensing wire motor 45, various monitors, motors, alarm buzzers and the like necessary for operating the work machine 10 are connected to the output section of the microcomputer 72.

  The control procedure of the hydraulic pressure sensitivity with the above configuration will be described based on the program flowchart shown in FIG. Corresponding to the operation position of the planting depth adjustment lever 40, the position of the tip of the detection body 35, that is, the angle target value of the sector gear 43 is calculated (step S1, FIG. ).

  An engine rotation target value is calculated from the engine speed (step S2). That is, a value is calculated such that the basic posture of the detection body 35 rises forward as the engine speed increases. A sensing target value is set from the angle target value, the engine rotation target value, and the set value of the hydraulic pressure sensitivity switching dial 25 (step S3). A value is set such that the softer the field is, the lower the posture of the sensing body 35 is.

  When the set value of the hydraulic sensitivity switching dial 25 is on the sensitive side, the sensing target value is determined (step S4). When the set value of the hydraulic sensitivity switching dial 25 is in a position insensitive to 1/11 (the most sensitive position), the detection target value is set to 1/11 (step S5). When the set value of the hydraulic sensitivity switching dial 25 is on the insensitive side, the sensing target value is determined (step S6). When the set value of the hydraulic sensitivity setting dial is at a position more sensitive than 11/11 (the most insensitive position), the detection target value is set to 11/11 (step S7).

  The state of the work device 31 is determined (step S8). When the working device 31 is in the lowered position or the seedling planting state, it is determined whether or not the planting unit 33 is grounded (step S9).

  In addition, the planting part 33 is grounded by detecting the grounding of the detection body 35 to the field. That is, in the state where the planting part 33 is raised, the detection body 35 is in the front lowering state, and when the lowering command of the planting part 33 is given, the hydraulic valve 62 is switched to the automatic mode, and the detection body 35 is moved forward. The planting part 33 descends in the lowered state. When the planting portion 33 is lowered, the front portion of the detection body 35 comes into contact with the field, and when the planting portion 33 is further lowered, the detection body 35 rotates to raise the front portion. The rotation of the detection body 35 is transmitted to the hydraulic valve arm 63 via the sensing plate 48, the swing arm 55, the linkage rod 53, the linkage arm 52, the linkage play 51 and the sense load spring 65, as shown in FIG. Then, the opening degree of the hydraulic valve 62 is reduced, and the descending speed of the planting portion 33 is reduced. The descending speed of the planting unit 33 is detected by the lift angle potentiometer 76, and when the amount of change per unit time of the output falls below a certain level, it is detected as the grounding of the planting unit 33.

  When the working device 31 is in the raised position or fixed, or when the planting unit 33 is not installed, the sensing target value is set to 11/11 (step S10).

  It is determined whether there is an abnormality in the output of the sensing wire potentiometer 49 (step S11). If there is no abnormality in the output of the sensing wire potentiometer 49, the output cycle is determined (step S12). If the output cycle is 0, the deviation between the sensing target value and the sensing wire potentiometer output is calculated (step S13).

  When the calculated deviation is larger than the preset dead zone, the output ON time is calculated based on the deviation and a preset coefficient (step S15). An output cycle is set based on the calculated output ON time (step S16). At the same time, the drive direction flag is set (step S17).

  If the output of the sensing wire potentiometer 49 is abnormal in step S11, or if the deviation is smaller than the dead band in step S14, the output of the sensing wire motor 45 is stopped (step S18). At the same time, the drive direction flag is cleared (step S19).

  If the output cycle is not 0 in step S12, the output ON time is determined (step S20). If the output ON time is not 0, the drive direction flag (sensitive direction or insensitive direction) is determined (step S21). If the drive direction flag is 1/11 (sensitive direction), the sensing wire motor 45 is driven in the 1/11 direction (sensitive direction) (step S22). At the same time, the drive direction flag is set to 1/11 (sensitive direction) (step S23).

  If the driving direction flag is 11/11 (insensitive direction) in step S21, the sensing wire motor 45 is driven in 11/11 (insensitive direction) (step S24). At the same time, the drive direction flag is set to 11/11 (insensitive direction) (step S25). If the output ON time is 0 in step S20, the output of the sensing wire motor 45 is stopped (step S26).

  When the hydraulic sensitivity is adjusted according to the above procedure, the position of the detection wire 47 can be controlled in various ways as shown in FIGS.

  The control shown in FIG. 8 shows a case where the sensitivity value target value set to 8/11 is returned to the sensitivity of 1/11. After the detection body 35 is grounded, the return waiting time is 0, 5 seconds, It returns to the middle between the value 8/11 and the sensitivity 1/11 / in 1 second. Then, the detection sensitivity is returned to the detection sensitivity after 1 to 5 seconds from the grounding of the detection body 35.

  By adopting such control characteristics, hunting is not induced when the detection body 35 is grounded, and the return time is an appropriate time that is not so long, so that problems such as mud pushing by the detection body may occur. Can work without.

  The control shown in FIG. 9 shows a case where the detection target value is set to 11/11 and returned to the detection sensitivity of 1/11 so that the detection sensitivity becomes 1/11 3 seconds after the detection body 35 is grounded. Adjustment of the sense load adjusting wire 47 is started. The intermediate value 6/11 between the detection target value 11/11 and the detection sensitivity 1/11 is 1 to 5 seconds after the detection body 35 is grounded.

  By adopting such control characteristics, hunting is not induced when the detection body 35 is grounded, and the return time is an appropriate time that is not so long, so that problems such as mud pushing by the detection body may occur. Can work without. Also, the control can be simplified.

  The control shown in FIG. 10 shows a case where the detection target value is set to 11/11 and returned to the detection sensitivity of 1/11 so that the detection sensitivity becomes 1/11 3 seconds after the detection body 35 is grounded. The sensing load adjusting wire 47 adjusts the position of the sensing load adjusting wire 47 slowly for 1 and 5 seconds immediately after the start of adjustment, and the sensing value set after 3 seconds and the intermediate value 6/11 after 2 seconds. The sensitivity is set to 1/11.

  By adopting such control characteristics, it is possible to reliably prevent hunting induced by suddenly switching the sensing sensitivity when the sensing body 35 is grounded.

  The control shown in FIG. 11 shows a case where the detection target value is set to 11/11 and the detection sensitivity is returned to 1/11 so that the detection sensitivity becomes 1/11 3 seconds after the detector 35 is grounded. The sensing load adjusting wire 47 adjusts the position of the sensing load adjusting wire 47 so that the intermediate value becomes 6/11 in the first 1 second for 1 to 5 seconds immediately after the start of the adjustment, and then by 3 seconds. The sensitivity is adjusted slowly to 1/11.

  By adopting such control characteristics, the sensitivity can be close to 1/11 in a short time, mud pushing by the detection body 35 can be eliminated, and the work start timing can be advanced.

  The control characteristics are not limited to those exemplified above, but instead of switching the detection sensitivity at the moment when the detection body 35 contacts the field, it takes 1 to 2 seconds to the intermediate value and 2 to 4 seconds to the set sensitivity. In order to control slowly, it can set suitably according to the state of a field and the characteristic of the working machine 10. FIG.

It is a side view of the working machine which concerns on this invention. The front part of the driver's seat of the working machine shown in FIG. 1 is shown, (a) is a plan view of an operation panel, and (b) is an enlarged view of a hydraulic pressure switching dial. It is a side view of a soil pressure detection sensitivity adjustment mechanism. It is a side view which shows the state which operated the earth pressure detection sensitivity adjustment mechanism to the sensitive side. It is a side view which shows the state which operated the earth pressure detection sensitivity adjustment mechanism to the insensitive side. It is a block diagram which shows the control system of a working machine. It is a program flowchart which shows the control procedure of hydraulic pressure sensitivity. It is a characteristic view which shows the 1st example of hydraulic pressure sensitivity adjustment progress. It is a characteristic view which shows the 2nd example of hydraulic pressure sensitivity adjustment progress. FIG. 11 is a characteristic diagram illustrating a third example of the hydraulic pressure sensitivity adjustment process. It is a characteristic view which shows the 4th example of hydraulic pressure sensitivity adjustment progress.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Work machine 11 Traveling machine body 31 Work apparatus 35 Detection body (float)
71 Control means

Claims (3)

In the working machine that connects the working device to the traveling machine body so as to be movable up and down, and controls the ground height of the working device based on the posture change by the earth pressure sensing of the sensing body provided in the working device,
A sensitivity adjusting means for adjusting the earth pressure sensing sensitivity of the sensing body;
The sensitivity adjustment means, the control means to make the sensitivity most insensitive until the sensor is grounded, and to slowly return to the set sensitivity immediately after installation,
Work machine equipped with. The time from immediately after the grounding to the middle between the most insensitive and the set sensitivity is 1 to 2 [seconds].
The work machine according to claim 1. The time from immediately after the grounding to the set sensitivity in a state where the set sensitivity is most sensitive is 2 to 4 [seconds].
The work machine according to claim 1.

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