JP2008035752A - Rolling controller of agricultural working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out protection of an electric motor or a driver therefor from heat and protection thereof from an overload and to rapidly perform rolling control without a delay after reduction of the load in a rolling controller of an agricultural working machine composed so as to connect an implement to a traveling machine body for performing free driving and rolling with the electric motor, detect the tilt angle in the right and the left directions in the implement by a tilt detecting means, energize and operate the electric motor on the basis of the detected tilt angle and bring the right and left tilt angle of the implement close to the target tilt angle. <P>SOLUTION: The rolling controller of the agricultural working machine is composed so as to control a driving current of the electric motor 53 on the basis of a deviation of a detected tilt angle θ from the target tilt angle θ0 and is equipped with a load detecting means for detecting the driving load on the electric motor 53. A protecting means for controlling the driving current of the electric motor 53 is installed so as to maintain the detected driving load within the set range. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rolling control device used for farm work machines such as rice transplanters and agricultural tractors.

In a riding-type rice transplanter that is an example of a farm work machine, for example, as shown in Patent Document 1, a seedling planting device is connected to a rear portion of a traveling machine body as a working device so as to be capable of driving rolling, and an inclination angle of the seedling planting device. Based on the detection information, the energization control of the electric motor 14 for rolling is performed to stably maintain the tilt angle in the left-right direction of the seedling planting device 3 at the target tilt angle, and an intermediate that is forcibly rolled by the electric motor. A configuration in which the left and right rolling limit positions of the frame 11 are detected by limit switches 21R and 21L is known.
Japanese Patent Laid-Open No. 9-9748

  In a structure that detects the left and right rolling limit positions with a limit switch, etc., when it is detected that the rolling limit position has been reached, or when a current exceeding the set value has been detected in the electric motor, it is automatically sent to the electric motor. In general, the electric current is cut off, and the electric motor and its driver are protected against heat and overload. In this case, the energization of the electric motor is cut off, so that the holding force in the rolling direction is lost, and the rolling-driven work device (seed planting device) is tilted due to the loss of weight balance, and the load is reduced to reduce the rolling. There was a case that an operation delay occurs when the control is restored.

  The present invention has been made paying attention to such points, and is intended to provide thermal protection and overload protection for the electric motor and its driver, and to perform rolling control immediately after the load is reduced without delay. The purpose is to be.

According to a first aspect of the present invention, a work device is connected to a traveling machine body by an electric motor so as to be capable of being driven and rolled, and a tilt angle detecting means detects a tilt angle in the left-right direction of the work device and energizes the electric motor based on the detected tilt angle. A rolling control device for a farm machine configured to bring the right and left tilt angle of the work device closer to the target tilt angle,
The driving current of the electric motor is controlled based on the deviation between the detected inclination angle and the target inclination angle, and load detecting means for detecting the driving load of the electric motor is provided, and the detected driving load is within a set range. It is characterized by having a protection means for controlling energization of the electric motor so as to be maintained inside.

  According to the above configuration, when it is detected that the driving load of the electric motor has reached the limit of the setting range, for example, the rolling operation resistance of the work device is increased, a current greater than the current amount is supplied to the electric motor. The driving current of the electric motor is suppressed and controlled so that the driving load of the electric motor is not deviated from the set range. In other words, the electric motor continues to be supplied with drive power, and does not enter the free rolling state as when the power supply is cut off. It will never tilt.

  When it is detected that the driving load has been reduced and returned to the set range, the normal control state is restored, and the electric motor is energized and controlled with the amount of current determined based on the detected inclination angle. The inclination angle is quickly brought close to the target inclination angle.

  Therefore, according to the first aspect of the present invention, the work device is not tilted spontaneously by cutting off the power supply while protecting the electric motor and its driver against heat and overload. After that, the rolling control can be performed promptly without delay.

According to a second invention, in the first invention,
The drive current of the electric motor is configured to perform duty control, and includes a sensor that detects an operating position of a rolling drive member that is operated by the electric motor, and a drive output duty that controls the drive current of the electric motor and the rolling drive member The load detecting means is configured to estimate the driving load of the electric motor based on the position fluctuation.

  According to the above configuration, the smaller the position fluctuation speed of the rolling drive member with respect to a certain amount of current, the greater the driving load. The drive load of the electric motor can be estimated by comparison based on the input map data and the like. In this case, the position of the rolling drive member can be easily detected by an inexpensive sensor such as a potentiometer. Therefore, an overload can be prevented by acquiring the drive load of the electric motor with an inexpensive configuration that does not use a load detection sensor such as a torque sensor. The suitable energization control can be performed.

According to a third invention, in the second invention,
The operation range of the rolling drive member is set, and when the sensor detects that the rolling drive member has reached the limit of the operation range, the rolling drive member is issued until a rolling operation command is issued to return the operation range to the operation range. Is configured to control the energization of the electric motor so as to be maintained at the limit position.

  According to the above configuration, the operating range of the rolling drive member can be limited by using the position information of the rolling drive member as data for estimating the drive load, and a limit switch for determining the operating range of the rolling drive member becomes unnecessary. Therefore, the number of sensors can be reduced and implemented at low cost.

4th invention is the said 2nd or 3rd invention,
The maximum value of the drive output duty is limited.

  According to the above configuration, as the deviation between the detected tilt angle and the target tilt angle increases, the drive output duty increases to increase the amount of current to the electric motor, but the maximum value of the drive output duty is limited. As a result, an excessive current is not applied to the electric motor, and the electric motor and its driver can be protected from heat.

  FIG. 1 shows a side view of a riding type rice transplanter with a fertilizer device as an example of a farm working machine according to the present invention, and FIG. 2 shows a plan view thereof. This riding type rice transplanter has a front-wheel 1 and a rear-wheel 2 and a seedling of an eight-row planting specification via a link mechanism 4 having a parallel quadruple link structure at the rear of a traveling machine body 3 configured to be capable of four-wheel drive traveling. A planting device (working device) 5 is connected to be movable up and down, a fertilizer device 6 is provided at the rear of the machine body, and a structure is provided with reserve seedling platforms 7 on the left and right of the front part of the machine body. The seedling planting device 5 can be controlled to move up and down by driving and swinging up and down by the hydraulic cylinder 8. The seedling planting device 5 is connected to the rear end portion of the link mechanism 4 so as to be capable of rolling around the fulcrum X in the front-rear direction, and the seedling planting device 5 is described later by a rolling drive mechanism 9 provided at the upper rear end of the link mechanism 4. So that it is rolling controlled.

  An engine 10 is mounted on the front of the traveling body 3, and its output is transmitted to a hydraulic continuously variable transmission (HST) 11 capable of forward / reverse continuously variable transmission, and the transmission output is input to the mission case 12. Then, after being gear-shifted by a sub-transmission device (not shown), it is transmitted to the left and right front wheels 1 supported by the mission case 12, and the traveling system power taken rearward from the mission case 12 is transmitted via the transmission shaft 13. It is transmitted to the rear transmission case 14 and is transmitted to the left and right rear wheels 2 supported by the rear transmission case 14. After the forward rotation power of the shift output transmitted from the hydraulic continuously variable transmission 11 to the transmission case 12 is branched as working power, and gear-shifted by a stock transmission (not shown) incorporated in the transmission case 12, It is taken out from the rear of the mission case 12 and transmitted to the seedling planting device 5 via the transmission shaft 15 and the telescopic transmission shaft 16.

  As shown in FIGS. 2 and 3, the seedling planting device 5 includes a horizontally long rectangular tubular planting frame 21, a feed case 22 that receives working power taken out from the traveling machine body 3, and a reciprocating lateral movement left and right with a constant stroke. The seedling platform 23, eight sets of rotary planting mechanisms 24, four planting cases 25 provided with two planting mechanisms 24 on the left and right of the rear, and the planting location of the rice field T are leveled. Five leveling floats 26 are provided.

  The central one of the five leveling floats 26 arranged in parallel is used as a ground contact sensor SF that detects the height of the seedling planting device 5 with respect to the field surface T. As shown in FIG. 5, the vertical swinging displacement around the rear portion fulcrum q of the ground sensor SF is electrically detected by the potentiometer 27, and the detected information is input to the control device 28 for arithmetic processing, and the ground sensor SF. By operating the electromagnetic control valve 29 that controls the operation of the hydraulic cylinder 8 so that the vertical swinging position of the seedling becomes the set posture, the height of the seedling planting device 5 with respect to the field surface T is maintained constant, and planting Automatic planting depth control is performed to maintain the depth stably.

  As shown in FIG. 4, the rolling drive mechanism 9 includes a rolling drive member 51 supported on a bracket 50 connected to the upper rear end of the link mechanism 4 so as to be able to swing left and right around a fulcrum fulcrum a and a gear reduction mechanism. An electric motor 53 that swings through a mechanism 52 is configured. As shown in FIG. 3, a support frame 55 is laid across the upper ends of columns 54 erected from the left and right of the planting frame 21, and guide members 56 mounted on the left and right portions of the support frame 55 are used as seedlings. The upper part of the seedling base 23 is engaged and guided so as to be movable in the left-right direction by being engaged with a guide rail 57 horizontally connected to the back portion of the mounting base 23 as a reinforcing frame. The upper free end portion of the rolling drive member 51 and the left and right portions of the support frame 55 are connected via an accommodation spring 58.

  According to this configuration, the seedling planting device 5 is elastically supported by the rolling drive member 51 via the interchange spring 58 so that it can freely roll in a predetermined small range, and the seedling planting device 5 is supported via the leveling float 26. In a state where the ground plane T is in contact with the ground surface T, the seedling planting device 5 follows the ground surface T within the range of elastic accommodation even if the traveling machine body 3 is slightly inclined to the left and right.

  The electric motor 53 of the rolling drive mechanism 9 is controlled to operate based on detection information from an inclination angle detection means (described later) installed in the seedling planting device 5, and the traveling machine body 3 is inclined to the left and right by unevenness of the tillage board. Even if the seedling planting device 5 is about to tilt, the seedling planting device 5 is controlled to roll in a direction to restore the tilting, and is always stably maintained in the set rolling posture (generally horizontal). Planting with little difference in depth has been carried out. When the swinging position of the rolling drive member 51 is detected by the potentiometer 60 and the rolling drive member 51 reaches the set swinging position, the electric motor 53 is energized and controlled so that the swinging position is maintained. The swing range of the rolling drive member 51 is limited.

  A return spring 59 is stretched across the bracket 50 connected to the upper rear end of the link mechanism 4 and the left and right portions of the guide rail 57 on the rear surface of the seedling platform 23, and the lateral movement of the seedling platform 23. As a result, the return spring 59 on the moving direction side is extended, so that the rotational force in the direction to correct the collapse of the weight balance around the fulcrum X for rolling accompanying the lateral movement of the seedling bed is caused by the extended return spring 59. Has come to be brought.

  As means for detecting the lateral inclination angle of the seedling planting device 5, a gravity type angle sensor 61 and a vibrating gyroscopic angular velocity sensor 62 for detecting the angular velocity in the lateral direction are used, and a fulcrum X for rolling is used. It is attached to the planting frame 21 in the vicinity. As shown in the control block diagram of FIG. 6, the detection signals from both sensors 61 and 62 are input to the control device 28, and the detected inclination angle θ for rolling control of the seedling planting device 5 is calculated as follows. And rolling control is executed.

  The detected value θg of the angle sensor 61 is passed through the low-pass filter 63 to obtain only its low frequency component, and the detected value e of the angular velocity sensor 62 is subjected to integration processing after passing through the low-cut filter 64 and is then tilted. The angle is calculated, and the calculated value is further passed through the low-cut filter 65 to acquire only the high-frequency component. Next, the inclination angle θ1 of the low-frequency component acquired based on the detected value θg of the angle sensor 61, and the angular velocity The inclination angle θ2 of the high-frequency component acquired based on the detection value e from the sensor 62 is added, and this value is set as the detection inclination angle θ.

  Note that the detected value θg from the angle sensor 61 has a part of the high-frequency component of the detection signal removed together with the disturbance due to the smoothness characteristic of the gravity sensor itself. Therefore, in order to compensate for this removed high-frequency component, A low cut filter 64 having characteristics corresponding to the characteristics is introduced. Further, the characteristics of the low cut filter 65 are set so as to compensate for the high frequency components removed by the low pass filter 63.

  That is, when the seedling planting device 5 is rapidly tilted, the detected value θg from the angle sensor 61 includes disturbance due to vibration and the like, and a signal in the reverse direction may be output due to the influence of inertia. A value obtained by removing the high frequency component included is acquired as the basic inclination angle θ1. Then, in order to compensate for the high-frequency component from which the inclination angle fluctuation has been removed, the inclination angle θ2 of the high-frequency component calculated and acquired based on the detection value e of the angular velocity sensor 62 is added, and the overall response is excellent and the accuracy is high. The detected inclination angle θ is calculated.

  The detected tilt angle θ calculated as described above is compared with the target tilt angle θ0 set by the tilt angle setting unit 66, and the deviation | θ0−θ | between the two is calculated based on the dead zone ε set in advance. If it is larger, the electric motor 53 is energized and controlled so that the deviation falls within the dead zone, so that the seedling planting device 5 is stably maintained at the target inclination angle θ0.

  Since most of the rice field T is horizontal in the rice transplanter, the seedling planting device 5 is maintained in a horizontal posture parallel to the rice field T by setting the target inclination angle θ0 to be horizontal. Although the planting depth can be made uniform, in the planting operation at the paddy field where the field surface T is tilted to the left and right at the paddy field, the target tilt angle θ0 is adjusted by adjusting the tilt angle setting unit 66. Is adjusted in accordance with the inclination of the field surface T, so that the planting depth can be made uniform by performing planting parallel to the inclined field surface T.

  The driver 70 of the electric motor 53 is configured to duty-control the drive current of the electric motor 53 based on a command from the control device 28. As shown in the flowchart of FIG. 7, the drive output duty D is calculated according to the magnitude of the deviation | θ0−θ | between the detected inclination angle θ and the target inclination angle θ0 calculated as described above (# 01, # 02), the greater the drive output duty D, the greater the amount of current flowing through the electric motor 53. However, the maximum value of the drive output duty D is set in advance so that an excessive current does not flow through the electric motor 53 and the driver 70.

  The drive load (load torque) of the electric motor 53 is estimated from the fluctuation speed of the detected value from the potentiometer 60 with respect to the calculated drive output duty D (# 03). That is, the driving load increases as the moving speed of the rolling driving member 51 decreases in driving with a certain amount of current, and the fluctuation speed of the detected value from the potentiometer 60 and the driving output duty D are compared based on the map data. Thus, the driving load of the electric motor 53 is estimated.

  It is determined whether or not the estimated driving load is within a preset allowable range (# 04). When the limit of the allowable range is reached, the deviation | θ0−θ | between the target inclination angle θ0 and the detected inclination angle θ The electric motor 53 is energized and controlled with the drive output duty D ′ that maintains the limit value of the drive load in preference to the drive output duty D calculated in accordance with the magnitude of (# 05, # 06). When it is recognized that the estimated driving load has fallen below a predetermined amount (hysteresis amount) from the limit of the allowable range (# 07), the deviation | θ0−θ | of the target inclination angle θ0 and the detected inclination angle θ is large. Returning to the normal control state in which the electric motor 53 is energized with the drive output duty D calculated accordingly.

  As shown in the flowchart of FIG. 8, when the rolling drive member 51 reaches the left or right limit in the preset operating range, this is detected based on information from the potentiometer 60 and is within the operating range. The electric motor 53 is energized to maintain the rolling drive member 51 at the limit position until a rolling operation command in the returning direction is issued.

  As shown in the flowchart of FIG. 9, when the seedling planting device 5 that has been raised to the upper limit is lowered to the surface T, the rolling control is immediately executed even if the descent command is issued by the operator and the descent is started. The rolling drive member 51 is maintained at the lowering start position until the contact of the ground sensor SF with the surface T is detected by the output change of the potentiometer 27, and the seedling planting device 5 is at the lowering start time. It is lowered while maintaining the posture. When the ground sensor SF comes into contact with the rice field T and an output change occurs in the potentiometer 27, it is determined that the seedling planting device 5 is grounded, and thereafter normal rolling control is performed.

  When the seedling planting device 5 is forcibly raised based on the ascent command issued by the operator, such as when turning the aircraft at the shore, the link mechanism 4 rises to the upper limit and the upper limit switch 30 is turned on. Rolling control is executed until the seedling planting device 5 is maintained in a horizontal posture even if the right and left weight balance of the seedling planting device 5 is lost due to the consumption of seedlings placed on the seedling table 23, etc. Will be. When it is detected by the upper limit switch 30 that the upper limit has been reached, the control valve 29 is automatically neutrally controlled to stop the raising of the seedling planting device 5 and the rolling control is also stopped. In addition, the seedling planting device 5 that has reached the upper limit is mechanically fixed in a posture parallel to the traveling machine body 3 by contact with the link mechanism 4, and is prevented from rolling freely during traveling.

[Other Examples]
(1) As a means for detecting the driving load of the electric motor 53, a torque sensor can be provided on the output shaft of the electric motor 53 and the driving load torque can be directly detected.
(3) In addition to the riding-type rice transplanter, the present invention is a farming machine in which working devices such as a paddy direct sowing device and a paddy weeding device are connected to a traveling machine body so as to be able to move up and down freely and a rotary tiller device can be raised and lowered freely. It can also be applied to agricultural tractors connected to the

Whole side view of rice transplanter Overall plan view of rice transplanter Rear view of the seedling planting device as seen from the front Vertical side view of rolling drive mechanism Block diagram showing the outline of the entire control system Block diagram of rolling control system Rolling control system flow diagram Flow chart of rolling limit control Flow chart showing operations related to lifting and rolling control

Explanation of symbols

1 traveling machine 3 working device (seedling planting device)
51 Rolling drive member 53 Electric motor θ0 Target tilt angle D Drive output duty θ Detection tilt angle

Claims (4)

A work device is connected to the traveling machine body by an electric motor so as to be capable of being driven and rolled, a tilt angle detecting means detects a tilt angle in the left-right direction of the work device, and energizes the electric motor on the basis of the detected tilt angle. A rolling control device for a farm machine configured to bring the right and left tilt angle closer to the target tilt angle,
The driving current of the electric motor is controlled based on the deviation between the detected inclination angle and the target inclination angle, and load detecting means for detecting the driving load of the electric motor is provided, and the detected driving load is within a set range. A rolling control device for a farm working machine, comprising a protection means for controlling energization of an electric motor so as to be maintained inside.   The drive current of the electric motor is configured to perform duty control, and includes a sensor that detects an operating position of a rolling drive member that is operated by the electric motor, and a drive output duty that controls the drive current of the electric motor and the rolling drive member The rolling control device for an agricultural working machine according to claim 1, wherein the load detecting means is configured to estimate a driving load of the electric motor based on a positional fluctuation of the agricultural machine.   The operation range of the rolling drive member is set, and when the sensor detects that the rolling drive member has reached the limit of the operation range, the rolling drive member is issued until a rolling operation command is issued to return the operation range to the operation range. The rolling control device for an agricultural working machine according to claim 2, wherein the electric motor is energized and controlled so as to maintain the position at a limit position.   The rolling control device for an agricultural machine according to claim 2 or 3, wherein a maximum value of the drive output duty is limited.

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