JP2022044618A - Work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a self-propelled chemical sprayer for improving the convenience and safety of a vibration damping mechanism of a spray boom.

SOLUTION: A self-propelled chemical sprayer includes a travel vehicle body A, an operation part, a chemical spray part b1 configured to be liftable/lowerable by extending or shortening a lifting/lowering cylinder, an accumulator U connected to the lifting/lowering cylinder, an on-off valve for opening/closing a passageway for communicating both, and a control part configured to be controllable over the extending or shortening of the lifting/lowering cylinder and the opening/closing of the on-off valve. The operation part is provided with a key switch for powering on the self-propelled chemical sprayer, and the control part performs opening control of the on-off valve with the on of the key switch as a condition, and further performs closing control of the on-off valve with the off of the key switch as a condition.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to a self-propelled drug sprayer for spraying a drug.

Conventionally, there is known a self-propelled chemical sprayer equipped with a chemical spraying device provided with a spraying boom for spraying and spraying a chemical such as a pest control liquid on the front portion of a traveling vehicle body.

For example, Patent Document 1 discloses a self-propelled drug sprayer in which an elevating frame is provided on an elevating link that moves up and down by extending or shortening the elevating cylinder, and a spraying boom is attached to the elevating frame.

Here, since one end of the spray boom is supported by the traveling vehicle body and the other end is cantilevered so as to be a free end, when the traveling vehicle body vibrates due to the unevenness of the field during work, the vibration is generated. It is transmitted to the spray boom and vibrates violently. As a result, the spraying of the chemicals becomes uneven, which leads to a decrease in work efficiency and chemical spraying efficiency. Therefore, it has been a conventional problem to suppress the vibration of the spraying boom.

Therefore, in Patent Document 2, by connecting an accumulator that absorbs pressure fluctuations in the elevating cylinder to the elevating cylinder, the accumulator exerts a spring action on the elevating cylinder, thereby reducing vibration of the elevating frame. , A technique for suppressing the vibration of the spray boom during work is disclosed. Further, in Patent Document 3, an on-off valve is provided in the supply / discharge passage of the hydraulic oil between the elevating cylinder and the accumulator, and when the elevating frame moves up and down, the on-off valve is closed to cover the hydraulic oil between the elevating cylinder and the accumulator. Disclosed is a technique for temporarily shutting off supply and discharge, thereby improving the responsiveness to the raising and lowering operation of the spray boom.

Japanese Unexamined Patent Publication No. 2019-17310 Japanese Unexamined Patent Publication No. 2013-102 Japanese Unexamined Patent Publication No. 2017-23041

Here, according to the self-propelled chemical sprayer to which the prior art disclosed in Patent Document 2 and Patent Document 3 is applied, when the accumulator absorbs the pressure fluctuation in the elevating cylinder and exerts a spring action, it self-propells. The spray boom is not fixed to the traveling vehicle body of the accumulator, and can swing up and down.

However, when not working, it may be desirable to turn off the spring action of the accumulator and fix the spray boom to the traveling vehicle body. For example, when the spraying boom is swingable up and down, such as when transporting a self-propelled chemical sprayer, there is a risk of contact with an external obstacle due to the swing. Therefore, in such a case, conventionally, it is inconvenient for the operator to manually close the on-off valve provided in the hydraulic oil supply / discharge passage between the elevating cylinder and the accumulator. In addition, after closing the on-off valve, there is a risk that the operator may forget to open it again during work.

Further, during the elevating operation of the spray boom, the on-off valve provided in the hydraulic oil supply / discharge passage between the elevating cylinder and the accumulator is closed, and the on-off valve is opened after the elevating operation of the spray boom is completed and stopped. According to this, when the on-off valve is opened, the hydraulic oil rapidly flows from the elevating cylinder to the accumulator side due to the pressure difference between the elevating cylinder and the accumulator, and as a result, the elevating cylinder is rapidly shortened and the spray boom. Has a problem that the operation becomes unstable because it descends from the stop position.

As described above, the conventional self-propelled chemical sprayer has room for improvement in terms of convenience and stability in the vibration damping function of the spray boom using an accumulator. Therefore, the present invention solves such a conventional problem by providing a self-propelled chemical sprayer that improves the convenience and safety of the vibration damping function of the spray boom using an accumulator. The purpose is.

In order to achieve the above object, the invention of claim 1 is to move up and down by extending or shortening a traveling vehicle body (A) for traveling the machine body, an operation unit (a6) for receiving an operator's operation, and an elevating cylinder (b21). An accumulator (U) that is connected to the elevating cylinder (b21) and stores a pressurized working fluid, and the elevating cylinder (b21) and the accumulator (U) that are configured so as to be able to spray the medicine. The on-off valve (u1) that opens and closes the passage that communicates with the above, and the operation information of the operation unit (a6) can be acquired. A self-propelled drug sprayer comprising a control unit (C) configured to be able to control the above, wherein the operation unit (a6) includes a key switch for turning on the power of the self-propelled drug sprayer. The control unit (C) opens and controls the on-off valve (u1) on condition that the key switch is operated and the power of the self-propelled drug sprayer is turned on, and the key switch is further operated. It is characterized in that the on-off valve (u1) is closed and controlled on condition that the power of the self-propelled chemical sprayer is turned off.

The invention of claim 2 is the self-propelled drug sprayer according to claim 1, wherein the control unit (C) is operated to extend or contract the elevating cylinder (b21) in the operation unit (a6). Then, the on-off valve (u1) is controlled to be closed and then opened for a predetermined set time (t), and the set time (t) is within the range of 0.5 seconds to 1 second. It is characterized by being.

The invention of claim 3 is characterized in that, in the self-propelled drug sprayer according to claim 2, the set time (t) can be adjusted by operating the operation unit (a6).

According to the first aspect of the present invention, the control unit opens and controls the on-off valve on condition that the key switch is operated to turn on the power of the self-propelled drug sprayer, and further, the key switch is further controlled. Is operated to control the closing of the on-off valve on condition that the power of the self-propelled drug sprayer is turned off. In this way, according to the configuration in which the on-off valve is opened and closed in conjunction with the on / off operation of the key switch by the operator, the on-off valve is surely opened when the engine is stopped, the engine is running, or when the engine is working with only the power turned on. Therefore, unlike the conventional case, the labor of the operator to open the on-off valve by manual operation is omitted, and the convenience is improved. Furthermore, during non-working, the vibration damping function by the accumulator is automatically turned off in conjunction with the key switch off, so that the spraying boom is performed during non-working, for example, when transporting a self-propelled drug sprayer. Can be prevented from swinging up and down and coming into contact with external obstacles, improving safety.

According to the second aspect of the present invention, in addition to the effect of the invention according to the first aspect, while ensuring good responsiveness during the raising / lowering operation of the spraying boom, even during the raising / lowering operation of the spraying boom after the start of raising / lowering. , The vibration damping function of the accumulator can be exerted well, the spray boom can be raised and lowered smoothly, and the operation of the spray boom is stable.

According to the invention of claim 3, in addition to the effect of the invention of claim 2, it is possible to meet detailed needs for the weight of the spray boom and the responsiveness of the operator.

It is a perspective view of the self-propelled drug sprayer which concerns on a preferable embodiment of this invention. It is a left side view of the self-propelled chemical sprayer of FIG. It is a top view of the self-propelled chemical sprayer of FIG. It is a front view of the self-propelled chemical sprayer of FIG. It is a circuit diagram which shows a part of the hydraulic circuit of the self-propelled chemical sprayer of FIG. It is an enlarged view of the front main part of the self-propelled chemical sprayer of FIG. It is a flowchart which shows the control procedure by the controller of FIG. It is a flowchart which shows the procedure by the controller of the spraying boom elevating process of FIG. It is a time chart which shows the operation of the accumulator of FIG. It is a front view of the self-propelled drug sprayer which concerns on another embodiment of this invention. It is a circuit diagram which shows a part of the hydraulic circuit of the self-propelled chemical sprayer of FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the embodiment, the left-right direction is referred to as left and right, the forward direction is referred to as forward, and the reverse direction is referred to as rear toward the forward direction of the aircraft, but the configuration of the present invention is not limited.
(overall structure)
An example of the overall configuration of the self-propelled chemical sprayer 1 will be specifically described.

As shown in a perspective view in FIG. 1, a left side view in FIG. 2, a plan view in FIG. 3, and a front view in FIG. 4, the self-propelled chemical sprayer 1 has a self-propelled traveling vehicle body A and its traveling. It is configured to include a cabin K provided on the vehicle body A, a drug tank M for storing the drug, and a drug spraying device B having a spray boom b1 for spraying the drug supplied from the drug tank M to the field. ing.

The traveling vehicle body A includes a main frame a1, a driver's seat a2, a steering handle a3, a front wheel a4, and a rear wheel a5. The main frame a1 is formed so as to extend to the front and rear of the traveling vehicle body A. The driver's seat a2 is a seat for the operator to sit down when operating the passenger control device 1. At an appropriate position around the driver's seat a2, an operation panel a6 having an operation switch, a key switch, or the like for controlling operations such as opening / closing of the spray boom b1 and spraying of a drug is arranged.

The steering handle a3 standing in front of the driver's seat a2 changes the traveling direction of the self-propelled chemical sprayer 1 by steering at least the left and right front wheels a4 and a4 by a rotation operation by the operator. That is, the front wheels a4 and a4 are steering wheels that are steered by at least the rotation operation of the steering handle a3.

In the front wheels a4 and the rear wheels a5, the power of the engine in the bonnet a7 is appropriately changed in the transmission case (not shown), and the changed power is transmitted to drive the engine to rotate.

The cabin K forms a passenger compartment by surrounding the driver's seat a2 and surrounding equipment, steering wheel, and the like. The cabin K is arranged between the medicine tank M and the spray boom b1. The cabin K is composed of a cabin frame k1, a cabin roof k2, left and right opening / closing doors k3L, k3R, and the like.

The drug tank M is a container for storing the drug. As shown in FIG. 3 in a plan view, the medicine tank M is arranged on the rear side of the cabin K, is formed in a U shape so as to surround the left and right sides and the rear side of the driver's seat a2, and is formed in a U shape. It is mounted on a1 so that it can be attached and detached. The chemicals stored in the chemical tank M are liquids such as fertilizers, pesticides and the like dissolved in a solvent (for example, water), and liquids containing solids such as fertilizers and pesticides (for example, water). Is.

(Drug spraying device)
The chemical spraying device B includes a spraying boom b1 for spraying in the field and a support device b2 for supporting the spraying boom b1 on the traveling vehicle body A.

The spray boom b1 is composed of a center boom b1F located in front of the traveling vehicle body 2 and side booms b1L and b1R located on both sides.

The center boom b1F extends horizontally in the vehicle width direction of the traveling vehicle body 2. Further, a plurality of nozzles bn for injecting a drug in a mist form are arranged on the center boom b1F at intervals.

The side booms b1L and b1R are rotatably arranged on both the left and right sides of the center boom b1F. A plurality of nozzles bn for spraying the medicine in a mist form are arranged on the side booms b1L and b1R at intervals. Due to the rotation of the side booms b1L and b1R, the spray boom b1 has a spraying posture in which the entire body is substantially linear so as to extend in the vehicle width direction (left-right direction) of the traveling vehicle body A, and the side booms b1L and b1R are traveling vehicle bodies 2. It is possible to switch to the storage posture along the left and right sides of. The spraying boom b1 configured in this way can widely spray the drug on the left and right sides of the front side of the self-propelled drug sprayer 1 in the spraying posture.

As shown in FIGS. 2 and 3, the support device b2 is a device that supports the spray boom b1 on the traveling vehicle body A so as to be able to move up and down, and has a lift link b20 that rotates by extending or shortening the lift cylinder b21 and a lift link b20. The mounting frame b21 connected to the front end of the link b20, the lifting frame b23 mounted on the mounting frame b22 and moved up and down by the rotation of the lifting link b20, and the side booms b1L and b1R on both sides are rotated substantially horizontally. It is configured to include opening / closing cylinders b24 and b24 that open and close. As shown in FIG. 4, the mounting frame b22 has a rectangular frame shape when viewed from the front, and the elevating frame b23 is rotatably pivoted about the rolling shaft Y by the rolling shaft Y provided at the lower part. It is configured to support.

A center boom b1 (b1F) is attached to the front part of the elevating frame b23, and side booms b1L and b1R are rotatably attached to both left and right sides of the elevating frame b23 so that they can be deployed in the vehicle width direction. There is. With such a configuration, when the elevating frame b23 moves up and down, the spray boom b1 also moves up and down.

The opening / closing cylinders b24 and b24 can be switched between a spraying posture extending in the vehicle width direction of the traveling vehicle body A and a storage posture along the left and right sides of the traveling vehicle body A by extending or shortening, and the elevating frame b23 and the side. It is connected to the booms b1L and b1R, and is configured to rotate the side booms b1L and b1R on both sides when the opening / closing cylinders b24 and b24 are extended or shortened. Further, the expansion or contraction of the opening / closing cylinders b24 and b24 is controlled by the controller C described later.

(Spraying boom damping device)
As shown in FIG. 4, an accumulator U that absorbs pressure fluctuations in the elevating cylinder b24 is mounted on the elevating frame b23.

FIG. 5 is a circuit diagram showing a part of the hydraulic circuit of the self-propelled chemical sprayer 1.

As shown in FIG. 5, the vibration damping mechanism of the spray boom b1 is the accumulator U, the on-off valve u1 provided in the hydraulic oil supply / discharge passage connecting the elevating cylinder b21 and the accumulator U, and the on-off valve u1. It is configured to include a controller C capable of controlling opening and closing.

The first and second pumps P1 and P2, which are hydraulic pumps, are composed of fixed-capacity gear pumps driven by the power of an engine. The discharge oil passage 100 for circulating the hydraulic oil discharged from the first and second pumps P1 and P2 is connected to the first constant flow valve u2 that divides a constant flow rate. The first constant flow valve u2 is connected to the second constant flow valve u3 by the first oil passage 101. The second constant flow valve u3 is connected to a discharge oil passage 100a for circulating the discharge oil (pilot oil) discharged from the third pump P3. , Is connected to the vertical movement switching valve u4 by the second oil passage 102.

The vertical movement switching valve u4 is an electromagnetic switching valve that stops the extension position u41 as an operating position for extending the elevating cylinder b21, the contraction position u42 as the operating position for contracting the elevating cylinder b21, and the elevating cylinder b24. It is possible to switch to the stop position u43.

The vertical movement switching valve u4 includes a second oil passage 102, a third oil passage 103 communicating with the left and right elevating cylinders b21 and b21 and an on-off valve u1, and a discharge oil passage 104 for returning hydraulic oil to the hydraulic oil tank T. It is connected. A relief valve u5 is provided between the second oil passage 102 and the discharge oil passage 104, and is opened when the oil pressure of the second oil passage 102 exceeds the set value, and the oil pressure is supplied to the discharge oil passage 104. Is designed to escape.

When the vertical movement switching valve u4 is switched to the extension position u41, the second oil passage 102 and the third oil passage 103 communicate with each other, so that the hydraulic oil discharged from the first and second pumps P1 and P2 is discharged oil. It flows into the piston side chambers b211 and b211 of the elevating cylinders b21 and b21 through the passage 100, the first oil passage 101, the second oil passage 102 and the third oil passage 103. As a result, the elevating cylinders b21 and b21 extend, so that the elevating link b20 is rotated upward and the elevating frame b23 moves upward, and the spray boom b1 rises with respect to the traveling vehicle body 2 together with the elevating frame. ..

When the vertical movement switching valve u4 is switched to the contraction position u42, the discharge oil passage 104 and the third oil passage 103 are communicated with each other. As a result, the hydraulic oil in the piston side chambers b211 and b211 of the elevating cylinders b21 and b21 is returned to the hydraulic oil tank T through the third oil passage 103 and the discharge oil passage 104. As a result, the elevating cylinder b21 contracts, so that the elevating link b20 is rotated downward and the elevating frame b23 moves downward, and the spray boom b1 descends with respect to the traveling vehicle body A together with the elevating frame b23.

When the vertical movement switching valve u4 is switched to the stop position u43, the third oil passage 103 is closed. As a result, the hydraulic oil entering and exiting the piston side chambers b211 and b211 through the third oil passage 103 is blocked, and the height of the spray boom b1 with respect to the traveling vehicle body A is maintained.

The on-off valve u1 is an electromagnetic switching valve, and can switch between a communication position u11 that communicates with the piston side chamber b211 of the elevating cylinder b21 and the accumulator U, and a shutoff position u12 that cuts off the communication.

When the on-off valve u1 is switched to the communication position u11 (opening control of the on-off valve u1), the third oil passage 103 and the accumulator U communicate with each other, whereby the piston side chamber b211 of the elevating cylinder b21 and the accumulator U communicate with each other. .. As a result, the accumulator U absorbs the pressure fluctuation in the elevating cylinder b21 and exerts a spring action by the hydraulic oil moving back and forth between the two, so that the vibration of the spray boom b1 is suppressed and the vibration damping function is exhibited. ..

When the on-off valve u1 is switched to the shutoff position u12 (close control of the on-off valve u1), the communication between the third oil passage 103 and the accumulator U is cut off, whereby the piston side chamber b211 of the elevating cylinder b21 and the accumulator U Communication is cut off. As a result, the vibration damping function of the accumulator U can be stopped, and the responsiveness when raising and lowering the spray boom b1 can be improved. In addition, the responsiveness specifically refers to the quickness from the operation of the boom up switch or the boom down switch to the start of the up / down operation of the spray boom b1.

The controller C is a control device capable of controlling the vertical movement switching valve u4 and the on-off valve u1, and includes a CPU, a ROM, a RAM, and the like, and stores a predetermined control program. Further, the vertical movement switching valve u4 and the on-off valve u1 are electrically connected to the controller C, and the positions can be switched by being controlled by the controller C. The controller C may be configured so that the positions of the vertical movement switching valve u4 and the on-off valve u1 can be controlled by using a timer, a relay, or the like without using a CPU, ROM, RAM, or the like.

The controller C is electrically connected to the operation panel a6, and can acquire the operation of various operation switches provided on the operation panel a6 as a signal. That is, it is possible to acquire the operation information of the operation panel a6 by the operator. The operation panel a6 has at least a boom rise switch (not shown) operated when raising the spray boom b1 with respect to the traveling vehicle body A and a boom lowering operated when raising the spray boom b1 with respect to the traveling vehicle body A. A switch and a key switch operated when the power of the self-propelled chemical sprayer 1 is turned on are provided. The key switch is an operation switch that can be switched on and off, and it is a condition for the engine of the self-propelled chemical sprayer 1 that the key switch is in the on state. Therefore, the operator can operate the engine of the self-propelled chemical sprayer 1 by performing a predetermined operation after turning on the key switch. The controller C executes the control described later based on the signal from the operation panel a6, and switches the positions of the vertical movement switching valve u4 and the on-off valve u1. Further, the controller C is connected to the timer c1 as a timekeeping means and the relay c2 that detects the operation of the key switch and switches the contacts in the circuit.

FIG. 6 is an enlarged view of a front main part of the self-propelled chemical sprayer 1.

As shown in FIG. 6, the accumulator U is arranged at substantially the center of the elevating frame b23 in front of the cabin K, and is located on the substantially center line in the vehicle width direction of the traveling vehicle body 2. As a result, the accumulator U arranged substantially in the center of the traveling vehicle body A serves as a center marker, and the operator can easily operate the self-propelled chemical sprayer 1 in a straight line. In addition, it becomes easy to visually recognize the failure of the accumulator U, and the maintainability is improved.

Further, the on-off valve u1 is housed in a housing X1 arranged in the lower part of the accumulator U shown in FIG. 6, and the vertical movement switching valve u4 is arranged close to the side of the housing X1. It is housed in the housing X2. The accumulator U may be detachably configured on the housing X1. As shown in FIG. 6, the housing X1 and the housing X2 are mounted and fixed close to each other on the elevating frame b23, and the on-off valve u1 and the vertical movement switching valve u4 are arranged close to each other. There is. The housing X1 and the housing X2 may be configured as one housing, and the on-off valve u1 and the vertical movement switching valve u4 may be accommodated in this one housing. As described above, according to the configuration in which the on-off valve u1 and the vertical movement switching valve u4 are integrally directly mounted, the assembling property is good, the assembling man-hours can be reduced, and the arrangement space can be made compact.

The accumulator U, the housing X1 and the housing X2 are configured to be provided at the front portion of the body of the traveling vehicle body 2. Specifically, it is configured to be installed at the front of the aircraft. This facilitates maintenance and management. Further, the spray boom b1 to which the nozzle bn is attached is configured to be able to move up and down to an arbitrary position by raising and lowering the elevating frame b23. The accumulator U, the housing X1 and the housing X2 are attached to the elevating frame b23.

As a result, the accumulator U, the housing X1 and the housing X2 can be moved up and down to any position while maintaining their respective positional relationships, so that the piping is not affected and maintenance management is easy. Will be.

(Open / close control of on-off valve)
FIG. 7 is a flowchart showing a control procedure by the controller C.

The controller C controls the on-off valve u1 and the vertical movement switching valve u4 according to the procedure shown in the flowchart of FIG. As an initial condition, the key switch is turned off, and the on-off valve u1 is switched to the shutoff position u12.

When the controller C acquires the signal that the key switch is turned on (step S101), the controller C controls to switch the on-off valve u1 to the communication position u11 (step S102). As a result, the vibration damping function of the accumulator U is exerted, and the vibration of the spray boom b1 is suppressed. In this way, according to the configuration in which the on-off valve u1 is opened in conjunction with the on operation of the key switch by the operator, the on-off valve u1 is reliably opened and closed when only the power is turned on and the engine is stopped, the engine is running, or during work. The valve u1 is opened. This saves the trouble of the operator manually opening the on-off valve u1 as in the conventional case, so that the convenience is improved. In addition, the operator does not forget to open the on-off valve u1 by manual operation during work. Further, a switch for turning on / off the on-off valve u1 becomes unnecessary.

Next, when the controller C acquires a signal that the boom up switch is turned on or the boom down switch is turned on (step S103), the controller C executes an elevating process of the spray boom b1 described later (step S104).

Further, the controller C controls the on-off valve u1 to be switched to the communication position u11 in step S102, and then switches the on-off valve u1 to the shutoff position u12 when the key switch is turned off (step S105). Control (step S106). As a result, the vibration damping function by the accumulator U is stopped in conjunction with the off operation of the key switch. In this way, according to the configuration in which the spray boom b1 is fixed to the traveling vehicle body A by automatically turning off the vibration damping function by the accumulator U during non-working, for example, self-propelled chemical spraying is performed. It is possible to prevent the spray boom b1 from swinging up and down and coming into contact with an external obstacle during non-working such as when transporting the machine 1. Further, when the accumulator U is removed and maintenance is performed, the on-off valve u1 is switched to the shutoff position u12, so that it is possible to prevent dust and the like from entering the hydraulic circuit.

FIG. 8 is a flowchart showing a procedure by the controller C of the spray boom elevating process (step S104) of FIG. In step S103, the controller C extends the vertical movement switching valve u4 when it acquires a signal that the boom up switch is turned on or the boom down switch is turned on, and when it acquires a signal that the boom up switch is turned on. Switch to position u41 and raise the spray boom b1. When the boom lower switch is turned on, the vertical movement switching valve u4 is switched to the contraction position u42, and the spray boom b1 is lowered (step S201).

At the same time, the on-off valve u1 is immediately switched to the shutoff position u12 (step S202). This makes it possible to improve the responsiveness of the subsequent raising and lowering of the spray boom b1.

Here, the controller C activates the timer c1 at the same time as the start of raising and lowering the spray boom b1, and counts the set time t (step S203). This set time t is set in advance for a predetermined short time, and is, for example, about 1 second.

Next, when the set time t elapses, the controller C switches the on-off valve u1 to the communication position u11 (step S204). That is, the controller C immediately switches the on-off valve u1 to the shutoff position u12 only for a short time immediately after the start of the elevating operation of the spray boom b1, and communicates the on-off valve u1 during the elevating operation of the spray boom b1 after the start of the elevating. Switch to position u11. As a result, quick response can be ensured when the spray boom b1 is raised and lowered, and further, during the raising and lowering operation of the spray boom b1 after the start of the subsequent raising and lowering, the accumulator U exerts a vibration damping function to vibrate the spray boom b1. Can be reduced. As a result, the operation of the spray boom b1 is stable and safety can be improved. That is, according to the configuration in which the on-off valve u1 is opened and controlled after the elevating operation of the spray boom b1 is completed as in the conventional case, the pressure of the hydraulic oil between the elevating cylinder b21 and the accumulator U when the on-off valve u1 is opened. Due to the difference, hydraulic oil may rapidly flow from the elevating cylinder b21 to the accumulator U side, and as a result, the elevating cylinder b21 may be extended or shortened, and the spray boom b1 may be lowered from the stop position to make the operation unstable. However, by controlling the opening / closing valve u1 during the raising / lowering operation of the spraying boom b1, the pressure difference between the hydraulic oil between the raising / lowering cylinder b21 and the accumulator U can be eliminated, and the stable operation of the spraying boom b1 can be realized. .. Here, the set time t is preferably set within 0.5 seconds to 3 seconds, and more preferably set within 0.5 seconds to 1 second.

Subsequently, the controller C controls to switch the vertical movement switching valve u4 to the stop position u43 when the boom up switch or the boom down switch is turned off (step S205). As a result, the raising and lowering of the spray boom b1 is stopped, and the spreading boom b1 raising and lowering process (step S104) in FIG. 7 is completed.

Although not shown in FIGS. 7 and 8, when the boom up switch or the boom down switch is continuously operated for a predetermined time (about 0.5 to 1 second), the spray boom b1 does not move up and down. , The on-off valve u1 is manually closed. In this case, other switches and levers may be provided in place of the boom up switch or boom down switch. As a result, it is possible to easily stop the operation of the accumulator U in a situation where it is not necessary to operate the accumulator U (for example, a situation where there is little unevenness on the road surface) at the discretion of the operator. When the accumulator U is operated again, the boom up switch or the boom down switch is continuously operated for a predetermined time (about 0.5 seconds to 1 second). This eliminates the need for a switch for turning on / off the on-off valve u1.

Further, a vibration sensor may be provided on the machine body, and if the vibration of the machine body is within a predetermined value and continues for a predetermined time or longer, the on-off valve u1 may be automatically closed to stop the operation of the accumulator U. However, when the vibration value of the predetermined value or more continues at least several times, the on-off valve u1 is automatically opened to operate the accumulator.

Further, although the boom up switch and the boom down switch are provided at positions that can be operated while seated in the driver's seat a2 in the cabin K, they are also provided outside the cabin K. As shown in FIG. 2, since the side boom b1L passes by the side of the opening / closing door k3L, it is possible to get on and off under the side boom b1L when getting on and off, but the side boom b1L is raised and lowered when getting on and off. Making it easier to get on and off. Therefore, the side boom b1L can be raised and lowered by operating the boom up switch or boom down switch provided outside the cabin K.

The side booms b1L and b1R are configured to be able to move up and down independently of the elevating frame b23, and are configured to be able to move up and down by an electric hydraulic cylinder ES independent of the hydraulic circuit of FIG. In this case, even if the engine is stopped and the hydraulic pressure is not operating, the side booms b1L and b1R are electrically operated using the power supply of the battery by operating the boom up switch and boom down switch outside the cabin K. It goes up and down by driving the hydraulic cylinder ES of. This makes it easy to get in and out of the cabin K.

FIG. 9 is a time chart showing the operation of the accumulator U of FIG.

In FIG. 9, when the accumulator U is on, the on-off valve u1 is at the communication position u11, and when the accumulator U is off, it is at the shutoff position u12. As shown in FIG. 9, when the key switch is turned on, the accumulator U is normally turned on, but the accumulator U is normally turned on for a set time t immediately after the boom up switch is turned on or the boom down switch is turned on. It is configured to be off. As described above, the set time t is set in advance for a short time (for example, about 1 second), but the responsiveness of raising and lowering the spray boom b1 according to the weight of the spray boom b1 and the needs of the operator can be obtained. In order to realize this, it is possible to adjust within a predetermined range (for example, about 0.5 seconds to 3 seconds) by operating the operation panel a6.

The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

For example, in the above embodiment, as shown in FIG. 4, the elevating frame b23 is rotatably and pivotally supported around the rolling shaft Y by the rolling shaft Y provided at the lower part of the mounting frame b22. However, as shown in FIG. 10, the single-acting roll cylinder b25 is arranged on the left and right one end sides of the elevating frame b23, and the damper b26 is arranged on the left and right other ends, and the single-acting type. The elevating frame b23 may be controlled for rolling by extending or shortening the roll cylinder b25. At this time, by performing the return operation of the single-acting roll cylinder b25 by the dampers b26 arranged on the left and right other ends, the elevating frame sways and vibrates in the rolling direction as compared with the case where an elastic body such as a compression spring is used. Can be suppressed, and stable roll control becomes possible.

FIG. 11 is a circuit diagram showing a part of the hydraulic circuit of the self-propelled chemical sprayer 1 according to another embodiment. In the hydraulic circuit of the self-propelled chemical sprayer 1 according to another embodiment, in addition to the configuration of the hydraulic circuit shown in FIG. 5, a fourth oil passage 105 is connected to the first constant flow valve u2, and a fourth oil passage 105 is further connected. An electromagnetic switching valve that can switch between an extension position u51 as an operation position for extending a single-acting roll cylinder b25, a contraction position u52 as an operation position for contracting, and a stop position u53 for stopping the single-acting roll cylinder b25 in the oil passage 105. The single-acting roll cylinder switching valve u5 is connected. The elevating frame b23 is rotatably and pivotally supported around the rolling shaft Y, and the accumulator U2 controls vibration in the rolling direction of the elevating frame b23.

As shown in FIG. 11, the single-acting roll cylinder switching valve u5 is connected to the fifth oil passage 106, and the fifth oil passage 106 is connected to the piston side chamber b251 of the single-acting roll cylinder b25 and for rolling. It is connected to a second on-off valve u7 capable of switching between a communication position u71 that communicates with the accumulator U2 and a cutoff position u72 that cuts off communication. The controller C controls to switch the on-off valve u7 to the communication position u71 when the key switch is turned on. As a result, the vibration damping function of the accumulator U2 is exerted, and the vibration of the elevating frame b23 in the rolling direction is suppressed. Further, when the accumulator U2 is removed and maintenance is performed, the on-off valve u7 is switched to the shutoff position u72, so that it is possible to prevent dust and the like from entering the hydraulic circuit.

The single-acting roll cylinder switching valve u5 is connected to the second discharge oil passage 107 that returns the hydraulic oil to the hydraulic oil tank T, and is connected to the fourth oil passage 105 and the second discharge oil passage 107. A relief valve u6 is provided. Although not shown, the single-acting roll cylinder switching valve u5 and the second on-off valve u7 are connected to the controller C, and the position can be controlled by the controller C. The single-acting roll cylinder switching valve u5 and the second on-off valve u7 are housed in the housing X3 shown in FIG.

Here, in the plan view of the airframe, the accumulators U and U2 may be arranged on either the left side or the right side of the center line in the traveling direction of the airframe, and the hydraulic valve may be arranged on the other side. .. In this way, by arranging the heavy accumulator and the hydraulic valve separately to the left and right with respect to the center line in the traveling direction of the aircraft, the left-right balance of the aircraft is improved.

Further, the on-off valve to the accumulators U and U2 may be open, and an indicator light indicating the state in which the accumulators U and U2 can be operated may be provided near the key switch or around the handle of the operation unit. This allows the operator to easily check the operating status of the accumulators U and U2 while the vehicle is stopped or running (work, movement). According to such a configuration, it is particularly effective when there is no on / off switch for operating the accumulators U and U2 (a configuration in which the accumulators U and U2 are automatically operated in conjunction with the on / off of the key switch).

A Traveling vehicle body a1 Main frame a2 Driver's seat a3 Steering handle a4 Front wheel a5 Rear wheel a6 Operation panel a7 Bonnet B Chemical spraying device bn Nozzle b1 Spraying boom b2 Supporting device b20 Lifting link b21 Lifting cylinder b22 Mounting frame b23 Lifting frame b24 Opening / closing cylinder b25 Single-acting roll cylinder K Cabin k1 Cabin frame k2 Cabin roof k3L, k3R Open / close door T Hydraulic oil tank U Accumulator U2 Roll accumulator P1 1st pump P2 2nd pump u1 Open / close valve u2 1st constant flow valve u3 2nd fixed Divided flow valve u4 Vertical movement switching valve u5 Single-acting roll cylinder switching valve u6 Relief valve u7 Second on-off valve Y Rolling shaft

Claims (3)

The traveling vehicle body (A) that drives the aircraft and
The operation unit (a6) that accepts the operator's operation,
A chemical spraying unit (b1) configured to be able to move up and down by extending or shortening the lifting cylinder (b21), and
An accumulator (U) connected to the elevating cylinder (b21) and storing a pressurized working fluid, and
An on-off valve (u1) that opens and closes a passage that communicates the elevating cylinder (b21) and the accumulator (U).
A control unit (C) configured to be able to acquire operation information of the operation unit (a6) and to control expansion or contraction of the elevating cylinder (b21) and opening / closing of the on-off valve (u1). It is a self-propelled chemical sprayer equipped with
The operation unit (a6) includes a key switch for turning on the power of the self-propelled drug sprayer.
The control unit (C) opens and controls the on-off valve (u1) on condition that the key switch is operated and the power of the self-propelled drug sprayer is turned on.
A self-propelled drug sprayer, characterized in that the on-off valve (u1) is closed and controlled on condition that the key switch is operated to turn off the power of the self-propelled drug sprayer. When the control unit (C) is operated to extend or shorten the elevating cylinder (b21) in the operation unit (a6),
The on-off valve (u1) is controlled to be closed and then opened for a predetermined set time (t), and the set time (t) is within the range of 0.5 seconds to 1 second. The self-propelled drug sprayer according to claim 1. The self-propelled drug sprayer according to claim 2, wherein the set time (t) can be adjusted by operating the operation unit (a6).

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