Boom sprayer

Abstract

To provide a boom sprayer including a horizontal mechanism mounted to a travel device that can reduce cost, increase a working speed and improve work efficiency by shortening standby time.SOLUTION: A boom sprayer extends a lock cylinder 17 (to maximum extension state) to space apart between a pair of stopper bodies 18, 19 in opposite directions from a lock part 11G, thereby maintaining a horizontal state of a boom 4 with a weight balance, and contracts the lock cylinder 17 (to maximum contraction state) to bring the pair of stopper bodies 18, 19 come close to each other and come close to (hold) the lock part 11G from the opposite directions (facing directions), thereby fixing (locking) a support frame 11 for supporting the boom 4 to a machine body frame 2.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a boom sprayer, and particularly to a boom sprayer mounted on a traveling device such as a tractor.

Background Art

[0002] A boom sprayer is a working machine that is mounted (directly mounted or towed) on a traveling device such as a tractor or a self-propelled body, and sprays a liquid material such as a chemical (spraying material) over a wide range while traveling through a farm field or the like. The boom sprayer includes a boom that is extended to both left and right sides or one of the left and right sides along a horizontal direction intersecting the traveling direction, and sprays the liquid material toward the farm field from a plurality of nozzles arranged at predetermined intervals on the boom, whereby the liquid material can be sprayed over a wide range in one stroke from near the ground.

[0003] Such a boom sprayer is known in the art that includes a horizontal mechanism capable of maintaining the horizontal state of the boom against rolling (oscillation) of the body caused by unevenness of the traveling surface or the like. In a horizontal mechanism of a conventional boom sprayer, a support frame that supports the boom is pivotally supported on the body, and is provided with a mechanism that maintains the horizontal position of the entire boom by the weight balance of the boom deployed horizontally in the left-right direction (see, for example, Patent Document 1 below).

[0004] Furthermore, in the conventional boom sprayers mentioned above, if the weight balance of the left and right booms is disrupted by extending or retracting the boom that is deployed to one side, it becomes impossible to maintain the boom's horizontal position. Therefore, it is necessary to provide a locking mechanism (such as a hydraulic cylinder for locking) that fixes the support frame supporting the boom to the machine before such operations are performed. Also, when moving the machine without performing any work, it becomes difficult to maintain the boom's horizontal position if the travel speed is higher than during work, so in such cases, it is also necessary to fix the support frame supporting the boom to the machine. In addition, if the field surface itself is sloped, it is necessary to tilt the booms that are deployed to the left and right along the field surface (so that they are parallel to the field surface), and to accommodate this, it is necessary to provide a tilting mechanism (such as a hydraulic cylinder for tilting) that holds the support frame supporting the boom to the machine in a tilted position. To address these requirements, boom sprayers equipped with a horizontal mechanism that also include a locking mechanism (such as a hydraulic cylinder for locking) and a tilting mechanism (such as a hydraulic cylinder for tilting) have been proposed (see, for example, Patent Documents 2 and 3 below). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Patent No. 6527028 [Patent Document 2] Patent No. 5870006 [Patent Document 3] Japanese Patent Publication No. 2022-039392 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The boom sprayer disclosed in Patent Document 2 above locks the center boom so that it cannot swing by having movable parts provided in a pair of locking mechanisms (locking hydraulic cylinders) move in opposite directions in the left-right direction and contact the vehicle body or the center boom. As a result, two hydraulic cylinders, which are expensive actuators, are required, increasing production costs. In addition, the amount of oil required to operate two hydraulic cylinders slows down the operation to lock or release the horizontal mechanism, resulting in a longer waiting time until locking or releasing (unlocking) and a problem of reduced work efficiency.

[0007] Furthermore, the boom sprayer disclosed in Patent Document 3 has piston rods (hereinafter sometimes simply referred to as rods) arranged in opposite directions within the cylinder tube of a single locking mechanism (locking hydraulic cylinder). When operated, these piston rods extend and retract simultaneously in opposite directions, and the center boom is locked in an immovable position by extending until the piston heads of the piston rods contact the respective support parts. In other words, it is a structure that combines the two hydraulic cylinders of Patent Document 2 into one. As a result, the internal structure of the hydraulic cylinder becomes complex, and production costs increase. Also, although it is a single hydraulic cylinder, there are two passages for introducing oil, and when operating the hydraulic cylinder, the same amount of oil as operating two hydraulic cylinders is still required. Similar to Patent Document 2, the operation to lock or free (unlock) the horizontal mechanism is slow, the waiting time until locking or freeing (unlocking) is long, and there is a problem of reduced work efficiency.

[0008] This invention was proposed to address these problems and aims to provide a boom sprayer equipped with a horizontal mechanism mounted on a traveling device that can reduce costs and improve work efficiency by increasing operating speed or shortening waiting time. [Means for solving the problem]

[0009] To solve these problems, the boom sprayer according to the present invention has the following configuration. That is, a boom sprayer equipped with a horizontal mechanism that maintains the horizontal state of the boom by the weight balance of the boom deployed horizontally to the left and right, with a support frame that supports the boom pivotally supported on the machine frame attached to the traveling device, the horizontal mechanism comprising a single lock cylinder having a pair of stopper bodies consisting of a base-end stopper body provided on a cylinder tube and a tip-end stopper body provided on a rod, the single lock cylinder being able to move the pair of stopper bodies apart or closer to each other along the machine frame in accordance with the extension and contraction of the lock cylinder, and a lock portion provided between the pair of stopper bodies on the support frame, characterized in that it is possible to switch between a free state in which the boom is maintained in a horizontal state by weight balance by extending the lock cylinder to separate the pair of stopper bodies from each other and move them away from the lock portion in the opposite direction, and a locked state in which the support frame that supports the boom is fixed to the machine frame by contracting the lock cylinder to bring the pair of stopper bodies closer to each other and approach the lock portion from the opposite direction.

[0010] In a preferred embodiment, the machine frame is provided with a movement limiting portion that restricts the movement of each of the pair of stopper bodies in the direction along the machine frame.

[0011] In another preferred embodiment, the movement limiting portion is comprised of an insertion hole through which each of the pair of stopper bodies is inserted so as to be movable in a direction along the machine frame.

[0012] In another preferred embodiment, each of the pair of stopper bodies comprises a sliding portion connected to the cylinder tube or the rod and slidably disposed on the machine frame, and a stopper portion connected to the sliding portion and positioned opposite the locking portion so as to be spaced apart or approaching.

[0013] In another preferred embodiment, the lock cylinder is supported by the pair of stopper bodies without being fixed to the machine frame.

[0014] In another preferred embodiment, the locking portion is formed in a circular cross-section.

[0015] In another preferred embodiment, the support frame supporting the boom is provided with an inclined cylinder for holding it in an inclined state relative to the machine frame, wherein the inclined cylinder can extend and retract in the free state to hold the support frame supporting the boom in an inclined state relative to the machine frame.

[0016] In another preferred embodiment, the support frame has a boom support portion that supports the boom and a connecting portion that is rotatably mounted relative to the boom support portion, the inclined cylinder is disposed between the boom support portion and the connecting portion, and a damper made of an elastic member is disposed between the connecting portion and the machine frame.

[0017] In another preferred embodiment, the locking portion is provided on the connecting portion. [Effects of the Invention]

[0018] Boom sprayers with these features require only one lock cylinder (such as a hydraulic cylinder for locking) as an actuator, thus reducing production costs. Furthermore, only one cylinder's worth of working fluid is needed for the lock cylinder, resulting in faster locking or unlocking of the horizontal mechanism, shorter waiting times, and improved work efficiency. This allows for cost reduction and improved work efficiency through increased operating speed or reduced waiting times in boom sprayers equipped with a horizontal mechanism mounted on a travel device. [Brief explanation of the drawing]

[0019] [Figure 1A] This is a perspective view taken from the rear at an oblique angle, showing an example of the overall configuration of a boom sprayer according to an embodiment of the present invention. [Figure 1B] This is a rear view showing an example of the overall configuration of a boom sprayer according to an embodiment of the present invention. [Figure 1C] It is a side view showing an example of the overall configuration of a boom sprayer according to an embodiment of the present invention. [Figure 2A] It is an oblique rear perspective view showing an example of the configuration of a leveling mechanism of a boom sprayer according to an embodiment of the present invention. [Figure 2B] It is a rear view showing an example of the configuration of a leveling mechanism of a boom sprayer according to an embodiment of the present invention. [Figure 2C] It is a side view showing an example of the configuration of a leveling mechanism of a boom sprayer according to an embodiment of the present invention. [Figure 3A] It is an oblique rear perspective view showing the free state of main parts of a leveling mechanism of a boom sprayer according to an embodiment of the present invention. [Figure 3B] It is a rear view showing the free state of main parts of a leveling mechanism of a boom sprayer according to an embodiment of the present invention. [Figure 4A] It is an oblique rear perspective view showing the locked state of main parts of a leveling mechanism of a boom sprayer according to an embodiment of the present invention. [Figure 4B] It is a rear view showing the locked state of main parts of a leveling mechanism of a boom sprayer according to an embodiment of the present invention. [Figure 5] It is an explanatory diagram showing switching between the free state and the locked state of the leveling mechanism when the traveling device is tilted to the left. [Figure 6] It is an explanatory diagram showing the right-tilted state of the leveling mechanism when the traveling device is tilted to the left. [Figure 7] It is an explanatory diagram showing switching between the free state and the locked state of the leveling mechanism when the traveling device is tilted to the right. [Figure 8] It is an explanatory diagram showing the left-tilted state of the leveling mechanism when the traveling device is tilted to the right. Mode for Carrying Out the Invention

[0020] Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same reference numerals in different figures indicate parts with the same function, and redundant explanations in each figure will be omitted as appropriate. In addition, terms indicating directions such as up and down, left and right, front and back are based on the normal direction of travel of the running gear.

[0021] First, an example of the overall configuration of a boom sprayer according to an embodiment of the present invention will be explained using Figures 1A to C. The boom sprayer 1 is directly mounted on a tractor (not shown in Figures 1A to C; see Patent Document 1, etc.), which is a traveling device, and sprays chemicals and the like while traveling on a field. It comprises a machine frame 2 directly mounted on the tractor, a tank 3 mounted on the machine frame 2, and a boom 4 supported by the machine frame 2 via a horizontal mechanism 10. The boom 4 extends along a horizontal direction intersecting the direction of travel of the tractor, either on both the left and right sides or on one side of the left and right sides. Multiple nozzles 5 are arranged on the boom 4 to spray chemicals and the like stored in the tank 3 towards the field.

[0022] The chemicals stored in tank 3 are supplied by the pump's driving pressure to the spray pipe 6 supported by the boom 4 mentioned above, and are sprayed from multiple nozzles 5 arranged at predetermined intervals along this spray pipe 6.

[0023] The horizontal mechanism 10 will now be described. As shown in Figures 1A to C and 2A to C, the horizontal mechanism 10 pivotally supports a support frame 11 that supports the boom 4 with respect to the machine frame 2, and maintains the horizontal position of the boom 4 by balancing the weight of the boom 4 which is extended horizontally to the left and right.

[0024] The support frame 11 has a generally symmetrical shape and includes boom support sections 11A extending to the left and right. In the illustrated example, the boom support section 11A has a horizontally elongated trapezoidal frame shape when viewed from the rear, and the boom 4 is provided at both the left and right ends so as to be deployable or retractable (see Figures 1A and 1B). The support frame 11 also includes a connecting section 11B extending vertically on the traveling device side (front side) of the boom support section 11A. The central upper part of the boom support section 11A and the upper part of the connecting section 11B are both rotatably supported by the machine frame 2 by a rotation axis 12. The boom support section 11A and the connecting section 11B are capable of relative rotation around the rotation axis 12 within the support frame 11. In the illustrated example, the machine frame 2 includes a lifting rail 2A and a lifting frame 2B that is supported on the lifting rail 2A so as to be able to move up and down. The support frame 11 (boom support portion 11A and connecting portion 11B) is pivotally supported on the lifting frame 2B by a rotating shaft 12. The illustrated machine frame 2 also includes a lifting cylinder 2C that moves the lifting frame 2B up and down along the lifting rail 2A.

[0025] A damper 13, which incorporates a balance (vibration-damping) spring made of an elastic material, is connected between the support frame 11 and the lifting frame 2B. One end of the damper 13 is connected to a damper support part 11D located in the upper and lower center of the connecting part 11B of the support frame 11, and the other end is connected to a damper support part 2D located on the lifting frame 2B of the machine frame 2. The damper support part 11D of the connecting part 11B of the support frame 11 and the damper support part 2D of the lifting frame 2B of the machine frame 2 are located side by side, and the damper 13 is positioned between the connecting part 11B of the support frame 11 and the lifting frame 2B of the machine frame 2 so as to extend from left to right. Therefore, when the support frame 11 is in a free state as described later, the support frame 11 is held in a horizontal position by the balance of the tension of the balance spring built into the damper 13.

[0026] Furthermore, the horizontal mechanism 10 includes a (single) inclined cylinder (such as an inclined hydraulic cylinder) 15 positioned between the boom support portion 11A and the connecting portion 11B of the support frame 11, which causes the boom support portion 11A of the support frame 11 to swing around the rotation axis 12. One end of the inclined cylinder 15 (the base of the cylinder tube) is pivotally supported by a cylinder support portion 11E provided on the boom support portion 11A of the support frame 11, and the other end (the tip of the rod) is pivotally supported by a cylinder support portion 11F provided at the lower part of the connecting portion 11B of the support frame 11 (below the damper support portion 11D). As a result, when the inclined cylinder 15 extends or retracts while the support frame 11 is in a free state as described later, the boom support portion 11A of the support frame 11 swings around the rotation axis 12, and the boom 4 supported by the boom support portion 11A of the support frame 11 is held in an arbitrary inclined state relative to the machine frame 2.

[0027] Furthermore, the horizontal mechanism 10 includes a (single) lock cylinder (such as a hydraulic locking cylinder) 17 positioned between the aircraft frame 2 and the support frame 11, which swings like a pendulum around the rotation axis 12, and fixes the support frame 11 to the aircraft frame 2 (see Figures 2B and 2C).

[0028] As can be clearly seen by referring to Figures 3A, B and 4A, B, the lock cylinder 17 is provided with a base-side stopper body 18 (hereinafter referred to as stopper body 18) at one end (the cylinder tube root side) and a tip-side stopper body 19 (hereinafter referred to as stopper body 19) at the other end (the rod tip side). These two stopper bodies 18 and 19 constitute a left and right pair of stopper bodies 18 and 19 that are arranged opposite each other along the lifting frame 2B of the machine frame 2, and each of these left and right pair of stopper bodies 18 and 19 is slidably disposed on the lifting frame 2B of the machine frame 2. In the illustrated example, each of these pair of stopper bodies 18 and 19 is slidably externally attached to or engaged with the lifting frame 2B of the machine frame 2. As a result, the lock cylinder 17 is supported by this pair of stopper bodies 18 and 19 without being fixed to the lifting frame 2B of the machine frame 2. In the illustrated example, the lock cylinder 17 is positioned below the lifting frame 2B of the aircraft frame 2 and extends left and right along the lifting frame 2B of the aircraft frame 2.

[0029] In the illustrated example, each stopper body 18, 19 provided at both ends of the lock cylinder 17 comprises a sliding portion 18A, 19A consisting of a bracket formed in a substantially rectangular cross-section, which is connected to the cylinder tube or rod of the lock cylinder 17 and slidably disposed (exteriorated or engaged, etc.) on the machine frame 2, and a stopper portion 18C, 19C consisting of a stopper bolt, which is connected to mounting portions 18B, 19B protruding from the rear surface of the sliding portions 18A, 19A and is positioned opposite to the lock portion 11G described later, so as to be able to move away from or closer to it. The pair of stopper bodies 18, 19 provided at both ends of the lock cylinder 17 described above can move away from or closer to each other along the lifting frame 2B of the machine frame 2 in accordance with the extension and contraction of the lock cylinder 17, between the fully extended and fully retracted states of the lock cylinder 17. Here, the approach and separation of the stopper bodies relative to the lock cylinder 17 is performed by the extension and contraction of a rod provided only on one end of the lock cylinder 17. Specifically, the stopper body on the tip side (side 19 in this embodiment) is connected to the tip of the lock cylinder 17 via a rod that extends and retracts due to the lock cylinder 17, while the stopper body on the base side (side 18 in this embodiment) is directly connected to the lock cylinder 17. The lock cylinder 17 only needs to introduce the amount of oil necessary to move the rod on the tip side, and has the advantage of faster operating speed compared to a method that has movable parts on both the left and right sides.

[0030] Furthermore, in the illustrated example, the lifting frame 2B of the aircraft frame 2 is provided with through holes 2S and 2T, which are elongated holes extending to the left and right, through which each stopper body 18 and 19 is inserted so as to be movable in a direction along the lifting frame 2B of the aircraft frame 2. By inserting each stopper body 18 and 19 into each through hole 2S and 2T, the movement (amount) of each stopper body 18 and 19 in the direction along the lifting frame 2B of the aircraft frame 2 is restricted between the fully extended and fully retracted states of the lock cylinder 17. In other words, the through holes 2S and 2T provided in the lifting frame 2B of the aircraft frame 2 act as movement restrictors that limit (define) the movement (amount) of each stopper body 18 and 19 in the direction along the lifting frame 2B of the aircraft frame 2 between the fully extended and fully retracted states of the lock cylinder 17.

[0031] Furthermore, the horizontal mechanism 10 includes a (single) locking part 11G between the aforementioned pair of stopper bodies 18 and 19 in the support frame 11, together with the lock cylinder 17, to fix the support frame 11 to the machine frame 2. In the illustrated example, the locking part 11G is provided at the lower part of the connecting part 11B of the support frame 11 and consists of a pin member formed with a circular cross-section when viewed in the front-rear direction.

[0032] In the horizontal mechanism 10 with this configuration, by extending the lock cylinder 17 to its maximum position in response to user operation, the pair of left and right stopper bodies 18 and 19 provided at both ends of the lock cylinder 17 are separated from each other, and the stopper parts 18C and 19C are moved away from the lock part 11G in the opposite direction, thereby maintaining the boom 4 supported by the support frame 11 in a horizontal position by weight balance (Figures 3A, 3B, 5, and 7). This state is called the free state (or unlocked state). In this free state (or unlocked state), the support frame 11 that supports the boom 4 extending to the left and right is supported to rotate freely around the rotation axis 12 according to the weight balance. As a result, when the weight balance of the boom 4 extended to the left and right is equal, the boom 4 will maintain a horizontal position against the rolling (oscillation) of the machine frame 2.

[0033] On the other hand, by retracting the lock cylinder 17 to its most retracted state in response to user operations, the pair of stopper bodies 18 and 19 provided at both ends of the lock cylinder 17 are brought closer together, and the stopper portions 18C and 19C are brought closer to (clamped) the lock portion 11G from the opposite direction (opposing direction), thereby fixing the boom 4 supported by the support frame 11 to the machine frame 2 (Figures 4A, 4B, 5, and 7). This state is referred to as the fixed state (or locked state). In this fixed state (or locked state), the support frame 11 that supports the boom 4 extending to the left and right is held down from the opposite direction (opposing direction) by the stopper portions 18C and 19C of the stopper bodies 18 and 19, and becomes fixed to the machine frame 2.

[0034] Here, even when the support frame 11 supporting the boom 4 is tilted relative to the machine frame 2, and the lock cylinder 17 is retracted so that the stopper parts 18C and 19C come into contact with the lock part 11G, the lock part 11G is made of a pin member formed with a circular cross-section when viewed in the front-rear direction, which allows the lock part 11G and the stopper parts 18C and 19C to come into smooth contact and fix the boom 4 to the machine frame 2.

[0035] Furthermore, in the free state of the horizontal mechanism 10 when the traveling device is tilted to the left as shown in Figure 5, as shown in Figure 6, by extending the tilt cylinder 15, the boom support portion 11A and the connecting portion 11B on the support frame 11 rotate in relatively opposite directions (to separate from each other), and the boom 4 supported by the boom support portion 11A of the support frame 11 can be held in a further rightward tilt relative to the machine frame 2. Although not shown in the illustration, in this free state, by retracting the tilt cylinder 15, it is also possible to hold the boom 4 supported by the boom support portion 11A of the support frame 11 in a further leftward tilt relative to the machine frame 2 (approaching the tilt of the boom in the fixed state).

[0036] Furthermore, in the free state of the horizontal mechanism 10 when the traveling device is tilted to the right as shown in Figure 7, by contracting the tilt cylinder 15 as shown in Figure 8, the boom support portion 11A and the connecting portion 11B on the support frame 11 rotate in opposite directions (to separate from each other), and the boom 4 supported by the boom support portion 11A of the support frame 11 can be held in a further leftward tilt relative to the machine frame 2. Although not shown in the illustration, in this free state, by extending the tilt cylinder 15, it is also possible to hold the boom 4 supported by the boom support portion 11A of the support frame 11 in a further rightward tilt relative to the machine frame 2 (approaching the tilt of the boom in the fixed state).

[0037] As described above, the horizontal mechanism 10 of the boom sprayer 1 according to this embodiment uses one lock cylinder (such as a hydraulic cylinder for locking) 17 which acts as an actuator. Sliding parts 18A and 19A are provided at the tip of the rod and the base of the cylinder tube of the lock cylinder 17, and stopper parts 18C and 19C are provided on the sliding parts 18A and 19A to form stopper bodies 18 and 19. In addition, a lock part 11G is provided on the support frame 11 that supports the boom 4, adjacent to the stopper parts 18C and 19C. By extending the lock cylinder 17 to its fully extended state, the stopper bodies 18 and 19 (a pair of left and right) provided at both ends of the lock cylinder 17 are separated from each other, and the stopper parts 18C and 19C are moved away from the lock part 11G in the opposite direction, so that the boom 4 supported by the support frame 11 can move freely in the roll direction (free state). By retracting the lock cylinder 17 to its most retracted state, the stopper bodies 18 and 19 (a pair of left and right) provided at both ends of the lock cylinder 17 are brought closer to each other, and the stopper parts 18C and 19C are brought closer to the lock part 11G from the opposite direction (opposing direction) (clamping), thereby fixing the boom 4 supported by the support frame 11 to the machine frame 2 (locked state).

[0038] As described above, the horizontal mechanism 10 of the boom sprayer 1 according to this embodiment is a single lock cylinder 17 having a pair of (left and right) stopper bodies 18 and 19, which consist of a base-side stopper body 18 provided on the cylinder tube and a tip-side stopper body 19 provided on the rod, wherein the pair of stopper bodies 18 and 19 can move apart from or approach each other along the machine frame 2 in accordance with the extension and contraction of the lock cylinder 17 (between the fully extended and fully retracted states of the lock cylinder 17), and a locking portion 1 provided between the pair of stopper bodies 18 and 19 in the support frame 11 The device is equipped with a lock cylinder 17, and by extending the lock cylinder 17 (to its fully extended state), the pair of stopper bodies 18 and 19 are separated from each other and moved away from the locking part 11G in the opposite direction, thereby maintaining the boom 4 in a horizontal position by weight balance. The device is also equipped with a lock cylinder 17, and the device is switchable between a free state and a locked state in which the support frame 11 that supports the boom 4 is fixed (locked) to the machine frame 2 by retracting the lock cylinder 17 (to its fully retracted state), bringing the pair of stopper bodies 18 and 19 closer to each other and approaching (clamping) the locking part 11G from the opposite direction (opposing direction).

[0039] In other words, the horizontal mechanism 10 of the boom sprayer 1 according to this embodiment includes a locking mechanism that fixes the support frame 11 supporting the boom 4 to the machine frame 2, and the locking mechanism is a single lock cylinder 17 having a pair of (left and right) stopper bodies 18, 19 consisting of a base-end stopper body 18 provided on the cylinder tube and a tip-end stopper body 19 provided on the rod, and the pair of stopper bodies 18, 19 can move apart from or approach each other along the machine frame 2 in accordance with the extension and contraction of the lock cylinder 17 (between the fully extended and fully retracted states of the lock cylinder 17) The device comprises a 7 and a locking portion 11G provided between the pair of stopper bodies 18 and 19 in the support frame 11. By retracting the lock cylinder 17 (to its most retracted state), the pair of stopper bodies 18 and 19 are brought closer to each other and approached (clamped) the locking portion 11G from the opposite direction (opposing direction), thereby fixing (locking) the support frame 11 that supports the boom 4 to the machine frame 2. By extending the lock cylinder 17 (to its most extended state), the pair of stopper bodies 18 and 19 are separated from each other and moved away from the locking portion 11G in the opposite direction, thereby releasing the fixed (locked) state.

[0040] The boom sprayer 1 of this embodiment, possessing these features, requires only one lock cylinder (such as a hydraulic cylinder for locking) 17 as an actuator, thereby reducing production costs. Furthermore, the amount of working fluid supplied to the lock cylinder 17 is limited to that of a single lock cylinder, resulting in faster operation for locking or releasing the horizontal mechanism 10, shorter waiting times for locking or releasing, and improved work efficiency. As a result, the boom sprayer 1 equipped with a horizontal mechanism 10 mounted on a traveling device can achieve cost reduction and improved work efficiency through increased operating speed or reduced waiting times.

[0041] Furthermore, the inclined cylinder 15 and the locking cylinder 17 may be any cylinder device (fluid cylinder) that uses hydraulic or pneumatic pressure. Also, the number and placement of the dampers 13 and inclined cylinders 15 are not limited to the embodiments described above.

[0042] Although embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and any design changes, etc., that do not depart from the spirit of the present invention are also included. [Explanation of symbols]

[0043] 1: Boom sprayer, 2: Machine frame, 2A: Lifting rail, 2B: Lifting frame, 2C: Lifting cylinder, 2D: Damper support, 2S, 2T: Through hole (movement restriction part), 3: Tank, 4: Boom, 5: Nozzle, 6: Spray pipe, 10: Horizontal mechanism, 11: Support frame, 11A: Boom support, 11B: Connecting part, 11D: Damper support, 11E, 11F: Cylinder support, 11G: Locking part, 12: Rotating shaft, 13: Damper, 15: Inclined cylinder, 17: Locking cylinder, 18, 19: Stopper body (base end stopper body, tip end stopper body), 18A, 19A: Sliding part, 18B, 19B: Mounting part, 18C, 19C: Stopper part

Claims

1. A boom sprayer equipped with a horizontal mechanism that maintains the boom in a horizontal position by balancing the weight of the boom, which is extended horizontally to the left and right, by pivotally supporting a support frame that supports the boom with respect to the machine frame attached to the traveling device, The aforementioned horizontal mechanism is A single lock cylinder having a pair of stopper bodies consisting of a base-end stopper body provided on a cylinder tube and a tip-end stopper body provided on a rod, wherein the pair of stopper bodies can move apart from or toward each other along the machine frame in accordance with the extension and contraction of the lock cylinder, The support frame comprises a locking portion provided between the pair of stopper bodies, A boom sprayer characterized in that it is possible to switch between a free state, in which the boom is maintained in a horizontal position by weight balance, by extending the lock cylinder to separate the pair of stopper bodies from each other and move them away from the locking part in the opposite direction, and a locked state, in which the support frame that supports the boom is fixed to the machine frame, by retracting the lock cylinder to bring the pair of stopper bodies closer to each other and approach the locking part from the opposite direction.

2. The boom sprayer according to claim 1, characterized in that the machine frame is provided with a movement limiting portion that restricts the movement of each of the pair of stopper bodies in the direction along the machine frame.

3. The boom sprayer according to claim 2, characterized in that the movement limiting portion is composed of an insertion hole through which each of the pair of stopper bodies is inserted so as to be movable in a direction along the machine frame.

4. The boom sprayer according to claim 1, characterized in that each of the pair of stopper bodies comprises a sliding portion connected to the cylinder tube or the rod and slidably disposed on the machine frame, and a stopper portion connected to the sliding portion and positioned opposite the locking portion so as to be spaced apart or approaching.

5. The boom sprayer according to claim 1, characterized in that the lock cylinder is supported by the pair of stopper bodies without being fixed to the machine frame.

6. The boom sprayer according to claim 1, characterized in that the locking portion is formed in a circular cross-section.

7. The support frame that supports the boom is equipped with an inclined cylinder for holding it in an inclined state relative to the machine frame, The boom sprayer according to claim 1, characterized in that the inclined cylinder extends and retracts in the free state, thereby enabling the support frame that supports the boom to be held in an inclined state relative to the machine frame.

8. The support frame has a boom support portion that supports the boom, and a connecting portion that is rotatably mounted relative to the boom support portion. The boom sprayer according to claim 7, characterized in that the inclined cylinder is disposed between the boom support portion and the connecting portion, and a damper made of an elastic member is disposed between the connecting portion and the machine frame.

9. The boom sprayer according to claim 8, characterized in that the locking portion is provided at the connecting portion.

10. A boom sprayer equipped with a horizontal mechanism that maintains the horizontal position of the boom by balancing the weight of the boom, which is extended horizontally to the left and right by pivotally supporting a support frame that supports the boom with respect to the machine frame mounted on the traveling device, and also includes a locking mechanism that fixes the support frame that supports the boom to the machine frame, The locking mechanism is A single lock cylinder having a pair of stopper bodies consisting of a base-end stopper body provided on a cylinder tube and a tip-end stopper body provided on a rod, wherein the pair of stopper bodies can move apart from or toward each other along the machine frame in accordance with the extension and contraction of the lock cylinder, The support frame comprises a locking portion provided between the pair of stopper bodies, A boom sprayer characterized in that the support frame supporting the boom is fixed to the machine frame by contracting the lock cylinder to bring the pair of stopper bodies closer together and approach the lock portion from opposite directions, and the fixed state is released by extending the lock cylinder to separate the pair of stopper bodies from each other and move them away from the lock portion in the opposite direction.

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