Boom sprayer

Abstract

To provide a boom sprayer that minimizes the area where chemical solution cannot be sprayed while suppressing damage caused by contact with the ground, etc. [Solution] A boom sprayer 1 is provided with a side boom 3 that can be folded when stored, the side boom 3 having a base boom 31 and a front boom 33 located at the very front of the side boom 3 and pivotally supported by a storage folding shaft 32 provided at the tip of the base boom 31, and a retraction pivot shaft 6 is provided at the base of the front boom 33, on the tip side of the storage folding shaft 32, which rotates and retracts the front boom 33 in the direction of the force when a force is applied to the front boom 33 in the front-rear direction.

Description

Technical Field

[0001] The present invention relates to a boom sprayer capable of spraying a chemical solution or the like.

Background Art

[0002] A boom sprayer is for spraying a chemical solution or the like in a field, and is configured as an attachment mounted on a traveling vehicle such as a tractor or a towing vehicle, or as a dedicated spraying vehicle integrated with the traveling vehicle.

[0003] Conventional boom sprayers are composed of a center boom and side booms extending left and right from this center boom.

[0004] The longer the side boom is, the more merit there is in that a chemical solution can be sprayed over a wider area. On the other hand, when the side boom is lengthened, there are demerits such as a decrease in maneuverability during movement without chemical solution spraying and a need for a large storage space.

[0005] In response to such demerits, boom sprayers that can fold the side booms during movement or storage have been proposed heretofore. For example, Japanese Unexamined Patent Application Publication No. 2021 - 69303 proposes a boom sprayer in which left and right side booms can be folded backward with respect to a center boom fixed in front of a traveling vehicle (Patent Document 1). Also, the applicant of the present application has developed and disclosed an invention related to a boom sprayer in Japanese Unexamined Patent Application Publication No. 2013 - 116078 that can fold the left and right side booms in a two - fold manner and further fold the side booms with respect to the center boom (Patent Document 2).

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

[0007] Incidentally, during spraying operations, the side boom may come into contact with the ground due to the tilting of the vehicle or other moving objects from side to side. In particular, if the side boom is long, even a slight tilt will increase the vertical range of the tip, making it more likely to come into contact with the ground. If the vehicle continues to move while in contact with the ground, the tip will be pushed in the opposite direction of travel, which may damage the side boom.

[0008] To avoid damage to the side boom, one could consider rotating and retracting the side boom in the direction of the applied force. However, as shown in Figure 10, rotating and retracting the side boom creates areas that are not sprayed, resulting in unstable spray width and amount, and causing uneven spraying. Furthermore, since boom sprayers spray while moving, if the side boom remains rotated and retracted, the areas that are not sprayed will expand as the machine moves forward.

[0009] This invention was made to solve the above-mentioned problems, and aims to provide a boom sprayer that can minimize the area where chemical solution cannot be sprayed while suppressing damage caused by contact with the ground, etc. [Means for solving the problem]

[0010] The boom sprayer according to the present invention solves the problem of preventing damage by rotating and retracting the leading boom in the opposite direction to the direction of travel when it collides with the ground or the like, and is equipped with a side boom that can be folded when stored, the side boom having a base boom and a leading boom located at the very front of the side boom and supported by a folding shaft for storage provided at the tip of the base boom, and a retraction pivot shaft is provided at the base of the leading boom at a position on the tip side of the folding shaft for storage that rotates and retracts the leading boom in the direction of the force when a force is applied to the leading boom in the front-rear direction.

[0011] Furthermore, in one aspect of the present invention, in order to solve the problem of minimizing the area in which the chemical solution cannot be sprayed by rotational retraction, the axial direction of the retraction rotation shaft may be inclined from vertical toward the tip of the leading boom.

[0012] Furthermore, in one aspect of the present invention, in order to solve the problem of preventing the leading boom from unintentionally rotating and retracting due to light contact with crops or the like, changes in the speed of a moving vehicle, or vibrations caused by uneven road surfaces, the retraction pivot shaft may be equipped with a clutch mechanism that rotates and retracts the leading boom in the direction of the force when a force of a predetermined strength or more is applied to the leading boom in the front-rear direction.

[0013] Furthermore, in one aspect of the present invention, in order to solve the problem of constructing a clutch mechanism with a simple structure, the leading boom is pivotally supported so as to be axially slidable along the retractable pivot shaft, and the clutch mechanism may have an elastic member that presses the leading boom either above or below the retractable pivot shaft, a recessed groove formed on either the leading boom or the retractable pivot shaft, and a protruding portion formed on the other side where the recessed groove is not formed, which fits into the recessed groove and escapes from the recessed groove against the elastic force of the elastic member when the leading boom rotates to a predetermined angle.

[0014] Furthermore, in one aspect of the present invention, in order to solve the problem of suppressing the expansion of the area that cannot be sprayed in the direction of travel, an automatic return slope may be formed on either the leading edge boom in which the fitting groove is formed or the retractable pivot shaft, which is formed in a downward sloping manner toward the fitting groove and guides the fitting protrusion.

[0015] Furthermore, in one aspect of the present invention, in order to solve the problem of reliably returning the leading boom automatically, the automatic return slope may have a gradient along a spiral trajectory that results in a constant axial movement proportional to the amount of rotation of the leading boom. [Effects of the Invention]

[0016] According to the present invention, damage caused by contact with the ground or other surfaces can be suppressed while minimizing the area where the chemical solution cannot be sprayed. [Brief explanation of the drawing]

[0017] [Figure 1] This is a rear perspective view showing one embodiment of a towing vehicle equipped with a boom sprayer according to the present invention. [Figure 2] This is a front view showing the vicinity of the retractable pivot shaft in this embodiment. [Figure 3] This is a plan view of Figure 2. [Figure 4] This embodiment is an enlarged front view showing the vicinity of the retractable pivot shaft in a state where the fitting protrusion is fitted into the fitting recess. [Figure 5] This embodiment is an enlarged front view showing the vicinity of the retractable pivot shaft in a state where the embedded protrusion has disengaged from the embedded recess. [Figure 6] This is a perspective view showing another embodiment in which the automatic return slope is made steeper. [Figure 7] This is a perspective view showing another embodiment in which automatic return slopes are provided on both the left and right sides of the insertion groove. [Figure 8]In the present embodiment, in the vicinity of the retraction rotating shaft, there are shown front views of (a) a state where the tip boom is deployed, (b) a state where the fitting convex portion has escaped from the fitting concave portion upon receiving a force of a predetermined strength or more, (c) a state where the tip boom is rotationally retracted and the fitting convex portion is guided along the automatic return slope, and (d) a state where the fitting convex portion is locked to the rotation stopper and the tip boom is rotationally retracted to the maximum extent. [Figure 9] The side boom in the present embodiment is a schematic view of (a) a state where the tip boom has collided with the ground, (b) a case where it is rotationally retracted about the folding shaft for storage, and (c) a case where it is rotationally retracted about the inclined retraction rotating shaft. [Figure 10] It is a plan view showing a non-sprayable range when the tip boom is rotationally retracted backward.

Mode for Carrying Out the Invention

[0018] Hereinafter, an embodiment of a boom sprayer according to the present invention will be described with reference to the drawings.

[0019] The boom sprayer 1 of the present embodiment is a boom provided with a mechanism for spraying a chemical liquid or the like. As shown in FIG. 1, it has a center boom 2 and side booms 3 extending left and right from the center boom 2. Hereinafter, each component will be described in detail.

[0020] The center boom 2 connects the side booms 3 to both left and right ends as shown in FIG. 1, and in the present embodiment, it is installed behind the towing vehicle T.

[0021] Note that the boom sprayer 1 is not limited to being installed on the towing vehicle T, and may be configured as an attachment for a vehicle capable of traveling in a field such as a tractor, or as a part of a dedicated spraying vehicle integrated with the traveling vehicle.

[0022] The side boom 3 is a boom that can be deployed when spraying chemicals and folded when moving or storing without spraying chemicals, and is foldably connected to both the left and right ends of the center boom 2. In this embodiment, the side boom 3 has a base boom 31, a storage folding shaft 32 provided at the tip of the base boom 31, and a front boom 33 pivotally supported by the storage folding shaft 32.

[0023] The base boom 31 is a boom connected to the center boom 2, and in this embodiment, it has a first base boom 31a on the center boom 2 side and a second base boom 31b provided at its tip, and is configured to be foldable.

[0024] The first base boom 31a is foldably connected to the left and right ends of the center boom 2, and in this embodiment, it is rotatably connected to the center boom 2 in a substantially horizontal direction or diagonally upward from the horizontal.

[0025] The second base boom 31b is foldably connected to the tip of the first base boom 31a, and in this embodiment, it is configured to rotate and fold in a substantially vertical direction by a horizontal axis perpendicular to the longitudinal direction of the boom.

[0026] Furthermore, the base boom 31 is not limited to being foldable, but may also consist of a single boom that cannot be folded.

[0027] The storage folding shaft 32 is for pivotally supporting the furthest tip boom 33 at the tip of the base boom 31. In this embodiment, as shown in Figures 2 to 3, it is composed of a vertical shaft whose axial direction is oriented substantially vertically at the tip of the second base boom 31b, and pivotally supports the furthest tip boom 33 so that it can be folded in the front-rear direction.

[0028] Furthermore, a telescopic cylinder 4 and a link mechanism 5 are provided on the front outer side of the storage folding shaft 32, connecting the tip of the base boom 31 and the base end 34 of the furthest boom 33.

[0029] The telescopic cylinder 4 is extendable and retractable, and by swinging the link mechanism 5, the leading boom 33 can be rotated in the front-to-back direction with the storage folding shaft 32 as the pivot point, allowing it to be deployed or folded for storage.

[0030] Furthermore, the folding shaft 32 for storage is not limited to a vertical axis; it may also be configured as a horizontal axis with its axial direction oriented approximately horizontally, allowing the leading boom 33 to rotate approximately vertically and be folded.

[0031] The leading edge boom 33 is located at the very tip of the side boom 3 and is pivotally supported by a retractable folding shaft 32. In this embodiment, as shown in Figures 4 and 5, a retractable pivot shaft 6 equipped with a clutch mechanism 7 is provided. In this embodiment, the leading edge boom 33 on the tip side of the retractable pivot shaft 6 is pivotally supported so as to be rotatable with respect to the retractable pivot shaft 6 and slidable in the axial direction along the retractable pivot shaft 6.

[0032] The retraction pivot shaft 6 is an axis for rotating and retracting the leading edge boom 33 in the direction of the force applied to it when a force is applied to the leading edge boom 33. In this embodiment, it is provided at the base end 34 on the tip side of the storage folding shaft 32. In this way, by providing the retraction pivot shaft 6 separately from the storage folding shaft 32, the leading edge boom 33 can be rotated and retracted in the front-rear direction even if the storage folding shaft 32 is not configured as a vertical axis. Furthermore, as shown in Figures 2 and 3, the retraction pivot shaft 6 in this embodiment is located near the storage folding shaft 32, and is formed so that the longitudinal length of the leading edge boom 33 on the tip side of the retraction pivot shaft 6 is longer.

[0033] Furthermore, the retraction pivot shaft 6 is positioned so that its axial direction is inclined toward the tip of the leading boom 33 from the vertical when the leading boom 33 rotates. In this embodiment, the retraction pivot shaft 6 is inclined to tilt approximately 30 degrees toward the tip with respect to the vertical.

[0034] The angle at which the retraction pivot shaft 6 is tilted is not particularly limited, but a larger angle results in a larger amount of retraction relative to the amount of rotation. However, the force required to rotate against gravity also increases, so it is preferable to select an appropriate angle considering the balance between the amount of retraction and the force required for rotation.

[0035] The clutch mechanism 7 is a mechanism for determining a threshold force for rotating and retracting the leading boom 33, and is configured to rotate and retract the leading boom 33 in the direction of the force when a force of a predetermined strength or greater is applied to the leading boom 33 in the front-rear direction. As shown in Figures 4 and 5, the clutch mechanism 7 in this embodiment includes an elastic member 71 for holding the leading boom 33, a recessed groove 72 formed in either the leading boom 33 or the retraction pivot shaft 6, a recessed projection 73 that fits into the recessed groove 72, and an automatic return slope 74 formed in a downward sloping manner toward the recessed groove 72.

[0036] The elastic member 71 is for pressing the tipmost boom 33, which is pivotally supported on the retractable pivot shaft 6, upward or downward along the retractable pivot shaft 6. In this embodiment, as shown in Figure 4, it is composed of a coil spring formed spirally along the outer circumference of the retractable pivot shaft 6.

[0037] Furthermore, a pressing force adjustment plate 75 is detachably fixed to the upper part of the elastic member 71 with respect to the retractable pivot shaft 6. In other words, the elastic member 71 in this embodiment is configured so that the direction and strength of the force pressing against the leading boom 33 can be adjusted by changing the installation position of the pressing force adjustment plate 75.

[0038] The insertion groove 72 is a groove into which an insertion projection 73 is formed on either the leading boom 33 or the retractable pivot shaft 6. In this embodiment, as shown in Figure 4, it is formed on the base end side of the leading boom 33, below the pivot support that is pivotally supported by the retractable pivot shaft 6. Furthermore, the insertion groove 72 is formed as a recessed groove with a substantially semicircular cross-section that curves upward, so that the insertion projection 73 that has been inserted can escape along its inner wall surface when the leading boom 33 rotates by a predetermined angle.

[0039] Furthermore, the cross-sectional shape of the insertion groove 72 is not limited to a substantially semicircular shape, but may be appropriately selected from cross-sectional shapes that allow the insertion protrusion 73 to escape.

[0040] The engaging projection 73 is fitted into the engaging groove 72 and disengages from the engaging groove 72 when a force of a predetermined strength or greater is applied to the leading edge boom 33 in the front-rear direction. In this embodiment, the engaging groove 72 is formed on either the leading edge boom 33, where it is not formed, or the retractable pivot shaft 6. In this embodiment, since the engaging groove 72 is formed on the leading edge boom 33, the engaging projection 73 is formed on the retractable pivot shaft 6.

[0041] Specifically, as shown in Figures 4 and 5, the insertion projection 73 is formed in a cylindrical shape that can be inserted into the insertion groove 72, and is formed to protrude from the outer circumferential surface of the retractable pivot shaft 6 in a direction perpendicular to the retractable pivot shaft 6.

[0042] The shape of the insertion projection 73 is not limited to a cylindrical shape, but may be appropriately selected from shapes that can be inserted into the insertion groove 72 and can be removed from the insertion groove 72 by a force greater than a predetermined strength against the leading edge boom 33.

[0043] The automatic return slope 74 is a slope that automatically returns the leading edge boom 33, which has been rotated and retracted, to its position before retraction by guiding the engagement projection 73 along its slope, and is formed in a downward slope towards the engagement groove 72.

[0044] In this embodiment, the automatic return slope 74 is formed as an inclined surface having a gradient along a spiral trajectory in which the amount of axial movement is constant in proportion to the amount of rotation of the leading boom 33, in the direction in which the engaging projection 73 escapes from the engaging groove 72 when it rotates and retracts (to the right of the engaging groove 72 in Figures 4 and 5).

[0045] This automatic return slope 74 allows for adjustment of the speed at which the leading boom 33 is automatically returned by varying the gradient. In other words, as shown in Figure 6, the speed of automatic return can be increased by making the gradient steeper than that of this embodiment.

[0046] Furthermore, a rotation stopper 76 is formed on the tip of the automatic return slope 74 and on the side opposite to the automatic return slope 74 (to the left of the insertion groove 72 in Figures 4 and 5) relative to the insertion groove 72, which limits the angle at which the leading boom 33 rotates and retracts. In this embodiment, the rotation stopper 76 is configured as a wall surface of a height that the insertion protrusion 73 cannot overcome when the leading boom 33 rotates. In other words, by adjusting the spacing of these rotation stoppers 76, the angle at which the leading boom 33 rotates and retracts can be set.

[0047] Furthermore, the automatic return ramp 74 is not limited to being formed in one rotational direction relative to the engagement groove 72, but may be formed in both rotational directions as shown in Figure 7.

[0048] Next, the operation of each component in the boom sprayer 1 of this embodiment will be described.

[0049] As shown in Figure 1, the boom sprayer 1 of this embodiment sprays chemicals while traveling with the side booms 3 extended. At this time, the engaging projection 73 of the clutch mechanism 7 is engaged in the engaging groove 72, as shown in Figures 4 and 8(a).

[0050] This section explains what happens when the leading boom 33 is subjected to weak forces that do not cause damage to the side booms 3, such as collisions with crops or light contact with the ground, or when it is subjected to changes in the speed of a passing vehicle or vibrations caused by uneven road surfaces.

[0051] In this case, the leading boom 33 attempts to rotate to the rear side when subjected to force. However, the leading boom 33 is held in place below the retractable pivot shaft 6 by the elastic member 71, and the engaging projection 73 cannot overcome the engaging groove 72 and therefore cannot escape. Thus, the leading boom 33 remains deployed without unintentionally rotating and retracting, preventing the creation of areas that are not sprayed due to weak forces or swaying.

[0052] Next, we will explain the case where the leading boom 33 is subjected to a strong force, such as a violent collision with the ground, causing damage to the side boom 3.

[0053] In this case, the leading boom 33 attempts to rotate towards the rear (opposite direction of travel) where it is subjected to force. The engaging projection 73 pushes the leading boom 33 upward against the elastic force of the elastic member 71 along the inner circumferential surface of the curved engaging groove 72. When the applied force exceeds a predetermined strength, the engaging projection 73 disengages from the engaging groove 72, as shown in Figures 5 and 8(b). As a result, the leading boom 33 becomes capable of rotating and retracting.

[0054] In this way, when a force exceeding a predetermined strength is applied to the leading boom 33, the leading boom 33 rotates and retracts, reducing the load on the side boom 3 and thus preventing damage.

[0055] In this embodiment, the leading boom 33 is formed such that the longitudinal length of the leading boom 33 on the tip side of the retraction pivot axis 6 is longer, so that the tip of the leading boom 33 can be retracted from the ground or the like with a small rotation angle.

[0056] Furthermore, since the retraction pivot shaft 6 is provided at an angle toward the tip of the leading boom 33, the leading boom 33 that rotates and retracts can move much further away from the ground compared to when it rotates and retracts around the vertical folding shaft 32, as shown in Figures 9(b) and 9(c). Therefore, the angle at which it rotates and retracts to prevent damage can be smaller, and the area that is not sprayed can be narrowed.

[0057] As shown in Figures 8(c) and 8(d), the leading boom 33 can rotate along the automatic return slope 74 until the engaging projection 73 reaches the position of the rotation stopper 76. In this way, an upper limit is set on the rotatable angle of the leading boom 33, so that the area that is not sprayed can be kept within a certain range.

[0058] Then, when the leading boom 33 is no longer subjected to force in the front-to-back direction, it automatically returns to its original deployed position. Specifically, the leading boom 33 is held in place downward by the elastic member 71. The automatic return slope 74 formed on the leading boom 33 is pressed against the engagement projection 73 by the elastic force of the elastic member 71. However, because the automatic return slope 74 is inclined, it receives a rotational reaction force from the engagement projection 73.

[0059] The leading boom 33 rotates in the return direction due to this reaction force. In this embodiment, the automatic return slope 74 is formed with a gradient that follows a spiral trajectory, so the force for returning is proportional to the amount of rotation, and the return operation can be started no matter where the leading boom 33 stops on the slope. In addition, in this embodiment, the retraction pivot shaft 6 is inclined, and the leading boom 33 rotates diagonally upward, so a return force due to its own weight is also obtained.

[0060] As shown in Figures 4 and 8(a), the leading boom 33 can rotate until the engaging projection 73 engages with the engaging groove 72, and then return to the deployed position.

[0061] Furthermore, the side boom 3 can be folded around the storage folding shaft 32 when storing it. In this embodiment, extending the telescopic cylinder 4 causes the link mechanism 5 to rotate the base end 34 of the leading boom 33 backward. At this time, since the link mechanism 5 rotates the base end 34, which is provided with the retractable pivot shaft 6, no force is applied in the forward direction to the leading boom 33 on the tip side of the retractable pivot shaft 6. Therefore, the leading boom 33 can be folded around the storage folding shaft 32 without rotating around the retractable pivot shaft 6.

[0062] According to this embodiment described above, the following effects can be achieved. 1. When a force is applied to the leading boom 33 in the forward or backward direction, the load on the side boom 3 can be suppressed and damage can be prevented by rotating and retracting the leading boom 33 in the direction of that force. 2. By tilting the retraction pivot shaft 6, the tip can be moved far away from the ground with a small rotational retraction angle, thereby narrowing the area that is not sprayed. 3. By providing a clutch mechanism 7 on the retractable pivot shaft 6, the deployed state can be maintained without rotating and retracting in the event of weak forces, speed changes, or shaking that do not cause damage, thereby stabilizing the spray width and amount. 4. The leading boom 33, which has been rotated and retracted, can be automatically returned to its pre-retraction position by the automatic return ramp 74 and its own weight. 5. Because the automatic return ramp 74 has a gradient that follows a spiral trajectory, the force required to return is proportional to the amount of rotation, and the return operation can be reliably initiated regardless of the rotational position at which the leading boom 33 stops.

[0063] It should be noted that the boom sprayer according to the present invention is not limited to the embodiments described above and can be modified as appropriate. For example, the elastic member 71 is composed of a coil spring, but is not limited thereto; it may be composed of rubber or the like, as long as it can be configured to press the leading boom 33 either up or down. Also, the gradient of the automatic return slope 74 is not limited to following a spiral trajectory, and the gradient may be changed in the middle of the slope. [Explanation of Symbols]

[0064] 1 Boom Sprayer 2 Center Boom 3 Side Booms 4. Telescopic cylinder 5 Link mechanism 6. Retractable pivot shaft 7. Clutch mechanism T-Towing Vehicle 31. Base boom 31a First base boom 31b Second base boom 32 Folding shaft for storage 33. Cutting-edge boom 34 Proximal end 71 Elastic members 72 Inset groove 73 Insertion protrusion 74 Automatic return ramp 75 Holding force adjustment plate 76 Rotation stopper

Claims

1. A boom sprayer equipped with side booms that can be folded when stored, The side boom comprises a base boom and a front boom located at the very tip of the side boom and supported by a retractable folding shaft provided at the tip of the base boom. The boom sprayer is provided with a retraction pivot shaft at the base end of the leading edge boom, located on the tip side of the retraction folding shaft, which rotates and retracts the leading edge boom in the direction of the force when a force is applied to the leading edge boom in the front-rear direction.

2. The boom sprayer according to claim 1, wherein the axial direction of the retractable pivot shaft is inclined from vertical toward the tip of the most advanced boom.

3. The boom sprayer according to claim 1 or 2, wherein the retractable pivot shaft is equipped with a clutch mechanism that rotates and retracts the leading edge boom in the direction of the force when a force of a predetermined strength or greater is applied to the leading edge boom in the front-rear direction.

4. The aforementioned cutting-edge boom, It is pivotally supported so as to be slidable in the axial direction along the aforementioned retractable pivot shaft, The aforementioned clutch mechanism is An elastic member that presses the leading boom either above or below the retractable pivot shaft, A recessed groove formed in either the aforementioned leading boom or the aforementioned retractable pivot shaft, A protruding part is formed on the other side where the aforementioned recess groove is not formed, and which fits into the aforementioned recess groove, and when the leading edge boom rotates to a predetermined angle, it escapes from the recess groove against the elastic force of the elastic member. A boom sprayer according to claim 3, having the following features.

5. The boom sprayer according to claim 4, wherein either the leading edge boom and the retractable pivot shaft, on which the engagement groove is formed, has an automatic return slope formed in a downward sloping manner toward the engagement groove to guide the engagement protrusion.

6. The boom sprayer according to claim 5, wherein the automatic return slope has a gradient along a spiral trajectory that results in a constant axial movement proportional to the amount of rotation of the leading boom.

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