Bed lifting device

Abstract

To provide a load carrying platform lifting unit capable of relatively suppressing a height of a load carrying platform lifting unit, and securing a required height of a load carrying platform when the same is lifted up.SOLUTION: A load carrying platform lifting unit comprises: a load carrying platform 6; support frames 11A, 11B; arms 13A, 13B; a rotary shaft part 52 for rotatably supporting the load carrying platform 6 in a direction where the same is tilted to a rear part; and actuators 12A, 12B whose lower ends are supported by the support frames 11A, 11B, and whose upper ends are supported by the load carrying platform 6, and which lift up and rotate the load carrying platform 6 by extension / shrinkage. The actuators 12A, 12B lift up the load carrying platform 6 by extension, for arranging the load carrying platform 6 on a lifted position to which arms 13A, 13B slide and which is an upper limit position, and at the lifted position of the load carrying platform 6, by further extension of the actuators 12A, 12B, the load carrying platform 6 is rotated around the rotary shaft part 52 as a center of rotary, for arranging the load carrying platform 6 in a posture state at which the load carrying platform is tilted to a rear part.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a loading platform lifting and lowering device that lifts and rotates a loading platform. [Background technology]

[0002] One such bed lifting device has been disclosed, which includes a frame that supports the bed via a link mechanism to tilt it sideways for unloading, a so-called side dump; slide rotation support sections that are arranged at the front and rear of the bed and that raise and lower the bed as well as rotate it; and an extendable actuator (see Patent Document 1). This bed lifting device uses a long hole as the fixed portion of the bed's rotation shaft, and when the bed is raised by the actuator, the rotation shaft slides up through the long hole, allowing the load to be discharged from the bed from a position higher by the length of the long hole. Another device has been disclosed that includes a support body that is provided vertically at the rear end of the vehicle body, a guide member that rises and falls along the support body, and a hydraulic cylinder, where the guide member rotatably supports the rear end of the bed, and the bed is raised and lowered by the extension and contraction of the hydraulic cylinder (see Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-112903 [Patent Document 2] Japanese Patent Application Publication No. 58-431 Summary of the Invention [Problem to be solved by the invention]

[0004] In the bed lifting device described in Patent Document 1, for example, when the bed is rotated to load a load on a transport vehicle such as a truck, the open end of the bucket may lower and come into contact with the tailgate of the transport vehicle. Furthermore, when the bed is raised, the top of the bed lowers, which could cause the top of the bed to interfere with the top of the tailgate. Furthermore, the height of the top of the bed of the bed lifting device increases by the length of the elongated hole in the bed, which could cause the harvester equipped with the bed lifting device to exceed the maximum load height when loaded onto a transport vehicle and moved, or make it impossible to store the harvester in an agricultural machinery shed.

[0005] Furthermore, in the bed lifting device described in Patent Document 2, the height to the top of the bed of the bed lifting device is increased by the height of the support body installed vertically at the rear end of the vehicle body, which means that when a harvester equipped with the bed lifting device is loaded onto a transport vehicle and moved, there is a risk that the upper limit of the loadable height may be exceeded, or the harvester may not be able to be stored in an agricultural machinery shed.

[0006] To solve such problems, the present invention aims to provide a loading platform lifting device that can keep the height of the loading platform lifting device itself relatively low and ensure the required height of the loading platform when the loading platform is raised. [Means for solving the problem]

[0007] (1) The loading platform lifting device of the present invention comprises a loading platform, support frames arranged in positions facing each other with the loading platform in between, an arm protruding upward from the support frame and supported so as to be able to slide up and down, a pivot shaft portion provided at the tip of the arm and supporting the loading platform so as to be able to pivot around the tip of the arm as a pivot center in a direction tilting the loading platform toward the rear of the loading platform, and an actuator arranged at a position further forward of the loading platform than the arm, with its lower end supported by the support frame and its upper end supported by the loading platform, and which raises, lowers, and rotates the loading platform by extending and contracting, wherein the actuator raises the loading platform by extending the actuator and slides the arm to position the loading platform at an upper limit raised position, and at the raised position of the loading platform, further extension of the actuator rotates the loading platform around the pivot shaft portion as a pivot center, positioning the loading platform in a position tilted toward the rear of the loading platform.

[0008] (2) The loading platform lifting device according to the present invention is characterized in that the upper end of the actuator is supported between the center of gravity of the loading platform and the pivot shaft portion.

[0009] (3) The loading platform lifting device of the present invention is characterized by having a lifting guide that supports the loading platform, which rises and falls due to the extension and contraction of the actuator, in a constant posture and guides it between the lowered position and the raised position.

[0010] (4) The loading platform lifting device of the present invention is characterized in that the arm has a plurality of upper limit positioning holes at predetermined intervals in the sliding movement direction, the support frame has a long hole in the sliding movement direction of the arm through which the plurality of upper limit positioning holes are exposed, and a positioning pin is inserted into one of the plurality of upper limit positioning holes through the long hole.

[0011] (1) With the bed lifting device according to the present invention, the bed can be raised by extending the actuator, and the bed can be raised to a raised position while maintaining this posture by sliding the arm upward. Then, when the bed reaches the raised position, the actuator can be further extended to rotate the bed about the pivot shaft, placing the bed in a tilted rearward posture. This allows, for example, the bed to be raised with a load on it, and then rotated rearward in the raised position to eject the load from the rear of the bed. Then, the actuator retracts due to the weight of the bed or the actuator's operation, rotating the bed about the pivot shaft and changing the bed from its tilted rearward posture to a horizontal posture. Then, the actuator retracts further, causing the arm to slide downward, returning the bed, actuator, and arm to their original positions, making the bed ready for loading.

[0012] (2) In the bed lifting device according to the present invention, the upper end of the actuator is supported between the center of gravity of the bed and the pivot shaft. Therefore, when the actuator is extended, the bed can be first raised and then rotated toward the rear of the bed at the raised position. When the actuator is retracted, the bed can be first rotated to a horizontal position at the raised position and then lowered.

[0013] (3) The platform lifting device according to the present invention has a lifting guide that supports the platform, which rises and falls due to the extension and contraction of the actuator, in a constant position and guides it between the lowered and raised positions. This configuration prevents the platform from rotating while it is being raised or lowered, and maintains a stable position.

[0014] (4) In the loading platform lifting device of the present invention, the arm is provided with a plurality of upper limit positioning holes at predetermined intervals in the sliding movement direction, and the support frame is provided with an elongated hole that exposes the plurality of upper limit positioning holes along the sliding movement direction of the arm, and a positioning pin is inserted into one of the plurality of upper limit positioning holes through the elongated hole.

[0015] With this configuration, the positioning pin rises and falls within the insertion hole as the arm rises and falls, and at the same time the pivot shaft of the arm reaches a predetermined raised position, the positioning pin abuts against the inner wall at the upper end of the elongated hole. When the positioning pin abuts against the inner wall at the upper end of the elongated hole, the positioning pin is prevented from rising, and the arm is prevented from rising. Because the positioning pin can adjust the upper limit position of the arm, the height to which the loading platform rises can be adjusted according to the height of the transport vehicle carrying the load. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a loading platform lifting device that can lift the loading platform to a required height and tilt it backward in the lifted position to discharge the loaded items. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a side view of a harvester equipped with a bed lifting device according to an embodiment of the present invention; [Figure 2] 1 is a front view of a loading platform lifting device according to an embodiment of the present invention, showing a state in which the loading platform is lowered to the lowest position. [Figure 3] 3A and 3B are diagrams of a loading platform lifting device according to an embodiment of the present invention, showing a state in which the loading platform is lowered to the lowest position, with FIG. 3A being a plan view and FIG. 3B being a left side view. [Figure 4] 3(b) is a cross-sectional view of the loading platform lifting and lowering device according to the embodiment of the present invention taken along the line CC in FIG. [Figure 5] 1 is a perspective view of a loading platform lifting device according to an embodiment of the present invention, showing a state in which the loading platform is lowered to the lowest position. [Figure 6] 1 is an exploded perspective view of a loading platform lifting device according to an embodiment of the present invention; [Figure 7]7A and 7B are cross-sectional views of the loading platform lifting and lowering device according to the embodiment of the present invention, with FIG. 7A showing the AA cross section in FIG. 2 and FIG. 7B showing the BB cross section in FIG. [Figure 8] 8A and 8B are diagrams showing a loading platform lifting device according to an embodiment of the present invention, illustrating a state in which the loading platform is in the middle of being lifted, with FIG. 8A being a left side view and FIG. 8B being a front view. [Figure 9] 1 is a perspective view of a loading platform lifting device according to an embodiment of the present invention, showing a state in which the loading platform is in the middle of being lifted; [Figure 10] 10A and 10B are diagrams of a loading platform lifting device according to an embodiment of the present invention, showing a state in which the loading platform is raised to the uppermost position, with FIG. 10A being a left side view and FIG. 10B being a front view. [Figure 11] 1 is a perspective view of a loading platform lifting device according to an embodiment of the present invention, showing a state in which the loading platform is raised to the uppermost position. [Figure 12] 1 is a side view of a platform lifting device according to an embodiment of the present invention, showing a platform loaded with agricultural produce raised to its uppermost position and dropping the agricultural produce onto a truck. FIG. [Figure 13] 1 is a perspective view of a platform lifting device according to an embodiment of the present invention, showing a platform loaded with agricultural products raised to its uppermost position and dropping the agricultural products onto a truck. DETAILED DESCRIPTION OF THE INVENTION

[0018] A bed lifting / lowering device 7 according to an embodiment in which the bed lifting / lowering device according to the present invention is applied to a harvester 1 will be described with reference to the drawings.

[0019] First, the configuration of the harvester 1 equipped with the platform lifting device 7 according to this embodiment will be described. As shown in Figure 1, the harvester 1 is composed of a vehicle body 2, a traveling device 3, a driving device 4, a harvesting device 5, a loading platform 6, a loading platform lifting device 7, and an operating unit (not shown) that operates the lifting and lowering of the loading platform 6 using the loading platform lifting device 7.

[0020] Harvesting machine 1 is configured to harvest crops such as rice and corn planted in a field while traveling, shred the crops, and load them onto loading platform 6, which is then loaded onto a transport vehicle such as a 2-ton truck or a 4-ton truck. The harvested crops are used, for example, as livestock feed, and are transported by the transport vehicle to a feed base.

[0021] The vehicle body 2 is, for example, a frame structure vehicle body having a frame connected by highly rigid vertical and horizontal frames, and is configured to support each component. The traveling device 3 is connected to the vehicle body 2 and is configured by endless tracks that are rotationally driven to absorb unevenness in rough traveling surfaces such as farm fields and to enable turning and steering in forward, backward, left and right directions.

[0022] The driving device 4 is fixed to the front of the vehicle body 2 and includes a steering mechanism (not shown) such as a steering handle for steering the traveling device 3. The harvesting device 5 is configured to cut and shred agricultural crops planted in the field and discharge the shredded crops into a loading platform 6.

[0023] As shown in Figure 1, the loading platform 6 is disposed behind the driving device 4 of the harvester 1, and is composed of a box body 6a with an open top in the vertical direction when in a horizontal position, and left and right sliding bodies 6b fixed to the box body 6a and sliding relative to the loading platform lifting device 7, as shown in Figures 3(a), 3(b), 5, 7(b), and 9. As shown in Figures 2, 3(a), 3(b), and 5, the loading platform 6 is connected to the loading platform lifting device 7 and is configured to be raised and lowered and rotated by the loading platform lifting device 7. Agricultural products harvested by the harvesting device 5 are loaded onto the loading platform 6.

[0024] As shown in FIG. 1, the bed lifting device 7 is fixed to the rear of the body 2 of the harvester 1, and as shown in FIGS. 2, 3(a), 3(b), and 6, is composed of support frames 11A and 11B, actuators 12A and 12B, arms 13A and 13B, guide rollers 14A and 14B, lifting guides 15A and 15B, and a controller (not shown). In the following description, the terms "upper" and "lower" refer to the upper and lower sides of the harvester 1 when the bed lifting device 7 is mounted on the harvester 1 shown in FIG. 1, and the terms "left" and "right" refer to the left and right sides as viewed from the rear of the harvester 1. Although the bed lifting device 7 is composed of support frames 11A and 11B, the bed lifting device according to the present invention may be composed of a single support frame.

[0025] As shown in Fig. 5, the support frame 11A is attached to the left side surface portion, which serves as one side surface portion, of the cargo bed 6. As shown in Fig. 6, the support frame 11A is made up of a left side panel 21, a right side panel 22, a left reinforcing panel 23, a right reinforcing panel 24, a left reinforcing frame 25, a right reinforcing frame 26, connecting members 27 and 28, an upper connecting member 31, and a lower connecting member 32. Each component is made of a metal material and has high mechanical strength.

[0026] The left side plate 21 is made up of a support portion that extends in the vertical direction and supports the actuator 12A and the arm 13A, and an attachment portion that extends perpendicular to the vertical direction and is attached to the body 2 of the harvester 1. Four attachment holes 21a for attaching upper guide rollers 61 (described later) of the guide roller 14A and four attachment holes 21b for attaching lower guide rollers 62 are formed through the support portion of the left side plate 21.

[0027] Further, an elongated hole 21c for inserting the left reinforcing frame 25 and a mounting hole 21d for attaching the actuator 12A are formed through the support portion of the left side plate 21. Three mounting holes 21e for attaching the support frame 11A to the vehicle body 2 and three fixing holes 21f for fixing the lower connecting member 32 are formed through the mounting portion of the left side plate 21.

[0028] Similar to the left side plate 21, the right side plate 22 is made up of a support portion that extends in the vertical direction and supports the actuator 12A and the arm 13A, and an attachment portion that extends perpendicular to the vertical direction and is attached to the body 2 of the harvester 1. Four attachment holes 22a for attaching upper guide rollers 61 (described later) of the guide roller 14A and four attachment holes 22b for attaching lower guide rollers 62 are formed through the support portion of the right side plate 22.

[0029] Further, an elongated hole 22c for inserting the right reinforcing frame 26 and a mounting hole 22d for attaching the actuator 12A are formed through the support portion of the right side plate 22. Three mounting holes 22e for attaching the support frame 11A to the vehicle body 2 and three fixing holes 22f for fixing the lower connecting member 32 are formed through the mounting portion of the right side plate 22.

[0030] The left reinforcing plate 23 is formed in a substantially triangular shape, and has a mounting hole 23a formed therethrough for mounting the actuator 12A. The left reinforcing plate 23 is joined to the side surface of the left side plate 21 facing the right side plate 22 by joining means such as welding.

[0031] The right reinforcing plate 24 is formed in a substantially triangular shape, similar to the left reinforcing plate 23, and has a mounting hole 24a formed therethrough for mounting the actuator 12A. The right reinforcing plate 24 is joined to the side surface of the right side plate 22 facing the left side plate 21 by joining means such as welding.

[0032] Left reinforcing frame 25 has semicircular longitudinal ends, and elongated holes 25a are formed therethrough, into which positioning pins 54 of arm 13A (described later) are inserted. Left reinforcing frame 25 is inserted into elongated holes 21c in left side plate 21, and joined to left side plate 21 by joining means such as welding.

[0033] Like the left reinforcing frame 25, the right reinforcing frame 26 has both longitudinal ends formed in a semicircular shape and has elongated holes 26a formed therethrough into which positioning pins 54 of the arm 13A, which will be described later, are inserted. The right reinforcing frame 26 is inserted into elongated holes 22c in the right side plate 22 and joined to the right side plate 22 by joining means such as welding.

[0034] As shown in FIGS. 4 and 6 , the connecting member 27 is made of a channel steel material having a U-shaped cross section and is joined by welding or other joining means to the side of the left side plate 21 that faces the right side plate 22. The connecting member 27 is provided to extend vertically along the edge of the left side plate 21 and connects the left side plate 21 and the right side plate 22 together. The connecting member 28 is a mirror image of the connecting member 27 and is formed in the same manner. It is disposed opposite the connecting member 27 and is joined by welding or other joining means to the side of the right side plate 22 that faces the left side plate 21. The connecting member 28 is also provided to extend vertically along the edge of the right side plate 22 and connects the left side plate 21 and the right side plate 22 together. Note that the connecting member 28 may be formed in the same shape as the connecting member 27.

[0035] The upper connecting member 31 is made of a rectangular plate material and has a rectangular through-hole 31a formed therein for passing the arm 13A therethrough. The upper connecting member 31 connects the upper end of the support portion of the left side plate 21 that supports the arm 13A to the upper end of the support portion of the right side plate 22 that supports the arm 13A. The upper connecting member 31 is joined to the upper end of the left side plate 21 and the upper end of the right side plate 22 by joining means such as welding.

[0036] The lower connecting member 32 is made of a rectangular rod-shaped member, and has a plurality of through-holes 32a formed on its side surface for passing fastening members (not shown). The lower connecting member 32 connects the left side plate 21 and the right side plate 22 by passing fastening members (not shown) through fixing holes 21f in the mounting portion of the left side plate 21 and fixing holes 22f in the mounting portion of the right side plate 22.

[0037] 5, the support frame 11B is attached to the right side surface, which is the other side surface of the loading platform 6, and is configured similarly to the support frame 11A. The support frame 11B is fixed to the vehicle body 2 of the harvester 1.

[0038] 5, the actuator 12A is a mechanism, such as a hydraulic mechanism, that extends and retracts to raise and lower the platform 6, and is connected to a controller, so that the lifting and lowering operation is controlled by the controller. The actuator 12A is configured to extend when hydraulic pressure is supplied and to retract due to the weight of the platform 6.

[0039] The actuator 12A has a stroke that causes the platform 6 to rotate around the rotation shaft 52 by further extending when the tip of the arm 13A reaches a predetermined upper limit position.

[0040] 6, the actuator 12A is composed of a hydraulic cylinder 41, a piston rod 42, an upper end support part 43 connected to the left side part of the platform 6, a fixing pin 44, a pin fixing tool 45, and a hydraulic pressure supply device (not shown). The hydraulic pressure supply device is connected to a controller, and is configured so that the hydraulic pressure supply is controlled by the controller.

[0041] The hydraulic cylinder 41 is formed in a cylindrical shape and houses a piston rod 42 so that it can move back and forth. A single-acting hydraulic cylinder is used in which hydraulic pressure is supplied from a hydraulic supply device to extend the piston rod 42. The piston rod 42 of the hydraulic cylinder 41 is retracted by the weight of the loading platform 6. In this embodiment, a single-acting hydraulic cylinder 41 is used, but a double-acting hydraulic cylinder in which the piston rod 42 is extended and retracted by the supply of hydraulic pressure may also be used. A single-acting hydraulic cylinder can simplify the configuration of the hydraulic circuit compared to a double-acting hydraulic cylinder. An insertion hole 41a for inserting a fixing pin 44 is formed through the bottom of the hydraulic cylinder 41, and the hydraulic cylinder 41 is rotatably supported on the support frame 11A via the fixing pin 44 inserted into the insertion hole 41a.

[0042] The piston rod 42 is connected at its upper end to an upper end support portion 43 that supports the loading platform 6 so that it can rotate freely, and the reciprocating movement of the piston rod 42 is transmitted to the loading platform 6 via the upper end support portion 43, causing the loading platform 6 to rise and fall.

[0043] The upper end support part 43 is composed of a fixed part 43a fixed to the loading platform 6, a connecting part 43b connected to the upper end of the piston rod 42, and a connecting pin 43c connecting the fixed part 43a and the connecting part 43b so that they can rotate freely relative to each other. As the piston rod 42 extends and contracts, the connecting part 43b rotates relative to the fixed part 43a.

[0044] Like actuator 12A, actuator 12B is a hydraulic mechanism and is connected to a controller so that its extension and contraction operations are controlled by the controller. Actuator 12B is composed of a hydraulic cylinder 41, a piston rod 42, a pin fixing device 45, and a hydraulic pressure supply device (not shown). The hydraulic pressure supply device is connected to the controller so that the hydraulic pressure supply is controlled by the controller.

[0045] 5 and 6, arm 13A has a main body 51, a pivot shaft 52, and a flange 53. Main body 51 of arm 13A is provided with a positioning hole 51a into which a positioning pin 54 is inserted through elongated hole 25a of left reinforcing frame 25. When arm 13A slides upward and positioning pin 54 abuts against the inner wall of the upper end of elongated hole 25a, it reaches the upper limit of its movement and is prevented from sliding further upward.

[0046] That is, when the actuator 12A extends and the platform 6 starts to rise, the arm 13A slides upward accordingly. When the actuator 12A contracts and the platform 6 starts to descend, the arm 13A slides downward accordingly.

[0047] The main body 51 is made of a rod-shaped member with a square cross section, and has a plurality of upper limit positioning holes 51a formed at the bottom thereof, through which positioning pins 54 are inserted. The plurality of upper limit positioning holes 51a are provided at predetermined intervals in the longitudinal direction of the main body 51, and the positioning pins 54 can be inserted through the elongated holes 25a of the left reinforcing frame 25.

[0048] The pivot shaft portion 52 is composed of a fixed portion 52a fixed to the loading platform 6, a connecting portion 52b connected to the upper end of the main body 51, and a connecting pin 52c connecting the fixed portion 52a and the connecting portion 52b so that they can rotate freely relative to each other.

[0049] The flange 53 is made of a rectangular plate material and has the same shape as the upper connecting member 31 of the support frame 11A. The flange 53 is joined to the upper end of the main body 51 by welding or other joining means, and the connecting portion 52b of the rotating shaft portion 52 is fixed to the upper surface of the flange 53. The flange 53 is sized to abut against the upper connecting member 31 of the support frame 11A and close the through-hole 31a when the main body 51 is lowered, in order to prevent foreign matter such as straw from entering through the gap between the main body 51 and the through-hole 31a of the upper connecting member 31.

[0050] The positioning pin 54 is made of a rod-shaped member with a circular cross section, and is inserted into one of the plurality of upper limit positioning holes 51a in the main body 51 through the elongated hole 25a in the left reinforcing frame 25. The positioning pin 54 is in a state in which its tip portion passes through the upper limit positioning hole 51a and is positioned in the elongated hole 26a in the right reinforcing frame 26, its central portion is positioned in one of the plurality of upper limit positioning holes 51a, and its base end portion is positioned in the elongated hole 25a in the left reinforcing frame 25.

[0051] When the main body 51 slides upward, the positioning pin 54 simultaneously abuts against the inner wall at the upper end of the elongated hole 25a in the left reinforcing frame 25 and the inner wall at the upper end of the elongated hole 26a in the right reinforcing frame 26, thereby preventing the main body 51 from rising. When the positioning pin 54 is inserted into the lowermost upper limit positioning hole 51a out of the multiple upper limit positioning holes 51a in the main body 51, the distance over which the positioning pin 54 abuts against the inner wall at the upper end of the elongated hole 25a in the left reinforcing frame 25 and the inner wall at the upper end of the elongated hole 26a in the right reinforcing frame 26 is the longest, allowing the main body 51 to slide to the highest position.

[0052] Conversely, when the positioning pin 54 is inserted into the uppermost upper limit positioning hole 51a among the plurality of upper limit positioning holes 51a in the main body 51, the distance until the positioning pin 54 abuts against the inner wall at the upper end of the elongated hole 25a in the left reinforcing frame 25 and the inner wall at the upper end of the elongated hole 26a in the right reinforcing frame 26 is the shortest, and the main body 51 can be prevented from rising at its lowest position. In other words, by selecting the position of the plurality of upper limit positioning holes 51a into which the positioning pin 54 is inserted, the upper limit position of the main body 51 can be adjusted by sliding it.

[0053] For example, when unloading a load from the loading platform 6 onto the loading platform of a transport vehicle such as a 2-ton truck with a relatively low vehicle height, the positioning pin 54 is inserted into the uppermost upper limit positioning hole 51a of the plurality of upper limit positioning holes 51a of the main body 51. On the other hand, when unloading a load from the loading platform 6 onto the loading platform of a transport vehicle such as a 4-ton truck with a relatively high vehicle height, the positioning pin 54 is inserted into the lowermost upper limit positioning hole 51a of the plurality of upper limit positioning holes 51a of the main body 51.

[0054] Like arm 13A, arm 13B has a main body 51, a pivot shaft 52, and a flange 53. When main body 51 of arm 13B starts to slide upward and positioning pin 54 abuts against the inner wall of the upper end of elongated hole 26a, arm 13B reaches the upper limit of its movement and is prevented from sliding further upward.

[0055] 2, 6, and 7(a), the guide roller 14A is made up of an upper guide roller 61 and a lower guide roller 62. The upper guide roller 61 is made up of four rollers, and each roller is rotatably attached with both ends supported by the mounting holes 21a in the left plate 21 and the mounting holes 22a in the right plate 22. The rollers abut against the side of the main body 51 of the arm 13A, guiding the main body 51 so that it can slide up and down.

[0056] The lower guide rollers 62, like the upper guide rollers 61, are made up of four rollers, and each roller is rotatably attached with both ends supported by the mounting holes 21b of the left side plate 21 and the mounting holes 22b of the right side plate 22. The lower guide rollers 62 come into contact with the side surfaces of the main body 51 of the arm 13A, and guide the main body 51 so that it can slide up and down.

[0057] The lower guide roller 62 is spaced apart from the upper guide roller 61 in the direction of movement of the main body 51 and is located below the arm 13A. The upper guide rollers 61 and the lower guide rollers 62 may each be two, not four, or six or more. The guide roller 14B has the same configuration as the guide roller 14A.

[0058] 2 and 6, the lifting guide 15A is made up of an attachment portion 71 and a guide portion 72, and is joined to the right surface of the right side plate 22 of the actuator 12A at the attachment portion 71 by joining means such as welding. The guide portion 72 abuts against a sliding body 6b provided on the loading platform 6 and guides the sliding body 6b while the loading platform 6 is being raised or lowered. By guiding the sliding of the sliding body 6b, the lifting guide 15A maintains the posture of the loading platform 6 in a horizontal posture perpendicular to the vertical direction when the loading platform 6 is being raised or lowered.

[0059] Like the lifting guide 15A, the lifting guide 15B is composed of an attachment portion 71 and a guide portion 72, and as shown in Figures 5 and 7(b), the attachment portion 71 is joined to the left side surface of the left side plate 21 of the actuator 12B by joining means such as welding.

[0060] The controller is configured by a known microcomputer having a memory such as a ROM that stores setting value information such as calculation programs and data, and a processor that executes processing according to the program. The controller is connected to the hydraulic supply device for the actuators 12A, 12B, and controls the hydraulic supply operation of the hydraulic supply device to control the lifting and lowering operation of the actuators 12A, 12B. The controller may also be configured by a relay circuit.

[0061] The lifting and lowering operations of the loading platform lifting and lowering device 7 according to this embodiment and the loading operations onto the truck will be briefly described with reference to the drawings.

[0062] When the loading platform 6 of the harvester 1 is filled with harvested crops, the harvester 1 travels to a place where the load is discharged, such as an access road to the field, and stops at a position close to a transport vehicle, such as a 2-ton truck or a 4-ton truck, that transports the load discharged from the loading platform 6, and at a position suitable for loading the load on the loading platform 6 onto the loading platform of the transport vehicle.

[0063] When the harvester 1 is stopped and an operation to start operation of the platform lifting device 7 is performed on the operating unit of the harvester 1, the controller of the platform lifting device 7 supplies hydraulic pressure from the hydraulic supply device to the actuators 12A, 12B, and the extension of the piston rod 42 begins. When the piston rod 42 extends, the platform 6 rises. The left and right sliding bodies 6b of the platform 6 are guided by the lifting guides 15A, 15B, respectively, and the platform 6 rises while maintaining a horizontal position.

[0064] 8(a), 8(b), and 9, arms 13A and 13B slide upward as bed 6 rises. As arms 13A and 13B slide upward, positioning pin 54 simultaneously comes into contact with the inner wall at the upper end of elongated hole 25a in left reinforcing frame 25 and the inner wall at the upper end of elongated hole 26a in right reinforcing frame 26, preventing arms 13A and 13B from sliding upward and holding bed 6 in the raised position.

[0065] With the loading platform 6 in the raised position, the actuators 12A and 12B continue to extend.

[0066] The extension of actuators 12A, 12B causes bed 6 to rotate toward the rear of the bed around pivot shaft 52. As shown in Figure 11, the extension of actuators 12A, 12B stops and the rotation of bed 6 stops at a position where upper end support portion 43 does not pass in the rotation direction across vertical line L that passes through the rotation center of pivot shaft 52 shown in Figure 10(a). When bed 6 rotates and assumes a position where it is tilted toward the rear, the produce in bed 6 falls into the center of the bed of the transport vehicle, such as a 4-ton truck, as shown in Figures 12 and 13.

[0067] When the agricultural products in the loading platform 6 fall into the loading platform of a transport vehicle such as a 4-ton truck and an operation to start the return movement of the loading platform lifting device 7 is performed on the control unit of the harvester 1, actuators 12A and 12B contract and rotate in a direction to return the loading platform 6 to a horizontal position. Then, when the loading platform 6 is returned to the horizontal position at the raised position, further contraction of actuators 12A and 12B causes the left and right sliding bodies 6b of the loading platform 6 to be guided by lifting guides 15A and 15B, respectively, and the loading platform 6 descends while maintaining its horizontal position, returning to the original position shown in Figures 3(a), 3(b), and 5, and the lifting movement of the loading platform lifting device 7 ends.

[0068] The effects of the platform lifting and lowering device 7 according to this embodiment will be described with reference to the drawings. (1) The loading platform lifting device 7 of the embodiment comprises a loading platform 6, support frames 11A and 11B arranged in positions facing each other across the loading platform 6, arms 13A and 13B protruding upward from the support frames 11A and 11B and supported so as to be able to slide up and down, a pivot shaft portion 52 provided at the tip of the arms 13A and 13B and supporting the loading platform 6 so as to be able to rotate in a direction tilting the loading platform 6 toward the rear of the loading platform, with the tip of the arms 13A and 13B as the center of rotation, and actuators 12A and 12B arranged at a position further forward from the loading platform 6 than the arms 13A and 13B, with their lower ends supported by the support frames 11A and 11B and their upper ends supported by the loading platform 6, and which raise and lower and rotate the loading platform 6 by extending and contracting. The actuators 12A and 12B are configured to raise the loading platform 6 by extending the actuators 12A and 12B, and position the loading platform 6 at its upper limit raised position as the arms 13A and 13B slide. At the raised position of the loading platform 6, the actuators 12A and 12B are further extended to rotate the loading platform 6 around the pivot shaft 52 as the center of rotation, and position the loading platform 6 in a tilted position toward the rear of the loading platform.

[0069] Therefore, all of the cargo loaded on the loading platform 6 can be removed from the loading platform 6. When all of the cargo loaded on the loading platform 6 has been removed from the loading platform 6, the actuators 12A and 12B contract, causing the loading platform 6 to rotate in the returning direction around the rotation shaft 52 as the rotation center, and return to a horizontal posture. Then, the actuators 12A and 12B are further contracted, causing the arms 13A and 13B to slide downward, returning the loading platform 6 to its original lowered position, and making it possible to load cargo.

[0070] As a result, when the loading platform 6 is raised, the agricultural products can be dropped from a higher position and closer to the center of the loading platform 6. In addition, since the arm can be slid up and down, the height of the loading platform lifting device 7 itself can be kept relatively low by sliding it downward.

[0071] (2) In the loading platform lifting device 7 according to this embodiment, the upper end support portions 43 of the actuators 12A, 12B are supported between the center of gravity of the loading platform 6 and the pivot shaft portion 52. This configuration makes it possible to prevent the loading platform 6 from rotating about the pivot shaft portion 52 before it rises when the actuators 12A, 12B are extended with the loading platform 6 in the lowered position.

[0072] (3) The platform lifting device 7 according to this embodiment has lifting guides 15A and 15B that support the platform 6, which rises and falls due to the extension and contraction of actuators 12A and 12B, in a constant position and guide it between the lowered and raised positions. With this configuration, when the platform 6 rises and falls, the platform 6 rises and falls while maintaining a horizontal position via the slider 6b. As a result, the platform 6 rises and falls in a stable position without swinging.

[0073] (4) The loading platform lifting device 7 of this embodiment can determine the upper limit of the upward sliding movement of the arms 13A and 13B by inserting the positioning pin 54 into any positioning hole 51a selected from multiple positioning holes 51a provided on the arms 13A and 13B.

[0074] As a result, the height of the loading platform 6 can be adjusted according to the height of the tailgate, width and height of the loading platform of the transport vehicle carrying the load to be discharged from the loading platform 6. This has the effect of enabling all the load in the loading platform 6 to be reliably discharged onto the loading platform of the transport vehicle according to the size of the transport vehicle, such as a 2-ton truck or a 4-ton truck.

[0075] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various design modifications can be made within the scope of the invention as set forth in the claims. [Explanation of symbols]

[0076] 1 harvester, 2 vehicle body, 3 traveling device, 4 driving device, 5 harvesting device, 6 loading platform, 6a box body, 6b sliding body, 7 loading platform lifting device, 11A, 11B support frame, 12A, 12B actuator, 13A, 13B arm, 14A, 14B guide roller, 15A, 15B lifting guide, 27, 28 connecting member, 51a upper limit positioning hole, 43 upper end support part, 51 main body, 52 rotating shaft part, 54 positioning pin, 61 upper guide roller, 62 lower guide roller

Claims

[Claim 1] The loading platform and support frames disposed in positions facing each other with the loading platform in between; an arm that protrudes upward from the support frame and is supported so as to be slidable up and down; a pivot shaft portion provided at the tip of the arm and supporting the loading platform rotatably in a direction tilting the loading platform toward the rear of the loading platform with the tip of the arm as a pivot center; an actuator that is disposed at a position further forward than the arm from the loading platform, has a lower end supported by the support frame and an upper end supported by the loading platform, and extends and contracts to raise and lower and rotate the loading platform; The actuator extends to raise the loading platform, and the arm slides to place the loading platform at an upper limit raised position. At the raised position of the loading platform, the actuator further extends to rotate the loading platform around the pivot shaft as a rotation center, and place the loading platform in a position inclined toward the rear of the loading platform. a lifting guide that supports the platform, which rises and falls due to the extension and contraction of the actuator, in a constant posture and guides it between a lowered position and an elevated position; The lifting guide is a guide portion provided on the support frame; A sliding body provided on the loading platform; Including, The loading platform lifting device, wherein the guide portion abuts against the sliding body and guides the sliding of the sliding body while the loading platform is being lifted or lowered.

Images