Suspension arm structure of folding arm type crane

Abstract

The utility model discloses a folding arm type crane jib structure, which relates to the technical field of crane jibs and comprises a first jib, a second jib and a limit device, the first jib and the second jib are both of cylindrical structures with two open ends, the second jib is transversely and slidably connected in the first jib, and the limit device is arranged in the second jib. A limiting gap is reserved between the front side of the interior of the first lifting arm and the front side of the second lifting arm, and the top of the right end of the first lifting arm is connected with the top of the left end of the second lifting arm through a linear driving mechanism; a limiting device is mounted in the middle of the front side of the left end of the first lifting arm, a front limiting block is mounted in the middle of the front side of the left end of the second lifting arm and corresponds to the limiting device, and a rear limiting block is mounted in the middle of the front side of the right end of the second lifting arm and corresponds to the limiting device; according to the folding arm type crane jib structure, the stroke of the hydraulic cylinder is reduced to a small extent in a mechanical limiting mode, the hydraulic cylinder is prevented from being damaged due to the fact that the piston in the hydraulic cylinder abuts against the head or the tail of the hydraulic cylinder, and it is guaranteed that the hydraulic cylinder is in a normal operation state all the time.

Description

Technical Field

[0001] The utility model relates to the technical field of crane booms, in particular to a folding-arm crane boom structure. Background Art

[0002] The boom of a folding-arm crane achieves reciprocating motion under load via an external hydraulic cylinder. Existing folding-arm cranes utilize hydraulic cylinder stroke control to extend and retract the boom. This means the boom stops when the piston in the hydraulic cylinder presses against the cylinder's head or tail. However, when the piston presses against the cylinder's head or tail, the actuation area is inevitably smaller than the cylinder's normal operating area. The industry's average actuation area for a hydraulic cylinder is approximately 70% of its normal operating area. Pushing heavy objects upward or retracting them at a negative angle are extremely common operating conditions for folding-arm cranes. Consequently, significant design redundancy is inherent in calculating the hydraulic cylinder's thrust or pull, leading to excessively high production costs. Furthermore, a piston pressing against the cylinder's head or tail can easily damage the cylinder. Utility Model Content

[0003] The technical problem to be solved by the utility model is to overcome the existing defects and provide a folding arm crane boom structure, in which the second boom realizes reciprocating motion through a linear drive mechanism installed on the first boom, and a limiting device for controlling the stroke of the second boom is installed on the first boom, and a front limit block and a rear limit block are fixedly connected to the second boom. The stroke of the hydraulic cylinder is reduced by a very small amount through mechanical limiting, so as to avoid the piston in the hydraulic cylinder pressing against the head or tail of the hydraulic cylinder and causing damage to the hydraulic cylinder, and ensure that the hydraulic cylinder is always in normal operating state. The limiting scheme is simple and reliable, and the thrust or pulling force required by the hydraulic cylinder does not require a large design redundancy, which is conducive to reducing production costs and can effectively solve the problems in the background technology.

[0004] To achieve the above-mentioned object, the present invention provides the following technical solution: a folding arm crane boom structure, comprising a first boom, a second boom, and a limit device, wherein the first boom and the second boom are both cylindrical structures with open ends, the first boom is laterally slidably connected to the second boom, and a limit gap is left between the inner front side of the first boom and the front side of the second boom, and the top right end of the first boom is connected to the top left end of the second boom via a linear drive mechanism;

[0005] A limiting device is installed in the middle of the front left end of the first boom, a front limiting block is installed in the middle of the front left end of the second boom corresponding to the position of the limiting device, and a rear limiting block is installed in the middle of the front right end of the second boom corresponding to the position of the limiting device.

[0006] The operation of the linear drive mechanism can drive the second boom to move left and right relative to the first boom, so that the second boom can be extended or retracted into the first boom, completing the extension and retraction of the crane boom. The second boom continues to extend from the first boom, and eventually the rear limit block will be limited by the limit device to prevent the linear drive mechanism from extending to the limit of the hydraulic cylinder in itself. The second boom continues to retract into the first boom, and eventually the front limit block will be limited by the limit device to prevent the linear drive mechanism from shortening to the limit of the hydraulic cylinder in itself, thereby protecting the linear drive mechanism.

[0007] Furthermore, it also includes a reinforcement frame and a movable frame. The movable frame is installed on the top of the left end of the second boom through the reinforcement frame. The reinforcement frame is used to install the movable frame, and the movable frame is used to connect the linear drive mechanism.

[0008] Furthermore, the linear drive mechanism includes a hydraulic cylinder, the top right end of the boom 1 is movably connected to the fixed end of the hydraulic cylinder, and the telescopic end of the hydraulic cylinder is movably connected to the movable frame. The extension or contraction of the hydraulic cylinder can push the boom 2 to move left and right relative to the boom 1, thereby changing the length of the crane boom formed by the boom 1 and the boom 2. The limit device, the front limit block, the rear limit block, the boom 1 and the boom 2 cooperate to prevent the hydraulic cylinder from being extended to the longest state, causing the piston to press against the head of the hydraulic cylinder, and also to prevent the hydraulic cylinder from being shortened to the shortest state, causing the piston to press against the tail of the hydraulic cylinder, thereby preventing damage to the hydraulic cylinder. Since the piston no longer presses against the head or tail of the hydraulic cylinder, the hydraulic cylinder is always in a normal operating state and is in a normal operating area during operation. Therefore, the design of the hydraulic cylinder no longer requires large thrust or tension redundancy.

[0009] Furthermore, the linear drive mechanism further includes a support, a movable shaft 1 and a movable shaft 2, wherein the support is fixedly connected to the top of the right end of the boom 1, the support is movably connected to the fixed end of the hydraulic cylinder via the movable shaft 1, and the telescopic end of the hydraulic cylinder is movably connected to the movable frame via the movable shaft 2. The support and the movable shaft 1 cooperate to allow the fixed end of the hydraulic cylinder to be movably connected to the boom 1, and the movable shaft 2 and the movable frame cooperate to allow the telescopic end of the hydraulic cylinder to be movably connected to the boom 2, wherein the movable shaft 1 and the movable shaft 2 are arranged parallel to each other. Since both ends of the hydraulic cylinder are connected to the external structure in a movably connected manner, even if there is clearance when the boom 1 and the boom 2 are extended or retracted, the radial force on the hydraulic cylinder will be reduced, thereby preventing the hydraulic cylinder from being damaged due to the radial force.

[0010] Furthermore, the limiting device includes a screw, a limiting seat, and a limiting column. The middle portion of the left front end of the first boom is fixedly connected to the limiting seat via a screw. The limiting column is installed in the middle portion of the limiting seat. The rear end of the limiting column passes through the left front end of the first boom and extends into the limiting gap, and the rear end of the limiting column is located between the front and rear limiting blocks. The screw is used to install the limiting seat, and the limiting seat is used to install the limiting column. The setting of the limiting column avoids limiting the front and rear limiting blocks, allowing the second boom to slide left and right within a certain range within the first boom.

[0011] Furthermore, the limiting device also includes a transverse sliding column, a buffer spring and a buffer slider. A rectangular mounting groove is provided in the middle of the limiting seat, and two transverse sliding columns are fixedly connected in the rectangular mounting groove. The buffer slider is laterally slidably connected to the middle of the two transverse sliding columns, and a buffer spring is respectively sleeved on both ends of each transverse sliding column. A through groove is provided on the front side of the left end of the boom corresponding to the position of the rectangular mounting groove. The rear end of the buffer slider is fixedly connected to the front end of the limiting column, and the rear end of the limiting column passes through the through groove and extends into the limiting gap. When the second boom moves left and right relative to the first boom to the limit point, the front limit block and the rear limit block will hit the limit column as the boom moves, which can easily cause a large impact, causing the crane boom to vibrate and easily damage the limit column. Therefore, a buffer slider is provided. When the buffer slider moves left and right relative to the cross sliding column, it will be buffered by the buffer spring. Therefore, the limit column will also have a certain left and right buffer range, reducing the collision impact of the front limit block and the rear limit block with the limit column, reducing the vibration that may be generated by the crane boom, protecting the crane boom, and reducing the wear of the limit column.

[0012] Furthermore, the crane further comprises a boom bracket and a mounting shaft, wherein the upper and lower sides of the right end of the boom are connected to the upper and lower ends of the boom bracket via two mounting shafts. The mounting shaft is used to mount the boom bracket, and the boom bracket facilitates the installation and fixing of the crane boom.

[0013] Compared with the prior art, the beneficial effects of the folding arm crane boom structure are:

[0014] 1. The second boom realizes reciprocating motion through a linear drive mechanism installed on the first boom. A limit device for controlling the stroke of the second boom is installed on the first boom. The front limit block and the rear limit block are fixedly connected to the second boom. The stroke of the hydraulic cylinder is reduced by a very small amount through mechanical limit, avoiding the piston in the hydraulic cylinder pressing against the head or tail of the hydraulic cylinder to cause damage to the hydraulic cylinder, ensuring that the hydraulic cylinder is always in normal operation.

[0015] 2. The limiting solution is simple and reliable, and the thrust or pull required by the hydraulic cylinder does not require a large design redundancy, which helps reduce production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of the utility model;

[0017] Figure 2 For this utility model Figure 1 A schematic diagram of the partially enlarged structure at center A;

[0018] Figure 3 This is a schematic diagram of the internal structure of the boom 1 in the present invention;

[0019] Figure 4 This is a schematic structural diagram of the second boom in the present invention;

[0020] Figure 5 This is a schematic structural diagram of the limiting device in the utility model;

[0021] In the figure: 1 boom bracket, 2 mounting shaft, 3 boom 1, 4 boom 2, 5 reinforcement frame, 6 movable frame, 7 linear drive mechanism, 71 support, 72 movable shaft 1, 73 hydraulic cylinder, 74 movable shaft 2, 8 limit device, 81 screw, 82 limit seat, 83 limit column, 84 horizontal sliding column, 85 buffer spring, 86 buffer slider, 9 through slot, 10 front limit block, 11 rear limit block. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] For example 1, please refer to Figures 1 to 4 The utility model provides a technical solution: a folding arm crane boom structure, including a boom 1 3, a boom 2 4 and a limit device 8. The boom 1 3 and the boom 2 4 are both cylindrical structures with open ends. The boom 1 3 is laterally slidably connected to the boom 2 4, and a limited gap is left between the inner front side of the boom 1 3 and the front side of the boom 2 4. The top of the right end of the boom 1 3 is connected to the top of the left end of the boom 2 4 through a linear drive mechanism 7.

[0024] A limiting device 8 is installed in the middle of the front side of the left end of the boom 1 3, a front limiting block 10 is installed in the middle of the front side of the left end of the boom 2 4 at a position corresponding to the limiting device 8, and a rear limiting block 11 is installed in the middle of the front side of the right end of the boom 2 4 at a position corresponding to the limiting device 8.

[0025] It also includes a boom bracket 1 and a mounting shaft 2. The upper and lower sides of the right end of the boom 3 are respectively connected to the upper and lower ends of the boom bracket 1 through two mounting shafts 2. The mounting shaft 2 is used to install the boom bracket 1, and the boom bracket 1 is convenient for installing and fixing the crane boom.

[0026] It also includes a reinforcement frame 5 and a movable frame 6. The movable frame 6 is installed on the top of the left end of the boom 2 4 through the reinforcement frame 5. The reinforcement frame 5 is used to install the movable frame 6, and the movable frame 6 is used to connect the linear drive mechanism 7.

[0027] The linear drive mechanism 7 includes a hydraulic cylinder 73. The top right end of boom 1 (3) is movably connected to the fixed end of hydraulic cylinder 73, and the telescopic end of hydraulic cylinder 73 is movably connected to the movable frame 6. The extension or contraction of hydraulic cylinder 73 can push boom 2 (4) to move left and right relative to boom 1 (3), thereby changing the length of the crane boom formed by boom 1 (3) and boom 2 (4). The limit device 8, front limit block 10, rear limit block 11, boom 1 (3), and boom 2 (4) cooperate to prevent the piston from pressing against the cylinder head when hydraulic cylinder 73 is extended to its maximum value, or to prevent the piston from pressing against the cylinder tail when hydraulic cylinder 73 is shortened to its minimum value, thereby preventing damage to hydraulic cylinder 73. Since the piston no longer presses against the cylinder head or tail, hydraulic cylinder 73 always operates normally and within its normal operating range. Therefore, the design of hydraulic cylinder 73 no longer requires excessive thrust or tension redundancy.

[0028] The hydraulic cylinder 73 is connected to a hydraulic source via a hydraulic pipeline and a solenoid valve, and the extension and retraction control of the hydraulic cylinder 73 adopts existing technology.

[0029] The linear drive mechanism 7 further includes a support 71, a movable shaft 1 72, and a movable shaft 2 74. The support 71 is fixedly connected to the top of the right end of the boom 1 3. The support 71 is movably connected to the fixed end of the hydraulic cylinder 73 via the movable shaft 1 72. The telescopic end of the hydraulic cylinder 73 is movably connected to the movable frame 6 via the movable shaft 2 74. The support 71 and the movable shaft 1 72 cooperate to allow the fixed end of the hydraulic cylinder 73 to be movably connected to the boom 1 3. The telescopic end of the hydraulic cylinder 73 cooperates with the movable frame 6 to allow the telescopic end of the hydraulic cylinder 73 to be movably connected to the boom 2 4. The movable shaft 1 72 and the movable shaft 2 74 are arranged parallel to each other. Since both ends of the hydraulic cylinder 73 are movably connected to the external structure, even if there is clearance when the boom 1 3 and the boom 2 4 are extended or retracted, the radial force on the hydraulic cylinder 73 is reduced, thereby preventing damage to the hydraulic cylinder 73 due to radial force.

[0030] Limiting device 8 comprises screw 81, limiting seat 82, and limiting post 83. The middle portion of the left front end of boom 1 (3) is fixedly connected to limiting seat 82 via screw 81. Limiting post 83 is mounted in the middle of limiting seat 82. The rear end of limiting post 83 passes through the left front end of boom 1 (3) and extends into the limiting gap. The rear end of limiting post 83 is located between front limiting block 10 and rear limiting block 11. Screw 81 is used to install limiting seat 82, which is used to install limiting post 83. The placement of limiting post 83 prevents the front and rear limiting blocks 10, 11 from being restricted, allowing boom 2 (4) to slide left and right within boom 1 (3) within a certain range.

[0031] The operation of the linear drive mechanism 7 can drive the boom 2 4 to move left and right relative to the boom 1 3, so that the boom 2 4 can be extended or retracted into the boom 1 3, completing the extension and retraction of the crane boom. The boom 2 4 continues to extend from the boom 1 3, and eventually the rear limit block 11 will be limited by the limit device 8, preventing the linear drive mechanism 7 from extending to the limit of the hydraulic cylinder in itself. The boom 2 4 continues to retract into the boom 1 3, and eventually the front limit block 10 will be limited by the limit device 8, preventing the linear drive mechanism 7 from shortening to the limit of the hydraulic cylinder in itself, thereby protecting the linear drive mechanism 7.

[0032] For example 2, please refer to Figures 1 to 5 The present invention provides a technical solution: a folding arm crane boom structure. The structure of this embodiment is roughly the same as that of the first embodiment, except that:

[0033] The limiting device 8 also includes a transverse sliding column 84, a buffer spring 85 and a buffer slider 86. A rectangular mounting groove is provided in the middle of the limiting seat 82, and two transverse sliding columns 84 are fixedly connected in the rectangular mounting groove. The buffer slider 86 is horizontally slidably connected to the middle of the two transverse sliding columns 84, and a buffer spring 85 is respectively sleeved on both ends of each transverse sliding column 84. A through groove 9 is provided on the front side of the left end of the boom 3 at a position corresponding to the rectangular mounting groove. The rear end of the buffer slider 86 is fixedly connected to the front end of the limiting column 83, and the rear end of the limiting column 83 passes through the through groove 9 and extends into the limiting gap. When boom 2 4 moves left and right relative to boom 1 3 to the limit point, the front limit block 10 and the rear limit block 11 will collide with the limit column 83 as boom 2 4 moves, which can easily cause a large impact, causing the crane boom to vibrate and easily damaging the limit column 83. Therefore, a buffer slider 86 is provided. When the buffer slider 86 moves left and right relative to the cross sliding column 84, it will be buffered by the buffer spring 85. Therefore, the limit column 83 will also have a certain left and right buffering range, reducing the collision impact of the front limit block 10 and the rear limit block 11 with the limit column 83, reducing the vibration that may be generated by the crane boom, protecting the crane boom, and reducing the wear of the limit column 83. Although this buffering method can reduce the impact when the front limit block 10 and the rear limit block 11 contact the limit column 83, it will also sacrifice the stroke of the hydraulic cylinder to a certain extent.

[0034] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0035] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A folding arm crane boom structure, comprising boom 1 (3), boom 2 (4) and a limit device (8), wherein the boom 1 (3) and boom 2 (4) are both cylindrical structures with both ends open, and characterized in that: The first arm (3) is connected to the second arm (4) in a transverse sliding manner, and a limited gap is left between the inner front side of the first arm (3) and the front side of the second arm (4), and the top of the right end of the first arm (3) is connected to the top of the left end of the second arm (4) through a linear drive mechanism (7); A limiting device (8) is installed at the middle of the front side of the left end of the boom 1 (3), a front limiting block (10) is installed at the middle of the front side of the left end of the boom 2 (4) at a position corresponding to the limiting device (8), and a rear limiting block (11) is installed at the middle of the front side of the right end of the boom 2 (4) at a position corresponding to the limiting device (8).

2. The boom structure of a folding arm crane according to claim 1, characterized in that: It also includes a reinforcing frame (5) and a movable frame (6), and the movable frame (6) is installed on the top of the left end of the second boom (4) through the reinforcing frame (5).

3. The boom structure of a folding arm crane according to claim 2, characterized in that: The linear drive mechanism (7) includes a hydraulic cylinder (73), the top of the right end of the boom (3) is movably connected to the fixed end of the hydraulic cylinder (73), and the telescopic end of the hydraulic cylinder (73) is movably connected to the movable frame (6).

4. The boom structure of a folding arm crane according to claim 3, characterized in that: The linear drive mechanism (7) further comprises a support (71), a movable shaft 1 (72) and a movable shaft 2 (74); the top right end of the boom 1 (3) is fixedly connected to the support (71); the support (71) is movably connected to the fixed end of the hydraulic cylinder (73) via the movable shaft 1 (72); the telescopic end of the hydraulic cylinder (73) is movably connected to the movable frame (6) via the movable shaft 2 (74).

5. The boom structure of a folding arm crane according to claim 1, characterized in that: The limiting device (8) includes a screw (81), a limiting seat (82) and a limiting column (83), the middle part of the front side of the left end of the boom (3) is fixedly connected to the limiting seat (82) by the screw (81), the middle part of the limiting seat (82) is installed with the limiting column (83), the rear end of the limiting column (83) passes through the front side of the left end of the boom (3) and extends into the limiting gap, and the rear end of the limiting column (83) is located between the front limiting block (10) and the rear limiting block (11).

6. The boom structure of a folding arm crane according to claim 5, characterized in that: The limiting device (8) further comprises a transverse sliding column (84), a buffer spring (85) and a buffer slider (86); a rectangular mounting groove is provided in the middle of the limiting seat (82); two transverse sliding columns (84) are fixedly connected in the rectangular mounting groove; the buffer slider (86) is transversely slidably connected to the middle of the two transverse sliding columns (84); and a buffer spring (85) is respectively sleeved on both ends of each transverse sliding column (84); a through groove (9) is provided on the front side of the left end of the boom (3) at a position corresponding to the rectangular mounting groove; the rear end of the buffer slider (86) is fixedly connected to the front end of the limiting column (83); and the rear end of the limiting column (83) passes through the through groove (9) and extends into the limiting gap.

7. The boom structure of a folding arm crane according to claim 1, characterized in that: It also includes a boom bracket (1) and a mounting shaft (2), wherein the upper and lower sides of the right end of the boom (3) are connected to the upper and lower ends of the boom bracket (1) via two mounting shafts (2) respectively.

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