Scissor fork frame structure and lifting equipment

Abstract

The utility model discloses a scissor frame structure and lifting equipment, and belongs to the field of scissor frames. According to the technical scheme, the shear fork frame structure comprises a plurality of inner fork beams and a plurality of outer fork beams, center hinge points are arranged in the middles of the inner fork beams and the outer fork beams, center reinforcing plates are fixedly installed at the center hinge points and are rhombic, and the long axes of the center reinforcing plates and the length directions of the inner fork beams or the outer fork beams form included angles; end hinge points are arranged at the two ends of the inner fork beam and the two ends of the outer fork beam respectively, end reinforcing plates are fixedly installed at the end hinge points, each end reinforcing plate comprises a hinge part and an extending part, and the extending parts extend towards the end points of the center reinforcing plate and are gradually narrowed in the extending direction. According to the shear fork frame structure, the reinforcing plates are arranged at the hinged points of the beam bodies, so that local strength is improved; the reinforcing plates are designed to be of a narrow and long structure and are arranged in a wave shape in the stress transmission direction, stress is reduced, stress concentration is reduced, and the structural strength of the shear fork frame after light weight is guaranteed.

Description

Technical Field

[0001] The utility model relates to the field of scissor frames, in particular to a scissor frame structure and a lifting device. Background Art

[0002] Scissor lift equipment is a kind of lifting device widely used in the fields of industry, logistics, construction, etc. The equipment mainly includes the base or body part at the bottom, the scissor frame and its drive device, and the working platform at the top of the scissor frame. Its basic principle is to realize the vertical movement of the lifting platform through the cross-arranged scissor support structure. This design is not only compact and stable, but also has a wide lifting range, which can meet the lifting needs in different scenarios.

[0003] The load during the lifting and lowering process of the scissor frame is a dynamic load, and the force changes with the lifting height, so the fork frame is prone to fatigue damage. In addition to being affected by the cylinder hinge point, the force and force transmission of the fork frame are also related to the stiffness coordination between the various welded structural parts of the fork frame. With the needs of lightweighting and cost reduction, many improvements have been made to the structure of the lifting equipment, including lightweighting of the frame base and lightweighting of the scissor frame. Among them, the lightweighting of the scissor frame is achieved on the one hand by improving the material purchase and selecting lighter materials, and on the other hand by thinning the beam of the scissor frame.

[0004] However, for a fork frame with reasonable stiffness coordination between the welded structural parts, when the wall thickness of the rectangular tube is thinned, the bending interface coefficient of the rectangular tube decreases, the local stiffness of the rectangular tube decreases, and the stress will be concentrated to the position with weaker stiffness during the transmission process. The weaker the stiffness, the more concentrated the stress, the greater the stress value, and the more likely it is to have weld cracking, rectangular tube tearing and other phenomena that seriously affect safety. Utility Model Content

[0005] Aiming at the problem that the scissor frame beam body is easily damaged due to stress concentration after being thinned, the utility model provides a scissor frame structure with a local reinforcement structure.

[0006] In order to solve the above-mentioned problems, the technical solution adopted by the utility model is: a scissor frame structure, including multiple inner fork beams and multiple outer fork beams, a central hinge point is provided in the middle of the inner fork beams and the outer fork beams, a central reinforcing plate is fixedly installed at the central hinge point, the central reinforcing plate is rhombus-shaped, the central hinge point is located at the center of the rhombus, the long axis of the central reinforcing plate is arranged at an angle with the length direction of the inner fork beam or the outer fork beam, the central reinforcing plate located on the inner fork beam and the central reinforcing plate located on the outer fork beam are arranged in an "X" shape and staggered; end hinge points are respectively provided at both ends of the inner fork beam and the outer fork beam, end reinforcing plates are fixedly installed at the end hinge points, the end reinforcing plates include a hinge part and an extension part, the end hinge point is located at the center of the hinge part, the extension part extends toward the end point of the central reinforcing plate and gradually narrows along the extension direction; the end reinforcing plate located on the inner fork beam and the end reinforcing plate located on the outer fork beam are mirror-symmetrical in the vertical plane. The scissor frame structure of this scheme is provided with a reinforcing plate at the hinge point of the beam body to improve the local strength; the reinforcing plate is designed to be a narrow and long structure, and is arranged in a wave shape along the stress transfer direction, which reduces stress and stress concentration, and ensures the structural strength of the scissor frame after lightweighting.

[0007] Preferably, the outer fork beam and the inner fork beam are hinged to each other through a central hinge point, the outer fork beam is located inside the inner fork beam, and the central reinforcement plate and the end reinforcement plates are welded and installed on the opposite surfaces between the outer fork beam and the inner fork beam. The reinforcement plate is located at the connection of the inner and outer fork beams, close to the connection position of the hinge axis, to improve the shear resistance and achieve better strengthening effect.

[0008] Preferably, the ends of the extensions of the end reinforcement plates and both ends of the long axis of the central reinforcement plate are rounded to reduce stress concentration.

[0009] Preferably, the extension portion includes a first side and a second side, the first side is a straight side and extends smoothly along the outer contour of the hinge portion, the second side includes a concave section and a straight section, the concave section is bent in the direction close to the first side, one end of the straight section is connected to the concave section, and the other end of the straight section and the end point of the first side together form the end point of the extension portion; the first side of the extension portion faces the central hinge point. Extending the side of the reinforcing plate facing the direction of stress transmission into an inclined surface and narrowing the width of the side where stress is transmitted can effectively improve the stress situation and reduce stress concentration at the reinforcing plate.

[0010] Preferably, the inner fork beam and the outer fork beam are rectangular tubes, and the vertical side walls of the rectangular tubes are provided with mounting holes penetrating along the hinge axis direction at the center hinge point and the end hinge point, and a round tube hinge seat is installed in the mounting hole, one end of the round tube hinge seat protrudes from the outer surface of the inner fork beam and the inner surface of the outer fork beam, and the center reinforcement plate is provided with a circular hole at the position corresponding to the center hinge point and the end reinforcement plate is provided with a circular hole, and the protruding end of the round tube hinge seat is located in the circular hole. The rectangular tube wall and the reinforcement plate jointly support the round tube hinge seat, and the wall thickness is locally increased to improve the strength of the hinge position.

[0011] On the other hand, the utility model also provides a lifting device, which adopts the above-mentioned scissor frame structure.

[0012] Through the above technical scheme, it can be seen that the beneficial effect of the utility model is that the scissor frame structure adopts the form of a plate to locally reinforce the installation position of the hinge shaft, and the shape of the reinforcement plate is optimized. The middle part adopts a long rhombus and the two ends adopt a teardrop shape. The layout of the reinforcement plate is along the stress transfer direction. The overall direction of the reinforcement plate on the same beam body is "wave" shaped, which can effectively reduce the stress. At the same time, the end reinforcement plate extends the side of the reinforcement plate facing the direction of stress transmission into an inclined plane, and narrows the width of the side where the stress is transmitted, which can effectively improve the stress condition and reduce the stress concentration at the reinforcement plate; the scissor frame structure adopts a through-type circular tube type hinge seat, and at the same time, the wall thickness of the installation place is increased by the reinforcement plate to achieve local reinforcement, which effectively improves the overall strength; based on this, the scheme provides a top lifting device, which ensures the load-bearing performance and safety performance while being lightweight. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solution of the utility model, the drawings required for use in the description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 This is a schematic structural diagram of the first embodiment of the present utility model.

[0015] Figure 2 It is a schematic structural diagram of the inner fork beam in the first embodiment of the utility model.

[0016] Figure 3 It is a schematic structural diagram of the first end reinforcement plate in the first embodiment of the utility model.

[0017] Figure 4 It is a schematic structural diagram of the outer fork beam in the first embodiment of the utility model.

[0018] Description of main reference numerals

[0019] 1. Inner fork beam, 2. Outer fork beam, 3. Round tube hinge seat, 4. Hinge shaft, 5-1. First center reinforcement plate, 5-2. Second center reinforcement plate, 6-1. First end reinforcement plate, 6-2. Second end reinforcement plate, 6-11. Hinge portion, 6-12. Extension portion, 6-13. First side edge, 6-14. Second side edge. DETAILED DESCRIPTION

[0020] In order to make the purpose, features and advantages of the utility model more obvious and easy to understand, the technical scheme of the utility model will be clearly and completely described below in combination with the drawings in the specific embodiment. Obviously, the embodiments described below are only part of the embodiments of the utility model, not all of them. Based on the embodiments in this patent, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this patent.

[0021] Embodiment 1

[0022] like Figure 1 As shown, the scissor frame structure includes a plurality of inner fork beams 1 and outer fork beams 2. In this embodiment, the inner fork beams 1 and the outer fork beams 2 are divided into two groups to form two scissor mechanisms. The two scissor mechanisms are connected in parallel to form an integral scissor frame structure. In this way, the inner fork beams 1 are the beam bodies relatively close to the inside of the whole, and the outer fork beams 2 are the beam bodies relatively close to the outside of the whole, that is, the outer fork beams 2 are installed on the opposite side of the inner fork beams 1. That is, in Figure 1 In the direction shown in , each beam extending from the upper left to the lower right is an outer fork beam 2, and the structure of each outer fork beam 2 is basically the same; the beam extending from the lower left to the upper right is an inner fork beam 1, and the structure of each inner fork beam 1 is basically the same, the difference is that some inner fork beams are provided with a connecting structure of a lifting device (this is a common structure of the scissors frame and will not be repeated here).

[0023] The scissors-fork mechanism is divided into multiple scissors-fork units, and one scissors-fork unit includes an inner fork beam and an outer fork beam: on the inner fork beam 1, a first central hinge point is provided in the middle of the inner fork beam 1, and first end hinge points are provided at both ends; on the outer fork beam 2, a second central hinge point is provided in the middle of the outer fork beam 2, and second end hinge points are provided at both ends, the first central hinge point is hinged to the second central hinge point, so that the scissors-fork units form an "X" shape structure, and the first end hinge point is hinged to the second central hinge point of the outer fork beam 2 in the adjacent scissors-fork unit, so as to connect multiple scissors-fork units in series (the first and second end hinge points at the uppermost end are connected to the working platform, and the first and second end hinge points at the lowermost end are connected to the equipment base).

[0024] like Figure 2As shown, on the inner fork beam 1, a first central reinforcing plate 5-1 and a first end reinforcing plate 6-1 are provided on the side facing the outer fork beam 2. The first central reinforcing plate 5-1 is a diamond-shaped structure with rounded corners. The first central reinforcing plate 5-1 is welded and installed at the first central hinge point, and the first central hinge point is located at the center of the first central reinforcing plate 5-1. The long axis (long diagonal) of the first central reinforcing plate 5-1 forms a certain angle with the length direction of the inner fork beam 1, and the long axis of the first central reinforcing plate is closer to the horizontal relative to the inner fork beam 1, that is, Figure 2 In the embodiment, the first central reinforcement plate 5-1 is in a nearly horizontal state, while the inner fork beam 1 is more inclined relative to the horizontal direction. Figure 3 The first end reinforcement plate 6-1 is welded and fixed at the first end hinge point. The first end reinforcement plate 6-1 includes a hinge portion 6-11 and an extension portion 6-12. The center of the hinge portion 6-11 coincides with the first end hinge point. The extension portion is located on one side of the outer periphery of the hinge portion 6-11 and extends toward the middle of the inner fork beam 1, and the end thereof points to the long axis vertex of the first center reinforcement plate 5-1 to which it is close, that is, at Figure 2 In the figure, the extension of the first end reinforcement plate located at the lower left points to the left vertex of the first central reinforcement plate 5-1, and the extension of the first end reinforcement plate located at the upper right points to the right vertex of the first central reinforcement plate 5-1. Specifically, the extension is an approximately triangular structure, which can be understood as one side of which is connected to the hinge portion, and the other two sides are defined as the first side 6-13 and the second side 6-14, respectively. The first side 6-13 is a straight side and extends smoothly along the outer contour of the hinge portion, that is, Figure 3 In the illustrated embodiment, the outer contour of the hinge portion is an arc shape, the first side extends through a tangent of the arc, turns through a rounded corner in the middle, and then extends again along a straight line for a certain length, the second side 6-14 includes a concave section and a straight section, one end of the concave section is connected to the outer contour of the hinge portion, and the concave section and the outer contour of the hinge portion transition smoothly, the other end of the concave section is connected to one end of the straight section and transitions smoothly, the other end of the smooth section extends in a straight line direction and converges with the first side 6-13 to form the end point of the extension portion, and then, the end reinforcement plate has a "9"-shaped contour. At the same time, it can be seen that on the inner fork beam, the two end reinforcement plates form a central symmetry with the central hinge point as the center, and the directions of the two extensions and the long axis direction of the center reinforcement plate between the two constitute a wavy line relative to the length direction of the inner fork beam.

[0025] like Figure 4As shown, on the outer fork beam 2, the side facing the inner fork beam 1 is provided with a second center reinforcement plate 5-2 and a second end reinforcement plate 6-2. The second center reinforcement plate 5-2 has the same structure as the first center reinforcement plate 5-1. In terms of installation, the center of the second center reinforcement plate 5-2 is located at the second center hinge point. The long axis (long diagonal) of the second center reinforcement plate 5-2 forms a certain angle with the length direction of the outer fork beam 2, and the long axis of the second center reinforcement plate is closer to the horizontal relative to the outer fork beam 2. It can be understood that the second center reinforcement plate 5-2 has the same rotation angle as the first center reinforcement plate 5-1 relative to the horizontal direction, and the clockwise direction is opposite. In this way, the long axes of the second center reinforcement plate 5-2 and the first center reinforcement plate 5-1 form an "X"-shaped intersection. The structure of the second end reinforcement plate 6-2 is a mirror-symmetrical structure of the first end reinforcement plate 6-1. In terms of installation, the layout of the second center reinforcement plate 5-2 is also mirror-symmetrical to the layout of the first end reinforcement plate 6-1 and the first center reinforcement plate 5-1.

[0026] The inner fork beam 1 and the outer fork beam 2 are rectangular tubes, and the central hinge point and the end hinge point on the vertical side wall of the rectangular tube are provided with mounting holes penetrating along the hinge axis direction, and a round tube hinge seat 3 is installed in the mounting hole, and one end of the round tube hinge seat 3 protrudes from the outer surface of the inner fork beam 1 and the inner surface of the outer fork beam 2, and a circular hole is provided at the position corresponding to the central hinge point on the central reinforcement plate (including the first central reinforcement plate 5-1 and the second central reinforcement plate 5-2, the two have the same structure) and at the position corresponding to the end hinge point on the end reinforcement plate (including the first end reinforcement plate 6-1 and the second end reinforcement plate 6-2, the two have mirror-symmetric structures), and the protruding end of the round tube hinge seat 3 is located in the circular hole. During assembly, the first central hinge point and the second central hinge point are coaxially arranged, the first end hinge point is coaxially arranged with the adjacent second end hinge point, and the hinge shaft 4 is installed in the corresponding circular tube hinge seat.

[0027] Embodiment 2

[0028] Based on the scissor frame structure provided in the first embodiment, this embodiment further provides a lifting device, which adopts the scissor frame structure described in the first embodiment.

[0029] It can be seen from the above implementation modes that the beneficial effect of the utility model is that the scissor frame structure adopts the form of a plate to locally reinforce the installation position of the hinge shaft, and the shape of the reinforcement plate is optimized, with a long rhombus in the middle and a teardrop shape at both ends. The reinforcement plate is arranged along the stress transfer direction, and the overall direction of the reinforcement plate on the same beam is "wave" shaped, which can effectively reduce the stress. At the same time, the end reinforcement plate extends the side of the reinforcement plate facing the direction of stress transmission into an inclined plane, and narrows the width of the side where the stress is transmitted, which can effectively improve the stress condition and reduce the stress concentration at the reinforcement plate; the scissor frame structure adopts a through-type circular tube-type hinged seat, and at the same time, the wall thickness of the installation place is increased by the reinforcement plate to achieve local reinforcement, which effectively improves the overall strength; based on this, the present scheme provides a top lifting device, which ensures the load-bearing performance and safety performance while being lightweight.

[0030] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A scissor frame structure, comprising a plurality of inner fork beams (1) and a plurality of outer fork beams (2), It is characterized in that A central hinge point is provided in the middle of the inner fork beam (1) and the outer fork beam (2), and a central reinforcement plate is fixedly installed at the central hinge point. The central reinforcement plate is rhombus-shaped, and the central hinge point is located at the center of the rhombus. The long axis of the central reinforcement plate is arranged at an angle with the length direction of the inner fork beam (1) or the outer fork beam (2). The central reinforcement plate located on the inner fork beam (1) and the central reinforcement plate located on the outer fork beam (2) are arranged in an "X" shape and staggered. The inner fork beam (1) and the outer fork beam (2) are respectively provided with end hinge points at both ends, and end reinforcement plates are fixedly installed at the end hinge points. The end reinforcement plates include a hinge portion and an extension portion. The end hinge point is located at the center of the hinge portion. The extension portion extends toward the end point of the center reinforcement plate and gradually narrows along the extension direction. The end reinforcement plate located on the inner fork beam (1) and the end reinforcement plate located on the outer fork beam (2) are mirror-symmetrical in a vertical plane.

2. The scissor frame structure according to claim 1, It is characterized in that The outer fork beam (2) and the inner fork beam (1) are hinged to each other via a central hinge point; the outer fork beam (2) is located on the inner side of the inner fork beam (1); and the central reinforcement plate and the end reinforcement plates are welded and installed on the opposite surfaces between the outer fork beam (2) and the inner fork beam (1).

3. The scissor frame structure according to claim 1, It is characterized in that The ends of the extension parts of the end reinforcement plates and both ends of the long axis of the central reinforcement plate are rounded.

4. The scissor frame structure according to claim 1, It is characterized in that The extension portion includes a first side and a second side, the first side is a straight side and extends smoothly along the outer contour of the hinge portion, the second side includes a concave section and a straight section, the concave section is bent in a direction close to the first side, one end of the straight section is connected to the concave section, and the other end of the straight section and the endpoint of the first side together form an endpoint of the extension portion; the first side of the extension portion faces the central hinge point.

5. The scissor frame structure according to any one of claims 1 to 4, It is characterized in that The inner fork beam (1) and the outer fork beam (2) are rectangular tubes, and mounting holes penetrating along the hinge axis direction are provided at the central hinge point and the end hinge point on the vertical side wall of the rectangular tube, and a round tube hinge seat (3) is installed in the mounting hole, and one end of the round tube hinge seat (3) protrudes from the outer surface of the inner fork beam (1) and the inner surface of the outer fork beam (2), and circular holes are provided at the position corresponding to the central hinge point on the central reinforcement plate and the position corresponding to the end hinge point on the end reinforcement plate, and the protruding end of the round tube hinge seat (3) is located in the circular hole.

6. A lifting device, It is characterized in that A scissor frame structure as described in any one of claims 1 to 5 is adopted.

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