Hanging basket structure
By installing a forward-moving anti-overturning device and an inverted "U"-shaped clamping structure in the hanging basket structure, the problem of the hanging basket overturning during rapid movement was solved, achieving a more stable and efficient construction process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2026-04-07
AI Technical Summary
Existing hanging basket structures are prone to overturning when moved too quickly, affecting project efficiency.
A forward-moving anti-overturning device is installed in the middle of the sliding track, including an inverted "U"-shaped clamping structure and a hydraulic pushing mechanism. The inverted "U"-shaped clamping structure limits the main truss load-bearing mechanism, and together with the sliding track and anchoring mechanism, it prevents overturning.
It effectively distributes the pressure on the rear hook wheel assembly, extends the service life of the hook wheels, prevents the hanging basket from overturning, and improves project efficiency.
Smart Images
Figure CN224092333U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of bridge pouring structure, especially a hanging basket structure. BACKGROUND
[0002] The hanging basket construction is a construction technology commonly used for bridge cantilever pouring, and is widely applied to bridge engineering of large span, complex structure and special terrain. The main advantages of the hanging basket construction include small environmental impact, high construction precision, strong applicability and the like, and the construction can be carried out without disturbing the surrounding environment and traffic.
[0003] The hanging basket construction is usually composed of a bearing structure, a suspension system, a running system and an anchoring system, and can be adjusted and moved according to engineering needs. In the construction process, the hanging basket carries out concrete pouring, prestressed tension and other operations on the poured beam section to complete the construction of the bridge section.
[0004] The design principles of the hanging basket include light self weight, simple structure, firmness and stability, easy forward movement and assembly and disassembly, and strong reusability. Although the structure of the existing hanging basket is relatively mature, the anchoring mechanism is lacking at the rear end of the main truss bearing mechanism in the moving process, so that instability may occur. Therefore, the main truss bearing mechanism needs to be moved slowly, otherwise the problem of overturning may occur. However, slow movement will affect the engineering efficiency, and therefore the existing structure needs to be improved. UTILITY MODEL CONTENT
[0005] The utility model aims to provide a hanging basket structure, which solves the problem that the existing hanging basket structure is prone to overturning when moving too fast.
[0006] To solve the above technical problems, the utility model adopts the following technical scheme:
[0007] A hanging basket structure, comprising a main truss bearing mechanism, a suspension mechanism, an anchoring mechanism, a running mechanism and a formwork mechanism, the running mechanism is arranged on the top surface of the poured beam section, the bottom surface of the main truss bearing mechanism is connected with the sliding rail of the running mechanism, the middle part of the sliding rail of the running mechanism is detachably provided with a forward movement anti-overturning device, the bottom surface of the forward movement anti-overturning device is in contact with the top surface of the bottom rod of the main truss bearing mechanism after installation, the top of the suspension mechanism is connected with the main truss bearing mechanism, the bottom of the suspension mechanism is connected with the support structure of the formwork mechanism, the anchoring mechanism comprises a main truss anchoring mechanism and a formwork anchoring mechanism, the main truss anchoring mechanism is arranged at the rear end of the main truss bearing mechanism and connected with the box girder reserved hole, the formwork anchoring mechanism is arranged at the front end of the poured beam section and connected with the support structure of the formwork mechanism through the poured beam section, and the formwork mechanism comprises a side formwork, an outer formwork and an inner formwork mechanism.
[0008] A forward-moving anti-tipping device is installed in the middle of the sliding track. This effectively distributes the pressure on the hook wheels of the rear hook wheel assembly, which not only effectively extends the service life of the hook wheels in the rear hook wheel assembly, but also effectively prevents the hanging basket from tipping over due to excessively fast movement, thus improving engineering efficiency.
[0009] As a further preferred embodiment of this utility model, the traveling mechanism includes a sliding track pad, a sliding track, a rear hook wheel assembly, and a hydraulic push mechanism. The sliding track pad is laid at the bottom of the sliding track, and the sliding tracks are arranged in parallel. Each sliding track consists of at least two sections, and the misalignment of the sliding track joints is less than 3mm. The rear hook wheel assembly is located at the rear of the sliding track, and the top surface of the hook wheel of the rear hook wheel assembly contacts the bottom surface of the upper flange of the sliding track. The hydraulic push mechanism is located at the front of the sliding track, and the front end of the output shaft of the hydraulic push mechanism is connected to the track sliding connection structure located at the front end of the bottom of the main truss load-bearing mechanism.
[0010] Each sliding track consists of at least two sections, which makes it easier to assemble and disassemble, and to move quickly and easily. When the main truss load-bearing mechanism needs to be moved, it can be moved smoothly and simply by using the hydraulic push mechanism output shaft.
[0011] As a further preferred embodiment of this invention, the density of the sliding track pads arranged at the front of the sliding track is greater than the density of the sliding track pads arranged in the middle and rear of the sliding track.
[0012] As a further preferred embodiment of this utility model, the forward anti-overturning device includes an inverted "U"-shaped clamping structure. The clamping width of the inverted "U"-shaped clamping structure is adapted to the width of the bottom rod of the main truss load-bearing mechanism and the width of the sliding track of the traveling mechanism. The lower end of the inverted "U"-shaped clamping structure is detachably connected to the sliding track pad of the traveling mechanism. The top surface and both sides of the clamping position of the "U"-shaped clamping structure are provided with ball bearings.
[0013] When relocation is required, first install the inverted "U" shaped clamping structure, and then remove the main truss anchoring mechanism. In this process, the inverted "U" shaped clamping structure can limit the bottom rod of the main truss load-bearing mechanism, thereby preventing the main truss load-bearing mechanism from overturning. The ball bearings set on the top surface and both sides of the clamping position of the "U" shaped clamping structure can make the main truss load-bearing mechanism move more smoothly.
[0014] As a further preferred embodiment of this utility model, the main truss load-bearing mechanism includes a rhomboid main truss, a cross brace, and a front upper crossbeam. The rhomboid main truss is connected by the cross brace, and the front upper crossbeam is disposed on the top surface of the front end of the rhomboid main truss.
[0015] As a further preferred embodiment of this utility model, the suspension mechanism includes a side mold suspension mechanism, a bottom mold suspension mechanism, and an inner mold suspension mechanism. The upper ends of the side mold suspension mechanism and the inner mold suspension mechanism are both connected to the front upper crossbeam, and the lower ends of the side mold suspension mechanism and the inner mold suspension mechanism are respectively connected to the front end of the side mold sliding beam and the front end of the inner mold sliding beam. The bottom mold suspension mechanism includes a bottom basket rear lower crossbeam suspension mechanism and a bottom basket front lower crossbeam suspension mechanism. The top of the bottom basket rear lower crossbeam suspension mechanism and the top of the bottom basket front lower crossbeam suspension mechanism are respectively connected to the crossbeam and the front upper crossbeam, and the bottom of the bottom basket rear lower crossbeam suspension mechanism and the bottom basket front lower crossbeam suspension mechanism are respectively connected to the bottom bottom mold rear lower crossbeam and the bottom bottom mold front lower crossbeam.
[0016] As a further preferred embodiment of this utility model, the template anchoring mechanism includes a side template anchoring mechanism, an outer template anchoring mechanism, and an inner template anchoring mechanism. The side template anchoring mechanism includes a side template anchoring structure and a side template sliding beam load-bearing hanger. The side template anchoring structure passes downward through the cast-in-place beam segment and connects to the side template sliding beam load-bearing hanger below the cast-in-place beam segment. The outer template anchoring mechanism is located in the middle of the front end of the cast-in-place beam segment. The outer template anchoring mechanism passes downward through the cast-in-place beam segment and connects to the bottom basket of the bottom formwork below the cast-in-place beam segment. The inner template anchoring mechanism includes an inner template anchoring structure and an inner template sliding beam load-bearing hanger. The inner template anchoring structure passes downward through the cast-in-place beam segment and connects to the inner template sliding beam load-bearing hanger below the cast-in-place beam segment.
[0017] As a further preferred embodiment of the present invention, the anchoring mechanism further includes a sliding track anchoring mechanism disposed in the middle of the sliding track of the traveling mechanism.
[0018] The distance between the two anchoring points of the sliding track anchoring mechanism shall not exceed 1.5 meters.
[0019] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:
[0020] 1. A forward-moving anti-tipping device is installed in the middle of the sliding track. This can effectively share the pressure borne by the hook wheels of the rear hook wheel group, which can not only effectively extend the service life of the hook wheels in the rear hook wheel group, but also effectively prevent the overturning problem caused by the rapid movement of the hanging basket, thus improving the efficiency of the project.
[0021] 2. Each sliding track consists of at least two sections, which makes it easier to assemble and disassemble, and to move quickly and easily. When the main truss load-bearing mechanism needs to be moved, it can be moved smoothly and simply by using the hydraulic push mechanism output shaft.
[0022] 3. When relocation is required, first install the inverted "U" shaped clamping structure, and then remove the main truss anchoring mechanism. In this process, the inverted "U" shaped clamping structure can limit the bottom rod of the main truss load-bearing mechanism, thereby preventing the main truss load-bearing mechanism from overturning. The ball bearings set on the top surface and both sides of the clamping position of the "U" shaped clamping structure can make the main truss load-bearing mechanism move more smoothly.
[0023] 4. The distance between the two anchoring points of the sliding track anchoring mechanism shall not exceed 1.5 meters. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the structure of this utility model.
[0025] Figure 2 This is a schematic diagram of the walking mechanism of this utility model.
[0026] Figure 3 This is a structural schematic diagram of the main truss load-bearing mechanism of this utility model.
[0027] Figure 4 This is a schematic diagram of the layout of the suspension mechanism of this utility model.
[0028] Figure 5 This is a schematic diagram of the layout of the template anchoring mechanism of this utility model.
[0029] Figure 6 This is a schematic diagram of the inverted "U" shaped clamping structure of this utility model. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can typically be arranged and designed in various different configurations.
[0031] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0032] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.
[0033] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0034] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0035] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Specific Implementation
[0036] Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 A hanging basket structure is shown, including a main truss load-bearing mechanism 1, a suspension mechanism 2, an anchoring mechanism 3, a traveling mechanism 4, and a formwork mechanism. The traveling mechanism 4 is located on the top surface of the cast-in-place beam segment. The bottom surface of the main truss load-bearing mechanism 1 is connected to the sliding track 42 of the traveling mechanism 4. A forward anti-overturning device 5 is detachably provided in the middle of the sliding track 42 of the traveling mechanism 4. After the forward anti-overturning device 5 is installed, its bottom surface contacts the top surface of the bottom rod of the main truss load-bearing mechanism 1. The top of the suspension mechanism 2 is connected to the main truss load-bearing mechanism 1, and the bottom of the suspension mechanism 2 is connected to the support structure of the formwork mechanism. The anchoring mechanism 3 includes a main truss anchoring mechanism 31 and a formwork anchoring mechanism 32. The main truss anchoring mechanism 31 is located at the rear end of the main truss load-bearing mechanism 1 and is connected to the reserved hole of the box girder. The formwork anchoring mechanism 32 is located at the front end of the cast-in-place beam segment and passes downward through the cast-in-place beam segment to connect with the support structure of the formwork mechanism. The formwork mechanism includes side formwork, outer formwork, and inner formwork.
[0037] A forward-moving anti-tipping device is installed in the middle of the sliding track. This effectively distributes the pressure on the hook wheels of the rear hook wheel assembly, which not only effectively extends the service life of the hook wheels in the rear hook wheel assembly, but also effectively prevents the hanging basket from tipping over due to excessively fast movement, thus improving engineering efficiency. Specific Implementation
[0038] This embodiment further describes the traveling mechanism 4 based on specific embodiment 1. The traveling mechanism 4 includes a sliding track pad 41, a sliding track 42, a rear hook wheel assembly 43, and a hydraulic push mechanism 44. The sliding track pad 41 is laid on the bottom of the sliding track 42. The sliding tracks 42 are arranged in parallel, and each sliding track 42 consists of at least two sections. The misalignment of the joints of the sliding tracks 42 is less than 3mm. The rear hook wheel assembly 43 is located at the rear of the sliding track 42, and the top surface of the hook wheel of the rear hook wheel assembly 43 contacts the bottom surface of the upper flange of the sliding track 42. The hydraulic push mechanism 44 is located at the front of the sliding track 42, and the front end of the output shaft of the hydraulic push mechanism 44 is connected to the track sliding connection structure 6 located at the front end of the bottom of the main truss load-bearing mechanism 1.
[0039] Each sliding track consists of at least two sections, which makes it easier to assemble and disassemble, and to move quickly and easily. When the main truss load-bearing mechanism needs to be moved, it can be moved smoothly and simply by using the hydraulic push mechanism output shaft. Specific Implementation
[0040] This embodiment further describes the sliding track 42 based on specific embodiment 2. The density of the sliding track pads 41 arranged at the front of the sliding track 42 is greater than the density of the sliding track pads 41 arranged in the middle and rear of the sliding track 42. Specific Implementation
[0041] This embodiment further describes the forward-moving anti-overturning device 5 based on specific embodiment 1. The forward-moving anti-overturning device 5 includes an inverted "U"-shaped clamping structure. The clamping width of the inverted "U"-shaped clamping structure is adapted to the width of the bottom rod of the main truss load-bearing mechanism 1 and the width of the sliding track 42 of the traveling mechanism. The lower end of the inverted "U"-shaped clamping structure is detachably connected to the sliding track pad 41 of the traveling mechanism 4. The top surface and both sides of the clamping position of the "U"-shaped clamping structure are provided with ball bearings 7.
[0042] When relocation is required, first install the inverted "U" shaped clamping structure, and then remove the main truss anchoring mechanism. In this process, the inverted "U" shaped clamping structure can limit the bottom rod of the main truss load-bearing mechanism, thereby preventing the main truss load-bearing mechanism from overturning. The ball bearings set on the top surface and both sides of the clamping position of the "U" shaped clamping structure can make the main truss load-bearing mechanism move more smoothly. Specific Implementation
[0043] This embodiment further describes the main truss load-bearing mechanism 1 based on specific embodiment 1. The main truss load-bearing mechanism 1 includes a rhomboid main truss 11, a cross brace 12, and a front upper cross beam 13. The rhomboid main truss 11 is connected by the cross brace 12, and the front upper cross beam 13 is located on the top surface of the front end of the rhomboid main truss 11. Specific Implementation
[0044] This embodiment further describes the suspension mechanism 2 based on specific embodiment 1. The suspension mechanism 2 includes a side mold suspension mechanism 21, a bottom mold suspension mechanism 22, and an inner mold suspension mechanism 23. The upper ends of the side mold suspension mechanism 21 and the inner mold suspension mechanism 23 are connected to the front upper crossbeam 13, and the lower ends of the side mold suspension mechanism 21 and the inner mold suspension mechanism 23 are respectively connected to the front end of the side mold sliding beam 8 and the front end of the inner mold sliding beam 9. The bottom mold suspension mechanism 23... The lifting mechanism 22 includes a rear lower crossbeam suspension mechanism 221 and a front lower crossbeam suspension mechanism 222. The top of the rear lower crossbeam suspension mechanism 221 and the top of the front lower crossbeam suspension mechanism 222 are respectively connected to the cross link 12 and the front upper crossbeam 13. The bottom of the rear lower crossbeam suspension mechanism 221 and the bottom of the front lower crossbeam suspension mechanism 222 are respectively connected to the rear lower crossbeam and the front lower crossbeam of the bottom mold. Specific Implementation
[0045] This embodiment further describes the template anchoring mechanism 32 based on specific embodiment 6. The template anchoring mechanism 32 includes a side template anchoring mechanism 321, an outer template anchoring mechanism 322, and an inner template anchoring mechanism 323. The side template anchoring mechanism 321 includes a side template anchoring structure and a side formwork sliding beam load-bearing hanger. The side template anchoring structure passes downward through the cast-in-place beam segment and is connected to the side formwork sliding beam load-bearing hanger below the cast-in-place beam segment. The outer template anchoring mechanism 322 is located in the middle of the front end of the cast-in-place beam segment. The outer template anchoring mechanism 322 passes downward through the cast-in-place beam segment and is connected to the bottom basket and lower crossbeam at the bottom of the bottom formwork below the cast-in-place beam segment. The inner template anchoring mechanism 323 includes an inner template anchoring structure and an inner formwork sliding beam load-bearing hanger. The inner template anchoring structure passes downward through the cast-in-place beam segment and is connected to the inner formwork sliding beam load-bearing hanger below the cast-in-place beam segment. Specific Implementation
[0046] This embodiment further describes the anchoring mechanism 3 based on specific embodiment 1. The anchoring mechanism 3 also includes a sliding track anchoring mechanism 34 disposed in the middle of the sliding track 42 of the traveling mechanism 4.
[0047] The distance between the two anchoring points of the sliding track anchoring mechanism shall not exceed 1.5 meters.
[0048] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A hanging basket structure, comprising a main truss load-bearing mechanism (1), a suspension mechanism (2), an anchoring mechanism (3), a traveling mechanism (4), and a template mechanism, characterized in that: The traveling mechanism (4) is set on the top surface of the cast beam section. The bottom surface of the main truss bearing mechanism (1) is connected to the sliding rail (42) of the traveling mechanism (4). The sliding rail (42) of the traveling mechanism (4) is detachably equipped with a forward anti-overturning device (5) in the middle. After the forward anti-overturning device (5) is installed, its bottom surface contacts the top surface of the bottom rod of the main truss bearing mechanism (1). The top of the suspension mechanism (2) is connected to the main truss bearing mechanism (1). The bottom is connected to the support structure of the template mechanism. The anchoring mechanism (3) includes the main truss anchoring mechanism (31) and the template anchoring mechanism (32). The main truss anchoring mechanism (31) is located at the rear end of the main truss load-bearing mechanism (1) and connected to the reserved hole of the box girder. The template anchoring mechanism (32) is located at the front end of the cast beam segment. The template anchoring mechanism (32) passes downward through the cast beam segment and is connected to the support structure of the template mechanism. The template mechanism includes side templates, outer templates and inner template mechanisms.
2. The hanging basket structure according to claim 1, characterized in that: The traveling mechanism (4) includes a sliding track pad (41), a sliding track (42), a rear hook wheel assembly (43), and a hydraulic push mechanism (44). The sliding track pad (41) is laid on the bottom of the sliding track (42). The sliding tracks (42) are arranged in parallel. Each sliding track (42) consists of at least two sections. The misalignment of the joints of the sliding tracks (42) is less than 3 mm. The rear hook wheel assembly (43) is located at the rear of the sliding track (42). The top surface of the hook wheel of the rear hook wheel assembly (43) is in contact with the bottom surface of the upper flange of the sliding track (42). The hydraulic push mechanism (44) is located at the front of the sliding track (42). The front end of the output shaft of the hydraulic push mechanism (44) is connected to the track sliding connection structure (6) located at the front end of the bottom of the main truss load-bearing mechanism (1).
3. The hanging basket structure according to claim 2, characterized in that: The density of the sliding track pads (41) arranged at the front of the sliding track (42) is greater than that of the sliding track pads (41) arranged in the middle and rear of the sliding track (42).
4. The hanging basket structure according to claim 1, characterized in that: The forward anti-overturning device (5) includes an inverted "U" shaped clamping structure. The clamping width of the inverted "U" shaped clamping structure is adapted to the width of the bottom rod of the main truss load-bearing mechanism (1) and the width of the sliding track (42) of the traveling mechanism. The lower end of the inverted "U" shaped clamping structure is detachably connected to the sliding track pad (41) of the traveling mechanism (4). The top surface and both sides of the clamping position of the "U" shaped clamping structure are provided with ball bearings (7).
5. The hanging basket structure according to claim 1, characterized in that: The main truss load-bearing mechanism (1) includes a rhomboid main truss (11), a cross brace (12) and a front upper cross beam (13). The rhomboid main truss (11) is connected by the cross brace (12), and the front upper cross beam (13) is located on the top surface of the front end of the rhomboid main truss (11).
6. The hanging basket structure according to claim 1, characterized in that: The suspension mechanism (2) includes a side mold suspension mechanism (21), a bottom mold suspension mechanism (22), and an inner mold suspension mechanism (23). The upper ends of the side mold suspension mechanism (21) and the inner mold suspension mechanism (23) are connected to the front upper crossbeam (13), and the lower ends of the side mold suspension mechanism (21) and the inner mold suspension mechanism (23) are connected to the front end of the side mold sliding beam (8) and the front end of the inner mold sliding beam (9), respectively. The bottom mold suspension mechanism (22) includes a bottom basket and a rear lower crossbeam. The beam suspension mechanism (221) and the bottom basket front lower crossbeam suspension mechanism (222) are respectively connected to the cross link (12) and the front upper crossbeam (13) at the top of the bottom basket rear lower crossbeam suspension mechanism (221) and the bottom basket front lower crossbeam suspension mechanism (222). The bottom of the bottom basket rear lower crossbeam suspension mechanism (221) and the bottom of the bottom basket front lower crossbeam suspension mechanism (222) are respectively connected to the bottom basket rear lower crossbeam and the bottom basket front lower crossbeam at the bottom of the bottom mold.
7. The hanging basket structure according to claim 6, characterized in that: The template anchoring mechanism (32) includes a side template anchoring mechanism (321), an outer template anchoring mechanism (322), and an inner template anchoring mechanism (323). The side template anchoring mechanism (321) includes a side template anchoring structure and a side template sliding beam load-bearing hanger. The side template anchoring structure passes downward through the cast beam segment and is connected to the side template sliding beam load-bearing hanger below the cast beam segment. The outer template anchoring mechanism (322) is located in the middle of the front end of the cast beam segment. The outer template anchoring mechanism (322) passes downward through the cast beam segment and is connected to the bottom basket of the bottom formwork below the cast beam segment. The inner template anchoring mechanism (323) includes an inner template anchoring structure and an inner template sliding beam load-bearing hanger. The inner template anchoring structure passes downward through the cast beam segment and is connected to the inner template sliding beam load-bearing hanger below the cast beam segment.
8. The hanging basket structure according to claim 1, characterized in that: The anchoring mechanism (3) also includes a sliding track anchoring mechanism (34) located in the middle of the sliding track (42) of the traveling mechanism (4).