CN220283387U - Balance mechanism of bridge crane grab bucket and grab bucket - Google Patents

Abstract

The utility model relates to the technical field of bridge cranes, and discloses a balance mechanism and a grab bucket of a bridge crane, wherein the grab bucket of the bridge crane comprises a balance mechanism and a main structure, the balance mechanism is arranged at the top of the main structure, the balance mechanism is connected with a pair of first steel wire ropes for lifting the traction grab bucket, the main structure is connected with a pair of second steel wire ropes for opening and closing the traction grab bucket, the balance mechanism comprises a balance frame body, two pairs of wear-resistant sleeves capable of rotating by taking a central axis of the balance frame body as a rotating shaft are arranged in the balance frame body, and a steel wire rope channel is formed between each pair of wear-resistant sleeves; one end of the pair of first steel wire ropes is connected with a driving source, and the other ends of the pair of first steel wire ropes are respectively and fixedly connected with the balance frame body; one end of the pair of second steel wire ropes is connected with a driving source, and the other end of the pair of second steel wire ropes respectively penetrates through one steel wire rope channel and is connected with the main body structure. The utility model can keep balance of the grab bucket during operation and also takes the service life of the steel wire rope into consideration.

Description

Balance mechanism of bridge crane grab bucket and grab bucket

Technical Field

The utility model relates to the technical field of bridge cranes, in particular to a balance mechanism of a grab bucket of a bridge crane and the grab bucket.

Background

The bridge crane mainly comprises a crane bridge device (a cart), a trolley, a grab bucket, a crane running mechanism and electric components, wherein a lifting and opening and closing control mechanism of the grab bucket is arranged on the trolley, and the grab bucket is connected with a winding drum of the lifting and opening and closing mechanism by four steel wires to respectively control lifting and opening of the grab bucket.

Because can form unilateral angle of piling up in the material storehouse when producing, the inclination of its major structure can be great when the grab bucket snatchs the material in-process at the grab bucket, and the uneven phenomenon of atress appears easily to two wire ropes that are responsible for going up and down is obvious, for this reason, the present grab bucket is commonly configured with a balance mechanism, and balance mechanism connects at grab bucket major structure's top, and direct and two wire ropes that are responsible for going up and down link to each other, and balance mechanism's setting can make the major structure of grab bucket keep balance when the operation. However, the arrangement of the balance mechanism easily affects two steel wire ropes responsible for opening and closing the grab bucket, and the two steel wire ropes responsible for opening and closing the grab bucket need to penetrate through the balance mechanism to be connected to the corresponding winding drum, so that when the inclination angle of the main body structure of the grab bucket is large, the two steel wire ropes responsible for opening and closing the grab bucket are in direct contact with the balance mechanism during operation, the main body frame of the balance mechanism is generally a sharper section bar, the two steel wire ropes can be accelerated and worn under the action of sliding friction force, the service life of the steel wire ropes is influenced, the maintenance workload is greatly increased, and the very adverse effect is brought to the stable operation of production.

Disclosure of Invention

The utility model aims to provide a balance mechanism of a grab bucket of a bridge crane and the grab bucket. The utility model can keep the balance of the main body structure of the grab bucket during operation, and simultaneously gives consideration to the service life of the steel wire rope, thereby effectively reducing the workload of later maintenance.

The technical scheme of the utility model is as follows: the utility model provides a balance mechanism of a grab bucket of a bridge crane, which comprises a balance mechanism and a main body structure, wherein the balance mechanism is arranged at the top of the main body structure, the balance mechanism is connected with a pair of first steel wire ropes for pulling the grab bucket to lift, the main body structure is connected with a pair of second steel wire ropes for pulling the grab bucket to open and close, the balance mechanism comprises a balance frame body, two pairs of wear-resistant sleeves capable of rotating by taking a central axis of the balance frame body as a rotating shaft are arranged in the balance frame body, and a steel wire rope channel is formed between each pair of wear-resistant sleeves; one end of the pair of first steel wire ropes is connected with a driving source, and the other ends of the pair of first steel wire ropes are respectively and fixedly connected with the balance frame body; one end of the pair of second steel wire ropes is connected with a driving source, and the other ends of the pair of second steel wire ropes respectively penetrate through one steel wire rope channel and are connected with the main body structure.

Compared with the prior art, the balance mechanism has the beneficial effects that: the balance mechanism is connected to the top of the grab main body structure, and a pair of first steel wire ropes for pulling the grab to lift are connected to the balance mechanism, so that the grab main body structure can be balanced during operation, and the grab can be stably operated; meanwhile, two pairs of wear-resistant sleeves capable of rotating by taking the central axis of the wear-resistant sleeves as a rotating shaft are arranged in the balance frame body of the balance mechanism, a second steel wire rope used for pulling the grab to open and close passes through a steel wire rope channel between the pair of wear-resistant sleeves, when the inclination angle of a main body structure of the grab is large in the operation process, the second steel wire rope can be contacted with one of the pair of wear-resistant sleeves due to the inclination of the main body structure, the wear-resistant sleeves play a role of supporting the second steel wire rope, and due to the smooth and round surface of the wear-resistant sleeves, excessive abrasion and cutting of the second steel wire rope cannot be caused, when the second steel wire rope is wound, the wear-resistant sleeves contacted with the second steel wire rope are driven to rotate, at the moment, the friction force between the second steel wire rope and the wear-resistant sleeves is rolling friction force, and compared with the conventional steel wire rope subjected to sliding friction force, the wear speed of the steel wire rope is slower, and the service life of the steel wire rope is prolonged. In addition, after the utility model is applied to the grab bucket, whether the second steel wire rope is excessively worn or not does not need to be frequently detected, so that the workload of later maintenance is effectively reduced, and the working efficiency and the working safety are improved.

In the balancing mechanism of the bridge crane grab bucket, the balancing frame body is in a cuboid shape formed by encircling a pair of long side plates and a pair of short side plates, two pairs of partition plates are connected between opposite inner side walls of the long side plates, and a pair of wear-resistant sleeves are connected between opposite side walls of each pair of partition plates.

In the balancing mechanism of the bridge crane grab bucket, the top ends of the wear-resistant sleeves are flush with the top ends of the balancing frame body.

In the balance mechanism of the bridge crane grab bucket, four partition plates are parallel to the short side plates, the wear-resistant sleeve comprises a fixed shaft, a plurality of pairs of U-shaped grooves which extend along the vertical direction and are upwards opened are formed in the opposite side walls of each pair of partition plates, and two ends of the fixed shaft are embedded into one pair of U-shaped grooves for installation.

In the balance mechanism of the bridge crane grab bucket, the side wall of the partition plate where the U-shaped groove is located is detachably connected with a limit bolt, and the limit bolt is used for penetrating through the partition plate and the end part of the limit bolt is located above the fixed shaft so as to limit the fixed shaft in the vertical direction.

In the balance mechanism of the bridge crane grab bucket, the wear-resistant sleeve further comprises a rubber sleeve sleeved outside the fixed shaft, and anti-slip lines are arranged on the outer surface of the rubber sleeve.

In the balancing mechanism of the bridge crane grab bucket, a fixed pin shaft is connected between the short side plate and the partition plate closest to the short side plate, and one end, connected with the balancing frame body, of the first steel wire rope is specifically and fixedly connected to the fixed pin shaft.

In the balance mechanism of the bridge crane grab bucket, the fixed pin shaft is provided with a plurality of annular concave parts formed by cutting along the circumferential direction in the length direction, and one end of the first steel wire rope connected with the fixed pin shaft is specifically and fixedly connected with one of the annular concave parts.

In the balancing mechanism of the bridge crane grab bucket, a hanging plate is connected between the two middle partition plates, and the lower end of the hanging plate extends to the outer side of the lower end of the balancing frame body.

In a second aspect, the utility model provides a grab bucket comprising a balancing mechanism as described in the first aspect, further comprising a connecting plate and a main body structure for grabbing materials, wherein the balancing mechanism is connected to the upper end of the connecting plate, and the main body structure is connected to the lower end of the connecting plate.

Since the technical improvements and the technical effects of the grab bucket provided by the second aspect of the utility model are the same as those of the balance mechanism provided by the first aspect, the technical effects of the grab bucket will not be repeated.

Drawings

FIG. 1 is a top view of the balance mechanism of the present utility model;

FIG. 2 is a side view of the counterbalance mechanism of the present utility model;

FIG. 3 is a front view of the balancing mechanism of the present utility model;

FIG. 4 is a schematic view of the mounting structure of the wear sleeve between a pair of bulkheads;

FIG. 5 is a cross-sectional view of the internal structure of the wear sleeve;

FIG. 6 is a schematic illustration of the mating structure of the end of the wear sleeve with the U-shaped groove;

fig. 7 is a schematic view of the mounting structure of the fixing pin between the short side plate and the partition plate.

Reference numerals: 1-first steel wire rope, 2-second steel wire rope, 3-balance frame body, 4-abrasion-proof sleeve, 5-steel wire rope channel, 31-long side plate, 32-short side plate, 33-baffle, 34-fixed pin shaft, 35-hanging plate, 41-fixed shaft, 42-rubber sleeve, 331-U-shaped groove, 332-limit bolt, 341-annular concave part and 421-anti-skid grain.

Detailed Description

The utility model is further illustrated by the following figures and examples, which are not intended to be limiting.

The embodiment of the utility model provides a balance mechanism of a grab bucket of a bridge crane, the structure is shown in figures 1 to 3, the grab bucket of the bridge crane comprises a balance mechanism and a main structure, the balance mechanism is arranged at the top of the main structure, the balance mechanism is connected with a pair of first steel wire ropes 1 for lifting the traction grab bucket, the main structure is connected with a pair of second steel wire ropes 2 for opening and closing the traction grab bucket, the balance mechanism comprises a balance frame body 3, two pairs of wear-resistant sleeves 4 capable of rotating by taking a central axis of the balance frame body 3 as a rotating shaft are arranged in the balance frame body, and a steel wire rope channel 5 is formed between each pair of wear-resistant sleeves 4; one end of the pair of first steel wire ropes 1 is connected with a driving source, and the other ends of the pair of first steel wire ropes are respectively and fixedly connected with the balance frame body 3; one end of the pair of second wire ropes 2 is connected with a driving source, and the other end passes through one wire rope channel 5 respectively and is connected with the main body structure.

In this embodiment, the structure of the balancing mechanism is mainly described, and the balancing mechanism is specifically applied to the grab bucket of the bridge crane and can be regarded as a small component on the grab bucket, so that the cart, the crane operating mechanism, the electrical component and the main structure of the grab bucket of the bridge crane in this embodiment can refer to a conventional bridge crane; the main structure of the grab bucket is a part of the grab bucket, and the grab bucket without the balance mechanism can be regarded as the grab bucket.

In general, the driving sources connected with the first steel wire rope 1 and the second steel wire rope 2 are all winding motors fixed on the bridge crane trolley, and under the action of the respective winding motors, a pair of first steel wire ropes 1 synchronously complete winding and unwinding, and correspond to the lifting of the grab bucket; the pair of second steel wire ropes 2 synchronously complete the retraction and the release, and correspond to the opening and the closing of the grab bucket.

In the embodiment, the balance mechanism is connected to the top of the grab main body structure, and the pair of first steel wire ropes 1 for pulling the grab to lift are connected to the balance mechanism, so that the grab main body structure can be balanced during operation, and the grab can be stably operated; meanwhile, two pairs of wear-resistant sleeves 4 capable of rotating by taking the central axis of the wear-resistant sleeves as a rotating shaft are arranged in the balance frame body 3 of the balance mechanism, the second steel wire ropes 2 used for pulling the grab to open and close penetrate through the steel wire rope channels 5 between the pair of wear-resistant sleeves 4, when the inclination angle of the main body structure of the grab is large in the operation process, the second steel wire ropes 2 can be contacted with one of the pair of wear-resistant sleeves 4 due to the inclination of the main body structure, the wear-resistant sleeves 4 play a role of supporting the second steel wire ropes 2, and due to the smooth and round surface of the wear-resistant sleeves 4, excessive abrasion and cutting of the second steel wire ropes 2 cannot be caused, when the second steel wire ropes 2 are wound, the wear-resistant sleeves 4 contacted with the second steel wire ropes 2 are driven to rotate, and at the moment, the friction force between the second steel wire ropes 2 and the wear-resistant sleeves 4 is rolling friction force, and compared with the conventional steel wire ropes subjected to sliding friction force, the wear speed of the steel wire ropes is slower, and the service life of the steel wire ropes is prolonged. In addition, after the balance mechanism is applied to the grab bucket, whether the second steel wire rope 2 is excessively worn or not does not need to be frequently detected, so that the work load of later maintenance is effectively reduced, and the work efficiency and the work safety are improved.

Alternatively, referring to fig. 1, the balance frame 3 is in a rectangular parallelepiped shape surrounded by a pair of long side plates 31 and a pair of short side plates 32, two pairs of partition plates 33 are connected between opposite inner side walls of the pair of long side plates 31, and a pair of wear-resistant sleeves 4 are connected between opposite side walls of each pair of partition plates 33.

In this embodiment, the balance frame 3 includes a plurality of plate structures of a long side plate 31, a short side plate 32 and a partition 33, and the balance frame 3 can be manufactured by welding the plates, so that the structure is simple and easy to manufacture, and the reliability is good; the arrangement of the two pairs of partition plates 33 separates the inside of the balance frame body 3 into a plurality of independent spaces, after the pair of wear-resistant sleeves 4 are connected between the pair of partition plates 33, a wire rope channel 5 with four closed sides in the horizontal direction and two open ends in the vertical direction is formed in the inside of the balance frame body 3, so that the path of the second wire rope 2 passing through the balance frame body 3 is uniquely determined, and the pair of second wire ropes 2 respectively pass through one wire rope channel 5 without excessive interference.

Alternatively, referring to fig. 3, the top ends of the wear sleeves 4 are each flush with the top end of the balance frame 3.

In this embodiment, when the inclination of the main body structure of the grab bucket is larger during operation, the second steel wire rope 2 contacts with one of the pair of wear-resistant sleeves 4 due to the inclination of the main body structure, and when the height of the top ends of the wear-resistant sleeves 4 and the balance frame body 3 is set to be flush, the main body structure can be inclined, the second steel wire rope 2 can contact with the wear-resistant sleeves 4 at the first time, and the second steel wire rope 2 is prevented from being worn and split due to contact with other sections of the balance frame body 3.

Alternatively, referring to fig. 1, 4 and 6, four partitions 33 are disposed parallel to the short side plates 32, and the wear sleeve 4 includes a fixed shaft 41, and a plurality of pairs of U-shaped grooves 331 extending in a vertical direction and opening upward are provided on opposite side walls of each pair of partitions 33, and both ends of the fixed shaft 41 are fitted into one of the pairs of U-shaped grooves 331.

In this embodiment, a plurality of pairs of U-shaped grooves 331 are formed in opposite side walls of the partition 33 along the vertical direction, the U-shaped grooves 331 are designed to facilitate the installation of the wear-resistant sleeves 4, only two pairs of two wear-resistant sleeves 4 need to be selected for installation in the plurality of pairs of U-shaped grooves 331, and the distance between the two wear-resistant sleeves 4 can be adjusted by the design of the plurality of pairs of U-shaped grooves 331, so that the wear-resistant sleeves can be selected according to practical situations.

It should be noted that, the U-shaped groove 331 adopts a structure with a wide upper part and a narrow lower part, so that the installation of the wear-resistant sleeve 4 is facilitated, an arc surface is designed at the bottom of the U-shaped groove 331 in the vertical direction, and the arc surface is attached to the outer cylindrical surface of the fixed shaft 41, so that the position of the wear-resistant sleeve 4 after installation is unique, and the stability after installation is good.

Alternatively, referring to fig. 4 and 6, a limit bolt 332 is detachably connected to the sidewall of the partition 33 where the U-shaped groove 331 is located, the limit bolt 332 is used to penetrate through the partition 33 and the end of the limit bolt 332 is located above the fixed shaft 41, after the end of the fixed shaft 41 of the wear-resistant sleeve 4 is embedded into the U-shaped groove 331 for installation, the limit bolt 332 is installed, so that after the limit bolt 332 is installed in place, the end of the limit bolt extends above the fixed shaft 41, and the limit on the fixed shaft 41 in the vertical direction is performed.

In this embodiment, after the wear-resistant sleeve 4 is mounted on the U-shaped groove 331, in order to limit the wear-resistant sleeve 4 in the vertical direction, the utility model designs a limit bolt 332 which can be detached from the side wall of the partition 33, the mounting height of the limit bolt 332 is specifically set according to the diameter of the fixed shaft 41, and assuming that the diameter of the fixed shaft 41 is a, the distance between the lower end of the threaded hole of the corresponding limit bolt 332 on the side wall of the partition 33 and the bottom of the U-shaped groove 331 in the vertical direction is slightly greater than a, specifically 1.1a-1.3a, so that after the wear-resistant sleeve 4 is mounted on the U-shaped groove 331, the limit bolt 332 can be inserted into the threaded hole to limit the wear-resistant sleeve 4, and when the limit bolt 332 is inserted, the allowance of the up-and-down movement of the fixed shaft 41 is kept between 0.1a-0.3a, the allowance is left out without obstructing the rotation of the wear-resistant sleeve 4, and the up-down jumping amplitude of the wear-resistant sleeve 4 can be reduced.

Optionally, referring to fig. 4 and 5, the wear-resistant sleeve 4 further includes a rubber sleeve 42 sleeved outside the fixed shaft 41, and an outer surface of the rubber sleeve 42 is provided with anti-slip lines 421.

In this embodiment, the design of the rubber sleeve 42 and the anti-slip lines 421 on the surface thereof can effectively avoid the slipping phenomenon when the second steel wire rope 2 is wound, thereby improving the stability of the second steel wire rope 2 when wound; in addition, the rubber sleeve 42 can be detached from the fixed shaft 41 for replacement, and as the service time increases, the second steel wire rope 2 and the wear-resistant sleeve 4 can generate certain wear, and for the wear-resistant sleeve 4, when the wear is worn to a certain degree, only the rubber sleeve 42 needs to be replaced, so that the maintenance cost is low.

Alternatively, referring to fig. 1 and 7, a fixed pin 34 is connected between the short side plate 32 and the nearest partition 33, and one end of the first wire rope 1 connected to the balance frame 3 is specifically and fixedly connected to the fixed pin 34.

In this embodiment, the fixing pin 34 is used as a connection force point of the first steel wire ropes 1 on the balancing mechanism, and the fixing pin 34 is disposed between the short side plate 32 and the closest partition plate 33, that is, the distance between the pair of first steel wire ropes 1 is larger than the distance between the pair of second steel wire ropes 2, so as to help to promote the stability of hoisting the grab bucket.

Alternatively, referring to fig. 7, the fixed pin 34 is provided with a plurality of annular recesses 341 cut in the circumferential direction in the length direction, and one end of the first wire rope 1 connected to the fixed pin 34 is fixedly connected to one of the annular recesses 341.

In the present embodiment, the annular concave portion 341 is used for connection of the end portion of the first wire rope 1, and can effectively prevent the first wire rope 1 from slipping in the axial direction thereof after being connected to the fixing pin 34; in addition, the design of the plurality of annular concave portions 341 enables the distance between the pair of first steel wires 1 to be adaptively adjusted according to working conditions so as to adapt to different working environments.

Alternatively, referring to fig. 1 and 3, a hanger plate 35 is connected between the two partition plates 33 located in the middle, and the lower end of the hanger plate 35 extends to the outside of the lower end of the balance frame 3.

In this embodiment, the hanging plate 35 is perpendicular to the two partition plates 33, and is connected by adopting a welded connection mode, so that the overall structural strength of the balance frame body 3 can be improved, and the part of the hanging plate extending to the outer side of the lower end of the balance frame body 3 can be connected with the main body structure of the grab bucket, thereby having the effect of dual purposes.

In addition, the utility model also provides a grab bucket, which comprises the balance mechanism of the embodiment, a connecting plate and a main body structure for grabbing materials, wherein the balance mechanism is connected to the upper end of the connecting plate, and the main body structure is connected to the lower end of the connecting plate.

In this embodiment, the connecting plate is also called an orifice plate, and is essentially a planar plate structure with upper and lower holes, and the hole at the upper end of the connecting plate is used for connecting with the hanger plate 35 of the balancing mechanism, specifically, is fixedly connected by matching of bolts and nuts; the hole of connecting plate lower extreme is used for being connected with the major structure.

Because the technical improvement and the obtained technical effect of the grab bucket provided by the utility model are the same as those of the grab bucket provided by the balance mechanism, the technical effect of the grab bucket is not repeated.

In the description of the present utility model, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present utility model and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

The above is only a preferred embodiment of the present utility model, and the protection scope of the present utility model is not limited to the above examples, and all technical solutions belonging to the concept of the present utility model belong to the protection scope of the present utility model. It should be noted that modifications and adaptations to the present utility model may occur to one skilled in the art without departing from the principles of the present utility model and are intended to be within the scope of the present utility model.

Claims (10)

1. The balance mechanism of the grab bucket of the bridge crane comprises a balance mechanism and a main structure, wherein the balance mechanism is arranged at the top of the main structure, the balance mechanism is connected with a pair of first steel wire ropes (1) for pulling the grab bucket to lift, and the main structure is connected with a pair of second steel wire ropes (2) for pulling the grab bucket to open and close, and the balance mechanism is characterized by comprising a balance frame body (3), two pairs of wear-resistant sleeves (4) capable of rotating by taking a central axis of the balance frame body (3) as a rotating shaft are arranged in the balance frame body, and a steel wire rope channel (5) is formed between each pair of wear-resistant sleeves (4); one end of the pair of first steel wire ropes (1) is connected with a driving source, and the other ends of the pair of first steel wire ropes are fixedly connected with the balance frame bodies (3) respectively; one end of the pair of second steel wire ropes (2) is connected with a driving source, and the other end of the pair of second steel wire ropes passes through one steel wire rope channel (5) respectively and is connected with the main body structure.

2. The balance mechanism of a bridge crane grab according to claim 1, wherein the balance frame body (3) is in a rectangular parallelepiped shape surrounded by a pair of long side plates (31) and a pair of short side plates (32), two pairs of partition plates (33) are connected between opposite inner side walls of the pair of long side plates (31), and a pair of wear-resistant sleeves (4) are connected between opposite side walls of each pair of partition plates (33).

3. Balance mechanism for bridge crane grab according to claim 2, characterized in that the top ends of the wear sleeves (4) are all level with the top ends of the balance frame body (3).

4. Balance mechanism of bridge crane grab according to claim 2, characterized in that four of said partition plates (33) are arranged parallel to said short side plates (32), said wear-resistant sleeve (4) comprises a fixed shaft (41), a plurality of pairs of U-shaped grooves (331) extending in vertical direction and opening upward are provided on opposite side walls of each pair of said partition plates (33), and both ends of said fixed shaft (41) are fitted into one of said pairs of U-shaped grooves (331).

5. The balance mechanism of a bridge crane grab according to claim 4, wherein a limit bolt (332) is detachably connected to the side wall of the partition plate (33) where the U-shaped groove (331) is located, and the limit bolt (332) is used for penetrating through the partition plate (33) and the end of the limit bolt is located above the fixed shaft (41) so as to limit the fixed shaft (41) in the vertical direction.

6. The balance mechanism of a bridge crane grab according to claim 4, wherein the wear-resistant sleeve (4) further comprises a rubber sleeve (42) sleeved outside the fixed shaft (41), and an outer surface of the rubber sleeve (42) is provided with anti-slip grains (421).

7. The balance mechanism of a bridge crane grab according to any of claims 2-6, characterized in that a fixed pin (34) is connected between the short side plate (32) and the nearest partition plate (33), and one end of the first steel wire rope (1) connected with the balance frame body (3) is specifically and fixedly connected to the fixed pin (34).

8. The bridge crane grab balancing mechanism according to claim 7, wherein the fixed pin shaft (34) is provided with a plurality of annular concave parts (341) formed by cutting along the circumferential direction in the length direction, and one end of the first steel wire rope (1) connected with the fixed pin shaft (34) is specifically and fixedly connected at one of the annular concave parts (341).

9. Balance mechanism for a bridge crane grab according to any of claims 2-6, characterized in that a hanger plate (35) is connected between the two intermediate partition plates (33), the lower end of the hanger plate (35) extending outside the lower end of the balance frame body (3).

10. A grab bucket, comprising a balancing mechanism according to any one of claims 1-9, further comprising a connecting plate and a body structure for grabbing material, the balancing mechanism being connected to the upper end of the connecting plate, the body structure being connected to the lower end of the connecting plate.