CN110790126A

CN110790126A - Lifting appliance and lifting mechanism

Info

Publication number: CN110790126A
Application number: CN201911086503.4A
Authority: CN
Inventors: 张�浩; 黄兴博; 张韬懿; 李小宝; 范卫明; 张文军; 胡晓辉
Original assignee: Beijing Xuanyu Intelligent Technology Co Ltd
Current assignee: Beijing Xuanyu Intelligent Technology Co Ltd
Priority date: 2019-11-08
Filing date: 2019-11-08
Publication date: 2020-02-14

Abstract

The application relates to the technical field of hoisting and discloses a lifting appliance. This hoist includes: a first spreader assembly including a first end connected to the lifting mechanism and a second end; a second spreader assembly including a third end rotatably connected to the second end, and a fourth end removably connected to the pendant. The lifting appliance has the advantages that controllability of the lifting process is stronger, the posture adjusting mode of the lifted object is more flexible, and the environmental adaptability of the lifting appliance is stronger. The application also discloses a lifting mechanism containing the lifting appliance.

Description

Lifting appliance and lifting mechanism

Technical Field

The application relates to the technical field of hoisting, for example to hoist and elevating system.

Background

At present, people mainly depend on tools such as steel wire ropes, hoisting belts and the like to hoist, transport and install workpieces or products. Due to inherent characteristics of flexible parts such as a steel wire rope, a hoisting belt and the like, the stability and the accuracy of a hoisting process are insufficient, and particularly, when the operation such as the rotation, the overturning and the like of a hoisted object is carried out, the operation is often accompanied by larger technical risks, and safety accidents such as casualties and the like are easily caused.

In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art:

in the conventional hoisting process, the flexibility of controlling the posture of the hoisted object is not enough.

Disclosure of Invention

The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview nor is intended to identify key/critical elements or to delineate the scope of such embodiments but rather as a prelude to the more detailed description that is presented later.

The embodiment of the disclosure provides a lifting appliance, which aims to solve the technical problem that the flexibility of the posture control of a lifted object is not enough in the conventional lifting process.

In some embodiments, a spreader comprises: a first spreader assembly including a first end connected to the lifting mechanism and a second end; a second spreader assembly including a third end rotatably connected to the second end, and a fourth end removably connected to the pendant.

In some embodiments, a lifting mechanism comprises a spreader as described above.

The lifting appliance and the lifting mechanism provided by the embodiment of the disclosure can realize the following technical effects:

the controllability of the hoisting process is stronger, the posture adjustment mode of the workpiece is more flexible, and the environmental adaptability of the hanger is stronger.

The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the accompanying drawings and not in limitation thereof, in which elements having the same reference numeral designations are shown as like elements and not in limitation thereof, and wherein:

fig. 1 is a schematic view of a spreader according to one embodiment of the present application;

fig. 2 is an exploded view of a first spreader assembly according to one embodiment of the present application;

fig. 3 is an exploded view of a first spreader assembly according to one embodiment of the present application;

fig. 4 is a schematic illustration of a second spreader assembly according to an embodiment of the present application;

fig. 5 is an exploded view of a second spreader assembly according to an embodiment of the present application;

fig. 6 is an exploded view of a second spreader assembly according to an embodiment of the present application;

FIG. 7 is a schematic view of a connection structure of a driving motor and a rotating shaft according to an embodiment of the present application;

fig. 8 is a schematic view of a spreader according to an embodiment of the present application;

FIG. 9 is an enlarged view of portion A of FIG. 1;

FIG. 10 is a schematic illustration of a connection arrangement of a first spreader assembly, a second spreader assembly and a slewing device according to an embodiment of the present application;

FIG. 11 is a schematic structural view of a first spreader assembly according to one embodiment of the present application;

FIG. 12 is a schematic structural view of a first spreader assembly according to one embodiment of the present application;

FIG. 13 is a schematic view of a connection of a spreader to a lifting mechanism according to one embodiment of the present application;

fig. 14 is a schematic view of a connection structure of a spreader and a lifting mechanism according to an embodiment of the present application.

Description of reference numerals:

1. a spreader; 11. a first spreader assembly; 111. a first spreader body; 1111. a through hole; 1112. a first end; 1113. a first lifting lug; 1114. a first interlayer; 1115. a second end; 1116. an accommodating chamber; 12. A second spreader assembly; 121. a second hanger main body; 1211. a third end; 1212. a fourth end; 1213. A second lifting lug; 1214. a second interlayer; 122. a stepped shaft; 1221. a first shaft body; 1222. a second shaft body; 13. rotating the hole; 14. a pin shaft; 15. a bearing; 16. a bearing seat; 17. a rotating shaft; 171. A chute; 2. a lifting mechanism; 21. a grasping section; 3. hanging the object; 31. mounting a lifting lug; 32. installing an interlayer; 4. a drive device; 41. a drive motor; 411. an output shaft of the drive motor; 412. a clamping hole; 42. a sprocket; 43. a chain; 5. a turning device; 51. a rotary motor; 511. an output shaft of the rotary motor; 52. a first gear; 53. a second gear; 531. and (7) fixing holes.

Detailed Description

So that the manner in which the features and elements of the disclosed embodiments can be understood in detail, a more particular description of the disclosed embodiments, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may be practiced without these details. In other instances, well-known structures and devices may be shown in simplified form in order to simplify the drawing.

In the description herein, it is to be understood that the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be construed as limiting the invention. In the description herein, unless otherwise specified and limited, it is to be noted that the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, mechanically or electrically connected, or interconnected between two elements, directly or indirectly through an intermediate medium, and the specific meanings of the terms as described above will be understood by those skilled in the art according to the specific situation.

A spreader is provided, fig. 1 is a schematic illustration of a spreader according to an embodiment of the present application; fig. 2 is an exploded view of a first spreader assembly according to one embodiment of the present application; fig. 3 is an exploded view of a first spreader assembly according to one embodiment of the present application; fig. 4 is a schematic illustration of a second spreader assembly according to an embodiment of the present application; fig. 5 is an exploded view of a second spreader assembly according to an embodiment of the present application; fig. 6 is a schematic illustration of an exploded construction of a second spreader assembly according to one embodiment of the present application.

Referring to fig. 1 to 6, a spreader according to an embodiment of the present disclosure is described, where the spreader 1 includes: a first spreader assembly 11 including a first end 1112 connected to the lifting mechanism 2 and a second end 1115; the second spreader assembly 12 includes a third end 1211 pivotally connected to the second end 1115 and a fourth end 1212 removably connected to the pendant 3.

Alternatively, the work piece, product, and any items that need to be lifted can be considered as hoists.

In this embodiment, when the suspended object needs to be adjusted in the air, the operator only needs to control the second spreader assembly to rotate relative to the first spreader assembly and the second spreader assembly to rotate the suspended object, so as to complete the adjustment of the attitude of the suspended object. The lifting appliance has the advantages that the controllability of the lifting process is stronger, the posture adjusting mode of the lifted object is more flexible, and the environmental adaptability of the lifting appliance is stronger.

In some embodiments, as shown in connection with fig. 1-3, the first end 1112 of the first spreader assembly 11 includes a fixed portion connected to the lifting mechanism 2; the second end 1115 of the first spreader assembly is provided with a bearing 15.

Optionally, the first spreader assembly 11 includes a first spreader body 111, the first spreader body 111 is in the shape of a circular ring, and a through hole 1111 is configured on the first spreader body 111, and the through hole 1111 can be regarded as an inner hole of the circular ring. The first end 1112 of the first spreader main body 111 is integrally formed with two first lifting lugs 1113, and the first lifting lug 1113 may be in the shape of an isosceles triangle. The two first lifting lugs 1113 are symmetrically arranged on two sides of the axis of the first hanger main body 111. The two first lifting lugs 1113 are respectively provided with a rotating hole 13, and the two first lifting lugs 1113 are connected by a pin 14 passing through the rotating holes 13 of the two first lifting lugs 1113. A first interlayer 1114 for installing and fixing the lifting mechanism 2 is formed between the two first lifting lugs 1113. The structure formed by the two first lifting lugs 1113 and the pin 14 can be regarded as a fixing part of the first spreader component 11. The second end 1115 of the first spreader body 111 is disposed opposite the first end 1112. The bearing 15 is provided coaxially with the first hanger body 111. The bearing 15 is first abutted against the end face of the second end 1115 of the first spreader body 111 and then the bearing block 16 is snapped onto the bearing 15 and the bearing block 16 is screwed onto the second end 1115 of the first spreader body 111.

In this embodiment, two isosceles triangle first lifting lugs are provided at one end of the first spreader assembly. The isosceles triangle shape of the first lifting lug ensures good stress of the first lifting tool assembly, and the two first lifting lugs are connected through the pin shaft, so that the lifting mechanism is more stable when lifting a lifted object.

In some embodiments, as shown in connection with fig. 1, 4-6, the second spreader assembly 12 includes: a second hanger body 121 having a third end 1211 connected to the bearing 15; the driving device 4 is disposed at the fourth end 1212 of the second spreader body 121.

Optionally, the second spreader body 121 is cylindrical in shape. The third end 1211 of the second hanger body 121 is provided with a stepped shaft 122, and the stepped shaft 122 may be a two-stage stepped shaft. The first shaft 1221 is arranged at the end with the larger diameter of the stepped shaft 122, and the second shaft 1222 is arranged at the end with the smaller diameter; the first shaft 1221 is welded to the third end 1211. The second shaft body 1222 passes through the hole of the bearing seat 16, the hole of the bearing 15 on the first spreader body 111 and into the through hole 1111 of the first spreader body 111. The first shaft 1221 is fixedly connected to the inner ring of the bearing 15, and the first shaft 1221 may be directly welded to the inner ring of the bearing 15. The second spreader body 121 is fixed to the bearing blocks 16 with screws. The fourth end 1212 and the third end 1211 of the second spreader main body 121 are disposed opposite to each other. Two second lifting lugs 1213 are integrally formed on the fourth end 1212 of the second spreader main body 121, and the second lifting lugs 1213 may have an isosceles triangle shape. The two second lifting lugs 1213 are symmetrically disposed on both sides of the axis of the second hanger body 121. The two second lifting lugs 1213 are respectively provided with a rotation hole 13, and the two second lifting lugs 1213 are connected by a rotation shaft 17 passing through the rotation holes 13 of the two second lifting lugs 1213. A second interlayer 1214 is formed between the two second lifting lugs 1213. The driving device 4 is provided at the second lug 1213.

Alternatively, the second hanger body 121 may rotate with respect to the first hanger body 111 on a horizontal plane in which the end surface of the third end 1211 is located, or may rotate on any horizontal plane parallel to the end surface of the third end 1211.

In this embodiment, the rotatable connection in first hoist main part of second hoist main part can ensure to hang the thing and can carry out the rotation at 360 no dead angles in the horizontal plane, has improved the flexibility ratio of hoist.

FIG. 7 is a schematic view of a connection structure of a driving motor and a rotating shaft according to an embodiment of the present application; fig. 8 is a schematic view of a spreader according to an embodiment of the present application.

In some embodiments, as shown in fig. 1, 4, 7, and 8 in combination, the driving device 4 includes: a drive motor 41 provided on the second hanger body 121; a sprocket 42 provided with an output shaft of the driving motor; and a chain 43 engaged with the sprocket 42 and having both ends rotatably connected to the hoists 3.

Alternatively, the drive motor 41 may be a band-type brake motor of a model brake motor (low power) manufactured by yutong.

Alternatively, the sprocket 42 is provided on the rotating shaft 17, and the sprocket 42 is provided coaxially with the rotating shaft 17. The sprocket 42 may be welded to the spindle 17.

Alternatively, the chain 43 may be a roller chain, and other types of chains 43 such as a conveyor chain, a toothed chain, and the like may be used. For example, the roller chain may be a roller chain model 308563481_1565425660 manufactured by Saxiv.

Alternatively, the roller chain may be made of a metal material such as carbon steel, or may be made of a non-metal material such as polyethylene or nylon.

Optionally, the number of chains 43 is at least one or more. For example, the number of chains is two, or the number of chains is three, or the number of chains is four.

Alternatively, the driving motor 41 is disposed at one side of a second tab 1213, the driving motor 41 is fixed to the second tab 1213 by a screw, and the output shaft 411 of the driving motor is coaxially disposed with the rotation hole 13 of the second tab 1213. The output shaft 411 of the driving motor is connected with the rotating shaft 17, and the output shaft 411 of the driving motor and the rotating shaft 17 can be integrally formed by adopting the output shaft and the rotating shaft 17. The output shaft 411 of the drive motor may be regarded as the rotating shaft 17. The sprocket 42 is welded to the rotary shaft 17. One end of the chain 43 passes through the second hanging lug 1213 to form a second interlayer 1214, the middle part of the chain 43 is engaged with the sprocket 42, and both ends of the chain 43 are rotatably connected to the hanger 3.

Alternatively, the output shaft 411 of the driving motor is detachably connected with the rotating shaft 17. One end of the rotating shaft 17 is provided with a sliding groove 171, an output shaft 411 of the driving motor is provided with a clamping hole 412 matched with the rotating shaft 17, and the clamping connection between the output shaft 411 of the driving motor and the rotating shaft 17 is realized by arranging one end of the rotating shaft 17 with the sliding groove 171 in the clamping hole 412.

Alternatively, the driving device 4 can drive the suspended object 3 to rotate in any plane perpendicular to the end surface of the third end 1211.

When an operator needs to adjust the hanging object 3, the operator controls the driving motor 41 to rotate forward, the driving motor 41 drives the rotating shaft 17 to rotate, and the rotating shaft 17 rotates to drive the chain wheel 42 to rotate; when the sprocket 42 rotates, the chain 43 engaged with the sprocket 42 also rotates. The distance from one end of the chain 43 to the sprocket 42 gradually decreases with the rotation of the sprocket 42, and the distance from the other end of the chain 43 to the sprocket 42 gradually increases with the rotation of the sprocket 42. The suspended object 3 is changed from a horizontal state to an inclined state, and the inclined state of the suspended object 3 means that one end of the suspended object 3 is higher than the other end of the suspended object 3.

In this embodiment, the driving device is divided into four parts, namely a driving motor, a rotating shaft, a chain wheel and a chain, and when one part of the parts fails, only the failed part needs to be replaced. Set up drive arrangement on the second hoist subassembly, drive arrangement can carry out the secondary rotation adjustment to hanging the thing, has further strengthened the flexibility that the hoist was hoisted the thing hoist, has improved the degree of automation of hoist simultaneously.

Fig. 9 is an enlarged view of a portion a of fig. 1.

In some embodiments, as shown in fig. 2 and 9, the two ends of the chain 43 are hinged to the mounting portions of the suspended load 3.

Optionally, two pairs of mounting lugs 31 are integrally formed on one side surface of the hanger 3, and the two pairs of mounting lugs 31 are symmetrically arranged at two ends of the hanger 3. The two pairs of mounting lugs 31 on the lifting object 3 can be regarded as mounting parts of the lifting object 3. The pair of mounting lugs 31 includes two mounting lugs 31, and a mounting interlayer 32 is formed between the two mounting lugs 31. The mounting lug 31 may take the shape of an isosceles triangle. The mounting lug 31 is configured with a rotation hole 13. Both ends of the chain 43 are fixed in the same manner as the mounting lugs 31, so the example of fixing one end of the chain 43 and the mounting lugs 31 is described, one end of the chain 43 enters the mounting interlayer 32 formed by the two mounting lugs 31, the hole at one end of the chain 43 is coaxially arranged with the rotating hole 13 on the mounting lugs 31, the pin 14 passes through the rotating hole 13 of one mounting lug 31 and the hole at one end of the chain 43, and finally enters the rotating hole 13 of the other mounting lug 31, and the hinge joint of one end of the chain 43 and the mounting part of the hanger 3 is completed.

In this embodiment, articulate the chain and hang the thing, increased the flexibility that the second hoist subassembly hoisted the thing, to hanging the thing at the drive arrangement of second hoist subassembly and rotate the adjustment, the articulated department of chain and hanging the thing also can corresponding adjustment, has ensured the flexibility that the second hoist subassembly hoisted the thing.

FIG. 10 is a schematic illustration of a connection arrangement of a first spreader assembly, a second spreader assembly and a slewing device according to an embodiment of the present application; FIG. 11 is a schematic structural view of a first spreader assembly according to one embodiment of the present application; fig. 12 is a schematic structural view of a first spreader assembly according to one embodiment of the present application.

In some embodiments, as shown in fig. 10 to 12, the spreader 1 further includes: a slewing device 5, arranged on the first spreader assembly 11 and connected to the second spreader assembly 12, is configured to drive the second spreader assembly 12 in rotation.

In this embodiment, the second spreader component is rotated by the turning device, which improves the automation degree of the spreader.

Alternatively, as shown in fig. 10 to 12, the swiveling device 5 includes: a rotary motor 51 provided on the first spreader assembly 11; a first gear 52 provided on an output shaft 511 of the rotary motor; a second gear 53 disposed on the second spreader assembly 12 and coaxially disposed with the second spreader assembly 12; the second gear 53 meshes with the first gear 52.

Alternatively, the rotary electric machine 51 may employ a three-phase asynchronous motor model Y2, produced by double sails.

Optionally, a receiving cavity 1116 is configured within the first spreader body 111. The rotary motor 51 is fixed to the first end 1112 of the first hanger body 111 by a screw. A hole is configured on the first end 1112 through which the output shaft 511 of the rotary motor passes into the receiving cavity 1116 of the first spreader body 111. The first gear 52 and the second gear 53 are both disposed within the receiving cavity 1116. The first gear 52 is formed with a hole adapted to the output shaft 511 of the rotary motor, and the rotary motor 51 is engaged with the first gear 52 by disposing the output shaft in the hole of the first gear 52. The second gear 53 is provided coaxially with the first hanger body 111, and the first hanger body 111 is provided coaxially with the second hanger body 121. A fixing hole 531 is formed at a central position of the second gear 53. The second shaft body 1222 enters the fixing hole 531, completing the snap-fit engagement of the second gear 53 with the second hanger body 121.

In this embodiment, the degree of automation of hoist has been improved, simultaneously, divide into rotation motor, first gear, second gear triplex with rotation mechanism, when wherein some part breaks down, only need change the part that breaks down, has reduced the cost of maintenance in later stage. The first gear and the second gear are arranged in the accommodating cavity in the first lifting appliance main body, so that the matching degree of the first lifting appliance component and the second lifting appliance component is improved, and the whole structure of the lifting appliance is more compact.

FIG. 13 is a schematic view of a connection of a spreader to a lifting mechanism according to one embodiment of the present application; fig. 14 is a schematic view of a connection structure of a spreader and a lifting mechanism according to an embodiment of the present application.

According to a second aspect of the embodiment of the present application, as shown in fig. 13 and 14, the embodiment of the present application further provides a lifting mechanism 2, where the lifting mechanism 2 includes: the spreader 1 of any of the above alternative embodiments.

Alternatively, the lifting mechanism 2 may be a factory crown block, or a mobile crane.

Alternatively, the overhead crane of the plant may be an LX model overhead crane manufactured by descury crane (suzhou) limited.

Alternatively, the mobile crane may be a mobile crane of model SC10 available from mataka.

In this embodiment, when the suspended object needs to be adjusted in the air, the operator only needs to control the second spreader assembly to rotate relative to the first spreader assembly and the second spreader assembly to rotate the suspended object, so as to complete the adjustment of the attitude of the suspended object. The lifting appliance can enable the controllability of the lifting process to be stronger, and the posture adjusting mode of the lifted object to be more flexible. The lifting appliance has stronger environmental adaptability no matter the lifting appliance is used for lifting the lifting object in a factory or needs to be used for lifting the lifting object on a building site.

Alternatively, as shown in connection with figures 1, 13 and 14, the gripping portion 21 of the lifting mechanism 2 is detachably connected to the first spreader assembly 11.

Alternatively, the lifting structure of the crown block can adopt a power hoist of model PA200 produced by flying distance (hardware). The hook of the electric block can be regarded as the grip portion 21 of the lifting mechanism 2.

Alternatively, the hook of the mobile crane can be regarded as the gripping part 21 of the hoisting gear 2.

Alternatively, the hook enters the first interlayer 1114 of the first spreader assembly 11, and the hook is hooked to the pin 14 between the two first lifting lugs 1113, so that the connection of the lifting mechanism 2 and the spreader 1 is completed.

In this embodiment, want to be connected hoist and elevating system at operating personnel, operating personnel only need can accomplish hoist and elevating system with the round pin axle that elevating system's hook was hooked on the first hoist subassembly of hoist and is connected, and the operating personnel of being convenient for operates, has simplified the installation procedure, has improved work efficiency.

The above description and drawings sufficiently illustrate embodiments of the disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The examples merely typify possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in or substituted for those of others. The scope of the disclosed embodiments includes the full ambit of the claims, as well as all available equivalents of the claims. As used in this application, although the terms "first," "second," etc. may be used in this application to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without changing the meaning of the description, the first end may be called the second end, and likewise, the second end may be called the first end. Furthermore, the words used in the specification are words of description only and are not intended to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term "and/or" as used in this application is meant to encompass any and all possible combinations of one or more of the associated listed. Furthermore, the terms "comprises" and/or "comprising," when used in this application, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Without further limitation, an element defined by the phrase "comprising an …" does not exclude the presence of other like elements in a process, method or apparatus that comprises the element. In this document, each embodiment may be described with emphasis on differences from other embodiments, and the same and similar parts between the respective embodiments may be referred to each other. For the devices, structures, products, and the like of the embodiment disclosure, if they correspond to the devices, structures, and the like of the embodiment disclosure, the description of the devices, structures, and the like may be referred to in relevant places.

The embodiments of the present disclosure are not limited to the structures that have been described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A spreader, comprising:

a first spreader assembly including a first end connected to the lifting mechanism and a second end;

a second spreader assembly including a third end rotatably connected to the second end, and a fourth end removably connected to the pendant.

2. The spreader of claim 1,

the first end of the first spreader component includes a fixed portion connected to the lifting mechanism;

a bearing is disposed at the second end of the first spreader component.

3. The spreader of claim 2, wherein the second spreader assembly comprises:

a second hanger body having the third end connected with the bearing;

and the driving device is arranged at the fourth end of the second lifting appliance main body.

4. The spreader of claim 3, wherein the drive device comprises:

the driving motor is arranged on the second lifting appliance main body;

the chain wheel is arranged on an output shaft of the driving motor;

and the chain is meshed with the chain wheel, and both ends of the chain are rotatably connected to the hanging object.

5. The spreader of claim 4,

and two ends of the chain are respectively hinged with the mounting part of the hanging object.

6. The spreader of any one of claims 1 to 5, further comprising:

a slewing device disposed on the first spreader assembly and connected to the second spreader assembly and configured to drive the second spreader assembly in rotation.

7. The spreader of claim 6, wherein the slewing device comprises:

a rotary motor disposed on the first spreader component;

a first gear provided on an output shaft of the rotary motor;

a second gear disposed on the second spreader component and coaxially disposed with the second spreader component; the second gear is engaged with the first gear.

8. A lift mechanism, comprising:

the spreader of any one of claims 1 to 7.

9. The lift mechanism of claim 8,

the gripping portion of the lifting mechanism is detachably connected to the first spreader assembly.