CN211323801U

CN211323801U - Bookshelf for desk

Info

Publication number: CN211323801U
Application number: CN201921602713.XU
Authority: CN
Inventors: 方天龙
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2019-09-23
Filing date: 2019-09-23
Publication date: 2020-08-25
Anticipated expiration: 2029-09-23

Abstract

The present disclosure relates to a bookshelf for a table, the bookshelf comprising a body and a movable plate (4), the body comprising a bottom plate (1), a back plate (2), a left side plate (31) and a right side plate (32), the bottom plate (1), the back plate (2), the left side plate (31) and the right side plate (32) being assembled to define a book accommodating space, the movable plate (4) being disposed in the book accommodating space, and the movable plate (4) being connected to at least one of the bottom plate (1) and the back plate (2) through a sliding mechanism so as to be capable of translating left and right in the book accommodating space, and the movable plate (4) being releasably fixed to the body through a locking mechanism. Through above-mentioned technical scheme, this bookshelf for table that this disclosure provided can adjust the space that is used for placing books, and have sufficient stability.

Description

Bookshelf for desk

Technical Field

The disclosure relates to the field of bookshelves, in particular to a bookshelf for a table.

Background

The bookshelf is the indispensable furniture in the life official working, if the distance that is used for placing books on the bookshelf is fixed, if books are few and can not fill the bookshelf then, books empty easily, use inconvenient, consequently can be so that the interval that is used for placing books on the bookshelf is adjustable, improves the convenience of use. In the related art, there is a bookshelf formed by combining two movable L-shaped brackets, which is relatively simple, has poor stability, has low structural strength, and is easy to topple.

SUMMERY OF THE UTILITY MODEL

An object of the present disclosure is to provide a bookshelf for a table that can adjust a space for placing books and has sufficient stability.

In order to accomplish the above object, the present disclosure provides a bookshelf for a table, the bookshelf including a body including a bottom plate, a back plate, a left side plate and a right side plate assembled to define a book accommodating space, and a movable plate disposed in the book accommodating space and connected to at least one of the bottom plate and the back plate through a sliding mechanism to be capable of left and right translation in the book accommodating space, and releasably fixed to the body through a locking mechanism.

Optionally, the sliding mechanism includes a first sliding mechanism disposed between the back plate and the movable plate, the first sliding mechanism includes a first slider and a first guide rail disposed on the back plate, the first guide rail extends parallel to the bottom plate, the first slider is connected to the movable plate, and the first slider is movably connected to the first guide rail and can slide along the first guide rail.

Optionally, the first guide rail is configured as a sliding slot having a T-shaped cross section to constrain the first slider in the sliding slot.

Optionally, the first slider includes a pulley pivotally connected to the connecting bracket by an axle and a connecting bracket, the pulley is disposed in the sliding groove in a sliding fit, and the connecting bracket is connected to the movable plate by a fastener.

Optionally, the connecting bracket is configured as a U-shaped bracket, and includes two parallel end portions and an intermediate connecting portion, the movable plate extends between the two end portions, and the connecting bracket and the movable plate are fixed together by the fastening member passing through the end portions and the mounting holes on the movable plate.

Optionally, the sliding mechanism includes a second sliding mechanism disposed between the movable plate and the bottom plate, the second sliding mechanism includes a second slider and a second guide rail disposed on the bottom plate, the second guide rail extends parallel to the back plate, the second slider is connected to the movable plate, and the second slider is movably connected to the second guide rail and is capable of sliding along the second guide rail.

Optionally, a cantilever extending in a direction of the second slider is connected to the movable plate, and the locking mechanism includes a locking member connecting the second slider and the cantilever and releasably fixing the cantilever and the second rail together.

Optionally, the lock is configured with a screw portion, a stopper portion and an operating handle, the lock mechanism includes a threaded hole formed on the second slider, the cantilever is provided with a through hole through which the screw portion is fitted in the threaded hole, the stopper portion has a lateral dimension larger than a bore diameter of the through hole, so that the stopper portion can press the cantilever against the second rail by screwing of the screw portion in the threaded hole to fix the cantilever with the second rail, and the stopper portion can release the cantilever by unscrewing of the screw portion in the threaded hole to release the fixation between the cantilever and the second rail.

Optionally, the screw portion and the limiting portion are configured together as a T-shaped structure, the through hole includes a large diameter portion and a small diameter portion, a step surface is configured between the large diameter portion and the small diameter portion, and the limiting portion is located in the large diameter portion and has a transverse dimension larger than a bore diameter of the small diameter portion so as to be capable of abutting against the cantilever through a stopper of the step surface.

Optionally, the cantilever is connected to the movable plate by a pin.

Optionally, the cantilever is resilient.

Optionally, the second guide rail is fixed to a lower surface of the base plate and configured with a guide groove in which the second slider is accommodated, and the guide groove can restrict the second slider from rotating together with the screw portion.

Optionally, the desk bookshelf comprises a support member connected to the lower surface of the bottom plate.

Optionally, the support member includes two strip-shaped support blocks, the left end and the right end of the body are both provided with one support block, each support block and the bottom plate are provided with angle irons, the angle irons and the support blocks are connected through fasteners, and the angle irons and the bottom plate are connected through other fasteners.

Through above-mentioned technical scheme, the fly leaf can slide for the body of bookshelf through slide mechanism in books accommodation space to can adjust self relative position for the body according to the actual required space of books, and keep the rigidity through locking mechanism, can make books place steadily. Therefore, the desk bookshelf provided by the disclosure can adjust the space for placing books and has sufficient stability.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

fig. 1 is a perspective view of a desk bookshelf provided in accordance with some embodiments of the present disclosure;

fig. 2 is a perspective view from another perspective of a desk bookshelf provided in accordance with some embodiments of the present disclosure;

FIG. 3 is a top view of a desk bookshelf provided in accordance with some embodiments of the present disclosure;

FIG. 4 is a cross-sectional view taken along line A-A of FIG. 3;

FIG. 5 is an enlarged view of portion B of FIG. 4;

fig. 6 is a perspective view of the combination of the cantilever, the locking member and the second slider of the bookshelf for a table provided by some embodiments of the present disclosure;

fig. 7 is a perspective view of a first slider of a bookshelf for a table provided according to some embodiments of the present disclosure.

Description of the reference numerals

1-bottom plate, 2-back plate, 31-left side plate, 32-right side plate, 4-movable plate, 40-pin shaft, 41-cantilever,

5-a first slide block, 51-a pulley, 52-a connecting bracket, 53-a wheel shaft, 6-a first guide rail,

7-a second slide block, 8-a second guide rail, 91-a screw rod part, 92-a limiting part, 93-an operating handle,

10-supporting blocks and 11-angle iron.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

In the present disclosure, the use of directional words such as "upper, lower, front, rear, left, right" may refer specifically to the designations in fig. 1, unless stated to the contrary. The terms "first," "second," and the like, as used in this disclosure, are intended to distinguish one element from another, and not necessarily for sequential or importance. Furthermore, in the following description, when referring to the figures, the same reference numbers in different figures denote the same or similar elements, unless otherwise explained. The foregoing definitions are provided to illustrate and describe the present disclosure only and should not be construed to limit the present disclosure.

According to some embodiments of the present disclosure, the present disclosure provides a bookshelf for a table, the bookshelf comprising a body and a movable plate 4, the body comprising a bottom plate 1, a back plate 2, a left side plate 31 and a right side plate 32, the bottom plate 1, the back plate 2, the left side plate 31 and the right side plate 32 being assembled to define a book accommodating space, the movable plate 4 being disposed in the book accommodating space, and the movable plate 4 being connected to at least one of the bottom plate 1 and the back plate 2 through a sliding mechanism so as to be capable of left and right translation in the book accommodating space, and the movable plate 4 being releasably fixed to the body through a locking mechanism.

Through above-mentioned technical scheme, fly leaf 4 can slide for the body of bookshelf through slide mechanism in books accommodation space to can adjust self relative position for the body according to the actual required space of books, and keep the rigidity through locking mechanism, can make books place steadily. Therefore, the desk bookshelf provided by the disclosure can adjust the space for placing books and has sufficient stability.

Wherein, backplate 2 all extends along the length direction of desk bookshelf with bottom plate 1, also extend along left right direction, backplate 2 is connected perpendicularly in the rear side of bottom plate 1, left side board 31 and right side board 32 all perpendicular to length direction set up, left side board 31 is connected in the left end of backplate 2 and bottom plate 1 in the left side of body, right side board 32 is connected in the right-hand member of backplate 2 and bottom plate 1 on the right side of body, fly leaf 4 sets up perpendicularly on bottom plate 1, and perpendicular with length direction, under slide mechanism and locking mechanism's effect, the distance between fly leaf 4 and left side board 31 and the right side board 32 is adjustable.

According to some embodiments of the present disclosure, as shown in fig. 1 to 4, the sliding mechanism includes a first sliding mechanism disposed between the back plate 2 and the movable plate 4, the first sliding mechanism includes a first slider 5 and a first guide rail 6 disposed on the back plate 2, the first guide rail 6 extends parallel to the bottom plate 1, the first slider 5 is connected to the movable plate 4, and the first slider 5 is movably connected to the first guide rail 6 and can slide along the first guide rail 6. Thus, the movable plate 4 and the first slider 5 slide along a direction extending parallel to the base plate 1 under the guiding action of the first guide rail 6, thereby achieving the left-right translation of the movable plate 4 in the book accommodating space.

The first guide rail 6 may be configured in any suitable manner, and according to some embodiments of the present disclosure, as shown in fig. 4, the first guide rail 6 may be configured as a chute having a T-shaped cross section to restrain the first slider 5 therein. Alternatively, a T-shaped slide groove may be formed on the front side surface of the back plate 2 in the left-right direction to form the first guide rail 6, and the first slider 5 may slide left and right in the slide groove. For convenience of manufacture and installation, the T-shaped chute may penetrate through left and right side surfaces of the back plate 2, and the left and right side surfaces of the back plate 2 may abut against the left and

right side plates

31 and 32, respectively, so that both ends of the T-shaped chute may be sealed by the left and

right side plates

31 and 32, the first slider 5 is prevented from being removed, and the back plate 2 may be fixed with the left and

right side plates

31 and 32 by using screws as shown in fig. 1 and 2.

According to some embodiments of the present disclosure, as shown in fig. 7, the first slider 5 includes a pulley 51 and a connecting bracket 52, the pulley 51 is pivotally connected to the connecting bracket 52 by an axle 53, the pulley 51 is slidably disposed in the sliding groove, and the connecting bracket 52 is connected to the movable plate 4 by a fastener. Therefore, the pulley 51 can rotate around the wheel shaft 53, when the movable plate 4 is pushed by hand to move horizontally left and right, the pulley 51 rolls in the sliding groove, the friction resistance is small, the adjustment is convenient, and the smooth translation of the movable plate 4 is facilitated. Of course, the first slider 5 may be configured in other structures, such as a block-shaped slider, which is not limited herein.

Alternatively, as shown in fig. 7, the connecting bracket 52 may be configured as a U-shaped bracket including two parallel end portions and an intermediate connecting portion, the movable plate 4 is inserted between the two end portions, and the connecting bracket 52 and the movable plate 4 are fixed together by fastening members through the end portions and the mounting holes of the movable plate 4. Thus, the connection strength between the U-shaped connecting bracket 52 and the movable plate 4 is high, and the reliability is good. In addition, the wheel shaft 53 can be connected to the outer side of the middle connecting part, and the pulley 51 is installed on the wheel shaft 53, so that the structure is simple, and the connecting strength is high.

According to some embodiments of the present disclosure, as shown in fig. 7, the sliding mechanism includes a second sliding mechanism disposed between the movable plate 4 and the bottom plate 1, the second sliding mechanism includes a second slider 7 and a second rail 8 disposed on the bottom plate 1, the second rail 8 extends parallel to the back plate 2, the second slider 7 is connected to the movable plate 4, and the second slider 7 is movably connected to the second rail 8 and can slide along the second rail 8. In this way, the movable plate 4 and the second slider 7 can slide in the left-right direction under the guiding action of the second guide rail 8, thereby achieving the left-right translation of the movable plate 4 in the book accommodating space.

According to some embodiments of the present disclosure, as shown in fig. 1 to 6, a cantilever 41 extending toward the direction in which the second slider 7 is located is attached to the movable plate 4, and the locking mechanism includes a lock that connects the second slider 7 and the cantilever 41 and releasably fixes the cantilever 41 and the second rail 8 together. Wherein, the lower end of the movable plate 4 is spaced from the bottom plate 1 to form a gap, so as to prevent the movable plate 4 from generating friction force with the bottom plate 1 and affecting the left-right translation of the movable plate 4. One end of the cantilever 41 is connected to the movable plate 4, and the other end is connected to the second slider 7 through a locking member, so that the movable plate 4 can move along with the second slider 7. The second slider 7 is located in the slide way of the second guide rail 8, and the cantilever 41 can be fixed on the second guide rail 8 by locking and unlocking the locking member, that is, the position of the movable plate 4 is fixed, and the cantilever 41 can be released to move relative to the second guide rail 8 after the locking member is unlocked, so that the distance between the movable plate 4 and the left side plate 31 and the right side plate 32 can be adjusted, books can be stably placed in the space between the movable plate 4 and the left side plate 31 or the right side plate 32, and the books are prevented from being toppled randomly. In other embodiments of the present disclosure, the locking member may be disposed at the first rail 6, which is not limited herein.

The lock may be configured in any suitable manner, according to some embodiments of the present disclosure, as shown in fig. 5 and 6, the lock is configured with a screw portion 91, a stopper portion 92, and an operating handle 93, the lock mechanism includes a threaded hole formed on the second slider 7, the suspension arm 71 is provided with a through hole through which the screw portion 91 is fitted, the stopper portion 92 has a lateral dimension larger than a hole diameter of the through hole to enable the stopper portion 92 to press the suspension arm 41 against the second rail 8 by screwing of the screw portion 91 in the threaded hole to fix the suspension arm 41 and the second rail 8 together, and to enable the stopper portion 92 to release the suspension arm 41 by unscrewing of the screw portion 91 in the threaded hole to release the fixation between the suspension arm 41 and the second rail 8. In other words, the screw portion 91 can be rotated by manipulating the operation knob 93 so that the screw portion 91 can be screwed into or out of the second slider 7, and by the restriction effect of the second rail 8 on the second slider 7, the distance between the stopper portion 92 and the second slider 7 can be changed accordingly during the rotation of the screw portion 91, so that the suspension arm 41 can be pressed against the second rail 8 or the pressing can be released, and the movable plate 4 can be locked on the second rail 8 or can be translated left and right by the generation and release of the frictional force between the suspension arm 41 and the second rail 8. Further, providing the stopper portion 92 between the arm 41 and the operating knob 93 can increase the distance between the operating knob 93 and the arm 41, thereby increasing the space to facilitate the operation of the operating knob 93.

Alternatively, as shown in fig. 5, the screw portion 91 and the stopper portion 92 may be configured together in a T-shaped structure, the through hole includes a large diameter portion and a small diameter portion between which a step surface is configured, and the stopper portion 92 is located in the large diameter portion and has a lateral dimension larger than the aperture of the small diameter portion so as to be able to abut against the cantilever 41 by a stopper of the step surface. Like this, spacing portion 92 can hold on the major diameter portion of the through-hole of seting up on cantilever 41, like this, can reduce the size that the retaining member stretches out cantilever 41, the shared space size of retaining member for whole bookshelf structure is neat.

Alternatively, as shown in fig. 5 and 6, the cantilever 41 may be connected to the movable plate 4 by a pin 40. In this way, the cantilever 41 can rotate relative to the movable plate 4 about the pin 40, and the end of the cantilever 41 facing the second slider 7 has a corresponding range of motion, thereby facilitating the releasable pressing of the end of the cantilever 41 facing the second slider 7 against the second rail 8 by the action of the locking member.

Alternatively, the cantilever 41 may have elasticity. The movable range of the suspension 41 toward the end of the second slider 7 when pressed or released by the stopper portion 92 is accommodated by the elastic deformation of the suspension 41.

In consideration of the problems of manufacturing cost, weight and the like, the bookshelf body is generally made of non-metal materials, but because the locking mechanism is arranged at the second guide rail 8, the locking force generated at the matching position between the locking mechanism and the second guide rail 8 can resist the tilting force of the book on the movable plate 4 so as to ensure that the movable plate 4 is at the fixed position, and then the second guide rail 8 needs to have higher rigidity and strength. Therefore, in the present disclosure, as shown in fig. 5, the second guide rail 8 may be a separately provided one having a large strength and rigidity mounted on the base plate 1, the second guide rail 8 may be fixed to a lower surface of the base plate 1 and configured with a guide groove in which the second slider 7 is accommodated, and the guide groove may restrict the second slider 7 from rotating together with the screw part 91. Alternatively, the cross section of the second rail 8 may be configured in an H-shape, so that the second rail 8 has two grooves, and the front side of the base plate 1 may be inserted into one of the grooves and fixed by a corresponding fastener, so that the strength of the joint of the second rail 8 and the base plate 1 may be increased; the other recess opens forward and is formed as a guide groove for receiving the second slider 7, and the suspension arm 41 is connected to the front side of the movable plate 4 and extends downward to the front of the second rail 8 so as to be pressed against the second rail 8 by the locking member, and a locking force is generated by a frictional force between the suspension arm 41 and the second rail 8 to lock the movable plate 4. Alternatively, the second rail 8 is a metal rail. Of course, in other embodiments, the bookshelf body or the bottom plate 1 may be made of a metal material to increase the structural strength, and the second rail 8 may also be formed by a groove formed on the bottom plate 1, which is not limited herein.

According to some embodiments of the present disclosure, as shown in fig. 1, the bookshelf for table may include a support member attached to a lower surface of the base plate 1. The lower surface of the base plate 1 has a space between the table tops, and the above-mentioned operating handle 93 can be easily adjusted when the locking member is provided at the second guide rail 8.

Alternatively, as shown in fig. 2, the support member may include two strip-shaped support blocks 10, a support block 10 is provided at each of left and right ends of the body, each support block 10 and the base plate 1 is provided with an angle iron 11, the angle iron 11 and the support block 10 are connected by a fastener, and the angle iron 11 and the base plate 1 are connected by another fastener. Wherein, a side of angle bar 11 laminates with the downside of bottom plate 1 mutually, and another side laminates with the medial surface of supporting shoe 10 mutually, and the lateral surface of two supporting shoes 10 can be respectively with the lateral surface parallel and level of left side board 31 and right side board 32, and like this, angle bar 11 hides in the below of bottom plate 1, can improve the pleasing to the eye of bookshelf, can increase the joint strength between supporting shoe 10 and the bottom plate 1 moreover, does benefit to and improves the holistic structural strength of bookshelf. The fastener can be a screw as shown in fig. 5, and has the advantages of simple structure, convenient operation and low cost. Of course, the support block 10 may also be disposed below the middle of the bottom plate 1 when the length of the bottom plate 1 is long.

In addition, in order to reduce the weight of the bookshelf, the left side plate 31, the right side plate 32 and the front upper side of the movable plate 4 can be provided with inclined surfaces, so that the appearance of the bookshelf can be improved. As shown in FIG. 1, holes suitable for two hands to insert may be formed on the left side plate 31 and the right side plate 32 to facilitate the two hands to insert into the holes for carrying the bookshelf.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. A bookshelf for a table, characterized in that the bookshelf comprises a body and a movable plate (4), the body comprises a bottom plate (1), a back plate (2), a left side plate (31) and a right side plate (32), the bottom plate (1), the back plate (2), the left side plate (31) and the right side plate (32) are assembled to define a book accommodating space, the movable plate (4) is disposed in the book accommodating space, and the movable plate (4) is connected to at least one of the bottom plate (1) and the back plate (2) through a sliding mechanism so as to be capable of translating left and right in the book accommodating space, and the movable plate (4) is releasably fixed to the body through a locking mechanism.

2. A desk bookshelf according to claim 1 wherein the sliding mechanism comprises a first sliding mechanism arranged between the back plate (2) and the movable plate (4), the first sliding mechanism comprises a first slider (5) and a first guide rail (6) arranged on the back plate (2), the first guide rail (6) extends parallel to the bottom plate (1), the first slider (5) is connected to the movable plate (4), and the first slider (5) is movably connected to the first guide rail (6) and can slide along the first guide rail (6).

3. A desk bookshelf according to claim 2 wherein the first rail (6) is configured as a chute having a T-shaped cross-section to constrain the first slider (5) in the chute.

4. A desk bookshelf according to claim 3 wherein the first slider (5) comprises a pulley (51) and a connecting bracket (52), the pulley (51) being pivotally connected to the connecting bracket (52) by an axle (53), the pulley (51) being slidably fitted in the sliding slot, the connecting bracket (52) being connected to the movable plate (4) by a fastener.

5. A desk bookshelf according to claim 4 wherein the connecting bracket (52) is configured as a U-shaped bracket comprising two parallel ends and an intermediate connecting part, the movable plate (4) extending between the two ends, the connecting bracket (52) and the movable plate (4) being fixed together by the fasteners passing through the ends and the mounting holes on the movable plate (4).

6. A desk bookshelf according to claim 1 wherein the sliding mechanism comprises a second sliding mechanism arranged between the movable plate (4) and the base plate (1), the second sliding mechanism comprising a second slider (7) and a second guide rail (8) arranged on the base plate (1), the second guide rail (8) extending parallel to the back plate (2), the second slider (7) being connected to the movable plate (4), and the second slider (7) being movably connected to the second guide rail (8) and being slidable along the second guide rail (8).

7. A desk bookshelf according to claim 6 wherein a cantilever (41) extending towards the direction of the second slider (7) is connected to the movable plate (4), and the locking mechanism comprises a locking member connecting the second slider (7) and the cantilever (41) and releasably securing the cantilever (41) and the second rail (8) together.

8. A desk bookshelf according to claim 7 wherein the locking piece is configured with a screw part (91), a position-limiting part (92) and an operating handle (93), the locking mechanism comprises a threaded hole formed on the second slider (7), the suspension arm (41) is provided with a through hole through which the screw part (91) fits in the threaded hole, the position-limiting part (92) has a lateral dimension larger than the aperture of the through hole so that the position-limiting part (92) can press the suspension arm (41) against the second rail (8) by tightening of the screw part (91) in the threaded hole, thereby fixing the suspension arm (41) and the second rail (8) together, and the position-limiting part (92) can release the suspension arm (41) by loosening of the screw part (91) in the threaded hole, thereby releasing the fixation between the cantilever 41 and the second rail 8.

9. A desk bookshelf according to claim 8 wherein the screw part (91) and the stopper part (92) together are configured as a T-shaped structure, the through hole comprises a large diameter part and a small diameter part, a step surface is configured between the large diameter part and the small diameter part, and the stopper part (92) is located in the large diameter part and has a lateral dimension larger than the aperture of the small diameter part so as to be able to abut against the cantilever (41) by a stop of the step surface.

10. A desk bookshelf according to claim 8 wherein the cantilever (41) is connected to the movable plate (4) by a pin (40).

11. A desk bookshelf according to claim 8 wherein the cantilever arms (41) are resilient.

12. A desk bookshelf according to claim 8, wherein the second guide rail (8) is fixed on the lower surface of the bottom plate (1) and is configured with a guide groove, the second slider (7) is accommodated in the guide groove, and the guide groove can restrict the second slider (7) from rotating together with the screw part (91).

13. A desk bookshelf according to any one of the claims 1-12 wherein the desk bookshelf comprises a support member connected to the lower surface of the base plate (1).

14. A desk bookshelf according to claim 13 wherein the support member comprises two strip-shaped support blocks (10), the left and right ends of the body are each provided with a support block (10), each support block (10) and the base plate (1) are provided with an angle iron (11), the angle irons (11) and the support blocks (10) are connected by fasteners, and the angle irons (11) and the base plate (1) are connected by further fasteners.