CN218813751U

CN218813751U - Length-adjustable support

Info

Publication number: CN218813751U
Application number: CN202223138189.XU
Authority: CN
Inventors: 张家广; 张远泽
Original assignee: China Construction Communications Engineering Group Co Ltd
Current assignee: China Construction Communications Engineering Group Co Ltd
Priority date: 2022-11-25
Filing date: 2022-11-25
Publication date: 2023-04-07
Anticipated expiration: 2032-11-25

Abstract

The application discloses adjustable length pillar includes: the first outer sleeve fixed ejector rod and the first inner sleeve movable ejector rod; the first outer sleeve fixing ejector rod is of a hollow structure; the first end is provided with a connecting part which is used for connecting the supporting sheet or the pillar; the first end of the first inner sleeve movable ejector rod is inserted into the first outer sleeve fixed ejector rod through the second end of the first outer sleeve fixed ejector rod; the insertion depth is adjustable so as to adjust the length of the length-adjustable strut; the second end of the movable ejector rod of the first inner sleeve is provided with a connecting part, and the connecting part is used for connecting adjacent struts or support pieces. The length-adjustable support can be arranged in the support in the mud pit and used for supporting two opposite sides of the support, and the support can be enabled to form powerful support for the two opposite sides of the support due to the fact that the length of the support can be adjusted, and looseness of the support is avoided. Thereby be favorable to improving the fastness of whole support, improve the protection support effect of support, be favorable to improving constructor's security in the mud pit.

Description

Length-adjustable support

Technical Field

The application relates to the technical field of installation engineering, in particular to a length-adjustable strut.

Background

In the related art, a longitudinal and transverse drainage ditch foundation pit between lines in a railway station and an electrified contact net support rectangular foundation pit are constructed only by adopting a manual vertical excavation mode because the foundation pit is close to a line, has large depth and narrow working surface, and cannot adopt mechanical excavation. If when the hole is darker, can take place very probably that the earth on the arm of digging drops and collapses, brings the personal safety hidden danger for the operating personnel, if only adopt traditional support to support the arm of digging, after long-time, the support is probably not hard up, drops, supports the protective effect and remains the improvement.

SUMMERY OF THE UTILITY MODEL

The main object of the present application is to provide a length adjustable prop to solve the above problems.

In order to achieve the above object, according to one aspect of the present application, there is provided a length-adjustable strut including: the first outer sleeve fixed ejector rod and the first inner sleeve movable ejector rod;

the first outer sleeve fixing ejector rod is of a hollow structure; the first end is provided with a connecting part which is used for connecting the supporting sheet or the supporting column;

the first end of the first inner sleeve movable ejector rod is inserted into the first outer sleeve fixed ejector rod through the second end of the first outer sleeve fixed ejector rod; the insertion depth is adjustable so as to adjust the length of the length-adjustable strut;

the second end of the movable ejector rod of the first inner sleeve is provided with a connecting part, and the connecting part is used for connecting adjacent struts or support pieces.

In one embodiment, a second transmission mechanism is further included, the second transmission mechanism including: a second ratchet mechanism and a force transmission rack;

the second ratchet mechanism includes at least: a gear, a gear seat and a ratchet shaft;

the gear seat is fixedly arranged on the first outer sleeve fixing ejector rod; the gear is arranged on the gear seat, and the ratchet shaft is sleeved in the middle of the gear;

the force transmission rack is fixed on the movable ejector rod of the first inner sleeve and is matched with the teeth of the gear;

when the length is adjusted, a ratchet wrench is sleeved on the ratchet shaft, the ratchet wrench is rotated, the ratchet shaft rotates, the ratchet shaft drives the gear to rotate, and the gear drives the force transmission rack to move; the force transmission rack drives the first inner sleeve movable ejector rod to go deep into or extend out of the first outer sleeve fixed ejector rod so as to adjust the length of the length-adjustable strut.

In one embodiment, the method further comprises: the handle comprises a handle, two handle ears are arranged at one end of the handle, the two handle ears are arranged oppositely, and a bidirectional ratchet wheel is arranged in each handle ear;

when the length of the handle is adjusted, the handle is rotated, the handle drives the ratchet shaft to rotate through the bidirectional ratchet wheel in the handle ear, the ratchet shaft drives the gear to rotate, and the gear drives the force transmission rack to move; the force transmission rack drives the first inner sleeve movable ejector rod to go deep into or extend out of the first outer sleeve fixed ejector rod so as to adjust the length of the length-adjustable strut.

In one embodiment, the handle is adjustable in length.

In one embodiment, the first end of the first outer sleeve fixing ejector rod is provided with a groove, and the width of the groove is matched with the width of a rib pipe of the support piece and is used for being inserted onto the rib pipe so as to fix the length-adjustable strut.

In one embodiment, the connecting portion is provided with a through hole, and the connecting portion is connected by a bolt.

In one embodiment, the material of the first outer sleeve fixed ejector rod and the first inner sleeve movable ejector rod is aluminum alloy.

According to the technical scheme, the length-adjustable strut comprises a first outer sleeve fixed ejector rod and a first inner sleeve movable ejector rod; the first outer sleeve fixing ejector rod is of a hollow structure; the first end is provided with a connecting part which is used for connecting the supporting sheet or the supporting column; the first end of the first inner sleeve movable ejector rod is inserted into the first outer sleeve fixed ejector rod through the second end of the first outer sleeve fixed ejector rod; the insertion depth is adjustable to adjust the length of the length adjustable strut. The length-adjustable strut can be arranged in the support in the mud pit and used for supporting two opposite sides of the support, so that the firmness of the whole support is improved. In some special required scenes, for example, in scenes of longitudinal and transverse drainage ditch foundation pits between lines in a railway station and rectangular foundation pits of an electrified contact net support column, effective and rapid supporting protection can be carried out on a vertical pit arm, and the personal safety of constructors and the railway transportation safety are improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, serve to provide a further understanding of the application and to enable other features, objects, and advantages of the application to be more apparent. The drawings and the description of the exemplary embodiments of the present application are provided for explaining the present application and do not constitute an undue limitation on the present application. In the drawings:

FIG. 1 is a top view of an adjustable length stem lift according to an embodiment of the present application;

FIG. 2 is a side view of an adjustable length ram according to an embodiment of the present application;

FIG. 3 is a partial view of an adjustable length stem lifter according to an embodiment of the present application;

FIG. 4 is a schematic view of a stop mechanism according to an embodiment of the present application;

FIG. 5 is a top view of a grooved, adjustable length ram according to an embodiment of the present application;

FIG. 6 is a top view of another length adjustable ram according to an embodiment of the present application;

FIG. 7 is a schematic view of a fixed length ram according to an embodiment of the present application;

FIG. 8 is a top view of a grooved length fixed ram according to an embodiment of the present application;

FIG. 9 is a top view of a pit arm support according to an embodiment of the present application;

FIG. 10 is a schematic view of a square tube and connector according to an embodiment of the present application.

Description of the reference numerals

001-length adjustable support piece; 002-length fixing support plate; 003-length adjustable ejector pin; 004-length fixing ejector rods; 005-square tube; 0051-attachment; 101-a first outer sleeve fixing ejector rod; 1010-through holes; 102-a first inner sleeve movable mandril; 103-a connecting portion; 1031-through holes; 104-a second transmission mechanism; 1041-a second ratchet; 10411-a gear; 104111-a non-return pawl; 10415-stop seat; 10416-stop pawl shaft; 10412-gear seat; 10413-a handle; 10414-handle ear; 1042-a force transmitting rack; 10415-a reversing handle; 10416-ratchet shaft; 105-a groove; 106-reinforcing plate; 1101-a mandril; 1102-a connecting part; 1103-reinforcing ribs; 1104-grooves.

Detailed Description

In order to make the technical solutions of the present application better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In the present application, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", and the like indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These terms are used primarily to better describe the invention and its embodiments, and are not intended to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.

Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meaning of these terms in the present invention can be understood by those of ordinary skill in the art as appropriate.

Furthermore, the terms "mounted," "disposed," "provided," "connected," and "sleeved" are to be construed broadly. For example, it may be a fixed connection, a removable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

In a first aspect, the present application provides a length-adjustable roof bar 003, referring to fig. 1, including: a first outer sleeve fixed top bar 101 and a first inner sleeve movable top bar 102. The first outer sleeve fixing ejector rod 101 is of a hollow structure; the first end is provided with a connecting part, and the connecting part is used for connecting a support piece or a support column. The first end of the first inner sleeve movable ejector rod 102 is inserted into the first outer sleeve fixed ejector rod 101 through the second end of the first outer sleeve fixed ejector rod 101; the insertion depth is adjustable to adjust the length of the length adjustable strut. The second end of the first inner sleeve movable top rod 102 is provided with a connecting part 103, and the connecting part 103 is used for connecting adjacent struts or support pieces. The first outer sleeve fixed ejector rod 101 and the first inner sleeve movable ejector rod 102 can be implemented by using a rigid pipe.

In some embodiments, referring to fig. 2, the connecting portion 103 is provided with a through hole 1031 for connecting adjacent rods by a connecting member.

In some embodiments, a rib 106 may be further provided, one end of which is connected to the connecting portion 103, and one end of which is fixed on the surface of the first outer fixing post 101, for reinforcing the compressive strength of the connecting portion 103.

In one embodiment, referring to fig. 2 and 3, a second transmission mechanism 104 is further included, the second transmission mechanism 104 including: a second ratchet mechanism 1041 and a force transmitting rack 1042.

The second ratchet mechanism 1041 at least includes: the second ratchet mechanism includes at least: gear 10411, gear seat 10412, ratchet shaft 10416. The gear seat 10412 is fixedly arranged on the first outer sleeve fixing ejector rod; the gear 10411 is arranged on the gear base 10412, and the ratchet shaft 10416 is sleeved in the middle; the force transmission rack 1042 is fixed on the movable top rod of the first inner sleeve and is matched with the teeth of the gear 10411. Wherein, a bearing can be arranged in the gear base 10412, an inner sleeve of the bearing is sleeved on the ratchet shaft 10416, and an outer sleeve of the bearing is fixedly arranged in the gear base 10412. The gear seat 10412 serves as a support. Thus, the ratchet shaft 10416 and the gear 10411 can be rotated flexibly. The force transmission rack 1042 is fixed on the first inner sleeve movable top rod 102 and is engaged with the teeth of the gear 10411 in a matching way. If the first outer sleeve fixing top rod 101 is a square tube, an opening is further required to be formed in a relevant position of a first side surface of the square tube, where the first side surface is used for arranging the second transmission mechanism 104, so that the teeth of the gear 10411 can be in contact engagement with the force transmission rack 1042, the opening may be formed in the middle of the first side surface, and gear seats 10412 may be respectively formed at edges of the first side surface, which are respectively in contact with two adjacent vertical surfaces. The gear seat 10412 may be fixed to the edge by welding. Gear 10411 may have its own check pawl 104111 for preventing reverse movement of gear 10411.

When the length is adjusted, a ratchet wrench is sleeved on the ratchet shaft, the ratchet shaft rotates when the ratchet wrench is rotated, the ratchet shaft drives the gear to rotate, and the gear drives the force transmission rack to move; the force transmission rack drives the first inner sleeve movable ejector rod to go deep into or extend out of the first outer sleeve fixed ejector rod so as to adjust the length of the length-adjustable strut.

The method uses the existing ratchet wrench, the existing ratchet wrench is provided with the bidirectional ratchet, the ratchet shaft is screwed by the ratchet wrench to rotate, so that the force transmission rack is driven to move through the gear, the first inner sleeve is driven to move, the movable ejector rod is driven to stretch and retract, the length is adjusted, and a constructor can adjust the length simply and conveniently by carrying one ratchet wrench.

The ratchet wrench can also be configured to be directly disposed on the first outer fixed ram, in one embodiment, further comprising: the handle 10413, two handle ears 10414 that one end of the handle 10413 set up, two handle ears 10414 set up relatively, be equipped with second ratchet 1041 in each handle ear 10414, second ratchet 1041 is two-way ratchet. The second ratchet wheel 1041 is nested inside the handle ear 10414; the ratchet shaft 10416 is sleeved in the middle.

When the length is adjusted, the handle 10413 is rotated, the handle drives the ratchet shaft 10416 to rotate through the bidirectional ratchet 1041 in the handle ear 10414, the ratchet shaft 10416 drives the gear to rotate, and the gear drives the force transmission rack to move; the force transmission rack drives the first inner sleeve movable ejector rod 102 to go deep into or extend out of the first outer sleeve fixed ejector rod 101, so that the length of the device can be adjusted.

In one embodiment, the length of the handle 10413 is adjustable. The length of the handle 10413 is adjusted to be long, so that the handle can be rotated more labor-saving, and labor is saved.

A reversing handle 10415 may be further disposed on the handle ear 10414 for reversing.

In some embodiments, referring to fig. 4, a stopping mechanism is further provided, and the stopping mechanism includes the above-mentioned check pawl 104111, a stopping seat 10415 provided on the above-mentioned first outer sleeve fixing ejector 101, a stopping pawl shaft 10416 is provided on the stopping seat 10415, the above-mentioned check pawl 104111 is sleeved on the stopping pawl shaft 10416, and the check pawl 104111 can rotate around the stopping pawl shaft 10416, and is adjusted in position to realize stopping. As shown in the figure, the non-return pawl 104111 is adjusted to a position contacting with the force transmission rack, and the angle between the central axis of the non-return pawl 104111 and the force transmission rack is an obtuse angle, so that the function of stopping can be achieved, the force transmission rack is prevented from moving leftwards, but the force transmission rack can move rightwards. If no stopping is required, the check pawl 104111 may be repositioned to disengage from contact with the force transfer rack.

Referring to fig. 5, in one embodiment, a slot 105 may be further formed at one end of the length-adjustable ejector rod, the slot 105 is a through slot, and the width of the slot 105 is matched with the width of the rib tube of the support piece, and may be set to be in clearance fit. Thus, during installation, the rib tube of the support piece can be embedded into the groove 105 sleeve to play a role in fixing the length-adjustable ejector rod.

In one embodiment, referring to fig. 6, the first outer sleeve fixed post 101 and the first inner sleeve movable post 102 are oppositely provided with a plurality of through holes 1010, and are connected through a connecting member.

The first outer sleeve fixing ejector rod and the first inner sleeve movable ejector rod are oppositely provided with a plurality of through holes, so that connecting pieces can be used for connection, and the connecting pieces can be bolts and nuts. The regulation is convenient, only need artificial demand according to the actual building site scene, adjust length can, distance between a plurality of through-holes can set for in a flexible way, for example, can set for 2 centimetres, 5 centimetres etc..

In a second aspect, the present application also proposes a length-fixed push rod, which is not adjustable in length and is not provided with a transmission mechanism, compared to the length-adjustable push rod described above, see fig. 7. The length-adjustable push rod 004 comprises a push rod 1101, two ends of the push rod 1101 are respectively provided with a connecting part 1102, and the connecting parts 1102 are provided with through holes 11021 for connecting adjacent push rods or supporting sheets. In order to improve the force bearing capacity of the connecting part 1102, a reinforcing rib 1103 is further provided, one end of the reinforcing rib 1103 is connected with the connecting part 1102, and the other end is fixed on the surface of the post rod 1101.

In some embodiments, the push rod 1101 can be implemented by a steel pipe. A metal tube of aluminum alloy material may also be employed.

Referring to fig. 8, in one embodiment, a slot 1104 may be further formed at one end of the length-fixing mandril, the slot 1104 is a through slot, and the width of the slot 1104 is matched with the width of the rib tube of the supporting sheet, and can be set to be clearance fit. Thus, when the device is installed, the ejector rod is perpendicular to the support piece and tightly propped against the support piece through the groove; the ribbed tube of the strut described above can be inserted into the slot 1104 to secure the length-adjustable ram.

In some embodiments, the two ejector rods can be made of flat steel pipes with 50 gamma 100, the ejector rods can be connected through bolts, and the length of the ejector rod with the fixed length is set to be 0.5 meter, 0.7 meter and 1 meter.

The length of the first inner sleeve movable ejector rod 102 of the length-adjustable ejector rod when the first inner sleeve movable ejector rod 102 does not extend is set to be three specifications of 0.5 meter, 0.7 meter and 1 meter, and the length of the first inner sleeve movable ejector rod 102 after extending is set to be three specifications of 0.5+0.15 meter, 0.7+0.25 meter and 1+0.3 meter. And determining whether the ejector rods are installed or not and the installation quantity of the ejector rods according to the size and the length of the foundation pit. The mandril can be installed when the length of the base arm is more than 3 meters.

The foundation pit is rectangular, when the ejector rod assemblies are multiple, the ejector rod assemblies can be arranged in parallel and used for supporting two opposite sides of the foundation pit. Wherein, the distance between any two adjacent ejector rod assemblies can be set to be 1.5-2 meters. The distance between the side mandril assemblies respectively positioned at the two edges and the adjacent parallel support pieces is preferably set to be 1.5-2 meters.

In a fifth aspect, the present application provides a pit arm support, referring to fig. 9, comprising a plurality of sequential end-to-end buttresses; wherein, the supporting piece comprises a length adjustable supporting piece 001 and a length non-adjustable supporting piece 002; the crater arm assembly is a polygonal structure in which at least one adjustable length support 001 as described in any one of the above is provided on each side.

In some embodiments, the pit arm support is quadrilateral in shape, with at least one adjustable length leg 001 on each side.

The utility model provides an foretell hole arm support owing to set up at least one adjustable length brace 001 to can adjust the length of this adjustable length brace 001 according to the size of hole arm, thereby can guarantee the fastness of support, accomplish the support task. In the prior art, due to the fact that the size of the tunnel is not uniform in the scene of actual construction, a standard support is not used for protection, and accidents are very easy to happen when the tunnel is deep. And adopt the pit arm support of this application, the probability that can very big reduction occurence of failure improves job site's workman's security.

In some embodiments, the pit arm support is provided with a closed area, and the closed area is surrounded by the pit arm supports; the ejector rod component comprises a plurality of ejector rods which are sequentially connected end to end.

Preferably, the ejector rod assembly at least comprises one ejector rod with adjustable length.

Illustratively, as shown, the ram assembly includes one of the adjustable length rams 003 and fixed length rams 004 described above.

In some embodiments, a plurality of square tubes 005 and a connector 0051 are also included. A square tube 005 is arranged between any two adjacent edges of the pit arm component; two side vertical surfaces of the square tube 005 are respectively connected with one end of the adjacent support piece.

As shown in fig. 10, in some embodiments, a plurality of studs 0051 are respectively disposed on two adjacent side surfaces of the square pipe 005, and when connecting, the studs 0051 pass through the through holes of the connecting portions of the support pieces, and are fastened by nuts. The distance between any two adjacent studs may be set to be the same. As shown, there may be 4 studs on each side.

In some embodiments, the square tube 005 may be erected at a corner of a foundation pit, and a 100 x 100 square steel tube may be used, and the height may be set to 0.5 m.

The two supporting pieces are arranged between the square corner tubes, can be made of flat steel tubes of 50 gamma 100 and have the height of 0.5 m, and are connected by bolts; the length of the fixed supporting piece can be set to three specifications of 0.5 meter, 0.7 meter and 1 meter, the length of the first inner sleeve movable part 12 of the adjustable supporting piece can be set to three specifications of 0.5 meter, 0.7 meter and 1 meter when not extending out, and the length of the first inner sleeve movable part 12 after extending out is set to three specifications of 0.5+0.15 meter, 0.7+0.25 meter and 1+0.3 meter.

The following steps of installation are exemplified. The first step is installing the support, specifically, digging the foundation pit to 1 meter deep according to the design position, the plane size of design and pausing the excavation, clearing, flattening the pit bottom and pit arm, firmly connecting two square tubes of one side pit arm with the length-adjustable branch piece and the length-fixed branch piece by bolts at the pit bottom, and tightly attaching to the pit arm, wherein the positions of the length-adjustable branch piece and the length-fixed branch piece can be randomly placed.

When the length is adjusted, the reversing handle is pulled to the extending position, the non-return pawl is pulled out, the non-return pawl is separated from the non-return ratchet wheel, the hexagonal poking wheel on the length-adjustable supporting piece is pulled by a common wrench, so that the first inner sleeve movable part 12 extends out of the first outer sleeve fixing part 11, the length is increased, and the square angle pipe is tightly propped against the pit arm. The non-return pawl is put back to enable the non-return pawl to be closely attached to the non-return ratchet wheel so as to prevent the ratchet wheel from rotating; the supports of other pit arms are installed in the same way, and all the supporting pieces are ensured to be fully propped against the pit arms to prevent the supports from sliding downwards.

If the supporting column assembly needs to be installed, a length-adjustable supporting column is firmly connected with a plurality of length-fixed supporting columns, then one end, provided with a groove, of each supporting column is propped against a supporting sheet rib, when the length of the length-adjustable supporting column is adjusted, the reversing handle can be shifted to the extending position, the non-return pawl is pulled out, the non-return pawl is separated from the non-return ratchet wheel, the shifting wheel handle is pulled, the movable ejector rod of the first inner sleeve extends out, the length of the movable ejector rod is lengthened, the supporting column is tightly propped against the pit arm supporting sheet, the non-return pawl is placed back, and the non-return pawl is tightly attached to the non-return ratchet wheel so as to prevent the ratchet wheel from rotating.

Secondly, installing other supports, specifically, digging a foundation pit for 0.6 m downwards, and installing the supports by adopting the method; the operation is repeated in a circulating way until the protective bracket is not arranged when the bracket is arranged to be 0.6 to 1 meter away from the designed elevation of the pit bottom; and then, excavating the pit bottom to the designed elevation by adopting a manual method, and quickly constructing and masonry to the bottom of the support according to the design.

Thirdly, dismantling the bracket, specifically, suspending construction and designing masonry, dismantling the protective bracket arranged 1-2 steps above the masonry surface, and continuing construction and designing the masonry to the bottom of the bracket; and the steps are repeated in a circulating way until the protective support is completely removed, and the rest part of the foundation is constructed.

The support of this application comprises square tube, support piece, ejector pin. The support has the advantages that the components are light in weight, simple in structure, easy to manufacture, easy to operate on site and high in applicability, can be assembled and disassembled at the bottom of a pit by a single person without special tools, can be randomly customized and combined and randomly set in length and width according to actual conditions on site, and is flexible; the support can be self-supporting and does not fall down.

The foregoing is illustrative of the preferred embodiments of the present application and is not to be construed as limiting thereof, since numerous modifications and variations will readily occur to those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A length adjustable prop, comprising: the first outer sleeve fixed ejector rod and the first inner sleeve movable ejector rod;

the first outer sleeve fixing ejector rod is of a hollow structure; the first end is provided with a connecting part which is used for connecting the support piece or the strut;

2. The length adjustable strut as claimed in claim 1, wherein the first outer sleeve fixed post rod and the first inner sleeve movable post rod are provided with a plurality of through holes opposite to each other, and are connected by a connecting member.

3. The length adjustable strut of claim 1, further comprising a second transmission mechanism, the second transmission mechanism comprising: a second ratchet mechanism and a force transmission rack;

4. A length adjustable prop according to claim 3, further comprising: the handle comprises a handle, two handle ears are arranged at one end of the handle, the two handle ears are arranged oppositely, and a bidirectional ratchet wheel is arranged in each handle ear;

5. A length adjustable prop according to claim 4, wherein the handle is adjustable in length.

6. The length adjustable strut of claim 1, wherein the first end of the first outer sleeve fixing ejector rod is provided with a groove, the width of the groove is matched with the width of a rib tube of the strut for being inserted on the rib tube to fix the length adjustable strut.

7. The length-adjustable prop according to claim 1, wherein the connecting portion is provided with a through hole, and the connection is performed by using a bolt.

8. The length-adjustable prop according to any one of claims 1 to 7, wherein the material of the first outer sleeve fixed top rod and the first inner sleeve movable top rod is aluminum alloy.