CN205419602U - Modular cantilever crane - Google Patents

Abstract

The utility model relates to a hoisting equipment technical field, in particular to modular cantilever crane. The utility model provides a modular cantilever crane, including base member cantilever crane, extension cantilever crane and cantilever crane connecting device, wherein, the extension cantilever crane passes through cantilever crane connecting device detachably and connects on at least one side of base member cantilever crane. The utility model discloses change the welding arm frame of integral type into detachable modular cantilever crane, the design of messenger's cantilever crane no longer receives the restriction of factors such as transportation clearance, hauled weight, and the bearing capacity of cantilever crane can improve at double to can satisfy the requirement of extra -large -size hoisting equipment to cantilever crane bearing capacity.

Description

A kind of combination type jib

Technical field

This utility model relates to technical field of crane equipment, particularly to a kind of combination type jib.

Background technology

The fast development built along with international energy and chemical engineering, in engineering construction, modularity, maximization and integration lifting requirements improve constantly, and lifting capacity and hoisting moment to crane gear are had higher requirement.Boom system directly affects serviceability and the lifting performance of complete machine as the main bearing member of crane gear, the characteristic such as the version of himself, bearing capacity.

Say in terms of stress, jib belongs to bi-axial bending moment, when i.e. crane gear hangs load work, jib all bears the effect of axial force and moment of flexure in luffing plane and plane of rotation, luffing plane refers to plane determined by jib and luffing arm-tie, in luffing plane, jib is analyzed as the mechanical model of two ends freely-supported；Plane of rotation refers to parallel ground and the plane vertical with luffing plane, and in plane of rotation, jib is fixed one end mechanical model freely as one end and is analyzed.Therefore, from telescopic boom section analysis, need enough sectional areas, to ensure telescopic boom section intensity, thus resist the effect of axial force, and need enough cross-sectional widths and highly with the moment of inertia in two planes of guarantee, thus improve unbending.Visible, in order to improve the bearing capacity of jib, need to increase specification and the sectional dimension of jib of main chord 1 '.

But, increase telescopic boom section size and make jib and meet transportation clearance to require it is the problem of conflict, and how solving this problem and have become as the crucial technology barrier that crane gear develops to ultra-large type.As shown in Figure 1-2, in the prior art, the jib of crane gear generally uses the truss structure by four main chords 1 ' and the welding of some web members 2 ', in length L side, connected mode upwardly through joint and bearing pin can realize the connection between jib for it, but it is parallel to two sides of luffing plane (the depth of section direction in Fig. 2) and two sides (cross-sectional width direction in Fig. 2) vertical with becoming spoke plane (after jib is installed on crane gear) and is single layer structure, owing to existing jib is integrated Welding Structure, the sectional dimension (cross-sectional width B and depth of section H) increasing jib then means to increase the transportation clearance of jib, increase the weight of jib, cause transport inconvenience.Visible, by transportation clearance and transport heavy quantitative limitation, the jib structure of existing integrally molded form can not meet the requirement to jib bearing capacity of the ultra-large type crane gear.

Utility model content

One to be solved in the utility model technical problem is that: existing jib is integrated welded structure, and by transportation clearance and transport heavy quantitative limitation, it can not meet the requirement to jib bearing capacity of the ultra-large type crane gear.

In order to solve above-mentioned technical problem, this utility model provides a kind of combination type jib, and it includes that matrix jib, extension jib and arm support connection device, extension jib are removably attachable at least one side of matrix jib by arm support connection device.

Alternatively, arm support connection device includes the first connecting portion, the second connecting portion and connector, and the first connecting portion is connected on matrix jib, and the second connecting portion is connected to extend on jib, and the first connecting portion and the second connecting portion are removably connected by connector.

Alternatively, the first connecting portion is slot, and the second connecting portion is the plate being inserted in slot, and connector is to be correspondingly provided with pin-and-hole on the first bearing pin, slot and plate, and the first bearing pin can realize removably connecting of slot and plate through pin-and-hole.

Alternatively, the first connecting portion is sleeve, and the second connecting portion is the sleeve pipe being inserted in sleeve, and connector is to be correspondingly provided with pin-and-hole on the second bearing pin, sleeve and sleeve pipe, and the second bearing pin can realize removably connecting of sleeve and sleeve pipe through pin-and-hole.

Alternatively, arm support connection device includes that envelope part and locking piece, envelope part have peristome with by the main chord envelope of the main chord of matrix jib and extension jib wherein, and locking piece is for closing the peristome of envelope part.

Alternatively, the first end of locking piece is rotatably connected at the first side of the peristome of envelope part, and the second end of locking piece removably connects with the second side of the peristome of envelope part.

Alternatively, the first end of locking piece is rotatably connected at first side of peristome of envelope part by the 3rd bearing pin or bolt.

Alternatively, the second end of locking piece is provided with installing hole, in the second side of the peristome of envelope part is inserted into installing hole and is locked by securing member.

Alternatively, the side of the peristome of the close envelope part of locking piece is provided with bracket, and when the peristome of envelope part is closed by locking piece, the main chord of matrix jib or the main chord of extension jib contact with bracket.

Alternatively, the main chord of matrix jib contacts with bracket, and the surface that the main chord with matrix jib of bracket contacts has the shape adapted with matrix jib；Or, the main chord of extension jib contacts with bracket, and the surface that the main chord with extension jib of bracket contacts has the shape that the main chord with extension jib adapts.

Alternatively, arm support connection device also includes cushion block, cushion block be arranged on matrix jib main chord and extension jib main chord between so that matrix jib and extension jib between from a distance.

Alternatively, cushion block has the first surface that the main chord with extension jib adapts；And/or, cushion block has the second surface that the main chord with matrix jib adapts.

Alternatively, it is characterised in that envelope part is U-shaped frame.

Combination type jib provided by the utility model, it uses arm support connection device matrix jib and extension jib to be removably connected, change the welding jib of integral type into dismountable combination type jib, the design making jib is no longer limited by the factor such as transportation clearance, hauled weight, the bearing capacity of jib can significantly improve such that it is able to meets the requirement to jib bearing capacity of the ultra-large type crane gear.

By being described in detail exemplary embodiment of the present utility model referring to the drawings, further feature of the present utility model and advantage thereof will be made apparent from.

Accompanying drawing explanation

In order to be illustrated more clearly that this utility model embodiment or technical scheme of the prior art, the accompanying drawing used required in embodiment or description of the prior art will be briefly described below, apparently, accompanying drawing in describing below is only embodiments more of the present utility model, for those of ordinary skill in the art, on the premise of not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 illustrates the front view of jib structure of the prior art.

Fig. 2 illustrates the sectional view of jib structure of the prior art.

Fig. 3 illustrates the front view of the combination type jib of this utility model first embodiment.

Fig. 4 illustrates the axonometric chart of the matrix jib of embodiment illustrated in fig. 3.

Fig. 5 illustrates the front view of the matrix jib of embodiment illustrated in fig. 3.

Fig. 6 illustrates the axonometric chart of the extension jib of embodiment illustrated in fig. 3.

Fig. 7 illustrates the front view of the extension jib of embodiment illustrated in fig. 3.

Fig. 8 illustrates the front view of the combination type jib of this utility model the second embodiment.

Fig. 9 illustrates the front view of the matrix jib of embodiment illustrated in fig. 8.

Figure 10 illustrates the front view of the extension jib of embodiment illustrated in fig. 8.

Figure 11 illustrates the axonometric chart of the sleeve of embodiment illustrated in fig. 8.

Figure 12 illustrates the axonometric chart of the sleeve pipe of embodiment illustrated in fig. 8.

Figure 13 illustrates the front view of the combination type jib of this utility model the 3rd embodiment.

Figure 14 illustrates structural representation when the U-shaped frame of embodiment illustrated in fig. 13 is in closed state.

Figure 15 illustrates structural representation when the U-shaped frame of embodiment illustrated in fig. 13 is in open mode.

Figure 16 illustrates the structural representation of the cushion block of embodiment illustrated in fig. 13.

In figure:

1 ', main chord；2 ', web member；

1, matrix jib；2, extension jib；31, slot；32, plate；33, the first bearing pin；41, sleeve；42, sleeve pipe；43, the second bearing pin；51, U-shaped frame；52, locking piece；521, bracket；53, the 3rd bearing pin；54, nut；55, cushion block.

Detailed description of the invention

Below in conjunction with the accompanying drawing in this utility model embodiment, the technical scheme in this utility model embodiment is clearly and completely described, it is clear that described embodiment is only a part of embodiment of this utility model rather than whole embodiments.Description only actually at least one exemplary embodiment is illustrative below, never as to this utility model and application thereof or any restriction of use.Based on the embodiment in this utility model, the every other embodiment that those of ordinary skill in the art are obtained under not carrying out creative work premise, broadly fall into the scope of this utility model protection.

May be not discussed in detail for technology, method and apparatus known to person of ordinary skill in the relevant, but in the appropriate case, described technology, method and apparatus should be considered to authorize a part for description.

In description of the present utility model, it will be appreciated that, the noun of locality is as " front, after, on, under, left, right ", " laterally, vertically, vertically, level " and " top, the end " etc. indicated orientation or position relationship be normally based on orientation shown in the drawings or position relationship, it is for only for ease of description this utility model and simplifies description, in the case of illustrating on the contrary, these nouns of locality do not indicate that and imply that the device of indication or element must have specific orientation or with specific azimuth configuration and operation, therefore it is not intended that restriction to this utility model protection domain；The noun of locality " inside and outside " refers to inside and outside the profile relative to each parts itself.

In description of the present utility model; it will be appreciated that; the word such as " first ", " second " is used to limit parts; it is intended merely to facilitate and corresponding parts are distinguished; as there is no Stated otherwise; above-mentioned word does not has particular meaning, therefore it is not intended that restriction to this utility model protection domain.

Fig. 3-16 shows three embodiments of the present utility model.With reference to Fig. 3-16, combination type jib provided by the utility model, including matrix jib 1, extension jib 2 and arm support connection device, wherein, extension jib 2 by arm support connection device along at least one side being removably attachable to matrix jib 1.

Combination type jib provided by the utility model, the welding mentality of designing that it breaks traditions, use arm support connection device that with extending jib 2 at least one side along matrix jib 1, matrix jib 1 is carried out detachable connection, change the welding jib of integral type into dismountable combination type jib, enable the sectional dimension of jib no longer by transportation clearance, the restriction of the factors such as hauled weight, such that it is able to effectively solve the problem that jib bearing capacity limits this conflict with jib transportation clearance, the bearing capacity of jib is greatly improved, basis is provided to ultra-large type development for crane gear.In addition, dismountable combination type jib can assemble the boom system forming bearing capacity the most of the same race according to reality lifting demand and lifting condition, on the one hand disclosure satisfy that the demand of different operating mode, apply more flexible, on the other hand the bearing capacity of jib self can also be made to reach good mating with the overall performance of crane gear so that the performance of overall performance and jib self is more efficiently utilized.And, jib to be strengthened mode and is changed into assembled by welding type, the processing technique also making jib is simpler, and the improvement of jib performance is more prone to realize such that it is able to effectively reduce the production cost of jib.

Three embodiments of the present utility model are all as a example by rectangular combination type jib by cross sectional shape, and all by extension jib 2 be connected to two the relative sides (i.e. side corresponding to cross-sectional width) being perpendicular to become spoke plane of matrix jib 1 upper as a example by this utility model is illustrated.In other embodiments, extend on the side that jib can also be connected only to be perpendicular to become in two relative sides of spoke plane；Or, it is also connected to be parallel on two relative sides (i.e. side corresponding to depth of section) of change spoke plane in cross sectional shape is rectangular combination type jib；Each on each side in all of four sides an extension jib can also be connected in cross sectional shape is rectangular combination type jib.Certainly, this utility model is equally applicable to the combination type jib of other cross sectional shape, such as the combination type jib of trapezoid cross section.

Additionally, in three embodiments of this utility model, matrix jib 1 is integrated welding type space truss structure, extension jib 2 is the plane girder group structure of integral type, but in other embodiments, matrix jib can also be knockdown space truss shelf structure, and extension jib 2 can also be knockdown truss structural, or be integrated welding type or knockdown space truss structure.

Arm support connection device of the present utility model has numerous embodiments, illustrates below as a example by two kinds of embodiments.

The first embodiment as this utility model arm support connection device, arm support connection device can include the first connecting portion, the second connecting portion and connector, first connecting portion is connected on matrix jib 1, second connecting portion is connected to extend on jib 2, and the first connecting portion and the second connecting portion are removably connected by connector.So connected fixing to the first connecting portion and the second connecting portion by connector, i.e. extension jib 2 can be assembled on matrix jib 1, increase the sectional dimension of jib, strengthen the bearing capacity of jib, and when needs transport, matrix jib 1 and extension jib 2 can be made to transport as two single parts by removing connector again, meet the requirement of transportation clearance such that it is able to effectively solve the problem that jib bearing capacity limits this conflict with jib transportation clearance.

Arm support connection device based on this first embodiment, this utility model provides the first embodiment of the combination type jib as shown in Fig. 3-Fig. 7 and the second embodiment of combination type jib as illustrated in figs. 8-12.

From Fig. 3-7, in first embodiment of the present utility model, combination type jib includes matrix jib 1, extension jib 2 and arm support connection device, wherein, arm support connection device includes as the first connecting portion, second connecting portion and connector, first connecting portion is the slot 31 being connected on matrix jib 1, second connecting portion is to be correspondingly connected to extend the plate 32 on jib 2, connector is the first bearing pin 33, plate 32 is inserted in slot 31, and it is correspondingly provided with pin-and-hole on slot 31 and plate 32, first bearing pin 33 can realize removably connecting of slot 31 and plate 32 through pin-and-hole, thus realize matrix jib 1 and be connected with extension the detachable of jib 2.

Based on this embodiment, when needing the bearing capacity increasing jib, plate 32 is inserted in the slot 31 of correspondence, and by the first bearing pin 33, matrix jib 1 and extension jib 2 are fixed together, increase the cross-sectional width B (or depth of section H) of matrix jib 1, so that combination type jib has higher bending resistance and Anti-pull-press ability；And when needs transport, then the first bearing pin 33 can be disconnected, conveniently realize matrix jib 1 and the dismounting of extension jib 2, such that it is able to matrix jib 1 and extension jib 2 are transported as two single parts, to reduce jib shipping height (or reducing jib conveyor width), alleviate jib hauled weight, meet jib transportation clearance requirement.Visible, in this embodiment, matrix jib 1 and extension jib 2 use board plug type connected mode to form combination type jib, the sectional dimension making jib need not be limited by the factor such as transportation clearance, hauled weight again, such that it is able to the bearing capacity of jib is greatly improved, can meet the demand of different actual condition neatly, cost is relatively low, and technique is simpler.

As shown in Figure 4, in this embodiment, slot 31 is connected on the main chord of matrix jib 1 be formed by two plates being parallel to each other, namely this slot 31 is double plate slots, accordingly, as shown in Figure 6, in this embodiment, plate 32 is the single board plug structure being connected to extend the corresponding position on the main chord of jib 2, and the width of this plate 32 is less than the spacing between double plates of slot 31, to ensure that plate 32 can insert in slot 31 smoothly.Certainly, the board plug type connected mode between this utility model matrix jib 1 and extension jib 2 is not limited to this veneer version to double plates, and it can also use double plate to other versions such as three plates.Additionally, as shown in Figure 4, in this embodiment, slot 31 is the depth of section H direction setting along matrix jib 1, but it practice, slot 31 can also be arranged along the cross-sectional width B direction of matrix jib 1, these are all within protection domain of the present utility model.

From Fig. 8-12, in the second embodiment of the present utility model, matrix jib 1 and extension jib 2 use telescopic connected mode to form combination type jib, it is with the difference of first embodiment, first connecting portion of arm support connection device is the sleeve 41 being connected on matrix jib 1, second connecting portion of arm support connection device is to be connected to extend the sleeve pipe 42 on jib 1, the connector of arm support connection device is the second bearing pin 43, wherein, the external diameter of sleeve pipe 42 is less than the internal diameter of sleeve 41, thus sleeve pipe 42 can insert in sleeve 41 smoothly, and it is correspondingly provided with, on sleeve 41 and sleeve pipe 42, the pin-and-hole passed for the second bearing pin 43.

As shown in Figure 8, sleeve pipe 42 is inserted in sleeve 41, and make the second bearing pin 43 through pin-and-hole, then can realize matrix jib 1 and extend the assembling of jib 2, and as shown in figs. 9-10, second bearing pin 43 is disconnected, then can realize matrix jib 1 and the separation of extension jib 2, thus make the combination type jib of this embodiment can not only increase the sectional dimension of jib easily, strengthen the bearing capacity of jib, and transportation clearance can be met and limit, transport easily.

As shown in FIG. 11 and 12, in this second embodiment, sleeve 41 and sleeve pipe 42 use hollow circular tube structure, it practice, use square tube, rectangular tube or the sleeve 41 of other shape tube structures and sleeve pipe 42 also to be able to realize the purpose of this utility model.

The second embodiment as this utility model arm support connection device, arm support connection device can include envelope part and locking piece 52, wherein, envelope part has peristome with by the main chord envelope of matrix jib 1 and extension jib 2 wherein, locking piece 52 is then for closing the peristome of envelope part, so coordinating by envelope part and locking piece 52, then it is capable of matrix jib 1 and extends removably connecting of jib 2.

Locking piece 52 can be the separate part separated with envelope part, and such as it can be a bearing pin, and this bearing pin can realize the closing to envelope part peristome through the pin-and-hole of envelope part peristome both sides.But the unnecessary trouble caused for the reason such as parts easily loss reduced because separating, locking piece 52 and envelope part can be designed as movable connection structure, such as, first end of locking piece 52 is rotatably connected at the first side of the peristome of envelope part, second end of locking piece 52 removably connects with the second side of the peristome of envelope part, so can not only conveniently realize opening and closing of envelope part peristome, i.e. conveniently realize matrix jib 1 and the assembly and disassembly of extension jib 2, and owing to the first end of locking piece 52 links together with envelope part all the time, therefore can also prevent parts from losing, use more convenient.

Arm support connection device based on this second embodiment, this utility model provides the 3rd embodiment of combination type jib as shown in figures 13-16.

From Figure 13-16, in the 3rd embodiment, matrix jib 1 and extension jib 2 use U-shaped frame connected mode to form combination type jib.As shown in FIG. 14 and 15, in this embodiment, envelope part is U-shaped frame 51, and it has peristome, first side of this peristome is rotatably connected by the first end of the 3rd bearing pin 53 with locking piece 52, and the second end of locking piece 52 is then provided with the installing hole that the second side with this peristome adapts.So, as shown in figure 14, make the second side of U-shaped frame 51 peristome insert in the installing hole of locking piece 52 second end, and locked by nut 54 or other securing members, i.e. the peristome of U-shaped frame 51 can be closed；And as shown in figure 15, loosening nut 54 securing member such as grade, and rotate locking piece 52 around the 3rd bearing pin 53, it becomes possible to the peristome of U-shaped frame 51 is opened.Certainly, the 3rd bearing pin 53 can also replace with other structural members such as bolts.

Combination type jib based on this embodiment, as shown in figure 13, U-shaped frame 51 is enclosed within the main chord of matrix jib 1 and the main chord of extension jib 2, and by the securing member such as locking piece 52 and nut 54, the peristome of U-shaped frame 51 is closed, just extension jib 2 can be assembled on matrix jib 1, so that combination type jib has bigger sectional dimension, and then combination type jib is made to have higher bending resistance and Anti-pull-press intensity；And when needs transport, the most only need loosening nut 54 securing member such as grade and rotate locking piece 52, the peristome of U-shaped frame 51 is opened, it becomes possible to make matrix jib 1 and extension jib 2 separate, transport as two single parts, meet the restriction of transportation clearance.

In addition, from Figure 14 and Figure 15, in the 3rd embodiment, the side of the peristome of the close envelope part of locking piece 52 is provided with bracket 521, this bracket 521 is for contacting with the main chord of matrix jib 1 when being fitted together with extension jib 2 by matrix jib 1, form the support of the main chord to matrix jib 1, increase the steadiness assembled, and improve the force-bearing situation of jib further.And, in order to preferably form support, in this embodiment, the surface that the main chord with matrix jib 1 of this bracket 521 contacts has the arcuate shape that the main chord with matrix jib 1 adapts.

It should be noted that, in this embodiment, bracket 521 is that the main chord with matrix jib 1 contacts, but those skilled in the art are understood that, bracket 521 actually can also contact with the main chord of extension jib 2, now the main chord of extension jib 2 is formed and supports by bracket 521, and bracket 521 can have the curved surfaces that the main chord with extension jib 2 adapts.

Further, as shown in figure 13, in the 3rd embodiment, arm support connection device also includes cushion block 55, this cushion block 55 be arranged on matrix jib 1 main chord and extension jib 2 main chord between so that matrix jib 1 and extension jib 2 between from a distance, so can not only avoid the direct rigid contact between matrix jib 1 and extension jib 2, but also ensure that effective transmission of power between matrix jib 1 and extension jib 2.

Arranging more reliably to realize cushion block 55, cushion block 55 can have the surface configuration that the main chord of the main chord with matrix jib 1 and/or extension jib 2 adapts.As shown in figure 16, in the 3rd embodiment, cushion block 55 has the first curved surfaces that the main chord with extension jib 2 adapts, and the second curved surfaces adapted with the main chord of matrix jib 1, so cushion block 55 more effectively can contact, so that the structure of combination type jib is relatively reliable with matrix jib 1 and extension jib 2.

Visible, combination type jib of the present utility model is changed into assembled by jib is strengthened mode by welding type, the design making jib need not be again by transportation clearance and transport heavy quantitative limitation, the bearing capacity of jib can be greatly improved, can unconfined promote in theory, so that crane gear develops into possibility to large.

The foregoing is only exemplary embodiment of the present utility model, not in order to limit this utility model, all within spirit of the present utility model and principle, any modification, equivalent substitution and improvement etc. made, within should be included in protection domain of the present utility model.

Claims (11)

1. a combination type jib, it is characterized in that, including matrix jib (1), extension jib (2) and arm support connection device, described extension jib (2) is removably attachable at least one side of described matrix jib (1) by described arm support connection device；Described arm support connection device includes the first connecting portion, the second connecting portion and connector, described first connecting portion is connected on described matrix jib (1), described second connecting portion is connected on described extension jib (2), and described first connecting portion and described second connecting portion are removably connected by described connector；Or, described arm support connection device includes envelope part and locking piece (52), described envelope part has peristome with by the main chord envelope of the main chord of described matrix jib (1) and described extension jib (2) wherein, and described locking piece (52) is for closing the peristome of described envelope part.

Combination type jib the most according to claim 1, it is characterized in that, described first connecting portion is slot (31), described second connecting portion is the plate (32) being inserted in described slot (31), described connector is the first bearing pin (33), being correspondingly provided with pin-and-hole on described slot (31) and described plate (32), described first bearing pin (33) can realize removably connecting of described slot (31) and described plate (32) through described pin-and-hole.

Combination type jib the most according to claim 1, it is characterized in that, described first connecting portion is sleeve (41), described second connecting portion is the sleeve pipe (42) being inserted in described sleeve (41), described connector is the second bearing pin (43), being correspondingly provided with pin-and-hole on described sleeve (41) and described sleeve pipe (42), described second bearing pin (43) can realize removably connecting of described sleeve (41) and described sleeve pipe (42) through described pin-and-hole.

Combination type jib the most according to claim 1, it is characterized in that, first end of described locking piece (52) is rotatably connected at the first side of the peristome of described envelope part, and the second end of described locking piece (52) removably connects with the second side of the peristome of described envelope part.

Combination type jib the most according to claim 4, it is characterised in that the first end of described locking piece (52) is rotatably connected at the first side of the peristome of described envelope part by the 3rd bearing pin (53) or bolt.

Combination type jib the most according to claim 4, it is characterised in that the second end of described locking piece (52) is provided with installing hole, in the second side of the peristome of described envelope part is inserted into described installing hole and is locked by securing member.

Combination type jib the most according to claim 1, it is characterized in that, the side of the peristome of the close described envelope part of described locking piece (52) is provided with bracket (521), when the peristome of described envelope part is closed by described locking piece (52), the main chord of described matrix jib (1) or the main chord of described extension jib (2) contact with described bracket (521).

Combination type jib the most according to claim 7, it is characterized in that, the main chord of described matrix jib (1) contacts with described bracket (521), and the surface that the main chord with described matrix jib (1) of described bracket (521) contacts has the shape adapted with described matrix jib (1)；Or, the main chord of described extension jib (2) contacts with described bracket (521), and the surface that the main chord with described extension jib (2) of described bracket (521) contacts has the shape that the main chord with described extension jib (2) adapts.

Combination type jib the most according to claim 1, it is characterized in that, described arm support connection device also includes that cushion block (55), described cushion block (55) are arranged between main chord and the main chord of described extension jib (2) of described matrix jib (1) so that between described matrix jib (1) and described extension jib (2) from a distance.

Combination type jib the most according to claim 9, it is characterised in that described cushion block (55) has the first surface that the main chord with described extension jib (2) adapts；And/or, described cushion block (55) has the second surface that the main chord with described matrix jib (1) adapts.

11. according to the arbitrary described combination type jib of claim 1-10, it is characterised in that described envelope part is U-shaped frame (51).