WO2019109911A1

WO2019109911A1 - Small crane having adjustable boom structure

Info

Publication number: WO2019109911A1
Application number: PCT/CN2018/119192
Authority: WO
Inventors: 陈根平
Original assignee: 陈根平
Priority date: 2017-12-05
Filing date: 2018-12-04
Publication date: 2019-06-13
Also published as: CN107826992A; CN107826992B

Abstract

Disclosed is a small crane having an adjustable boom structure, the crane comprising a main machine (3), an upright assembly, a boom assembly and a frame adjusting assembly (11). The crane structure is stable and has strong adaptability, can perform structural transformation for remote hoisting, mid-range hoisting and near hoisting according to the actual scenario of a construction window, solving the problem traditionally of the structure of adjustable small cranes being unable to completely adapt to various hoisting environments.

Description

Small crane with adjustable boom structure

Technical field

The invention relates to the field of lifting machinery, in particular to a small crane with an adjustable boom structure.

Background technique

In the prior art, the document No. 201410039462.4 discloses an adjustable small crane comprising a main body, a pole assembly and an arm assembly, the size of the pole assembly and the arm assembly being adjustable as needed. The utility model can be widely applied to high-rise indoor decoration lifting materials. However, due to the fluidity of the decoration personnel and the corresponding installation conditions of different construction sites, the adjustable small crane has a lot of space for improvement in actual operation. In order to hoist the different situations of different windows, the traditional single structure style adjustable small crane has certain limitations, which can not fully meet the needs of various lifting environments.

technical problem

The small crane in the prior art has a single structure, and has certain limitations for lifting different windows and different conditions, and cannot fully meet the requirements of various lifting environments.

Technical solution

The invention adds the adjusting frame assembly on the basis of the existing adjustable small crane, and improves the arm assembly, and can realize various changing structures, so that the adjustable boom crane can be turned and folded. It can be straight and retractable, fully satisfying the hoisting requirements of adapting to different types of window hoisting environments, and improving the universal adaptability of adjustable small cranes.

To this end, the specific scheme of the present invention is as follows:

A small crane with an adjustable boom structure, comprising a main body, a pole assembly and an arm assembly, the main body comprising a main base and a motor main body and a pole sleeve disposed on the main base; the pole assembly The utility model comprises a vertical rod, a top hat fixed on the upper end of the vertical pole, a rotating arm sleeve which is set on the vertical pole and supported by the hoop, a jack screw which is set in the lower end of the vertical rod and is set on the jack screw for supporting the pole Screw nut, the jack screw is set in the pole sleeve;

The utility model further comprises an adjustment frame assembly, wherein the adjustment frame assembly is a frame structure composed of an upper arm, a lower arm, an upper sleeve, a lower sleeve and a vertical arm, wherein the upper arm and the lower arm are fixed horizontally a rod and an adjustable cross rod, the fixed cross rod is horizontally fixed on the arm sleeve, and the fixed cross rod is provided with at least one first cross rod mounting hole, and one end of the adjustable cross rod is provided with at least one a second crossbar mounting hole, the other end of the adjustable crossbar is provided with a first swivel sleeve connecting hole; the first crossbar mounting hole of the fixed crossbar is matched with the second crossbar mounting hole of the adjustable crossbar The upper rotating sleeve and the lower rotating sleeve respectively comprise a sleeve and a connecting plate fixed on one side of the sleeve, wherein the connecting plate is provided with a second rotating sleeve connecting hole, and the first rotating arm is first The sleeve connecting hole and the second sleeve connecting hole of the upper sleeve are connected by bolts, and the first sleeve connecting hole of the lower arm and the second sleeve connecting hole of the lower sleeve are connected by bolts; the vertical arm includes a vertical rod, and a head pulley fixed to the top end of the vertical rod; the upper and lower ends of the vertical rod are respectively connected to the upper rotating sleeve Under transfer kit;

The arm assembly includes an outer arm tube connected to the lower connecting sleeve through a pin shaft, and an inner arm rod that is sleeved in the outer arm tube and has an adjustable length; the inner arm rod is composed of an upper arm rod and a lower arm rod. The end of the upper arm is provided with a recess, and the end of the lower arm is provided with a convex portion, and the concave portion cooperates with the convex portion and is connected by at least one bolt, when the upper arm and the lower arm are connected by only one bolt The angle between the upper arm and the lower arm can be adjusted within a range of 90°-180°; the upper arm and the upper connecting sleeve are connected by a basket screw, and the front end of the upper arm is mounted with a pulley hook assembly, the rotating arm A pole pulley is mounted on the sleeve, and the wire rope of the motor main body is sequentially connected through a pole pulley, a head pulley and a pulley hook assembly.

Further, the fixed cross bar is a channel steel, the adjustable cross bar is a rectangular steel pipe, one end of the fixed cross bar is welded on the arm sleeve, and the other end of the fixed cross bar is a concave crescent joint; The connecting end of the adjusting bar and the fixed cross bar adopts a rounded transition, and the other end of the adjustable cross bar is also a concave crescent joint, the curved radius of the concave crescent joint and the upper rotating sleeve or the lower rotating sleeve The circumference of the sleeve matches.

Further, the vertical rod is composed of an upper rod, a middle rod and a lower rod, wherein the middle rod is respectively screwed to the upper rod and the lower rod, and the upper rod is internally fixed by a screw with a telescopic inner rod, the telescopic inner rod The upper end and the head pulley are coupled by a nut and a screw.

Further, the upper side of the connecting plate of the lower rotating sleeve is mounted with a turning lever through a rotating shaft, and a side of the lower connecting sleeve adjacent to the turning control rod is provided with a concave groove, and when the turning lever is engaged with the concave shape When the slot is locked, the vertical arm is locked, and when the control lever is separated from the concave slot, the vertical arm can rotate.

Further, the second sleeve connecting holes of the upper sleeve and the lower sleeve are located at the center of the connecting plate, and the connecting plate is further provided with an auxiliary connecting hole away from the oblique lower corner of the sleeve.

Further, when the upper arm and the lower arm are at an angle of less than 180°, the upper arm is bolted with an upper pulley for transitioning the wire rope to the pulley hook assembly, and the upper arm and the lower arm pass A bent arm support rod is coupled to the bolt, the curved arm support rod includes an intermediate screw, and a bent arm sleeve threadedly coupled to both ends of the intermediate screw.

Further, the head pulley includes a pulley bracket, two lower pulleys fixed under the pulley bracket, two middle pulleys fixed in the middle of the pulley bracket, and one upper pulley fixed above the pulley bracket, the upper pulley and two The sides of the middle pulley and the two lower pulleys are arranged in a positive cross, and the wire rope is connected to the pulley hook assembly after passing through any of the pulleys through the center of the cross.

Further, the recess is screwed to the end of the upper arm, the convex portion is screwed to the end of the lower arm, and the concave portion and the convex portion are matched and connected by at least one bolt to be a separate concave-convex connecting member. After the embossed connector is detached, the upper arm and the lower arm are threadedly butted.

Further, the upper part of the vertical rod is provided with an upper connecting sleeve, and the lower part of the vertical rod is provided with a lower connecting sleeve, and the upper connecting sleeve and the lower connecting sleeve are respectively located above the upper rotating sleeve and the lower rotating sleeve, and the upward rotation The sleeve is connected to the upper sleeve by a first planar bearing, and the lower sleeve and the lower sleeve are connected by a second planar bearing.

Beneficial effect

The invention adds the adjusting frame assembly as a connecting member between the arm assembly and the pole assembly on the basis of the existing adjustable small crane, and the adjusting frame is composed of three turning arms and upper and lower connecting sleeves, which can be The construction environment can be freely combined and disassembled. When the vertical arm is retained, the bending of the boom can be realized without the pole sleeve moving. The arm assembly is optimized on the basis of the original inner and outer double poles, and the inner rod part design will be optimized. The inner rod is divided into upper and lower arm rods, and the upper and lower arm rods are connected by a concave-convex structure, and are fixed by bolts. When the single bolt is fixed, the hinge structure can be adjusted in the range of 90°-180° to adjust the bending of the inner rod. The degree of folding, while being fixed by more than two bolts, is the same as that of the conventional straight rod, and realizes the foldable and straightforward function of the arm, which can fully satisfy the window installation of different sizes; the structure of the invention is stable and has a comparative Strong adaptability, according to the actual situation of the construction window, the structural deformation under long distance hoisting, medium distance hoisting and close hoisting can solve the structure of the traditional adjustable small crane Full lifting of various environmental adaptation, truly a multi-purpose machine, small crane for the development of the industry made a significant contribution.

DRAWINGS

Figure 1 is a schematic view of the structure of the present invention;

2 is a schematic structural view of an adjustment frame assembly;

Figure 3 is a schematic structural view of an upper arm and a lower arm;

Figure 4 is a front view of the fixed crossbar;

Figure 5 is a side view of the fixed crossbar;

Figure 6 is a plan view of the fixed crossbar;

Figure 7 is a front view of the adjustable crossbar;

Figure 8 is a side view of the adjustable crossbar;

Figure 9 is a plan view of the adjustable crossbar;

Figure 10 is a schematic structural view of a vertical rod;

Figure 11 is a schematic structural view of an arm assembly;

Figure 12 is a front elevational view showing the first embodiment of the inner arm;

Figure 13 is a plan view of the first embodiment of the inner arm;

Figure 14 is an exploded view of the second embodiment of the inner arm;

Figure 15 is a combination view of Embodiment 2 of the inner arm;

Figure 16 is a variation diagram 1 of the second embodiment of the inner arm;

Figure 17 is a second variation of the second embodiment of the inner arm;

Figure 18 is a combination view of Embodiment 3 of the inner arm;

Figure 19 is a schematic structural view of an arm support rod;

Figure 20 is a front elevational view of the head pulley;

Figure 21 is a side view of the head pulley;

Figure 22 is a schematic structural view of an upper sleeve and a lower sleeve;

Figure 23 is a schematic structural view of a concave groove;

24 to 38 are structural diagrams of the transformation state of the present invention for different construction environments.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring to Figure 1, a small crane having an adjustable boom structure includes a main body, a pole assembly, and an arm assembly.

The main body part refers to the existing adjustable small crane structure, including the main base 1 and the motor main body 3 and the pole sleeve 2 disposed on the main base 1; the pole assembly includes a pole 4 fixed to the upper end of the pole 4 The top hat 5 is set on the pole 4 and supports the fixed arm sleeve 6 through the hoop 7, the jack screw 8 which is set in the lower end of the pole 4 and the jack 8 which is set on the jack 8 for supporting the pole 4. A screw nut 9 is placed in the pole sleeve 2 .

The present invention also includes an adjustment frame assembly 11, which is shown in Fig. 2, the adjustment frame assembly 11 being a frame consisting of an upper arm 18, a lower arm 19, an upper sleeve 20, a lower sleeve 21 and a vertical arm 22 structure.

Referring to FIGS. 3-9, the upper arm 18 and the lower arm 19 have the same structure, and are composed of a fixed crossbar 29 and an adjustable crossbar 30. The fixed crossbar 29 is made of channel steel, and the adjustable crossbar 30 is provided. A rectangular steel tube of the same size is used. The fixed crossbar 29 is provided with two first crossbar mounting holes 29a, 29b. One end of the adjustable crossbar 30 is correspondingly provided with two second crossbar mounting holes 30a, 30b, and the other end of the adjustable crossbar 30 is provided. There is a first sleeve connecting hole 30c; the two first rail mounting holes 29a, 29b of the fixed crossbar 20 and the two second rail mounting holes 30a, 30b of the adjustable crossbar 30 are matched and bolted.

Referring to FIG. 22, the upper rotating sleeve 20 and the lower rotating sleeve 21 are identical in structure, and each includes a sleeve 20a and a connecting plate 20b fixed to one side of the sleeve 20a. The center of the connecting plate 20b is provided with a second rotating sleeve connection. The hole 20c, the first sleeve connecting hole 30c of the upper arm 18 and the second sleeve connecting hole 20c of the upper sleeve 20 are bolted, and the first sleeve connecting hole 30c of the lower arm 19 and the lower sleeve 21 are The second swivel connection hole 20c is connected by bolts.

At the same time, the auxiliary connecting hole 20d is further disposed at an obliquely lower corner of the connecting plate 20b away from the sleeve 20c. (The auxiliary connecting hole 20d is used for replacing the second rotating sleeve connecting hole 20c with the adjustable crossbar 30 being inclined upwardly. A swivel connection hole 30c is connected to ensure the vertical of the vertical arm 22).

One end of the fixed crossbar 29 is welded to the arm sleeve 6, and the other end of the fixed crossbar 29 is a concave crescent joint 29c; the connecting end of the adjustable crossbar 30 and the fixed crossbar 29 adopts a rounded transition ( When the bolt is loosened, it is convenient to adjust the butt joint upwards. The other end of the adjustable crossbar 30 is also a concave crescent joint 30d, and the radius of the curved surface of the concave crescent joint 30c, 30d and the upper sleeve 20 (downward) The sleeve 20a of the sleeve 21a has a matching radius of the circumference (for ease of assembly and disassembly, the fixed crossbar 29 and the adjustable crossbar 30 can be easily interfaced with the corresponding upper and lower swivel sleeves 20, 21).

Referring to FIG. 10, the vertical arm 22 includes a vertical rod, and the vertical rod is composed of an upper rod 22a, a middle rod 22c and a lower rod 22b, and the upper connecting sleeve 25 and the lower connecting sleeve 26 are respectively fixedly fixed to the upper rod 22a. And the lower rod 22b, the middle rod 22c is screwed with the upper rod 22a and the lower rod 22b, respectively (removably retaining only the upper rod 22a and the lower rod 22b portion), and the upper rod 22a and the lower rod 22b are respectively connected to the upper rod 22a and the lower rod 22b A first planar bearing 27 is mounted between the upper rotating sleeve 20 and the upper connecting sleeve 25, and a second planar bearing 28 is mounted between the lower rotating sleeve 21 and the lower connecting sleeve 26 for facilitating vertical connection. The arm 22 is rotated and adjusted to drive the arm assembly 12 to turn.

The upper rod 22a is internally provided with a telescopic inner rod 22d by screws (the same manner as the outer telescopic arm of the conventional adjustable small crane), and a plurality of wire holes are arranged on the telescopic inner rod 22d, correspondingly A wire hole is arranged on the rod 22a, and the height of the telescopic inner rod 22d is fixed in the vertical direction by a corresponding screw hole of the screw. The upper end of the telescopic inner rod 22d is matched with the head pulley 14 through the nut and the screw rod 35. connection. The telescopic inner rod 22d is used to adjust the height of the head pulley 14 within a certain range for different installation conditions, thereby facilitating the engagement between the ropes 10 between the pulleys.

Referring to FIG. 20, the head pulley 14 includes a pulley bracket 34, two lower pulleys 38 fixed under the pulley bracket 34, two intermediate pulleys 37 fixed in the middle of the pulley bracket 34, and fixed above the pulley bracket 34. An upper pulley 36, a pulley bracket 34, a bottom plate mounting screw 35 and a telescopic inner rod 22d are connected by a nut. Referring to Fig. 21, the sides of the upper pulley 36, the two intermediate pulleys 37, and the two lower pulleys 38 are arranged in a positive cross, and the wire rope 10 is connected to the pulley hook assembly 16 after passing through any of the pulleys through the center of the cross.

The upper pulley 36, the intermediate pulley 37, and the lower pulley 38 of the head pulley 14 are used to match the course of the wire rope 10 in the obliquely upward direction a, the horizontal direction b, and the obliquely downward direction c, respectively.

A turning lever 23 is mounted on the connecting plate 20b of the lower rotating sleeve 21 via a rotating shaft. Referring to FIG. 23, a side of the lower connecting sleeve 21 adjacent to the turning lever 23 is provided with a concave groove 24 when When the control lever 23 is engaged in the concave groove 24, the vertical arm 22 is locked, and when the control lever 23 is separated from the concave groove 24, the vertical arm 22 can rotate.

Referring to Figure 11, the arm assembly 12 includes an outer arm tube 12a that is coupled to the lower connecting sleeve 26 by a pin, and an inner arm rod that is sleeved within the outer arm tube 12a and has an adjustable length (also using screws and The manner of adjusting the wire hole is not described in detail herein; and as shown in FIG. 12 and FIG. 13, the inner arm is composed of an upper arm 21b and a lower arm 12d, and the end of the upper arm 12b is provided The recess 32 and the end of the lower arm 12d are provided with a convex portion 33 which is engaged with the convex portion 33 and connected by two bolts 12c. When the upper arm rod 12b and the lower arm rod 12d are connected by only one bolt 12c, The angle between the upper arm 12b and the lower arm 12d can be adjusted within a range of 90°-180° (similar to a hinge structure).

When the upper arm and the lower arm are at an angle of less than 180° (as shown in FIG. 11), the upper arm 12b is bolted with an upper pulley 15 for transitioning the wire rope 10 to the pulley hook assembly 16, while the upper arm 12b is A bending arm support rod 31 is connected between the lower arm rods 12d by bolts.

Embodiments of the invention

Embodiment 1

Referring to Fig. 19, the bending arm supporting rod 31 includes an intermediate screw 31a, and a bending arm sleeve 31b screwed to both ends of the intermediate screw 31a, and the bending arm supporting rod 31 fixedly supports the upper arm rod 12b and the lower arm rod 12d. The length can be adjusted according to the degree of bending of the inner wall rod.

The upper arm rod 12b and the upper connecting sleeve 25 are connected by a basket screw 17, and the front end of the upper arm rod 12b is mounted with a pulley hook assembly 16 (the pulley hook assembly 16 can be screwed for easy disassembly, or can be connected to the end of the lower arm rod 12d). Connected, the upper and lower arms are reversed.) The arm sleeve 13 is mounted on the arm sleeve 6. The wire rope 10 of the motor main unit 3 passes through the upright pulley 13 and the head pulley 14 in turn (the inner arm is not straight). The upper upper pulley 15) is connected to the pulley hook assembly 16.

Embodiment 2

Referring to Figure 11, the arm assembly 12 includes an outer arm tube 12a that is coupled to the lower connecting sleeve 26 by a pin, and an inner arm rod that is sleeved within the outer arm tube 12a and has an adjustable length (also using screws and The manner of adjusting the wire hole is not described in detail herein; as shown in FIG. 14 and FIG. 15, the inner arm can also be designed in such a manner that the end of the recess 32 and the upper arm 12b are screwed and convex. The portion 33 is screwed to the end of the lower arm 12d, and the recess 32 and the projection 33 are fitted to each other as a separate concavo-convex connector 40 by bolting as in FIG.

Referring to FIG. 16, when the concave-convex connecting member 40 is detached, the upper arm rod 12b and the lower arm rod 12d can be directly butted by a thread to be used as a straight arm; as shown in FIG. 17, the lower arm rod 12d can be chained as shown in FIG. The concave-convex connector 40 as a whole is reversed to screw the other end of the lower arm 12d to the upper arm 12b as a straight arm.

Embodiment 3

Referring to Figure 11, the arm assembly 12 includes an outer arm tube 12a that is coupled to the lower connecting sleeve 26 by a pin, and an inner arm rod that is sleeved within the outer arm tube 12a and has an adjustable length (also using screws and The manner of adjusting the wire hole is not described in detail here; referring to FIG. 18, the concave-convex connecting member 40 is replaced by an elbow 41. When the inner arm is used as a bending rod, the upper arm is threaded by the elbow 41. 12b and the lower arm rod 12d are connected together; when the inner arm rod is used as a straight rod, the elbow 41 is disassembled, and the upper and lower arm rods are directly threaded and butted together as shown in FIG.

Embodiment 4

The arm assembly of the present invention can also be applied as an arm of a "mast support structure for an adjustable small crane" patent number ZL201621015315.4, which can be better with the existing adjustable mast structure. The combination adjustment method.

Embodiment 5

According to different installation conditions and construction environment, the invention can perform various structural changes to fully meet the construction requirements, as follows:

Figure 1 shows the complete small crane structure, which adapts to the width of the window sill and the narrow or wide window; Figure 24 removes the adjustable crossbar, and the fixed crossbar is directly connected with the upper (lower) swivel sleeve, which can be adapted to the narrow window sill. The case where the window is wide or narrow; FIG. 25 is compared with FIG. 1 to change the inner arm of the arm assembly into a straight rod, which can adapt to the width of the window sill and the width of the window; FIG. 26 is also adjustable as shown in FIG. The crossbar is disassembled, and the fixed crossbar is directly connected with the upper (lower) rotary sleeve, which can be adapted to the case where the window sill is narrow and the window width is wide; FIG. 27 is compared with the first embodiment, and the adjustable crossbar is mounted upturned to adapt to the special Installed under the window width, when the crossbar is tilted up, the auxiliary connecting hole on the upper (lower) rotating sleeve is connected to the first rotating sleeve connecting hole instead of the second rotating sleeve connecting hole to ensure the vertical of the vertical turning arm.

Figure 28 is a view showing the middle rod of the vertical rod in the vertical arm being removed to form an open adjustable frame structure, and the vertical rods in the vertical arm in the other figures are also detachable. An enumeration.

29 to 38 are all the installation cases in which the vertical arm is detached only through the upper (lower) arm connecting arm assembly: wherein, FIG. 29 is respectively connected by the first sleeve connecting holes of the adjustable crossbar The basket screw and the outer arm tube are suitable for the case where the window sill is wide and the window is narrow or wide; FIG. 30 compares the inner arm of the arm assembly into a straight rod as compared with FIG. 29, which can adapt to the width of the window sill and the width of the window; 31 to 34 each disassemble the adjustable crossbar portion, the inner arm bar can be straight and bendable, and the outer arm tube can be mounted and fixed by the inner rail or the outer first rail mounting hole as needed.

35 and FIG. 36 show a conversion structure in which all of the upper arm is retained, and the lower arm is only fixed to the cross bar, and the inner wall bar can be straight and bendable to accommodate the case where the window sill is narrow and the window is wide.

Figure 37 and Figure 38 show the deformation of the adjustable crossbar in the case of disassembling the vertical arm, Figure 37 and Figure 38, which can also be turned down with reference to Figure 35 and Figure 36. The adjustable crossbars of the arms are disassembled and reassembled, and are not listed here.

Industrial applicability

The invention adds the adjusting frame assembly as a connecting member between the arm assembly and the pole assembly on the basis of the existing adjustable small crane, and the adjusting frame is composed of three turning arms and upper and lower connecting sleeves, which can be The construction environment can be freely combined and disassembled. When the vertical arm is retained, the bending of the boom can be realized without the pole sleeve moving. The arm assembly is optimized on the basis of the original inner and outer double poles, and the inner rod part design will be optimized. The inner rod is divided into upper and lower arm rods, and the upper and lower arm rods are connected by a concave-convex structure, and are fixed by bolts. When the single bolt is fixed, the hinge structure can be adjusted in the range of 90°-180° to adjust the bending of the inner rod. The degree of folding, while being fixed by more than two bolts, is the same as that of the conventional straight rod, and realizes the foldable and straightforward function of the arm, which can fully satisfy the window installation of different sizes; the structure of the invention is stable and has a comparative Strong adaptability, according to the actual situation of the construction window, the structural deformation under long distance hoisting, medium distance hoisting and close hoisting can solve the structure of the traditional adjustable small crane Full lifting of various environmental adaptation, truly a multi-purpose machine for the development of small crane industry has made a significant contribution, with some industrial applicability.

Claims

A small crane with an adjustable boom structure, comprising a main body, a pole assembly and an arm assembly, the main body comprising a main base and a motor main body and a pole sleeve disposed on the main base; the pole assembly The utility model comprises a vertical rod, a top hat fixed on the upper end of the vertical pole, a rotating arm sleeve which is set on the vertical pole and supported by the hoop, a jack screw which is set in the lower end of the vertical rod and is set on the jack screw for supporting the pole a screw nut, the jack screw is set in the pole sleeve; characterized in that:

The utility model further comprises an adjustment frame assembly, wherein the adjustment frame assembly is a frame structure composed of an upper arm, a lower arm, an upper sleeve, a lower sleeve and a vertical arm, wherein the upper arm and the lower arm are fixed horizontally a rod and an adjustable cross rod, the fixed cross rod is horizontally fixed on the arm sleeve, and the fixed cross rod is provided with at least one first cross rod mounting hole, and one end of the adjustable cross rod is provided with at least one a second crossbar mounting hole, the other end of the adjustable crossbar is provided with a first swivel sleeve connecting hole; the first crossbar mounting hole of the fixed crossbar is matched with the second crossbar mounting hole of the adjustable crossbar The upper rotating sleeve and the lower rotating sleeve respectively comprise a sleeve and a connecting plate fixed on one side of the sleeve, wherein the connecting plate is provided with a second rotating sleeve connecting hole, and the first rotating arm is first The sleeve connecting hole and the second sleeve connecting hole of the upper sleeve are connected by bolts, and the first sleeve connecting hole of the lower arm and the second sleeve connecting hole of the lower sleeve are connected by bolts; the vertical arm includes a vertical rod, and a head pulley fixed to the top end of the vertical rod; the upper and lower ends of the vertical rod are respectively connected to the upper rotating sleeve Under transfer kit;

The arm assembly includes an outer arm tube connected to the lower connecting sleeve through a pin shaft, and an inner arm rod that is sleeved in the outer arm tube and has an adjustable length; the inner arm rod is composed of an upper arm rod and a lower arm rod. The end of the upper arm is provided with a recess, and the end of the lower arm is provided with a convex portion, and the concave portion cooperates with the convex portion and is connected by at least one bolt, when the upper arm and the lower arm are connected by only one bolt The angle between the upper arm and the lower arm can be adjusted within a range of 90°-180°; the upper arm and the upper connecting sleeve are connected by a basket screw, and the front end of the upper arm is mounted with a pulley hook assembly, the rotating arm A pole pulley is mounted on the sleeve, and the wire rope of the motor main body is sequentially connected through a pole pulley, a head pulley and a pulley hook assembly.
A small crane with an adjustable boom structure according to claim 1, wherein the fixed crossbar is a channel steel, the adjustable crossbar is a rectangular steel tube, and one end of the fixed crossbar is welded On the swivel sleeve, the other end of the fixed crossbar is a concave crescent joint; the connecting end of the adjustable crossbar and the fixed crossbar adopts a rounded transition, and the other end of the adjustable crossbar is also a concave crescent The joint has a curved radius of the concave crescent joint matching the circumferential radius of the sleeve of the upper or lower sleeve.
A small crane with an adjustable boom structure according to claim 1, wherein the vertical rod is composed of an upper rod, a middle rod and a lower rod, and the middle rod is respectively associated with the upper rod and the lower rod Through the screw connection, a telescopic inner rod is mounted in the upper rod by a screw, and an upper end of the telescopic inner rod is coupled with the head pulley through a nut and a screw rod.
The small crane with an adjustable boom structure according to claim 1, wherein a rotating lever is mounted on the connecting plate of the lower rotating sleeve, and the lower connecting sleeve and the turning lever are installed The adjacent one side is provided with a concave groove, and when the control lever is engaged in the concave groove, the vertical arm is locked, and when the control lever is separated from the concave groove, the vertical The arm can rotate.
A small crane with an adjustable boom structure according to claim 1, wherein the second sleeve connection hole of the upper sleeve and the lower sleeve is located at the center of the connecting plate, the connecting plate An auxiliary connecting hole is also provided at an obliquely lower corner away from the sleeve.
A small crane with an adjustable boom structure according to claim 1, wherein when the upper arm and the lower arm are at an angle of less than 180, the upper arm is mounted by bolts for a transition wire rope to an upper pulley of the pulley hook assembly, wherein the upper arm rod and the lower arm rod are connected by bolts with a bending arm support rod, the curved arm support rod includes an intermediate screw, and a bend connected at both ends of the intermediate screw by screwing Arm sleeve.
A small crane with an adjustable boom structure according to claim 1, wherein the head pulley comprises a pulley bracket, and two lower pulleys fixed under the pulley bracket are fixed in the middle of the pulley bracket. Two middle pulleys and one upper pulley fixed above the pulley bracket, the sides of the upper pulley, the two intermediate pulleys and the two lower pulleys are arranged in an orthogonal cross, and the steel rope passes through the cross center and is transferred through any pulley Connected to the pulley hook assembly.
A small crane with an adjustable boom structure according to claim 1, wherein the recess is screwed to an end of the upper arm, and the ends of the convex and lower arm are threaded. Connecting, the recess and the protrusion cooperate and are connected by at least one bolt to be a single concave-convex connection; when the concave-convex connection is disassembled, the upper arm and the lower arm are threadedly butted.
A small crane with an adjustable boom structure according to claim 1 or 3, wherein the upper portion of the vertical rod is provided with an upper connecting sleeve, and the lower portion of the vertical rod is provided with a lower connecting sleeve, The upper connecting sleeve and the lower connecting sleeve are respectively located above the upper rotating sleeve and the lower rotating sleeve, and the upper rotating sleeve and the upper connecting sleeve are connected by a first planar bearing, and the lower rotating sleeve and the lower connecting sleeve are connected by a second Flat bearing connection.