CN211396655U - Arm support and engineering machinery - Google Patents

Abstract

The utility model relates to an engineering machine tool field specifically relates to an arm support and engineering machine tool. The arm support comprises a plurality of sequentially connected arm sections, the arm sections comprise a root arm section group and an end arm section group, and the root arm section group and the end arm section group respectively comprise a plurality of sequentially connected arm sections; at least one arm section in the root arm section group is a bent arm, and an arm section of the end arm section group is a straight arm; at least one arm section of the end arm section group is provided with a lightening hole. Through the technical scheme, the utility model discloses set up the lightening hole at first on the arm festival and reduce the dead weight of every arm festival self. Because the stress condition of the bending arm is more complicated than that of the straight arm, the weight of the straight arm is smaller than that of the bending arm. The bending arm is arranged at the root arm section group, so that the bending arm can be closer to one end of the root of the arm support, the end arm section group close to the tail end of the arm support is arranged to be a straight arm, the longer arm support length can be achieved under the same arm support weight, and the working range of the equipment is enlarged.

Description

Arm support and engineering machinery

Technical Field

The utility model relates to an engineering machine tool field specifically relates to an arm support and engineering machine tool.

Background

In an engineering machine with a boom structure, a boom is generally used as a main bearing part of mechanical equipment and is used for extending the working distance of the equipment. In order to adjust the length of the arm support, the telescopic arm support and the folding arm support are available. For a foldable arm support, under the condition that the working length of the arm support is long and the number of arm sections of the arm support is large and is generally larger than four sections, in order to avoid the overhigh height after folding and improve the folding degree of the whole arm support, besides a common straight arm, a plurality of bending arms are often arranged. The front arm section and the rear arm section which are connected with the bending arms can be folded to different planes, so that the folded height is avoided from being too high. The straight arm is an arm section with the axis of the rotating shaft of the arm section being mutually vertical to the connecting line of the root part and the end part, and the bent arm is an arm section with the axis of the rotating shaft of the arm section being mutually non-vertical to the connecting line of the root part and the end part.

When the arm frame is viewed from above, the center line of the arm section has a broken line, so that the connecting line of the two ends of the arm section and the axis of the arm frame are not in the same straight line. Because the arm support is required to bear loads such as shearing force, torque and the like besides bending moment, the stress condition at the bending arm is more complicated. Therefore, the bent arm is heavier than the straight arm, the weight reduction design is more unfavorable, and the maximization of the length of the arm support cannot be realized under the condition that the weight of the whole machine is limited.

SUMMERY OF THE UTILITY MODEL

The utility model aims at overcoming the too big restriction cantilever crane length problem of cantilever crane weight that prior art exists, providing a cantilever crane and engineering machine tool, this cantilever crane can reach longer cantilever crane length, lifting means's working range under the same cantilever crane weight.

In order to achieve the above object, one aspect of the present invention provides an arm support, including a plurality of sequentially connected arm joints, wherein the plurality of arm joints include a root arm joint group and an end arm joint group, and the root arm joint group and the end arm joint group respectively include a plurality of sequentially connected arm joints; at least one arm section in the root arm section group is a bent arm, and the arm section of the end arm section group is a straight arm; at least one arm section of the end arm section group is provided with a lightening hole.

Preferably, the tail end of the root arm joint group is connected with the end arm joint group, and the other end of the root arm joint group is a head end; at least one arm section of the three arm sections close to the head end of the root arm section group is a bending arm.

Preferably, at least one of the second arm section and the third arm section of the root arm section group from the head end is a bent arm.

Preferably, the second arm section and the third arm section of the root arm section group from the head end are both bending arms.

Preferably, the root arm section group comprises three arm sections, the third arm section from the head end of the root arm section group is a bent arm, and the other two arm sections are straight arms.

Preferably, two sections of arms of the end part arm section group, which are close to the root part arm section group, are provided with lightening holes.

Preferably, the number of arm sections in the end arm section group is at least two.

Preferably, the set of end arm segments comprises three arm segments.

Preferably, the lightening hole is formed in a web plate of the arm section.

Preferably, the lightening holes of the straight arm are distributed in the area between the hinge holes at the two ends of the web plate; a plurality of lightening holes are formed in the web plate.

Preferably, the middle part of the bending arm is provided with a bending part, and the lightening hole is arranged between a root hinged hole at the root of the bending arm and the bending part.

The utility model discloses the second aspect provides an engineering machine tool, engineering machine tool installs the utility model provides a cantilever crane.

Through the technical scheme, the utility model discloses set up the lightening hole at first on the arm festival and reduce the dead weight of every arm festival self. Meanwhile, the overall stress condition of the unfolded cantilever crane can be simplified into a cantilever beam model, and the main stress borne by the cantilever crane is a main bending moment generated by load and self weight. Since the foldable boom is not suitable for heavy-weight hoisting operation, the self weight of the boom occupies a considerable proportion of the stress generated by the bending moment of the whole boom under the condition of insufficient load. The main bending moment borne by the arm support can be effectively reduced by arranging the lightening holes.

Because the bending arm is more complicated than the straight arm in terms of stress, the bending arm is also subjected to stress caused by torsion in the axial direction. When the lightening holes are arranged, more lightening holes can be arranged on the straight arm, and the lightening holes which can be arranged on the bent arm under the condition of meeting the strength requirement are less than those of the straight arm. Compared with the straight arm, the bent arm arranged at the same position after being provided with the lightening holes for lightening is lighter, and the weight of the straight arm is smaller than that of the bent arm. The formula of the bending moment in the cantilever beam model is

Wherein F is external force, L is the length of the moment arm, it can be seen that the position in the arm support, which is farthest from the bending moment, is the root, and the bending moment generated at the root by the external force farther from the root is larger. Therefore, in the utility model, the arm sections of the arm support are divided into two groups of root arm section groups which are closer to one end of the root of the arm support, and the end arm section group is closer to one end of the tail end of the arm support; the bending arm is arranged at the root arm section group, so that the bending arm can be closer to one end of the root of the arm support, the end arm section group close to the tail end of the arm support is arranged to be a straight arm, and the lighter straight arm is closer to the tail end of the arm support. Therefore, the bending moment borne by the root of the arm support can be effectively reduced. The weight of the arm support can be reduced within the same arm support length, and the light weight is realized; in the same way, the longer length of the arm support can be achieved under the same weight of the arm support, and the working range of the equipment is widened.

Drawings

Fig. 1 is a top view of the arm support of the present invention after being unfolded;

fig. 2 is a front view and a top view of the middle straight arm of the present invention;

FIG. 3 is a cross-sectional view A-A of FIG. 2;

fig. 4 is a front plan view and a rear view of the middle folding arm of the present invention.

Description of the reference numerals

1-straight arm 2-bending arm

3-root arm joint group and 4-end arm joint group

5-upper cover plate 6-lower cover plate

7-left web 8-right web

9-lightening hole 10-root hinged hole

11-end hinge hole 12-bend

Detailed Description

In the present invention, the use of directional terms such as "upper, lower, left, and right" in the case where no description is made to the contrary generally means the relationship "inside and outside" shown in fig. 3 means the inside and outside relationship of the outline of the device itself. The term perpendicular herein also includes the case of out-of-plane perpendicularity, which is collectively referred to as perpendicular for ease of description. The arm support is arranged at one end of the vehicle as a root part, and the other end of the arm support, which is far away from the vehicle and carries the actuating mechanism, is an end part; the same is true for a single arm section, and after the arm support is installed and unfolded, the end closer to the vehicle is the root, and the end far away from the vehicle is the end.

In order to carry out the lightweight design to the cantilever crane, the utility model provides a cantilever crane.

As shown in fig. 1 to 4. The arm support comprises a plurality of sequentially connected arm sections, the plurality of arm sections comprise a root arm section group 3 and an end arm section group 4, and the root arm section group 3 and the end arm section group 4 respectively comprise a plurality of sequentially connected arm sections; at least one arm section in the root arm section group 3 is a bent arm 2, and an arm section of the end arm section group 4 is a straight arm 1; at least one arm section of the end arm section group 4 is provided with a lightening hole 9.

As shown in fig. 1, the plurality of arm segments of the boom are divided into two groups, named root arm segment group 3 near the root of the boom and end arm segment group 4 near the end of the boom, it being understood that root arm segment group 3 and end arm segment group 4 are named only for convenience of description. The root arm joint group 3 and the end arm joint group 4 are both composed of continuous arm joints which are connected in sequence, and the root arm joint group 3 and the end arm joint group 4 do not have a cross phenomenon. At least one arm segment of the end arm segment group 4 is provided with a lightening hole, and preferably all the straight arms 1 except the tail-most arm segment can be provided with lightening holes.

And simultaneously the utility model discloses an arm support is to having the cantilever crane of bending arm 2 in the cantilever crane, and to all being the cantilever crane of straight arm 1 in the cantilever crane the utility model discloses an in the scheme for offering lightening hole 9 on the arm festival to the cantilever crane.

The utility model discloses in, the lightening hole 9 that sets up on the arm festival can be various shapes for example can be a plurality of continuous arrangement's in figure 2 trapezoids, also can be triangle-shaped, circular, oval, or other irregular structure, can directly adopt truss structure near terminal arm festival, the preferred finite element topological optimization's that can adopt mode obtains the optimal solution, because the arm festival except self gravity, only the hinge hole at arm festival both ends and the hinge hole of pneumatic cylinder receive external stress, so can assume the extreme atress condition of a during operation and carry out topological optimization.

Through the technical scheme, the utility model discloses set up lightening hole 9 on the arm festival at first and reduce the dead weight of every arm festival self. Meanwhile, the overall stress condition of the unfolded cantilever crane can be simplified into a cantilever beam model, and the main stress borne by the cantilever crane is a main bending moment generated by load and self weight. Since the foldable boom is not suitable for heavy-weight hoisting operation, the self weight of the boom occupies a considerable proportion of the stress generated by the bending moment of the whole boom under the condition of insufficient load. The main bending moment borne by the arm support can be effectively reduced by arranging the lightening holes 9.

Since the bending arm 2 is more complicated to be stressed than the straight arm 1, it is also subjected to stress caused by torsion in the axial direction. When the lightening holes 9 are arranged, more lightening holes 9 can be arranged on the straight arm 1, and the bent arm 2 can be arranged under the condition of meeting the strengthLess lightening holes 9 than the straight arm 1. Compared with the straight arm 1 and the bent arm 2 which is provided with the lightening holes 9 and arranged at the same position after lightening, the weight of the straight arm 1 is smaller than that of the bent arm 2. The formula of the bending moment in the cantilever beam model is

Wherein F is external force, L is the length of the moment arm, it can be seen that the position in the arm support, which is farthest from the bending moment, is the root, and the bending moment generated at the root by the external force farther from the root is larger. Therefore, in the utility model, the arm sections of the arm support are divided into two groups of root arm section groups 3 which are closer to one end of the root of the arm support, and the end arm section group 4 is closer to one end of the tail end of the arm support; the bending arm 2 is arranged at the root arm section group 3, so that the bending arm 2 can be closer to one end of the root of the arm support, the end arm section group 4 close to the tail end of the arm support is arranged as the straight arm 1, and the lighter straight arm 1 is closer to the tail end of the arm support. Therefore, the bending moment borne by the root of the arm support can be effectively reduced. The weight of the arm support can be reduced within the same arm support length, and the light weight is realized; in the same way, the longer length of the arm support can be achieved under the same weight of the arm support, and the working range of the equipment is widened.

According to the utility model discloses a cantilever crane, root arm festival group 3 the tail end with tip arm festival group 4 links to each other, root arm festival group 3's the other end is the head end. At least one arm section of the three arm sections close to the head end of the root arm section group 3 is a bending arm 2. As shown in fig. 1, the bending arm 2 with larger mass is arranged in the three arm sections closest to the root of the arm support, so that the bending moment applied to the root is reduced.

Preferably, at least one of the second arm section and the third arm section of the root arm section group 3 from the head end is a bending arm 2. Since the bending moment applied to the first arm section closest to the root is the largest, if the first arm section is set as the bending arm 2, the weight needs to be increased to improve the structural strength, and meanwhile, the first arm section is set as the bending arm 2, which does not substantially help to improve the folding degree and reduce the folded height of the arm support, in a preferred embodiment, the second arm section or the third arm section is set as the bending arm 2.

Further preferably, in a specific embodiment, the root arm segment group 3 includes three arm segments, the second and third arm segments from the head end of the root arm segment group 3 are bending arms 2, and the first arm segment is a straight arm 1. In another embodiment, as shown in fig. 1, the root arm segment group 3 includes three arm segments, the third arm segment from the head end of the root arm segment group 3 is a bent arm 2, and the other two arm segments are straight arms 1. Under the high condition after comprehensive consideration cantilever crane intensity and folding, the utility model provides a preferred embodiment sets up the third arm festival into bending arm 2, and first arm festival and second arm festival are straight arm 1 simultaneously.

For the end arm section group 4, preferably, in order to set as many arm sections as possible close to the end of the arm support as the straight arm 1 to reduce the bending moment at the root of the arm support, the number of the arm sections in the end arm section group 4 is at least two. In a preferred embodiment, the end arm segment set 4 comprises three arm segments, and each arm segment is the straight arm 1. While a relief hole 9 is provided in the straight arm 1 for the end arm segment set 4 to reduce the mass of the end arm segment set. Preferably, lightening holes 9 are formed in two arm sections of the end arm section group 4 close to the root arm section group 3; the arm section closest to the end of the arm support, which is generally thin, may have its mass reduced by other means than by making a hole, such as by using a truss structure directly or by using a steel tube structure.

Since the arm frame is folded to reduce the folded gap, the cross section of the arm frame is generally rectangular, and as shown in the structure shown in fig. 3, the arm section comprises an upper cover plate 5, a lower cover plate 6, and a left web plate 7 and a right web plate 8 on two sides, and is obtained by welding or direct molding. The main load borne by the arm support during working is dead weight and main bending moment generated by working load, the borne shearing force is usually smaller and less than 20% of the stress of the main bending moment on the cross section of the arm section, and the web plates on the two sides are structures mainly bearing the shearing force. The lightening holes 9 are therefore made in the webs of the arm segments, as shown in fig. 2.

When lightening holes 9 are configured on the straight arm 1, the lightening holes 9 of the straight arm 1 are distributed in the middle area of the hinge holes at the two ends of the web plate; the web plate is provided with a plurality of lightening holes 9. The length of the middle area from the root part hinge hole 10 to the end part hinge hole 11 of the arm section accounts for 80-95% of the length of the whole arm support, a plurality of weight reducing holes 9 which are sequentially arranged are arranged at the middle area, the weight reducing holes 9 formed in the arm section can be in various shapes, such as trapezoid, triangle, circle, ellipse or other irregular shapes, and the arm section close to the tail end can directly adopt a truss structure; preferably, the trapezoid lightening holes 9 shown in fig. 2 are isosceles trapezoids, the symmetry axis of the trapezoids is perpendicular to the axis of the arm section, regular trapezoids with narrow top and wide bottom and inverted trapezoids with narrow top and wide bottom are arranged in sequence along the axis of the arm section in a crossing manner, the plurality of trapezoid lightening holes 9 are at equal intervals, and the distance between two adjacent trapezoid lightening holes 9 is greater than the sum of the lengths of the tops and the bottoms of the trapezoids.

When the lightening holes 9 are arranged on the bending arm 2, the stress condition of the bending arm 2 is more complicated, and the lightening holes 9 cannot be formed in the whole web plate on the straight arm 1 on the premise of ensuring the structural strength. Firstly, a bending part 12 is arranged in the middle of the bending arm 2, a lightening hole 9 is arranged on a web plate between a root hinge hole 10 at the root of the bending arm 2 and the bending part 12, and the lightening hole 9 is preferably arranged near the root hinge hole 10; meanwhile, lightening holes 9 can be arranged on a web plate of the hydraulic cylinder connecting seat in the middle of the arm support, as shown in figure 4.

The utility model discloses another aspect still provides an engineering machine tool, is provided with on this engineering machine tool the utility model provides a cantilever crane. The engineering machinery suitable for the arm support is preferably a concrete pump truck or a fire fighting vehicle. The root part of the arm support is connected with the rotary table, and the arm support is installed on the engineering machinery through the rotary table.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited thereto. The technical idea of the utility model within the scope, can be right the utility model discloses a technical scheme carries out multiple simple variant, makes up with any suitable mode including each concrete technical feature. In order to avoid unnecessary repetition, the present invention does not separately describe various possible combinations. These simple variations and combinations should also be considered as disclosed in the present invention, all falling within the scope of protection of the present invention.

Claims (12)

1. An arm support comprises a plurality of arm sections which are connected in sequence, and is characterized in that the arm sections comprise a root arm section group (3) and an end arm section group (4), and the root arm section group (3) and the end arm section group (4) respectively comprise a plurality of arm sections which are connected in sequence;

at least one arm section in the root arm section group (3) is a bent arm (2), and the arm section of the end arm section group (4) is a straight arm (1); at least one arm section of the end arm section group (4) is provided with a lightening hole (9).

2. The arm support according to claim 1, characterized in that the tail end of the root arm segment group (3) is connected to the end arm segment group (4), and the other end of the root arm segment group (3) is the head end;

at least one arm section of the three arm sections close to the head end of the root arm section group (3) is a bending arm (2).

3. The boom according to claim 2, characterized in that at least one of the second and third arm sections of the root arm section group (3) from the head end is a bending arm (2).

4. The boom according to claim 2, characterized in that the second and third arm sections of the root arm section group (3) from the head end are both bending arms (2).

5. The boom according to claim 2, characterized in that the root arm segment group (3) comprises three arm segments, the third arm segment from the head end of the root arm segment group (3) being a bent arm (2), the other two arm segments being straight arms.

6. The arm support according to any one of claims 1 to 5, characterized in that weight-reducing holes (9) are arranged on two arms of the end arm segment group (4) adjacent to the root arm segment group (3).

7. The boom according to claim 1, characterized in that the number of arm sections in the end arm section group (4) is at least two.

8. The boom according to claim 7, characterized in that the end set of arm sections (4) comprises three arm sections.

9. The boom according to claim 6, characterized in that the lightening holes (9) open on the web of the arm segment.

10. The boom according to claim 9, characterized in that the lightening holes (9) of the straight arm (1) are distributed in the area between the hinge holes at the two ends of the web; the web plate is provided with a plurality of lightening holes (9).

11. The boom according to claim 9, characterized in that the middle of the bending arm (2) has a bend (12), and the lightening hole (9) is arranged between a root hinge hole (10) at the root of the bending arm (2) to the bend (12).

12. A working machine, characterized in that the working machine is equipped with a boom according to any of claims 1-11.

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