JPS582190A - Nose boom for crane extensible boom - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lattice end boom for a crane telescoping boom.

In conventional cranes, the length of the telescoping boom is increased by temporarily attaching a tip boom to the end of the telescoping boom to meet special specifications. This type of tip boom uses a kudzu structure to reduce its weight. Furthermore, the tip boom is supported by a cable, and the tubular members forming the top and bottom cords are made of tubes with the same outer diameter and wall thickness.

With such cable-supported lattice structures, axial compressive loads become a problem. That is, the bottom and top cords are compressed. The bending moments due to dead weight and eccentric support are usually small compared to axial loads, the tip boom supported by these cables acts as a pure column and beam loads are not significant. Based on this load, the tubular members forming the top and bottom surfaces have the same outer diameter of 0. However, since the telescopic boom is made large and the cord of the same size described above is long and unsuitable for heavy loads, it is desired to improve the tip of the boom. As a result of various experiments and research on the tip boom with a lattice structure supported by cables, we found that the tip boom, which is not supported by cables and is swingably attached to a telescoping boom, experiences a combination of axial compressive force and bending force. It has been found that this kind of load is fundamentally different from that for something supported by cables, acting as a load and therefore a beam column.

In particular, it comprises a top cord comprising a pair of laterally spaced elongated tubular members, a bottom cord comprising a pair of laterally spaced narrow tubular members, and a rounded connection mechanism connecting these cords to each other. For tip booms, we have found that the compressive negative pressure on the bottom cord is greater than the extensional load on the top cord.Furthermore, we have found that the maximum bending load for the unsupported length of the cord is less than the wall strength of the material due to the rounded bottom. The permissible load for the cord needs to be reduced.Therefore, the correct and effective way to make a lattice tip boom that is not supported by cables is to increase the size of the bottom cord while making the top side much lighter and to increase the strength of the cord. The goal is to find a good balance between the two.

Therefore, in Motoya @, the K can be freely attached and detached from the end of the telescopic boom.
a top cord consisting of a pair of laterally spaced elongated tubular members attached to a lattice-type tip poom not supported by a cable; a bottom cord consisting of a pair of laterally spaced elongated tubular members; and these tubular members. The outer diameter and wall thickness of the tubular member of the top cord, and therefore the weight, are smaller than those of the tubular member of the bottom cord, without sacrificing strength and negative charge layer ability. The cost can be lowered without having to do so.

For example, if the tip pool of the present invention is used, 118111 (42
Approximately 90.711+ for a tip boom of O length (feet)
Good to be able to reduce the weight of (200 bond).

Considering that the material cost of the cord is extremely high, making it lightweight will lead to lower costs.

The present invention will be explained in detail below with reference to the drawings.

The mobile crane 1o shown in FIG. 1 includes a chassis 11, wheels 12 provided on the chassis 11, outriggers 13,
A lower part including a driver's cab 14, a housing 16, a driver m17 provided on the housing 16, and a telescopic boom 18.
, a poom hoist cylinder 19 , and a cable winch 20 .

Figure 1 shows that the outriggers 13 are extended and the wheels are lifted off the ground.
The boom 18 is shown fully extended by the boom hoist cylinder 19.

As shown in FIGS. 1 and 2, it consists of two side plates 23 spaced apart from each other in the lateral direction, and nine pairs of hoist cable pulleys 24 and 25 rotatably supported between them. A known pool head 22 is mounted on top of the pool 18.

Each side plate 23 is provided with two bins (not shown) that are removably engaged with a υ-shaped connector on the proximal end of the tip boom 26, which will be described later. A Ka hoist cable pulley 28 is provided at the top of the tip pool 26, a cable 30 from the winch 20 is suspended from the pulley 28, and a hook 31' is suspended from the cable 30.

As shown in FIGS. 1 to 7, the tip pool 26 has four sides, namely, a top surface 31. Bottom surface 32. Right side 33. Left side 34
It has a lattice-type structure, and its cross-sectional shape becomes smaller from the base end to the distal end.

The distal end pool 26 also has four elongated tubular members 35-38 connected by intersecting struts to be described later.

The tubular members 35, 36 are arranged, for example as a top cord, laterally spaced apart from each other and gradually approaching each other. The tubular members 37' and 38 are arranged, for example, as bottom cords so as to be laterally spaced apart from each other and gradually approach each other. Directly below the center line of the bottom cord and the tubular members 35 and 36 as cords in the vertical direction. Position!1.Top tubular member 3
5.36 is a bottom tubular member 3 which is S* between the two and connected by nine intersecting struts 40°40mm in a known manner.
7.38 are also welded and connected to each other by nine intersecting struts 41.41A.

As shown in FIGS. 5-7, the top tubular members 35, 36 are further connected to respective opposing bottom tubular members 37, 38 by longitudinally spaced intermediate struts 43, 44 to provide the required strength. In order to obtain this, a reinforcing plate 50, 51 of an appropriate shape and size is provided at the base end of the tip pool 26. As mentioned above, the four υ-shaped connectors 55 to 58 are connected to the tip poom 26.
, that is, the base ends of the tubular members 35 to 380, respectively, are connected by welding.

As shown in Figures 2 and 4, the bottom tubular member 37°38K
The maximum length of the unsupported tubular member portion is approximately one degree of the total length of the distal poop 26. The length and length of the unsupported tubular member e.g. two intersecting struts 42.4
2A is the distance between the connection points of the tubular member 37 or 38Ka.

The formula for the length of an unsupported tubular member is □　≦s.

becomes.

In the present invention, the outer diameters and wall thicknesses of the upper tubular members 35, 36 are equal to each other. Similarly, the bottom tubular member 37.
The outer diameter and inner thickness of 38 are also made equal to each other. However, the outer diameter and inner thickness of the bottom tubular member are made larger than those of the top tubular member.

In this way, the weight and cost of the tip pool 26 can be reduced without reducing the load carrying capacity and strength. As an example of the present invention, a test was conducted on a tip end pool 26 having the following dimensions.

The tubular member has a yield point of 6 84/11/(100,000P
, 8. The cross struts were made of cold-drawn and heated chicken steel as shown in I), and the cross struts were made of high yield point low carbon material with yield points 3 & 7i Yuki (5 wires 000P, 8.I) electrically resistance welded.

Length IL811 (42 feet) Base width 0.9 m (3 feet) Base height 1.2 ml + 22.9 country m (4 feet, 9 inches) Point width 0.311.10
．． 2 countries (1 foot, 4 inches) point height Qm
, 26.8 m (O feet, 1036 inches) Bottom tubular member outside diameter 8.3 clR (3,25 inches) Bottom tubular member wall thickness 0.5 tM (0,188 inches) Top tubular member outside diameter 6.4 cm ('L5 inch) Wall thickness of top tubular member 0.4es (0,
116.8 country m (46 inches) unsupported at the cross-stall attachment point
Maximum Length of the Tubular Member As shown in FIG. 2, the dihedral force diagram r shows that the angle α between the longitudinal centerline of the tip poom 26 and the vertical is 15°. xa, 6t (30,000
If a load of 6.8 tons (15,000 pounds) is applied to the cable 30 between the winch 20 and the pulley 28, a load of 6.8 tons (15,000 pounds) is applied.

Although the force diagram F ignores the excursion of the telescopic boom, the elongation of the tip boom, and the deflection at the intersection strut connection point, this diagram shows the relationship between the top tubular members 3 and 36 and the bottom tubular members 37 and 38.
The basic force and stress relationships between

The benefits of using different sized top and bottom cords according to the present invention are shown in the calculations below.

l) Power due to vertical load 0-57.111X1X1000+4&12XR
++2406Xw15°(3CLOOO)-504Xk
a15@(80,000) at -9,,, 012φ 2) Force due to side load MRa-0--03X30,0OOX504 36Rm
R8 sooφ (compression 8.H; extension, H)
Force on the top right cord Force on the top left cord A3 11.1 - 30,806φ (Tension) 2
2 Height MRI-9,06X1'5.000 2406Xccm
15° (30,000) 504Xgk+15' (30,
000)-4&12Re-=Wi', 4.6.49=
g21gBg + Force on the bottom left cord Force height on the bottom right cord Length of unsupported cord and material yield point (100K,
11. Allowable compressive stress L = 461n K-1,0, g-1,0B47K for the bottom cord based on I,)
L 1-OX 46-4 z 4 voices 1.0
847 Allowable stress F; 45.351 = 8. I.

Allowable elongation stress F, -,6X 100-6.00 K, for the top cord,! i, 1. -3 Assuming nine cord materials and mechanical properties bottom cord r 12! $ in O, 11X, 188
(Thick) Mu -1,8930in I=
・2L1228 in'8-1.30631-μ
m1.0847 top code 12.50.0X, 156
(Thickness) Mu = 1.15051m I-, 79341
n'8-. 64371m" μ0.8304 R,; R meeting - straightening axis R1; R4 - lateral rear axis MR, - moment with respect to rear axis line point R1 MR4 - moment L with respect to rear axis line point -
- unsupported cord length K - effective length factor μ, radius of one revolution F, - permissible stress (extension or compression) A - cord cross-sectional area l - moment of inertia of the cord cross-section 8 - section modulus of the cord cross-section

[Brief explanation of the drawing]

FIG. 1 is a side view of a mobile crane equipped with the tip boom of the present invention. , 21st! is a detailed view of the tip boom of the present invention,
Fig. 3 is an enlarged plan view of the tip boom, Fig. 4 is a front view, Fig. 5 is a view from 5-541 in Fig. 4, and Fig. 6 is a 6-541 view in Fig. 4.
FIG. 7 is a 7-7 line view of FIG. 4. lO...Mobile crane, 11...Chassis, 12.
...Wheel, 13...Outrigger, 14.17...Driver's cab, 18...Telescopic boom, 19...Boom hoist silling, 20...Winch, 22...Boom head, 23... ·side! , 24.25.28... Threat cable gooley, 26... Tip boom, 30...
Cable, 31'...Hook, 31...Top surface, 32
...bottom, 33...right side, 34...left side, 3
5-38... Tubular member, 40.4OA, 41141A
, 42e42a...Cross strut, 50.51...Reinforcement plate, 55-5a...U-shaped connector. rt<y, z FIG, 1 -165

Claims (1)

[Claims] (1) An elongated body having a base end, a distal end, a top surface, a bottom surface, and a side surface, the top surface having a pair of laterally spaced apart predetermined outer diameters and wall thicknesses. formed by an m-plane cord consisting of an elongated tubular member having an outer diameter and a wall thickness greater than the outer diameter and inner thickness of the tubular member, the cord being connected to a cross strut. (1) The pair of tubular members forming the top cord gradually approach each other from the base end toward the tip, and the pair of tubular members forming the bottom cord move from the base end to the tip end boom of a crane telescopic boom. The tip boom according to claim 1, wherein the tclts gradually approach each other toward the tip. (3) The tip boom according to claim 2, wherein the tubular members of the top cord and the bottom cord on the same side gradually approach each other from the base end toward the tip end. (4) The longitudinal centerlines of the tubular members of the top and bottom cords on the same side are located in a vertical plane, and the lengths are such that the corresponding intersecting members on the top and bottom cord sides extend. O tip boom (5) according to claim 3. The tip boom according to claim 1, wherein the intersecting struts connect between the pair of tubular members of the top cord and the bottom cord, respectively, and between the top cord and the bottom cord. (6) The tubular members of the top cord and the bottom cord of the same side gradually approach each other from the base end toward the distal end. Claim 1: The inner thickness of the upper cord is greater than that of the tubular member of the upper cord.
The latest boom in modern warfare.