JPS6319406Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a reinforcement structure for the tip of the main boom of a Batshoe.

The main boom of the Batshoe has a roughly rectangular cross section with left and right side plates and upper and lower side plates, and the structure of the tip part is such that a tip bracket plate is extended to the tips of the left and right side plates, and the tips of the top and bottom plates are extended. Each extends to the middle of the tip bracket plate,
The structure is such that a tip closing plate is provided between the tips of the upper and lower side plates. However, in the past, the tip of the tip closing plate was welded to the tips of the upper and lower side plates by butt welding (generally I-type group welding), so that the upper and lower side plates and the tip closing plate appeared to be a single plate. This creates a problem with the strength of the tip, and in order to solve this strength problem, it is necessary to provide a separately prepared reinforcing plate at the tip, which is a time-consuming process in terms of manufacturing. It had become something I needed.

Therefore, in this proposal, when installing the tip closure plate,
Both ends of this tip closure plate are overlapped with the tips of the upper and lower side plates, respectively, and the two are welded together in this overlapping state, making the overlapped portion a reinforcing part for the tip of the main boom, making manufacture easier while at the same time solving the strength problem.

The present invention will be explained below based on embodiments shown in the drawings.

A is a excavation work machine, in which a swivel base 2 is supported on a track running device 1 as a traveling device, and a driving device such as an engine and a control cabin 3 are installed on the swivel base 2. An excavation rig B consisting of a main boom 4, an intermediate boom 5, and a bucket 6 is supported. In addition, 7 in the figure
1 is a base end bracket of excavator B, 8 is a hydraulic cylinder for operating the main boom, 9 is a hydraulic cylinder for operating an intermediate boom, and 10 is a hydraulic cylinder for operating a bucket.

The main boom 4 includes left and right side plates 4a, 4b whose outer shape is approximately doglegged, and left and right side plates 4a, 4b.
The upper and lower side plates 4 are formed by an upper side plate 4e that is bent in a substantially doglegged shape along the upper side and a lower side plate 4d that is bent and formed in a doglegged shape along the lower sides of the right side plates 4a and 4b.
c, 4d are formed into a substantially rectangular cross-section with both side edges projecting outward slightly, and the tips thereof have a thick wall to which the base end of the intermediate boom 5 is pivotally attached to the tips of the left and right side plates 4a, 4b. Tip bracket plates 4e, 4e
are each extended in a forked shape, and the tips of the upper and lower side plates 4c and 4d are respectively extended to the middle portions of the tip bracket plates 4e and 4e, and a tip closure is provided between the tips of the upper and lower side plates 4c and 4d. It has a structure in which a plate 4f is provided. In this case, the tip closing plate 4f has bent portions 11, 11 formed at both ends thereof to overlap with the tip portions of the upper and lower side plates 4c, 4d, and the middle portion thereof is approximately in a state of protruding toward the tip side of the main boom 4. It is formed in a dogleg shape, and the middle part of the tip closing plate 4f is located near the attachment part 5-1 of the intermediate boom 5 to the tip bracket plates 4e, 4e. The mounting structure of this tip closing plate 4f is such that the overlapping bent portions 11, 11 formed at both ends are attached to the upper and lower side plates 4f.
c and 4d, and in the superposed state, the upper end of the closing plate 4f and the leading edge of the upper plate 4c, and the lower end of the closing plate 4f and the leading edge of the lower plate 4d are welded together. In this case, welding is performed by fillet welding at the corners 12, 12 between both end edges of the closing plate 4f and the outer surfaces of the upper and lower side plates 4c, 4d. Also, the corners 13, 13 between the outer edges on both sides of the closing plate 4f and the inner surfaces of the tip brackets 4e, 4e
Fillet welding is also performed, and gaps 14, 14 created between both ends of the closing plate 4f and both ends of the upper and lower side plates 4c, 4d are filled by welding, respectively.

Therefore, at the tip of the main boom 4, both ends of the tip closing plate 4f are overlapped and welded to the tips of the upper and lower side plates 4c and 4d, and the double structure resulting from this overlap is pivotally attached to the tip of the main boom 4. intermediate boom 5
This will strengthen the torsional and tensile strength during rotational movement. That is, when performing work with the excavator B, when the intermediate boom 5 pivoted on the tip bracket plates 4e, 4e at the tip of the main boom 4 moves up and down, the tip brackets 4e, 4e of the main boom 4 move up and down. Although this stress is applied, the tip closing plate 4f at the tip of the main boom 4 disperses the stress to the upper and lower side plates 4e, 4e of the main boom 4 without concentrating it.

This front end closing plate 4f has its upper and lower ends welded to the upper and lower side plates 4c and 4d, and the closing plate 4f
is formed into a substantially dogleg shape, and the outer edges on both sides are welded to the inner surface of the tip bracket plates 4e, 4e near the intermediate boom 5 attachment part 5-1, so that the stress applied to the tip bracket plates 4e, 4e is reduced. This prevents distortion of the main boom 4 by reliably distributing stress to the upper and lower side plates 4c and 4d and avoiding concentration of stress.Also, when welding the tip closing plate 4f, The overlapping bent portion 1 of the closing plate 4f
By fitting the closing plate 4f between the inner surfaces of the closing plates 1 and 11, the positioning of the closing plate 4f can be easily performed.

Furthermore, since the tip closing plate 4f is formed in a substantially dogleg shape, the tip bracket 4 of the main boom 4
When the intermediate boom 5 pivoted to the intermediate booms e and 4e rotates, the surfaces 4-1 and 4-2 of the closing plate 4f guide one side of the intermediate boom 5, causing the intermediate boom 5 to move up and down. It can be fixed even at the limit position, allowing excavation work to be performed in a stable state.

As mentioned above, according to the present proposal, the strength of the main boom tip will be reinforced by the overlapping parts at both ends of the closing plate, and if a separate reinforcing plate is prepared and welded together, it will be possible to This has the effect of saving time and effort. Further, the closing plate can be easily positioned during welding work, which has the effect of simplifying the welding work.

[Brief explanation of the drawing]

FIG. 1 is an overall side view of the backhoe, FIG. 2 is a side view of the main boom, and FIG. 3 is a plan view of the tip of the boom. A: Backhoe, B: Drilling equipment, 4: Main boom, 4a: Left side plate, 4b: Right side plate, 4c: Upper side plate, 4d: Lower side plate, 4e: Tip bracket plate, 4
f: tip closure plate, 11: corner.

Claims (1)

[Scope of utility model registration request] The left and right side plates 4a, 4b and the upper and lower side plates 4c, 4d are formed into a substantially rectangular cross section, and thick tip bracket plates 4e, 4e are provided extending in a bifurcated shape at the tips of the left and right side plates 4a, 4b, respectively. In the main boom of a backhoe, the tips of the upper and lower side plates 4c and 4d are extended to the middle of the tip bracket plates 4e and 4e, respectively, and a tip closing plate 4f is provided between the tips of the upper and lower side plates 4c and 4d. The distal end closing plate 4f is formed into a substantially dogleg shape, and the overlapping bent portions 11, 11 formed at the upper and lower ends thereof are superimposed on the distal ends of the upper and lower side plates 4c, 4d, respectively, and in this superposed state, both are bonded. At the same time, both outer edges of the closing plate 4f and the tip bracket plate 4e,
4e and the corner portions 13, 13 are welded to each other, and the middle portion of the closing plate 4f is located near the attachment portion 5-1 of the intermediate boom 5 of the tip bracket plates 4e, 4e. Reinforcement structure at the tip of the main boom of Naru Batsukuhoe.