JPH0541320U - Fiber-reinforced plastic boom - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a boom made of fiber reinforced plastic that can be manufactured by a small number of steps and that can maintain electrical insulation even when the glass fiber layer on the outer surface is damaged. [Structure] The fiber-reinforced plastic boom 12 is formed by forming an epoxy resin-based elastic adhesive layer 12b on the outer peripheral surface of a core boom 12a. Next, the elastic adhesive layer 12
It is formed by mounting a sheet member 12c formed of fiber reinforced plastic on b.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fiber-reinforced plastic boom used for a work vehicle with a boom such as an aerial work vehicle.

[0002]

[Prior Art]

 For example, an aerial work vehicle is equipped with a boom device that can be raised and lowered freely. This boom device is constructed by telescopically inserting the tip boom into a telescopic boom. The work platform attached to the tip of the boom device can be raised and lowered by such hoisting and retracting operations of the boom device, enabling work at any height. In the aerial work vehicle used for electric construction, the tip boom is made of fiber reinforced plastic which is an electrically insulating material. As a result, when the tip boom contacts the electric wire or the like, it is possible to prevent the electric shock of the worker who is on the workbench.

By the way, when manufacturing such a boom made of fiber reinforced plastic, in order to increase its strength, a so-called filament winding molding method, that is, a mandrel formed from steel or the like is used as a roving helical. In many cases, the method of alternating winding and parallel winding was adopted. The roving is a bundle of surface-treated bundles of several hundreds of fibers each having a diameter of about 10 microns, which are generally arranged in parallel with each other without twisting. The helical winding means winding with the fiber direction of the roving inclined by 20 to 30 degrees with respect to the longitudinal axis of the mandrel. The parallel wrapping refers to wrapping the roving fibers in a state where the fiber direction of the roving is close to the circumferential direction of the mandrel, while adjoining adjacent parts to each other. Then, by repeating these helical winding and parallel winding many times, a predetermined thickness and strength can be obtained. After winding the roving and hardening it by pressing, the mandrel is pulled out, and the fiber-reinforced plastic boom is completed.

[0004]

[Problems to be solved by the device]

 However, in such a filament winding molding method, it is necessary to repeat helical winding for winding and parallel winding, and to pull out the mandrel. There was a problem that it would be high.

The present invention has been made in view of the above problems, and can be manufactured with a small number of steps, that is, at low cost, and further, even when the glass fiber layer on the outer surface is damaged, it has an electrical insulating property. The purpose is to provide a boom made of fiber reinforced plastic that can maintain

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, in the fiber reinforced plastic boom of the present invention, first, an epoxy resin-based elastic adhesive layer is formed on the outer peripheral surface of the core boom. Then, a sheet member made of fiber reinforced plastic is mounted on the elastic adhesive layer to form the fiber reinforced plastic boom. A roving cloth may be wound instead of the sheet member. The roving cloth is a plain weave cloth in which rovings are simply arranged on the weft yarn and the warp yarn.

[0007]

[Action]

 In such a fiber-reinforced plastic boom, since the epoxy resin-based elastic adhesive layer is formed on the outer periphery of the core boom, even if the glass fiber layer formed on it is damaged, the electrical insulation is elastic. Maintained in the adhesive layer. In addition, at the time of manufacturing, since it is sufficient to attach the sheet member on the elastic adhesive layer, the number of steps can be reduced and manufacturing can be performed at low cost as compared with the conventional method. The same applies when winding a roving cloth.

[0008]

Embodiments Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, an aerial work vehicle equipped with the fiber-reinforced plastic boom of the present invention will be described with reference to FIG. At the rear of the vehicle body 31 of the aerial work vehicle 30, a swivel base 32 is attached which is capable of horizontally swiveling with respect to the vehicle body 31. The boom 10 is attached to the upper part of the swivel base 32. The boom 10 is formed in a telescopic shape from a base end boom 11 that is pivotally attached to a swivel base 32 so as to be up and down, and a tip boom 12 that is inserted into the base end boom 11 so as to extend and contract. In order to allow the distal boom 12 to smoothly expand and contract with respect to the base boom 11, the inner bottom surface of the distal end of the proximal boom 11 contacts the lower corner portion of the distal boom 12 while rotating, and the distal end thereof is rotated. A guide roller 15 for guiding the extension and contraction of the boom 12 is attached. Further, a workbench 35 is attached to the tip of the tip boom 12. An operator who rides on the work table 35 can move to an arbitrary high place and perform work through the turning operation of the turning table 32 and the hoisting / extending operation of the boom 10.

Here, the tip boom 12 is made of a fiber-reinforced plastic having high electric insulation so as to maintain an electric insulation state between the workbench 35 and the vehicle body 31 (ground). More specifically, as shown in FIGS. 1 and 2, first, a thick elastic epoxy resin adhesive is first applied to the outer periphery of the core boom 12a formed of steel or the like in the shape of a hollow prism, and the elastic adhesive layer is formed. 12b is formed. As the epoxy resin-based elastic adhesive, a two-liquid mixing type room temperature curing type (for example, PM200 manufactured by Cemendine) is preferable. Further, as the curing agent, for example, a special silicone modified polymer is used. This elastic adhesive has excellent electrical insulation properties, which ensures the electrical insulation properties of the tip boom 12.

However, merely forming the elastic adhesive layer 12b in this manner is insufficient in strength. Therefore, on the elastic adhesive layer 12b, the fiber-reinforced plastic sheet members 12c and 12c, which are formed in advance so as to cover the elastic adhesive layer 12b, are formed by dividing the hollow prism into upper and lower halves. . Instead of the sheet members 12c and 12c, a roving cloth (not shown) made of glass fiber may be wound several times. In this way, a predetermined thickness is formed as the tip boom 12, and the strength is secured.

Then, the shape is adjusted by hardening by pressing. A clamp jig (not shown) made of transparent acrylic is used for the press. With this clamp jig, pressing can be performed without hindering the curing of the elastic adhesive by ultraviolet rays. However, during pressing, the sheet members 12c, 12c or the rowing cloth may be damaged. However, in the present tip boom 12, the electric insulation is secured in the elastic adhesive layer 12b despite such damage. Therefore, even if the boom 10 is used as it is, the worker can safely operate.

[0012]

[Effect of the device]

 As described above, in the fiber-reinforced plastic boom of the present invention, first, the elastic adhesive layer having high electric insulation is formed on the outer periphery of the core boom. Therefore, even if the glass fiber layer formed on the elastic adhesive layer is damaged, the electric adhesive property of the boom can be maintained in the elastic adhesive layer. Also, at the time of manufacturing, it is only necessary to attach a sheet member made of fiber reinforced plastic on the elastic adhesive layer, and it is not necessary to wind the roving as in the conventional case. It can be manufactured at a cost. Even when a roving cloth is wrapped around instead of the sheet member, it can be manufactured at low cost as well.

[Brief description of drawings]

FIG. 1 is a side view of a fiber-reinforced plastic boom according to the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a side view of an aerial work vehicle equipped with the fiber-reinforced plastic boom.

[Explanation of symbols]

 10 Boom 12 Tip Boom (Boom Made of Fiber Reinforced Plastic) 12a Core Boom 12b Elastic Adhesive Layer 12c Sheet Member

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B66F 11/04 8611-3F // B05C 9/00 6804-4D B29L 9:00 4F

Claims (2)

[Scope of utility model registration request] 1. An epoxy resin-based elastic adhesive layer is formed on the outer peripheral surface of a core boom, and a sheet member molded of fiber reinforced plastic is attached to the elastic adhesive layer to form the elastic adhesive layer. A boom made of fiber-reinforced plastic. 2. The fiber-reinforced plastic boom according to claim 1, wherein a roving cloth made of glass fiber is wound around the elastic adhesive layer instead of the sheet member.