JPH0470557B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat exchanger used in a dusty environment such as a civil engineering work site or a desert area, and to a grid for protecting the heat exchanger.

[Prior art and its problems]

BACKGROUND ART When a heat exchanger used for construction machinery and the like blows air with a cooling fan, dust gets mixed into the air. Then, there is a risk that the outer surface of the tube will be damaged by the dust and the tube will be damaged within a relatively short period of time. Therefore, in order to prevent damage to the tube due to such dust, a fifth
A grid 6 as shown in Figures 6 and 6 was used. That is, the grid 6 is placed on the ventilation side of the heat exchanger 5.
The grid 6 captures the dust in the air that is accelerated in the front-rear direction and circumferential direction by the cooling fan, absorbs its kinetic energy, and transfers it to the heat exchanger 5.
This is to prevent damage to the product. However, such a grid has the disadvantage that it is extremely troublesome to manufacture because it involves combining plates in a grid pattern and welding them together. Therefore,
Conventionally, there has been a proposal in which elements are formed by forming plate materials into a trapezoidal wave shape, and the elements are laminated on each other in the thickness direction to form a mesh-like surface pattern. Each element was fixed by brazing and integrated. Although such a grid requires relatively few man-hours to manufacture and can be easily manufactured, according to experiments conducted by the present inventors, such a conventional grid has the drawback of lacking vibration resistance. That is,
Vibration tests revealed that the vibrations were especially intense in the center of the grid, causing the brazing material in that area to fatigue and eventually causing the brazed parts of each element to separate.

Therefore, the conventional idea described in Japanese Utility Model Application Publication No. 54-165928 for the purpose of reinforcing the grid was to arrange reinforcing strips in a cross shape from the frame around the grid, and to connect the strips and each element. The end faces were joined by welding.

This type of welding work is extremely troublesome, and in order to secure a sufficient welding surface, flat plates must be arranged in a cross shape in the center of the grid, which increases the flow resistance of the grid and reduces the amount of ventilation in the heat exchanger. There were drawbacks that reduced it. Further, there was also a drawback that the appearance of the welded part was made unsightly and the commercial value was lowered.

[Summary of the invention]

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned problems and provide a grid that has extremely high vibration resistance and is easy to manufacture.The gist of the present invention is as follows.

That is, a large number of elements 2 constituting the grid
is made by bending a metal strip into a trapezoidal or rectangular wave shape, with at least one surface coated with a brazing material, and a burring hole is formed at one of the top and bottom of the wave, and the burring A hole is formed in the other side so as to match the outer periphery of the part. Then, a large number of elements 2, 2 are stacked in the thickness direction, the crests and bottoms of the waves of adjacent elements are brought into contact with each other, and a plurality of fastening rods 3 having a circular cross section are inserted into each of the perforated holes 1. , by attaching a fastening member to the end thereof, each element 2, 2 is fastened to each other. Then, in a state where each of the fastening rods 3 is fastened, the top and bottom of the wave are integrated together with the fastening rod 3 in a high-temperature furnace by brazing,
A feature is that both ends of the fastening rod 3 are inserted into holes 9 formed in the frame-like frames 7 and 8, and the insertion portions are fixed by welding.

[Embodiments of the invention]

Next, one embodiment of the present invention will be described based on the drawings.

Fig. 1 is a partially enlarged view of Fig. 2, Fig. 2 is a schematic elevational view of the main part of the present invention, Fig. 3 is a partially enlarged perspective view of the element 2, and Fig. 4 is an explanation of assembly of the present grid. It is a diagram.

In this embodiment, each element 2 of the grid bends a strip of steel plate into a trapezoidal wave shape as shown in FIGS. 3 and 1, and holes 1 are formed at the top and bottom of the wave, respectively. The perforation hole 1 at the top of the wave is formed in a burring shape, and its outer diameter is configured to match the perforation hole 1 at the bottom. Therefore, many such elements are added to the first
As shown in Figures to Figure 4, the elements are laminated in the thickness direction, and the crests and bottoms of the waves of adjacent elements are fitted into each other,
The fastening rods 3 are inserted into the drilled holes 1. Then, it is fastened and fixed with a nut 4. Note that the surfaces of each element 2 and fastening rod 3 are solder-plated in advance. Therefore, they are inserted into a furnace in the state shown in FIG. 2, and the solder is melted, thereby brazing and fixing them together. Therefore, in this grid, the fastening rod 3 itself serves as a positioning jig for brazing each element, and also serves as a component of the grid itself. As shown in FIG. 4, frames 7 and 8 are attached to the outer periphery of the grid body thus integrally formed, and the frames 7 and 8 are joined by welding or the like.

In this embodiment, the frame 7 constituting the side plate is provided with holes 9 at intervals of the fastening rods 3 as shown in FIG. It is welded as shown in Figure 1.

〔Effect of the invention〕

As is clear from the above description, the heat exchanger grid of the present invention has the following configuration.

That is, a large number of elements 2 constituting the grid
This is made by bending a metal strip into a trapezoidal wave shape or a rectangular wave shape, and a plurality of perforated holes 1 are formed spaced apart from each other in the longitudinal direction. A large number of such elements 2, 2 are stacked in the thickness direction so that the crests and bottoms of the waves of adjacent elements are in contact with each other. In this state, the fastening rods 3 are inserted into each of the perforated holes 1 to fasten the elements together. In this state, they are integrally fixed by brazing.

The grid of the present invention has the above configuration and has the following effects.

(1) In the grid of the present invention, the fastening rods 3 are inserted between each element and are integrally fixed with the fastening rods 3 by brazing, resulting in a grid with high vibration resistance. That is, in addition to brazing the elements together, they are also integrated by the fastening rod 3, which increases the bonding force between them and dramatically improves the vibration resistance.

(2) In addition, the fastening rod 3 itself has a grid effect against dust, and when the dust collides with the fastening rod 3, the kinetic energy of the dust is absorbed, causing damage to the heat exchanger, especially its tubes. can be more effectively prevented. Furthermore, since the fastening rod 3 has a circular cross section, the fluid resistance of the airflow passing through the grid does not become so large. And it becomes part of a good-looking grit. Furthermore, both ends of the fastening rod 3 are inserted into the perforated holes 9 of the frame-shaped frames 7 and 8, and the insertion portions are fixed by welding.
The frame and the element can be integrated very easily, and from this point of view as well, manufacturing is easy and earthquake resistance is improved.

(3) In addition, according to this grid, the fastening rod 3 itself can be used as a positioning member during brazing, so it is easy to manufacture this grid, and it is possible to perform brazing reliably and create a reliable grid. It has the effect of being able to be manufactured at low cost.

[Brief explanation of the drawing]

Fig. 1 is a partially enlarged view of Fig. 2, Fig. 2 is a schematic elevation view of the main part of the present invention, Fig. 3 is a partially enlarged perspective view of the element 2, and Fig. 4 is an explanation of the assembly of the present grid. 5 is a perspective view of a heat exchanger 5 having a conventional grid 6, and FIG. 6 is an enlarged perspective view of a main part of the conventional grid. 1... Drilling hole, 2... Element, 3... Fastening rod, 4... Nut, 5... Heat exchanger, 6... Grid, 7, 8... Frame, 9... Hole, 10...
welded part.

Claims (1)

[Claims] 1 A metal strip coated with a brazing material on at least one surface is bent into a trapezoidal wave shape or a rectangular wave shape, a burring hole is formed at one of the top and bottom of the wave, and a burring hole is formed on the outer periphery of the burring portion. A large number of elements 2 with perforated holes formed on the other side so as to match each other, and a large number of elements 2, 2 are stacked in the thickness direction, and the crests and bottoms of the waves of adjacent elements are brought into contact with each other to form the perforated holes in each of the elements. A plurality of fasteners each having a circular cross section in which each element 2, 2 is fastened to each other by being inserted into each of the perforated holes 1 with the holes aligned and fitted, and by attaching a fastening member to the end thereof. rods 3, and in a state where each of the fastening rods 3 is fastened together with the fastening rods 3, the crest and bottom of the wave are integrated by brazing in a high temperature furnace,
A heat exchanger grid in which both ends of the fastening rod 3 are inserted into holes 9 formed in frame-shaped frames 7 and 8, and the insertion portions are fixed by welding.