JPH0120542Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] The present invention mainly relates to a heat exchanger for construction machinery used in dusty environments such as desert areas and civil engineering work sites. Relates to having an integrally attached grid.

[Technical background of the invention and its problems]

Heat exchanger tubes used in construction machinery are generally made of brass or copper, and relatively often have a wall thickness of 0.25 mm or less. However, when such a heat exchanger is used in an environment with a lot of dust, such as a civil engineering work site, and air is blown by a cooling fan, dust is mixed in with the air being blown. As a result, the relatively soft outer surface of the tube is often damaged by the dust, and the tube is often damaged within a relatively short period of time.
In particular, tube damage is severe at the periphery of the heat exchanger rather than at its center. This is because the dust is subjected to centrifugal force due to the rotation of the cooling fan and has a velocity component in the radial direction. Therefore, damage to the tubes is concentrated particularly at the periphery of the heat exchanger and toward the center side of the fan as shown in FIG. Therefore, conventionally, in order to prevent damage to the tube due to such dust,
A large number of elongated steel plates as shown in the figure were combined vertically and horizontally to form a grid, which was interposed between the core of the heat exchanger and the fan 9 as shown in Figure 1. As shown in FIG. 1, the colliding sand 8 is reflected at one end by the grid 7, and at the same time, the velocity energy of the sand 8 is absorbed. Furthermore, by rectifying the air flow itself using the grid 7, it was possible to prevent sand from being concentrated in a particular part of the tube of the heat exchanger.

However, such conventional grids
As shown in the figure, slits 13 are formed at regular intervals in a thin steel plate, the vertical plate 11 and the horizontal plate 12 are combined at the slits 13, and the combined parts are welded.
Therefore, it is extremely troublesome to assemble the grid, and since there are many welding points, a lot of time and labor are required for manufacturing. Despite this, since welding is used, welding residue and other deposits adhere to the grid surface, making it look unsightly, increasing air resistance, and lowering the air blowing ability. Furthermore, the grid itself becomes relatively large, and the entire heat exchanger including the grid has to become relatively large. Furthermore, there was sand in the blast that passed through the grid 7, which possessed a relatively large velocity energy, thereby shortening the life of the heat exchanger.

Next, in place of the lattice-like grid shown in FIG. 2, a device in which a round bar was passed through the front end of the fin was described in Japanese Unexamined Utility Model Publication No. 55-80693.

However, this idea was only effective when the air flow was formed completely parallel to the tube rows. Generally, this type of heat exchanger blows air with a fan that rotates around the central axis, but as shown in Figure 1, this air blowing is larger toward the periphery, and the direction of the air blowing at the periphery is diagonal to the tube. As shown in FIG. 5, the dust collides with the fan toward the edge on the side of the central axis. Therefore, in the conventional grid using round bars, a large amount of dust passes around the round bars and collides with the tube while retaining a large amount of kinetic energy.

[Summary of the idea]

Therefore, in view of the above problems, the present invention provides a grid that can be easily manufactured, absorbs more velocity energy contained in dust, and reliably prevents damage to the tube. The purpose is to achieve this by the following configuration.

A large number of tubes 2 each having both ends fluid-tightly communicated with a tank 1, a large number of fin plates 3 arranged in parallel at a distance from each other, and to which the tubes 2 pass through and are joined; A large number of flat grid insertion portions 4 are formed in parallel at the upper end with their long axes facing in the width direction of the plate 3.
and a flat grid vertical member 5 penetrating through the insertion portion 4, a groove 6 for trapping dust is formed on the windward end surface of the grid vertical member 5, and is opposed to the heat exchanger core. A heat exchanger with a grid that is blown up by a fan.

[Example of idea]

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

FIG. 6 is a longitudinal cross-sectional view of a main part of the heat exchanger of the present invention, and FIG. 7 is a partial cross-sectional view taken along the line A--A in FIG.
In this embodiment, a heat exchanger core consisting of a tube 2 and a fin plate 3 is disposed between tanks 1, 1 which are vertically spaced apart, and both ends of the tube 2 are communicated with the tank 1, respectively. As shown in FIG. 7, this fin plate 3 has a large number of tube holes spaced apart from each other vertically and horizontally, and the tubes 2 are penetrated through each tube hole, and the spaces between them are integrally brazed. . A grid vertical member 5 whose outer periphery is equal to the outer periphery of the tube 2 and whose windward end face is cut out is passed through the hole in the front row of the fin plate 3. This grid vertical member 5
As is clear from FIG. 6, the length of the tube 2 is slightly shorter than that of the tube 2, and a small gap is formed between the tip thereof and the tube plate 14. In this embodiment, as shown in FIG. 7, the long axis of the grid vertical member 5 and the long axis of the tube 2 substantially coincide with each other in the cross section. Therefore, sand is less likely to collide with the tube 2 located behind the grid vertical member 5. Thereby, damage to the front end edge of the tube 2, which is a problem especially in water leakage accidents, can be prevented. In addition, in this embodiment, since the width of the grid vertical members 5 is relatively wide, the width of the grid vertical members 5,
5, the airflow is narrowed down. Then, since the air flow is effectively rectified, it is possible to prevent the sand 8 from colliding with the tube 2 as shown in FIG. Thereby, the life of the tube 2 can be extended.

In addition, in this embodiment, the windward side end face of the grid vertical member 5 is cut out and a vertical groove 6 is formed therein, so that dust is captured in this groove 6, and its kinetic energy is completely absorbed. The trapped sand flows downward along the longitudinal grooves, or passes between the fin plates 3 with most of its kinetic energy absorbed. Next, FIG. 8 shows a part of the grid vertical member 5 of the second embodiment of the present invention, and FIG. 9 shows that of the third embodiment. Also in these embodiments, each of the grooves 6 is provided, and sand and dust can be efficiently captured by the grooves 6 in the same manner as described above. Next, FIG. 10 shows a fourth embodiment of the present invention, in which the grid vertical member 5 is made of a rectangular tube with one short side cut off. A grid vertical member 5 is fitted into a grid insertion portion 4 formed in a notch in the front edge of the fin plate 3 from the front end side. In addition,
In this embodiment, as shown in FIG.
Since the front edge of the fin plate 3 is perforated slightly more than the front edge of the fin plate 3, the fin plate 3 itself can be protected by the grid vertical member 5, which is relatively strong. That is, even if pebbles or the like collide with the heat exchanger core, the pebbles collide with the front edges of the many grid vertical members 5 located in front of the core and bounce back. Thereby, it is possible to prevent the front edge of the fin plate 3 from being deformed, and it is possible to prevent the air passage from deforming and reducing the heat dissipation effect. Further, the rear edge of the grid insertion portion 4 of the fin plate 3 is slightly bent in a direction perpendicular to the plane thereof to form a guide portion 15 of the grid vertical member 5. Also in FIG. 7, the grid insertion portion 4 is provided with a guide portion as shown in FIG. 10.

Next, a method for manufacturing this heat exchanger will be explained. First, with a large number of fin plates 3 arranged in parallel, the tubes 2 are passed through their respective tube holes. At the same time, the grid vertical member 5 is inserted into the grid insertion portion 4 in the front row. Incidentally, a cladding layer for brazing is previously formed on the outer surface of each tube 2 and the outer surface of the grid vertical member 5, respectively. In this way, each tube 2 and the grid vertical member 5 are inserted into a vacuum furnace or a gas furnace to melt the cladding layer, and the gap between the fin plate 3, the tube 2, and the grid vertical member 5 is melted. braze each. Thereafter, as shown in FIG. 6, the tips of the tubes 2 are passed through the tube plate 14, and the space between them is brazed airtight. Then, the tank 1 is fitted to complete the heat exchanger.

Although the vertical members 5 for the grid in the above embodiment are mainly made of steel, the present invention is not limited thereto, and a synthetic resin material may also be used. In that case, the fin plate 3 and the grid vertical member 5 may be joined with adhesive.

[Effect of idea]

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

(1) The heat exchanger of the present invention is provided with a grid vertical member 5 on its windward front surface, which is flat and has grooves 6 for trapping dust formed in its windward end face. Therefore, the grooves 6 efficiently capture sand,
The energy can be absorbed to effectively prevent damage to the heat exchanger tube. At the same time, since the grid vertical members 5 are formed flat in the ventilation direction, the fans 9 effectively catch the sand and dust colliding in the diagonal direction as shown in Fig. 7 on their sides, causing damage to the tubes on the rear row side. can be prevented.

(2) This heat exchanger is provided with a grid vertical member 5 on its windward front surface, and the grid vertical member 5 is joined to the fin plate 3. The grid, which has the effect of sand protection grid and flow straightening grid, is therefore integral with the heat exchanger core. That is, a grid is formed on the front side of the heat exchanger core itself, which consists of tubes 2 and fin plates 3.
Therefore, the heat exchanger including the grid can be made smaller and lighter. At the same time, unlike conventional grids, the grid can be manufactured together with the heat exchanger core without the need for a separate horizontal member for the grid, reducing material and manufacturing costs, and allowing the heat exchanger including the grid to be manufactured with the heat exchanger core. Can be provided at low cost.

If the outer shape of the grid vertical member 5 is made the same as the outer shape of the tube 2, the present heat exchanger with a grid can be manufactured without changing the manufacturing process of the conventional heat exchanger core.

[Brief explanation of drawings]

Figure 1 is a longitudinal cross-sectional view of a conventional grid;
The figure is a perspective view of the grid, Figure 3 is a partially enlarged perspective view, Figure 4 is an explanatory diagram of the assembly of the grid, and Figure 5 is a perspective view of the grid.
The figure is an explanatory cross-sectional view showing the damaged state of the heat exchanger tube in the absence of a grid, Figure 6 is a longitudinal cross-sectional view of the main part of the heat exchanger of the present invention, and Figure 7 is the arrow A-A in Figure 6. FIG. 8 is a cross-sectional perspective view showing a second embodiment of the grid vertical member 5 of the present invention, FIG. 9 is a perspective view of the third embodiment, and FIG. FIG. 4 is a perspective view of the fourth embodiment. DESCRIPTION OF SYMBOLS 1...tank, 2...tube, 3...fin plate, 4...grid insertion part, 5...vertical member for grid, 6...groove, 7...grid, 8...
Sand, 9...fan, 10...heat exchanger, 11...
Vertical board, 12...Horizontal board, 13...Slit, 14...
...Tube plate, 15...Guide surface.

Claims (1)

[Scope of utility model registration request] A large number of tubes 2 each having both ends fluid-tightly communicated with a tank 1, a large number of fin plates 3 arranged in parallel at a distance from each other, and to which the tubes 2 pass through and are joined; A large number of flat grid insertion portions 4 are formed in parallel at the upper end with their long axes facing in the width direction of the plate 3.
and a flat grid vertical member 5 penetrating through the insertion portion 4, a groove 6 for trapping dust is formed on the windward end surface of the grid vertical member 5, and is opposed to the heat exchanger core. A heat exchanger with a grid that is blown up by a fan.