JPH08110186A - Spiral pipe for cooling, its manufacture, and cooling device employing it - Google Patents

Abstract

PURPOSE: To enable forming a flat cooling passageway in a spiral with good accuracy and in a simple manner by winding a flat pipe in a spiral around an axis making right angles to the directions in which the pipe is flat and by forming ridges and troughs extending radially from the axis of the spiral in the surface of the pipe. CONSTITUTION: In a ridge-and-trough-forming process 11 a pair of metal molds 15 which are put close to and separated from each other are placed past feeding rolls 14 and made to compress a pipe 2 to form ridges and troughs 5 in its surface. A bending process 12 comprises a forward bending step 12a for bending the pipe 2 into a gentle right-angled bend and a spirally bending step 12b for winding the bent pipe 2 around a guide shaft in a spiral. Between these forward bending step 12a and spirally bending step 12b of the bending process 12 a crushing process 13 is provided, wherein metal molds 22, 23 designed to work in a pair and in a manner of being put close together and separated are made to compress the pipe 2 into a flat product by a technique of drawing. As a result, compared with, for example, a spiral pipe consisting of a plain, circular pipe wound in a spiral, the surface area of the cooling passageway is enlarged, a greater effect can be achieved in discharge of heat, and the cooling is effected with good efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spiral tube for cooling a fluid such as oil or water, a method for manufacturing the spiral tube, and a cooling device using the spiral tube.

[0002]

2. Description of the Related Art Many transport machines such as automobiles and various industrial machines are equipped with cooling devices for cooling fluids such as oil and water.

This type of cooling device is provided with a curved or spirally bent cooling passage for circulating a fluid serving as a heat medium, and by moving the fluid inside the passage, a heat radiating action is provided. It takes heat from the fluid and cools it.

In the above cooling device, it is required that the internal surface area of the cooling passage is as large as possible in order to obtain a large heat radiation effect, and that the whole of the cooling passage to be incorporated into the machine should be compact in shape. It Further, in transportation machines such as automobiles, the cooling device is required to be as light as possible.

As a means to meet such a demand, there is a method in which the cooling passage has a flat shape and the passage is spirally wound with a diameter as small as possible.
The internal surface area of the passage can be increased and the overall shape can be made compact.

[0006]

However, since a flattened pipe member such as a metal pipe has an increased mechanical strength in the flattened direction, it is difficult to spirally wind the pipe member with a small diameter. However, there is a problem that the entire shape tends to be large.

On the contrary, there is also a method in which the pipe member is spirally wound and then crushed into a flat shape, but a strong compressive stress acts on the inner peripheral surface of the spirally bent pipe member. Therefore, when the pipe member is strongly crushed, abnormal deformation and cracks easily occur on the inner peripheral surface, and there is a problem that it cannot be formed into a sufficiently thin flat shape.

On the other hand, as a solution to the above problem, Japanese Patent Laid-Open No. 6-159888 discloses that two plate members 42, which are spirally deformed, are formed on the outside of the straight pipe 41 as shown in FIG. , 43 are wound and joined, and the plate members 42, 4
It is proposed that a flat cooling passage 44 is formed between the three.

The proposed structure has the advantage that the flat cooling passages 44 can be stacked with a spiral having a small diameter, but the ends of the plate members 41 and 42 must be joined by welding or the like. Therefore, there is a problem that manufacturing requires a lot of labor and cost.

Further, it is difficult to liquid-tightly join the entire circumferences of the end portions of the plate members 41 and 42 by welding or the like, and the cooling passage 4
There is a drawback that the fluid in 4 easily leaks to the outside.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above problems and provide a cooling spiral tube capable of accurately forming a flat spiral cooling passage by a simple method, and a manufacturing method thereof. .

Another object of the present invention is to provide a cooling device which can exhibit a high heat radiation effect by using the above spiral tube.

[0013]

In order to solve the above-mentioned problems, the cooling spiral tube of the present invention has a flat pipe spirally wound around an axis orthogonal to the flat direction of the flat pipe. A plurality of irregularities extending from the central axis of the spiral in the radial direction are formed on the surface.

Further, in the method for manufacturing a spiral pipe according to the present invention, a concavo-convex forming step of forming a plurality of concavities and convexities along the length direction on the surface of the pipe, a bending step of spirally winding the pipe, and the pipe The method comprises a squeezing step of flattening in a direction orthogonal to the direction in which the spiral advances.

In the above-mentioned manufacturing method, in the concavo-convex forming step, the entire circumference of the surface of the pipe is expanded or reduced at a constant pitch to form concavities and convexities, and a bellows tubular pipe is molded as a whole. Alternatively, irregularities can be formed on the surface of the pipe at unequal pitches.

On the other hand, according to the first cooling device of the present invention, the heat medium inflow and outflow ports are respectively formed at both ends of the cooling spiral tube having the above structure, and the heat medium is provided inside the spiral tube. I decided to distribute it.

In the second cooling device, a straight pipe is inserted inside the cooling spiral pipe having the above structure, and the straight pipe and the inner circumference of the spiral pipe surrounding the straight pipe are communicated with each other, and The inlet and outlet of the heat medium are formed at both ends.

[0018]

In the above-described cooling spiral tube and its manufacturing method, by providing a plurality of irregularities on the surface of the pipe, when the pipe is deformed, each irregularity part expands and contracts,
It functions as a joint that flexibly bends the pipe surface.

Therefore, the pipe can be crushed into a thin flat shape with a small force, or can be spirally wound with a small diameter, and a compact spiral tube having no cracks on the surface can be formed.

Further, since the continuous pipe is spirally wound, there is no joint by welding or the like, and a cooling passage without fluid leakage can be formed.

On the other hand, in the first and second cooling devices described above, since the spiral tube through which the fluid flows has a flat shape and a plurality of irregularities are formed on the surface, the internal surface area of the cooling passage is small. It becomes remarkably large, and a large heat dissipation effect can be exhibited.

[0022]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a cooling spiral tube of the embodiment.

In this spiral tube 1, a flatly shaped pipe 2 is spirally wound around an axis A orthogonal to the flattening direction, and a fluid as a heat medium is introduced into one end of the pipe 2. A port 3 and a fluid discharge port 4 are formed at the other end.

On the surface of the pipe 2, a large number of irregularities 5 extending in the radial direction from the central axis A of the spiral are formed. The concavities and convexities 5 are formed on the upper and lower surfaces of the flattened pipe 2 so as to be continuous from the inner diameter of the pipe 2 to the outer diameter side. It is formed so that the radial side expands.

Next, a method for manufacturing the above spiral tube 1 will be described.

FIG. 2 shows the entire steps of the manufacturing method of the embodiment. In this method, the concavo-convex forming step 11 for forming a plurality of concavities and convexities 5 on the surface of the pipe 2 and the molded pipe 2 are spirally formed. It consists of a bending step 12 of winding and a crushing step 13 of flattening the pipe 2.

Although not shown in the figure, a process for forming a pipe by rolling a flat plate, or a process for welding and joining the mating portions of the formed pipe-shaped product is omitted in the preceding step of the concavo-convex forming step 11. A pipe process is provided so that the pipe 2 produced can be continuously supplied to the forming process 11.

In the concavo-convex forming step 11, as shown in FIG. 3, a pair of metal molds 15 and 15 approaching and separating from each other are arranged behind the feed rolls 14 and 14, and the metal molds 15 and 15 are attached to the pipe 2. By pressure bonding, the unevenness 5 is formed on the pipe surface.

A plurality of semicircular projections 16 and grooves 17 are alternately formed on the crimping surface of each of the molds 15 and 15, and the molds 15 and 15 are attached to the pipe in synchronization with the feeding of the pipe 2. By crimping, an annular large-diameter portion 6 and a small-diameter portion 7 are continuously formed at a constant pitch on the surface of the pipe 2, and the bellows tubular pipe 2 is formed as a whole.

On the other hand, in the bending step 12, as shown in FIGS. 4 and 6, a pre-bending step 12a for bending the pipe 2 in a direction at a large angle and a guide shaft 18 for bending the bent pipe 2 are provided.
And a spiral bending step 12b in which the pipe 2 is spirally wound around, and the pipe 2 is deformed into a small spiral shape with a required inner diameter by combining these two steps 12a and 12b.

In FIGS. 4 and 6, the pre-bending step 12 is performed.
Two drive rolls 19 and one guide roll 20 are attached to a.
Also, in the spiral bending step 12b, three drive rolls 20 and 1 are used.
Although two guide damages and 21 are arranged, the number and arrangement of rolls and guides can be arbitrarily selected according to the diameter of the pipe 2 or the diameter of the spiral.

In this bending step 12, since a large number of large-diameter portions 6 and small-diameter portions 7 are alternately formed on the surface of the pipe 2 in the concavo-convex forming step 11, the pipe 2 is formed by the drive rolls 19 and 21 and the guide 22. When a bending force is applied to, the small-diameter portions 7 of the unevenness 5 contract on the inner diameter side of the spiral and expand on the outer diameter side to flex the pipe 2 flexibly. That is, since each small-diameter portion 7 absorbs the compression and expansion of the pipe, the pipe 2 has each unevenness 5
Becomes a joint and bends smoothly. Therefore, the pipe 2 having the unevenness can be deformed into an arbitrary shape with a small force, and can be wound into a spiral shape having a smaller curvature than an ordinary round pipe having no unevenness.

As shown in FIGS. 2 and 5, the crushing step 13 is arranged between the pre-bending step 12a and the spiral bending step 12b in the bending step 12, and the pair of molds 22 and 23 approaching and separating from each other. By crimping to the pipe 2,
The pipe 2 is flattened and pressed.

In this crushing step 13, the pipe 2
When the pipe 2 is crushed by the molds 22 and 23, the small diameter portion 7 of each unevenness 5 expands and absorbs the excessive deformation of the pipe surface. As a result, the pipe 2 can be smoothly deformed. Therefore, the pipe 2 can be deformed into a thin flat shape without causing cracks or abnormal deformation on the surface of the pipe 2.

The crushing step 13 may be arranged not in the middle of the bending step 12 but on the front side of the front bending step 12a or the rear side of the spiral bending step 12b.

The spiral tube 1 formed by the above method
In (see FIG. 1), since the cooling passage 8 formed inside the pipe 2 is flat and spirally wound and a large number of irregularities 5 are formed on the entire surface, the surface area of the cooling passage 8 is , A conventional spiral tube in which a round pipe is wound spirally,
The size is significantly larger than that of the spiral tube proposed in JP-A-6-159888. Therefore, when a fluid such as oil or water, which is a heat medium, is introduced from the inlet 3 into the cooling passage 8 and circulated in the passage 8, a large heat radiation effect is obtained and efficient cooling is performed. You can

Further, since the pipe 2 is continuously formed from a round pipe and has no joint portion such as a welded portion on the peripheral surface, the fluid does not leak from the cooling passage 8.

FIG. 7 shows another embodiment of the unevenness formed on the surface of the pipe. In FIG. 7A, the unevenness 5 is formed on the surface of the pipe 2 at an unequal pitch. Further, in FIG. 7 (b), a spiral projection 9 is formed on the surface of the pipe 2 so that the entire surface has an uneven shape.

In this way, the unevenness has an uneven pitch,
Even in the spiral shape, since the large diameter portion and the small diameter portion of each unevenness absorb the compression and expansion of the pipe surface, the pipe can be bent smoothly and comfortably.

On the other hand, FIG. 8 shows a cooling device of the embodiment. In this device, a straight tube 31 is inserted inside the spiral tube 1 formed by the above-described method, and the straight tube 31 and the spiral tube 1 are inserted.
An opening 32 is provided on the inner peripheral surface of the so as to communicate the insides of both.

Further, a fluid inlet 33 and a fluid outlet 34 are provided at both ends of the straight tube 31 so that the fluid is circulated into the straight tube 31 and the spiral tube 1.

[0042]

As described above, according to the present invention, a plurality of irregularities are provided on the surface of the pipe, and the irregularities absorb the deformation to smoothly deform the pipe, so that the cooling spiral tube is flat and wound with a small curvature. Can be accurately formed.

Further, the surface area of the pipe is increased due to the unevenness provided on the surface of the pipe, and since the pipe itself has no joint portion such as welding, the internal surface area of the cooling passage can be remarkably increased, and leakage of fluid from the passage is also prevented. Can be completely prevented.

Therefore, by using the spiral tube of the present invention, it is possible to form a compact cooling passage having a large heat dissipation effect, and it is possible to perform extremely efficient cooling.

[Brief description of drawings]

FIG. 1 is a perspective view showing a cooling spiral tube according to an embodiment.

FIG. 2 is a diagram showing an overall process of a manufacturing method according to an embodiment.

FIG. 3 is a perspective view showing a concavo-convex forming process of the same.

FIG. 4 is a perspective view showing a front bending step.

FIG. 5 is a perspective view showing a crushing process.

FIG. 6 is a perspective view showing a spiral bending process.

7 (a) and 7 (b) are views showing other examples of concavo-convex molding.

FIG. 8 is a sectional view showing another embodiment of the cooling device.

FIG. 9 is a sectional view showing a conventional example.

[Explanation of symbols]

 1 spiral pipe 2 pipe 3 inlet 4 discharge 5 unevenness 6 large diameter part 7 small diameter part 8 cooling passage 9 protrusion 11 unevenness forming process 12 bending process 13 crushing process

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location B29D 31/00 2126-4F F28D 1/047 A F28F 1/08

Claims (6)

[Claims] 1. A flat pipe is spirally wound around an axis orthogonal to the flat direction, and a plurality of irregularities extending from the central axis of the spiral in a radial direction are formed on the surface of the pipe. A spiral tube for cooling, which is characterized in that 2. A concavo-convex forming step of forming a plurality of concavities and convexities along a length direction on a surface of the pipe, a bending step of winding the pipe in a spiral shape, and a direction orthogonal to a spiral traveling direction of the pipe. A method of manufacturing a spiral spiral tube for cooling, comprising a flattening step. 3. The concavo-convex forming step, wherein the entire circumference of the surface of the pipe is enlarged or reduced at a constant pitch to form concavities and convexities, and a bellows tubular pipe as a whole is molded. A method for manufacturing the spiral spiral tube for cooling according to. 4. The method for manufacturing a spiral tube for cooling according to claim 2, wherein in the unevenness forming step, unevenness is formed on the surface of the pipe at unequal pitches. 5. The cooling medium pipe according to claim 1, characterized in that heat medium outlets and inlets are formed at both ends of the cooling spiral pipe so that the heat medium can be circulated inside the spiral pipe. Cooling system. 6. A straight pipe is inserted into the cooling spiral pipe according to claim 1, and the straight pipe and the inner circumference of the spiral pipe surrounding the straight pipe are communicated with each other, and both ends of the straight pipe are connected. The cooling device is characterized in that the heat medium inflow and outflow ports are formed in the respective.