JPH03184617A - Manufacture of cooling fin - Google Patents

Abstract

PURPOSE:To prevent a fold and a rupture by applying pressure being higher to the width direction inside part being near a mandrel than to the width direction outside part being for from the mandrel of a strip, in the direction of the adjacent strip wound round already, and also, in parallel to an axis of the mandrel. CONSTITUTION:An end part 10D of a strip allowed to pass through a guide hole is inserted and held by a strip end part fixing part 24 and fixed to a mandrel 20. Subsequently, a spring 22 is attached between a first guide jig 32 and a guide jig sliding device, and the guide surface of a guide jig assembly 30 is energized toward the strip. When a strip 10A is supplied to the outside peripheral surface of the mandrel 20 through the guide hole, while rotating the mandrel 20, the strip is wound round to the outside peripheral surface of the mandrel 20. Next, the guide jig sliding device is moved in the direction separated from the strip 10 wound already in accordance with the number of turns of the strip. Comparing with the outside part of a strip 10B which is being wound round to the mandrel 20, to the inside part, higher pressure is exerted toward a strip 10C wound already. When the strip of prescribed length is wound round, the strip 10 is cut and removed from the mandrel 20.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to cooling fins, and more particularly to a method for manufacturing cooling fins that are attached to the outer peripheral surface of a pipe with a circular cross section through which fluid flows.

BACKGROUND OF THE INVENTION In order to cool a fluid flowing in a pipe with a circular cross section, it is usually
Cooling fins having a constant pitch are fixed to the outer peripheral surface of the tube. Fixation is usually performed by brazing the cooling fins to the outer circumferential surface of the tube. In order to improve cooling efficiency, it is desirable that there be no gaps between the cooling fins attached to the outer circumferential surface of the tube and the outer circumferential surface of the tube.

The simplest method for manufacturing cooling fins is to wrap the strip material around the outer circumferential surface of the mandrel so that the thickness direction of the strip material makes a certain angle with the axial direction of the mandrel, and then coil the material after winding it to a certain length. This is a method of removing shaped cooling fins from the mandrel.

Conventionally, as shown in Fig. 1O, the wrapping of the band material around the outer circumferential surface of the mandrel is done by fixing one end of the band material to the mandrel using a molding jig 230 that can freely rotate and slide on the mandrel 220. , by rotating the mandrel 220 and wrapping the strip around the mandrel 220. The molding jig 230 has a spiral guide surface 232 with two to three turns at a constant pitch to form a coil shape, and the strip material is rolled along the guide surface 232 of the molding jig 230. You will be guided. Another method is to use a so-called coiling machine to wind the strip around the mandrel.

Problems to be Solved by the Invention In the above-mentioned conventional method, when a thick and narrow strip material is used, the formed coil-shaped cooling fin I is
Although wrinkles and breaks as shown in FIG. 11 do not occur,
The cooling efficiency of the cooling fins decreases. When a thin and wide strip is used to improve the cooling efficiency of cooling fins, when the strip is wrapped around the mandrel, the widthwise part of the strip close to the mandrel is compressed, and the widthwise part far from the mandrel is compressed. is stretched, and wrinkles and breaks occur in the widthwise portion of the strip wound around the mandrel near the mandrel, as shown in FIG.

If a cooling fin is wrinkled or broken, the inner diameter of the part where it is attached to the pipe will no longer be constant, and when the cooling fin is attached to the pipe, a gap will be created between the part and the outer circumferential surface of the pipe, and the cooling fin will be damaged. This will lead to a decrease in cooling efficiency. Moreover, the flow of air between the cooling fins becomes poor, leading to a decrease in cooling efficiency. Furthermore, extra strip material is required.

There may be a need to increase the contact area between the cooling fins and the tubes without causing wrinkles or breaks in the cooling fins, thereby increasing the cooling efficiency of the cooling fins.

In such a case, it is desirable to manufacture cooling fins from an L-shaped member having an L-shaped cross section, but there is no known method for manufacturing cooling fins from an L-shaped member.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for manufacturing cooling fins using thin and wide strips without wrinkles or breaks.

A further object of the present invention is to provide a method for manufacturing cooling fins that have high cooling efficiency and can be easily fixed to pipes.

Another object of the present invention is a method for easily manufacturing cooling fins without wrinkles or breaks using L-shaped members.

Means for Solving the Problem The above object is a method of manufacturing continuous coil-shaped cooling fins by wrapping a strip around the outer peripheral surface of a round mandrel, the thickness direction of the strip being the axis of the mandrel. While wrapping the strip material around the outer circumferential surface of the mandrel so as to be approximately parallel to the direction, a higher pressure is applied to the widthwise inner part of the mandrel near the outer circumferential surface of the adjacent strip material already wound around the mandrel. It is distantly related by a method characterized in that the application is applied in a direction and generally parallel to the axial direction of the mandrel.

In order to wrap the strip material around the outer peripheral surface of the mandrel so that the thickness direction of the strip material is approximately parallel to the axial direction of the mandrel, the thickness of the strip material is The mandrel may be rotated while supplying the band material onto the outer circumferential surface of the mandrel such that one of the two surfaces of the band material parallel to the transverse direction is in contact with the outer peripheral surface of the mandrel. The direction in which the strip material is fed to the mandrel is preferably perpendicular to a plane containing the axis of the mandrel.

In order to apply pressure to the strip being wound around the mandrel in the direction of adjacent strips wound around the mandrel and generally parallel to the axial direction of the mandrel, two sides of the strip (width While one side of the strip is in contact with a guide surface provided so that one side of the strip is adjacent to the outer peripheral surface of the strip that has already been wrapped around the mandrel (plane parallel to the direction), the guide is Pressure can be applied approximately perpendicularly to the surface.

Pressure can be applied to the guide surface by biasing it by suitable elastic means such as springs or rubber.

The widthwise inner part (hereinafter also referred to as the inner part) that is closer to the outer circumferential surface of the mandrel is higher than the widthwise outer part (hereinafter also referred to as the outer part) of the strip material that is being wound around the mandrel that is far from the outer peripheral surface of the mandrel. In order to apply pressure, it is sufficient that the contact pressure between the guide surface and the side surface of the strip in contact with the guide surface is higher in the inner portion of the strip than in the outer portion.

This can be done, for example, by raising the part of the guide surface close to the outer peripheral surface of the mandrel (hereinafter also referred to as the inner part of the guide surface) toward the side of the strip material, or by raising the inner part of the guide surface near the mandrel of the guide surface. This can be achieved by sloping the outer part of the guide surface towards the inner part of the guide surface so that it comes into stronger contact with the side surface of the strip than the part farther from the outer circumferential surface (hereinafter also referred to as the outer part of the guide surface). can.

The cooling fins are obtained by wrapping a predetermined length of band around a mandrel, then stopping the rotation of the mandrel and removing the band wrapped around the mandrel from the mandrel. Such cooling fins are in the form of a continuous coil, with the fins in contact with adjacent fins. Insert the cooling fins into the tube,
The cooling fins are fixed to the tube while applying force to both ends of the cooling fins to provide a constant pitch between the fins. Fixing can be done in a conventional manner, for example by brazing.

Metal materials such as steel, iron, aluminum, and copper are suitable for the material of the band material to be used. The width and thickness of the strip depend on the required cooling efficiency of the cooling fins. The cross section of the strip material can be any quadrilateral cross section such as rectangular or trapezoidal. The edges of the strip may be chamfered.

Furthermore, according to another aspect of the present invention, there is provided a method for manufacturing continuous coil-shaped cooling fins having a constant pitch by winding an L-shaped member around the outer peripheral surface of a round mandrel, the L-shaped member being the mandrel. The L-shaped short side of the L-shaped material is fed to the mandrel at a constant feeding angle through an L-shaped guide hole that extends adjacent to the outer circumferential surface of the mandrel beyond the point of contact with the mandrel. Wrap it around the outer circumferential surface of the guide hole so that the length of the L-shaped short side of the L-shaped member is longer than the length of the L-shaped short side of the L-shaped member.
on the mandrel along a guide surface spaced apart from the long side of the character, adjacent to the outer circumferential surface of the mandrel, extending over at least A method is provided, characterized in that the L-shaped long side portion of a wrapped L-shaped member is guided.

In the following description, the long side of the L character refers to the "1" part of the L character, and the short side part of the L character refers to the "-" part of the L character.

If the L-shaped guide hole does not extend adjacent to the outer circumference of the mandrel beyond the point where the L-shaped member contacts the mandrel, the short L-shaped side of the L-shaped member should be appropriately wrapped around the outer circumference of the mandrel. becomes difficult. The length of the portion of the L-shaped guide hole extending adjacent to the outer peripheral surface of the mandrel beyond the point where the L-shaped member contacts the mandrel shall be 1/12 or more and 1/4 or less of the outer circumference of the mandrel. is desirable, but is not limited to this.

The L-shaped member is fed to the mandrel at a constant feeding angle in order to wrap the L-shaped short side portion of the L-shaped member around the outer peripheral surface of the mandrel. This feeding angle needs to be such that the short side of the L-shape that is being wound around the mandrel does not overlap the short side of the L-shape of the L-shape that has already been wound around the mandrel. Preferably, the feeding angle is approximately equal to the pitch angle of the manufactured coil-shaped cooling fins.

The guide surface must be separated from the long side of the L-shape of the guide hole by an interval equal to or longer than the length of the short side of the L-shape of the L-shape in the direction of the L-shape already wound around the mandrel. There is. This interval is preferably approximately equal to the pitch of the coil-shaped cooling fins.

The guide surface is adjacent to the outer peripheral surface of the mandrel and extends over at least 1/4 of the circumference of the mandrel, preferably not less than X times and not more than 1 time around. If the guide surface does not extend at least two circumferences along the outer peripheral surface of the mandrel, it will be difficult to shape the L-shaped member into cooling fins having a constant pitch.

Extending the guide surface along the outer peripheral surface of the mandrel for more than one circumference will only make machining the guide surface difficult, which is especially noticeable when shaping an L-shaped member into cooling fins with a constant pitch. No effect will occur.

The guide surface intersects a plane perpendicular to the axis of the mandrel at an angle approximately equal to the feeding angle. There is no need to leave a distance between the exit end of the L-shaped guide hole and the part of the guide surface where the L-shaped long side of the L-shaped member starts contacting, or there is a distance of at least X of the outer circumference of the mandrel. You can.

If the gap between the L-shaped short side of the L-shaped guide hole is too narrow, the gap between the L-shaped long side of the L-shaped material wrapped around the mandrel and the L
The angle formed by the short side of the character is an acute angle. If the gap between the L-shaped short sides of the guide hole is too wide, the angle between the L-shaped long side and the L-shaped short side of the L-shaped member wound around the mandrel becomes an obtuse angle. Therefore, the L of the L-shaped member wrapped around the mandrel is
It is preferable that the gap between the short sides of the L-shape of the guide hole can be adjusted so that the angle between the long sides of the L-shape and the short side of the L-shape is approximately a right angle.

The cooling fins are obtained by wrapping an L-shaped member of a certain length around a mandrel, stopping the rotation of the mandrel, and removing the L-shaped member wrapped around the mandrel from the mandrel. Such cooling fins are in the form of a continuous coil with a constant pitch, and the fins are spaced apart from adjacent fins by a constant pitch. Insert the cooling fin into the tube and secure the cooling fin to the tube. Fixing can be done in a conventional manner, for example by brazing. If you want to change the pitch between the fins, both ends of the cooling fins I
By applying this force, you can easily change the pitch.

Suitable materials for the L-shaped member to be used include metal materials such as steel, iron, aluminum, and copper. The width and thickness of the long and short sides of the L-shaped member depend on the required cooling efficiency.

The cross sections of the L-shaped long side portion and the L-shaped short side portion of the L-shaped member can be any quadrilateral cross section, but are preferably rectangular. L-profiles with chamfered edges can also be used.

In the method for manufacturing cooling fins of the present invention using raw milk strip material, while the strip material is being wound around the mandrel, a higher pressure is applied to the inner portion of the strip material than to the outer portion.
The inner part of the strip is not compressed and only the outer part is stretched, so that the strip wrapped around the mandrel does not suffer from wrinkles or breaks.

In the cooling fin manufacturing method of the present invention using an L-shaped member, due to the shape characteristics of the L-shape, wrinkles are unlikely to occur on the long side of the L-shaped member when the L-shaped member is wound around the mandrel. Properly placed guide holes allow the L-shaped short side of the L-shaped member to be wrapped around the outer circumferential surface of the mandrel while largely retaining its original L-shape, and the L-shaped length of the L-shaped member is wrapped along the appropriate guide surface. By guiding the side portions, continuous coil-shaped cooling fins having a constant pitch can be easily manufactured.

EXAMPLE Hereinafter, an example of the method for manufacturing cooling fins of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a plan view of a cooling fin manufacturing apparatus suitable for carrying out the cooling fin manufacturing method using a strip material of the present invention. A mandrel 20 for winding, a band end fixing part 24 provided on the outer peripheral surface of the mandrel 20 for fixing the end 10D of the band, a spring 22, and a guide jig assembly 30 are removed. The guide jig assembly 30 is separated from the first guide jig 32 and the second guide jig 34. The first guide jig 32 and the second guide jig 34 are connected by bolts (not shown). The mandrel 20 is rotatable in the direction of arrow 20' shown in FIG. (not shown).The end of the spring 22 is removably attached to the guide jig slide device.Spring 22
The other end engages a first guide jig 32, and the spring 22 biases the guide jig assembly 30 toward the wound strip 10. In FIG. 1, IOA indicates the strip material being supplied to the outer circumferential surface of the mandrel 20, IOB indicates the strip material that is being wrapped around the outer circumferential surface of the mandrel 20, and IOc indicates the strip material that has already been wound around the mandrel 20 and is adjacent to the strip material 10B. The IOD represents the end of the strip.

Figure 2 shows the guide jig assembly 3 along the line ■-■ in Figure 1.
0 and strip material lO. First guide jig 32
A guide hole 40 for guiding the strip material 10A supplied to the mandrel 20 is provided in the engagement surface of the second guide jig 34, and the cross-sectional shape of the guide hole 40 is the same as the cross section of the strip material 10A. Approximately equal to the shape.

As can be understood from FIG. 2, the strip 10A is attached to the outer periphery of the mandrel 20 such that one of the two surfaces of the strip parallel to the thickness direction of the strip 10A is in contact with the outer peripheral surface of the mandrel 20. It is supplied to the surface through a guide hole 40.

The feeding direction of the strip material 10A is generally orthogonal to a plane containing the axis of the mandrel 20.

FIG. 3 is a diagram of the first guide jig 32 viewed along the line ■■ in FIG. 1. The first guide jig 32 is provided with a center hole 36 through which the mandrel 20 passes. The surface 32A of the first guide jig 32 has a linear recess 42 that forms the guide hole 40, and a radius slightly larger than the sum of the width of the strip lO and the radius of the mandrel following the recess 42. A guide surface 44 is an annular recess concentric with the mandrel 20 and an annular ridge 46 adjacent to the center hole 36 is provided on the inner portion of the guide surface 44 . The depth of the recess 42 and the guide surface 44 relative to the surface 32A of the first guide jig 32 is approximately half the thickness of the strip 10. The height of the raised portion 46 with respect to the guide surface 44 is approximately 0.
It is preferably 0.05 to 0.3 mm.

A recess is provided on the surface of the second guide jig 34 that engages with the first guide jig 32 in a portion facing the recess 42, and together with the recess 42, the guide hole 40 is formed.

An embodiment of a method for manufacturing cooling fins using a strip material of the present invention using a cooling fin manufacturing apparatus 1 will be described with reference to FIGS. 1 to 3.

With the mandrel 20 stationary, the end 10D of the strip passed through the guide hole 40 is inserted into the strip end fixing part 24, and the mandrel 20 is held still.
Fixed to. A spring 22 is mounted between the first guide jig 32 and the guide jig slider to bias the guide surface 44 of the guide jig assembly 30 toward the strip. Next, without rotating the mandrel 20 in the direction of arrow 20', insert the strip 10A into the guide hole 4.
When the strip material is fed to the outer peripheral surface of the mandrel 20 through 0, the strip material is wound around the outer peripheral surface of the mandrel 20. The biasing force of the spring is such that the strip material 10 wound around the mandrel 20 does not wrinkle or break, and the surface of the strip material 10 has a guiding surface 44 and a raised portion 46.
Adjust the biasing force so that no damage occurs due to contact with. The guide jig slide device is moved in a direction away from the already wound-up band lO according to the number of windings of the band.

During the movement, the spring 22 remains biased against the guide surface 44 and, due to the ridge 46, a higher pressure is already applied to the inner part of the strip 10B which is being wound around the mandrel 20 compared to the outer part. It extends toward the strip material 10C. Once a predetermined length of strip material is wrapped around the outer peripheral surface of the mandrel 20, the rotation of the mandrel 20 is stopped, the strip material is cut, and the strip material 10 is removed from the mandrel 20, and the manufacturing of the cooling fin is completed. do.

The method for manufacturing cooling fins using the strip material of the present invention is carried out in such a manner that the end portion 10D of the strip material is fixed to the mandrel 20, and the guide jig assembly 30 and the spring 22 slide with respect to the mandrel 20. As explained above, the guide jig assembly 30 and the spring 2
Of course, the cooling fins can also be manufactured by keeping the fins 2 stationary and sliding the mandrel 20.

FIG. 4 shows a tube 52 with cooling fins 50 attached thereto. After the cooling fins 50 are inserted into the tubes 52, the cooling fins 50 are brazed to the tubes 52.

FIG. 5 shows a cooling fin manufacturing apparatus 1 suitable for implementing the cooling fin manufacturing method using the L-shaped member of the present invention.
00 is shown. The cooling fin manufacturing apparatus 100 includes:
A mandrel 120 for winding the L-shaped member 110, a chuck 124 fixed to the outer peripheral surface of the mandrel 120 to fix the end llOD of the L-shaped member, and a guide jig assembly 13.
Consists of 0. The mandrel 120 is rotatable in the direction of arrow 120'' shown in FIG. In FIG. 5, ll0A is the L-shaped member supplied to the outer peripheral surface of the mandrel 120, 11OC is the L-shaped member already wound around the outer peripheral surface of the mandrel 120, and 110D is the L-shaped member The end of the is shown.

The L-shaped member 11OA is fed to the mandrel 120 at a feeding angle of σ relative to the plane containing the axis of the mandrel 120.

The guide jig assembly 130 includes a first guide jig 140 and a second guide jig 140.
The guide jig 150 and the third guide jig 160 are shown in FIG. The first guide jig 140 and the second guide jig 150 and the first guide jig 140 and the third guide jig 160 are connected by bolts (not shown). Guide jig assembly 130
is disassembled into a first guide jig 140, a second guide jig 150, and a third guide jig 160, and is a perspective view of the first guide jig 140 viewed from the direction of arrow A in FIG. In Figure 6,
FIG. 7 is a perspective view of the second guide jig 150 viewed from the direction of arrow B in FIG. 5, and FIG. 7 is a perspective view of the third guide jig 160 viewed from the direction of arrow C in FIG. It is shown in Figure 8.

As shown in FIG. 6, when the first guide jig 140 is viewed from the direction of arrow A in FIG. 5, the first guide jig 140 is provided with a center hole 142 through which the mandrel 120 passes. One surface of the first guide jig 140 includes a surface 144A that engages with the second guide jig 150 and a surface 1 that engages with the third guide jig 160.
44B, an annular recess 146 concentric with the center hole 142, and a linear recess 148 extending outward from the annular recess 146. The bottom 146A of the annular recess 146 and the bottom 148A of the linear recess 148 are in the same plane.

The bottom portions 146A and 148A form the L-shaped long side portion of the L-shaped guide hole that guides the L-shaped member 110A. The side wall 148B of the linear recess 148 forms the L-shaped short side portion of the L-shaped guide hole that guides the L-shaped member 110A.

The gap between the surface 144A and the surface 144B is the second guide jig 1.
equal to 50 mm thick. The gap between the surface 144A and the bottom 146A of the annular recess 146 and the bottom 148A of the linear recess 148 is approximately half the material thickness of the long side of the L-shaped member. The L-shaped short side of the L-shaped member 110A is the mandrel 1
A virtual plane obtained by extending the side wall 148B of the linear recess 148 contacts the outer circumferential surface of the mandrel 120 so as to contact the outer circumferential surface of the mandrel 120.

As shown in FIG. 7 when the second guide jig 150 is viewed from the direction of arrow B in FIG.
4A, an annular recess 156 that is concentric with the mandrel 120 and has an arc length of approximately 1/4, and a linear recess 156 that extends outward from the annular recess 156. A recess 158 is provided. Annular recess 15
6 and the bottom 158A of the linear recess 158.
and are in the same plane. The bottom portions 156A and 158A are
An L-shaped long side portion of an L-shaped guide hole for guiding the L-shaped member 110A is formed. The gap between the surface 154A and the bottom 156A of the annular recess 156 and the bottom 158A of the linear recess 158 is approximately half the material thickness of the long L-shaped portion of the L-shaped member. Linear recess 148 of first guide jig 140
The lower surface 15 of the second guide jig facing the side wall 148B of
2, along the linear recess 158, the depth is approximately equal to the material thickness of the L-shaped short side portion of the L-shaped member, and the width is approximately equal to the material width of the L-shaped short side portion of the L-shaped member. A recessed portion 152A is provided. The recessed portion 152A forms an L-shaped short side portion of an L-shaped guide hole that guides the L-shaped member 1lOA.

A threaded hole (not shown) is provided in a suitable portion of the second guide jig 150, and a long hole (not shown) provided in a portion of the first guide jig 140 opposite to this hole is provided. ) through the first guide jig 140 and the second guide jig 150.
and fix it. By providing a long hole in the first guide jig 140, the lower surface 152 of the second guide jig 150 and the side wall 148 of the linear recess 148 of the first guide jig 140
The distance between B and B can be adjusted. By this adjustment, the angle formed by the long and short sides of the L-shaped member wound around the mandrel 120 can be adjusted.

As shown in FIG. 8, when the third guide jig 160 is viewed from the direction of arrow C in FIG. A fan-shaped through hole 162A and a guide surface 166 for guiding the L-shaped long side portion of the L-shaped member wound around the mandrel 120 are provided.

The central angle of the fan-shaped through hole 162A is approximately 135°. Therefore, the portion 166A where the exit end of the L-shaped guide hole and the L-shaped long side portion of the L-shaped member start contacting with the guide surface 166.
are separated by 3/8 of the outer circumference of the mandrel 120. The radius of the fan-shaped through hole 162A is approximately equal to the sum of the radius of the mandrel +20 and the width of the L-shaped long side portion of the L-shaped member. The guide surface 166 is formed as a sector-shaped recess and is
They extend approximately five-eighths of the circumference of the mandrel 120 adjacent to the outer circumferential surface of the mandrel 120 . That is, the central angle of the sector-shaped guide surface 166 is about 225°. The radial width of the guide surface 166 is L
It is approximately equal to the width of the L-shaped long side of the shaped material. Back surface 164B of third guide jig 160 that cannot be seen in FIG.
engages with surface 144B of first guide jig 140. Surface 144A of first guide jig 140 and third guide jig 16
0 and the guide surface 166 is approximately equal to the pinch of the cooling coil to be manufactured. The radial edge 166B of the long side of the L-shaped section 166A that initiates contact with the guide surface 166 is preferably rounded or tapered.

Kiting face 166 is inclined with respect to a plane perpendicular to the axis of mandrel 120 by an angle approximately equal to feed angle σ.

A threaded hole (not shown) is provided in an appropriate part of the first guide jig 140, and a hole (not shown) is provided in a part of the third guide jig 160 opposite to this hole. A bolt is passed through to fix the first guide jig 140 and the second guide jig 150.

FIG. 9 is a cross-sectional view of guide jig assembly 130 taken along line ff-ff of FIG. The first guide jig 140 and the second
An L-shaped guide hole 170 for guiding the L-shaped member 110A supplied to the mandrel 120 is provided on the engagement surface of the guide jig 150, and the cross-sectional shape of the guide hole 170 is the same as that of the L-shaped member 110A. approximately equal to the cross-sectional shape of

An embodiment of a method for manufacturing cooling fins using an L-shaped member of the present invention using the cooling fin manufacturing apparatus 100 will be described with reference to FIGS. 5 to 9. FIG.

With the mandrel 120 stationary, the L-shaped guide hole 17
The end portion 110D of the L-shaped member guided along the guide surface 166 through the end portion 110D is clamped by the chuck 124 and fixed to the mandrel 120. Next, while rotating the mandrel 120 in the direction of arrow 120', insert the L-shaped member 110A into the L-shaped guide hole 17.
0 to the outer circumferential surface of the mandrel 120, the L-shaped member is wrapped around the outer circumferential surface of the mandrel 120. Guide hole 17
The L-shaped member exiting the outlet end of the L-shaped member is further wound around the mandrel without being guided by the guide surface 166 on the long side of the L-shaped member. The guide jig slide device is moved in a direction away from the L-shaped member 110c that has already been wound up, depending on the number of windings of the band material. After wrapping the L-shaped member of a predetermined length around the outer peripheral surface of the mandrel 120, the rotation of the mandrel 120 is stopped,
By cutting the L-shaped member and removing the L-shaped member +10 from the mandrel 120, the manufacturing of the L-shaped cooling fin is completed.

A method of manufacturing a cooling fin using the L-shaped member of the present invention will be described with an embodiment in which the end portion 110D of the L-shaped member is fixed to the mandrel 120 and the guide jig assembly 130 slides with respect to the mandrel 120. However, it is of course possible to manufacture cooling fins by keeping the guide jig assembly 130 stationary and sliding the mandrel 120.

To attach an L-shaped cooling fin to a tube, the cooling fin is inserted into the tube and then brazed to the tube.

Using the apparatus shown in FIGS. 1-3, width 8. Using a 5PCC strip with a height of 0.4 mm and an inner diameter of 14.0 mm.
A coil-shaped cooling fin was manufactured. The cross-sectional shape of the guide hole 40 is 8.5 mm x Q.

It was set to 45 mm. The height of the raised portion 46 with respect to the guide surface 44 was set to 0.1 mm. The diameter of the mandrel 20 is 13.95 mm.
, the rotation speed of the mandrel 20 was set to 30 rpm. No wrinkles or breaks were observed in the cooling fin strip produced as described above. The inner diameter of the cooling fins was uniform.

Using the apparatus shown in FIGS. 5 to 9, the width and thickness of the long side of the L shape were 8.0 mm and 0.4 mm, respectively.

The radius and thickness of the short side of the L shape are each 1. omm and 0.4
Using a 5pcc L-shaped member of mm, inner diameter 14, Omm,
Cooling fins with a pitch of 3.2 mm were manufactured. Mandrel 20
The diameter of is 13.95 mm, and the rotation speed of the shaft 20 is 30 Or
It was set as pm. The supply angle σ was set to 3 degrees. The distance between the surface 144A of the first guide jig 140 and the guide surface 166 of the third guide jig 160 was 3 mm. The gap between the L-shaped long sides of the L-shaped guide hole 170 was set to 0.45 mm, and the gap between the L-shaped short sides was set to 0.45 mm. The cooling fin manufactured as described above has a predetermined shape, and the L-shaped long side and L-shaped short side of the L-shaped member of the cooling fin are approximately at right angles, and no wrinkles or breaks are observed. There wasn't. The inner diameter of the cooling fins is uniform.

Effects According to the method for manufacturing cooling fins of the present invention, cooling fins having a uniform inner diameter can be manufactured and can be easily fixed to the outer circumferential surface of a pipe through which fluid flows without any gaps. or,
Materials used can be kept to a minimum.

When manufacturing cooling fins using a strip material, wrinkles or breaks do not occur in the strip material, and the cooling efficiency of the cooling fins can be improved.

When manufacturing cooling fins using L-shaped members, cooling fins having a predetermined shape and pitch can be easily manufactured.

[Brief explanation of drawings]

FIG. 1 is a plan view of a cooling fin manufacturing apparatus suitable for manufacturing cooling fins using the strip material of the present invention. FIG. 2 is a view of the apparatus of FIG. 1 taken along the line ■-■ of FIG. FIG. 3 is a view of the first guide jig viewed along the line ■-■ in FIG. FIG. 4 is a diagram showing cooling fins made from strip material attached to a tube. FIG. 5 is a plan view of a cooling fin manufacturing apparatus suitable for manufacturing cooling fins using the L-shaped member of the present invention. FIG. 6 is a perspective view of the first guide jig used in the apparatus of FIG. 5. FIG. 7 is a perspective view of a second guide jig used in the apparatus of FIG. 5. FIG. 8 is a perspective view of a third guide jig used in the apparatus of FIG. 5. 9 is a cross-sectional view of the guide jig assembly taken along line II-II in FIG. 5; FIG. FIG. 1O is a schematic diagram showing a conventional manufacturing apparatus for cooling fins using a strip material. FIG. 11 is a diagram showing wrinkles and breaks that occur in a cooling fin manufactured by a conventional cooling fin manufacturing apparatus using a strip material. In the figure, l... cooling fin manufacturing device, 10... strip material, 20
... Mandrel, 22... Spring, 30... Guide jig assembly, 32... First guide jig, 34... Second guide jig, 40... Guide hole, 44... Information surface, 46...
- Raised portion, 50... Cooling fin, 52... Tube, 1
00... Cooling fin manufacturing device, 110... L-shaped member, 120... Mandrel, 130... Guide jig assembly,
140... First guide jig, 144A... Surface that engages with the second guide jig, 144B... Surface that engages with the third guide jig, 146... Annular recess, 148... linear recess, 150... second guide jig, 152...
Lower surface, 154A... surface that engages with the first guide, 15
6... Annular recess, 158... Linear recess, 160
...Third guide jig, 162A... Fan-shaped through hole,
166... Guide surface, 170... L-shaped guide hole. 1 other person Figure 2 Figure 9

Claims (1)

[Claims] 1. A method for manufacturing continuous coil-shaped cooling fins by wrapping a strip around the outer peripheral surface of a round mandrel, wherein the thickness direction of the strip is approximately parallel to the axial direction of the mandrel. While wrapping the strip material around the outer circumferential surface of the mandrel, a higher pressure is applied to the widthwise inner portion of the strip material closer to the outer circumferential surface of the mandrel than to the widthwise outer portion far from the outer circumferential surface of the mandrel. A method characterized in that the application is directed in the direction of adjacent strips wound on the mandrel and generally parallel to the axial direction of the mandrel. 2. A method of manufacturing continuous coil-shaped cooling fins with a constant pitch by wrapping an L-shaped member around the outer circumferential surface of a round mandrel, in which the L-shaped member wraps around the outer circumference of the mandrel beyond the point where the L-shaped member contacts the mandrel. The L-shaped material is fed to the mandrel at a constant feeding angle through the L-shaped guide hole extending adjacent to the surface, and the L-shaped short side of the L-shaped material is wrapped around the outer peripheral surface of the mandrel. The length of the guide hole is longer than the length of the short side of the L shape.
along a guide surface spaced apart from the long side of the character and adjacent to the outer circumferential surface of the mandrel, extending around at least one-fourth of the circumference of the mandrel and intersecting the axis of the mandrel at an angle substantially equal to the feeding angle; A method characterized by guiding the long side of an L-shaped member wrapped around a mandrel.