JPH086846B2 - Fitting method of fitting member to pipe material - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe material applied to the production of pressure-resistant pipes having reinforcing members inside such as used in platen rolls for printers, and multiple pipes for heat exchangers. The present invention relates to a method of fitting and fixing a fitting member.

2. Description of the Related Art Conventional Problems and Problems A press-fitting method is well known as one of fixing means for fixing another metal member in a pipe material made of a metal material such as an aluminum material in an inserted state. In the press-fitting method, the fitting member is forcibly fitted into the pipe material so as to join the two together, but since the press-fitting is performed by utilizing the elastic limit of the material itself, the pipe material and the press-fitting member are There is a problem that very strict dimensional accuracy is required between the two, and a sufficient fixing force is not always obtained in many cases. In particular, it is difficult to press-fit and fix a long object, and there is no compatibility in the case where a fitting member of a corresponding length is fixed to the inside in a fitted state over the entire length of the pipe material.

On the other hand, as another fitting and fixing method, there is also known a method in which a fitting member inserted loosely in advance in the pipe material is brought into close contact with the inner peripheral surface of the pipe material and fixed by the operation of contraction or expansion by drawing. However, especially in applications where external forces such as vibrations are applied, there is a lack of an effect of retaining a good fixing force for a long period of time, and it is not always suitable for use.

Under the above background, the present invention can firmly insert and fix the fitting member to the pipe material even in a long object,
Moreover, it is an object of the present invention to provide a method of fitting and fixing a pipe member and a fitting member, which can be combined with each other relatively easily and can improve productivity.

Means for Solving the Problems The present invention relates to either a metallic pipe member or a metallic fitting member to be fixed in an inserted state in the metallic pipe member,
A plurality of elastically deformable portions are integrally formed that have an arcuate curved portion in at least a part of the cross section, and can elastically deform the curved portion to change the apparent inner diameter or outer diameter of the entire cross section. After loosely inserting the mating member into the pipe material, the pipe material is reduced in diameter by drawing or the fitting member is expanded to cause elastic deformation in the elastically deformed portion, and the elastic restoring force of the mating member causes mutual elastic deformation with the mating member. A gist of a method of fitting and fixing a fitting member to a pipe material, characterized in that the pipe material and the fitting member are integrally coupled by contacting with each other.

Example Hereinafter, this will be described more specifically based on the illustrated example.

(Embodiment 1) FIGS. 1 to 5 show a first embodiment.

In this embodiment, in the case of manufacturing a reinforcing plate for a platen roll for printers and other applications where pressure resistance is required, inside the pipe material (1) made of aluminum or aluminum alloy, the aluminum material or Fitting member made of other materials for reinforcement (2)
Is intended to be fixed in the inserted state over the entire length.

The fitting member (2) is a tubular or solid rod-shaped shaft portion (4).
On the outer peripheral surface thereof, there are provided elastic ribs (3) as a plurality of elastically deforming portions protruding outward in a radial arrangement. As shown in FIG. 2, each of the ribs (3) has an arcuate shape whose cross section is curved in a predetermined direction, and elastic deformation can be relatively easily generated in the radial direction of the fitting member according to the curvature. Has been made. Moreover, the ribs (3) have an apparent outer diameter connecting their free ends slightly smaller than the inner diameter of the pipe material (1).

Therefore, when the fitting member (2) is fitted and fixed to the pipe material (1), the fitting member (2) is first loosened in the pipe material (1) as shown in FIG. Insert into the state. Then, the pipe material (1) is subjected to a drawing process using a drawing jig (5) as shown in FIG.
Reduce the pipe diameter. Here, in this contracting operation, it is assumed that the inner diameter of the pipe material (1) is reduced to a range where the inner diameter is smaller than the apparent outer diameter of the fitting member (2). Then
Due to this contracted tube, the fitting member (2) receives a tightening force from the surroundings, and the elastic rib (3) is flexibly elastically deformed in the radial direction as shown in FIG. Each of the tips presses against the inner surface of the pipe material (1) by its elastic restoring force. Therefore, with this pressure contact force, the fitting member (2) is firmly fixed in the inserted state inside the pipe material (1) over its entire length as shown in FIG.

FIG. 6 shows a modified example of the elastic rib. The rib (3 ') has a semi-arcuate curved portion (3a) at the middle portion in the height direction.
With this, it is possible to easily cause buckling-like elastic deformation in the radial direction by the portion. In addition to the above, the shape of the elastic rib can be arbitrarily changed within a range in which elastic deformation in the radial direction can be easily caused.

(Embodiment 2) In this embodiment, as shown in FIGS. 7 and 8, elastic ribs (13) are provided on the inner surface of the pipe material (11) side, and a center portion surrounded by the rib group is separately provided. A thin tube as a fitting member (12) is fitted and fixed. In the case of this embodiment, the apparent inner diameter connecting the tips of the elastic ribs (13) group of the pipe material (11) is slightly larger than the outer diameter of the fitting member (12).

Thus, as shown in FIG. 7, the fitting and fixing of both members is performed by first fitting the thin tubular fitting member (12) to the rib group (13) of the pipe material (11).
After being inserted in a loose state, the fitting member (12) is subjected to a known pipe expansion drawing process to enlarge its diameter. This expansion is performed within a range that can cause elastic deformation of the elastic ribs (13) in the radial direction, so that the elastic restoring force of the ribs (13) causes the elastic member (13) to move around the fitting member (12) as shown in FIG. It is a thing that tightens it tightly and fixes it.

(Embodiment 3) The embodiment shown in FIG. 9 is one in which the present invention is applied to the production of a multi-tube used as a tube material for a heat exchanger.

As its constituent member, an outer pipe (21) as a pipe material
And an intermediate pipe (22) as a first fitting member fitted inside thereof and an inner pipe (23) as a second fitting member fitted and fixed inside thereof. Then, arc-shaped elastic ribs (3) and (3) are provided on the inner and outer peripheral surfaces of the intermediate pipe (22) extruded as a double pipe, respectively, as in the first and second embodiments. There is. Then, first, the outer pipe (21) and the intermediate pipe (22) are loosely fitted, the outer pipe (21) is reduced in diameter to fix the two pipes to each other, and then the intermediate pipe (22) The inner pipe (23) is loosely inserted in the inner pipe (23), and the inner pipe (23) is expanded and fixed to the intermediate pipe (22) so that the inner pipe (23) and the intermediate pipe (22) are integrally connected to each other. Of course, the inner pipe (23) and the intermediate pipe (22) may be joined first, and then the outer pipe (21) may be fixed. The fitting assembly of this embodiment is a multi-tube having a large number of hollow portions (6) parallel to the axial direction inside, and a tube for a heat exchanger that allows a heat exchange medium such as a refrigerant to flow through the hollow portions (6). It can be suitably used as a material.

(Embodiment 4) As shown in FIG. 10, the fitting member (32) has a narrow press contact portion (33) having an arcuate cross section which is continuous in the axial direction and is parallel to four points on the outer peripheral surface of the fitting member (32). It is provided in the shape of
It is supposed that elastically flexible bridge portions (34) (34) having an arcuate cross-section curved inward in a manner of connecting them between the adjacent pressure contact portions (33) (33) are provided. Thus, the fitting member (32) is such that the apparent diameter of the outer circumferential circle connecting the press contact portions (33) is smaller than the inner diameter of the pipe material (31), and the fitting member (32) is loosely inserted into the pipe material after being inserted. , By reducing the diameter of the pipe material (31), the bridge part (3
4) Inward elastic deformation is caused in 4), and the elastic restoring force presses the pressure contact portion (33) against the inner surface of the pipe material (31) to obtain the fixed state of the fitting member. This assembly can be used, for example, as in Example 3 as a porous tube material for a heat exchanger.

In the modified example shown in FIG. 11, the pressure contact portion (33) is circumferentially 3
Individually provided, and the bridge portions (34) connect between them. Others are the same as in the case of FIG.

EFFECTS OF THE INVENTION According to the present invention, either one of the fitting member to be fixed in the pipe member in the inserted state and the pipe member is elastically deformed in the radial direction to cause a substantial apparent outer diameter or An elastic rib having an arcuate curved portion is formed on at least a part of the cross-section of an elastic rib or a bridge portion whose inner diameter can be reduced or expanded, and the elastic force of the elastic deformed portion is used in a fitted state to both sides. Since it is designed to achieve mutual fixation of the members, there is a large allowable range of relative dimensional error between the pipe material and the fitting member, and even if their accuracy is a little poor, fitting and fixing of both members can be done without any problems. Moreover, after fitting and fixing, the spring back effect of the elastically deformed portion can realize a sufficiently strong mutual fixing state between the pipe member and the fitting member, which may result in incomplete fixing due to poor dimensional accuracy. There is no.

Further, since the fitting member having an elastically deformable portion on one of them and the pipe material are inserted loosely in advance, the pipes are expanded or contracted to obtain a combined state of the two.
There is little difficulty in working, and even long products can be fitted and assembled without any problems, which is also advantageous in terms of productivity. Therefore, it is possible to easily manufacture a multi-pipe having a long and complicated cross-sectional structure, and the pipe material and the fitting member are integrally combined with each other by using different kinds of metal materials. It is also possible to cope with the manufacturing of composite pipe materials conveniently.

[Brief description of drawings]

1 to 5 show a first embodiment of the present invention. FIG. 1 is a perspective view of a pipe material and a fitting member before being inserted,
2 is a cross-sectional view of the state after insertion, FIG. 3 is a cross-sectional view showing a state of reducing the diameter of the pipe material by drawing, and FIG. 4 is a cross-sectional view of the assembly after the diameter reduction fixing of the pipe material. FIG. 5 is an enlarged sectional view of an elastic rib formed on the fitting member, and FIG. 6 is a sectional view of a modified example of the elastic rib. FIGS. 7 and 8 show a second embodiment of the present invention. FIG. 7 is a cross-sectional view of the fitting member inserted in the pipe material, and FIG. 8 is a view after the fitting member is expanded and fixed. It is a cross-sectional view of a state. FIG. 9 is a cross sectional view of the third embodiment of the present invention, and FIG. 10 is a cross sectional view of the fourth embodiment of the same.
FIG. 11 is a cross-sectional view of the modified example. (1) (11) (21) (31) ... Pipe material, (2) (12) ... Fitting member, (3) (3 ') (13) ... Elastic rib (elastically deformable portion), (22) ... 1 Fitting material (intermediate pipe), (23)
... Second fitting member (inner pipe), (33) ... Pressing contact part, (34)
... Bridge section (elastically deformable section).

Claims (3)

[Claims] 1. A curved pipe having an arc-shaped curved portion in at least a part of a cross section of one of a metallic pipe member and a metallic fitting member to be fixed to the metallic pipe member in an inserted state. A plurality of elastically deformable parts that can change the apparent inner diameter or outer diameter of the entire cross section by elastic deformation of the part are integrally formed, and after the fitting member is loosely inserted into the pipe material, the pipe material is contracted by drawing process. The pipe member and the fitting member are integrally connected by elastically deforming the elastically deforming portion by making the diameter or expanding the fitting member and elastically contacting each other with the elastic restoring force. Characterized by
A method of fitting and fixing the fitting member to the pipe material. 2. The elastically deformable portion is composed of a plurality of elastic ribs having an arcuate cross-section and protruding in a radial arrangement on the inner peripheral surface of the pipe member or the outer peripheral surface of the fitting member and being flexible in the radial direction. A method for fitting and fixing a fitting member to a pipe material according to claim 1. 3. The elastically deformable portion is formed inward in the cross-section of the fitting member by connecting adjacent ones of a plurality of axially long press contact portions formed at predetermined intervals in the circumferential direction. The method for fitting and fixing a fitting member to a pipe member according to claim 1, which comprises a plurality of flexible bridge portions curved in an arc shape in cross section.