CN212643820U

CN212643820U - Buckling device for connecting hollow pipe

Info

Publication number: CN212643820U
Application number: CN202020803978.2U
Authority: CN
Inventors: 王树成; 刘志威; 王龙
Original assignee: Contitech Fluid Technology Changchun Co ltd
Current assignee: Contitech Fluid Technology Changchun Co ltd
Priority date: 2020-05-14
Filing date: 2020-05-14
Publication date: 2021-03-02
Anticipated expiration: 2030-05-14

Abstract

The utility model relates to a withhold device for connecting hollow tube, include: an insert comprising a connecting section connecting the first hollow tube and an inserting section inserting the second hollow tube, the inserting section being provided with a first annular protrusion protruding radially outward, the connecting section being provided with a boss; a sleeve which is provided with a second annular projection projecting radially inwards, the first annular projection and the second annular projection being arranged in a staggered manner when the sleeve is mounted on the insertion section, the second hollow tube being accommodated and pressed between the first annular projection and the second annular projection, the connection section of the sleeve to the insert having a circumferential hollow bulge which bears axially against the projection of the insert and accommodates the tube of the second hollow tube radially with an opening. Through adjusting the insert diameter, can effectively connect the great air conditioner pipe of internal diameter, through axial space and atress difference between sleeve and the insert, lead to the body after the withholding difficult impaired under high temperature.

Description

Buckling device for connecting hollow pipe

Technical Field

The utility model relates to a withhold device for connecting hollow tube, especially be arranged in connecting tubular metal resonator and air conditioner pipe in the car.

Background

For connecting air conditioning pipes of automobiles, various buckling devices are known in the prior art for tightly connecting air conditioning pipes and metal pipes, see CN 106015780B, CN 109630771 a and the like. However, the air-conditioning pipe buckling device is only generally suitable for the air-conditioning pipe with the maximum inner diameter of about 19 mm. For larger inner diameter air conditioning ducts generally not applicable.

The air conditioning pipe may be made of different materials, such as PTFE (polytetrafluoroethylene, commonly known as teflon) steel wire woven pipe, multilayer composite rubber pipe, and the like. These air conditioning ducts may expand in high temperature environments, causing the air conditioning ducts to be damaged or even broken.

Therefore, there is a need for an improved crimping device for air conditioning ducts that addresses the above-mentioned problems. In particular, in some cases, such as in the arabian region, the challenge of larger inner diameter and higher working temperature of the air conditioning pipe of the passenger car is faced at the same time, and a buckling device which meets the two challenges needs to be developed.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a withhold device for connecting the hollow tube, especially be arranged in connecting tubular metal resonator and the air conditioner pipe in the car, this withhold device can effectively connect the great air conditioner pipe of internal diameter to the body is difficult impaired under high temperature.

This purpose is through according to the utility model discloses a withhold device for connecting hollow tube realizes, should withhold the device and include:

-an insert comprising a connecting section connecting the first hollow tube and an insertion section inserting the second hollow tube, the insertion section of the insert being provided with a first annular protrusion protruding radially outwards, the insert being provided with a boss at the connecting section;

a sleeve provided with a second annular projection projecting radially inwards,

wherein, when the sleeve is mounted on the insertion section of the insert, the first annular protrusion and the second annular protrusion are arranged in a staggered mode, and the second hollow tube is accommodated and compressed between the first annular protrusion and the second annular protrusion. The sleeve, the second hollow tube and the insert are tightly pressed together by the radially inward extrusion of the buckling die surrounding the sleeve.

Here, preferably, an outer diameter of the first annular protrusion is larger than an inner diameter of the second hollow tube and smaller than an outer diameter of the second hollow tube; the inner diameter of the second annular protrusion is smaller than the outer diameter of the second hollow pipe and larger than the inner diameter of the second hollow pipe. The first and second annular projections may each have a different longitudinal cross-sectional shape, such as triangular, square, hook-shaped, etc., and preferably have rounded corners.

The important improvement of the invention consists in that the sleeve has a circumferential hollow bulge towards the connecting section of the insert, the axial direction of which bears against the boss of the insert and radially accommodates the body of the second hollow tube with the opening. By means of the hollow elevation, a large annular space is formed between the end of the second hollow tube and the inner wall of the sleeve, into which annular space the material of the second hollow tube can deform during the crimping process, whereby on the one hand a space is left for the tube to flow and on the other hand a pull-off damping is formed there after crimping.

Preferably, the maximum inner diameter of the hollow bulge of the sleeve is larger than the outer diameter of the boss of the insert. Therefore, the space into which the pipe can deform is further enlarged, and the pull-out damping is further ensured.

Preferably, the end of the sleeve facing away from the hollow elevation is shaped as a radially outwardly, for example flared, expansion section. More preferably, the wall thickness of the expanded section of the sleeve is uniform. Thereby, on the one hand, the installation of the second hollow tube is facilitated; on the other hand, in the buckling and pressing process, the expanded horn mouth leaves an extrusion space for the material of the second hollow tube, so that the second hollow tube is prevented from being crushed and even broken. Furthermore, during use after crimping, the diameter of the second hollow tube may expand, and the flare provides cushioning for it, preventing breakage.

Preferably, the first annular protrusion is formed in a cone shape with the largest diameter towards the connecting section and the cone angle (i.e. the angle of the conical outer surface with the longitudinal direction) is between 8 ° and 12 °. The first conical annular protrusion of the angular range can be tightly matched with the second annular protrusion on the sleeve after being buckled, so that the second hollow pipe can be sufficiently grasped.

In principle, the outer circumferential surface of the insertion section can be provided with a plurality of first annular projections. The inner circumferential surface of the sleeve may also be provided with a plurality of second annular projections. However, as the number of projections increases, the axial length of the insertion section and the sleeve increases, resulting in an increase in the component construction space. Thus, the smaller the number of projections, the better the spacing between the second annular projections of the sleeve and the first annular projections of the insert, while ensuring a tight grip.

Preferably, the outer circumferential surface of the insertion section is provided with two axially spaced first annular projections, preferably two conical and co-directional first annular projections. Preferably, one of the first annular projections defines an insertion end of the insert, and the other first annular projection is adjacent to and spaced from the boss.

Preferably, the inner circumferential surface of the sleeve, after crimping, has two axially spaced second annular projections, which are arranged staggered with respect to the two first annular projections on the insertion section. Preferably, the second annular projection is flat and one end of the second annular projection is radially aligned with the largest diameter end face of the first annular projection. The second hollow tube is tightly grasped between the sleeve and the insert by mating and crimping the two first annular projections on the insert and the two second annular projections on the sleeve with one another. Wherein, the circumferential diameters of the two second annular protrusions can be the same or different.

Preferably, one of the second annular projections on the sleeve adjacent the hollow protuberance has a smaller circumferential diameter than the other of the second annular projections facing away from the hollow protuberance. Thus, the radial clearance between the second annular projection and the insert adjacent the hollow protuberance is relatively small, and the tubular body material of the second hollow tube can be squeezed more into the adjacent hollow protuberance; the radial gap between the second annular projection facing away from the hollow elevation, i.e. towards the expansion section, and the insert is relatively large, so that the second hollow tube is deformed here not too much, with a natural transition to the expansion section.

In principle, the hollow bulge can be shaped in different ways, for example, triangular, square, trapezoidal, circular in longitudinal section, and can provide good damping if the highest part of the bulge extends radially beyond the projection. Preferably, the hollow bulge is formed in a conical shape with a maximum diameter facing the connecting section of the insert and is rounded off at the maximum diameter.

Preferably, the conical first annular projection of the insert is shaped rounded at the maximum outer diameter. Thereby avoiding puncturing the hollow tube made of rubber material, and simultaneously the rubber can flow after being buckled and pressed, and the rounding part is filled up, thereby not influencing the gripping force.

Preferably, the insertion section of the insert is axially longer than the sleeve. Therefore, the insertion section of the insertion piece axially exceeds the sleeve at the end part of the sleeve, and the phenomenon that the material of the second hollow pipe flows radially inwards to influence the inner hole passing rate of the pipe during buckling and even the inner wall of the pipe is damaged due to overlarge extrusion amount can be avoided.

Preferably, the sleeve has a radial bore in the hollow elevation. The drill hole is used as an observation hole for observing and judging whether the second hollow pipe is inserted into a required position.

The first hollow pipe to be connected is a hard pipe, and the second hollow pipe is a hose.

Preferably, the second hollow tube is a rubber tube. The material of the rubber tube enters the inner cavity of the hollow bulge part after being buckled and pressed. Typically, the second hollow tube is an automotive air conditioning tube.

Preferably, the first hollow tube is a metal tube, and the insert and the first hollow tube are connected by welding or integrally formed.

Preferably, the insert and the sleeve are constructed of steel. Among them, the sleeve is generally formed by press molding using a steel plate, so that the wall thickness of the sleeve is uniform. Depending on the material of the second hollow tube to be connected, the sleeve may not be formed with the second annular protrusion before the die crimping, for example, when the second hollow tube is a rubber tube, in which case the sleeve is formed with the second annular protrusion at a predetermined position during the die pressing process to cooperate with the first annular protrusion of the insert for crimping.

Preferably, the crimping device according to the invention is free of adhesive. Sufficient tightness can be achieved only by mechanical crimping.

It should be noted that, as used herein, reference to "radial" means a direction from the central axis of the pipe to the circumferential surface of the pipe, and "axial" or "longitudinal" means a direction along or parallel to the central axis of the pipe. "radial" and "axial" are perpendicular to each other in the plane of the drawing.

The utility model has the advantages that:

the shape design of the sleeve fully considers the problems of reliable fixation of the sleeve and the insert and buckling of the sleeve, the air-conditioning pipe and the insert, and is convenient for simultaneously completing fixation of the sleeve and the insert and connection of the sleeve, the air-conditioning pipe and the insert through one-time buckling. The provision of the insertion section of the insert enables matching of large-diameter air conditioning tubes. The hollow bulge at the end of the sleeve provides an extrusion space for the pipe made of rubber materials, and is favorable for avoiding pulling off. The gap and the stress between the inside of the sleeve and the insert are different, and particularly the design of the horn mouth at the tail part ensures that the buckling edge of the air-conditioning pipe cannot be damaged or even broken due to excessive expansion, so that the use function of the air-conditioning pipe is prevented from being influenced by a high-temperature environment. In addition, the whole buckling and pressing process is completed mechanically without any adhesive, so that the method is more convenient and environment-friendly.

Drawings

Preferred embodiments of the invention are explained in detail below with the aid of the figures. Showing:

figure 1 shows in a side view a crimping device according to the invention, after crimping;

fig. 2 shows a crimping device according to the invention before crimping in an exploded view;

fig. 3 shows a crimping device according to the invention in a perspective view and in a partially sectioned view, after crimping has been completed.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the following description is given for clarity and completeness with reference to the embodiments, and it is obvious that the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Fig. 1 and 3 show a crimping device according to the invention in a side view and in a perspective sectional view, respectively, with the crimping being completed, and fig. 2 shows an exploded view of the crimping device according to the invention before crimping. The crimping device comprises an insert 1 and a sleeve 2 for a first hollow tube 1 and a second hollow tube 4. Wherein, the first hollow tube 3 is a metal tube, and the second hollow tube 4 is a rubber tube. Wherein the insert 1 and the sleeve 2 are made of steel, and the inner and outer surfaces are smooth and are electro-galvanized.

One side of the insert 1 is fixedly connected to the metal tube by welding, from which connecting side the insert 1 has, in order, a projection 111 and an insert section 12. The outer diameter of the circumferential surface of the boss 111 is 29mm, and the outer diameter of the circumferential surface of the insertion section 12 is 22 mm. The outer circumferential surface of the insertion section 12 is provided circumferentially with two conical, radially outwardly projecting first

annular projections

1211, 1212 which are axially spaced apart and each have an outer diameter which increases towards the boss 111, i.e. are arranged in the same direction. Wherein one first annular projection 1211 is adjacent to and spaced from the boss 111 by a flat surface, two first

annular projections

1211, 1212 are also spaced by a flat surface, and one end of the other first annular projection 1212 having the smallest outer diameter is formed as the tip of the insert 1 into which the rubber tube is inserted. The two first annular projections each have a taper angle of 10 ° and are rounded at the maximum outer diameter.

In this embodiment, a steel plate punch forming is used to obtain a semi-finished product (i.e. not yet crimped, see fig. 2) of the sleeve 2, which is a cylinder with a flat surface and a uniform wall thickness. The cylinder is bent radially inwardly at one end to form a surrounding recessed end 24 and at the opposite end is formed as a flared radially outwardly flared section 23. Wherein the concave end 24 has an inner diameter of 23.8 mm. Optionally, the sleeve 2 has a bore (not shown) in its circumferential surface adjacent the recessed end 24 as a viewing aperture.

During assembly, the sleeve 2 is first inserted with the female end 24 from the insertion section 12 into the insert 1 until the female end 24 abuts against the end face of the projection 111. An encircling gap is enclosed between the inner surface of the sleeve 2 and the outer surface of the insertion section 12 of the insert 1. Subsequently, a rubber tube is inserted into this gap until it abuts against the side of the recessed end 24, which can be observed and judged through the aforementioned observation hole. The axial length of the insertion section 12 of the insert 1 is 36mm and the axial length of the sleeve 2 is 35mm, so that, after the sleeve 2 is fitted over the insert 1 and stopped on the end face of the boss 111, the end of the insertion section of the insert 1 protrudes slightly beyond the end of the expansion section of the sleeve 2 (see fig. 3).

After the rubber tube has been inserted between the sleeve 2 and the insert 1, an extrusion die (not shown) is used outside the sleeve 2, which extrusion die is assembled from 8-segment dies into a cylinder, the inner surface of which is provided with two annularly spaced, radially inwardly directed projections, the radially inner surfaces of which projections are flat. The extrusion die surrounds the radially outer portion of the sleeve 2 and exerts a radially inward pressure thereon. Two flat-bottomed second

annular protrusions

211, 212 axially spaced and radially inwardly protruding are circumferentially molded on the cylindrical surface of the sleeve 2 by two of said protrusions on the die, wherein one side of one of the second annular protrusions 211 radially corresponds to the maximum diameter end of the first annular protrusion 1211, and one side of the other second annular protrusion 212 radially corresponds to the maximum diameter end of the other first annular protrusion 1212, so as to be axially staggered and snap-fitted with each other. Meanwhile, a hollow bulge 22 is formed on the side of the sleeve 2 near the concave end 24, which increases in diameter toward the boss 111. The hollow bulge 22 projects radially beyond the projection 111 of the insert 1 at the highest point, i.e. the maximum inner diameter of the hollow bulge 22 is greater than the outer diameter of the projection 111, and the hollow bulge 22 is rounded at the maximum inner and outer diameters. The rubber tube is affected by the extrusion, and the material deforms and flows and extrudes into the lumen of the hollow bulge 22.

The two second annular protrusions of the sleeve 2 have different circumferential outer diameters, the corresponding circumferential inner diameters also being different, wherein the circumferential diameter (outer diameter and inner diameter) of the second annular protrusion 212 near the flared section is larger than the circumferential diameter (outer diameter and inner diameter) of the second annular protrusion 211 near the hollow elevations. In this embodiment, the diameter of the cylindrical outer surface of the sleeve 2 before the swaging of the die is 38.5mm, the diameter of the circumferential outer surface of the second annular protrusion 211 formed after the extrusion of the die adjacent to the hollow ridge becomes 29.8mm, and the diameter of the circumferential outer surface of the second annular protrusion 212 adjacent to the expanding section becomes 30.5 mm. In this compressed condition of the outer diameter, the insert 1 is very strong against deformation, whereby a very large buckling force can be effectively created between the insert 1 and the rubber tube and the sleeve 2. No adhesive is required in the whole crimping device.

Additionally, during extrusion, the outer surface material of the sleeve 2 may be partially deformed into the gaps between the respective flap molds, thereby longitudinally forming projecting ribs circumferentially spaced from one another on the outer surface.

It is to be understood that the above embodiments are merely exemplary embodiments that have been employed to illustrate the principles of the present invention, and that the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.

Description of the reference numerals

1 insert piece

12 insertion section

111 boss

1211. 1212 first annular projection

2 sleeve

22 hollow bulge

23 expansion section

24 concave end

211. 212 second annular projection

3 the first hollow pipe

4 second hollow pipe

Claims

1. A crimping device for connecting hollow tubes, the crimping device comprising:

an insert (1) comprising a connecting section connecting a first hollow tube (3) and an insertion section (12) inserting a second hollow tube (4), the insertion section (12) being provided with a first annular protrusion (1211, 1212) protruding radially outwards, the insert (1) being provided with a boss (111) at the connecting section;

a sleeve (2), said sleeve (2) being provided with a second annular projection (211, 212) projecting radially inwards;

wherein, when the sleeve (2) is mounted on the insertion section (12), the first and second annular projections are staggered, the second hollow tube (4) being housed compressed between them;

characterized in that the connecting section of the sleeve (2) facing the insert (1) has a circumferential hollow bulge (22) which bears axially against the projection (111) of the insert (1) and receives the tubular body of the second hollow tube (4) radially in an open manner.

2. Crimping device according to claim 1, characterized in that the maximum inner diameter of the hollow elevations (22) of the sleeve (2) is larger than the outer diameter of the bosses (111).

3. Crimping device according to claim 1, characterized in that the end of the sleeve (2) facing away from the hollow elevation (22) is shaped as a radially outwardly expanding section (23).

4. Crimping device according to one of claims 1 to 3, characterized in that the first annular projection (1211, 1212) is formed in a conical shape with a maximum diameter towards the connection section and a conical angle of between 8 ° and 12 °.

5. Crimping device according to claim 4, characterized in that the outer circumferential surface of the insertion section (12) is provided with two axially spaced and co-directed conical first annular projections (1211, 1212).

6. Crimping device according to claim 5, characterized in that the inner circumferential surface of the sleeve (2) has, after crimping, two axially spaced second annular projections (211, 212) which are arranged staggered with respect to the two first annular projections (1211, 1212) on the insertion section (12).

7. Crimping device according to claim 6, characterized in that on the sleeve (2) one second annular projection (211) close to the hollow elevation (22) has a smaller circumferential diameter than the other second annular projection (212) facing away from the hollow elevation (22).

8. Crimping device according to one of claims 1 to 3, characterized in that the hollow elevation (22) is tapered with a maximum diameter towards the connecting section of the insert (1) and is shaped rounded at the maximum diameter.

9. Crimping device according to claim 4, characterized in that the first annular projection (1211, 1212) is shaped rounded at the maximum outer diameter.

10. Crimping device according to one of claims 1 to 3, characterized in that the insertion section (12) is axially longer than the sleeve (2).

11. Crimping device according to one of claims 1 to 3, characterized in that the sleeve (2) has a radial bore on the hollow elevation (22).

12. Crimping device according to one of claims 1 to 3, characterized in that the second hollow tube (4) is a rubber tube.

13. Crimping device according to one of claims 1 to 3, characterized in that the first hollow tube (3) is a metal tube, the insert (1) and the first hollow tube (3) being connected by welding or being integrally formed.

14. Crimping device according to one of claims 1 to 3, characterized in that the insert (1) and the sleeve (2) consist of steel.