Joining method, and device for such

Abstract

A method and a device for obtaining a joint between two surfaces of two parts that have a simple curvature are proposed in which a mandrel is placed below the first surface, which contains a moving stamp in its interior. A template is placed above the second surface, which has a deep drawing opening. The stamp is moved along the surface normals of the two surfaces, such that material forming the two surfaces is forced into the deep drawing opening, wherein the deep drawn and compressed portion of the first surface engages behind the remaining part of the second surface to obtain a form-fit connection between the two surfaces. The stamp blocks a channel inside the mandrel until pressure from a medium therein causes the stamp to move.

Claims

1. A joining method comprising the following steps: positioning a first part and a second part, with the second part positioned above the first part, the first part has a first surface and the second part has a second surface, the first part and the second part each have simple curvatures, positioning a mandrel below the first surface, the mandrel contains a moving stamp in its interior, positioning a template above the second surface, the template has a deep drawing opening, moving the stamp along a surface that is aligned normal to at least one of the first or second surfaces, such that material of the respective first and second surfaces is forced into the deep drawing opening, wherein the stamp blocks a channel inside the mandrel until a hydraulic pressure exerted by a fluid against a surface of the stamp is large enough to cause the stamp to move, wherein in order to obtain a form-fit connection between the first and second surfaces a deep drawn portion of the first surface engages behind portions of the second surface that surround a deep drawn portion of the second surface, wherein the template is disposed such that the template does not move in relation to the stamp, and the size of the deep drawing opening remains constant, the stamp is returned to its starting position, and the template and mandrel are removed.

2. The method according to claim 1, wherein a joint is obtained by at least partially deforming the material forming the first and second surfaces which ends up at least partially above and/or outside the first and second surfaces.

3. The method according to claim 1, wherein the stamp moves substantially at a right angle with respect to at least one of the first surface or the second surface.

4. The method according to claim 1, wherein the first part is a closed tube, and the first surface is formed by at least part of the wall of the tube, wherein the tube and the mandrel are positioned such that their respective central axes coincide or are aligned such that their respective central axes have an angular deviation of 10 or less.

5. A joining method comprising the following steps: positioning a first part and a second part, with the second part positioned above the first part, the first part has a first surface and the second part has a second surface, the first part and the second part each have simple curvatures, positioning a mandrel below the first surface, the mandrel contains a moving stamp in its interior, positioning a template above the second surface, the template has a deep drawing opening, moving the stamp along a surface that is aligned normal to at least one of the first or second surfaces, such that material of the respective first and second surfaces is forced into the deep drawing opening, wherein the stamp blocks a channel inside the mandrel until pressurized air acting against a surface of the stamp is large enough to cause the stamp to move, wherein in order to obtain a form-fit connection between the first and second surfaces, a deep drawn portion of the first surface engages behind portions of the second surface that surround a deep drawn portion of the second surface, wherein the template is disposed such that the template does not move in relation to the stamp, and the size of the deep drawing opening remains constant, the stamp is returned to its starting position, the template and mandrel are removed.

6. The method according to claim 5, wherein a joint is obtained by at least partially deforming the material forming the first and second surfaces, which ends up at least partially above and/or outside the first and second surfaces.

7. The method according to claim 5, wherein the stamp moves substantially at a right angle with respect to at least one of the first surface or the second surface.

8. The method according to claim 5, wherein the first part is a closed tube, and the first surface is formed by at least part of the wall of the tube, wherein the tube and the mandrel are positioned such that their respective central axes coincide or are aligned such that their respective central axes have an angular deviation of 10 or less.

Description

(1) FIG. 1: shows a sectional view of a first embodiment of the device for executing the method obtained with the invention;

(2) FIG. 2: shows a sectional view of two parts that are joined together after executing the method obtained with the invention;

(3) FIG. 3.1: shows a first part and three parts permanently connected thereto from above in a first embodiment obtained with the invention, after executing the method obtained with the invention; and

(4) FIG. 3.2: shows a first part and three parts permanently connected thereto from above prior to executing the method obtained with the invention.

(5) A first embodiment of the device 100 for executing the method obtained with the invention is shown in a sectional view in FIG. 1. This device 100 contains a mandrel DO. This mandrel DO is formed by a hollow cylinder with an internal channel KA and a central axis MS. The stamp ST needed for the method is inside the channel KA and seals it in its starting position in a fluid-tight manner. The first part T1 is a closed tube forming a hollow cylinder. The mandrel DO is placed inside the first part T1. The tube can be slid over the mandrel DO. The material of the first part T1 can contain an aluminum alloy and form a seamless tube. The central axis MS is aligned with the central axis of the first part T1. The first part T1 is held in place in a clamp, not shown. The material of the second part T2 can contain an aluminum alloy. The mandrel DO has a lateral opening through which the stamp ST can be moved along the movement axis AS. The movement axis AS is thus perpendicular to the central axis MS. The second part T2 is placed above the first part T1 such that the surface normal of the second surface Z2 is aligned with the movement axis AS. The first part T1 is formed by a tube, and the first surface Z1 is the outer surface of the tube. The first surface Z1 formed by the outer surface of the tube (first part T1) has a simple curvature, and the surface normal of this outer surface substantially coincides with the movement axis AS. The second surface Z2 has a simple curvature. The second surface Z2 on the second part T2 is placed above the first surface Z1 of the first part T1 (seen from the central axis MA). The template MT is placed above the two surfaces Z1, Z2. The template MT is pressed against the two parts T1, T2 during the method obtained with the invention. The template MT contains the deep drawing opening TO. The deep drawing opening TO is formed by a circular blind hole. The medium M flows through the channel KA. The medium M is pressurized air. This can be generated by a compressor, not shown, connected to the channel KA. The stamp ST blocks the channel KA inside the mandrel DO such that the medium M cannot escape, until the pressure from the medium M acting on the stamp ST is strong enough to move the stamp ST along the movement axis AS. Consequently, a force acting along the central axis MS is converted into movement along the movement axis AS, which is substantially perpendicular to the central axis MS, and directed outward. The stamp ST is moved outward through a lateral opening in the mandrel along the movement axis AS. The round, conical working pin AZ on the stamp ST shapes the parts of the respective surfaces Z1, Z2 in the deep drawing opening TO in the template MT. The resulting joint, not shown, is formed starting from the interior and extending outward. The stamp ST is supported by a swivel joint in the mandrel DO. After the pressure of the medium M diminishes, the stamp is returned to its starting position by gravity. The medium M flows out of the channel KA through the opening O when the stamp ST has moved outward along the movement axis AS, because the lateral opening is sealed against the environment by at least the first surface Z1. The channel KA in the mandrel DO is narrowed by the guide F, and a surface on the stamp ST is exposed in a targeted manner to the medium M. Substantially means within a longitudinal deviation of 2 mm and/or angular deviation of 10. These deviations can be attributed to longitudinal displacement or rotation.

(6) Two parts T1, T2 connected by the joint VB obtained with the invention are shown in a sectional view in FIG. 2. The first part Z1 is a closed tube, and can be part of a supply line or drain line for a heat exchanger 200 obtained with the invention. Because the first part Z1 is a tube, the first surface Z1, forming the outer surface of the tube, has a simple curvature. The second part Z1 has the surface Z2 with a simple curvature, and can form a bracket. The second surface Z2 is curved to fit the first surface Z1, such that the first and second parts T1, T2 fit together. This is obtained in that the outer diameter of the tube (first part) and the inner diameter of the second surface Z2 on the second part T2 are substantially the same. The surface normals of the two surfaces Z1, Z2 are substantially aligned with the movement axis AS of the stamp, not shown. The central axis MS is that of the first part T1. The movement axis AS is substantially perpendicular thereto. The joint VB is a circular punctiform joint. The joint VB is advantageously outside the first part T1 and is directed outward. It thus extends outward, away from the central axis MS. The diameter of the tube forming the first part T1 can be greater than 25 mm. The mandrel, not shown, can advantageously be removed without damaging the first part T1, because the joint VB is directed outward, and the mandrel will not catch on it.

(7) A first part T1 and three second parts T2 are shown from above in FIG. 3 prior to and after executing the method obtained with the invention. The first part T1 is a closed tube. The first surface Z1 is the outer surface of the tube, which has a simple curvature. The three second parts Z1 each have the second surface Z2. The second parts T2 are of different sizes. The curvature of the second surfaces Z2 first the simple curvature of the first surface Z1, such that the first part T1 and second part T2 fit together. This is obtained in that the outer diameter of the tube (first part T1) and the inner diameter of the second surface Z2 on the second part T2 are substantially the same. The heat exchanger 200 obtained with the invention contains the first part T1 and second part T2.

(8) A first part T1 and three second parts T2 are shown after executing the method obtained with the invention in FIG. 3.1. The three joints VB are formed from the inside, and the three joints VB are each circular, punctiform joints. A first part T1 and three second parts T2 are shown from above prior to executing the method obtained with the invention in FIG. 3.2.

(9) The specification can be readily understood with reference to the following Numbered Paragraphs:

(10) Numbered Paragraph 1. A joining method comprising the following steps: positioning two surfaces (Z1, Z2) with simple curvatures on two parts (T1, T2) above one another, positioning a mandrel (DO) below the first surface (Z1), which contains a moving stamp (ST) in its interior, positioning a template (MT) above the second surface (Z2), which has a deep drawing opening (T), moving the stamp (ST) along the surface normal of at least one of the two curved surfaces (Z1, Z2), such that material of the respective surfaces (Z1, Z2) is forced into the deep drawing opening (T), wherein, in order to obtain a form-fit connection between the two surfaces (Z1, Z2), the deep drawn and compressed portion of the first surface (Z1) engages behind the remaining part of the second surface (Z2), the stamp (ST) is returned to its starting position, the template (MT) and mandrel (DO) are removed.

(11) Numbered Paragraph 2. The method according to Numbered Paragraph 1, characterized in that the stamp (ST) blocks a channel (KA) inside the mandrel (DO) until the pressure exerted by the medium (M) therein is strong enough to cause the stamp (ST) to move.

(12) Numbered Paragraph 3. The method according to Numbered Paragraph 1 or 2, characterized in that a joint (VB) is obtained by at least partially deforming the material forming the two surfaces (Z1, Z2), which ends up at least partially above and/or outside the two surfaces (Z1, Z2).

(13) Numbered Paragraph 4. The method according to Numbered Paragraph 1, 2 or 3, characterized in that the direction in which the stamp (ST) moves substantially follows at least one of the surface normals of the two surfaces (Z1, Z2).

(14) Numbered Paragraph 5. The method according to any of the preceding Numbered Paragraphs, characterized in that the first part (T1) is a closed tube, and the first surface (Z1) is formed by at least part of the wall of the tube, by wherein the tube and the mandrel (DO) are positioned such that their central axes (MA) substantially coincide.

(15) Numbered Paragraph 6. The method according to any of the preceding Numbered Paragraphs, characterized in that the template (MT) is nearly stationary, and the size of the deep drawing opening (TO) remains constant.

(16) Numbered Paragraph 7. A device (100) for executing the method according to any of the Numbered Paragraphs 1 to 6, characterized in that the channel (KA) has an opening (O) through which the medium (M) can flow out, and is connected to a compressor.

(17) Numbered Paragraph 8. The device (100) according to Numbered Paragraph 7, characterized in that the stamp (ST) is pivotally supported in the channel (KA).

(18) Numbered Paragraph 9. The device (100) according to Numbered Paragraph 7 or 8, characterized in that the mandrel (DO) has a lateral opening (OS) through which the stamp (ST) is moved.

(19) Numbered Paragraph 10. The device (100) according to Numbered Paragraph 7, 8, or 9, characterized in that the lateral opening (OS) in the mandrel (DO) is sealed off from the environment by the first surface (Z1) in a fluid-tight manner.

(20) Numbered Paragraph 11. The device (100) according to Numbered Paragraph 7, 8, 9, or 10, characterized in that the deep drawing opening (TO) in the template (MT) forms a blind hole in both the radial and axial directions thereof.

(21) Numbered Paragraph 12. The device (100) according to Numbered Paragraph 7, 8, 9, 10, or 11, characterized in that the stamp (ST) has a round working pin (AZ), which at least partially enters the deep drawing opening (TO).

(22) Numbered Paragraph 13. A heat exchanger (200) containing at least two parts (T1, T2), which are joined to one another with the method according to any of the Numbered Paragraphs 1 to 6.

(23) Numbered Paragraph 14. The heat exchanger (200) according to Numbered Paragraph 13, characterized in that the first part (T1) is a tube and the second part (T2) is a bracket with which the heat exchanger (200) is attached to another component, wherein the diameter of the tube is greater than 20 mm.

(24) Numbered Paragraph 15. A refrigerant circuit for a motor vehicle that contains at least one heat exchanger (200) according to Numbered Paragraph 13.

LIST OF REFERENCE SYMBOLS

(25) 100 device for executing the method obtained with the invention 200 heat exchanger containing two parts connected to one another by the method obtained with the invention Z1, Z2 surfaces with simple curvatures T1, T2 two parts that are joined to one another with the method obtained with the invention RO tube that has a surface with a simple curvature VB resulting joint DO mandrel for the device MT template for the device KA channel inside the mandrel ST stamp inside the mandrel AZ working pin on the stamp TO deep drawing opening in the template SO lateral opening in the mandrel O opening in the mandrel M medium that flows through the channel BR movement direction for the stamp AS movement axis along which the stamp is moved MS central axis for the mandrel and the first part F guide for the medium