WO1997011799A1

WO1997011799A1 - A pressing and a method of and apparatus for making a pressing

Info

Publication number: WO1997011799A1
Application number: PCT/GB1996/002393
Authority: WO
Inventors: Douglas Charles Burton
Original assignee: Itw Limited
Priority date: 1995-09-27
Filing date: 1996-09-27
Publication date: 1997-04-03
Also published as: GB2325186B; GB9817043D0; GB2325186A

Abstract

A plumbing fitting comprising a first part being a pressing of sheet metal and a second part being a pressing of sheet metal, the first and second parts being connected together so that the first part provides a first limb and the second part provides a second limb of the fitting. A method of making a pressing including the step of taking a component having a first end part of tubular configuration of a first diameter and acting thereon to form at least the end part to a second, smaller diameter.

Description

Title: A Pressing and a Method of and Apparatus for Making a Pressing

Description of the Invention

This invention relates to a pressing and to a method of and apparatus for making a pressing. The pressing may be a plumbing fitting and more particularly but not exclusively to a plumbing fitting such as an elbow.

Plumbing fittings are conventionally made by manipulating metal tubing. Such manufacture is expensive both in terms of the manufacturing operations required, and in the use of material.

According to one aspect of the present invention we provide a method of making a pressing including the step of taking a component having a first end part of tubular configuration of a first diameter and acting thereon to form at least the end part to a second, smaller, diameter.

The component may have a second end part at an opposite end thereof to said first end part which may be closed by a transversely extending wall.

Said step may comprise acting on the exterior of said end part with a female tool having a leading part of the diameter which is not smaller than the exterior of said end part and a trailing part of said smaller diameter and acting on the interior of said end part with a mandrel of a size which is adapted to engage with the interior of the end part when the exterior is engaged with the trailing part.

The component may be cup-shaped, the second end part being acted upon by a second female tool having an open mouth and of complementary cup- shape to said second end part and the female dies being relatively movable towards each other to bring the leading part of the first female tool into proximity with the open mouth of the second female tool, and the mandrel moving with the first female tool. The component may be formed by said step so as to have a portion of generally part spherical configuration with the first and second female tools meeting at or adjacent a diameter of the part spherical portion.

According to a second aspect of the present invention we provide a plumbing fitting comprising a first part being a pressing of sheet metal and a second part being a pressing of sheet metal, the first and second parts being connected together so that the first part provides a first limb and the second part provides a second limb of the fitting.

The first part may comprise a body portion having an internal hollow, and a first opening to the hollow at one end of the first limb, formed by a pressing operation, and a second opening to the hollow through a side wall of the limb, formed by a piercing operation. Thus fluid may flow through the first part between the first and second openings.

The first opening may be adapted to be connected to a conduit. For example, the plumbing fitting at the first opening, may be adapted to be screwed, welded, or otherwise connected to a conduit such as a pipe, or a radiator, or another plumbing fitting, having a passage therethrough for fluid.

The second part may comprise a body portion having an internal hollow, there being first and second openings from the hollow at either end of the second limb, the first formed by a pressing operation, and the second formed by a piercing operation, one of the openings from the hollow of the second part communicating with the internal hollow of the first part via the second opening to the internal hollow of the first part.

Thus fluid may flow between the first and second openings of the second part and by virtue of the communication with the hollow of the first part, fluid may flow through the fitting between the first opening of the first part and the other of the openings of the second part. The other of the openings from the hollow of the second part may be adapted to be connected to a further conduit. For example, a region of the body portion adjacent the other of the openings which is adapted to be connected to the further conduit, may comprise a screw thread such as a female screw thread provided internally of the opening.

The first and second limbs of the fitting may be arranged to extend mutually perpendicularly to one another. Thus the fitting may comprise an elbow.

The first and second parts of the fitting may be welded together so as to provide a fluid-tight joint between the one of the openings from the hollow of the second part and the second opening of the first part.

According to a third aspect of the invention we provide a method of manufacturing a plumbing fitting comprising the steps of making a first part by pressing a first blank of sheet metal, making a second part by pressing a second blank of sheet metal, connecting the first and second parts together so that the first part provides a first limb and the second part provides a second limb of the fitting.

The first part may be formed by pressing with a body portion having an internal hollow, and a first opening at one end of the first limb, to the hollow, and a second opening to the hollow may be formed through a side wall of the limb, by a piercing operation.

The method may include providing the first opening of the first part with a chamfer to facilitate its connection to a conduit such as a pipe, radiator or the like, or other fitting e.g. by welding.

The method may include forming the second part, during the pressing operation, with a body portion having an internal hollow and a first opening from the hollow at one end of the second limb, and a second opening may be formed by a piercing operation at an opposite end of the second limb.

The first and second parts of the fitting may be connected together e.g. by welding, prior to the second opening being provided in the first part.

Thus subsequent to the second opening being formed in the side wall of the first part, one of the openings from the hollow of the second part may communicate with the internal hollow of the first part via the second opening to the internal hollow of the first part. A region of the body portion adjacent the, or one of the openings which is adapted to be connected to a conduit, may be provided with a screw thread, such as a female screw thread internally of the opening.

The first blank of sheet metal may be pressed to form the first part of the fitting by a pressing operation which includes the steps of drawing a circular blank to a generally cup shaped element, and reducing the diameter of the open end of the cup to provide the first opening.

The first part may be made by a method according to said one aspect of the present invention.

The second blank sheet of metal may be pressed to form the second part of the fitting by a pressing operation which includes the steps of drawing a circular blank to a generally cup shaped element, the open end of the element providing one of the first and second openings, and the closed end of the element may subsequently be pierced to provide the other of the first and second openings.

The open end of the cup-shaped element which is formed during pressing may be provided with an out-turned lip to facilitate its connection to a further conduit.

The invention will now be described with reference to the accompanying drawings in which:

Figure 1 shows various steps in the method of the invention, for forming the first part of the fitting;

Figure 2 shows various steps in the method of the invention for forming the second part of the fitting;

Figure 3a shows the first and second parts after being assembled and welded together;

Figure 3b_ shows to an enlarged scale portions of the first and second parts after being assembled but prior to welding;

Figure 3c shows the portion of Figure 3b_ but after welding.

Figure 4 is a vertical sectional view showing the final fitting. Figure 5 is a central longitudinal sectional view of a set of dies for use in the method described hereinbefore.

Referring first to Figure la. a first part of a plumbing fitting is formed from a circular blank 10 into a generally cup-shaped element 11 indicated in Figure lb. This can be achieved by drawing the blank 10 in well known manner using dies B.

The cup-shaped element is further drawn as indicated in Figure lc and a rim 12 of the cup-shaped element 11 is then formed into an outwardly extending flange as indicated at 13 in Figure Id. again in well known manner using dies C and D.

The flange 13 is then removed as indicated in Figure le. by means of a pinch-trim punch and formed with an inclined annular rim 14, which depends internally of the cup shaped element 11 from a periphery 15 of the cup-shaped element lla, by means of an angled form on the face of the pinch-trim punch E.

The periphery 15 is then chamfered as indicated in Figure If to provide an external inclined annular chamfer surface indicated at 16 by means of a set tool F.

The cup-shaped element 11, is then further pressed in well known manner in dies G to form in the closed end 17 of the cup shaped element, a boss formation 18 as shown in Figure lg.

Finally the open end of the cup-shaped element 11 is reduced in diameter to form an opening 20 indicated in Figure lh. Furthermore in this pressing step, the side wall 19 of the cup-shaped element lla is deformed outwardly so as to provide a curved or bulbous side wall surface indicated at 21.

The above referred to step described reference to Figure lh is performed in the apparatus illustrated in Figure 5. A first female tool or die is indicated at 50 and has a part-spherical leading part 51 of a diameter which corresponds to the diameter of the exterior 52 of a tubular end part 53 of the component shown in Figure lg and a trailing part 54 which is of a desired smaller diameter which in the present example comprises a cylinder which corresponds to the diameter of the boss formation 18. A mandrel 55 is disposed within the female die part 50 and has a generally cylindrical extemal surface part 56 of a diameter so as to be spaced from the part 54 of the female die by a distance equivalent to the desired wall thickness of the component shown in Figure lh. The mandrel 55 has a leading end part 57 which is of part-spherical configuration to aid flow of the tubular end portion 53.

The first female die 50 is adapted to co-operate with a second female die 58 having a cavity 59 of part-spherical configuration and with a trailing end part 60 of a configuration corresponding to the boss 18 shown in Figure lh. An ejector 61 is slidably mounted in the second die 58 in conventional manner.

In use, the component shown in Figure lg is positioned in the second female die 58 and the first female die 50 is moved downwardly into contact therewith in conventional manner by positioning the die parts as a die set in a press. The leading end part 53 of the component shown in Figure lg is acted upon by the part-spherical surface 51 and is caused to bend inwardly so as to be guided by the mandrel 55 into the gap between the mandrel and the part 54 of the die cavity so as to reduce the diameter of the tubular part 52 and provide a configuration as shown in Figure lh. The trailing end part 60 of the second female die 58 co-operates with the closed end 17 having the boss formation 18 and may perform a further forming operation.

Referring now to Figure 2, a second part of a plumbing fitting is formed by generally known techniques from a second generally circular sheet metal blank indicated at 25 in Figure 2a. The blank 25 is drawn by a pressing operation to the configuration shown at 26 in Figure 2b. Further pressing (drawing) forms a cup-shaped element 26a indicated in Figure 2c.

The closed end 27 of the cup-shaped element 26a is then pressed to a squarer configuration as indicated at 27a in Figure 2d. The free end 28 of the cup-shaped element 26a is then formed to provide an outwardly extending flange indicated at 29 in Figure 2e. Next, the closed end 27a of the cup-shaped element 26a is pierced as indicated in Figure 2f to provide an opening 30. Some machining is then carried out to form chamfers, one of which is indicated at 31 at the end at which the flange 29 is provided. A further chamfer 32 is provided at the end remote from the flanges 29 around the opening 30. The resultant configuration is shown generally in Figure 2g and, to an enlarged scale in Figure 3b, where it will be seen that the bottom edge, in cross-section, has a radially outer part of curved shape which merges with a straight shape.

In Figure 2h a clipping operation is performed and it can be seen that the extent of the flange 29 has been reduced by removing some of the flange to leave the final second part component.

Referring now to Figure 3a_-c, the first part made by the method described with reference to Figures la to lh, and the second part which was made by a method described with reference to Figures 2a to 2h, are assembled and welded together.

During welding the side wall 32a. of the second part, in the region of the chamfer 32 is distorted and the chamfer 32 is pushed radially outwards, as shown in Figures 3b_ and 3c, thereby providing a high integrity join with the bulbous exterior side wall 19 of the first part. Comparison of Figures 3b and 3£ shows how the wall of the second part is shaped during the welding operation.

Next, the part of the exterior bulbous wall 19, which is indicated at 21 in Figure 3a, is removed by piercing using a drill inserted through the open end of the second part to leave the configuration shown in Figure 4.

Thus the resultant fitting indicated at 45 is an elbow and fluid can flow through the fitting from the opening 20 provided by the first part, to the opening 29a provided by the second part, through the interior hollow H of the fitting.

In Figure 4 it can be seen that the limb of the elbow fitting provided by the second part is internally screw threaded as indicated at 46, to facilitate connection of the fitting 45 to a conduit such as a pipe, another plumbing fitting, or an article such as a radiator. The limb provided by the first part of the fitting at opening 20, is adapted to be welded or otherwise connected to a further conduit such as a pipe, another plumbing fitting, or an article such as a radiator e.g. by welding.

Various modifications may be made without departing from the scope of the invention. Particularly, the first and/or second part of the fitting may be made from sheet metal by pressing operations which differ from those described. Further, when the first and second parts are connected together, although in the example shown, the limbs of the fitting extend generally perpendicularly to one another, in another arrangement, another angle may be suspended between the limbs.

If desired, the second part could be connected to the first part at the closed end 18 of the first part so as to provide a straight through connector.

If desired, the opening 20 provided by the first part may be provided with a screw thread or may otherwise be adapted to be connected to a further conduit. Such a screw thread, and/or the screw thread 46 provided on the second limb provided by the second part may be provided exteriorly of the fitting if so desired.

Preferably the fitting is made from steel blanks 10 and 25, although it may be made from other materials if desired.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A method of making a pressing including the step of taking a component having a first end part of tubular configuration of a first diameter and acting thereon to form at least the end part to a second, smaller, diameter.

2. A method according to claim 1 wherein the component has a second end part at an opposite end thereof to said first end part which is closed by a transversely extending wall.

3. A method according to claim 1 or claim 2 wherein said step comprises acting on the exterior of said end part with a female tool having a leading part of the diameter which is not smaller than the exterior of said end part and a trailing part of said smaller diameter and acting on the interior of said end part with a mandrel of a size which is adapted to engage with the interior of the end part when the exterior is engaged with the trailing part.

4. A method according to any one of the preceding claims wherein the component is cup-shaped, the second end part being acted upon by a second female tool having an open mouth and of complementary cup-shape to said second end part and the female dies being relatively movable towards each other to bring the leading part of the first female tool into proximity with the open mouth of the second female tool, and the mandrel moving with the first female tool.

5. A method according to any one of the preceding claims wherein the component is formed by said step so as to have a portion of generally part spherical configuration with the first and second female tools meeting at or adjacent a diameter of the part spherical portion.

6. A method substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

7. A plumbing fitting comprising a first part being a pressing of sheet metal and a second part being a pressing of sheet metal, the first and second parts being connected together so that the first part provides a first limb and the second part provides a second limb of the fitting.

8. A fitting according to claim 7 wherein the first part comprises a body portion having an internal hollow, and a first opening to the hollow at one end of the first limb, formed by a pressing operation, and a second opening to the hollow through a side wall of the limb, formed by a piercing operation.

9. A fitting according to claim 8 wherein the first opening is adapted to be connected to a conduit.

10. A fitting according to claim 8 or claim 9 wherein the second part comprises a body portion having an internal hollow, there being first and second openings from the hollow at either end of the second limb, the first formed by a pressing operation, and the second formed by a piercing operation, one of the openings from the hollow of the second part communicating with the internal hollow of the first part via the second opening to the internal hollow of the first part.

11. A fitting according to claim 10 wherein the other of the openings from the hollow of the second part is adapted to be connected to a further conduit.

12. A fitting according to claim 10 or claim 11 wherein the first and second limbs extend mutually perpendicularly to one another.

13. A fitting according to claim 12 wherein the fitting comprises an elbow.

14. A fitting according to any one of claims 8 to 13 wherein a region of the body portion adjacent the, or one of the openings which is adapted to be connected to a conduit, comprises a screw thread.

15. A fitting according to claim 14 wherein the screw thread comprises a female screw thread provided internally of the opening.

16. A fitting according to any one of the preceding claims wherein the first and second parts of the fitting are welded together.

17. A fitting substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

18. A method of manufacturing a plumbing fitting comprising the steps of making a first part by pressing a first blank of sheet metal, making a second part by pressing a second blank of sheet metal, connecting the first and second parts together so that the first part provides a first limb and the second part provides a second limb of the fitting.

19. A method according to claim 18 wherein the first part is formed by pressing with a body portion having an internal hollow, and a first opening at one end of the first limb, to the hollow, and a second opening to the hollow is formed through a side wall of the limb, by a piercing operation.

20. A method according to claim 19 wherein the method includes providing the first opening with a chamfer to facilitate its connection to a conduit.

21. A method according to claim 19 or claim 20 wherein the method includes forming the second part, during the pressing operation, with a body portion having an intemal hollow and a first opening from the hollow at one end of the second limb, and a second opening is formed by a piercing operation at an opposite end of the second limb.

22. A method according to any one of claims 18 to 21 wherein the first and second parts are connected together prior to the second opening being provided in the first part.

23. A method according to claim 22 where appendant to claim 19 wherein subsequent to the second opening being formed in the side wall of the first part, one of the openings from the hollow of the second part communicates with the internal hollow of the first part via the second opening to the internal hollow of the first part.

24. A method according to any one of claims 19 to 23 where appendant to claim 13 wherein a region of the body portion adjacent the, or one of the openings which is adapted to be connected to a conduit, is provided with a screw thread.

25. A method according to claim 24 wherein the method comprises forming a female screw thread internally of the opening.

26. A method according to any one of claims 18 to 25 which includes the step of connecting the first and second parts together by welding.

27. A method according to any one of claims 19 to 26 where appendant to claim 13 wherein the first blank of sheet metal is pressed to form the first part by a pressing operation including the steps of drawing a circular blank to a generally cup shaped element, and reducing the diameter of the open end of the cup to provide the first opening.

28. A method according to any one of claims 18 to 22 wherein said first part is made according to any one of claims 1 to 6.

29. A method according to any one of claims 22 to 28 where appendant to claim 22 wherein the second blank sheet of metal is pressed to form the second part by a pressing operation including the steps of drawing a circular blank to a generally cup shaped element, the open end of the element providing one of the first and second openings, and the closed end of the element is subsequently pierced to provide the other of the first and second openings.

30. A method according to claim 29 wherein the open end of the cup shaped element formed during pressing is formed with an out-turned lip.

31. A method of manufacturing a fitting substantially as hereinbefore described with reference to the drawings.

32. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.