GB1602727A

GB1602727A - Pipe-shaping device

Info

Publication number: GB1602727A
Application number: GB3662877A
Authority: GB
Original assignee: MOTAPRODUCTS AUTOMOTIVE Ltd
Current assignee: MOTAPRODUCTS AUTOMOTIVE Ltd
Priority date: 1978-05-26
Filing date: 1978-05-26
Publication date: 1981-11-18

Description

(54) PIPE-SHAPING DEVICE (71) We, MOTAPRODUCTS AUTO MOTIVE UNITED, a British Company of My prod House, Melchett Road, Birmingham Factory Centre, Kings Norton, West Midlands, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to devices for shaping the end portions of pipes.

The invention is primarily concerned with a device for shaping the end portion of a pipe to be incorporated in a hydraulic braking system of a vehicle, to provide it with an outwardly projecting end flange having an outer end face of convex or concave form for sealing engagement with a complementary face of a connector connecting the pipe to a hydraulic cylinder in the system. The following description will be confined to this application of the invention but it is to be understood that there is no limitation in this regard since the device of the invention may be used for shaping other pipes, usually of relatively small diameters.

A brake pipe shaping device is known which comprises two die halves arranged to be clamped together by screws and formed to provide, when clamped together, a through bore the axis of which lies in the parting plane of the die halves, one end portion of the bore being plain and of a smaller diameter such that an end portion of a pipe introduced into said one end portion with the screws released can be firmly clamped therein and between the die halves by tightening of the screws, and the other end portion of the bore being of a greater diameter and screw-threaded to receive a complementarily screw-threaded component provided with a punch which, on turning of the component in said other end portion, is advanced into deforming engagement with the end of the pipe and thereby shapes it.

Certain problems arise with this known form of device as a result of the screw-thread being formed in the die halves themselves. In manufacture the die halves are cut from metal stock and a groove is milled in each half, the two halves are placed together so that the grooves together form a through bore, one en portion of the bore is drilled to a larger diameter and then tapped to form the screw thread therein, and then holes are formed through the halves at right angles to the bore to receive the clamping screws. This procedun is slow and laborious and the die halves, being of case hardening material, are difficult to machine. The die halves must be maintained at an accurate relative positioning otherwise the thread parts in the respective halves become misaligned and are likely to be strippe on turning of the punch component in the bore end portion.

The object of the present invention is to provide an improved pipe shaping device which, in particular overcomes the above problems of the known brake pipe shaping device.

According to the invention, we provide a pipe shaping device comprising two die parts having means operable releasably to clamp them together and formed to provide, when clamped together, a through bore the axis of which lies in the parting plane of the die parts, one end portion of the bore being formed so that an end portion of a pipe intro- duced into it with the clamping means release can be clamped in said one end portion and between the die halves by operation of the clamping means, and the other end portion of the bore containing an initially separate onepiece insert having a through bore which is screw-threaded to receive a complementarily externally screw-threaded punch component, the arrangement being that, in use, turning of a punch component in the insert advances the punch into deforming engagement with the adjacent end of a clamped pipe thereby to shape it.

By providing the screw thread in an initially separate insert the abovementioned problems do not arise. Thus, less machining of the die parts is needed, and the screwthread can be formed more easily in the onepiece insert than in the die parts themselves.

The said one end portion of the bore to receive a pipe is preferably of a smaller diameter than the said other end portion con taining the insert.

Preferably the insert is located in a cut-away portion of the bore, and this cut-away portion is provided by an aperture which extends right through the die parts and passes transversely through the bore, the insert having portions thereof located in said aperture with its bore concentric with the bore in the die parts. The aperture maybe of rectangular cross-section and wider than the bore, the insert being comp lementarily shaped, whereby the insert can be removed and inserted without separating the die parts.

Preferably the insert is mounted for slight floating movement relative to the die parts, whereby in use, on engagement of a punch in the insert with a pipe end to be shaped, the insert can move to permit self centering of the punch with respect to the pipe.

Further features of the invention will be apparent from the following description, given by way of example with reference to the accompanying drawings, of one form of a vehicle hydraulic brake pipe shaping device embodying the invention.

In the drawings: Figure 1 is a side view of the device, Figure 2 is a section taken on the line II-II of Figure 1, Figure 3 is a side view of one of the identical die halves of the device, Figure 4 is an end view of the die half shown in Figure 3, and Figure 5 is a cross section through the die half shown in Figures 3 and 4.

The brake pipe shaping device illustrated in the drawings comprises two identical sintered metal die halves 10 and 11 formed with aligned holes 12 to receive screws (not shown) which can be tightened to clamp the two halves together and which also serve to mount the die halves on a handle (also not shown).

The die halves are formed to provide, when clamped together, a through bore 13 the axis of which lies in the parting plane of the two halves.

This through bore comprises an end portion 14 of smaller diameter and of plain cylindrical form with a slightly enlarged diameter portion 15 intermediate its ends. With the clamping screws released, an end portion of a brake pipe can be introduced into this bore portion 14 whereupon the screws are tightened to clamp the pipe end portion firmly between the die halves. The shoulders provided at the ends of the enlarged diameter portion 15 grip the pipe end portion and the section of the latter between the shoulder bulges outwardly slightly, this enhancing the clamping effect on the pipe end portions.

The other end portion 16 of the through bore in the die halves is of larger diameter and shaped as shown. The die halves are formed with a rectangular section aperture 17 which extends right through them and passes transversely through the bore end portion 16, the aperture being wider than the latter as shown in Figure 2.

The aperture 17 accommodates with a small clearance a complementarily shaped, initially separate one-piece metal insert 18 which is formed with a screw-threaded through bore 19 concentric with the bore in the die halves.

Engaged in the screw-threaded bore in the insert 18 is a punch component 20 having a complementarily screw threaded portion 21 intermediate its ends. This punch component has at its outer end a hexagonal head 22 for engagement by a spanner and a reference flange 23, and at its inner end an axial blind bore 24 and a countersunk end face. This bore 24 receives with a friction fit a metal punch element 25 which has a rounded end and may be a pin from a needle roller bearing which is strong and hard.

In use, the user holds the device in one hand by means of the handle and manipulates the spanner in the other hand. The punch component 20 is turned relative to the insert 18 and the die halves 10, 11 to bring the reference flange 23 into a position in which the outer face is flush with the adjacent end face of the die halves as shown in Figure 1. With the clamping screws released, the end portion of a pipe P is pushed into the smaller diameter bore end portion 14 until its end abuts the punch component 20 and the punch element 25 extends into the pipe, this correctly positioning the pipe axially. The screws are tightened to clamp the pipe end portion and the punch component 20 is then turned so that the countersunk end face of the punch component acts on the end of the pipe to flare it outwardly and provide the resulting outwardly extending flange with a convex outer end face.

The insert 18 is mounted for slight lateral floating movement in the die halves so that the punch component can move laterally as it starts to deform the pipe and thereby centralise itself with respect to the pipe.

If the flange at the end of the pipe is required to have a concave outer end face, the punch component 20 and the punch element 25 are removed and replaced by another punch component having a rounded nose which, on turning of the component, further deforms the flange and thereby provides it with a concave outer end face.

Instead of using two punches, a single double-ended one-piece punch may be provided for performing the first and, if required, the second shaping operations.

In order to ensure that the two die halves are correctly located with respect to one another, dowels may be provided extending through aligned holes therein, but preferably each die half is formed with a tapered rectangular (or other appropriately shaped) projection 26 (Figures 3, 4 and 5) arranged to be received in a complementary recess 27 in the other die half.

WHAT WE CLAIM IS: 1. A pipe shaping device comprising two die

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. Preferably the insert is located in a cut-away portion of the bore, and this cut-away portion is provided by an aperture which extends right through the die parts and passes transversely through the bore, the insert having portions thereof located in said aperture with its bore concentric with the bore in the die parts. The aperture maybe of rectangular cross-section and wider than the bore, the insert being comp lementarily shaped, whereby the insert can be removed and inserted without separating the die parts. Preferably the insert is mounted for slight floating movement relative to the die parts, whereby in use, on engagement of a punch in the insert with a pipe end to be shaped, the insert can move to permit self centering of the punch with respect to the pipe. Further features of the invention will be apparent from the following description, given by way of example with reference to the accompanying drawings, of one form of a vehicle hydraulic brake pipe shaping device embodying the invention. In the drawings: Figure 1 is a side view of the device, Figure 2 is a section taken on the line II-II of Figure 1, Figure 3 is a side view of one of the identical die halves of the device, Figure 4 is an end view of the die half shown in Figure 3, and Figure 5 is a cross section through the die half shown in Figures 3 and 4. The brake pipe shaping device illustrated in the drawings comprises two identical sintered metal die halves 10 and 11 formed with aligned holes 12 to receive screws (not shown) which can be tightened to clamp the two halves together and which also serve to mount the die halves on a handle (also not shown). The die halves are formed to provide, when clamped together, a through bore 13 the axis of which lies in the parting plane of the two halves. This through bore comprises an end portion 14 of smaller diameter and of plain cylindrical form with a slightly enlarged diameter portion 15 intermediate its ends. With the clamping screws released, an end portion of a brake pipe can be introduced into this bore portion 14 whereupon the screws are tightened to clamp the pipe end portion firmly between the die halves. The shoulders provided at the ends of the enlarged diameter portion 15 grip the pipe end portion and the section of the latter between the shoulder bulges outwardly slightly, this enhancing the clamping effect on the pipe end portions. The other end portion 16 of the through bore in the die halves is of larger diameter and shaped as shown. The die halves are formed with a rectangular section aperture 17 which extends right through them and passes transversely through the bore end portion 16, the aperture being wider than the latter as shown in Figure 2. The aperture 17 accommodates with a small clearance a complementarily shaped, initially separate one-piece metal insert 18 which is formed with a screw-threaded through bore 19 concentric with the bore in the die halves. Engaged in the screw-threaded bore in the insert 18 is a punch component 20 having a complementarily screw threaded portion 21 intermediate its ends. This punch component has at its outer end a hexagonal head 22 for engagement by a spanner and a reference flange 23, and at its inner end an axial blind bore 24 and a countersunk end face. This bore 24 receives with a friction fit a metal punch element 25 which has a rounded end and may be a pin from a needle roller bearing which is strong and hard. In use, the user holds the device in one hand by means of the handle and manipulates the spanner in the other hand. The punch component 20 is turned relative to the insert 18 and the die halves 10, 11 to bring the reference flange 23 into a position in which the outer face is flush with the adjacent end face of the die halves as shown in Figure 1. With the clamping screws released, the end portion of a pipe P is pushed into the smaller diameter bore end portion 14 until its end abuts the punch component 20 and the punch element 25 extends into the pipe, this correctly positioning the pipe axially. The screws are tightened to clamp the pipe end portion and the punch component 20 is then turned so that the countersunk end face of the punch component acts on the end of the pipe to flare it outwardly and provide the resulting outwardly extending flange with a convex outer end face. The insert 18 is mounted for slight lateral floating movement in the die halves so that the punch component can move laterally as it starts to deform the pipe and thereby centralise itself with respect to the pipe. If the flange at the end of the pipe is required to have a concave outer end face, the punch component 20 and the punch element 25 are removed and replaced by another punch component having a rounded nose which, on turning of the component, further deforms the flange and thereby provides it with a concave outer end face. Instead of using two punches, a single double-ended one-piece punch may be provided for performing the first and, if required, the second shaping operations. In order to ensure that the two die halves are correctly located with respect to one another, dowels may be provided extending through aligned holes therein, but preferably each die half is formed with a tapered rectangular (or other appropriately shaped) projection 26 (Figures 3, 4 and 5) arranged to be received in a complementary recess 27 in the other die half. WHAT WE CLAIM IS:

1. A pipe shaping device comprising two die

parts having means operable releasably to clamp them together and formed to provide, when clamped together, a through bore the axis of which lies in the parting plane of the die parts, one end portion of the bore being formed so that an end portion of a pipe introduced into it with the clamping means released can be clamped in the bore portion and between the die halves by operation of the clamping means, and the other end portion of the bore containing an initially separate one-piece insert having a through bore which is screw-threaded to receive a complementarily externally screwthreaded punch component, the arrangement being that, in use, turning of a punch component in the insert advances the punch into deforming engagement with the adjacent end of a clamped pipe thereby to shape it.

2. A pipe shaping device as claimed in claim 1 wherein the said one end portion of the bore to receive a pipe is of a smaller diameter than the said other end portion containing the insert.

3. A pipe shaping device as claimed in claim 1 or 2 wherein the insert is located in a cutaway portion of the bore.

4. A pipe shaping device as claimed in claim 3 wherein the cut-away portion of the bore is provided by an aperture which extends right through the die parts and passes transversely through the bore, the insert having portions thereof located in said aperture with its screwthreaded bore concentric with the bore in the die parts.

5. A pipe shaping device as claimed in claim 4 wherein the aperture is of rectangular crosssection and wider than the bore and the insert is complementarily shaped.

6. A pipe shaping device as claimed in any one of the preceding claims wherein the insert is mounted for slight floating movement relative to the die parts, whereby in use, on engagement of a punch in the insert with a pipe end to be shaped, the insert can move to permit selfcentering of the punch with respect to the pipe.

7. A pipe shaping device as claimed in any one of the preceding claims wherein the said one end portion of the bore to receive a pipe has intermediate its ends an enlarged diameter section whereby in use, on clamping of a pipe end portion in said end portion, the shoulders at the ends of said section grip the pipe end portion and the section of the latter between the shoulders bulges outwardly slightly.

8. A pipe shaping device as claimed in any one of the preceding claims wherein the clamping means comprises screws received in aligned holes in the die parts.

9. A pipe shaping device as claimed in any one of the preceding claims wherein one of the die parts is provided with a projection arranged to be received in a complementary recess in the other die part thereby correctly to locate the die parts with respect to one another.

10. A pipe shaping device as claimed in any one of the preceding claims which is provided with a said punch component for shaping the end of a pipe to be incorporated in a vehicle hydraulic braking system, wherein said punch component has at one end thereof a formation adapted to shape a pipe end to provide it with an outwardly projecting flange having an outer end face of convex form.

11. A pipe shaping device as claimed in claim 10 which is provided with a further said punch component having at one end thereof a formation adapted to shape the flange of a pipe end which has been formed with a convex end face, thereby to provide it with a concave end face.

12. A pipe shaping device as claimed in claim 10 wherein the said punch component has at the other end thereof a formation adapted to shape the flange of a pipe end which has been formed with a convex end face by the formation at said one end of the component, thereby to provide it with a concave end face.

13. A pipe shaping device substantially as herein described with reference to and as illustrated in the accompanying drawings.