GB2297506A

GB2297506A - Pipe crimping apparatus

Info

Publication number: GB2297506A
Application number: GB9502000A
Authority: GB
Inventors: Santiago Azurmendi Berasategui
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-02-02
Filing date: 1995-02-02
Publication date: 1996-08-07
Anticipated expiration: 2015-02-02
Also published as: GB2297506B; GB9502000D0

Abstract

The apparatus incorporates a folding mechanism 1, provided with a variable inclination free turning crimping roller 2 applicable to the end of a pipe. The roller 2 is progressively tiltable upon the pipe by the actuation of a rod 6 linked to a hydraulic actuation double effect cylinder 8. The apparatus is also provided with a hydraulic centering mechanism 5 that determines the adaptability of the crimping roller 2 to any pipe outside diameter.

Description

PIPE CRIMPING HEADSTOCK. SPECIALLY FOR SHOCK ABSORBER PIPES DESCRIPTION OBJECT OF THE INVENTION The object of this invention is a device designed to curl the perimeter edge of circular pipes, and specially those of the external pipes of shock absorbers so that the upper and lower pipe surface may be shaped through inward folding of the pipe ends.

The purpose is to optimize the crimping operation by acting with a constant force upon the edge of the external pipe using a roller that progressively folds the pipe end, at the same time that the part upon which the roller is mounted turns in respect of a pin through the action of a hydraulically displaceable piston that determines roller inclination during the crimping operation.

It does also incorporate a pipe centering system which purpose is to guarantee the adaptability of the device to pipes of differing diameter.

BACKGROUND OF THE INVENTION The need to establish a shock absorber air tight closure, thus constituting a cylinder closed at both ends to be used to house inside it a displaceable piston determines that the pipe ends be crimped shaping their upper and lower surfaces. This prevents the need to employ an independent stub end or cover as was normally found welded instead of crimped, given that this is a solution leading to an early wear of the sealing joints as a consequence of the oil warming up.

The shock absorber pipe folding operation is currently carried out through the application of a headstock incorporating a fixed crimping roller in the horizontal position, being joined this headstock to a rotating axis linked to a motor, being each headstock applicable to pipes of the same diameter.

The application of the rotating roller in the perpendicular position in respect to the ends of the pipe requires a considerable pressure and causes stresses in the pipe structure that may cause its failure.

The traditional system consists of carrying out the shock absorber pipe crimping operation once all the elements making it up are assembled, causing in some cases breakages or damage to the shock absorber seal joint protecting the linkage.

DESCRIPTION OF THE INVENTION This invention consists of a headstock to crimp the ends of the pipes, specially shock absorber pipes, shaping their upper and lower surfaces through the application of a progressive displacement roller that makes it possible to fold the pipe ends with less force and greater accuracy than that required in the systems traditionally employed, being it possible to adapt this device to fold pipes of various diameters.

The headstock contains fundamentally a folding mechanism and a pipe centering mechanism.

The folding mechanism is made up of a crimping roller arranged centrally with respect to a roller carrier supporting it and to which it is interlocked, being said roller carrier capable of turning in relation to a fixed support with the aid of two pins arranged at its ends, with the rocking movement of the roller carrier being determined by the action of a rod associated to a piston introduced into a hydraulic action double effect cylinder.

The crimping roller is initially located in a tilted position with its upper surface higher than 45 , being this roller sector the top against which the pipe stops when introduced at pressure inside the headstock, thus obtaining an initial pipe fold with the same inclination as the roller. In this situation the piston is at its lower position.

During the movement of the piston towards its upper position there is a turning displacement of the roller carrier on the vertical plane in respect to a fixed supporting pin, and consequently the progressive inclination of the roller that pressures the pipe causing a fold progressively greater at the pipe ends until a horizontal surface is shaped, situation that corresponds to the upper piston position.

The crimping roller turns freely inside its housing, which allows it to rotate during the crimping operation, in which the headstock undergoes a turning movement and the pipe remains still.

The pipe is held using stops consisting of three milling rollers that allow using the device during the crimping operation, self adapting to the diameter of the pipe to be folded and pressing upon the pipe edge while it is being folded to prevent it from increasing its diameter.

The central milling roller is located at one of the ends of the centering mechanism, said mechanism consisting of a structure linearly displaceable through the hydraulic actuation of a cylinder, which contains a piston in respect of which it slides externally, being the rod of the piston linked to the headstock frame. This assembly features laterally triangular fins that are permanently in contact with matching wheels on respective turning levers, which rotate around an intermediate fixed axis and have at their ends the already mentioned contact milling rollers.

The inward displacement of the centering mechanism to adapt to the pipe diameter determines the slide of the lever wheels and consequently the rotation of the levers and of the milling rollers acting upon the pipe side surface.

The folding mechanism is also linearly displaceable through hydraulic actuation so as to adapt the crimping roller to the pipe end to be folded, having the support a slot form that slides in relation to an internally arranged piston, being the piston end rod linked to the frame.

The centering mechanism and folding mechanism, feature upper sections through which said mechanisms are linearly displaceable upon internal lateral guides, being the oil distribution hydraulic system internally located in relation to said sectors.

The folding and centering mechanism have associated to them a displacement interval within which they may move and which shall determine the diameter range of the pipes that they may crimp. This interval is defined by the thickness of washers corresponding to each one of the mechanisms and upon which act the nuts linking the fixed rods to the frame mechanism.

The maximum displacement of each one of the mechanisms and consequently the range of diameters of the pipes that may be folded shall be defined depending upon the washer size DESCRIPTION OF THE DRAWINGS In order to complete the description being made and with the purpose of achieving a better understanding of the characteristics of the invention, a set of drawings is attached to this patent specification, forming an integral part thereof and in which the following features have been represented with an illustrative but not limitative character: Figure 1.- Shows a front view of the pipe crimping headstock with part of its parts cut away.

Figure 2.- Shows a plan view of the headstock with its lower section cut away and its elements arranged in the position of holding a pipe of a given diameter, and with its upper half whole with the elements integrating the headstock in coupling position with a low diameter pipe. This figure does not show the so called upper sectors of the centering and folding mechanisms, nor the internal guide.

PREFERENTIAL EMBODIMENT OF THE INVENTION On observing the figures it may be said that this invention regarding a pipe crimping headstock, specially for shock absorbing pipes, incorporates a folding mechanism (1) fitted with a variable inclination crimping roller (2) applicable upon the pipe (10) and a pipe centering mechanism (5) that allows the use of the device for pipes of different diameters.

The folding mechanism (1) is fundamentally made up of a free turning crimping roller (2) applicable upon the pipe perimeter edge (10), rotating said roller in respect of a rod (17) located in the central housing of a roller carrier (3), that turns in relation to the pins (23) linked to a support (4) with which the roller carrier (3) maintains its opposite lateral surfaces parallel, being determined the variable roller inclination (2) by the displacement of a rod (6) impinging against the roller carrier (3).

The rod (6) is linked at its opposite end to a piston (7) incorporated inside a double effect hydraulic action cylinder (8), said cylinder (8) rocking in respect of the structure of the folding mechanism by means of the pin (9).

During the upward piston (7) displacement there is a progressive inclination of the crimping roller (2) pressing upon the pipe (10) edge and folding it inward 90" in relation to its vertical position. With the purpose of achieving the crimping operation through roller (2) application, the pipe (10) is previously deformed to 45" at one of its points through impact of the pipe against the upper section of the roller side surface (2) positioned with this inclination.

The fixture of the pipe (10) upon the headstock is established through the centering mechanism (5), adapting upon the side pipe surface a central milling roller (11) and side milling rollers (12, 12'), being said rollers capable of turning at the same time that they hold the pipe during the turn of the motor actuated headstock, thus preventing the pipe remaining fixed from increasing its diameter during the crimping operation.

The centering mechanism (5) shows an assembly linearly displaceable through hydraulic actuation of a mobile cylinder (18) in relation to a piston (19) arranged internally to said cylinder, being the piston (19) fixed to the headstock frame (20) by a rod (21) threaded into a nut (22).

The cylinder (18) evidences triangular fins (13) that remain in contact with matching wheels (14, 14') corresponding to the ends of the levers (15, 15') that present an intermediate turn axis associated to the supports (16, 16') respectively and the milling rollers (12, 12') arranged at their ends. Whenever the cylinder moves linearly (18) to adapt the milling rollers to the side surface of the pipe (10), the wheels (14, 14') slide upon the side fins (13), rotating the levers and consequently the rollers (12, 12'), contacting with the side surface of the pipe at the same time as the other roller (11), leaving the pipe (10) perfectly centered.

The assembly fitted upon the support (4), belonging to the folding mechanism (1) moves by way of hydraulic actuation so that the slot form set into the support (4) on its back face slides in respect to the axis (24), linked to the frame (2) of the headstock by one of its ends, which is threaded inside a nut (25).

The mobility and consequently the adaptability of the folding (1) and centering (5) mechanisms to a given pipe diameter range (10) is conditioned by the thickness of the washers (26) that are pressed against the nuts (21) and (25) in relation to the headstock frame (20).

In order to facilitate the movement of the folding (1) and centering (5) assemblies, they have two upwards prolonged sections (27) and (28) that travel upon internal guides (2) giving a greater degree of displacement precision to each of the assemblies.

It is not considered necessary to extend this description any further in order to enable any expert in this matter to comprehend the scope of the invention and the benefits derived therefrom.

The materials, shape, size and distribution of the elements may be modified at any time as long as they do not alter the essential features of the invention.

The terms described in this specification must always be taken in a wide and not limitative sense.

Claims

CLAINS

1. A pipe crimping apparatus essentially comprising a folding mechanism (1) provided with a variable inclination crimping roller adapted for application against a pipe end and a pipe centering mechanism (5) adaptable to pipes of different diameters.

2. A pipe crimping apparatus as claimed in Claim 1, wherein the folding mechanism consists of a free turning crimping roller (2) applicable upon a pipe perimeter edge (10) in use, said roller being rotable in relation to a pin (17) located in a central housing of a roller carrier (3), said roller carrier (3) being pivotable in relation to pins (23) linked to a support (4) with which the roller carrier (3) maintains its end side surfaces parallel, wherein the variable inclination of the roller (2) is determined by the displacement of a rod (6) that impinges upon the roller carrier (3), said rod (6) being linked at its opposite end to a piston (7) incorporated inside a double effect hydraulic action cylinder (8), said cylinder (8) being pivotable in relation to the folding mechanism by way of a pin (9).

3. A pipe crimping apparatus as claimed in Claim 1 or Claim 2, wherein the roller (2) tilts from a first position corresponding to an extended piston position in the cylinder (8) to a second position corresponding to a retracted piston position (7).

4. A pipe crimping apparatus as claimed in any preceding Claim, wherein the centering mechanism (5) incorporates a linearly displaceable mobile cylinder (18) provided with matching projections (13) in contact at their lower ends with matching wheels (14,14') slidable in relation to said projections, said wheels (14,14') being mounted on fore ends of levers (15,15'), said levers having an intermediate pivot associated with supports (16,16'), and pipe contacting milling rollers (12,12') located at the other ends, and wherein said centering mechanism (5) incorporates another pipe contacting milling roller (11) arranged lower in relation to the cylinder and projecting inward.

5. A pipe crimping apparatus as claimed in any preceding Claim, wherein the cylinder (18) is mobile in relation to a piston (19) arranged inside said cylinder, the piston (19) being fixed to the apparatus frame (20) through a rod (21) threaded to a nut (22).

6. A pipe crimping apparatus as claimed in any preceding Claim, wherein the support (4) moves through hydraulic actuation so that a recess provided in the back surface of the support (4) slides in relation to an axis (24) linked to the apparatus frame (20) through one of its ends, threaded inside a nut (25).

7. A pipe crimping apparatus as claimed in any preceding Claim, between the apparatus frame (20) and the nuts (25) are washers (26) defining the displacement intervals of the folding and centering mechanisms and consequently the range of diameters of pipes capable of being crimped.

8. A pipe crimping apparatus substantially as described herein with reference to the drawings.