WO2001044705A1

WO2001044705A1 - Pipe and device for fixation of pipes

Info

Publication number: WO2001044705A1
Application number: PCT/SE2000/002536
Authority: WO
Inventors: Ola Rolandsson; Thomas ENGSTRÖM
Original assignee: Volvo Articulated Haulers Ab
Priority date: 1999-12-14
Filing date: 2000-12-14
Publication date: 2001-06-21
Also published as: SE9904599L; SE9904599D0; SE515619C2; AU2563501A

Abstract

A device for fixation of a pipe, which device comprises first and second holding members, which in a joined condition exhibit a recess intended to at least partly surround the pipe, and a locking member for fixation of the holding members to each other, whereby clamping of the pipe is achieved.

Description

Pipe and device for fixation of pipes

Technical field

The invention relates to a device for fixation of pipes according to the preamble of claim 1, and a pipe and a device for fixation of pipes according to the preamble of claim 7. In particular, the invention relates to a device for fixation of a pipe to a vibrating foundation, such as, for example, an internal combustion engine, where great demands are placed upon the ability of the device to fixate the pipe, in order to prevent relative movement between the engine and the pipe

Background of the invention

Devices for fixation of pipes in such a way as to avoid rotational and axial movement of the fixated pipe are previously known.

From US 5,839,703 a clip is previously known, comprised of a substantially U-shaped stπp with two vertical lateral walls and a horizontal upper wall which unites said lateral walls. In each of the lateral walls, a resilient hp is arranged. Said lip is shaped from a partial area of said lateral wall, which area is attached to the lateral wall and extends from the attachment obliquely towards the opposite lateral wall and said upper wall. The fixating device fixates the pipe by pressing the pipe past said resilient lips, whereby the pipe is subsequently pressed by the lips against the upper wall, while at the same time the pipe is prevented from rotating by contacting the respective lateral wall. In or- der to ascertain that fixation takes place in a satisfactory manner, the pipe is designed with an area of rectangular cross-section. Fixation in the longitudinal direction of the pipe is achieved by the pipe exhibiting shoulders at the transition from the area of rectangular cross-section to the normal, circular cross-section of the pipe. The length of the area exhibiting a rectangular cross-section is chosen to conform to the length of the clip

Further, from US 4,826,114, another type of clip for holding pipes is known, which takes advantage of the occurrence of a deformed area on the pipe. This pipe clip is de- signed for a pipe exhibiting a mantle surface with a cross-section comprising one or more circle segments extending along the major part of the periphery of the pipe, and one or two areas in which the cross-section is formed by cordae that connect said circle segments. Thus, the pipe exhibits a substantially circularly cylindrical mantle surface with one or two recessed flat surfaces. The pipe is fixated in the longitudinal direction because the extension of the deformed areas in the longitudinal direction of the pipe corresponds to the longitudinal extension of the clip.

Technical problem

When using a clip, such as disclosed in US 5,839,703, particularly in heavily vibrating environments, such as when fixating a pipe in connection to internal combustion engines, a number of problems arise. The clip disclosed in US 5,839,703 consists of a metal strip with resilient lips, intended for holding the pipe against the upper wall. The lips have to be designed sufficiently weak in order to allow the pipe to be forced past them. This means that the pipe is retained by a relatively weak counter-resilience, which may give rise to oscillation of the pipe in the clip against the lips. Further, because the construction is shaped from a metal strip, it is as a whole relatively weak, which entails a risk that the pipe is forced out of position, axially as well as radially, when the pipe is subjected to large forces. Further, the pipe has to be heavily deformed, since it exhibits a rectangular cross-section. This means that high stress arises along the edge connecting the planar surfaces. This entails a risk of crack formation in the pipe, in particular if the pipe is deformed without prior heating, which is practise if the pipe is deformed in-situ prior to mounting. Further, the rectangular cross-section implies a large deviation from a circular cross-section, which means that the flow through the rectangular cross-section is disturbed considerably, resulting in increased flow losses. The pipe will exhibit a considerably reduced cross-sectional area at the rectangular cross section. The fixation device described in US 5,839,703 does not achieve conical centring of the pipe whereby a risk arises that the pipe becomes crookedly fixed. This disadvantage is aggravated by the generally weak construction of the clip, allowing deformation of the clip during centring. The clip disclosed in US 4,826,114 is also afflicted with similar problems with regard to the weak construction of the clip. This means that sufficient resistance to rotation cannot be achieved. In this application, a conical centring of the pipe is also not achieved, whereby a πsk arises that the pipe becomes crookedly fixed

Summary of the invention

The object of the invention is to provide a device for fixation of a pipe in connection to a vibrating foundation, such as, for example, an internal combustion engine, whereby the device provides a fixation of a pipe that provides sufficient resistance, on the one hand against rotation of the pipe, and on the other hand against displacement of the pipe in the longitudinal direction of the pipe. A second object of the invention is to provide a combination of pipe and device for the fixation of said pipe, whereby the device provides a fixation of a pipe, which fixation provides sufficient resistance against rotation of the pipe, and against displacement of the pipe in the longitudinal direction of the pipe, while at the same time reducing the flow resistance in the deformed area. A third object of the invention is to provide a pipe clip that allows conical centring of a pipe exhibiting a conically deformed area

Said object is achieved by means of a device for fixation of a pipe in connection to a vibrating foundation, which is designed in accordance with the characterising part of claim 1, and a pipe and a device for fixation of said pipe, which is designed according to the characterising part of claim 7

According to a first preferred embodiment of the invention, the device for fixation of a pipe is supplied with a first holding member, exhibiting a wedge-shaped groove comprising first and second flat walls, which are intended to contact, duπng clamping of said pipe, two corresponding surfaces of the pipe, and said second holding member compπses at least one surface with a circle segment-shaped cross section intended, duπng clamping of said pipe, to contact a corresponding surface of the pipe. By designing the first holding member with a wedge shaped groove comprising a first and second flat side wall, which are intended, duπng clamping of said pipe, to contact two corresponding surfaces of the pipe, and the second holding member with a groove with a circle segment-shaped mantle surface, intended, during clamping of said pipe, to contact a corresponding surface of the pipe, good fixation of the pipe is obtained due to the conical centring of the pipe that takes place.

Brief description of the drawings

One embodiment of the invention will be described below in greater detail with reference to the attached drawings in which:

Fig. 1 shows a side view of an embodiment of the fixation device exhibiting two through passages for fixation of one pipe each,

Fig. 2 shows a perspective view of components including the deformed pipes, and

Fig. 3 shows a perspective view of the fixation device with the pipes mounted.

Detailed description of preferred embodiments

Fig. 1 shows a preferred embodiment of a device for fixation of a pipe, which device is generally designated as 1. The device comprises a first holding member 2, a second holding member 3, and a locking member 4 for fixation of the holding members against each other, whereby clamping of a pipe can be attained. The locking member is designed in the form of a bolted joint, and comprises a threaded screw 4, arranged to run through a through passage 5 arranged in the first holding member 2, and grip the threads 6 arranged in a hole arranged in the second holding member 3.

The first holding member 2 exhibits an upper limiting surface 7, and a lower limiting surface 8. The device further exhibits two recesses 30, 31. These recesses are formed from first and second grooves 9, 10, situated in the lower limiting surface 8 of the first holding member, and the corresponding groove in the second holding member. The first groove 9 is formed from first and second lateral surfaces 11, 12 and a bottom surface 13, which connects the first lateral surface 11 to the second lateral surface 12. The three surfaces are positioned edge to edge, and thereby form a wedge-shaped groove. The second groove 10 is designed with a mantle surface 14, which exhibits a circle segment- shaped cross section. This mantle surface is intended, during clamping of said pipe, to contact a corresponding surface of the pipe.

The wedge-shaped groove 9 in the first holding member 2 is arranged to cooperate with a first groove 15 situated in the second holding member 3. The first groove 15 of the second holding member is designed with a mantle surface 15 which exhibits a circle segment-shaped cross section. This mantle surface is intended, during clamping of said pipe, to contact a corresponding surface of the pipe.

The second groove 10 in the first holding member, exhibiting a mantle surface with a circle segment-shaped cross section, is arranged to cooperate with a second groove 16, situated in the second holding member.

The first and second grooves 9, 10 are separated by a ridge 17, which is delimited by the second lateral surface 12 of the first groove 9 and the circle segment-shaped mantle area 14 of the second groove 10, and a flat top surface 18. The flat top surface faces a corresponding top surface 19 of a ridge 20, arranged on the flat upper limiting surface of the second holding member 3. The above-mentioned threaded hole 6 is situated on the ridge 20 of the second holding member.

The heights of the ridges 17, 20 are adapted in such a way that a gap is left between the respective flat surfaces 18, 19 of the two holding members.

By way of this preferred embodiment, the same tool can be used for extrusion of both the first and the second holding members with only one groove for clamping of one pipe. It is also possible to design the first holding member with several wedge-shaped grooves for clamping of one pipe each, and the second holding member with corre- sponding grooves with circle segment-shaped cross sections. The height of the ridge 11 of he first holding member 13 is so adjusted that the top surfaces of the ridges do not contact each other when a pipe with the intended cross-sectional area is centred.

The holding members are preferably manufactured from extruded aluminium, but they may also be manufactured from other materials and metals with comparable strength and weight properties.

The design of the pipe is shown in Fig. 3. The pipe 41 exhibits a circular cross section along a substantial part of the length of the pipe 41. The pipe further exhibits at least one area 40 with a deformed cross section. The area is delimited by first and second shoulder areas 42, 43, which are formed from the junction between the deformed zone and the non-deformed zone. The cross section of the deformed zone comprises a first area 44 with a wedge-shaped cross section, and a second area 45 with a circle segment- shaped cross section.

In a particularly preferred embodiment the pipe is deformed in connection with its mounting and fixation, which entails that the position of the deformation can be determined with great precision.

The invention is not limited to the embodiment that has been described above and shown in the drawing, but can be varied within the scope of the appended claims. For example, the second holding member may be designed equivalent with the first holding member, whereby the holder during use will surround a pipe to a high degree. Further, other locking members, different from the shown screw, may be used, such as an eccentric clamping member mounted on a shaft attached to the second holding member, whereby said eccentric member acts against the upper limiting surface 7 of the first holding member.

Claims

1) A device for fixation of a pipe, which device compπses a first and a second holding member (2, 3) which in a joined condition exhibit a recess (30) intended to at least partly enclose the pipe, and a locking member (4) for fixation of the holding members (2,3) to each other whereby a clamping of the pipe is achieved characterised in that said first holding member (2) exhibits a wedge-shaped groove (9) compπs- mg a first and a second flat lateral wall (11,12), intended duπng clamping of said pipe to contact two corresponding surfaces of the pipe, and that said second holding member (3) comprises a groove with a circle segment-shaped mantle surface (15) intended duπng clamping of said pipe to contact a corresponding surface of the pipe, whereby said wedge-shaped groove (9) is intended to achieve conical centπng of the pipe when this is clamped in said recess (30)

2) A device according to claim 1, characteπsed in that said locking member (4) compπses a guide, intended to guide the movements of the first locking member with respect to the second holding member duπng a clamping process of said pipe.

3) A device according to claim 2, characterised in that said guide allows the first holding member (2) to be moved at πght angles with respect to the second holding member (3)

4) A device according to any of the preceding claims, characteπsed in that said first and second holding members (2, 3) in joined condition exhibit two recesses, intended to at least partially surround one pipe each

5) A device according to claim 4, characterised in that said guide is positioned be- tween said recesses

6) A device according to any of the preceding claims, characteπsed in that said locking member (4) is constituted by a bolted joint connecting said holding members to each other.

7) A pipe and device for fixation of a pipe,

in which the pipe (41) exhibits a circular cross section along the major part of the length of the pipe and at least one deformed area (40) situated on the pipe between two shoulder sections (42, 43), said shoulder sections being formed by the junction between the deformed area and a non-deformed area,

in which the device comprises first and second holding members (2, 3) which in joined condition exhibit a recess (30) with a cross-section predominantly corresponding to the cross-section of the deformed area (40) of the pipe and an extension corresponding to the length of the deformed area of the pipe, whereby said recess (30) is intended to at least partly enclose said deformed area (40) and a locking member (4) for fixation of the holding members (2, 3) to each other, whereby clamping of the pipe is achieved,

characterised in

that the pipe exhibits in said deformed area (40) a cross section with on the one hand a wedge-shaped area (44) comprising first and second flat lateral surfaces and on the other hand a circle segment-shaped area (45) forming a surface with a circle segment-shaped cross section, whereby said first holding member (2) exhibits a wedge-shaped groove (9) comprising first and second flat lateral walls (11, 12), intended to contact, during clamping of said pipe, said flat surfaces of the pipe, and that said second holding member (3) comprises a groove with a circle segment-shaped mantle surface (15) intended, during clamping of said pipe, to contact the circle segment-shaped surface (45) of the pipe, whereby said wedge-shaped groove (9) is intended to achieve a conical centring of the pipe when it is clamped in said recess.

8) A pipe and device according to claim 7, characterised in that said locking member (4) is constituted by a bolted joint connecting said holding members to each other.

9) A pipe and device according to claim 7 or 8, characterised in that said first and second holding members (2, 3) are separated by a gap upon clamping of said pipe.