A BAND HAVING A HELICAL LINE FORM. AROUND CONDUITS.

TECHNICAL FIELD

The present invention relates to an arrangement for wrapping an elastic or resilient band having a helical line form around a multiple of conduits, and more speci¬ fically, but not exclusively, to an arrangement for wrapping an elastic band around a plurality of flexible conduits, where said band is intended to present a pre- shaped helical line form and therewith define a central¬ ly located cavity in which said multiple of conduits can be accommodated and which causes the conduits to be pressed against one another when the cross-sectional size of said conduits exceeds the cross-sectional size of said cavity within pre-determined limits.

The term conduits as used here and in the following includes electrical cables and flexible or bendable pipes and tubes, particularly such plastic pipes, hoses etc. , as those included in motor vehicle automatic lubricating systems and intended to conduct lubricant grease, when the engine of the vehicle is running, such as to ensure automatically that each lubricating point will receive precisely the amount of lubricant required at just the right moment in time.

The invention is described in the following with refe- rence to one such automatic lubricating system in which lubricant intended for lubricating bearing surfaces, journals etc. is delivered through resilient plastic pipes forming part of the lubricating system.

BACKGROUND PRIOR ART

With regard to the aforecited first technical appli¬ cation of the present invention, the Swedish Patent Application 8101920-0 teaches a yarn winding arrangement which when winding yarn taken from a storage reel by means of a spinner onto an electrical conductor bunch advanced through a central hole in reel, is effective in switching automatically to a fresh reel when the first reel is emptied of yarn or when the yarn breaks.

This publication thus teaches the possibility of winding yarn around a bunch of electrical conductors.

A similar arrangement can be said to be known from and described in the German Offenlegungsschrift 25 53 423 and the German Offenlegungsschrift 30 42 531.

These publications disclose that the yarn or band is wound onto a reel and that the reel is arranged for rotation around the conductors to be bound together.

It will be noted that these known arrangements do not utilize a band having a pre-formed helical line of curvature with a centrally located cavity into which a multiple of conduits are accommodated under pressure and held together by said wrapping.

SUMMARY OF THE PRESENT INVENTION

TECHNICAL PROBLEMS

When considering the present state of the art and also when considering the aforesaid technical fields it will be seen that a technical problem resides in the ability to use a band which presents a pre-formed helical curva- ture and therewith defines a centrally located cavity in

which said conduits can be received, preferably when the cross-section of said conduits exceeds the cross-section of the cavity, and therewith provide upstream of the location at which the band is wrapped around said con¬ duits, a simple device by means of which a helically curved band can be advanced and positioned adjacent said conduits, such as to enable the band to be readily placed around the conduits with the aid of rotary move¬ ment.

It will also be seen in connection with the aforesaid technical applications that a technical problem is one of realizing that a pre-formed, helically curved band or envelope must be led over a band guide means, immediate- ly prior to co-action of the band with the conduits, and that this guide means shall be operative to guide the band from a tubular or like-shaped member into wrapping engagement with the conduits.

Having provided a tubular or like-shaped member with enclosed helical band or envelope and, in conjunction therewith, having provided a band guide device operative to guide a band section around the conduits exiting from a tubular or like-shaped device a further problem resi- des in realizing that the two devices shall be arranged to rotate around said conduits.

By band section is meant here that section of a long, continuous band which constitutes one revolution of wrap around the conduits. A plurality of such sections wrapped in mutually sequential relationship thus form the band.

It will also be seen that a technical problem resides in realizing that a band having a pre-formed helical line

curvature and wound on a bobbin also needs to be rotated around the conduits.

It will also be seen that a particular technical problem resides in the realization that when a band having a pre-formed helical curvature is wound on a bobbin which is rotated about its centre axis and when the band is applied in the manner which solves the aforesaid techni¬ cal problems, it is necessary for the bobbin also to be rotatable about an axis which extends perpendicular, or substantially perpendicular to the aforesaid bobbin axis, so that rotation of the bobbin around the conduits during application of the band will not result in twist¬ ing of the band in the direction of the pre-formed heli- cal curvature.

It will also be seen that a technical problem resides in providing simple ways and means whereby flexible or bendable pipes intended for pressure lubrication pur- poses can be readily secured at one end by a first clamping device and can be secured at a distance from said first end by a second clamping device.

Another technical problem is one of realizing that conduits clamped in this manner should be subjected to a tensile force in the direction of longitudinal extension of said conduits when wrapping the pre-formed helical band therearound.

It will also be seen that when using a band which has a helical curved form, a technical problem resides in realizing that the tubular member used shall be arranged such as to form a particular angle with the conductor centre line and that this angle should be less than 45° and preferably greater than 10° .

It will also be seen that a further technical problem is one of providing a band guiding device of particularly simple construction and configuration. This problem can be solved in practice by forming the guide device from rigid wire or rod bent to an L-shape or to a U-shape.

A further technical problem resides in realizing that the use of a band having a pre-formed helical curvature necessitates, and enables, the tubular or like-shaped device and the band guide device to be arranged in a manner to form a carriage-like construction which is capable of being oveddisplaced along rails or guides extending in the direction of the longitudinal extension of the conduits, and that movement of the carriage can be effected through the coaction of one edge part of one band section with one edge part of an adjacent band section.

It will also be seen that a technical problem resides in the provision of a band guide device which although of very simple construction will nevertheless enable the device to generate frictional forces between the device and the belt, and that these frictional forces can then be utilized and modified such as preferably to slightly exceed the desired band tightening force around the conductors.

SOLUTION For the purpose of providing a solution to one or more of the aforesaid technical problems, the present inven¬ tion is based on an arrangement by means of which a resilient band can be fitted around a plurality of clamped, bendable or flexible conduits, said band being intended to present a pre-formed helical curvature and

therewith define a centrally located cavity for rec¬ eiving said plurality of conductors, even when, or particularly when, the cross-sectional area of said conductors exceeds the cross-sectional area of the cavity.

With a starting point from an arrangement of the afore¬ said kind, it is proposed in accordance with the present invention that, prior to being fitted around the conduc- tors, the band is advanced to a position adjacent said conductors, via tubular or like-shaped device; that immediately prior to co-action with the conductors, the band is passed over a band guide device operative to guide the band from the tubular or like-shaped device into wrapping or enveloping co-action with said conduc¬ tors; and in that the tubular or like-shaped device with the band enclosed therein, the band guide device and the conduit-embracing band section fed from the tubular or like-shaped device are rotated around said conduits.

As suitable embodiments supplementary to an arrangement of the aforesaid kind, it is proposed in accordance with the invention that the band having said pre-formed helical curvature is wound on a bobbin which can be rotated around said conduits.

In accordance with one advantageous embodiment it is proposed that the helically curved band is wound onto a bobbin which is rotatable about its centre axis and which can also be rotated about an axis which is a perpendicular or substantially perpendicular to said centre axis.

It is also proposed that the flexible or bendable con- duits are secured at one end by a first clamping device

and are further secured by a ^' second clamping device at a location spaced from said first end, said spacing pre¬ ferably being adjustable.

A tension force is preferably applied to the conduits in their longitudinal direction during a wrapping process.

It is also proposed that the tubular device is so arranged as to form an angle of less than 45° with a conduit centre line.

According to one advantageous embodiment the band guide device comprises an L-shaped or a U-shaped rigid wire or rod structure.

It is also proposed that, inter alia, the tubular or like-shaped device and the band guide device are arranged so as to form a carriage-like arrangement which is capable of being moved in the longitudinal direction of the conduits, and in that movement of the carriage is guided and effected through the co-action of one edge part of one band section with an edge part of an adjacent band section.

The band guide device is preferably positioned immedia¬ tely adjacent the conduits and is operative to generate a frictional force between the band and said device, this frictional force being intended to influence the band tightening force around the conduits.

ADVANTAGES

Those advantages primarily afforded by an arrangement according to the present invention reside not only in the possibility of readily fitting a band having a pre- formed helical curvature around a plurality of clamped,

flexible or bendable conduits, but also in the possibli- ty of readily forming conduit bunches with different numbers of conduits in separate conduit bunch sections and branches.

The main characteristic features of an inventive arran¬ gement are set forth in the characterizing clause of the following Claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of an arrangement at present preferred for wrapping a resilient band around a plurality of clamped conductors in a manner to form a conduit bunch with branches and its application in a central lubrica¬ ting system will now be described with reference to the accompanying drawings, in which Figure 1 is a perspective view of a vehicle incorpora- ting a central lubricating system utilizing a conduit bunch or bundle produced by means of the inventive arrangement,

Figure 2 illustrates one embodiment of a conduit bunch or bundle provided with suitable branches, Figure 3 is a side view, greatly simplified, of an arrangement for wrapping a pre-formed helical band around a plurality of conduits, and

Figure 4 illustrates in larger scale a tubular or like- shaped band feeding device and a band-guiding device located adjacent the conduits.

DESCRIPTION OF EMBODIMENTS AT PRESENT PREFERRED Figure 1 is a perspective view of a vehicle 1 equipped with a central lubricating system of known construction.

Thus, there is shown a lubricating system comprising a pump unit 2 operated pneumatically or hydraulically and having a fully sealed lubricant container.

Extending from the pump unit 2 is one (or more) main conduits 3, which may have the form of steel pipes or high pressure hoses and which extend to appropriately located branch points.

The main conduit 3 thus extends to a multiple of dis¬ tributor blocks provided with metering valves, of which one is referenced 4. The main conduit may have a con¬ struction which offers one to twelve metering valves of seven different sizes. Extending from the distributor block 4 are a plurality of flexible or bendable secon¬ dary conduits, which in the case of the illustrated embodiment are assumed to be nylon pipes (4 mm) or low- pressure hoses.

Each of these secondary conduits is intended to supply grease or lubricant to a particular bearing or journal, and several secondary conduits therefore extend in parallel through distances from one and the same dis¬ tributor block in the form of a so-called conduit bunch.

Figure 2 illustrates schematically a distributor block 4 provided with a plurality of metering valves, of which only two, 6 and 7, are referenced. A secondary conduit 8 extends from the metering valve 6 and a secondary con- duit 9 extends from the metering valve 7. Figure 2 also shows the locations to which these secondary conduits 8 and 9 extend (illustrated by the same reference nume¬ ral) .

As will be seen from Figure 2, the conduit bunch and its branches are wrapped in a band 10, the nature of which is described in more detail below, and given secondary conduits are branched-off at 11 to form a conduit bunch 12 while other secondary conduits form a conduit bunch 13.

The secondary conduit 9 is branched-off at 14, where it is wrapped in a band 10'.

A conduit bunch 16, which contains inter alia the secon¬ dary conduit 8, is branched-off at 15.

The present invention relates to an arrangement by means of which the pre-formed helical band 10 can be readily wrapped or placed around the conduit bunches, and where measures are taken to enable the branches to be produced in a simple fashion.

Figure 3 is a side view of an arrangement for placing a resilient band 10 around a plurality of clamped, bendable or flexible conduits, of which two are referen¬ ced 8,9.

By resilient band is meant that the band can be out¬ wardly flexed and not that it can be stretched or other¬ wise extended.

The band 10 is pre-formed to a helical curved configura- tion, such as to define a centrally located cavity in which a plurality of conduits are received, particu¬ larly, but not exclusively, conduits whose cross-sec¬ tional areas exceeds the cross-sectional area of the cavity.

It should be noted that the helical curvature of the band is preferably selected so that the centrally lo¬ cated cavity will obtain a cross-sectional area which is smaller than the cross-sectional area of the combined conduits, so that the band will automatically exert on the conduits a holding force generated by the force induced when tightening the resilient band.

Figure 3 thus illustrates an arrangement for producing a conduit bunch with branches, and includes a bobbin 30. The pre-formed helically curved band is wound onto the bobbin and one end of the band is then passed to and led through a tubular or like-shaped device 31.

Prior to being placed around the conduits 8, 9, it is necessary to advance the band 10, via said tubular or like device 31, to a position adjacent the conduits 8, 9.

Furthermore, immediately prior to being placed around the conduits 8, 9, it is necessary to pass the band 10 over a band guide device 32, which is operative to guide the band 10 from the tubular or like device 31 into enveloping co-action with the conduits 8, 9, as will be seen more clearly from Figure 4.

Referring back to Figure 3, it will be seen that the tubular or like device 31 with the enclosed band 10, the band guide device 32 and the band sections 10a, 10b, 10c exiting from the tubular or like device 31 and wrapped around the conduits 8, 9, are arranged to rotate around the conduits 8, 9, such as to wrap said band sections around said conduits.

The bobbin 30 is rigidly mounted on a rotatable plate 33 driven by a motor (not shown) and journalled in a frame 34 which co-acts, via a support 35, with a guide 36 arranged for movement along a guide 37. Consequently, it is necessary to rotate the bobbin 30 carrying the band 10 of pre-formed helical curvature around the conduits 8, 9.

Thus, the band 10 of helical curvature is wound onto a bobbin 30 which can be rotated about its centre axis 38 and which is also rotatable about an axis 39 located adjacent an extension of the device 31 and extending at right angles or approximately at right angles to the centre axis 38 of the bobbin. The band 10 is advanced to the device 31 in the direction of said axis 39.

The bobbin is mounted for rotation about its centre 38 such as to enable band section after band section to be unwound from the bobbin 30, so that the band sections will be wrapped around the conduits 8, 9 in sequence. The bobbin 30 is rotated about the axis 39 in order to prevent twisting of the band in the device 31 as a result of rotation of the plate 33 around the conduits, or conductors, 8 and 9.

All of the aforesaid flexible conduits 8, 9 are secured firmly at one end thereof by a first clamping device 40 and are also secured at a distance from said first end by a second clamping device 41. In the case of the illustrated embodiment, this distance can be adjusted.

It is proposed that a small tension force is applied to the conduits 8, 9 in the direction of their longitudinal axes, for instance by moving the second clamping device 41 to the right in Figure 3 while connected to said

conduits .

The tubular device 31 is intended to form an angle "a" with a central line of the conduits 8, 9. This angle will normally be smaller than 45° and larger than 10°, preferably between 20° and 30°, depending upon the material from which the band is made and the curvature of its helical form.

In the case of the Figure 4 embodiment, the band guide device 32 comprises a rigid rod bent into the shape of a U, although the device may also be L-shaped.

The band guide device 32 has a part 32a by means of which said device is attached to the tubular device 31. Extending at an angle from the part 32a is a part 32b which covers the central opening of the tubular device 31 at a distance therefrom.

The part 32c extends perpendicularly to the part 32b and is positioned in the extension of the device 31 such as to form the band guide device, and Figure 4 shows the band section 10b subsequent to having passed the part 32c and shows the band section 10c about to pass said part 32c. The part 32d, positioned at right angles to the part 32c, functions as an additional guide and may be omitted if desired.

Referring again to Figure 3, it will be seen that the tubular device 31 and the band guide device 32, together with the bobbin 30 and the element 33, 34, 35 and 36 form a carriage-like assembly which can be moved along one or more guides 37 extending parallel with the lon¬ gitudinal extension of the conduits 8, 9. It will also be seen that movement of the carriage along the guides

is effected and controlled by mutual co-action of one edge part 10a* ^* of a band section 10a wrapped around the conduits with an edge part 10b' of an adjacent band section 10b, as said band section 10b is placed around the conduits 8, 9.

It will also be seen that the band guide device 32, and then particularly the part 32c will generate a friction force between the device 32 and the band 10, the value of this force being dependent on the angle "a". The arrangement may be such that this frictional force is slightly smaller than the desired force by which the band is tightened around the conduits, or such as to exceed this tightening force.

The retaining and holding force will normally be depen¬ dent on a) the material from which the band 10 is made, b) the size of the conductors to be wrapped, and c) the cross-sectional area of the centrally located cavity prior to placing the band on the conductors, and is less dependent on the prevailing frictional force.

Since the aforesaid mutual co-action between the edge parts 10a' and 10b' engenders the force by means of which the carriage 50 is driven, it is preferred that the angular position of the guides 37, or of the arran¬ gement as a whole, can be adjusted in relation to the horizontal plane.

When the second clamping device 41 and the right-hand part of the guide in Figure 3 are lowered, a smaller force is required between the edge parts 10a' and 10 ' to move the carriage 50, whereas when the second clamp¬ ing device 41 and the right hand part of the guide 37 in Figure 3 are raised, a greater force between the edge

parts 10a' and 10b' is required to move the carriage.

It will be observed that the edge parts 10a' and 10b' illustrated in Figure 3 are displaced in relation to one another to a greater extent than would normally be the case. In practice, the edge parts 10a' and 10b' will lie close together.

In the manufacture of the conduit bunches, the band 10 is wound around all secondary conduits up to the part referenced 11. At this point, all secondary conduits intended for the conduit bunch 12 are cut into their respective lengths and bent to one side. The band, now referenced 10", is wound around the conduits up to the branch point 14, such as to form the wrapped section 13. At the branch or junction 14, the secondary conduit 9 is cut to the required length and bent or otherwise moved to one side, whereafter the procedure is repeated for all branches. All of the thus formed secondary conduits are wrapped in mutually the same manner.

Although not shown, the conduits 8, 9 may be supported and centered by means of some suitable device, for instance by means of an angle iron.

Means (not shown) can also be provided for raising and lowering the devices 31 and 32, in dependence on the thickness of diameter of the conduits.

The end of the tubular device 31 facing the bobbin 30 will preferably have a conical configuration, such as to receive the helically shaped band 10.

It will be understood that the invention is not restric- ted to the aforedescribed exemplifying embodiment there-

of, and that modifications can be made within the scope of the following claims.