GB2234795A

GB2234795A - Tube with connector for vacuum cleaning equipment

Info

Publication number: GB2234795A
Application number: GB9017472A
Authority: GB
Inventors: Michael Edward Gailes; Christopher Robert Duncan
Original assignee: Numatic International Ltd
Current assignee: Numatic International Ltd
Priority date: 1989-08-10
Filing date: 1990-08-09
Publication date: 1991-02-13
Anticipated expiration: 2010-08-09
Also published as: GB8918286D0; GB2234795B; GB9017472D0

Abstract

A conduit member comprising a tubular element which has a first end and a second end, said first end being adapted to receive the second end of an identical tubular element, and a collar which is adapted to be carried on said first end of the tubular element to provide a soft-feed of one tubular element into another; characterised in that the tubular element is unperforated, and, in the fitted position, the collar is securely retained on the first end of said tubular element.

Description

VACUUM CLEANING EQUIPMENT This invention relates to accessories for vacuum cleaning equipment and has particular reference to connectable conduit members therefor.

Typical vacuum cleaning equipment comprises a body housing a suction motor and providing a receptacle for the collection of dirt and dust, a flexible hose connected to said body, a rigid conduit portion connected with said hose and adapted to carry one or more cleaning tools at an end thereof. In many vacuum cleaners, in particular heavy duty vacuum cleaners, the conduit portion typically comprises a number of rigid tubular members made from stainless steel, mild steel or aluminium tubes. Each tube may be provided with a plastic collar at one end and may be tapered at the other end, the arrangement being such that the tapered other end of a first tube is adapted for insertion into the collared one end of a second tube.

The purpose of the collar is to create a "soft feed" of the tapered other end of the first tube into the collared one end of the second tube and to finish the annulus at the one end of the second tube by making the tube look more attractive to a customer.

Such a collar typically has a rim portion, which is arranged to overlay the annulus at the one end of the tube, and a cylindrical body which overlays said one end portion of the tube and is fixedly secured thereto. In tubes as currently produced, this is done by providing a number of spigots, typically three, on the inner cylindrical surface of the cylindrical portion of the collar, and providing corresponding holes in the steel tube; the collar is fitted to the tube by aligning the spigots with the holes, and then force fitting the collar to the one end of the tube to obtain the necessary interengagement.

It will be appreciated by the man skilled in the art that the manufacturing tolerances of such an arrangement are costly to achieve. Furthermore, since the collars are manufactured by injection moulding, the moulds for manufacturing the collars are complex and, if three spigots are used, the mould requires three fingers which form the inner surface of the cylindrical portion, including the spigots. Since each of these fingers has to be withdrawn from the collar once it has been moulded in order to release the collar so formed from the mould, the rim portion of the collar must be discontinuous to allow removal of the fingers. This spoils the appearance of the tube and results in a poor seal because air can pass through the discontinuities in the rim when one tube is inserted into another. Furthermore, such collars are difficult to remove from the tubes once they have been fitted.

According to one aspect of the present invention, therefore, there is provided a conduit member comprising a tubular element having a first end and a second end, said first end being adapted to receive the second end of an identical tubular element; and a collar, adapted to be carried on said first end of the tubular element to provide a soft-feed of one conduit member into another; characterised in that the tubular element is unperforated and, in the fitted position, the collar is securely retained on the first end of said tubular element.

According to another aspect of the present invention there is provided vacuum cleaning equipment, comprising a receptacle, conduit means in fluid communication with said receptacle, and suction means adapted to draw detritus and dust through the conduit means and into the receptacle, wherein said conduit means includes at least one conduit member which comprises a tubular element adapted at a first end to receive an end of an identical conduit member, and at a second end to enter into a receiving first end of another identical conduit member, said conduit member including a collar adapted to fit on the first end of the tubular element to provide a smooth feed of one conduit member into another; characterised in that said tubular element is unperforated and said collar is retained on the first end of the tubular element.

By using an unperforated tubular element instead of a perforated tubular element, one stage in the manufacturing process of the conduit member may be eliminated. Furthermore, an unperforated tube is stronger than a comparable perforated tube.

Each of the first and second ends of the tubular element terminates in an annulus and, in one embodiment of the present invention, the collar may comprise a generally cylindrical sleeve adapted to overlay the first end of said tubular element and having a generally cylindrical inner surface, and an annular flange such that, when the collar is in the fitted position, the flange extends over the whole of the annulus at the first end of the tubular element.

The collar may be secured to the first end of the tubular element by the use of an adhesive.

According to another aspect of the present invention, there is provided a conduit member wherein the internal cylindrical surface of the cylindrical sleeve of said collar defines a recess or abutment, and the first end of the tubular element defines a rib or bead which is interengageable with said recess or abutment, whereby the collar is physically retained on the first end of the tubular element by means of the interengagement of the rib or bead on the tubular element and the corresponding recess or abutment on the collar.

In an alternative embodiment, the first end of the tubular element may define a continuous circumferential abutment or a continuous groove and the internal surface of the cylindrical sleeve of the collar may define a corresponding interengagable abutment or groove, the collar being configured to snapfit onto the first end of the tubular element and being held there by the abutment or groove.

Preferably the second, uncollared, end of the tubular element is tapered for insertion into the collared first end of a tubular element of a second conduit member. Alternatively, the collared end of the tubular element may be flared and the uncollared end of the second conduit member may be cylindrical. In yet a further embodiment, the collared end may be flared and the uncollared end tapered.

The tubular element may be made from stainless steel, mild steel, aluminium or from a number of other alternative suitable materials which are well known to a man skilled in the art. In a preferred embodiment of the present invention, however, the tubular element is made of stainless steel and the collar is made of a low density plastics material such as low density polyethylene.

In some embodiments of the present invention, the rim portion of the collar may serve to finish the tubular element and to smooth the feed of the second end of a one tubular element into the first collared end of a second tubular element.

In some embodiments, the collar may provide a generally airtight seal between said first and second tubes. Further, in some embodiments of the present invention, the rim portion of the collar may protect both tubular elements from being scratched or damaged when the second end of the one tubular element is inserted into the collared first end of the second tubular element.

A further advantage of some embodiments of the present invention is that the collar may be readily detached from the first end of the tubular element by using a suitable tool.

While the invention is described with reference to connectable conduits for vacuum cleaners, it will be clear to the man skilled in the art that the invention relates to the field of rigid connectable conduits generally.

The following is a description by way of example only and with reference to the accompanying drawings of carrying the invention into effect.

In the drawings: Figure 1 is a longitudinal section through a portion of each of two conduit members.

Figure 2 is a longitudinal section through a portion of a different conduit member.

Figure 3 is a longitudinal section through a portion of a second different conduit member.

Figure 4 is a longitudinal section through a portion of a third different conduit member.

A conduit member indicated generally at 10 consists of an elongate cylindrical tube 11 which terminates at a first end 12 in a receiving female portion 13 and at a second end 20 in a frustoconical male portion 19.

Receiving portion 13 includes a frustoconical portion 14 which flares outwardly towards first end 12 to terminate in a cylindrical end portion 15 having a diameter larger than that of tube 11. Said end portion 15 is further radially expanded towards first end 12 to provide an annular flange step 17, and terminates at end 12 in an end edge 18.

Cylindrical end portion 15 is adapted to carry a collar 30 having a generally cylindrical body part 31 adapted to overlay said cylindrical end portion 15, and an inwardly directed annular flange 34 adapted to overlay said end edge 18 of tube 11. Flange 34 has an inner edge 37 which is inwardly tapered in a direction towards the interior of tube 11.

Cylindrical body part 31 terminates remote from flange 34 in a second end 40 and has an internal surface 32 which carries towards said second end 40, a circumferential, inwardly-directed bead 41. Internal surface 32 then tapers outwardly and away from bead 41 to provide a substantially frustoconical surface 39 which terminates at second end 40 in an annulus 42, such that frustoconical surface 39 is entered over first end 12 of tube 10, and is urged thereonto until bead 41 enters or "snaps over" step 17 thereby retaining collar 30 securely on the end of tube 11.

In this way, collar 30 is securely fastened to receiving portion 13 of tube 11, so that flange 34 overlays the whole of the end edge 18 of tube 11.

Receiving female portion 13 of a first conduit member 10 is adapted to receive the frustoconical male portion 19' of an identical second conduit member 10', such that said male portion 19' is entered coaxially into cylindrical end portion 15, thereby dilating flange 34, and is urged thereinto until frustoconical male portion 19' abuts the interior surface of frustoconical portion 14 of receiving female portion 13.

Second conduit member 10' is thereby securely held in fluid communication with first conduit member 10, and flange 34 of collar 30 forms a relatively air-tight seal around tube 11' towards second end 20'.

Figures 2, 3 and 4 show different embodiments of the present invention and, where appropriate, the same reference numerals as Figure 1 have been used.

In Figure 2, the cylindrical end portion 15 of tube 11, intermediate annulus 18 and frustoconical portion 14, is provided with a circumferential, outwardly directed rib 50 having an arcuate cross-section.

Internal cylindrical surface 32 of sleeve 31 of collar 30, intermediate flange 34 frustoconical surface 39, is provided with a circumferential outwardly directed recess 51 of generally arcuate cross-section, said recess being adapted to receive said rib 50 to retain said collar 30 securely in the fitted position on receiving female portion 13 of conduit member 10.

In Figure 3, collar 30 is fixedly attached to end portion 15 of tube 11 by means of an aadhesive disposed between said collar 30 and receiving portion 13 of conduit member 10.

In Figure 4, cylindrical end portion 15 of conduit member 10, intermediate annulus 18 and frustoconical portion 14, defines a circumferential, inwardly directed recess 60 of generally arcuate cross-section.

Inner cylindrical surface 32 of collar 30, intermediate flange 34 and frustoconical surface 39, defines an inwardly directed circumferential bead 61 of generally arcuate cross-section, which, when collar 30 is fitted over end portion 15, is adapted to "snap-fit" into recess 60, thereby fastening said collar 30 securely to said tube 11.

Claims

1. A conduit member comprising a tubular element which has a first end and a second end, said first end being adapted to receive the second end of an identical tubular element, and a collar which is adapted to be carried on said first end of the tubular element to provide a soft-feed of one tubular element into another; characterised in that the tubular element is unperforated, and, in the fitted position, the collar is securely retained on the first end of said tubular element.

2. A conduit member as claimed in claim 1 characterised in that the collar comprises a generally cylindrical sleeve having at one end an annular flange adapted to overlay an end edge of said element.

3. A conduit member as claimed in claim 1 or claim 2 characterised in that said collar comprises fastening means adapted to engage cooperating means disposed on said first end of the tubular element to securely attach said collar thereto.

4. A conduit member as claimed in any preceding claim characterised by a rib or bead provided on one of said collar or said tubular element, and a cooperating recess or abutment provided on the other of said collar and said element and adapted to receive said rib or bead.

5. A conduit member as claimed in claim 4 characterised in that said collar has a circumferential bead adapted to engage with a cooperating circumferential step on said element whereby on entering the collar over the said first end of the tubular element the bead engages with said step to prevent removal of said collar therefrom.

6. A conduit member as claimed in any preceding claim characterised in that said collar comprises an annular flange adapted to cooperate with the second end of an identical tubular element received by said first end to form a generally airtight seal therebetween.

7. A conduit member as claimed in any preceding claim characterised in that said flange is continuous.

8. A conduit member as claimed in any preceding claim, characterised in that said collar is securely fastened to said tubular element by an adhesive disposed between said collar and said element.

9. A conduit member constructed and arranged substantially as described herein with reference to and as shown in Figure 1, in Figure 2, in Figure 3, and in Figure 4 of the drawings.