Field of the Invention

The invention relates to pipe clamps.

Background of the Invention

Polypropylene (PP) pipes and fittings include a pipe section and a female pipe end intended for tight sliding insertion of a pipe end of a pipe section to form a sealed pipe joint. The female pipe end has an end surface and an annular seal housing for housing an annular seal for sealing engagement with the pipe end inserted therein. Drainage pipes can be joined end to end. Drainage fittings include inter alia L-shape drainage fittings, T-shape drainage fittings, double branch fittings, double corner branch fittings, and the like.

Construction standards preclude the use of PP pipes and fittings in concrete constructions for waste water drainage purposes, rainwater drainage purposes, ventilation purposes, and the like, due to two concerns regarding the integrity of a sealed pipe joint as follows: First, the sealed pipe joint is considered as being insufficiently robust to withstand stresses arising in concrete constructions. And second, the hydration process of concrete is considered to negatively impact on the seal's sealing ability.

There is a need for a pipe clamp for ensuring a sealed pipe joint meets construction standards.

Summary of the Invention

The present invention is directed toward a pipe clamp including a clamp member and a clamping device. The clamp member has a longitudinal axis and a stepped tubular construction including a leading clamp member section and a trailing clamp member section. The leading clamp member section includes at least two snap fit members for snap fitting on an annular seal housing on telescopically sliding the pipe clamp onto a female pipe end. The trailing clamp member section is intended for initial sliding insertion of a pipe end therethrough for sliding insertion into the snap fitted female pipe end and subsequent tightening on the pipe end by the clamping device for inwardly radially urging a sharp teeth arrangement encircling the longitudinal axis and facing theretoward to penetrate the pipe end. The clamp member sections are preferably corresponding provided with a leading clamp member seal and a trailing clamp member seal such that the pipe clamp forms a sealed cavity preventing the female pipe end's seal being wetted during a hydration process of a concrete construction.

The pipe clamp of the present invention secures a hitherto described sealed PP pipe joint to meet construction standards for use in concrete constructions for waste water drainage purposes, rainwater drainage purposes, ventilation purposes, and the like. Accordingly, PP pipes and fittings can replace presently installed High Density PolyEthylene (HDPE) pipes and fittings which employ butt welding for joining purposes.

The pipe clamps of the present invention are also suitable for use with

PVC, HDPE, and other plastic pipes and fittings. The pipe clamps can be provided in different diameters and geometries to match pipe ends and female pipe ends. Brief Description of Drawings

In order to understand the invention and to see how it can be carried out in practice, a preferred embodiment will now be described, by way of a non- limiting example only, with reference to the accompanying drawings in which similar parts are likewise numbered, and in which:

Fig. 1 is a pictorial view of a pipe clamp including a clamp member and a clamping device for use with a pipe end and a female pipe end;

Fig. 2 is an exploded perspective front view of the pipe clamp;

Fig. 3 is a top plan view of the clamp member;

Fig. 4 is a longitudinal cross section of the clamp member along line A- A in Figure 3;

Fig. 5 is a close up view of an encircled area denoted A in Figure 4; Fig. 6 A is a side elevation view showing the pipe clamp mounted on a female pipe end;

Fig. 6B is a longitudinal cross section along line B-B in Figure 6A;

Fig. 6C is a side elevation view showing a pipe end inserted into Figure 6A's pipe clamp;

Fig. 6D is a longitudinal cross section along line B-B in Figure 6C;

Fig. 6E is a close up view of an encircled area denoted D in Figure 6D prior to operation of the clamping device; and

Fig. 6F is a close up view of the encircled area denoted D in Figure 6D subsequent to operation of the clamping device for radially inward urging teeth to penetrate into a pipe end.

Detailed Description of Drawings

Figure 1 shows a pipe clamp 100 for use with a pipe end 10 for tight sliding insertion into a female pipe end 20 to form a sealed pipe joint. The female pipe end 20 has a stepped tubular configuration and includes an end surface 21 and an annular seal housing 22 for housing a seal 23 (see Figure 6B) for sealing engagement with the pipe end 10 on sliding insertion of the pipe end 10 therein. The female pipe end 20 extends to a pipe section 24 typically having the same diameter as the pipe end 10 against which the pipe end 10 abuts on its sliding insertion into the female pipe end 20. The pipe clamp 100 includes a clamp member 101 and a clamping device 102 constituted by a commercially available hose clamp manually operable to change its diameter. The hose clamp 102 includes a metal band 121 and a manual or screw driver operable worm gear arrangement 122 for changing its diameter.

Figures 2 to 5 shows the clamp member 101 has a longitudinal axis 103 and a stepped tubular construction including a leading clamp member section 104, a trailing clamp member section 106 and an intermediate clamp member section 107 joining the leading clamp member section 104 and the trailing clamp member section 106. The leading clamp member section 104 includes a multitude of six equispaced apart snap fit members 108 encircling the longitudinal axis 103 and facing theretoward for snap fitting on the annular seal housing 22 on sliding the pipe clamp 100 on the female pipe end 20. The leading clamp member section 104 can include more or less snap fit members 108 depending on a number of factors including inter alia pipe diameter, and the like.

The pipe clamp 100 includes a leading clamp member seal 109 between the leading clamp member section 104 and the intermediate clamp member section 107 for sealing contact with the female pipe end 20 on sliding the pipe clamp 100 thereonto. The leading clamp member seal 109 is preferably disposed to seal against an annular seal housing 22.

The trailing clamp member section 106 includes a sharp teeth arrangement 111 deployed around and facing towards the longitudinal axis 103 and intended to penetrate a pipe end 10 on tightening the hose clamp 102 to reduce the internal diameter of the trailing clamp member section 106 from an initial internal diameter to a final internal diameter. The trailing clamp member section 106 can be formed in a wide range of configurations enabling reduction of its internal diameter on tightening the hose clamp 102. The sharp teeth arrangement 111 can be formed in a wide range of implementations suitable for penetrating a pipe end 10 on reduction of the trailing clamp member section 106's internal diameter.

The trailing clamp member section 106 includes six spaced apart teeth support members 112 encircling the longitudinal axis 103 and intended for initial sliding insertion of a pipe end 10 therethrough for sliding insertion into a female pipe end 20. The trailing clamp member section 106 can include more or less teeth support members 112 depending on a number of factors including inter alia pipe diameter, and the like. The teeth support members 112 each have a base 113 connected to the intermediate clamp member section 107 and adjacent teeth support members 112 define longitudinal directed T-shaped apertures 114 therebetween. The T-shaped apertures 114 each include an elongated peripheral slot 114A between the bases 113 of adjacent teeth support members 112 and an elongated axial directed slot 114B between adjacent teeth support members 112. The width of the elongated axial directed slots 114B between adjacent teeth support members 112 is reduced on operation of the clamping device 102 to reduce the trailing clamp member section 106's internal diameter. The teeth support members 112 are each formed with five axial directed slots 116.

The sharp teeth arrangement 111 is formed from three peripheral radial inward directed ridges 117 staggered along and encircling the longitudinal axis 103. Each ridge 117 is interrupted by the axial directed slots 114B and the axial directed slots 116 to form a multitude of sharp teeth 118. The trailing clamp member section 106 can include more or less ridges 117 depending on a number of factors including inter alia pipe diameter, pipe material, and the like.

The pipe clamp 100 includes a trailing clamp member seal 119 between the trailing clamp member section 106 and the intermediate clamp member section 107 for sealing contact with the pipe end 10 on its insertion therethrough for sliding insertion into a female pipe end.

The use of the pipe clamp 100 is now described with reference to Figures 6A to 6F as follows:

Figures 6 A and 6B show the pipe clamp 100 telescopically mounted on a female pipe end 20. The snap fit members 108 are snap fitted on the annular seal housing 22. The leading clamp member seal 109 is in sealing contact with the annular seal housing 22.

Figures 6C and 6D show the pipe end 10 slidingly inserted through the trailing clamp member section 106 for sliding insertion into the snap fitted female pipe end 20 until it stops against the pipe section 24. The trailing clamp member seal 119 is in sealing contact with the pipe end 10.

Figure 6E shows teeth 118 prior to operation of the hose clamp 102 spaced apart from the pipe end 10' s peripheral surface.

Figure 6F shows the teeth 118 penetrating the pipe end 10 subsequent to being urged radially inward by operating the hose clamp 102 to tighten the trailing clamp member section 106 thereby peripherally compressing the teeth support members 112 towards one another.

The leading clamp member seal 109 and the trailing clamp member seal 119 form a sealed cavity preventing the female pipe end's seal 23 being wetted during a hydration process of a concrete construction.

While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications, and other applications of the invention can be made within the scope of the appended claims.