PIPE-LAYING TOOL
The present invention concerns a tool for use in laying pipes, as defined in the preamble to Claim 1.
At present, joining of drain, and other equivalent, pipes is mainly accomplished by pounding on one end of the pipe section that has to be joined, over an interposed block, e.g. with a sledge hammer. Installation of long and heavy pipes applying this method is cumbersome because as a rule such installation is done in trenches affording little space. The istallation work can be facilitated by Lising lubricants, whereby the pipe that has to be pushed in will slide more easily against the seals or packings in the other pipe.
Some kind of installation tools intended for producing said pipe joints are also known in prior art. In the reference CH 569,220 is disclosed a pipejoining means which is mainly intended to be used in lifting the pipes and directing them into proper position. With its aid, however, the pipes to be joined cannot be pressed so as to make them form a pressuretight joint, as is often indispensable.
The reference NO 136,627 discloses an accessory means for joining pipes. This, however, only concerns pipes provided with shoulders, and therefore no joining of common pipes, which are completely smooth at one end, is feasible with the aid of this means.
The pipe joining procedtires known in the art are particularly embarrassed by cumbersome, and heavy, work steps, which moreover require at least two working persons: one to hold the pipe ends in place, and another to hit one end of the pipe with some striking tool. The possibility of damage to the pipes as a result of the blows is another drawback.
The object of the invention is to eliminate the drawbacks mentioned. In particular, it is an aim
of the invention to provide a tool with the aid of which the installation of pipes of various sizes issuccesfully managed, using one and the same tool, in cramped spaces even by one pipe-layer alone and with minor exertion. It is likewise an object of the invention to provide a means with the aid of which damage to the pipes at the installation stage is prevented.
Regarding the characteristic features of the invention, reference is made to the Claims section. The installation tool of the invention comprises a body, consisting of two elongated and relative to. each other movable, preferably telescopically relative to each other moving parts, of a power means for moving said parts relative to each other, and of a fixing member with the aid of which the pipes that have to be joined can be firmly connected to said partsfor the duration of the pipe-joining operation.
The parts of the body are advantageously tubular parts with round or angular cross section and movable relative to each other, one within the other, in which case moving of the parts relative to each other may be accomplished with a crank handle and shaftattached to one of the parts and a wire rope attached to the other part. It is equally possible to use for power means various helical thread structures operated with a crank. Various power machines may also be contemplated, such as for instance the moving of the parts relative to each other with the aid of a hydraulic cylinder. The fixing member advantageously consists of a strap assembly comprising straps, webbing or equivalent to be affixed to the parts of the body, and securing means provided on these. Hereby the elastic, and long enough, strap can be tightened around the pipe in every instance, independent of the pipe diameter. Attachment of the strap to the body parts may be by one or several attachment eyes, and it may run
around the body part. It is also possible to use for fixing members, various jaw and grab structures which are attached to the body parts and operate manually or by mechanical means. The tool of the invention further comprises, advantageously, bracing chocks on the body parts, these chocks bracing the tool against the pipes which are being manipulated. The chocks may be integral parts of the body parts, or they may be separate parts affixed to the body parts. In an advantageous embodiment, one or several of the chocks are pivotally attached to the body parts, e.g. with a shaft or ball pivot, in which case the chock will bend to conform to the surface configuration of the pipe. On the lower faces of the chocks, that is on the faces coming to lie against the pipes, one may use various costings, e.g. rubber, serving to increase the holding power. Likewise , various materials increasing the holding power may be applied on the parts; of the fixing member coming into contact with the pipes.
The advantage of the invention over the state of art is above all seen in the achieving of an easy, simple and fast pipe-joining procedure by using the tool of the invention. Another advantage is the reduced number of installation worlers required, and significant reduction of the livelihood of pipe damage. In addition, the means of the invention may also be applied when detaching pipe sections from each other.
The invention is described in detail in the following, referring to the drawings, wherein:
Fig. 1 presents a pipe installation tool according to the invention,
Fig. 2 presents another pipe installation tool according to the invention, Fig. 3 presents a third embodiment of the invention, and Fig. 4 presents a tension means for use in the means
of the invention.
One pipe installation tool according to the invention, depicted in Fig. 1, comprises a body 1 consisting of two elongated and relative to each other telescopically movable parts 2, 3. On each part have been affixed two bracing chocks 4, which rest against the pipes that are being joined over rubber pads 16. Bearings 15 have been provided between the tubular parts 2 and 3, ensuring effortless movement of the parts relative to each other.
On one end of the part 2 belongs a power means 7, consisting of a jointed shaft 8 and a crank handle 9 affixed to the shaft. One end of a wire rope 10 has been fixed to the shaft 8 and the other end, to the part 3, the wire running within the tubular parts 2, 3. Thus it becomes possible to pull the parts 2 and
3 into each other by turning the crank handle 9.
In addition, the parts 2 and 3 comprise fixing members 17, which consist of straps 6 of an elastic material and of securing means 5 belonging to these straps. The straps have been attached to the parts 2 and 3 by passing then through eyes 18 provided on said parts.
In Fig. 2 is depicted another pipe installation tool according to the invention, which is mainly consistent with the embodiment of the invention shown in Fig. 1. The difference is that the bracing chocks
4 are pivotal ly attached to the parts 2 and 3 and that no separate slide bearings have been inserted between the parts 2 and 3, instead of which these parts slide along each other's surfaces, and that the power means 11 presents a different design. The power means 11 comprises a threaded rod 12 with a crank handle 14 connected to one end thereof, to enable the rod to be rotated. The threaded rod 14 carries threads 19 cooperating with the threads within a sleeve 13 provided in the part 3. Thus, by rotating the threaded rod 12
the sleeve 13, and the part 3 along with it, will move relative to the threaded rod and to the part 2. It is thus understood that the power means 11 can be used to move the parts 2 and 3 relative to each other in either direction.
In Fig. 3 is depicted a tool according to the invention having no fixing members, this tool comprising, in addition to the cranl handle-and-shaft assembly of Fig. 1, another similar cranl handle-and- shaft assembly 20 intended for pulling out the means, whereby the means operating with wires or straps may also be used to disassemble joined pipes. In this case, the shaft of the assembly 20 is rotatably carried in the outer part 2 and the inner part 3 has been provided with elongated slits 21 for enabling the parts to be moved relative to each other. The shaft 20 may also serve as deflection sheave, in which case it requires no craril handle. In that cas e, the wire 10 runs around the shafts 8 and 20 and has been attached to the part 3; turning tine crank handle in different direction will then enable pipe joining as well as pipe disassembly to be accomplished.
The pipe installation tool of the invention, depicted in the figures, operates as follows. The pipes that have to be joined are placed end to end so that the ends to be joined are in register, preferably alreadv pushed into each other a short distance, as shown in the figures. The tool is positioned upon the pipes so that one part 2 is braced with the bracing chocks 4 against one of the pipes to be joined and the other part 3 is braced with the bracing chocks 4 against the other pipe to be joined. The parts 2 and 3 have been pulled out to be only a short distance within each other. The straps 6 are then clamped as tightly as, possible around the pipes, to connect the parts 2 and 3 firmly to the pipes. Hereafter, turning the crank handle 9 or cranl handle 14 will cause the parts
2 and 3 to be pushed into each other, resulting in even stronger tightening of the straps around the pipes so that the straps pull the pipes into each other at the point of juncture, in desired manner. In the advantageous embodiments of Figs 2 and 3, the operation just described can be inverted, whereby disassembly, of a pipe joint is accomplished in like manner and with equal ease.
In one embodiment of the invention, the fixing means comprises in addition to a strap structure and securing means, also tension means by the aid of which the straps, secured around the pipe, can be drawn taut.
In Fig. 4 is depicted a tensioning means attached to a tool according to the invention, both in its opened and its closed position. The tension means comprises an elongated lever 22 pivotally connected by one end to the part 2 or 3. The lever carries on its end adjacent to the pivot, two pins 23 parallelling the pivot axis and placed side by side, the strap 6 affixed by one end to the part 2 or 3 being placeafole to run around the pipe, over the upper pin and down between the pins to be substantially taut. When hereafter the lever 22 is swung the topside way (arrow 24), the strap will be wound around the pins and it will be drawn taut around the pipe. Furthermore, the lever has been pivotally attached to the part 2 or
3 of the tool in such manner that it can be turned to lie parallel to the body of the tool when not in use. The invention has been described in the foregoing, referring to certain advantageous embodiments of the invention. However, these are not in any way restrictive on the invention: different embodiments of the invention may vary within the inventive idea set forth in the claims.