EP0054007A1

EP0054007A1 - A tool for tightening and slackening large threaded parts such as tubes and the like

Info

Publication number: EP0054007A1
Application number: EP81830192A
Authority: EP
Inventors: Gino Passera; Bruno Sandei
Original assignee: Elettromeccanica Industriale Emi Di Sandei Bruno & C Sdf
Current assignee: Elettromeccanica Industriale Emi Di Sandei Bruno & C Sdf
Priority date: 1980-12-05
Filing date: 1981-10-12
Publication date: 1982-06-16
Also published as: IT8029064V0

Abstract

The invention relates to a tool for tightening and slackening of threaded parts or components, especially those of larger dimensions such as tubes, pipes etc., The tool basically comprises a cylindrical body (1), provided with a shank (2) serving to impart rotation thereto when paired with a conventional wrench or spanner; the cylindrical body shows an annular recess (6) within which one extremity of a chain (3) is permanently fixed, the other extremity remaining free.

The chain (3) is wrapped around the part or component to be tightened or slackened and its free extremity fastened to the cylindrical body at a point within the annular recess commensurate with the same's ability to grip the part/ component to be slackened.

By rotating the cylindrical body, torque is imparted through the chain to the component thus achieving the desired slackening off of the latter.

Description

The invention described herein is a tool for tightening and slackening threaded parts, -especially those having larger dimensions such as tubes, pipes etc.
The need for tightening or slackening of large threaded components such as wide-diameter tube, hydraulic reservoirs and so forth, is encountered not infrequently; furthermore these parts or components are invariably apt to be located in positions with little ease of access. Whether for the difficulty in laying hold of the part, or the difficulty in reaching it, the need arises for special kinds of tool.
Conventional tools in current use make use of flexible or articulated elements which wind around the part or component to be screwed tight or slackened; like tools are furnished with any one of a variety of devices which produce drag in the articulated or flexible element wound round the workpiece; the articulated or flexible element thus transmits torque to the part to be tightened or slackened, producing the desired screwing tight or unscrewing of the part or component itself.
It is often the case that such tools are unwieldy or awkward to use as a result of difficulty experienced in reaching the work.
One object of the invention herein is that of providing a tool for tightening or slackening large threaded parts which enables working on components out of easy reach or awkward to lay hold on.
A further object of the invention is that of providing a simple, inexpensive and compact tool. A further object of the invention is that of creating a tool which may be used in conjunction with others normally untilised by fitters/maintenance men.
These and other objects are attained to by the tool described herein which is characterised by the fact that it comprises: a cylindrical body provided with a shank which, paired with a conventional wrench/spanner of the appropriate size, allows for rotation of the cylindrical body around its own axis, to which the extremity of a chain is permanently attached in such a way that the axis of rotation relative to each link thereof lies parallel with the. said cylindrical body's axis; locking means designed for making the said chain fast to the said cylindrical body by any one of the individual links thereof.
Further features and advantages of the invention will emerge more clearly from the detailed description which follows of a preferred, though not exclusive form of embodiment of the tool described herein, illustrated as a strictly unlimited example with the aid of the accompanying drawings, in which:-

Fig 1 shows a vertical elevation of the tool to which the invention refers, in that position wherein one extremity only of the chain is attached to the cylindrical body of same;
Fig 2 shows a vertical elevation of the tool described herein, in that position wherein the chain thereof is wrapped around the work to be tightened or slackened, the latter illustrated only in part;
Fig 3 shows a cross-section according to III-III in fig 2, illustrating the tool to which the invention refers engaging a part or component to be tightened or slackened.

The tool described herein comprises a cylindrical body 1 provided with a shank 2; the shank 2 may be any one of a variety of types viz.-prismatic with square./ hexagonal cross-section, or splined or similar, and, paired with a conventional spanner/wrench of correct size -which needless to say must be of corresponding cross-section to the shank- furnishes the means for causing the cylindrical body 1 to rotate around its own axis. The wrench in question clearly could be a box-spanner, socket wrench or any other kind. The lateral surface of the cylindrical body is given axially-disposed knurling, for reasons which will become apparent hereafter.
The cylindrical body 1 comprises a cylindrical mid-section 5 of a lesser diameter than that of the body 1 as a whole, being defined by an annular recess 6 located in the cylindrical body 1 itself.
One extremity of a chain 3 is permanently attached to the cylindrical body 1 and disposed in such a way that the axis of rotation of each link thereof lies parallel with the cylindrical body 1 axis; provision is made for attachment of the chain extremity to the cylindrical body by means of a first pin 7 threaded through the end-link of the _"said chain itself and fixed permanently to the cylindrical body; a second pin 8 fixed likewise to the cylindrical body 1 holds the end-link afore-mentioned hard against the cylindrical mid-section 5.
Pins 7 & 8 are disposed internally of annular recess 6 with axes parallel to that of cylindrical body 1; the extremities of pins 7 & 8 being bedded into the flank- walls of annular recess 6.
The tool described herein further comprises locking means designed for locking the chain 3 to the cylindrical body 1 by any one of its several links.
The locking means comprises a third pin 9 which may be inserted into or withdrawn from cylindrical body 1; to this end there is a hole 12 located in the lower section of the cylindrical body 1 which admits the introduction of the said third pin 9. The extremity of the pin 9 is threaded in order to be screwed into a further, second hole 13 located in the upper section of the cylindrical body 1.
As per pins 7 & 8, pin 9 is disposed with axis parallel to that of cylindrical body 1, being likewise positioned internally of annular recess 6; said pin 9 is disposed all but diametrically opposite to second pin 8.
The function of the tool thus described is as follows: Chain 3, having one extremity permanently fixed to cylindrical body 1 and one extremity free, is wrapped around the part or component to be tightened or slackened, for instance around a tube 10 as illustrated in Figs 2 & 3; chain 3 is then fastened to cylindrical body 1-in such a way as to maintain contact -to all intents and purposes- between cylindrical body and part/component; to this end one of the chain links is introduced into annular recess 6, whereupon pin 9 is inserted into holes 12 & 13 in such a way that the chain link introduced into annular recess 6 is lodged between pin 9 itself and cylindrical mid-section 5. In this manner pin 9 holds said chain link fast against cylindrical mid-section 5 thereby fastening chain 3 itself to cylindrical body 1.
It will be clear that, according to the size of the part or component to be tightened or slackened, links correspondingly nearer to or farther from that permanently fixed must be fastened to the cylindrical body 1; the surplus stretch of chain remains free, offering no hindrance to the tool's normal function. Cylindrical_.body 1 is then caused to rotate -in either direction- by means of an appropriate implement engaging shank 2; in response to said rotation chain 3 is obliged to wrap around cylindrical body 1 thus gripping tube 10 tightly and imparting torque thereto causing tightening up or slackening off of same. Once pressure exerted upon the wrench is relaxed following the rotation of cylindrical body 1, the body itself remains anchored to tube 10 by virtue of the afore-mentioned knurling on its lateral surface, thereby disallowing any sudden loosening of chain 3. Provision may therefore be made for the implement used in rotating cylindrical body 1 to engage shank 2 in such a way as to prevent its sudden wihdrawal therefrom; this may be achieved by a spring-loaded ball-catch, for instance, located on shank 2 which seeks out a countersink made in spanner or wrench, or by. any arrangement of grooves, splines etc located either on shank 2 or corresponding implement. In any event such means of engaging wrench and socket would b,e of the conventional kind.
Should a wrench be used of the kind which remains united to the tool, it will be possible -once the latter is safely.anchored to the tube 10- to position (if assembling) or extract (if dismantling) the tube without needing to lay hold thereon.
The special shape of the tool described thus allows its being used for tightening or slackening threaded parts or components in the most inaccessible of locations; in fact, dimensions of the tool are such that , being small, the tool may be applied to the workpiece in practically any position whatever, a fact which makes for ease of access with a wrench or spanner to the shank 2.
Numerous modifications of a practical nature may be applied to the tool design, -for instance the shank may be male or female to accommodate whatever kind of wrench, spanner or extension bar etc.- without straying from within the bounds of protection afforded to the basic concept as described above, and as claimed below.

Claims

1) Tool for tightening and slackening large threaded parts such as tubes etc., characterised by the fact that it comprises: a cylindrical body (1) provided with a shank (2) which, paired with a conventional spanner/wrench of appropriate size, allows for rotation of said cylindrical body around its own axis, to which the extremity of a chain (3) is permanently fixed in such a way that the axis of rotation of each individual link thereof lies parallel with said cylindrical body axis; locking means designed for locking said chain to said cylindrical body by any one of the links thereof.

2) Tool according to claim 1 characterised by the fact that the lateral surface of said cylindrical body is provided with axially disposed knurling.

3) Tool according to claim 1 characterised by the fact that said cylindrical body comprises a cylindrical mid-section(5)of lesser diameter than that of said body as a whole, and defined by an annular recess (6) located in said cylindrical body itself.

4) Tool according to previous claims characterised by the fact that one extremity of said chain is fixed permanently to said cylindrical body by means of a first pin (7) threaded through the end-link of the chain itself, and a second pin (8) which holds said end-link fast against said cylindrical mid-section; provision being made for a third pin (9) capable of withdrawal from said cylindrical body, designed to hold any single chain link fast against said cylindrical mid-section; said third pin and said cylindrical mid-section constituting the aforesaid locking means; said first, second and third pins being disposed internally of said annular recess with.axes parallel to that of said cylindrical body; said third pin being all but diametrically opposed with respect to the disposition of said second pin.