GB2300687A

GB2300687A - Vibration insulation device

Info

Publication number: GB2300687A
Application number: GB9509685A
Authority: GB
Inventors: Robert Cartwright Harrison
Original assignee: PLANTRAGG DEVELOPMENTS
Current assignee: PLANTRAGG DEVELOPMENTS
Priority date: 1995-05-12
Filing date: 1995-05-12
Publication date: 1996-11-13
Also published as: GB9509685D0

Abstract

A vibration insulation device comprises a mechanical means of containing and reinforcing a bushing 7 of resilient flexible laminated, honeycombed, composite, foamed rubber or plastics so as to provide a very flexible mounting for a high energy source of vibration fixed to a foreplate 2 and so be fitted between said source and a highly stressed supporting structure 5 to protect said structure from harmful vibration and metal fatigue.

Description

VIBRATION 'NS'ULATION DEVICw The present invention relates to a device for the reduction of vibration in the method of suspension of a vibrating source and to the use of such a device in dislodging materials adhering to upwardly extending surfaces.

Concrete breakers, pneumatic drills and like machines create violent and high frequency vibrations. This makes them unsuitable for use in conjunction with supporting machinery of the kind which is highly stressed, for instance because of the lever type of forces acting on it.

Similarly if a source of high energy vibration is held fixed against a rigid immoveable surface without recoil energy being able to escape, the source of vibration will self destruct.

The present invention provides a simple inexpensive damping device which when positioned between a source of vibration and a fragile or highly stressed supporting structure for the said source of vibration, shields the structure from damaging vibrations and allows the vibrator to be flexibly held against an immoveable object such as the steel side of a ship. Accordingly the present invention is for a vibration insulation device comprising of flexible material in the form of bushing, a source of vibration and a supporting structure, in the form of a boom, for the source of vibration, said source of vibration and said boom being connected to said vibration insulation device n such a way that said device damps the transmission of vibrations from the said source of vibrations to the said boom.

The present invention also relates to a solid mass of resiliently flexible material clamped between the source of vibration and the supporting structure in the form of a boom or the source of vibration.

In one embodiment of a vibration insulation device as described above the boom comprises of an extending arm. The extendible arm may be connected to a mobile power source such as a tractor, with the extendible arm adapted to be moveable about an axis.The source of vibration is attached to the extremity of the arm through an intermediary vibration insulation device of the k nd according to the present invention.

The source of vibration may be a concrete breaker. Concrete breakers usually have chisel type ends. If instead of a chisel type end there is substituted a blunt or hammer type head, such a device may be used to impart vibrations to a vertical or upstanding surface thereby to dislodge any material loosely adher ing thereto. Alternatively the concrete breaker can be fitted with a cup into which is fixed a log of wood instead of a steel hammer head which will still transmit vibration to a ship but without harmful effects of metal to metal impact.

In a further embodiment of the invention therefore, there is provided a process for removing materials adhering to upwardly extending surfaces which comprises imparting vibrations to the surface using the combination described above. For example material such as damp coal, urea, chemical salts or ores when transported in the hold of a ship, tends to be compressed between the stringers in the side of the hold and hence forms a mass which is difficuit-to dislodge. In the past this mass has been removed manually by prodding with a rod or a pole or digging with a spade, an expensive and time consuming affair.

In contrast the method envisaged by the process of the present invention results in the rapid decent of all the adhering materials in a short space of time using only one machine Moreover, in a still further embodiment of the invention, mortar bonded structures such as buildings are demolished by a process which comprises imparting vibrations to the structure using the device described above.

The present invention is illustrated in the accompanying drawings in which FIGURE 1 is a part side sectional elevation of a vibration insulation device with resiliently flexible material clamped between the two support faces assisted by spring or gas filled cylinders and pistons. The flexible material could be a foam filled tyre.

FIGURE 2 is an exploded sectional view of bushings of resilient flexible material (shaded) which when assembled and locked together allow the back plate with a quick fit hook and lug to suspend a source of vibration on the foreplate without metal to metal contact and so utilize the insulation benefit of the flexible material. Any number of bushings and clevis fittings can be employed to join the bacplate and foreplate, all with flexible bushings eliminating metal to metal contact.

FIGURE 3 is a side elevation of a tractor unit incorporating a device according to the present invention.

FIGURE 4 is a part sectional drawing of a device utilizing resilient lexible bushing but arranged differently to that shown in figure 2 Referring to figure 1 of the. drawings there is illustrated in outline a mounting lug 1 with holes to recieve a source of vibration which is fixed to a foreplate 2. (shown in section)onto which is bolted pistons 3 and through which passes clamping bolts 4. 3ackplate 5 is a 'quicit' attachment or mounting to a boom or means of support to the whole assembly through which passes clamping bol-ts 4. On the backplate 5 is also fixed cylinders 6 which contain double acting pistons 3.The pistons 3 can be restrained on both sides in the cylinders by pressurised gas or equal balanced springs. 7 is a flexible block of elastic type material which absorbs the recoil or bouncing effects or the vibration source rather than passing the harmful vibrations into a slender support boom. 7 can also be substituted by a foam filled tyre Referring to figure 2 of the drawing there is an exploded illustration in side elevation outline of a mounting lug 1 with holes to receive a source of vibration which is fixed to foreplate 2.

On the reverse of foreplate 2 is mounted location lugs 8 (shown in section) and flexibly bushed lug 9(shown in section).Also is depicted in side elevation a 'quikfit' backplate 5 attachment for mounting to a boom as means of support of the whole assembly. Onto backplate 5 is fixed flexible bushed clevis lugs 10 which are to be assembled to foreplate 2 by locating pin 11 washer 12 and locking split pin 13. The flexible material is shown as 14 with central steel tubes 15. To provide lateral stability and eliminate any pivot action about pin 11 the bushings lugs and pin would be duplicated alongside to provide a minimum of four lug fixings on backing plate 5.

Referring to figure 3 there is illustrated a tractor 40 mounted on which is a bracket 41 which can be swivelled in a horizontal plane. The bracket 41 is provided with pivot 42 which supports an extendible boom 43. Connected to the free end of boom 43 is a device according to the invention 44 which itself is atteched to a unit 45 consisting of the functional part of a hydraulic vibrator. The unit 45 takes its hydraulic and/or pneumatic power from the tractor 40 through supply conduits not shown.

In operation when removing materials from the walls of the hold of a ship, the tractor is driven to face the wall of the hold and the boom is positioned to place the vibrator rod into contact with the coal covered wall. Operation of the rod effects a drumming action on the wall causing the wall to vibrate in unison and it is under this influence that any material such as coal adhering to the wall slumps to the hold floor.

Refferring to figure 4 there is a sectional view in side elevation outline of a mounting lug 1 with holes to recieve a source of vibration which is fixed to foreplate 2. Backplate 5 has similar 'quickfit' attachment for mounting to a boom or support for the whole assembly. A series of cylinders 16 with one end closed with a captive nut 18 in the closed end are stud bolted 19 to and through backplate 5. Internally threaded spacer tubes 15 are also stud bolted 17 to and through foreplate 2. Flexible elastic material 14 is bonded between cylinder 16 and spacer tube 15 to fix backplate 5 to foreplate 2 without metal metal contact.

This arrangement could be considered similar to the device concieved in figure 1 without any flexible material but utilizing only double acting cylinders and pistons balanced by the use of springs or compressed gas.

The choice of the most resilient material for each particular application will be made by the skilled addressee of this specification. Rubber, synthetic rubber, expanded, rubber or plastic and composite materials can be used to advantage. A sandwich form of construction can also be used to provide a variable degree of damping depending on the force applied.

Prior Art Vibration damping equipnent suitable for this application is known from GB 2 241 045 However this relies on an inflatable pneumatic tube, with or without a tyre, or on a tyre alone to provide the necessary cushioning effect. This known arrangement suffers fam several disadvantages. If the tube or tyre should burst then the breaker sags and is no longer controllable.

At worst the breaker will fall out of the tyre. In any event , operations must be suspended immediately to avoid damage to the ship and/or equipnent.

Suspending operations will inevitably disrupt unloading and may cause the ship to miss the tide.

Claims

CLAIMS.

1. A vibration insulation device comprising of flexible resilient material in the form of bushing, a source of vibration and a supporting structure for the source of vibration, said source of vibration and said supporting structure being connected to said flexible bushing in such a way that said flexible bushing damps the transmission of vibrations from said source of vibration to said supporting structure.

2. A vibration insulation device comprising of a solid mass of resiliently flexible material clamped between the said source of vibration and the said supporting structure.

3. A vibration insulation device comprising of a solid mass of laminated resiliently flexible material clamped between the said source of vibration and the said supporting structure.

4. A vibration insulation device comprising of a solid mass of honeycombed resiliently flexible material clamped between the said source of vibration and the said supporting structure.

5. A vibration insulation device comprising of a foam filled tyre or tube clamped between the said source of vibration and the said supporting structure.

6. A vibration insulation device as claimed in claims 1.2.3.4.5.

wherein said means is assisted by springs contained by pistons in cylinders.

7. A vibration insulation device as claimed in claims 1.2.3.4. & 5. wherein said means is assisted by compressed gas contained by pistons in cylinders.

8. A vibration insulation device as claimed in claims 1.2.3.4.

5.6 & 7 wherein said means damps the transmission of vibration to a supporting structure in the form of a boom.

9. A vibration insulation device as claimed in claim 8 wherein the supporting structure is an extendible boom.

10. A vibration insulation device as claimed in claims 8 and 9 wherein the supporting structure is connected to a mobile power source such as a tractor.

11. A vibration insulation device as claimed in claims 8.9. & 10 wherin the supporting structure is a boom adapted to be moveable about an axis.

12. A vibration insulation device as claimed in any of the previous claims wherein the source of vibration is a concrete breaker.

13. A vibration insulation device as claimed in claim 12 wherein the concrete breaker has a chisel or point end.

14. A vibration insulation device as claimed in claims 12 & 13 wherein the concrete breaker has a blunt or hammer type head.

15. A vibration insulation device as claimed in claim 12 wherein the concrete breaker is fitted with a cup into which is fixed a log of wood.

16. A process for removing material adhering to upwardly extending surfaces which comprises imparting vibrations to the surface

17. A process for removing materials adhering to upwardly extending surfaces as claimed in claim 16 wherein the material is coal, urea, chemical salts or ores.

18. A process for demolition of mortar bonded structure such as buildings which comprises imparting vibrations to the structure using the device as claimed in claims 1 to 14.

19. A vibration insulation device substantially as illustrated in the accompanying drawings.