GB2537891A

GB2537891A - Compression device

Info

Publication number: GB2537891A
Application number: GB1507370.3A
Authority: GB
Inventors: Thompson Tim
Original assignee: Jack Sealey Ltd
Current assignee: Jack Sealey Ltd
Priority date: 2015-04-30
Filing date: 2015-04-30
Publication date: 2016-11-02
Anticipated expiration: 2035-04-30
Also published as: GB201507370D0; GB2537891B

Abstract

A compression device 100 adapted for compressing automotive coil springs is disclosed. The compression device comprises upper and lower clamps 22, 24 for engaging with upper and lower parts of the spring to be compressed. The compression device includes force or load sensing means operatively connected to at least one of said clamps and capable of determining the compressive force to which the coil spring is currently being subjected. The sensing means additionally includes an indicator by means of which an operator can establish whether the compressive force has exceeded a threshold value. The indicator means may be visible, audible or haptic. The indicator may be a gauge 60 having a pointer 68 and threshold demarcation. The sensing means may include a digital transducer and data entry, storage and processing means. The compression device may include a hydraulic circuit wherein a hydraulic pressure gauge is the sensing means.

Description

Intellectual Property Office Application No. GII1507370.3 RTM Date:11 November 2015 The following terms are registered trade marks and should be read as such wherever they occur in this document: Perspex (page 11) Intellectual Property Office is an operating name of the Patent Office www.gov.uk/ipo

COMPRESSION DEVICE

Field of the Invention

The present invention relates to a compression device, and more particularly to a compression device adapted for compressing automotive coil springs or other arcuate or otherwise unwieldy structures which are required to be compressed for testing purposes or to facilitate their fitting or insertion in some larger apparatus, or their removal therefrom.

Background of the Invention

Coil springs are in widespread use in many different industries, but they find particular application in the automotive industry in which they are employed most commonly in vehicle suspensions to provide resilience and dampening as between each of the wheels /5 of the vehicle and the chassis thereof.

As can be appreciated, in this particular application, coil springs are subjected to almost continual non-uniform forces throughout the life of the vehicle whenever it is in motion, and as the life of modern vehicles improves, so must the longevity of the coil springs in their chassis. Such improvements, particularly more recently, have resulted in coil springs being manufactured in more durable steels which are intrinsically harder or stiffer than previously, and therefore inherently more resistant to compression forces. Aside from the general trend of providing components with greater longevity, there has been an increase in consumer demand for more robust, all-terrain or so-called sports utility and recreation vehicles (SUV, RV), jeeps and the Like. Not only are these vehicles far heavier than conventional passenger vehicles, but also there is the possibility that they are subjected to far harsher driving conditions, such as off-road driving. Naturally, the coil springs employed in the suspensions of such vehicles are required to be much more robust.

As a direct result of their increased durability, resilience and stiffness, it is becoming increasingly difficult to safely insert, replace, maintain, repair and test coil springs. Additionally, their shape makes them very unwieldy and thus difficult, mechanically, to grip and thereafter apply a (usually compressive) load.

Common workshop coil spring compression devices are mostly manually operated and are often in the form of a floor-standing rig or hand-held clamp. Such devices typically employ the simple mechanical advantage principles of a lever of some form, and a ratchet or other retaining mechanism. In compressive use, a coil spring is inserted between a pair of separated broadly identical clamps having generally semi-, partially or completely annular (i.e. like a yoke) cross-sections from the edges of which depend correspondingly shaped skirts which together define a generally semi-, partially or completely annular groove or channel. Prior to commencing compression of the spring, it may be tethered to the rig or device, and a drop-down guard, shield or visor may be Lowered around the spring and the clamps which hold it. Once secured in place, the Lever mechanism is worked repeatedly to progressively increase the compressive load on the spring.

is By using clamps of incomplete annular cross-section, coil springs of a range of different diameters (and thus radii of curvatures) can be disposed in the clamps. By contrast, where the clamps are completely annular, only coil springs having external and internal diameters of their final windings less than the inner dimension of the outer skirt and the outer dimension of the inner skirt respectively can be accommodated in the clamps, and of course the coil spring can only be clamped at its end coils, whereas partially or semi-annular clamps allow for clamping sections of coils between the end coils. In any event, the partially or completely annular clamps are designed both to provide as much purchase as possible on the correspondingly shaped arcuate and cylindrical section of the coil spring received therein, and also to provide, as far as is possible, some means of retaining that section within the clamp and thus the compression device when under compression.

There are two problems, Largely related, which require further explanation here. Firstly, although most coil springs are nothing more than helically or spirally wound wires, it is intrinsically mechanically difficult to obtain secure purchase on such structures. The optimum purchase which can be obtained on a wire of circular cross-section would be provided by a clamp having a groove or channel of exactly corresponding shape and dimensions. In theory this may be possible, but it is highly impractical. In practically all cases therefore, the clamps are not a snug fit around the section of wire of the coil spring they receive, and the contact between the clamp and the relevant section of the coil spring is predominantly tangential and frictional. The second issue, directly related to the first, is that the tangential/frictional purchase is prone to slip. This is not only problematical, but also, in certain circumstances, extremely dangerous, because coil springs can become unstable when under compression if the compressive force applied at the either end not exactly coaxial with the spring. This instability under load results initially in a portion of the coil spring bulging outwardly at its waist (and a corresponding diametrically opposed portion contracting), which in turn leads (almost immediately) to the spring slidingly escaping entirely, unpredictably, and very rapidly, from the device within which it is being compressed, and immediately then expanding to its uncompressed size. Although the skirts provided on the clamps described above do provide some restraint, they have proved insufficient on a number of occasions, and indeed there have been many reports of workshop personnel being injured by flying coil springs.

When it is considered that the typical compressive forces which are required to compress modern automotive coil springs ranges from 1-5 tonnes, and the weight of such springs can range 0.5kg to 4kg, the dangers can be readily appreciated.

In addition to the inherent problems and dangers associated with coil spring compression, there is additionally a tendency for workshop personnel to over-compress the coil spring in whatever compression device they may have to hand. This serves only to exacerbate the problems described above. Indeed, it has been suggested that the primary cause of workshop injuries involving coil springs results almost exclusively from their over-compression.

Accordingly, it is an object of this invention to provide a compression device which obviates the abovementioned disadvantages to at least some extent, if not completely, and fundamentally increases the safety of coil spring compression.

Summary of the Invention

According to the present invention, there is provided a compression device adapted for compressing a spring component having a coil structure which encircles an axis of said component, and said device comprising an upper and lower clamp between which at Least some axial portion of said spring component may be disposed and which provide at Least some purchase on upper and lower arcuate sections of said coil structure, one or both of said clamps being capable of being caused to translate in a direction axially parallel with that of the spring component and in a controlled and mechanically advantageous manner so as to exert a progressively increasing compressive load on said spring component, characterised in that said compression device includes sensing means operatively connected to at least one of said clamps and capable of determining the compressive force to which said spring component is currently being subjected, said sensing means additionally including an indicator by means of which an operator can establish whether the compressive force has exceeded a threshold value.

Preferably the indicator is one or more of visible, audible or haptic, most preferably visible. Yet further preferably, said indicator takes the form of a gauge having pointer means which is coupled to said sensing means and is caused to move as the compressive force being exerted by said clamps increases, said gauge further including a threshold demarcation at some point along the sweep of said pointer means, said demarcation being such that an operator can visibly establish the position of the pointer means in relation thereto, and therefore whether the compressive force has exceeded the threshold value indicated thereby.

Most preferably the gauge includes a dial, and the pointer means is needle which moves rotationally above the dial, and preferably the threshold demarcation is one of (i) A point, line or band provided on the dial, (ii) The end of any in (i), (iii)The intersection of any (i) with another entity of the same or different type, (iv) A colour change in any of (i)-(iii) above; And is provided on said dial otherwise in close proximity to said needle and at some point along the rotary sweep made thereby.

In a preferred embodiment, where the indicator means is visible, the threshold demarcation may be any one of: - Colour (e.g. change from green to red), - Size (e.g. - Shape - The appearance, disappearance or change in anything visible on or in said visible indicator means, being one or more of the above or not.

Most preferably, the compression device is a floor-standing compression rig, and the gauge is one or more of removably, releasably and rotateably secured at the top thereof. Further preferably said gauge is provided in a housing similarly secured to said rig, said housing preferably being provided with a planar translucent face, inclined upwardly as between a front and a rear edge so as to define a front and rear of said housing, such additionally serving to protect the gauge underneath it.

In an alternative preferred embodiment, the compression device is a portable and/or hand-held compression device.

is Preferably, where the compression device is a floor-standing compression rig, the threshold level of exerted compressive force is in the range 1-5 tonnes, most preferably in the range 1-3 tonnes, and ideally approximately 1.5 tonnes, and where the compression device is portable and/or hand-held, the threshold level of exerted compressive force is in the range 0.8-1.5 tonnes, ideally approximately 1 tonne.

Preferably the indicator means is one of analogue or digital. In the latter case, the sensing means preferably includes a transducer.

Most preferably, the compression device includes a hydraulic ram circuit connected to at least one of the clamps and by means of which said clamp is caused to translate relative to the other, and by means of which a compressive force may be brought to bear on a coil spring component disposed therebetween. Most preferably, said sensing means is operatively coupled to said hydraulic ram circuit by means of a hydraulic capillary connected. In a most preferred embodiment, said sensing means takes the form of a hydraulic pressure gauge.

In an alternative embodiment where the indicator means is digital, the sensing means includes transducer means for converting a force or pressure measurement into an electrical signal representative thereof, and said indicator means is operatively electrically connected to said sensing means.

In the case where the indicator means is audible, it consists of an audible alarm which is activated at a threshold level of exerted compressive force.

Preferably, one or more of said compression device, said sensing means and said indicator means is provided with electrical connection means to allow for the connection of external computing means thereto.

In a most preferred embodiment, said sensing means further includes data entry means, data storage means, and data processing means such that data specific to the spring component about to be compressed can be provided, said data storage means and said data processing means then cooperating to process said specific data so as to adjust the is threshold value of compressive force to which said spring component may be subjected in said compression device.

In a preferred embodiment, the compression device is electrically connected to computing means, which provides said data entry, data storage and data processing functionality. Alternatively, one or more of said data entry, data storage and data processing means are provided integrally within and as part of said compression device.

In either case, where the indicator means is visible, the threshold demarcation is preferably adjusted according to the entered data specific to the spring component about to be compressed. In the case of analogue indicator means, this may be as simple as slightly rotating the dial slightly so that the needle needs to travel rotationally to a greater or lesser degree before passing the threshold demarcation. In the case of a digital indicator means which might provide a display of the compressive force to which the spring component was at that time being subjected, such display might turn red when the threshold value, adjusted according to the specific data provided for said spring component, had been exceeded.

In an alternative embodiment, said compression device is a hand-held compression device adapted for compressing smaller spring components provided with a pair of clamps, one being at one end of the device and another being screwingly mounted relative thereto, relative displacement thereof being effected by rotating the screw which causes translation of one clamp relative to the other in mechanically advantageous manner, and thus bringing a compressive force to bear on a spring component disposed therebetween.

In a yet further preferred arrangement, the compression device includes secondary sensing means which provides data specific to the spring component currently disposed between the clamps of said compression device (including is current compressed length), said data being provided to said data processing means which automatically adjusts the threshold value of compressive force to which said spring component may be subjected.

Although the provision of secondary sensing means is a preferred embodiment, it is contemplated by the inventor that it may not be necessary, and that threshold value adjustment, depending on the specific physical qualities of the spring component currently under compression within the device might automatically be achieved by virtue of Hooke's Law, which states that for springs: F = -kx Where F is compressive or tensile Force, k is the spring constant for the spring under elastic compression, and x is the extension or contraction which will occur as a result of the force applied.

For instance, for one stroke of the mechanically advantageous level mechanism of the compression device, the clamps will move toward one another always by the same amount; however, if the spring is weak or lacking resilience (i.e. "k" above is small), then the compressive force applied as a result of this displacement will be also low, and the ratio "F/k" will have a certain value, for all further elastic contractions of the spring.

Conversely, if the spring is stiff or of Large resilience (i.e. "k" above is large), then the compressive force applied as a result of this (fixed) displacement will be high -a single stroke will take much more effort. However, the ratio "F/k"will again have a certain value, for all further elastic contractions of the spring. The only other factor which can have a bearing here is the Length of the spring which, in a particularly preferred aspect of the invention is determined prior to or during compression of the spring component, and used in the automatically adjustment the threshold value, especially in the case where the compression device is in electrical communication with, or is integrally provided with, data storage and data processing means.

By providing a compression device for coil springs with a visible or audible indicator (e.g. an audible alarm), operators are made immediately aware that the level of compressive force they have applied to a coil spring at that time within the device has exceeded a threshold level, and furthermore that they are now applying a compressive force which might be considered as dangerous, at least as far as the possibility of coil spring instability, and thus escape from the device, might be concerned. This is a vast improvement on current workshop practices, where coil springs are often compressed to purely arbitrary Levels without any notion of danger even having been contemplated. It is such incautious and careless practices the invention overcomes.

A specific embodiment of the invention, provided by way of example only, will now be described with reference to the accompanying Figures wherein:

Brief Description of the Figures.

Figure 1 shows a perspective view from one side of a coil spring compression device according to the present invention, Figure 2 shows a perspective view of the compression device of Figure 1 from the opposite side, Figure 3 shows a perspective view of the top-mounted dial provided in the compression device of Figure 1, Figure 4 shows a perspective view of a hand-held coil spring compression device according to the present invention, and Figure 5 shows an enlarged view of the dial of the device depicted in Figure 4.

Detailed Description

Referring firstly to Figure 1, there is shown a coil spring compression device indicated generally at 2 which is in the form of a floor-standing rig supported on a base indicated generally at 4 consisting of a pair of elongate feet 6, 8 securely bolted on either side of a central platform 10 from which perpendicularly upwardly extends a column 12 which is also securely fixed, for example by welding, to the platform 10. Column 12 may be of any suitable cross-sectional shape, although in most cases it will be circular, square or rectangular in cross-section, and as said structure is load bearing, it is designed to be sufficiently substantial to easily withstand the loads to which it will be subjected in use.

The column 12 additionally provides a guide for a pair of correspondingly shaped sleeves 14, 16 to which are welded bosses 18, 20 which provide mounts for clamps indicated generally at 22, 24 respectively. The sleeves 14, 16 are capable of translating up and is down the column coaxialty therewith, but in the case of sleeve 14, it is fixed in place at a desired location along the length of said column, and at a desired distance from the lower sleeve 16 by means of a pair of cotter pins 14A, 14B, which pass through suitably sized axially aligned holes in either side of the sleeve 14, and additionally through one of a plurality of corresponding sized holes drilled through said column 12 at various distances along the length thereof and at suitable spacings so that when the sleeve 14 is slid up or down the column, the pair of holes drilled through the sleeve aligns exactly with a corresponding pair of holes drilled through the column allowing for insertion of the cotter pins 14A, 14B. Said cotter pins are ideally prevented from working free after insertion by means of circlips or the like (not shown) applied to their proud-standing free ends disposed to the outside of the sleeve 14. Cotter pins 14A, 14B may additionally provide the means whereby one end of each of a pair of tethering chains 14X, 14Y may be fixed.

At the uppermost end of the column 12 is provided a housing 40 which is rotateably and/or removably mounted on the column 12. In one embodiment, the column is formed by bending steel sheet of sufficient thickness into a square or rectangular cross-sectional shape so that the column structure is hollow, and the housing 40 is provided with a correspondingly shaped lug or skirt which can be received snugly within the hollow cross-section the column, and thus be removably mounted therein.

As can be seen from the Figure, the clamps 22, 24 are substantially identical but are disposed in opposing relation. Each clamp is of generally semi-or partially annular cross-section, with the free ends of this cross-section extending arcuately away from the bosses 18, 20 on which the clamps are mounted. Depending (or in the case of clamp 24, upstanding) from the arcuate edges of the semi-or partially annular elements of said clamps are correspondingly shaped skirts 22A, 22B which together define a generally semi-or partially annular channel, more clearly seen for clamp 24 at 24C. It is within these channels that arcuate sections of a coil spring (not shown) to be compressed in the device 2 are received, possibly (but not necessarily) being arcuate sections in their top and bottom coils. Once seated in a generally upright condition between the clamps, the tethering chains 14X, 14Y may be attached around or to particular sections of said coil spring, possibly by means of karabiners [not shown] provided at the free ends thereof.

is Referring now to Figure 2, the opposite side of the device 2 from that depicted in Figure 1 can be seen. Of particular note is the mounting of sleeve 16 to a hydraulic strut indicated generally at 42, or more precisely to the free end of the piston rod 44 which emerges from the hydraulic cylinder 46 thereof. Hydraulic pressure within the cylinder 46 is progressively increased by means of a foot pedal 48 attached to a lever 50 which ratchets up the fluid pressure within the cylinder in known fashion. A release pedal and Lever 52, 54 respectively provides a means of releasing the hydraulic pressure in a gradual and controlled manner.

As mentioned above, once a coil spring to be compressed is correctly seated on the lower clamp 24 and the upper sleeve 14 has been suitably positioned and secured in place such that the upper clamp 22 loosely retains an upper portion of the coil spring, an operator then repeatedly works the foot pedal/lever 48/50 as shown at arrow 51 which in turn, by means of the hydraulic strut 42, mechanically advantageously causes displacement of the lower sleeve 16 towards the (fixed) upper sleeve 14, as shown by arrow 17, and therefore with the coil spring seated between these clamps acting to resist this displacement, the compressive force exerted thereon increases.

The skilled person will note from the description thus far provided, an operator can continue to work the pedal/level 48/50 repeatedly without any warning or failsafe condition preventing further compressive load being applied to the coil spring. Even despite the provision of tethering chains (which regrettably are not always deployed), the facility for considerable and often extreme over-compression is an inherent flaw in these types of devices.

Accordingly, within the column 12 is provided a hydraulic capillary in fluid communication with the compression fluid within the cylinder 46, and the housing 40, or more specifically, a pressure gauge provided within said housing, and as depicted in Figure 3. In this figure, the housing 40 is shown rotateabLy mounted to the uppermost free end of column 12, and within said housing is provided a pressure gauge indicated generally at 60 disposed behind a translucent or transparent glass or Perspex® cover 62 secured to the housing at its corners with screws as shown at 64A 64B, 64C, 64D.

Gauge 60 includes a circular dial 66 in the middle of which a needle 68 is rotationally is mounted at 70 which in use, and as a result of increasing compressive force applied to the coil spring seated at the time between the clamps 22, 24 rotationally sweeps in a clockwise manner above the dial 66. Printed or otherwise marked on the dial is an indicator band 72. Numerals 74, 76 may also be provided on the dial adjacent the indicator band at appropriate positions to denote a particular magnitude of compressive force currently be applied between the clamps in an appropriate unit, e.g. Newtons, Tonnes, or perhaps a the numerals may be indicative of an applied pressure. Said indicator band is ideally printed in two colours, preferably green and red, and disposed on the dial 66 relative to the needle 68 such that a starting edge 78 of the green portion of the band lies substantially underneath the needle when the device is not applying any compressive force. The edge 80 of the green portion indicator band remote from the starting edge 78 is disposed in the exact place where it is determined, either a priori or by the device (and/or optionally computing means in electrical communication with the device) itself in real time, that the safe threshold for applied compressive force should be set. From this point 80 onwards to the end edge 82, the indicator band, is printed in a red colour, such that it is immediately evident to an operator of the device as the applied compressive force increases, and therefore the rotary displacement of the needle increases from its resting or zero force applied disposition, that the needle as moved from a position above the green portion of the indicator band to a position above a red portion of the indicator band, the latter signifying that the applied compressive force has exceeded the safe threshold level.

Referring now to Figure 4 (in which Like numerals already used in Figures 1-3 are employed where appropriate to reference similar parts), there is shown a hand-held compressive device indicated generally at 100 which includes clamps 22, 24 of identical shape but mounted on the device in opposing relation so as to be capable of each receiving in their partially or semi-annular grooves 22C, 24C arcuate upper and lower portions of a coil spring (not shown).

Clamp 24 in the Figure 4 is directly screwingly and fixedly mounted to a sliding shaft 102 which can be caused to be displaced towards clamp 22 by means of screw wheel 104 which engages it, either directly or indirectly. The end of the shaft 102 remote from clamp 24 is concealed within the body 106 of the device, such being elongate and is capable of receiving a significant portion of the said shaft as it moves inwardly of the device. In this arrangement, clamp 24 is displaced, and clamp 22 is again fixedly and screwingly mounted directly to the body 106 by means of a thread portion 108 (See Fig. 5) in which the body 106 terminates, but of course the alternative arrangement where clamp 22 is caused to displace towards a fixed clamp 24 is equally possible.

As for the compression device of Figures 1-3, device 100 is provided with a gauge indicated generally at 60 and in operative communication with a pressure or load applying surface, component or fluid, within or forming part of the device 100. In the device of Figures 5 and 6, such operative communication is provided through a valve, port, channel or capillary indicated generally at 110 and seen in greater detail in Figure 6. In the case where device 100 is hydraulic, 110 represents a hydraulic capillary communication with the hydraulic cylinder which the body 106 essentially contains. A release valve 112 is provided which allows the gradual and safe release of the hydraulic pressure built up within the device as a result of continual winding of screw 104 in the appropriate or "tightening" direction. As such winding occurs, the hydraulic capillary effectively communicates the current pressure to the gauge 60, which is broadly identical to that of the device 2 and as described in detail with reference to Figure 3.

Claims

CLAIMS1. A compression device adapted for compressing a spring component having a coil structure which encircles an axis of said component, and said device comprising an upper and lower clamp between which at least some axial portion of said spring component may be disposed and which provide at least some purchase on upper and lower arcuate sections of said coil structure, one or both of said clamps being capable of being caused to translate in a direction axially parallel with that of the spring component and in a controlled and mechanically advantageous manner so as to exert a progressively io increasing compressive load on said spring component, characterised in that said compression device includes sensing means operatively connected to at least one of said clamps and capable of determining the compressive force to which said spring component is currently being subjected, said sensing means additionally including an indicator by means of which an operator can establish whether the compressive force is has exceeded a threshold value.
2. A compression device according to claim 1 wherein the indicator is one or more of visible, audible or haptic.zo
3. A compression device according to claim 1 wherein said indicator takes the form of a gauge having pointer means which is coupled to said sensing means and is caused to move as the compressive force being exerted by said clamps increases, said gauge further including a threshold demarcation at some point along the sweep of said pointer means, said demarcation being such that an operator can visibly establish the position of the pointer means in relation thereto, and therefore whether the compressive force has exceeded the threshold value indicated thereby.
4. A compression device according to claim 3 wherein the gauge includes a dial, and the pointer means is needle which moves rotationally above the dial.
5. A compression device according to claim 3 or 4 wherein the threshold demarcation is one of (i) A point, line or band or a shape of any kind, (ii) The end of any in (i), (iii)The intersection of any (i) with another entity of the same or different type, (iv) A colour, or a change in colour of any of (0-Cu) above, (v) The appearance, disappearance or change in any of (i)-(iv) above.
6. A compression device according to claim 5 when dependent on claim 4 wherein the threshold demarcation is provided on said dial in close proximity to said needle and at some point along the rotary sweep made thereby.
7. A compression device according to any preceding claim wherein the compression device is a floor-standing compression rig, and the gauge is one or more of removably, releasably and rotateably secured at the top thereof.
8. A compression device according to any of claims 1-6 wherein the compression device is manually portable and hand-held.
9. A compression device according to any preceding claim wherein the indicator means is one of analogue or digital.
10. A compression device according to claim 9 wherein the indicator means is digital, and the sensing means includes a transducer which provides an electrical signal representative of the compressive force currently being applied by the device to said digital indicator means.
11. A compression device according to any preceding claim wherein the compression device includes a hydraulic ram circuit connected to at Least one of the clamps and by means of which said clamp is caused to translate relative to the other, and by means of which a compressive force may be brought to bear on a coil spring component disposed therebetween.
12. A compression device according to claim 11 wherein said sensing means is operatively coupled to said hydraulic ram circuit by means of a hydraulic capillary.
13. A compression device according to any of claims 11-12 wherein said sensing means takes the form of a hydraulic pressure gauge.
14. A compression device according to any preceding claim wherein the indicator means is audible, and consists of an audible alarm activated when a threshold level of exerted compressive force is one of met or exceeded.
15. A compression device according to any preceding claim wherein one or more of said compression device, said sensing means and said indicator means is provided with electrical connection means to allow for the connection of external computing means thereto.
16. A compression device according to any preceding claim wherein said sensing means further includes data entry means, data storage means, and data processing means such that data specific to the spring component about to be, or currently being, compressed can be provided, said data storage means and said data processing means is then cooperating to process said specific data so as to adjust the threshold value of compressive force to which said spring component may be subjected in said compression device.
17. A compression device according to claim 16 wherein the compression device is electrically connected to computing means, which provides data entry, data storage and data processing functionality.
18. A compression device according to any of claims 15 wherein one or more of said data entry, data storage and data processing means are provided integrally within and as part of said compression device.
19. A compression device according to either of claims 17 or 18 wherein the indicator means is visible, and the threshold demarcation is adjusted according to the entered data specific to the spring component about to be compressed.
20. A compression device according to claim 9 and any claim dependent thereon wherein the indicator means is analogue, and the threshold demarcation is adjusted mechanically according to the entered data specific to the spring component about to be compressed.
21. A compression device according to claim 2 or any claim dependent thereon wherein the indicator means is visible and consists of one of a VDU, a digital display, and LED or LCD display.
22. A compression device according to claim 21 wherein the indicator means provides a display of the compressive force currently applied by said device, such display being caused to display such value in a different colour when said threshold value is either met or exceeded.
23. A compression device according to claim 16 and any claim dependent thereon wherein the data entry means comprises secondary sensing means which provides data specific to the spring component currently seated within said compression device, said data being provided to said data processing means which automatically adjusts the is threshold value of compressive force to which said spring component may be subjected.