AU618019B2 - Improvements in and relating to dynamometers - Google Patents

Description

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AUSTRALIA

PATENTS ACT 1952 COMPLETE SPECIFICATION Form

(ORIGINA.)

FOR OFFICE USE Short Title: Int. Cl: Application Number: Lodged: Is1 68 01 Complete Specification-Lodged: Accepted: Lapsed: Published: Priority: Related Art! TO BE COMPLETED BY APPLICANT A iAI..

Name of Applicant: Mark Patrick GALVIN Address of Applicant: -&9-eA-S'D-RG-A-D

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fl9 cM-t~rc~\ Actual Inventor: Address for Service: GRIFFITH HACK CO., 601 St. Kilda Road, Melbourne, Victoria 3004, Australia, Complete Specification for the invention entitled: IMP'ROVEMENTS IN AND RELATING TO DYNAMOMETERS The following statement is a full description of this invention including the best method of performing it known to me:-

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This invention relates to dynamometers and more particularly relates to the mounting and engagement of such instruments with a driven rotatable wheel, wheel mounting, or shaft for the accurate measurement of output torque or turning movement at such point.

The invention is particularly applicable to, but not necessarily confined to, the measurement of driving wheel torque for motor vehicles in measuring and comparing the power characteristics of the engine of the vehicle whilst installed in the normal operable position in the vehicle, such as whilst in the process of tuning the vehicle engine for maximum efficiency and/or desired effectiveness and power output in operation.

In some cases of conventional dynamometer measuring of power output the vehicle engine may require to be removed for direct coupling to the engine cr gearbox drive shaft, or other parts of the vehicle may be removed to gain access to the drive shaft; but this method is labour intensive and does not provide true readings for the drive wheel(s) output. Other conventional equipment and methods of measuring drive wheel or shaft power output or torque involve expensive roller or chassis dynamometer apparatus; and in the case of the roller type dynamometer apparatus these are usually very large and occupy a large work space; and additionally, with their operation involving rolling contact with the driving wheels tyres, are subject to measurement errors due to loss of up to 25% (dependent on loading) wheel power at the tyre/roller interface, speed of operation restriction (there being danger of tyre blow-out with prolonged high speed testing), and difficulties with secure mounting of front wheel drive veh$,cles.

An object of the present invention is to provide a relat- -2i ively inexpensive and compact dynamometer and mounting apparatus which overcomes the aforementioned disadvantages of conventional equipment and measuring methods and provides for ready fitment directly to a wheel or hub of a vehicle, or to such as the power take-off shaft of a tractor or the like, with a minimum of effort and labour skills. Other and more particular objects and advantages of the invention will become apparent from the ensuing description.

According to a first aspect of this invention therefore, there is provided a dynamometer and mounting apparatus comprising a base support mounting at its upper part a S bearing assembly arranged to detachably and rotatably 0 mount a coupling for rotation of said coupling about a 0 S substantially horizontal axis,said coupling having one 1 outer end provided with or arranged to receive a part arranged for rigid connection to a drive wheel,wheel hub or a driven shaft outer end part for axial alignment and direct rotation therewith,and said coupling having an opposite end part arranged for detachable axial sliding connection to the input drive shaft of a power absorbing assembly mounted on and supported by the base support; there being means for measuring the speed of rotation of the coupling and input drive shafts and for measuring and/or computing the power absorbtion of said power absorbing assembly during operation, and to determine the equivalent braking torque of the connected driven wheel or hub or driven shaft for display on an associated and connected information receiving and display means.

-3- Typically for a vehicle having linked opposite side drive wheels (front or rear) the apparatus of the preceding paragraph will be duplicated for each drive wheel and employ a common receiving and display means which can display separately the torque applicable to each drive wheel; or by the provision of a common connection or such as a hydraulic coupling between the separati power absorbing assemblies can be arranged to synchronise the speed of rotation of both drive wheels and display the average torque and common speed of rotation (Power speed x torque).

Some preferred aspects of the invention will now be described by way of example and with reference to the accompanying drawings, in which figures 1-3 and 5 relate to a first form of the apparatus and figures 8-11 relate to a second form, with figures 4,6 and 7 relating to components applicable to both forms. More particularly: FIGURE 1 is a diagrammatic end view illustrating apparatus Sin accordance with the invention applied to the two opposite side driving wheel hub mountings of a typical motor car, FIGURE 2 is a face view (on a larger scale) of the apparatus at one side of the vehicle, as viewed in the direction S of arrows II-II of figure 1, FIGURE 3 is a sectional view in the direction of arrows Ill-III of figure 2, and includes a diagrammatic illustration of associated components, FIGURE, 4 is a view in the direction of arrows IV-IV of figure 3 illustrating a first adaptor plate for use in accommodating a range of wheel stud positions for different vehicles, -4- 0.

I FIGURE 5 is an enlarged exploded side and sectioned view of the coupling and coupling shaft of figure 2, and the first adaptor plate of figure FIGURE 6 is a view (similar to the view of figure 4) of a second alternative adaptor plate for use in accommodating a range of wheel stud positions for different vehicles, FIGURE 7 is a sectional view on line VII-VII of figure 6, FIGURE 8 is a diagrammatic end view similar to figure 1 but illustrating another form of the apparatus applied to the opposite side driving wheel hub mountings of a motor car, FIGURE 9 is a face view similar to figure 2 but of the apparatus of figure 8, as viewed in the direction of arrows

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4 FIGURE 10 is a view similar to figure 3 but of the apparatus of figures 8 and 9, and as viewed in the direction of arrow X-X of figure 9, and FIGURE 11 is a longitudinal sectional view similar to figure 5 but of the alternative coupling arrangement in the apparatus of figure 9.

Referring firstly to figures 1,2 and 3 of the drawings, in applying the invention to a typical motor vehicle 1 with opposite side driven ground wheels 2, generally the simplest and most economically provided connections and mounting will be to the wheel hub parts 3 by means of the usually provided wheel studs 4 and nuts 5 The apparatus may therefor be provided with a standard rigid coupling 6 which may be designed with wheel stud receiving apertures for one or more particular range of vehicle wheel stud spacings and/or be arranged to have fitted thereto an adaptor plate 7 such as that shown in figure 4 with fixed position wheel stud receiving apertures 8. In most cases, wheel studs are relatively short and thus the vehicle drive wheels 2 are simply removed on jacking up the vehicle, and the apparatus positioned at each side *of the vehicle 1 for direct fixing of the standard coupling 6 and/or adaptor plate 7 to the respective wheel hub parts 3.

Other wheel mounting or hub adaptor connection means can be employed and it is envisaged for example that clamp or like engagement or connection means (not shown) can be mounted on the standard coupling 6 and arranged to be engaged with the respective vehicle wheel, wheel hub or rim, or the wheel tyre for dynamometer operation and measuring without removal of 1 the wheels. An alternative hub part mounting adaptor plate 9 is illustrated by way of example in figures 6 and 7 and provides for variable positioning of wheel stud mounting pieces or washers 10 which are radially slidable in slot parts 11 of the plate 9 the adaptor plate 9 being additionally provided with plain bolt apertures 12 for connection to the standard coupling 6. This adaptor plate 9 and the previoutsly mentioned adaptor plate 7 and coupling 6 are shown to be applicable to four stud wheel mountings, and it will be appreciated that other adaptor plates and couplings 6 can be provided for wheels with a different number of studs.

The standard coupling 6 (or any alternative wheel hub or shaft coupling) is provided on one projecting end part of a coupling shaft 13 arranged for rotation about a substantially -6horizontal axis in a roller bearing 14 within an upper support part 15 of a strong base support,generally indicated by the arrow 16,which provides stable ground or floor support for the apparatus and vehicle 1 to which it is connected and transmits dynamometer torque reaction to the ground or floor. The apparatus can be provided with a suitable carrying handle 16a and in the illustrated form the base support 16 has feet parts 16b and these can be made adjustable for height to accommodate floor surface variations for stability.

As an alternative or in addition to the feet parts 16b, the base support 16 can be provided on its underside with at least one roller or castor to facilitate moving and manoeuvring S of the apparatus prior or subsequent to fitment to a vehicle.

It is essential that the apparatus is stable and not movable 99 SI" as a whole when fitted to and supporting the vehicle 1;and thus the roller(s) or castor(s) are preferably mounted or housed in association with a downward spring bias of sufficient strength to normally support the apparatus in a manner allowing 9* projection below the base support 16 of the roller(s) or cas- *2 tor(s) for rolling ground or floor engagement,but on fitment of the apparatus to the vehicle 1 and lowering of the vehicle lifting jack or hoist means employed, the full vehicle weight S• will be transferred to the apparatus overcoming the downward spring bias of the supporting roller(s) or castor(s) and allowing the base support(s) 16 of the apparatus to settle securely on the ground or floor and unable to be movable thereover.

-7i r '1 I 'i The upper support part 15 also mounts a power absorbing assembly which can conveniently be a hydraulic pump assembly, generally indicated by the arrow 17 at the side of the apparatus remote from the vehicle 1 and coupling 6 and having its input drive shaft 18 coupled axially in alignment with the coupling shaft 13 by any suitable shaft coupling 19. Preferably the upper support part 15 is pivotally mounted relative to the base support part 16 for pivoting movement about a transverse horizontal axis 20 to accommodate wheel camber of the vehicle and to facilitate fitment to the respective wheel hub parts 3, or alternatively the base support 16 as a whole can be arr- *go* anged for angular adjustment.

One important feature of the invention resides in the 0 provision of a coupling arrangement which permits fast and simple, but secure direct rigid connection to a wheel hub eg as mentioned by direct securement of the standard coupling 6 and/or an adaptor plate 7 (or the alternative adaptor 9),

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before coupling the hydraulic pump assembly 17 and base support 16 (thus enabling an operator to have easy access and be able to employ a power operated wheel nut removing and fitment tool); and subsequent fast and simple, and again secure, coupling to (and subsequent disengagement from) the hydraulic pump assembly 17 and base support 16 without the need for any tools.

Accordingly, in one preferred aspect of the invention the standard coupling 6 is fixedysecured at the uter end of the coupling shaft 13 and the shaft 13 is arranged to have its medial bearing part slidably axially into and out of engagement with the support bearing 14p and to have its inner opposite end part 13a slidably engagable co-axially with the connection -8- Ir -u -Iruri~C':,rl-r(.-nw.lrnr~l il:i.; rr :I li r- i -1,1.

19 on the pump input drive shaft 18 and in a manner locking the coupling and input shafts 13 and 18 for axial rotation together,eg the coupling shaft inner end part 13a can be provided with external longitudinal keying recesses and splines slidably engagable with complementary internal longitudinal recesses and splines in the connection 19 alternatively the coupling shaft end 13a and mating inner part of the connection may have a square, hexagonal on other regular cross section for similar interlocking effect. In another variation of the invention, it is envisaged that the coupling shaft 13 itself can be substantially permanently mounted for rotation within the bearing 14,eg a press friction fit within the bearing inner annulus or race part for rotation relative to the bearing outer race part, and the standard coupling 6 be arranged S to have its inner end part (or a connection thereof) slidably engagable with and detachable from the outer end of the coupling shaft 13; eg again with such as a slidable keying spline, square, hexagonal or other regular cross section, interlocking connection.

The hydraulic pump assembly 17 for each side of the vehicle 1 may be coupled by hydraulic conduits 21 to a common hydraulic fluid supply tank 22, and preferably (in the case of oil as the working fluid) the contained hydraulic fluid 23 is maintained cool and stable under operating conditions by the provision of a suitable heat exchanger 24. The heat exchanger may simply comprise a conduit tchrough which cool water is passed. In the case of the working hydraulic fluid being a constant supply of cool water, the supply tank 22 and heat exchanger 24 can be dispensed with.

-9i i i i i i I- _lijiiii- _i The hydraulic pump assemblies 17 are each provided with a pressure reduction control valve 25 either mounted thereon as shown and arranged to be controlled and adjusted manually or remotely by way of electronic, pneumatic or hydraulic means a servo controlled pressure reducing valve .25 can be employed), or the control valve 25 can be mounted some distance away from the respective pump assembly 17 at a convenient position for manual or other control and adjustment. The control valve 25 controls the braking torque by restricting the pump output, and measurement of the torque can be by measurement of the pump pressure in the hydraulic circuit before the control valve 25, or by alternatively mounting the pump assembly 17 on a trunnion or other movable mounting and measuring the torque C 9 reaction of the pump assembly 17 with such as, a strain gauge, spring balance or other suitable force measuring instrument 0 or device.

0.0. In addition to torque measurement, dynamometer rotation speeds must be measured and th.s can be done by means of such as an electronic or mechanical tachometer or like speed trans-

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ducer 26 positioned at the shaft coupling 19 and arranged to transmit an electronic sagnal by appropriate connections 26a to an electronic signal receiver and display panel 27. Connections 1!7a from the pump assemblies 17 for transmission of the pump pressure signal and 25a to a servo control for valve can extend to the receiver and display pandl 27, and such receiver and display panel 27 may display the speed at N and torque at P, and be provided with a speed selection control at N' and a torque selection control at With the addition of electronic or mechanical feed back circuits the dynamometer apparatus can be run in two automatic modes, namely a. at constant speed irrespective of .input torque, and b. at constant torque irrespective of input speed, The aforegoing and illustrated apparatus provides for linking of the hydraulic fluid supply between the two hydraulic pump assemblies 17 and an averaging of the torque output measurement between the two driving wheels or hub parts of a vehicle; but it will be appreciated that the common fluid supply source 22,23 need not necessarily be employed and that the respective pump assemblies 17 can be self contained assemblies having their own incorporated or connected fluid supply sources, and provision can be made for either individual wheel torque measurement and/or averaged wheel torque measurement by the employment of appropriate hydraulic coupling and/or mechanical or electronic linking, With the typical two opposed driving wheels and hydraulically and/or electronically linked apparatus, 1 t« the control valves 25 can be regulated for synchronised rotat- ,i0 ional speed of the respective wheel hub parts 3 and automatically adjustable individually to vary output pressures in the Srespective apparatus hydraulic systems as may be necessary S to offset load variation eg such as may occur with brake lining drag and/or bearing/transmission friction power losses, whilst maintaining constantly synchronised rotational speeds.

Referring now to figures 8 to 11 of the accompanying drawings, in another fout of the invention, two similar units are applied as before and located one each side of the motor vehicle I to be tested; and each apparatus includes a standard rigid coupling 6 which mia be arranged either for direct fit- -11- I I I ment to the respective side wheel hub part 3 or by way c the adaptor plate 7 of figure 4 or alternative adaptor plate assembly 9 of figures 6 and 7. Again alternative adaptor plate, clamp or other connection means can be employed to enable simple and fast fitment to (and subsequent detachment from) the wheel hub part 3 or wheel assembly 2 before engagement of the coupling to the main body and components of the apparatus. In this arrangement the standard coupling 6 is fixedly secured to or formed integrally at one end of a main *o support shaft 13', and such shaft 13' is arranged to be slidably located through a roller bearing 14' mounted in an upper mounting part 28 mounted on an upstand 29a extending from a substantially horizontal base part 29b of a strong base support (generally indicated by the arrow 29).

The upper mounting part 28 is preferably pivotally mounted on the iupstand 29a for at least limited pivotal movement about a horizontal axis 20' extending normal to, and in this case intersecting the axis of support shaft 13'; and such mounting part 28 is provided or formed integrally with a transverse vertical mounting plate or flange part 28b at its end remote from the bearing 14' and, vehicle hub part 3 and on which the hydraulic pump assembly 17' is mounted so as to have its input drive shaft 18' extend into a cavity or bore 28a defined by the mounting part 28 for co-axial alignment with the bearing 14', and thus the coupling shaft 13' when fitted therein.

Coupling between the coupling shaft 13' and pump assembly input drive shaft 18' is in this case preferably by way of a two part connection including a first part in the form of -12- I r

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4 longitudinally externally splined member 30 mounted on the input drive shaft 18' and engaged with a complementary internally splined and slotted end part of a sleeve connector 31 having its opposite end terminating adjacent or in close proximity to the inner side of the bearing 14' within the mounting part 28; said sleeve connector opposite end being arranged to slidably receive the inner end part 13'a of the coupling shaft 13' in an interengaging manner so as to be rotatable therewith. Again the shaft end part 13'a and re- IOQ spective end of the sleeve connector 31 can be provided with 041 a mating keying spline, square or other regular section, arrangement providing for the required slidable interengagement.

4 S.Preferably the first splined connection part 30 is mounted on the inrit drive shaft 181 and/or the sleeve connector 31 15 mounted on the shaft 13' in a manner permiting shear disengagement in the event of a jam or overload situation in use of S the apparatus, so as to prevent serious damage to the apparatus and/or vehicle eg the first connection part 30 and/or the sleeve connector 31 can be simply mounted as a press or heat shrunk .7Q friction fit, or by means of a shearable key, on the respective

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shaft 18' or 13'. Instead of a two part connection as illustrated the sleeve connector 31 can form the sole connection to the input drive shaft 18" but the described and illustrated arrangement is preferred with the standard coupling 6, shaft 13', bearing 14' and sleeve connector 31 provided as one assembled unit (as shown in figure 11) which is readily slidably axially into position within the mounting part 12 and simultaneously into engagement with the input drive shaft 18'.

-13- I U-.1 I Means are provided to lock the bearing 14' and shaft 13' assembly in position and against accidental disengagement during operation; and in one form of the invention a simple pivotally mounted locking bar 28c is provided on the mounting part 28 at the bearing 14' receiving face to be pivotally movable upwardly to allow insertion or removal of the bearing 14' and shaft 13' (to which the bearing 14' is permanently fitted) assembly, and to be pivotally moved downwardly to the position indic -ated in figure 10 in securing the bearing 14' and shaft 13' 1.0 assembly against disengagement from the mounting part 28 when fitted thereto. Other securing means can be employed.

Further variations provided in this second for,. of the apparatus include construction as independant units each with its own closed circuit hydraulic fluid reservoir 32 for the hydraulic pump 17' and its own heat exchanger 33 for hydraulic fluid -looling, both conveniently mounted on the base support 29. The hydraulic fluid reservoir 32 has feed and return conduits 34 and 35 to and from the pump assembly 17' and with the feed conduits 34 extending into and passing through the .2Q elongate body of the heat exchanger 33 for cooling by cooling water passed through inlet and outlet pipes 36,37 from a supply source passed through the heat exchanger body and over the hydraulic fluid carrying conduits 35 contained therein. The hydraulic fluid reservoir 32 and heat exchanger 33 are shown as separate entities, but it is envisaged that a combination reservoir 32 and heat exchanger 33 can be provided with or within a single housing or body in providing a neat and compact unit with fewer exposed connections. Other parts can be enclosed or housed as required and air cooled heat exchanger .j i :i i 1 ~cmeans can be employed in place of water cooling for the hydraulic fluid.

The apparatus includes a speed transducer 26' positioned in the mounting part 28 in close proximity to the input drive shaft 18 for determining the speed of rotation and transmitting the required electric signal to the electronic signal receiver and display means 27' by way of electrical connection 26'a, and pump operating pressure is arranged to be determined by way of a pressure transducer 25'b in or connected to the fluid 0 regulator/control valve assembly 25' forming part of the pump S assembly 17' which is arranged to transmit an electronic signal by way of electrical connection 25'a to the signal receiver and display means 27'. Preferably the receiver and display means 27' in this case is or includes an electronic computer and visual display unit for interpreting and displaying infor- 0* mation on demand; and the apparatus may also include a hand held remote control unit 27'b operable by an operator as required to instruct the computer receiver and display means as to the information required to be displayed, which may 2. include prescribed comparative test data for any particular make and/or model vehicle. The pump fluid regulator control valve assembly 25' is preferably also electronically adjustable by the operator on operation of the remote control unit 27'b and computer receiver 27' by way of electrical connection 25'c so that the pump loading effect can be increased or decreased within prescribed limits for determination of the connected driving wheel torque at any predetermined speed of operation. The computer will be programmed also to maintain .1 0000 'Itr 0 .0 0 0 0S 0' 0

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90~3 0* 0 0* the required syncronised rotational speed of the vehicle hub parts 3 and pump shaft 18' with automatical electronic control and regulation of valve assembly 25', as for the first described arrangement.

A further modification can include the provision ot, the support base part 29b of a strain gauge or like sensing device 36 for sensing the turning force exerted on the apparatus as a whole on acceleration and/or constant rotation of the drive wheel 2 under test. The base part 29bhaving fixed ground engaging feet 29c to one side of the vertical centre-line of the apparatus,and the strain gauge or other sensing device 36 having a downardly directly ground engaging sensor plunger 36a subject to pressure variation on rotation of the vehicle driving wheel 2 or hub part 3 with the apparatus coupled thereto. The sensing device 36 also being arranged to transmit an electronic signal to the computer signal receiver 27'.

1 .0, As with the first described arrangement, instead of or in addition to the provision of the feet 29c at least one downwardly spring biassed roller(s) or castor(s), or retractable 23. wheel(s) can be provided on the base part 29b to normally project below for moving and manoeuvring the apparatus by itself; and being retractable against the spring bias for stable ground or floor engagement by the base part 29b or feet 29c if provided. Further, the retractable roller(s), castor(s) or wheel(s) arrangement can provide for actuation of electric switch means associated (on coupling of the apparatus to the vehicle 1 and electronic equipment) with the electrical circuitry and actuable to interupt the electric power supply and -16- I prevent operation of the apparatus (and/or provide an audio/ visual warning) if the roller(s),castor(s) or wheel(s) are not fully retracted and the base support 29 not stable on the ground or floor under the vehicle weight. One or more roller(s) or wheel(s) positioned at the vehicle side of the base support 29 (or 16 in the first arrangement) may define a pivot axis foL the apparatus as a whole instead of the described upper pivot axes 20,20' for the upper parts.

It will be appreciated that various of the features of the described and illustrated second form of the invention can be alternatively applicable to the first form described and illustrated, and vice versa.

SAlso, the invention is not necessarily confined to dynamometer apparatus employing a hydraulic pump assembly and assoc- 1, iated hydraulic circuitry as the power absorbing and torque measuring means; and it is envisaged for example that alternat- 9 ive power absorbing devices or apparatus similarly mountable and employable in accordance with the invention could comprise such as an eddy current retarding device, electrical generator, a fluid flywheel or paddle wheel assembly, or friction brake S device.

Thus, by this invention there is provided dynamometer apparatus of a relatively simple nature but providing for accurate measurement and capable of being manufactured and sold at substantially lower costs than conventionally employed dynamometer apparatus for similar work. Additionally, the apparatus of this invention is compact and portable (quick fit connections can be employed for the hydraulic and/or electric circuitry -17- /1 ;l S where appropriate and to facilitate dismantling for storage), and may thus be particularly advantageous in smaller garages and workshops where space is at a premium. The apparatus may be employed for a wide range of low and high speeds and does not suffer the tyre overheating and blow-out risks of roller type dynamometer equipment; and does not employ expensive tyre rollers or involve the usual expensive installation costs of such equipment.

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0 9* O 0 9 0 00 *090 U S The apparatus can be applicable to the torque measurement of single or multiple drive wheel or drive shaft arrangements as may be required.

Some preferred aspects of the invention have been described and illustrated by way of example and with reference to the accompanying drawings, but it will be appreciated that other variations of and modifications to the invention can take place without departing from the scope of the appended claims.

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Claims (19)

1. A dynamometer and mounting apparatus comprising a base support having an upper support and bearing part mounting a bearing assembly which is arranged to detachably and rotatably mount a coupling for rotation of said coupling about a substantially horizontal axis, said coupling having one outer end provided with or arranged to receive a part arranged for rigid connection to a drive wheel, wheel hub or a driven shaft outer end part for axial alignment and direct rotation therewith, and said *coupling having an opposite end part arranged for S*detachable axial sliding connection to the input drive shaft of a power absorbing assembly mounted on and supported by the upper support and bearing part of the Sbase support, said upper support and bearing part being mounted for at least partial pivotal movement relative to the lower base part of the base support and about a S substantially horizontal axis in a plane normal to the axis of rotation of said coupling and said input drive I* shaft and the lower base part being arranged for non-movable support on a support surface when the apparatus is coupled for operation; there being means for measuring the speed of rotation of the coupling and input drive shafts and for measuring and/or computing the power absorbtion of said power absorbing assembly during operation, and to determine the equivalent braking torque 19 '1Y S L M7 L 4 of the connected driven wheel or hub or driven shaft for display on an associated and connected information receiving and display means.

2. Apparatus as claimed in claim 1 wherein said coupling includes a coupling shaft permanently mounted for rotation within said bearing assembly and having an inner end part to one side of the bearing assembly connected to said drive input shaft for rotation therewith, and an outer part projecting from the opposite side of said bearing assembly and arranged to slidably detachably receive a coupling member when fixed to said drive wheel, hub or driven shaft.

3. Apparatus as claimed in claim 1 wherein said coupling includes a coupling shaft having a wheel, hub or Sdrive shaft coupling member fixedly mounted at one end, and an opposite end and medial part which is slidably and detachably locatable through said bearing assembly to have said opposite end detachably engagable with said input drive shaft for rotation thereof.

4. Apparatus as claimed in claim 1 wherein said I* coupling includes a coupling shaft having a wheel, hub or drive shaft coupling member fixedly mounted at one end, a medial part mounting a bearing, and an opposite end part with a connector member fixedly secured hereto and arranged foi axially slidable and detachable engagement with said input drive shaft for rotation therewith, said coupling -haft medial part and bearing being axially 20 I'lS slidably and detachably locatable within an upper part of said base support. Apparatus as claimed in claim 3 or claim 4 wherein said base support upper part is provided with releasable locking means to secure said bearing assembly from accidental detachment wl n engaged therewith.

6. Apparatus as claimed in any one of claims 2 to wherein said coupling member is arranged for mounting directly to a drive wheel hub part of a vehicle with the wheel removed, the hub part having projecting wheel mounting studs .nd said coupling member having stud apertures complementary in size and positioning to said hub part wheel studs.

7. Apparatus as claimed in any one of claims 2 to wherein said coupling member is arranged to be connected to a drive wheel hub part of a vehicle, with the wheel removed, by way of an adaptor plate device; the hub part having projecting wheel mounting studs and said adaptor plate device having stud apertures complementary in size and positioning to said hub part wheel studs; there being a plurality of similar interchangeable ones of said adaptor plate device each with fixing means common to said coupling member but having their stud apertures of a size and spacing complementary to different wheel hub part wheel mounting stud sizes and/or positioning.

8. Apparatus as claimed in claim 7 wherein each said adaptor plate device is arranged and constructed 21 I substantially as hereinbefore described with reference to figure 4 of the accompanying drawings.

9. Apparatus as claimed in any one of claims 2 to wherein said coupling member is arranged to be connected to a drive wheel hub part of a vehicle, with the wheel removed, by way of an adaptor plate device fixed or fixable to said coupling member; the hub part having projecting wheel mounting studs and said adaptor plate device having a plurality of wheel stud receiving mounting pieces which are radially slidable in radial slot parts of said adaptor plate device so as to be adjustable to suit a I: variety of wheel stud positionings. Apparatus as claimed in claim 9 wherein said S. adaptor plate device is arranged and constructed substantially as hereinbefore described with reference to figures 6 and 7 of the accompanying drawings.

11. Apparatus as claimed in any one of the preceding claims wherein said coupling is arranged, constructed and mounted substantially as hereinbefore described with reference to figures 3 and 5 of the accompanying drawings, 12, Apparatus as claimed in any one of claims 1 to inclusive wherein said coupling is arranged, constructed and mounted substantially as hereinbefore described with reference to figures 10 and 11 of the accompanying drawings.

13. Apparatus as claimed in any one of the preceding claims wherein said power absorbing assembly comprises an 22 i.M i 0 hydraulic fluid pressure pump with pressure transducer means arranged to transmit an electronic signal to said information receiving and display means.

14. Apparatus as claimed in claim 13 wherein said hydraulic pump has a variable regulator/control valve for selection of prescribed loading in the pump at prescribed rotational speeds of said input drive shaft. Apparatus as claimed in claim 14 wherein variation of said regulator/control valve to selected settings is arranged to be effected electronically via an operator actuated remote control device associated with said information receiving and display means.

16. Apparatus as claimed in claim 13, claim 14 or claim 15 wherein said base support mounts a hydraulic fluid reservoir providing a closed circuit hydraulic fluid supply source for said hydraulic fluid pressure pump,

17. Apparatus as claimed in claim 16 wherein said base support mounts a heat exchange unit for cooling of the hydraulic fluid fed to and/or received from said hydraulic fluid pressure pump.

18. Apparatus as claimed in claim 16 and claim 17 wherein said hydraulic fluid reservoir and said heat exchange unit are combined with a common housing or body.

19. Apparatus as claimed in any one of the preceding claims wherein said base support is provided with at least one ground or floor engaging roller wheel or castor to facilitate moving and manoevuring when unconnected to a 23 drive wheel, wheel hub or a driven shaft of a vehicle. Apparatus as claimed in claim 19 wherein said at least one roller, wheel or castor is retractably mounted and normally biassed downwardly towards a ground or floor engaging position, said bias being sufficient to permit lift at least a part of the weight of the apparatus but being readily overcome by the weight of a vehicle to which the apparatus is connected to enable retraction of said at least one roller whael or castor and stable ground or floor engagement by said base support.

21. Apparatus as claimed in claim 20 wherein said at least one retractably mounted roller wheel or castor is arranged to effect actuation of electrical switch means providing interuption of an electrical circuit controlling operation of the apparatus and/or providing an audio/visual signal indicating a stable or nn-stable position of the apparatus in operation. 22, Apparatus as claimed in any one of the preceding claims wherein said base support is provided with a 0 sensing device having a ground or floor contacting sensor disposed to one side o, a vertical line intersectinq the axis of rotation of said coupling and arranged -o sense the turning force exortod on the apparatus during operation and rotation of the connected drive wheel, wheel hub or drive shaft and to transmit a corresponding electronic signal to said information receiving and display means. 24

23. Apparatus f or the dynamometer te-,sting of a motor vehicle having multiple driven wheels, s aid apparatus comprising the apparatus according to any one of the preceding clIaims duplicated one for each driven wheel mounting and having a common information receiving and display means for receipt and interpretation of electronic signials from each of said duplicated apparatuls,

24. Apparatus as claimed in claim 23 when dependant upon any one of claims 13 to 15 wherein hydraulic f luid for each said hydraulic pump is supplied froM and returned to a common hydraulic fluid reservoir, Apparatus ao claimed in claim 24 wherein, said hydraulic f luid reservoir is provided With or conne ted to a heat exchanger for cooling of said fluid during operation. 26, Dynamomatar and wounting apparatus airrned, Constructed. and adaptedl Lor mounting Aind use substantially as herectnbeofore described with reference to figures I to 3 and 5 of the accompanying drawings.

27., Dynamometer anid mounting apparatus arx ngodt U: onstructeO and adapted for mmunting and use stbatantially as hereinboforo described with ref erence to figures 8 to of tho accomparlyinq dIraiwinrgs. UATr'f' THIS 24TH DAY OF S TIME3E~ 1991 C-1tSPtet A.trent S-1 loS- InstUItute oi6 -Yi t f Patel Attornleys of Australitk