AU615240B2 - Weighing scale for transporter loads - Google Patents

Description

i- IL-rr 615240 COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION NAME ADDRESS OF APPLICANT: Gerald L. Greer 1300 Westcliff Drive Newport Beach California 92660 United States of America NAME(S) OF INVENTOR(S): c 0 Kenneth J. FILING ADDRESS FOR SERVICE; DAVIES COLLISON Patent Attorneys 1 Little Collins Street, Melbourne, 3000.

COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: Weigning scale for transporter loads S The following statement is a full description of this invention, including the best method Sof performing it known to me/us:r, L.

r It Technical Field The present invention generally relates to a scale for use in conjunction with transporters such as lift trucks.

More particularly, the present invention is directed to a weighing scale for a lift truck which can be mounted on a conventional lift truck to permit lifting, weighing and transporting of goods in a continuous coordinated operation.

10 More specifically, the present invention is directed to an electronic scale particularly designed for use in conjunction with fork lift trucks and the like to per-nit accurate Sgo.. weighing of goods ancillary to the transport from one location to another in various material handling, transportation and manufacturing operations.

Background of the Invention There has been a well-recognized need for fast, P*4 accurate weighing of materials being transported or processed in commerce for a great number of years. For exi ample, when materials are transported from and received at shipping docks, it is often necessary to check the weight to determine that the weight of the materials conforms to tho correct amount of material which is being shipped or received. In other instances piece goods may be counted and packaged according to cumulative weights or batching in chemical plants may be carried out based upon weights of J various component ingredients. All of these various transportation and manufacturing operations have in common the necessity for transporting goods between two locations and determining the weight preferably to fairly stringent accuracies.

For many years the most common approach has been to move the goods by lift trucks while having a floor scale located in prbximity to the transport path. Two types of floor scales have been employed in transporting and weighing operations of this nature. One floor scale alternative is -2to employ a scale having a relatively low capacity which is sufficient to weigh just the pallet, box or other container being transported by a lift truck. Low capacity floor scales of this type may provide good overall accuracy but require time-consuming operations on the part of a lift truck operator. In this respect it is necessary to transport the material to the scale, place the material on the scale, release the material, back the lift truck away from the material and off the scale, note the weight of the material, drive the lift truck back into position to engage r the material, pick up the material and proceed to complete the transport of the weighed material.

An alternative floor scale device employed in the art contemplates a larger capacity floor scale which contemplates weighing both the lift truck and the material at the same time. Although the use of sich large capacity floor scales obviates the disadvantage of the numerous timeconsuming steps noted above, there are attendant disadvantages to this weighing method besides the greater- expense associated with a much larger capacity scale. For example, T, the accuracy of scales is normally rated ,n terms of pounds per 1000 pounds of applied load. As a result, greater inaccuracies are inherent in a scale which is introducing the inaccuracy of weighing an eight or ten thousand pound lift truck in addition to the material load being weighed.

In addition, it is necessary to take into account the weight of the lift truck vehicle at any particular time inasmuch as substantial variations in weight occur as fuel or water are consumed in the case of gasoline or diesel and electric trucks, respectively.

Due to the pronounced disadvantages for most job requirements of floor mounted scales as discussed above, there have evolved a number of scale devices which can be mounted directly on lift trucks, side loaders, order pickers, stacker cranes or other material handling apparatus Sto make possible the simultaneous weighing and transporting of materials. Many cz these truck-mounted scales have been -ICUT-~ II i -1 -3developed specifically for the handling of particular material in a particular operation. In general, lift truck scales have positioned a scale member between the carriage of the lift truck and the forks mounted thereon. The scales are normally similar in having a stationary plate mounted to the carriage of the lift truck and a movable plate which carries the forks. Various types of flexure devices in differing locations, numbers and combinations are employed tj interconnect the stationary plate and the movable plate and to sense minimal relative vertical movements therebetween as by the use of various types of strain gage devices.

Some lift truck scales have employed highly mechanically complex combinations of load supporting arms, equalizing moment arms and reaction moment arms which control the movement and determination of the portion of the relative vertical displacement between stationary and movable plate members which is attributed solely to forces introduced into the system by the application of a load to the forks of the lift truck. In other instances intricate flexures are 8 20 employed to endeavor to control the movement between the rl: stationary and movable plates so that loads applied to the forks are accurately sensed by a load cell. However, the adaptations of these types of lift truck scale devices have exhibited defects or disadvantages in regard to one or more significant performance features.

In some instances the scales have been so complex that the cost is excessive. In other instances the scales are incapable of weighing material to sufficient accuracy to permit usage in some applications or the accuracy varies significantly dependent upon where a load is positioned along the forks c/r as ,etween two or more forks attached to a movable plate member. In other instances, the scales, due to various design features, are unable to withstand dirt, water or environmental conditions to which the lift trucks are commonly exposed or to absorb the shocks and forces which are commonly encountered in what must be considered the rough environmental conditions to which lift trucks and r

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Efforts to design a scale for lift truck devices eliminating these various disadvantages at costs commensurate with the value for varl-ous applications have not to Applicant's knowledge been sup zeesful.

Disclosure Of The In Dl;-on Therefore, an object of the pres~t invention is to provide a transporter weighing device which is of sufficient strength to withstand the rough use, and even an extent of abuse, which is normally encountered in the loading, unloading and transportation of various goods in the transportation and manufacturing industries. Another object of the present invention is to provide a transporter weighing device which embodies a relatively 1.5 non-complex flexure system that is sufficiently rugged to withstand the conditions to which these devices are subjected. A further object of the present invention is to provide such a transporter weighing device which, while having advantageous strength characteristics and employing a simple flexure system, reflects weight of a load with a high degree of accuracy irrespective of the 'placement or distribution of a loar ,K with respect to elements for supporting a load such as a pair of spaced forks.

495 Another object of the invention is to provide a transporter weighing device which has a flexure configuration that is otherwise highly advantageous.

Preferably, the flexures, which are perhaps the most vulnerable elements if the system to damage, are merely 30 bolted rather than welded in place such that they may be readily disassembled and replaced in the field when necessary. It is further preferred that the weighing deov!i,:e allows compensation to provide improved accuracy for extremely high loading conditions by the substitution for part of the flexure elements, with elements having slightly different design characteristics.

Advantageously, the weighing device has a design

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491$ W0O715,GREDAT,0G4,267S6.rcs,4 which does not significantly reduce the load carrying capacity of the transporter by maintaining a relatively short distance between the transporter carriage and the forks or elements for supporting a load to minimise the length of the lever arm tending to tip the transporter, which limits its lifting capacity. The elements for supporting a load such as forks, are preferably mounted directly to a movable plate rather than to a projecting attachment, again to avoid reducing the load carrying capacity of the transporter.

The weighing device is preferably adapted to employ a load cell which is relatively flat as opposed to cylindrical such as to otherwise further avoid reducing the load carrying capacity of the transporter.

Improved stops are preferably provided and the load cell assembly embodies a shock absorbing device to further minimise the possibility of damage during operational applications of forces and shocks. There may be an adjustable mounting of a stationary plate of the device to the carriage of a transporter to precisely position and equally support the plate even though the underlying carriage surface may not be exactly true in that it may be bent or deformed from operational abuse.

The weighing device advantageously employs an electronic 2 load cell which may be readily couplud with various types of electronic display and recordal devices which are available in the industry. It is moreover preferred that the weighing device is relatively inexpensive, durable and easy to maintain in relation to other weighing 1' '30 devices which are available in the industry.

In general, the invention provides a weighing scale operatively interconnected between a powered lifting carriage and elements for supporting a load includes a fixed plate attached to the lifting carriage, a movable plate carrying the load supporting elements, a plurality of flexure assemblies including flexures interconnecting the fixed plate and the movable plate to maintain the S910715,GREDAT.004,26756.res,5 NT, 0 r i -6fixed plate and the movable plate in substantially parallel relationship, stiffener block means limiting bending of the flexures exclusively to portions thereof closely proximate to the plates, whereby movement of the elements for supporting a load by the application of a load displaces the movable plate such that the fixed plate and the movable plate remain in substantially parallel relationship, and a load cell assembly interposed between the fixed plate and the movable plate to convert displacement of the movable plate relative to the fixed plate to an accurate indication of the weight of a load.

Brief Description of the Drawings Fig. 1 is a perspective view of a lift truck scale embodying the concepts of the present invention depicted mounted upon an exemplary mobile lift truck with forks for engaging a load mounted on the spale.

Fig. la is an enlarged depiction of the reverse side of the portion of Fig. 1 designated Fig. la and depicting an exemplary weight indicator positioned for viewing by the operator of the lift truck of Fig. 1.

Fig. 2 is a front elevational view of the scale S depicted in Fig. 1 with the forks for engaging a load removed therefrom and showing particularly the movable 25 plate member.

Fig. 3 is a top plan view of the scale depicted in Fig. 2 showing particularly the flexure assemblies and the load cell assembly.

Fig. 4 is a side elevational view of the scale 30 depicted in Fig. 2 showing additional details of the

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Fig. 5 is a sectional view taken substantially along line 5-5 of Fig. 2 and showing additional structural details particularly of the mounting elements and the overload stops of the scale.

Preferred Mode For Carrying Out The Invention A weighing scale for an industrial transporter according to the concepts of the present invention is generally indicated by the numeral 10 in Fig. 1. As an exemplary transporter on which weighing scale 10 is mounted, there is Sschematically depicted a fork lift truck, generally indicated by the numeral 11. As shown, the fork lift truck 11 has a number of standard components which are generally shown in Fig. 1 and include an operator station, generally indicated by the numeral 12, which is positioned between four wheels 13 which give the truck mobility. The fork lift truck 11 has a vertical piston assembly, generally indicated 20 by the numeral 14, to impart the driving force for lifting and lowering of a load before and after it is transported, respectively. Mounted for vertical movement with the boom I"t' 14 is a lifting carLiage, generally indicated by the numeral in Figs. 3 ana 5, which mounts the weighing scale 10 in a manner described in detail hereinafter.

The weighing scale 10 is operatively interconnected between the lifting carriage 15 and elements for supporting a load such as two preferably identical gorks, generally indicated by the numeral 16. Each of the forks 16 may be of conventional L-shaped configuration, as shown, including a horizontal arm 17 capable of being inserted beneath a load to be lifted and transported by the fork lift truck 11. Each of the forks 16 also has a vertical arm 18 which extends upwardly from the horizontal arm 17 for the purpose of vertically supporting a load reposing on the forks 16 and providin- a means of attachment of forks 16 to the weighing scale 8- As best seen in Figs. 1 and la, the weighing scale is interconnected in a manner well known to persons skilled in the art to an electronic indicator, generally indicated by the numeral 20, which is preferably mounted in proximity to and in such a manner as to be readily viewable from the operator station 12. The electronic indicator has a read-out 21 as seen in Fig. la which may directly depict the cumulative weight on the forks 16 at any given instant. The indicator 20 may have additional inputs, 10 displays, and capabilities which are known in the art for purposes of presetting a known tare weight, giving a digital r« .display of quantities of items of a given weight, accumu- ,t ,lating consecutive loads in a memory and displaying a cumutl lative total, or performing other similar functions.

As seen in each of Figs. 2-5, inclusive, the weighing scale 10 has as two primary components, a pair of generally rectangular frame members including a fixed plate member, generally indicated by the numeral 25, and a movable plate mebl-ier, generally indicated by the numeral 26. As shown, for use in conjunction with a fork lift truck 11 ,adapted to carry a pair of forks 16, the fixed plate mermber is attached to the lifting carriage 15 by a fixed plate mounting assembly, generally indicated by the numeral The fixed plate mounting assembly 30 consists of a plurality of spaced cleats 31, as best seen in Figs. inclusive. As seen particularly in Figs. 2 and 4, each cleat 31 is rigidly attached to the fixed plate member 25 as by a pair of cap screws 32. As shown, there are three cleats 31 with one positioned substantially medially of the width of fixed plate member 25 and the other two proximate the ends. The cleats 31 are provided with a projection 33 adapted to engage a groove provided on the carriage 15 whic.i is normally employed to mount conventional fork elements.

At least one cleat 31 is provided with an anti-shift pin 34 (Figs. 3 and 5) which is adapted to extend into one of a plurality of slots provided in lifting carriage 15 to prevent movement of the fixed plate member 25 laterally or -9widthwise of the lifting carriage 15. The cleats 31 thus provide rigid attachment of the top of the fixed plate member 25 to lifting carriage A different type of attachment is preferably provided as part of fixed plate mounting assembly 30 to affix the lower portion of the fixed plate member 25 to the lifting carriage 15 of the lift truck 11. This is desirable due to the fact that the lifting carriage 15 of most lift trucks is commonly dented, bent or otherwise irregular due 10 to abuse which results from the normal operation of these S devices. If the weighing scale 10 is not uniformly supported stresses may be applied to the stationary plate which may introduce inaccuracies into the weighing function i carried out by the scale 10. This problem may be controlled by providing a three point mounting of the lower portion of the fixed plate member on the carriage As shown particularly in Fi's. 2, 4 and 5, a small mounting pad 35 is positioned proximate the lower extremity of the fixed plate member 25 and preferably substantially medially of the width thereof (Fig. The fixed plate ,r member 25 is also supported proximate each lateral side by alignment bolts 36. In order to provide nonstressed positioning of the fixed plate member 25, the alignment bolts 36 are longitudinally adjustable by being threadably inserted through the fixed plate member 25 as best seen in Fig. In order to preclude accidental rotation of the alignment bolts 36 during the vibration attendant loading and unloading of the weighing scale 10, the alignment bolts 36 may be provided with a locknut 37 which when seated against fixed plate member 25 maintains the bolts at any preset position. Thus, it is to be seen that the fixed plate member 25 may be mounted and secured relative to a lifting carriage 15 in a uniformly supported, substantially unstressed condition.

In order to insure that the lower portion of fixed plate member 25 does not become separated from carriage during operation of the lift truck 11, the fixed plate mounting assembly 30 may include a safety plate 40 (see Figs. 3 and 4) which may be attached to the lower extremity of fixed plate member 25 as by a cap screw 41. The safety plate 40 has an upturned lip 42 which, upon movement of plate 40 perpendicular to plate member 25, fits behind lifting carriage 15 in order to maintain the mounting pad and the alignment bolts 36 seated against the carriage As best seen in Fig. 3, a safety plate 40 of appreciable width positioned substantially medially of the fixed plate S 10 member 25 is adequate to effect the afozredescribed functions.

The weighing scale 10 operates on the premise that the fixed plate member 25 and the movable plate member 26 ire effectively rigid elements and that relative vertical therebetween is a parallelogram type of movement with small displacements being proportional to the weight of loads positioned on the forks 16. For this purpose it is to be noted that the fixed plate member 25 and movable plate member 26 are preferably manufactured of a substantial thickness of steel, such as to undergo minimal distortion over the range of loading capacity to Which the weighing scale 10 is to be operative. The parallelogram relationship between the fixed plate member 25 and the movable plate member 26 is established by their interconnection by a plurality of flexure assemblies, generally indicated by the numeral 45, interposed therebetween. As best seen in Figs.

2f 3 and 4, the flexure assemblies 45 are pref~erably arranged in symmetrical fashion generally proximate the top and bottom of the plates 25, 26 near, the lateral extremities thereof. Depending upon the loading characteristics of a particular weighing scale 10 additional flexure assemblies could be employed.

As shown, each of the flexure assemblies 45 employs as the bending component a flexure 46 which may be a thin sheet of metal, preferably stainless steel, which is punched to receive fasten~ers as described hereinafter and subsequently processed to eliminate irregularities which 1/ -11- II 4 4 44 $4 4 444 4$ 4$ 4 444 4 *4 4 4 4* 4 4 4* 4 4 4 '4 4 4 t 4 *44 4 4 could produce fissures or fractures in the material. The flexures 46 are mounted in elongate cutouts 47 and 48 in the fixed plate member 26 and movable plate member 26, r,,spectively. The cutouts 47, 48 are desirably accurately milled for precise positioning as between the plates 25, 26. The flexures 46 are mounted in the cutouts 47 and 48 by cap screws 49. The cap screws 49 carry clamp blocks 50 which are of substantial thickness to maintain the flexures 46 in absolutely planar alignment within the cutouts 47, 48, 10 In order to provide the aforedescribed parallelogram motion between plates 25 and 26, the flexures 46 must remain substantially rigid medially thereof. For this purpose each of the flexures 46 is provided with a pair of sti~ffener blocks 52 and *53 which are fixedly positioned to either side of said flexures 46 by a pair of cap screws 54 which extend therethrough. The stiffener blocks 52, 53 extend from proximate said fixed plate member 25 to progimate said movable plate member 26. It is thus to be appreciated that the bending of the flexures is limited by both 20 the stiffener blocks 52, and 53 and the clamp blocks 50, such as to be restricted sole4,y to the unsupported areas proximA-, the inner surfaces of! the plates 26 and outwardly ne stiffener blocks 52 and 53.

The vertical displacement of the movable plate member 26 relative to the fixed plate mnember 25 is measured and converted to a weight representation by a load cell assembly, generally indicated by the numeral 60, which is interposed between the plates 25, 26. Referring now particularly Lo Figs, 2, 3 and 4f the upper extremity of' load cell assembly 60 has a bifurcated bracket 61 which is rigidly attached. to the fixed plate member 25 as by a Weld1ment 62. The bracket 61 has spaced ears 63 which are bored to receive a pin 65 which extends therethtough and, is retained in position by snap rings 66 positioned near either axial extremity thereof and outwardly of the ears 63. The pin 65 is preferably of hardened steel and suspends a yoke which extends downwardly therefrom. The yoke 70 may have -12flaring conical bores 71 extending from the center thereof to provide an extent of universal movement between said pin and said yoke 70. The yoke 70 is threaded to receive a threaded stud 72 projecting therefrom which is threaded into an upper leg 73 of a strain aqe load cell 75. The position of the load cell leg 73 relative to the yoke 70 once established is maintained by a locknut 74 on the stud 72 which engages tho leg 73 of the load cell Referring to Figs. 2 and 4, the load cell 75 of S 10 load cell assentibly 60 is interconnected to the movable plate :Its member 26 by a lower extremity including a bracket 80 which is rigidly attached to the movable plate member 26 as by a weldment 81 (see Fig. The load cell 75 and particularly a lower leg 76 thereof interconnects with the bracket 80 by virtue of a stud 82 which is threaded into the lower leg 76 of load cell. 75. In a manner comparable to the stud 72, the stud 82 carries a locknut 83 which engages the lower leg 76 of load cell 75 to maintain the stud in fixed axial position relative thereto once the assembly is appropriately ad- 2 0 justed. The stud.72 at the end opposite load cell carries a ltoad ball 84 which is positioned in a conical cutout 85 in the bracket 80. The position of the load ball 84 along the stud 82 with respect to bracket 80 is maintained by a locknut 86 positioned on stud 82 axially outwardly of the load ball 84 to maintain the preset alignment of the componentpk. of the load cell assembly 60 once appropriately adjusted.

For purposes of averting posz !blo damage to load cell assembly 60 in the event of Verticaltly upward shock loading of the movable plate member 26, the stud 82 carries between bracket 80 and load cell 75 a rubber bumper 87 which operates as a shock absor~ber. The bumper 87 may be positioned and adjustably precom9ressed with respect to the bracket 80 by a washer 88 and locknut 89 positioned thereabove on Stud 82. Thus the weighing scale is protected from damage In the event the forks 16 whilo being lowered are accidently dropped or slammed into the floor or other object.

-13- As can be appreciated particularly from viewing Figs. 3 and 4, the design of the flexure assemblies 45 and the load cell assembly 60 is such that only minimal spacing is required between the fixed plate member 25 and the movable plate member 26. This is significant in providing a weighing scale which does not significantly reduce the load carrying capacity of a transporter. The further the forks 16 which carry a load are mounted outwardly of the carriage o 15, the lesser the load which can be positioned on the forks 16 before producing a turning moment which will tip the o'w transporter.

In addition to the rubber bumper 87 associated with the load cell assembly 60 to prevent damage from upward S shock loading of the movable plate member 26 relative to the fixed plate member 25, there are other safety stops which are desirably provided to prevent damage or loss of control of a load when the weighing scale 10 is overloaded or a component fails. In order to keep the plates 25, 26 from separating in the event of overloading or component failure 20 the weighing device 10 may be provided with plate separation stops, generally indicated by the numeral 90 in Figs. 2 and 3. Each plate separation stop 90 consists of a bolt 91 t which is threaded into a bore 92 in movable plate 26. The bolt 91 passes through without engaging a bore 93 in the fixed plate member 25. The bore 93 is concentric with a larger counterbore 94 which freely houses the head 95 of the bolt 91. The bolt 91 reposes during normal operation of weighing scale 10 in the manner depicted in Fig. 3. In an overload condition tending to separate the plates 25, 26, 33 the bolt head 95 bottom in counterbore 94 to limit separation of the plat 4 A locknut 6 is provided on bolt 91 to maintain it threaded into movable plate member 26 a desired preset distance to permit a predetermined extent of separation between the plates 25, 26 before the bolt head bottoms out on counterbore 94. While two plate separation stops 90 are shown by way of example in Fig. 2, (with the details of one being shown in Fig. 3) it should be appreciated that more or less of these stops may be provided depending upon the size and loading requirements of a particular weighing scale A further safety stop desirably provided to prevent damage to the weighing scale 10 is to avoid crushing when the forks 16 of lift truck 11 engage a heavy or immovable object at any appreciable speed. In order to prevent the movable plate member 26 from moving toward the Sr, fixed plate member 25 such as to possibly damage the flexure 10 assemblies 45 and the load cell assembly 60, the weighing device 10 may be provided with bumper stops, generally indicated by the numeral 100. As best seen in Figs. 2 and 5, a bumper stop 100 consists of a bumper bolt 101 which is 0 threaded into a bore 102 in the fixed plate member 25 with the head 103 of the bolt 101 projecting a substantial portion of the distance between plates 25 and 26 to a position proximate the inner surface of movable plate member 26.

The head 103 of bumper bolt 101 is positioned such as to restrain travel of movable plate member 26 toward fixed plate member 25 before appreciable damage can be done to the flexure assemblies 45 or the load cell assembly 60. Once an appropriate positioning of bumper bolt 101 is achieved, a locknut 104 carried by the bolt l'l is moved into locking engagement with the fixed plate member 25. While two bumper stops 100 are shown by way of example in Fig. 2 (with the details of one being shown in Fig. 3) it should be appreciated that more or less of these stops may be provided depending upon the size and loading parameters of a particular weighing scale The movable plPte membe!i 26 is provided with suitable structure fr- f he mounting of forks 16 or other elements for supporting a load outwardly thereof. For exemplary purposes, the upper extremity of movable plate 26 is provided with an offset 110 for receiving a conventional suspension portion of forks 16 (see Fig. In addition, Figs. 2 and 3 show a plurality of spaced slots 111 across the upper portion of movable plate member 26 which are adapted to receive clamping members on conventional forks at various positions laterally of the movable plate member 26 in a manner well known to persons skilled in the art. It is to be appreciated that other known mounting structure may be provided for other elements for supporting a load. It is to t3 noted, however, that it is advantageous that the elements for attachment of forks 16 be integrated in the movable plate 26 as opposed to a member projecting outwardly there- Sfrom. This prevents reducing the load carrying capacity of the lift truck 11 for the same reasons as those described S' above in conjunction with spacing between fixed plate member oft 25 and movable plate member 26.

'Thus it should be evident that the weighing scale disclosed herein carries out the various objects of the invention set forth hereinabove and otherwise constitutes an advantageous contribution to the art. As may be apparent to persons skilled in the art, modifications can be made to the preferred embodiment disclosed herein without departing from the spirit of the invention. For example, in instances where the application contemplates repeated handling c extremely heavy loads it has been found to be advant to use flexures 46 in the lower assemblies 45 which arE slightly longer than the flexures 46 in the upper asse s This allows the flexure- 46 in the lower flexure Isemblies 45 to compress slightly and the flexures 46 in tlhe upper flexure assemblies 45 to elongate slightly to more precisely maintain the parallel relationship of the fixed plate member 25 and the movable plate member 26, thus effecting improved weighing accuracy. This and other modifications may be carried out within the contemplation of the present invention, the scope of the invention being limited solely by the scope of the attached claims.

Claims (2)

1.6 in substantially parallel relatioipship, and load cell 17 assembly means interposed between said fixed plate 1? means and said movable plate means to convert dis- 19 placement of said movable plate means relative to said fixed plate means to an accurate indication of the

22. weight of the load. took. 2# A scale according to claim 1 wherein each of said flexure means is a sheet material with said stiffener 0 9.3 blocks being fixedly positioned uc, either side of each of said flexure means and extending along said flexure 01:4, means from a position proximate to said fixed plate Q,6 means to a position proximate to said movable plate .7 means. *44 to 2 Ot 1 3 A scale according to claim 2 wherein fasteners rigidly *t 2 interconnect said stiffener blocks and said flexure 3 means. 1 4. A scale according to claim 1 wherein said flexure 2 mea-s are of sheet material and are attached in cut- A3 outs in said plate means. 17 1 5. A scale according to claim 4 wherein said flexure 2 means are attached to said plates within said cutouts 3 by fasteners, said fasteners mounting clamp blocks 4 within said cutouts overlying the portion of said flexure means proximate a surface of said plate means. 1 6. A scale according to claim 5, wherein said clamp 2 blocks overlie substantially the entirety of said 3 flexure means within said cutouts. 1 7. A scale according to claim 1, wherein said flexure 2 means are positioned at a plurality of spaced lateral- 3 ly planar locations proximate the top and bottom of 4 said plate means. 1 8. A scale according to claim 7, wherein said flexure 2 means proximate the bottom of said plate means are 3 slightly longer than said flexure means proximate the 4 top of said plate means, whereby said movable plate means and said fixed plate means are maintained sub- 6 stantially parallel when supporting a load which is 7 relatively heavy in relation to the capacity of the 8 scale. i: .t 1 9. A scale according to claim 1, wherein said load cell 2 assembly means has one extremity attached to said fixed plate means and the other extremity attached to t. "4 said movable plate means. t1 10. A scale according to claim 9, wherein said load cell 2 assembly means is of a narrow design to minimize the p 3 distance between said fixed plate means and said mov- 4 able plate msans. 1 11. A scale according to claim 9, wherein said extremity 2 of said lead cell assembly means attached to said 3 fixed plate means has a yoke with a bore suspended on 4 a pin mounted on a bifurcated bracket attached to said fixed plate means for movement between said load cell /o 6 assembly means and said fixed plate means. ~18 1 12. A scale according to claim 11, wherein said bore in 2 said yoke is spherical to provide substantially uni- 3 versal movement between said load cell assembly means 4 and said fixed plate means. 1 13. A scale according to claim 11, wherein said yoke is 2 threaded to receive a stud which is attached to a 3 strain gage load cell. 1 14. A scale according to claim 11, wherein said extremity 2 of said load cell assembly means attached to said 3 movable plate means has a stud extending through an 4 aperture in a bracket attached to said movable plate means with a load ball on said stud positioned in said 6 aperture. f. 1 15. A scale according to claim 14, wherein said stud car- 2 ries shock absorber means mounted between said bracket 3 and a load cell to protect said load cell from severe 4 reverse loading forces. 1 16. A scale according to claim 15, wherein said aperture 2 in said bracket is conical and said load ball has a 3 curved surface for self-alignment relative to said 4 bracket. I, I 1 17. A scale according to claim 1 having plate separation 1*11 2 stop means including a bolt attached to one of said 3 plate means and freely passing through the other of S4 said plate means, whereby the head of said bolt engag- es the other of said plate means upon application of S 6 overload conditions tending to separate said plates. 1 18. A scale according to claim 17 having bumper stop means 2 adjustably mounted to project a substantial portion of S3 the distance between said plates to restrain excessive 4 travel of said movable plate means toward said fixed plate means. 19 1 19. A scale according to claim 1, wherein the elements for 2 supporting a load are mounted directly on said movable 3 plate means. A scale substantially as hereinbefore described with reference to the accompanying drawings. Dated this 12th day of July, 1991. Gerald L. Greer by DAVIES COLLISON Patent Attorneys for the applicant(s) S* i t It,