US2940746A - Portable scale mechanism - Google Patents

Description

June 14, 1960 w. c. ANDERSON ET AL 2,940,746

PORTABLE SCALE MECHANISM Filed Oct. 21, 1955 3 Sheets-Sheet 1 IN V EN TORS WI Carb mterson By Sydney L.Deweg AT TORNEYS June 14,' 1960 w. c. ANDERSON x-:rAL 2,940,746

PORTABLE: SCALE MECHANISM Filed oct. 21, 1953 s sheets-sneer 2 2o 4 la l0 25 21 '6 INVENTORS WCarLndersonw F 3 BY SgdnegLeu/ey 'Za gcuua ATTRNEYS June 14, 1960 w. c. ANDERSON x-:TAL 2,940,746

`PORTABLE SCALE MECHANISM Filed Oct. 21, 1953 5 Sheets-Sheet 3 INVENTORS Wwrbndersona, 35 I4 6o 52 64 38 BY SydneyL.Deu/eg -ATTRNEYS United States Patent (l) PORTABLE SCALE MECHANISM W Carl Anderson and Sydney L. Dewey, Canton, Ohio,

assignors to The Union Metal Manufacturing Company, Canton, Ohio, a corporation of Ohio Filed Oct. 21, 1953, Ser. No. 387,458

12 Claims. (Cl. 26S-.440)

The invention relates to scale mechanisms and more particularly to a portable scale mechanism which is espe cially adapted for use with a lift truck, such as a fork or platform lift truck, for performing a weighingoperation during operation of the truck, as by being constructed as a part of the lift truck, or as by being constructed as a separate unit for use as anattachment or an accessory foralift truck. y

Many types and kinds of materials are handled and transported daily in all types, kinds and fields of industry. A great deal of such handling is performed by lift trucks and particularly by fork lift trucks. In many instances, it is necessary to determine the weight of the material handled at some time during handling. Normally, such weighing operation in lift truck materials handling is carried out by transporting the load on the truck to a scale at a fixed location, known as a dormant scale, depositing the load on the scale, weighing the load, and then removing the load from the scale for further desired lift truck handling.

For instance, in the operation of a foundry certain materials are charged to the cupola `for melting. Materials handling boxes may be used for accumulating the material to be charged and these boxes normally are handled on a fork lift truck and the contents thereof dumped by the lift truck into the cupola or a cupola charging bin. In such operations, it is necessary to deter' mine quite accurately the weight of the various materials forming a part of the cupola charge. Heretofore, the weighing of materials handled in materials handling boxes and by a fork lift truck for charging a foundry cupola has been a relatively expensive but essentially non-productive operation.

Accordingly, it is a general object of the present invention to provide a scale mechanism which can be associated with a lift truck in such manner that as material or a load to be handled is picked up by the lift truck for transportation, a scale reading can immediately .be obtained indicating the weight of lthe material or load handled, without the necessity of carrying the material on the lift truck to some dormant scale.

This problem is complicated by a number of factors. First, the inherent design of a lift truck for universal use requires that the platform or fork member thereof must have a minimum height or thickness so that the same may be entered into the low clearance space provided on a skid or pallet or box for picking up the latter when free standing on the ground-or oor. If it is attempted to use the usual lever mechanism of a platform scale that is provided therein below the platform of a platform scale mechanism and to incorporate the same as a part of the forks or platform of a lift truck, the vertical lift truck platform dimension limitations would be exceeded so that it is impossible, as a practical matter, to enter such a scale platform with scale lever mechanism beneath, into a small fork entry clearance space provided in skid platforms, material handling boxes, pallets, etc.

Second, usual platform scale mechanisms involve the '2,940,746 Patented June 14, 1960 use of knife edges for the lever suspensions of the scale mechanism.' However, such knife edge mountings are impractical for use in a device carried or transported by a lift truck because of their fragile nature and the possibility of damage thereto by the severe abuse to which a lift truck is subjected in normal operation. This abuse may result from uneven surfaces or holes or the like in iioors or the ground over which a lift truck may travel, or from quick turning of the lift truck, or from the raising or lowering or the starting or stopping of such raising or lowering of the load on the truck, and from bumping the load during truck manipulation or travel.

Third, if, for space saving, weighing mechanism levers or other devices are to be eliminated from beneath the scale load supporting table or platform, then the load supporting table or platform must be mounted in some manner at one side thereof to suspend it from or otherwise connect it with the weight indicating or recording mechanism and such condition introduces three further problems. The yfirst problem is yrelated to the offset location of the load center on the platform in respect to the side mounting of the platform which tends to tilt or rock the platform with respect to a selected' point in the side suspension thereof. The second problem is related to the degree of offsetting of the offset location of the load center vwith respect to the side mounting of the platform; The third problem is related, viewing the front of the' scale platform and looking toward the olfset suspension means at the rear thereof, to the lateral offsetting of the load center on the scale platform with respect to a plane passing vertically through the platform centrally from front to rear.

degree the true vertical load component or dead weight of the load to be transmitted to the weight indicating l mechanism.

In other words, the problem is one of applying a load at any position on a cantilever type platform and of obtaining a true indication of Ithe load weight at the weight indicating mechanism from which the platform is suspended, regardless of the location or position of lthe load center on the platform; and of at the same time providing a platform of minimum thickness, and of providing suspension mechanism therefor which may be subjected to severe abuse in operation on or as a part of a lift truck without introducing errors in the indication of the true weight and without requiring substantial and continuing maintenance and repair to components of the scale mechamsm.

We have discovered that these complicated problems may be solved and the indicated difiiculties overcome by providing a portable scale mechanism in which an upright standard is provided, which may either be L-shaped to locate means'on the horizontal leg thereof for engage ment by a lift truck fork or platform, or may be incorporated as a part of the fork or platform carriage of a lift truck; in which a weight indicating mechanism is suspended from the upper end of :the upright standard; in which an L-shaped weighing platform member is suspended from the weight indicating mechanism; in which the horizontal leg of the L-shaped weighing platform member forms the load supporting member; in which the vertical leg of the L-shaped weighing'platform member is suspended from the weight indicating mechanism closely adjacent the upright standard; and in which parallel and substantially horizontal reacting means are provided at spaced positions both laterally arid vertically of the upright standard maintaining the vertical leg member of the Lfsbaped weighing platform member against-transmitting'any'vertical components to the weight indicating 'mechanism from said horizontally reacting means and absorbing in a substantially frictionless manner `the hori- Zumal @macnews Off tiltinsfarces imparted tetheweiehin'g platform 'by aload applied to theQweighingplatforrn `.offset with respect to'thel vertical platformleg "j Accordingly, vit is ya further object ofthe present invention to provide av scale mechanismin which theQusiial l lever mechanism of a, platform scale locatedbelowfthe platform is eliminatedwand v in which scale mechanism knife' edge lever suspensions are eliminated.

Furthermore, it is anobject of the presentinventionto l provide a new scale mechanism which maybe inexpen- Qanism 'with vmeans for absorbing horizontal load com' ponents 'imparted to the platform by offset locationfof a load to be .weighed on the weighing platforr'n, so as t0 give atrue load reading at, the weight indicatirigmechanis.rr`1

Fufthsrmare. itisansbiect of the.presentinvemionto AProviflea prtable. .Scale ,mechanism ,which maybe incar- "named-. @1S aprtfofgthe, construct-'1.911. Qi a,.1i.ffftruck.,0r inlay .bpickd 11n bvba. lfttrucksi accessqryeauipment, ,for accurately `weighing a load Ypicked up orhandledby the, lift trucklandwhich is unaffected as to' accuracy by the normal abuse to which a lift truck is subjected in usual operation, or by varying atmospheric conditions'.

*Moreoven it is an'object of the` pre'sentv invention to i provide a new scale mechanism in which a cantilever type 'weighing platform is suspended vertically from a weight indicating mechanism, in which means is provided for Elghaldina Sah'rlatform suspended in suchmannerthat "only'true orj .actualjvertical components of 'the' load are transmitted to the Weight indicating mechanism-to register ,allaccilfate Weight, indisationrandin which a' minimum 'amsunt "Qf'frictmwhh other .1 j. 011ml gandlvertial; load CQmrQn/enfsaffecung ,the accujracy o-ffthe indicator reading, isdevelopedin said' last @mentioned means in, maintaiiiinsthe h'ns p vproper suspended position. i

anaemia #indicating mechanismrhorizontallyreacting/means engaging between the platform member and the upright member absorbingl'lori'zontal load Ycomponentsl imparted to the platform mem-ber by a load applied at any olfset position on the horizontal leg of the platform member; and said standard being adapted to be integrated with the fork or platform carriage of a lift truck, or to be mounted on a base to be picked up by-.the fork or platform of a lift truck.

By way of example, the improved scale construction zofithe-.presentainvention is-shown.in-thesaccompanying Fig.. 6 is a, frag 1rie ritary sectional View. taken on the Fig.v 7 is a top plan View of the unit shown in Figs; 3,

i f 4 and 5 vwith certain parts removed; and

rig. 3;

`"Figi 8 isA a-plan sectional view taken on the line tif-8,

' Similar numerals refer .to similarparts throughout 4the various .figures lof the drawings.

Although he irripiovedscale mechanism of the present inventioisfjillustratcd v 1f1d`describedVv as forming a part of afportable scale,v it 'isto be understood that the irn- 35 istru'ction 'oli'donnant scales.

proved'rnechanismfalso maybe incorporated in the con- "Furthermore, the improved scale mechanism for convenience is Villustrated inthe drawings as incorporated in a portable sc ale attachment or accessory for a fork lift truck, but'it is to ybe understood 'that the same also may be' incorporated direptly as apart ofthe forlc carriage of a1forlclift truck.V /Ayforkjlift-truclc1s indicated generally at 1' handling a scaleunit generally indicated at' 2 incorporating the improved-scale mechanism oflthepresent invention, the unit 2 vbeing constructedffor use as an attachment or accessory fonaffcirl lift truck.

the indicated problems existing in the a rt,` toj'e 1 i 1 a te the d iiiicultiesstated, to generally improve Athe construc- Vtion and facility of accurate use of ascal'eon alifttruck, and to obtain theforegoing advantages and desiderata'in `a simple and -eifective manner. These and other objects and advantages apparent rto those skilled in the art from the following description and claims may -be obtained, the stated results achieved, and the described difficulties overcome bythe'constructions, combinations, subcombinations parts, elements and l.arrangements which comprise the present invention, the nature of which is set forth in the 'following generalstatement, a preferred embodiment of Which-illustrativepf vthefbest imodeinwhich applicants have contemplated applyingthe principlesfis set forthpfin the following descripton and shown infthe drawings, and which` are more particularly and distinctly pointed out and set forthjin -the appended claims forming part hereof;

'The nature` of theimprovements: in portable spale -mechanismsofethe presenty invention may be' ta d in general'termsasiy including -arr-uprighty standard'H embe'lrpa 'Weight indiwtins 'mechanism suspendedg-frsmztheupper 'and fsaid uprishtmmib'er, ,an Li-S'hap d 'antilever ype Ves in ausnalj'mauerl fand'nniastf4 on which -thefOrlc carriage ismounted for raising and? ioweripg "esuarforr members s. irrite 1in truck' mast 4 and' fork members 5' are illustrated in dot- .W1`1mthe scaleunitisnconstructed as a portable scale unit for a `fork lift truck, Zthe standard member 6 isalsopreferably lu shap ed as,shown in the drawings. Alweight indicatingtmechanism.generally indicated at 8 is Suspended ;.f1.`Q1.11' he Standard inemibert'sandain turn suspends. the plattomi member -7 .,belDWZ inarmanner toghe .described in detail 5 TheA standard member.6,*assho-w.n,1includes an upright aleg9. andffafbasealeg-ltl, andthe upright leg 9 -isv formed :of fspaced'uprightchannel-'membersall connected at thev top ebyfanfangleernember 12 and intermediate-their"endsby a ehannei'member113andwitlrfront and rear plates 14 and ke rameincrosssectiom the parts 13; 14 ndl helnametaland Welded tgsether 1 gQ10.-,.0f ,the..,standard,memberv -6 is.. also retenir. fr, ad .inangesehene@essere,ligand upper and lower plate members 17 and 18 also forming a box-like shape in cross-section (Fig. 4).

The standard upright leg 9 and base leg 10 are preferably joined by a mitered joint which may include an angularly located plate 19 welded to the lower ends of plate members 14 and 115 and channel members 11, and also welded to the rear ends of plate members 17 and 18 and channel members 16 to form a stiff and strong angular joint at the base of the standard member 6. If desired, the rear plate member 15 may be bent at its bottom corner and formed as a continuation of the bottom plate member 18. Similarly, the front plate 114 may be bent at its lower end and formed as a continuation of upper plate 17. The front ends of the spaced channel members 16 preferably are cut off at an angle and the bottom plate member y18 may extend upwardly, as indicated at 20 covering the front ends of channel members 16. When the unit is free standing, the bottom plate 18 of the base leg 10 rests on the floor indicated by the oor line 21.

Two spaced channel members 22 and 23 are mounted on the top plate 17 of the base leg 10 and project laterally from the top of the base leg 10 -in an Outrigger-like manner, the projecting undersides' of channel members 22 and 23 preferably being closed by plate members 24 forming fork engaging means, underneath which the fork members 5 of a fork lift truck may be projected so as to engage members 22 and 23 (Figs. 3 and 4) for lifting the standard member 6 on the fork lift truck as shown in Fig. l.

The Outrigger fork engaging means may be supplemented by laterally projecting angle members 25 which extend laterally outwardly near the lower corner of the upright standard 6 from the channel members 12 thereof and these members 25 also protect the platform member 7. Another angle member 26 may be secured to angle members 25 and the rear plate :15 by knee braces 27 to form a rearward abutment for properly locating the scale unit 2 with respect to the truck mast 4 when the scale unit 2 is being handled by the fork lift truck 1 (Fig. 3). The upright leg of the angle member `26 may, if desired, be engaged by a movable member 28 (Fig. 3) on the mast 4 for holding the scale unit 2 on the fork carriage when the fork carriage and scale are being withdrawn from underneath a skid platform or the like being handled by the lift truck. A projecting plateV 29 also may be provided, mounted with knee braces 30 on rear plate 15, if desired, to properly locate the scale unit 2 with respect to lift truck member 28 when locking the scale unit 2 to the lift truck.

A yoke member 31 is mounted centrally at the upper end of the standard member 6 projecting forwardly from angle member 12, and a pivot pin 32 is mounted in yoke member 31 from which the weight indicating mechanism 8 is suspended by an ear 33, the pivot joint between ear 33 and pivot pin 32 being loose and universally flexible.

The platform member 7, as' indicated, is L-shaped and cantilever-like and preferably includes laterally spaced upright leg portions 34, and laterally spaced horizontal fork-like weight receiving leg poltions 35. Each of leg portions 34 and 35 may be box-like in cross-section, as shown; and leg portions 34 and 35 are joined by a mitered joint 36. The front ends of horizontal leg portions 35 may be connected by a box-like front member 37 holding the fork-like leg portions' 35 spaced apart at a location generally above the location of the forks 5 of the lift truck (Fig. 4).

As best shown in Figs. 6 and 8, the laterally spaced upright leg portions 34 of the platform member 7 are located laterally adjacent the upright leg 9 of the standard member 6. The upper ends of the upright leg portions 34 are connected by a front cross plate member 38 which lforms a saddleelike arrangement in cross-section, with leg portions 34 (Fig. l6), so thatthe plate 38 straddles the standard member upright leg 9.

Spaced bosses 39 are mounted on the upper edge of cross plate 38, adjacent cutout portion 40, and a pivot pin 41 is journaled in bosses 39. The pivot pin 41 is pivotally connected with a suspension member 42 of the weight indicating mechanism 8, the pivot joint between members 41 and 42 being loose and universally flexible.

'lhe weight indicating mechanism 8 may be formed of any usual construction preferably having a dial scale 43 with a pointer `44 actuated to indicate a weight reading by deeotion or movement of the suspending member 42. Although the deflection of the suspending member 42 in various types of weight indicating mechanisms on the market, when the mechanism is loaded, may be small or considerable, it is preferred in accordance with the present invention to have the deflection of member 42 as small as possible such as a few thousandths of an inch, say .020 for example, although it is to be understood that tnis deflection may be larger depending upon the particular type of Aweight indicating mechanism utilized.

In accordance with the present invention, a channel member 45 is mounted at the upper end of each upright leg portion 34 of the platform member 7 projecting for-v wardly outwardly, and a block 46 is mounted at the top of Ithe forward end of each member 45. A U-shaped bracket y47 is mounted at each side of the upright leg 9 of standard member 6 adjacent each block 46 (Fig. 3) and a chain-link 48 is connected between the bracket 47 and block 46 by a pivot pin -49 and an eye member 50, the location of the eye 50 with respect to block 46 being adjustable by nuts 51 threaded onto the end of eye member 50.

The chain-link 48 thus forms a chain-link means universally flexible in all planes connecting the upper ends of the standard 4and platform members 6 and 7 together; and the pivot joints' at the ends of the chain-link means 48 in accordance with the invention are loose and universally flexible.

Viewing Figs. 3, 4 and 7, the chain-link means 48 constitute a pair of spaced, parallel, upper, horizontally reacting chain-link connections between the upper ends of the standard and platform members.

Referring particularly lto Figs. 2, 3 and 8, a channel member 52 is connected laterally between the rear ends of the platform member leg portions 35; and the forward flange of member 52 is' cu-t out at spaced regions as indicated at 53. U-shaped brackets 54 are mounted within the vchannel 52 on the rear leg thereof opposite the cutout portions 53. Likewise, a block 55 is mounted on the channel member 22 on standard member 6 forwardly of each bracket 54 (Fig. 8); and a chain-link 56 is connected between each bracket 54 and its corresponding block 55 by a pivot pin 57 and an eye member 58, the location ofthe eye 58`with respect to block 55 being adjustable by nuts 59 threaded onto the end of eye members 58.

The chain-link 56 thus forms a chain-link means universally flexible in all planes connecting the lower ends v of the standard and platform members 6 and 7 together;

and the pivot joints at the ends of the chain-link means 56 in accordance with the invention are loose and universally flexible.

Viewing Figs. 3, 4 and 7, the chain-link means 56 constitute a pair of spaced parallel, lower, horizontally reacting chain-link connections between the lower ends of the standard and platform members; and the two pairs of chain-link means 48 and 56 constitute spaced pairs of parallel upper and lower horizontally reacting chain-link means connected between the platform and standard members.

Referring to Figs. 5 and 6, a lug or boss 60 is mounted on and projects rearwardly from the front cross plate member 38 at the top end of the platform member 7; and two spaced U-shaped brackets 61 are mounted on the upright channel members 11 of standard member 6, laterally opposite the lug 60. The center link 62 of 7 chain-link 63 (Fig. 6) is welded to lug oil and the ends of wchain-li-nkl are connected by pivo-t pins 64.'- to-brackets '6.

Thefchain-linkr thus-'forms a chain-link meansvuni- .z-s'ersall'y flexiblefin fall. planes 'laterally `connecting the up- :rper' ends'o'fLthestandardand platformrmembers 6 `and 7 nftogethergf. andthe pivot joints at. the ends 'of theVfchain-link Epmeans 631m `accordancewith` the .invention are loose and univer-s a'lly.- flexible.

i..1Referrir.igfto-,Figs. .2,- 4, 7-. and 8,r a lug. or.boss.,65.fis

mounted centrally on: the upper vplatememberf171;.of :the

.,base legltlof standard member 6 Tand. Ugshaped brackets f6.6 are .mountednon and project inwardly fromheinside vof platform .member leg .portions .35s laterallysopposite: lug .65. The-.centerdinlc.67..of.chaimlink 68 is welded .to `lug a;.'.65.\.and.the.ends of .chain-link..68 1are connected. by pivot .pins .69 .withbracketsgd f The chain-link ,168;thus forms..a;;chain-link means uniyersa'lly flexible..` in-allV pla-nes laterally-.connecting the lower ends .ofthe standard .and .platform members 6;. and 7. together; vand ,the pivotjoints at .the ends ofthe chainlinlrmems- 6% in accordance with the invention are loose .and universally flexible.

The chain-link means 63 and 68 constitute spaced Iupper and lower, laterally extending, horizontally reacting chain- .link connections between the upper and lower ends of 1the standard and platform` members. f

Furthermore, the chain-link means 48 and Sidwhich extend foreand aft of the scale. unit, `and the laterally extending chain-link means 63 and `titi restrain and hold platform member 7 'in the desired position suspended from the weight indicating mechanism 8 and absorb horizontal components of tiltingy forces imparted- ,tothe platform i.member by. a loadapplied at any offset position on the weight vreceiving leg portions 35of the platform member. All of the chain-link. means 48, S56, 631 and 68 when subjected to load act as tension members, the chain-link meansdi and Sobeing in tension at all times even when ,the scale unit 2 is freestanding because of the inherent tilting. moment .imparted thereto by the cantilever lconfstructlon lthereofY suspendedfrom .the weight' indicating 'mechanism at the top of the upright leg portions 34 thereof.

if desired, stop or guide lugsV@ may bernounted on standardmember channel23 slightly spaced from and vjust inside of the leg portions 35 of the platform'member 7 to stop twisting movement `of the platform member lincident tobunipingthe frontend or corners of the platformleg portions' into some'ifured objectfwhen the scale unit/Z is being manipulated on the lift truck 1 or entered under a skid. platform or the like.

One of the important aspects of the present invention "is, the verticalsuspension of a cantilever type or Lshaped weighing platform from a weightv indicating mechanism', which' in turn is suspendedfrom'the upright standard member of the scale. This vertical suspension ywill trans- .mit all vertical load components totheweight indicating mechanism. "Any/turning' moments resulting from applyingthe load-'to'theweighing platform offset with respectto the'vertical suspension are absorbed by the horizontal-parallel `linkagel connections between the weighing platform and the upright-standard.

That is to say,.the upper laterally spaced pair of chainlinks `-connecting theWeighing'A platform and standard member extend'in afcre and :aft-direction,- looki from the-front of 4theplatform toward the yrear-orfuprightl leg -mem-ber thereof, and these chain-links likewise extend fhorizontally/'fand#parallelwith eachother and parallel Awith--the similarlydisposed laterally spacedlower pair -ofhorizontally extending'chaind-inks connected between the platform and standard members.

lThese chains `are structurally speaking, links, and form aparallel yhorizont-allyy extending linkage system` such that any-turning rnomentto which the-weighing platform- -eis subjected, due to the positionpo-f a loader loadcenter -on /t-heplatform, results. ineequal; andcopposingrhorizontal load components through -the upper and lower spaced A.pairs of parallelflrlori'zontlally extending chain-links. These horizontal components Acanceleach other and the load l transmitted tonne weight indicating Imechanism represents "-onlythe-vertical component; of the applied load and thereforexgives: ai truefload-.reading v:1t-the".-weight'-.iindicating .sAnyzfriction':atthe :pivotsjoints of any suchY linkage system,ncanintroduce.an errorinthe reading. in con- 10s'entionalplatform-.leverscales, such: friction is minimized s:byz-.the.provision.of knife-.edges at bearing points. However-knife edgeconstructions. aretoo fragile for practical -use in connection With-theoperation of alift truck.

v .Theelimination of friction at the. pivot joints v.of the L ;describeddinkage.system-canlbe accomplished by providsinggfor .complete exibility.I of thelinksin all planes, .and -byprovidingloosenessat the .link pivot joints. This is L.. achievedin accordance with the embodiment of t-heinven- :.tionadisclosedbythe use of chains for the links, which chainshave-. exibility in,all directions and loose. pivot joints.

v Another, important aspect of the invention related to the parallel, loosely pivoted, flexible linkage system arrangement andnecessary for obtaining errorless readings, 25. is the pro-vision of a weight indicating mechanism having a .suspending member, which actuates the indicator and from Whichtheweighing platform is suspended, that moves only a small distance vertically from no load to full load: condition. In. otherwords, the deflection from no load to full load of the weight indicating mechanism suspending member ...should .be of .the order of a few thonsandths of an inch, ,up to about 0.620. Byfproviding such small deflection f forthe .suspending member, the deviation of the link end pivot joints from the horizontal when a load is applied to the weighing platform is so small, as compared to the tlengths of the links, that vertical components possibly present at the link pivot joints are negligible. The amount of deviation of the link support points during weighing 40. may affect. theaccuracy ofthe scale system; and if there is a largedeflectionof the suspending member, the deviation of the rlink support points from the horizontal would .be large, and would. introduce vertical components at the link pivot points, resulting in substantial error in the Weight indicating readings.

fThus, as a load is picked up and supported bythe weigh- Qing platform, therel is relatively small downward travel ofthe vweighing'(platform with respect to the upright standard because of the slight deflection of the suspending member. vWhen a lift truck is operated and a load picked up,"the entire scale mechanism may be shaken do-wn, soto speak, by truck or fork carriage movement, and the scalemechanism parts assume aV static position. Any vertical components due to friction between the chain links andthe pivot connections at the ends of the links are so small as'to be negligible.

Moreover, ifthe scale or truck is used for instance .in kconnection .with foundry operations where grit, sand, 4dust or `other foreign material may be present and can collect on the parts of the scale mechanism, such foreign 50 material is loosened from and drops from the link pivot joints during the shake down of the scale mechanism, because of the looseness of the joints. Thus, 'the improved construction'eliminates the development of friction at the .linkagepivot points from foreign material.

Although. spaced .Upper and lower pairs of horizontal parallel chain-link-.means are illustrated in the embodiment of the invention shown in the drawings, thev result .accomplished by the same may also be obtained by the 70 substitution of a ,single chain-link-means for either .the

. upper,..or the lower, onboththe upper and lower pairs of ,-cha in,-link .-means;z namely, the equalization or cancelling ,ofopposed horizontal vloadcomponents transmitted to ...'.the links fronts turning Y,moment dueto. offset positioning 'llisofitheiload ongtheweighing platform. If lonechain-linkmeans is used in place of two at either location, th same should be centrally located and all chain-link-means provided rnust be parallel and substantially horizontal. However, it is preferred to use spaced upper and lower pairs of parallel chain-link-means in order to provide a more rugged and stable construction.

Although the fore and aft upper `and lower pairs of spaced parallel chain-link-means have been illustrated and described as being located horizontal, and although such horizontal location is preferred, these chain-linkmeans need not necessarily be horizontal as long as they are parallel.

Since the described upper and lower chain-links that extend fore and aft with respect to the weighing platform, viewing the front thereof, are chains and are exible in all planes, they have no lateral stability. Thus a load placed on the weighing platform laterally to one side or the other of a vertical plane passing centrally from front to rear through the weighing platform will tend to cause a lateral swing of the weighing platform. Such lateral swing or tilting is eliminated by the upper and lower horizontal laterally extending chain-links connected between the weighing platform and the standard member. These lateral chain-links function in a manner similar to the upper and lower pairs of chain-links, herein sometimes termed fore-and-aft extending chain links,

' ing platform and pivoted at its ends through clevis connections with the standard member; while the lower lateral chain-link-means is connected centrally to the standard member and at its ends through clevis connections with the weighing platform. In either instance, the center and end connections of the lateral chain-link-means may be reversed; or separate chain-link connections may extend laterally in each direction at each location rather 'than attaching a center link of a chainto one of lthe members.

Another reason for using a minimum load deflection of the suspending member of the weight indicating mechjanism is that with a long travel for such member, the

lateral chain-link connections between 4the weighing platvform and standard will tend to tighten the laterally ex* tending portions thereof in both directions, which might result in the transmission of improper vertical load components to the weight indicating mechanism. i

Accordingly, another important aspect of the present invention is that the lateral chain-link connections are loose enough that no vertical components are transmitted through the same throughout the deflection or movevment of the weight indicating mechanism suspending member. This looseness condition is not present with respect to the .fore and aft extending chainalink-means when the device is in no load condition, because of the cantilever character of the weighing platform. Thus, the

' tare weight of the weighing platform, the load center of which is offset from the point of suspension thereof from the weight indicating mechanism, constantly subjects the platform to a turning moment. This turning moment is resisted by the tightening of the upper and lower fore and aft extending chain-links which establish the static location of the weighing platform with respect to the lstandard, and as suspended by the Weight indicating mechanism.

Because of this condition, it is preferred in the original assembly of the improved scale mechanism, that the upright leg of the weighing platform be located as nearly `at a minimum distance from the fork carriage.

- 10 in vertical positionas possible, with the uppei end lower fore and aft extending chain-link-means parallel and as nearly horizontally extending as is possible. This matter can be readily taken care of by the adjusting means provided for the fore and aft chain-link-means.

It is desirable from another standpoint that the upright leg of the weighing platform extend vertically upward rather than being angled, `as assembled. If the upright leg extends vertically rather than at an angle, it may be located at a minimum distance from the fork carriage when the scale mechanism is picked up by a lift truck. By keeping such distance a minimum, the load center of the load being handled may be located The further that the load center is from the front of the front lift truck wheels, the greater is the possibility of turning the truck over forwardly on its nose by an attempt to pick up an overload.

Another important aspect of the invention is that the suspension of the weight indicating mechanism from the upright standard member, and the suspension of the weighing platform from the Weight indicating mechanism should comprise pivotjoints loose in every direction, in the same manner that similar loose pivot joints are provided for each chain-link pivot. In every instance, the degree of looseness should be such that foreign matter will shake or drop out of the pivot connections when the load is shaken down for weighing.

Another desirable aspect of the present invention is that all chain-link members operate as tension members when under load, rather than as compression members, which minimizes the possibility of trouble or errors due to friction. Thus, if these link means were compression rather than tension members, no matter how much care may be exercised in providing anti-friction joints for the pivot points thereof, Brinnelling of the relatively rotatable pivot joint surfaces under compression can occur during use which may result in increased friction at the joints causing friction-originated vertical components to be transmitted to the weight indicating mechanism and giving an inaccurate load reading.

Accordingly, the present invention provides a new scale mechanism for accurately weighing a load applied at any offset position on the platform of a cantilever type scale platform suspended from one side thereof; provides a weighing mechanism of the character indicated which is actuated only by vertical load components; provides a new vertical suspension scale construction; provides a mechanism which may be utilized as a part of a portable scale with a lift truck either as a part of or as an accessory for the lift truck; provides a lift truck scale mechanism from which a weight reading can be obtained at any time that a load is carried by the lift mechanism of the truck; provides an improved scale mechanism construction in which the scale platform or table may be con-l structed to have a minimum height or thickness; provides a scale mechanism in which knife'edge mounted lever suspensions or pivot points are eliminated; pro- 60' vides a scale construction which is very rugged in construction and can be operated under all kinds of conditions and subjected to severe abuse without causing any damage to the mechanism or inaccuracies in weight readings; provides a scale mechanism which does not require substantial or constant maintenance or repair to insure accurate weight readings; provides a construction including parallel and substantially horizontal reacting means between the scale standard and weighing platform to absorb in a substantially frictionless manner horizontal components of tilting forces imparted to the Weighing platform by a load applied to the weighing platform offset from the suspension of the platform from the weight indicating mechanism; provides a new scale construction which may be inexpensively built; provides a scale construction which solves long standing problems inthe art,.eliminates the. difficulties ,stated andwhich is accurate infjuse 'and'jobtainsY the foregoing advantages-and defsiderataifin asimple and effectivejmanner. j """Inthe foregoing description, certain terms have been vused for'brevity, clearness land understanding; butl no lower llaterallyextending chain-link having a central link fxed-centrally to said standard membereand 'having-its s ends yconnected/to the-platformleg"portions'wbypivot unnecessary limitations are to be implied therefrom` bei binations, subcornbinations, parts, elements,V arrange-I 2:' ments, discoveries and principles, and mechanical equilva- 1.-.lentsv obvious tothose skilled inthe art. are set forth7 in fthe :appended claims.

Weclaim:

e le Portable ascalev mechanism adapted .to be. usedv as 1an attachment for a forklift truck including yan L-shaped :upright standard member, thestandard member `.includ- ;;in'g.fan.upright leg .and a base leg, there being Outrigger fork engaging means projecting..laterallyfrom, the v.top

4 entrallyfrom-,tbe upperendof theuprightleg, ant.- ,tshapedgcantileyer type weighing-platform member lcentrallyI suspended from said weight indicatingY mechanism, lsaid platform member having laterally. spaced upright ,leg portions laterally adjacent said upright leg` and hav- Ling ,laterally spaced .horizontal `fork-like weight lreceivi ngf-l,eg portions above said fork engagingmeansgspaced parallel upper horizontally; reacting chain-links l con- ,nected between the upper `end .of the standard upright llegandthe upper. endsof the platformfupright leg. portions by. pivot. joints, Aspaced parallel lower horizontally reacting. chain-links connected betweenthe baseleg and weightreceiving leg portions by. pivot joints, an. upper K.laterally:extending .chain-.link having a central link .fixed centrallyto the upper endofthe platform.l memberand @having/.its .ends Vconnected A.with the. upperA end .of-said' upright leg by pivot joints, a lower laterally .extending Y in-linkhaving avv central linlcxedcentrally vto..said Qlbaseleg .and having its ends. connected tothe platform ,legfportions by. pivot joints, said lower parallel kchainnlinks andsaid lower` laterally extending chain-link being located in theV vspace between .said .laterally spaced kplat- A-form:legfportioua and each of said pivot .joints being lose.andruniversally flexible.

2..I`heconstruction defined. in claim l.in.which. adjustable. means isvprovided for. certainL pivot joints of ,saidnpper and lower parallel chain-linkV means.

3.C Scale mechanism. including an v upright. standard `member, a weight indicating` mechanism suspended centr'allyfrom the upper end of the standard member, van

.L-.shapedfcantilever type weighing platformmember cen- ,.,trally suspended from said weight indicatingmechanism, ,said .platform member having laterally spaced` upright legportionslaterally adjacent said standard member and ,having laterallyspaced horizontal .fork-like, weightfvre- ,.ceiving leg portions, .spaced parallel upper vhorizontally f reacting chain-links connected between the upper end of they standard member and the upper. ends of the platform vupright leg portions by pivot joints,k spaced parallel lower horizontally reacting chain-links connected between the "standard memberv and weight receiving legportions by pivot joints; an upper ylaterally extending c hain-link Vhav- A'ing a central link fixed centrally'to -theupper end" of the 'platform member'jand Ahaving its vendsn connected-u with *Tthecupper endbffsaid standardmemberlbypivotgjoints;v a

figthe base leg, a weight indicating mechanismsuspended- Ajoints, -said lower" parallel chain-links andfsaidlower laterally extending chain-link being locatedin-'t-he v"space between said laterally spaced platform vlegportions; `-and each of said pivotfjointsbeing loose and-.universally flexible.

42'Fork lift truck scale mechanism including a lift mast, a fork carriagel vertically-'movable on the mast,

- ari-upright standard member carried by the Icarriage,I` a

weight-indicating mechanism. mounted on thel standard member, an L.shaped cantilever type weighingplatform member having an upright leg and a horizontallyextend- .ing weight receiving leg, means universally flexibly pivotally vertically.suspendingthe platform member from the weight-indicating mechanism, horizontally reacting means engaging between the platform. and standard members holding said platform member suspended.. in .such manner that only actual vertical components of a load: applied to the platformn'iember are transmittedvk to.1the vweight-indicating mechanism. toY register van-v accurate weight indication thereon, vsaid .f reacting means v.beinglexible in substantially .all directions other tharrintension including atleast limited twisting, .and at leastcertain ofi-said reacting means engaging between Vtheplatform member weight receiving legY and .the standard member and extending totally forwardlyof said platformniember upright leg for providing'maximum stability .between so,

the platformand standard members.

5. Scale. mechanism includingk an` upright -standard member,v a weight-indicating mechanism suspended. from `*theVfupper end of said standard member, an L-shaped platform member having an upright leg and a vhorizontally member, afiweightindicating-mechanism suspended from Y extending weight receiving leg; spaced, parallel, upper and., lower, Yfore and aft extending horizontally reacting, cham-link, tension means connected between the platform `and standard members substantially frictionlessly absorbing horizontal load componentsV imparted -toithe platform member -by a .load applied at any offset position .on/the ceiving leg andthe standard member and extending totally forward-ly of the platform member upright legl forvproviding maximum stabil-ity between said standard member and platform member.

v6. Scale mechanism including an upright standard member, a weight-indicating mechanism suspended.-from the upper end rof said standard member,a`n Lv-shap'ed cantilever type weighing platform Amembersuspeild'ed from said weight-indicating mechanism, saidpl'atform member having an upright leg and a horizontally-extending weight Vreceiving leg, spaced upper and lower pairs of fore and aft extending parallel substantially horizontal chain-links connected ,between the platform andstandaid members, spaced upperwand lower laterally extending chain-linksA connected between the platform' and standard members, said chain-links" being flexibleinsubstantially all directions other Jthan `in tension dincludingy at 'least limited twisting, atleast certain ofsaid fore and aft", and at least certain' ofsaid laterally extending chain-links being' connected betweenV the platform member weight receiving leg and the standard member and'extending totally forwardly of the platform member upright lleg, and said chain-links substantially frictionlesslyV absorbing horizontal loa-d components imparted tothe platform member by a load applied atl any offset position "on Vthe `horizontal leg of the platform member. l

l`7.. Scale f mechanism #including :an Aupright-standard the upper end of said standard member, an L-shaped cantilever type weighing platform member suspended from said weight indicating mechanism and having a horizontal leg, spaced parallel upper and lower horizontally reacting chain-link means connected between the platform and standard members, spaced upper and lower laterally reacting flexible means connected between the platform and standard members for resisting substantially all lateral movement of the platform member on the standard member while being substantially frictionlessly flexible with respect to lim-ited vertical movement therebetween, said chain-link means and flexible means substantially frictionlessly absorbing horizontal load components imparted to the platform member by a load applied at any offset position on the horizontal leg of the platform member, and said chain-link means and flexible means being ilexible in substantially all directions other than in tension including at least limited twisting.

8. Scale mechanism including an upright standard member, a weight indicating mechanism suspended from the upper end of said standard member, an L-shaped cantilever' type weighing platform member extending from said weight indicating mechanism and having a horizontal leg, spaced parallel and lower horizontally reacting tension link means connected between the platform and standard members, spaced upper and lower laterally reacting llexible means connected between the platform and standard members for resisting substantially all lateral movement of the platform member on the standard member while being substantially frictionlessly flexible with respect to limited vertical movement therebetween, said tension link means and flexible means substantially frictionlessly absorbing horizontal load components imparted to the platform member by a load applied at any offset position on the horizontal leg of the platform member, and said tension link means and flexible means being flexible in substantially all directions other than in tension including at least limited twisting.

9. Scale mechanism including an upright standard member, a weight indicating mechanism suspended from the upper end of said standard member, an L-shaped cantilever type weighing platform member suspended from said weight indicating mechanism and having a horizontal leg; spaced, parallel, upper and lower, fore and aft extending, horizontally reacting, chain-link, tension means connected between lthe platform and standard members; spaced upper and lower laterally reacting flexible means connected between the platform and standard members for resisting substantially all lateral movement of the platform member on the standard member while being substantially frictionlessly flexible with respect to limited vertical movement therebetween, said chain-link tension means and flexible means substantially frictionlessly absorbing horizontal load components imparted to the platform member by a load applied at any offset position on the horizontal leg of the platform member, and said chain-link tension means and flexible means being flexible in substantially all directions other than in tension including at least limited twisting.

10. Scale mechanism including an upright standard member, a weight indicating mechanism suspended from the upper end of said standard member, an L-shaped cantilever type weighing platform member suspended from said weight indicating mechanism and having a horizontal leg, spaced parallel upper and lower horizontally reacting chain-link means connected between the platform and standard members, spaced upper and lower laterally extending chain-link means connected between the platform and standard members, said horizontally reacting and laterally extending chain-link means being flexible in substantially all directions other than in tension including at least limited twisting, and said horizontally reacting and laterally extending chain-link means substantially frictionlessly absorbing horizontal load components imparted to the platform member bya load applied at any offset position on the horizontal leg of the platform member.

ll. Scale mechanism including an upright standard member, a weight indicating mechanism suspended from the upper end of said standard member, an L-shaped cantilever type weighing platform member suspended from said weight indicating mechanism and having a horizontal leg, spaced upper and lower pairs of fore and aft extending parallel substantially horizontal chain-links connected between the platform and standard members, spaced upper and lower laterally extending chain-links connected between the platform and standard members, said chain-links being exible in substantially all directions other than in tension including at least limited twisting, and said chain-links substantially frictionlessly absorbing horizontal load components imparted t0 the platform member by a load applied at any offset position on the horizontal leg of the platform member.

l2. Scale mechanism including an upright standard member, a weight indicating mechanism suspended from the upper end of said standard member, an L-shaped cantilever type weighing platform member suspended from said weight indicating mechanism, said platform member having an upright leg and a horizontally extending weight receiving leg, said upright leg being generally saddle-shaped in cross-section and laterally straddling said upright standard member, spaced parallel upper and lower horizontally reacting means engaged between the platform and standard members substantially frictionlessly absorbing horizontal load components imparted to the platform member by a load applied at any offset position on the weight receiving leg of the platform member, and said reacting means being flexible in substantially all directions other than in tension including at least limited twisting.

References Cited in the tile of this patent UNITED STATES PATENTS 252,070 Boyle Jan. 10, 1882 722,374 Miller Mar. 10, 1903 884,459 Bricker Apr. 14, 1908 972,443 Forschner Oct. 11, 1910 1,628,179 Nelson May 10, 1927 1,861,443 Holzapfel June 7, 1932 1,887,169 Ross Nov. 8, 1932 2,054,447 Ross Sept. 15, 1936 2,565,792 Wagner et al. Aug. 28, 1951 2,678,207 Wheeler May 1l, 1954 2,720,377 Kerler Oct. 11, 1955 FOREIGN PATENTS 12,697 Great Britain 1906 529,549 Germany July 24, 1931 650,375 Great Britain Feb. 21, 1951

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