Патент USA US2406244код для вставки
Aug. 20, 1946. I H. NUTT` ' FRICTION CLUTCH `Filed. May 24, 1943 /1 / 2,406,244 Patented Aug. 20, 1946 21,406,244 `UNITED STATES PATENTl OFFICE FRICTION CLUTCH Harold Nutt, Chicago, Ill., assigner v,to Borg Warner Corporation, Chicago, Ill., a corpora tion of Illinois Application May 24, 1943, Serial No. 488,163 ’7V Claims. (Cl. 192-99) 1 \ 2 Thisr invention relates to friction clutches of the. type employed in motor vehicles and has as its general object to provide an improved mech threaded end» I5 of the eye bolt, and engaging cover. washer is designed so as to have a zero rate the outer end of the boss 9. The Belleville Washer I2 takesover the func. anismr :for mounting the release levers and con tion of the former hold back spring in main necting them to the pressure plate of a clutch 5 taining the adjusting nut in snug engagement of this type. with the cover member at all times. Thus the A specific object of the invention is to elimF Belleville washer in combination with the snug inate` the necessity for the conventional hold-back fitting characeristics of the pivot pin and strut, spring. A further object of the invention is to eliminates the necessity lfor the hold back spring. ` provide an improved adjustable mounting for The Belleville washer has the further function the lever fulcrum eye bolt. The invention in of providing a substantially constant positioning this respect is particularly applicable to a heavy load on the eye bolt throughout the normal range duty clutch of a type employing a cast metal of adjustment thereof. For this purpose, the f These and other objects and features of this 16 deflection characteristic. invention will become apparent from the follow The Belleville washer I2 is suñiciently stili to ing speciiication when taken together with the resist the axial component of centrifugal force that may be developed in the lever I'I when the weight of the latter is centered rearwardly (to ing the invention. 20 the right as viewed in the drawing) of the pivot As an example of one form in which the in pin I9, as when the lever is in engagedposition vention may be embodied, the drawing shows a after the facings have become worn so that the heavy duty clutch adaptable for use in military packed thickness of the driven vmember as tanks. Such a clutch may embody a cover I semblies is reduced. It will be apparent that of cast metal such as cast steel, suitably con 25 such a centrifugal force, in conjunction with the toggle arrangement of the outer end of the lever nected to a driving member, indicated in broken lines at 2. Twin driven discs 3 and an interven and the head of the eyebclt, woulddevelop a ing, iioating pressure plate 4, likewise indicated component tending to press the eyebolt rear in broken lines, are adapted to be packed in fric wardly and against the Belleville washer I2. tional engagement with each other and with a 30 In conventional lever arrangements of this gen pressure plate 5 and the driving member 2 by eral type it has been customary to provide the pressure transmitted through the lever mecha eye bolt with a tail portion extending through nism forming the subject matter of my invention. the lever and into a recess in the pressure plate My improved lever mechanism embodies a in order to provide adequate support against the lever fulcrum eye bolt 6 having a prism-shaped outward pressure of the lever, acting under cen shank 'I received in a correspondingly shaped trifugal force, against the eye bolt. Because of aperture 8 in a boss 9 formed in the cover I. the close ñt of the shank 'l in the aperture 8 for A shoulder I0 at the base of the head portion a substantial axial distance, this tail portion may be and is eliminated by the present invention. I I of the eye bolt 6 is engaged against the inner The extended ñt of the shank 'I in the aperture portion of a Belleville washer I2 which` in turn 8, in connection with the non-circular cross is engaged at its periphery against the inner sectional shape of these parts, also makes it pos end of the boss 9. Inwardly of the radiusA where sible to utilize the eye bolt as the means for it is engaged with the Belleville Washer spring I2, accompanying drawing which shows an axial sec tional view through a portion of a clutch embody supporting the f lever I1 against displacement the boss 9 is counter-bored to pro-vide an annu lar space I3 into which the inner portion of the 45 about the axis of the eye bolt, the head portion spring I2 may be ñexed if necessary. II being formed with flat sides snugly fitting be tween the wall portionsr f8 of the lever to effect this purpose. Thus the conventional practice of cal shape to the flat washer shape shown in the iitting the side -wall portions of the lever over a drawing and is thus adapted to move a limited 50 part of the pressure plate lug so as to support the extent on either side of the flat plane of its ñat lever against displacement about the axis of the washer shape in order to accommodate the ad eyebclt, is eliminated. justment of the eye bolt 6 toward and from the The head portion II of the eye bolt 6 is pressure plate 5. Such adjustment is effected provided with an eye I6 which is elongated by rotating a nut I 4 threaded on the reduced 55 transversely of the bolt. A release lever I'I, of The spring I2 is pressed from a normally coni i? ' Y 2,406,244 4 ` 3 back-lash between the lever and said yfulcrum n channelled construction having side walls I8 em bracing the head II, is pivoted to the eye bolt element in this direction, whereby the necessity for a hold-back spring is eliminated. 3. In combination with a pair of clutch' mem extending through the eye I6. The pintle I9 has very slight clearance in the eye I6 longitudinally 5 bers, an operating lever having -a portion ful crumed with reference to one of said members of the bolt, thus` eliminating backlash between 4and having a pivot pin, an eye bolt having a. non the lever I1 and theeyebolt in a direction par cylindrical shank'fitted into a correspondingly allel tothe clutch'axis'.V ' ' ‘ ' shaped aperture in the Vother member, said eye _ The outer end of the lever I'I is formed withV a saddle 20 in which is seated one end of a strut 10 bolt having a head in which said pivot pin is ` ' by a pintle I9 mounted in the side walls I8 and 2| the other end of which is seated in a notch 22nl ' lfulcrumed, a Belleville washer interposed be ' tween said head and said other memberwith said in a driving lug 23 formed on the pressure plate 5. The driving lug 23 is received in and adapt-v head engaged against the inner portion of said washer and said other member having a recess deñned within a raised annular fulcrum against edA to have driving engagement with a pocket 26 , formed in the cover I. The saddle 20 and strut 2l are accommodated which the- peripheral portion of said washer is I engaged,.and an adjusting nut threaded on the with only slight clearance in a recess 21 in the driving lug 23, so as to eliminate back-lash be end of said eye bolt opposite said head and en gaging said other member on the side thereof tween the outer end of th'e lever and the pres-` ' sure plate. ' As a result of eliminating back-lash. opposite said Belleville washer. 4. The combination defined in claim 3, where at this point and in the eye I6, it has been `pos sible to eliminate the hold back spring conven ' tionally employed for reducing back-lash in the lever linkage. I claim: Y A in said Belleville washer is stressed to a substan- y tially flat plane and is capable of being stressed into said recess on one side of said plane’or be 25 coming unstressed to a position lying on the f other side of said plane. yl. In combination with a pair of clutch mem-` Y » ` 5. The combination defined in claim> 3, where in said eye bolt head has flat side faces embraced by side wall portions of said lever and thereby ber, said fulcrum element having a non-circular ` region and an eye, a lever having a pivot` pin ful-` 30 'holds said lever against displacement about the ` axis of said eye bolt. crumed _in said eye, and _an end portion project 6. A combination as deñned in claim 3, where ing into said recess, means on said leverisnugly in said end portion of the lever is received'in a> ñtting said non-circular region to maintain'said bers one having a recess, a fulcrum element car-4` ` -ried _by the other member free of the ñrst mem recess in said one member, and including a strut " interposed between one side of said recess and , lever against displacement around said "element, and a strut interposed between said end portion said lever `end portion, the latter being main- v and one side of said recess, said strut maintain tained by said strut in close proximity tothe ` ' ing said end portion in bearing relation with re v other side of said recess so as vto eliminate back-"ji spect to the other» side of said recess so as to eliminate any apDIeciable'back-lash between said end portion and said‘recessed‘clutch member, saidr pivot pin being fitted in said eye with sunl lash in said recess, and said pivot pin being fitted 40 in said eye with no backlash therein, whereby the necessity for a holdback spring is eliminated. ` 7.'A clutch comprising a driving> member; a Y cient snugness transversely of the lever to elim f inate any appreciable back-lash'therein, where clutch'pressure plate coacting therewith having by the necessity for a hold back spring is elimi nated.Y ' ‘ ’ a recess; a Vcover plate carried by said driving . _member; a shouldered fulcrum member adjust ably carried by said cover and having an eye and f a flattened region adjacent said eye; a lever hav 2.I In combination'with a Ãpair of clutch mem- l bers one having a recess defined between opposed I ing apivot pin fulcrumed in said eye andan end surfaces, a fulcrum element carried> by the other portion projecting into said recess, said lever hav member and having a non-circular region' and an eye,`a lever having a pivot pin extended . Ying a channeled portion snugly ñtting the nat tened region of said fulcrum’member for main-V throughrsaid eye and an end portion in the form' taining said lever against displacement around K of avfsaddle having a convex surface in bearing the axis of said fulcrum member; a Belleville type . relation ¿Vith respect to one of saidopposed sur spring washer on said fulcrum member in ten faces,'said lever having side portions fitting said non-circular region thereby preventing sidewise 55 sionedrelation to the shoulder thereon, and a » displacement of said lever, a strut having one end received in said saddle and its other end ful crumed against the `other of said opposed sur-` faces, said strut and saddle together ñlling the space between said opposed surfaces with only slight clearance so as to eliminate any appreciable back-lashrbetween said end portion and said re cessed clutch member, and said eye being elon gated longitudinally of said lever to permit said , pin to ‘have rolling contact therewith and em-` 65 bracing said pin snugly -in a direction transversely of‘ said lever so as to eliminate any appreciable strut interposed between saidend portion of the - lever and a side of said recess, said strut main taining said lever end portion in bearingrela tion with respect to the opposite side of said re cess so as to eliminate any appreciable back-lash ‘ between said end portion and said pressure mem ber, said pivot pin being ñtted in said eye with f suiiicient snugness -tranversel‘y of Vsaid leverv to` eliminate any .appreciable back-lash therein, whereby rthe necessity for ahold-back spring is eliminated. HAROLD Y "