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Show pEEBTIlS 81! I HI OFCLUTCH i- S This Vital Unit Requires -U Careful Adjustments and Frequent Inspection. Function and Mechanical ijj Construction of Predomi-.3 Predomi-.3 nating Types Explained. M. Outside the steering mechanism and SB) the brakes there is no other 'dividual unit in the motor car quite S'io vital to the efficient operation, by ? which I mean the actual driving, of the :k motor car, as the clutch. The clutch 3 that is properly taken care of and ad-13 ad-13 justed, performs its functions in such a way that its very existence is almost forgotten. But let the part get out of gear, the facing fail, the bearings wear 43 and the results are instantaneous and 51 unpleasant. An ailing clutch is one of H the most prodigious wasters of power fc-il and reducers of efficiency that can be jjm imagined. In fact, a badly disorgan-NS disorgan-NS ized clutch can reduce the whole niech--io anism of the car to impotency. The clutch occupies a peculiarly stra-I stra-I tegic position in tho mechanism, It- is "HS the coDnectiug link between the engine $ and the transmission, acting as a ilcx- f ible connection whereby the power may - i he applied to or removed from the rear wheels. The operating function of the p clutch is controlled by a pedal, and the 'j part must be employed each time 1 a change of gear is necessary. Obviously ;,M the clutch is a fairly busy bit of meeti-9 meeti-9 anism. Modern clutches fall readily intoi 3 three distinct types; known respectively as cone, disc and plate clutches. Cone and disc clutches are divided into two & subtypes, according to whether they run -rS oil or dry. J Various Kinds. . .Not very long ago cone clutches were rln almost universal on American cars, but 3 within the past few years there has ; 9 licen a notable change in this respect, .. and at the present time disc clutches :a9 are in the majority, with cone in second . j8 place. As the name implies, the cc.n,e M (dutch embodies a cone ns the driven member. This cone fits into the fiy-' fiy-' wheel, which has been hollowed out to recejK it, the engagement being as-Enij("Du as-Enij("Du by a spring fitted for that pur-, pur-, jPose. The surface of the clutch is iphci faced with leather or with a fabric . 0j composed principally of asbestos to reduce re-duce the danger of burning or charring. ;en Rtessure on the control pedal releases TsVvlutch from engagement with the e . flywftoe!, and the power is at once re-. re-. moved from the driving mechanism. When the foot is removed from the pedal the cone is pressed home, the surface sur-face grips the inside of the cavity in the flywheel and the power is trans-ocjf-1 mitfed to the rear wheels. Simple v Enough and efficient in action as long ',...... as the part is properly maintained. ' In the so-called multiple disc clutch, velsthe part is fitted with a number of small discs, sometimes more than fifty L " being used. The inside of the flywheel 3 is fitted with a drum on the inner sur-;'sf;;;i sur-;'sf;;;i face of which are arranged keys de-ogned de-ogned to maintain the discs in a fixed position with regard to each other. The lie tf discs attached to the flywheel act as ;-; driving discs, and the driven discs "'.I Which fit in between are attached to the clutch shaft itself. As the clutch is released tho discs separate and the . :4powor is removed from the driving mechanism. Wheu tho clutch is pressed - - into engagement the discs come to- leihcr and the power is sent bach through the transmission to the rear , ., Wheels. : The Plate Clutch. Finally there is the plate clutch, y'; Which is really only a variation of tho :'.:r.f'-- disc type, lustoad of using a number of small discs this type employs three ' large platos, of which two are the isrg d'iven plates and one is tho driving j-js P'a'e,' fixed on the flywheel. The (burs' Tls,tes may be of metal or they may , iJ have a fabric facing. Within t.no last A or two the plate clutch has mado '"- considerable strides into popularity, and a5 ' there seems to be a bright future for il tliis type. xtfd And now to examine in detail the ;e ft ailments to which the different types he O'i of clutches are heir and suggest tho jon;j remedies to be used for each. The cone ul;3l8i ajntch , consists primarily of the cone, ' the shaft and suitable bearings. In addi-tion, addi-tion, there is a spring, whose function "'- iVi' Pre3s the cone into engagement ll';,(Ttith the flywheel. Tn somo cases in-'Vl in-'Vl of one main spring, three or even ''Imorsnialler springs are used, and in this cse they are mounted at. right au- :'.' files to the eoue. In course of tinre the joi tension of the clutch spring is quite ri;fj Jikely to suffer impairment, so that it ri' 'i no' strength enough to press the r, cone firmly home. In this case the re- - suit is slipping and the cure is adjust-J adjust-J "lent of the spring. (In almost all niod- ?.s ern clutches an adjustment is provided 'or regulating the tension of the spring; V.';-; Usually tho adjustment takes the form .. . of a collar behind the spring, and it is a simple -matter to change the tension . : by this means. When no means of adjustment ad-justment is provided, it is necessary to " ' fit a shim or even to renew tho spring, hut. in any event, tho spring must be ''..'. kept fit to perform its function or much Power will be wasted through slipping. v Care of Bearings. The clutch shaft usually rests upon til- o bearings, generally of the ball tvpe, 3 i'1 "Re located in the center of the 'fly- wheel and the other placed to take lip ',.:;' 'nrust that, results wheu the clutch is it re'?ased. Wear in these bearings is a jjj 'erious matter.. Since on their proper 'ti. on rests tnc functioning of the 0 i ra'ch, any suggestion of wear should ! r, e at once taken up. !D';!ul 5 many eone clutches there is a i H 5end.ency to "grab," that is, to engage l l ' instead of smoothly as is in-- in-- "UJpr Many makers fit a series of ''J'gs either' in the flywheel or under I Je leather facing of the cone, so that I ."agement takes place more gradually. I ' cases whore grabbing is habitual re-I re-I te,t'11R thc leather or fabric facing. Ky'ng it over night in neat's foot oil I wj then running it through a clothes SW will often servo to soften the leather and make gradual engagement possible. On the other hand, when the facing of the cone clutch becomes too heavily oil soaked, it tends to slip and the result re-sult is a heavy loss of power. The cutb in this case is simply to sprinkle a light layer of fuller's earth over the surface, and this serves to soak up the excess oil. Incidentally, when treating the facing of the clutch the flywheel surface sur-face should also be cleaned off. Lubrication of the clutch is one of tho most important things to be remembered. remem-bered. The bearings at the throwout collar and the thrust bearing on tho shaft must be given plenty of proper lubricant. Generally oil or grease cups are provided for this purpose, and these must be filled or turned down at regular regu-lar intervals; one neglect may cause serious trouble. Adjusting Hints. All the suggestions made for caring for cone clutches apply equally to disc and plate clutches, except, of course, those for caring for the leather facing. The springs must be kept up to the mark, the bearings must be regularly lubricated. Tn the case of disc clutches running in oil. there will sometimes be trouble in finding .iust the right lubricant. lubri-cant. Too heavy au oil will cause spinning. spin-ning. If the oil disc clutch is permitted to run dry the plate may burn up. If the oil used is too thin, it tends to pro duce grabbing. The owner will have to experiment with a mixture of oil and kerosene until he gets the right proportions, propor-tions, and even then ho will find that in winter he will have to make the mixture mix-ture thinner than in summer. Some of the oil disc clutches have cork inserts in the discs. When these wear down so that renewal is necessary, this is a iob for the service station, as the cork pieces must be pressed into place by means of a special machine. In most disc clutches an adjustment is provided for compensating for wear of the discs. By adjusting the spring more pressure is added, making up for wear in the plates. In the plate clutch a simple set screw adjustment usually is used for this , purpose. In the dry disc type "slipping may usuallv be cured by flushing the part "out with kerosene to remove the deposits of oily matter and gum that are causing the trouble. However, a great deal of all clutch trouble as relates to' slipping, the commonest com-monest ill of all. is the fault of the driver, who keeps his foot oressing just slightlv on the clutch pedal, but enough to cause slipping. This tends to wear the facing or the discs, as the case may be, so that the effects are cumulative. Therefore, we may paraphrase the familiar fa-miliar saying to make it "watch your foot" |
