US1405597A - Valve-operating device for internal-combustion engines - Google Patents

Description

J. B. KIRBY. VALVE OPERATING DEVICE FOR INTERNAL COMBUSTION ENGINES. APPLICATION- FILED APR.!2,1919.

1,405,597. Patented Feb. 7, 1922,

JAMES B. KIRBY, OF CLEVELAND, OHIO.

VALVE-OPERATING DEVICE FUR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented Feb. 7,. 1922.

Application filed April 12, 1919, Serial No. 289,616.

To all whom it may concern Be it known that'I, JAM'ns B. IIIRBY, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and, useful Improvement in Valvc-Operating Devices for Internal-Combustion Engines,-of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

Thisv invention relates, to internal combustion engines such as are used on automobiles, tractors, and like devices and has for its general object theprovisionof means for increasing the efficiency of the valve operating devices without rendering the same noisy, or, conversely, of reducing the noise of the engine without detracting from its efficiency.

In expensive makes of automobiles, and in some other installations, greatpains and expense are incurred in order to obtain a silent motor combined with an eflicient operation, and whilethe poppet valve type is preferred upon the score of eiiiciency, simplicity, manufacturing expense, longevity, and ease of repair, it has hitherto been found impossible to avoida certain amount of noise and some makers have even departed from this type of motor for that reason. The noise of a properly designed and mufiled engine is almost entirely due to the play or l'ooseness necessarily left between the lift-rod and the valve stem, regardless whether these parts engage directly as in the L-head or T-head engine or through the a ency of a rocker arm as in the I-head motor; for unless a certain minimum degree oflost-motion be permitted, the valves Jill not close completely, particularly when the partsbecome heated, and the slightest excessive 'looseness produces a highly audible hammering. An acceptable compromise between the considerations of' noiselessness and efiiciency is the basis which is com-- monly sought, and salesmenengaged in demonstrating expensive cars frequently make apractice of adjusting the valve tappets' every day with the most extreme care so as to secure noiselessness, notwithstanding; that a slightly increased'f clearance produces a marked augmentation of power.

The object of this invention is the provision of a simple and compact device to be interposed at some point in the operatingv mechanism which shall permit the desired lost-motion without the loss of contact between mctal surfaces and thus wholly eliminate any noise at this point; and the essence of the invention resides in the employment of a link-connection or toggle-joint between the members, and arranged in such wise as to lift or displace the valve when straightened and to take up the back-lash when. defiected."

In the drawings accompanying and forming a part of this application, I. have illustrated several embodiments of my said invention, although it will be understood that these constitute only a small number of the many mechanical forms in which my inventive idea can be embodied. In these drawings, Fig. 1 illustrates my improvements as applied to a typical valve-in-head motor; Fig. 2 is a longitudinal sectional view of the connecting device; Fig. 3 is a similar sectional view of a modified form of the device; Fig. 4 is front elevation of the device shown in Fig. 3; Fig. 5 illustrates my improvements as incorporated directly in the rocker ofa valve-in-head motor; Fig. 6 is a top plan view of the rocker shown in Fig. 5; Fig. 7 illustrates one mode of applying my improvements to an L-head motor; and Fig. 8 is a detail sectional view taken on the line 88 of Fig. 7 and lookin in the direction of the arrows.

Fescribing'first the parts shown in Figs. 1 and 2: 1 represents the cylinder head, 2 the valve stem, 3 the valve spring, 4 the rocker bracket, 5 the rocker, and 6 the lift rod. The rocker 5 is shown as having at one end a shoe 8 engaging the valve stem and at the opposite end a threaded socket 9 in line with the lift-rod and adapted for the reception of adjusting means whereby the lost-motion is regulated. Sometimes the rocker arm is reversed in position, the adjustment being located in line with the valve stem, but the present arrangement is fre quently employedv and will illustrate sufficiently my invention which can be applied to either end of the rocker.

In the socket 9 I secure rigidly a longitudinally bored sleeve 10 having therein a ,slidable plunger 11 whose lower end makes close contact with the lift rod (or valve stem as the case may be). The upper end of the sleeve has a head 12 formed at one side with cars 13, between which is pivoted a link 14; while the plunger 11 is provided with a head 15 formed with an over-hanging bracket 16 located directly above the ears 13 and having pivoted thereto the links 17, the free ends of which are pivoted at 18 to the first link so as to form therewith a toggle joint. The head .15 is formed with a socket 19 substantially in line with the pivot 18 and receiving a spring 20 which bears against'the toggle joint so as tend to deflect the same. Upon each upward movement of the lift-rod 6 thistoggle is straightened against the influence of the spring 20 and the rocker arm is then displaced, while upon the return of the lift rod the deflect-ion of the toggle joint maintains all the parts in tension and prevents hammering. The parts are adjusted by turning the sleeve 10 so that total lost-motion of from 10/1000 to 20/1000 of an inch is permitted which is several times as great as is permissible with the plain tappet, and the permissible tolerance in the adjustment is so great that itcan be effected with a minimum of skill or experience.

In the construction shown in Figs. 3 and 4:, the sleeve 10 is formed at its upper end with a head 12 having the spaced arms 13" between which is located the head '15 of the plunger 11, the last named head having the bifurcated brackets 1616. Tothe cars 13 are pivoted the links Pi -14? and to the bracket 16 there is pivoted the link 17" whose free end is pivoted at 18 to the first named links. The link 17 is formed with the socket- 19 in which is received the spring 2-0 whose purpose is to deflect the links out of a straight line. The operation of the device is the same as before.

In the embodiment shown in Figs. 5 and 6 the rocker is formed in two parts 30 and 31 respectively, whose meeting portions are branched so as to be pivoted upon a spindle 32, the ends of the branches being turned 'upwardlylto form the ears 33and 8 1 respectively. inks 85 and 36 are pivoted to gether and to these ears so as to constitute a toggle'joint, and a spring 37 (here shown as a compression spring) is employed to break the toggle.

In the embodiment shown in Figs. 7 and 8 the valve stem 2 and lift-rod 6 are arranged in line with each other. To the end oft-he valve rod is applied a socket member 40 having lateral ears 4:14c1 to which are pivoted the links 42-42 while to the end of the lift rod there is applied'a socket member 413 traversed by a pivot 44:

' to which are pivoted the links 45-45 whose free ends are pivoted at 46 to the free ends of the first links. I have here shown a spiral spring 47 wrapped around the pin 44 myself to the constructions herein shown ex cept as described in my claims and rendered 7 V I necessary by theprior art.

Having thus described m invention what I claim is 1. In an internal combustion engine of the poppet valve type,'the combination with a valve-stem and its lifting rod, of connecting means interposed therebetween and comprising a series of links pivoted together and at their ends, and spring means tending to defiect said links laterally, said links being arranged to open the valve by a'pulling action when the lift-rod is raised.

2. In an internal combustion engine of the poppet valve type, the combination with a valve-stem and its lifting rod, of a movable member abutting against one of those parts, a link pivoted thereto, a second member abutting againstthe other part, asecond link pivoted to the first link and to said second member, and spring means tending to de fiect said links out of a straight line whereby said members are held snugly against the parts which they respectively abut,

rocker and abutting againstithe other of" those parts and a pair of links pivoted together and to said rocker and member, re-

spectively, and a spring tending to move 7 said links laterally, said links being ar-C ranged to come into tension as said rocker is moved. i j V 4. In an internal combustion engine of the with a valve-stem and its lift-rod, ofa rocker abutting against one of those parts, a pivot carried thereby, a relatively movable member carried by said rocker and abutting against the other of those parts, said member exv1G5 poppet-valve-in-he'ad type, the combination tending past said pivot and itself having a pivot located upon the opposite side of said firstpivot from the part which said movable mem together and attached one to each of said pivots.

In testimony whereof, I hereunto aflixmy signature. 7 JAMES B. KI-RBY;

er abuts, and a pair of links pivoted

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