US1591705A - Actuating device and method of making the same - Google Patents

Description

July 6, 1926: 1,591,105

' E. J. GUAY ACTUATING' DEVICE AND METHOD OF MAKING THE SAME Filed Feb. 6' 1924 EMA e2 UT Quay v zlsf fia may.

Patented July 6, 1926.

UNITED STATES PATENT OFFICE.

EMILE J. G'UAY, OF SWAMISCOTT, MASSACHUSETTS, ASSIGNOR TO GENERAL ELEC- TRIO COMPANY, A CORPORATION OF NEW YORK.

Application filed February 6, 1924. Serial No. 691,077.

In my Reissue Patent No. 15,805 issued April 1, 1924:, I have disclosed and claimed a means for reducing the noise and shock between two contacting elements, one of which actuates the other, as for example, a valve and a valve lifter in an internal combustion engine.

The present invention relates to the same general subject matter and has for its ob jects to simplify and reduce the cost of manufacture of such means or devices; to improve the product by increasing the density of the shock absorbing body to the end that it shall have a longer life, and to reduce the number of parts.

For a consideration of what I believe to be novel and my invention, attention is directed to the accompanying description and the claims appended thereto.

In the attached drawing, which is illus trative of my invention, Fig. 1 is a diagram mat-ic view of a treating tank; Fig. 2 is a plan View of a sheet of highly compressed material composed of spinnable textile fibers and a binder; Fig. 3 is a perspective view of one of the rods from which the actuating devices are made; Fig. 4: is a sectional view of a die; Fig. 5 is a sectional view of an actuating device, in this case a tappet screw; Fig. 6 is a diagrammatic View of an engine valve and its lifting or actuating mechanism, and Fig. 7 is a sectional view illustrating a modified form of securing means for the textile material.

In carrying out my invention I take spinnable textile fibers, as for example cotton, and to attain the best results form them into a body of considerable surface area in which the fibers are arranged side-by-side and extend lengthwise, avoiding as far as may be reasonably possible the presence of cross fibers. Cotton batting is suitable for the purpose when specially carded so as to dispose the fibers longitudinally.

The batting as indicated at 7 is passed through a tank 8 containing a binder 9 such as for example bakelite, shellac or the equivalent, there being suitable rollers for guiding and directing the material in its passage. By preference the binder is relatively thln and has a low specific gravity whereby the fibers are lightly coated. On issuing from the tank the material passes through a pair of wringer rolls 10 which squeeze out a large percentage of the binder. My experience has demonstrated that the amount of binder left in the material should, to attain the best results, be the least amount that will permit of handling of the same in the subsequent operations. The principal reason for this is that the binder does not possess the same elasticity as the fibers and if present in substantial amount in the finished product, tends to crumble or disintegrate due to the hammer-like action of one part on the other when in service. As an example I find that when the binder is from 15 to 20 per cent of the total weight of the material that the results are satisfactory. After being treated in the tank the material is then dried in any suitable manner which removes the solvent. The number of treated sheets of batting necessary to produce the final sheet 11 is then placed in a press such as a hydraulic press having suitable heating means and subjected to heavy pressure. By way of illustration but not as a limitation, the pressure may be from 8 to 4 tons per square inch of surface of the material although in some cases it may be as low as one ton per square inch. Vhile in the press the sheet is subjected to a suificient amount ofheat to cause the binder to harden or set and hold the fibers of which the sheet is composed under heavy compression. This may be termed the initial compression.

After the sheet is properly formed it is sawed or cut as indicated by the dotted lines 12, Fig. 2, into rectangular rods 13 which are afterwards cut or turned into round rods 14 as shown in Fig. 3 which have a relatively high tensile strength. These rods are then cut into short lengths to form what may be termed plugs or bodies 15 in which the fibers extend lengthwise. First forming the textile material into sheets and then cutting the sheet to form plugs has the very material advantage from a manufacturing standpoint that the plugs so produced will be of practically uniform density because the weight of cotton fibers and the binder used as well as the compression pressure can be accurately determined in advance. Having plugs of uniform density means that the final compression due to the die operation will be uniform. As a result of this the finished prod not can be made uniform, all of which means the avoidance of losses in manufacture.

In Fig. 5 is shown a holder for a plug which in this case takes the form of a tappet adjusting screw having an enlarged head 16 and a threaded shank 17. The lower part of the head is made in the form of a hexagon nut to receive a wrench while the upper part is annular. In the head is a socket 18 having a flat bottom and a cylindrical wall perpendicular thereto. The diameter of the socket is such that a plug 15 when inserted makes a snug fit therein. By making the plug a snug fit two advantages are attained: First, the plug is prevented from dropping out of the screw in the subsequent handling, and second, it ensures uniformity in the product as to the compression pressure of the fibers after the die operation which imparts the final pressure. Before the plug is mounted in the socket the threads of the screws are preferably hardened to reduce wear, thereby deceasing the necessary adjustments when in service to keep the screws in their proper positions. Care should be exercised not to harden the wall of the socket any more than is absolutely necessary, as otherwise the metal will spring back by too great an amount after the die operation and the compression pressure on the cotton fibers will therefore be less than it should for the purpose intended. Having assembled the plug in the socket the next step is to force the die 19 down over the upper part of the head. The bore of the die is slightly smaller than the outside diameter of the head. As an example but not as a limitation of my invention it the diameter of the head is 650 onethousandths of an inch the diameter of the bore in the die is 625 one-thousandths. lVhen the die is forced down over the upper end of the head of the socket it decreases its diameter slightly and at the same time increases the sidewise pressure of the wall of the socket on the plug 15. This may be termed the final compression. In such an operation the wall of the socket will spring back somewhat after the die is removed and this fact must be taken into account in determining the size of the die. In all cases the wall of the socket after the die is ren'ioved. and the spring back takes place should hold the cotton fibre under a compression pressure greater than the initial. As a result the fibres will of course be in firm contact with the surrounding compressing and supporting wall. Under the conditions specified the compression of the cotton or other fibers is increased by approximately 20 per cent at the outer end with the result that it becomes very hard and dense with the ends of the fibers exposed for contact with the cooperating part of the valve or other mechanism, the shock and noise of which is to be decreased. By varying the diameter of the bore of the die for a given diameter of socket, the final compression can be varied at will.

Generally speaking the compression pressure will be determined by the particular force for which the tappet screw is intended to withstand. In other words, the pressure will be determined by the force of blow exerted by one part on the other. As a result of the fact that the die acts chiefly on the upper portion. or end of the socket it follows that said end is slightly smaller in diameter than the lower end which gives to the plug a slight restriction or taper with the larger end at the bottom. This serves to hold the plug in place on its seat without additional securing means. It also follows that the plug is more highly compressed at its outer than a 15s inner end. The advantage of this resides in the fact that hammer blow due to the cooperating part of the valve or other mechanism fall on the part which has the greater compression and hence the wear is correspondingly decreased. After the final compressing operation the top of the plug is machined in such manner that the center is flat and rises slightly above the wall of the metal holder to form a contacting or working surface.

In Fig. 7 is shown a slight modification of the invention. In this case the plug 15 is snugly fitted into the socket and may with advantage be made a driving fit therein. The upper end of the plug has a small annular shoulder 20 thereon and the metallic wall of the socket at its upper end 21 which is relatively thin is deformed in such manner as to engage the shoulder on the plug and hold it in place. One way to effect this deformation is to roll over said edge. In this case as in Fig. 5 the center of the plug is flat and is beveled or crowned from said fiat portion to the outer edge. It is preferable in all cases, if the best results are to be obtained, to make the plug relatively long, so as to have a substantial body of cotton fibers between the cooperating metal parts so as to absorb shock and reduce noise.

In Fig. 6 my invention is shown in conneetion with an internal combustion engine by way of example. 21 indicates a valve of usual construction the stem of which is acted upon by the plug 15 of the tappet adjusting screw, there being a slight clearance between the parts. It is this clearance which is the cause of noisy valve operation when parts made wholly of metal are employed. iVith my improved tappet screws this objection is overcome and the clearance may even be increased over that used with metal screws without detriment. The valve is closed by the spring 22. The tappet screw is actuated by the cam 23 and reciprocating member 21 which works in a suitable guide. The other parts of the engine are not illustrated because they are not necessary to an understanding of the invention.

Tappets constructed in this manner have lli) been subjected to severe tests in automobile engines and with the usual valve adjustment as to clearance and ordinary valve closing springs it has been found that the average wear is approximately one-eighth of onethousandth of an inch for each 1000 car miles, which is substantially less than was obtained with tappet screws made in accordance with the aforesaid patent, the reason being that by the present process it is possible to very substantially increase the pressure on the fibers. The wear is also much less than where there is a metal to metal contact as in ordinary constructions.

By reason of my improved construction the tappet noises are virtually eliminated and the adjustments need not be so close as is generally considered necessary to ensure reasonably quiet operation. The use of larger clearances has the distinct advantage that there is very much less liability of burning' the valves or their seats due to failure of the valves to seat. It will readily be appreciated by those who have occasion to adjust such valves, especially on an automobile engine, that it is a difficult matter to adjust the parts when cold so that the valves will on the one, hand, properly seat when hot and on the other hand, will not give rise to excessive noise and pounding. Another advantage of my improved construction over the well known steel screws having hardened heads and aside from its noiseless properties, is that if the top surface of the plug is worn or injured, it can be resurfaced the simple. operation of filing it and this without removing the same from the engine.

In accordance with the provisions of the patent statutes I have described the principle of operation of my invention, together with the particular method and apparatus which I now consider to represent the best embodiment of my invention, but I desire to have it understood that the particular method and apparatus disclosed is only illustrative and that the invention may be carried out with such modifications as come within the scope of the appended claims.

hat I claim as new and desire to secure by Letters Patent of the United States, is,

1. In a device of the character described, the combination of a head having a socket in one of its ends, and a plug in the socket comprising compressed spinnable textile fibers, the outer end of said plug presenting a working surface and being held by the wall of the socket under greater compression pressure than the inner end.

In a device of the character described, the combination of a head having surfaces adapted to receive an adjusting wrench, said head having a socket in one end which is slightly smaller at its outer end than at its base, an adjusting means connected to the head, and a plug comprising highly compressed spinnable textile material which fills the socket, the fibers of the material being retained in a highly compressed state by the wall of the socket which wall also holds the plug as a whole in place.

3. In a device of the character described, the combination of a head having a socket in one end, and a plug therein comprising longitudinally-extending compressed spinnable textile fibers held under compression by a small percentage of binding material, the outer end of the wall of the socket serving both to increase the compression of the fibers in that region and to hold the plug in place.

4. In a device of the character described, the combination of a metal holder having a socket at one end and a screw-threaded portion at the other end, and a plug in the socket comprising textile fibers and a binder which holds them under compression, the outer end of the plug being exposed to form a relatively hard, dense working surface, and the wall of the socket adjacent to the outer end of the plug being deformed to exert greater pressure on the plug at its outer end than at its inner end.

5. In a device of the character described, the combination of a head having a socket in one end, a filling plug in the socket comprising longitudinally extending fibers united by a binding material that serves to hold them in compression, the outer ends of the fibers in the plug being exposed to form a working surface, and the wall at the outerend of the socket being deformed to hold the plug against axial movement in the socket.

6. The method of manufacturing devices of the character described which comprises forming a short, cylindrical plug of compressed spinnable textile fibers and a binder, inserting the plug thus formed in a socket and exerting sufficient sidewise pressure on the top of the socket to deform the same and cause additional compression of the fibers, the pressure exerted on the plug at the top of the socket being greater than the pressure exerted on the plug at the bottom of the socket.

7 The method of manufacturing tappet devices which comprises forming sheets composed of textile fibers which have been treated with a small amount of binder, subjecting the fibers to heavy pressure and to heat to cause the binder to harden and retain the fibers in compression, cutting the sheets to form rods, cutting the rods to form plugs, inserting a plug in a socket in a metallic holder, and subjecting the wall of the socket to external pressure to reduce the size of the socket at its outer end and increase the compression pressure on the fibers.

In witness whereof, I have hereunto set my hand this fourth day of February, 1924;.

EMILE J. GUAY.

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