US1841344A - Packing for the rotary valves of internal combustion engines - Google Patents

Description

Jam. 12, I932. A. BAER 1,341,344

PACKING FOR ROTARY VALVES OF INTERNAL COMBUSTION ENGINES Filed Sept. 18, 1928 3 Sheets-Sheet 1 r vav rm? Jan. 12, 1932.

A. BA ER masque FOR THE Ronny VALVES or INTERNAL COMBUSTION, mma's Filed Sept. 18. 1928 3 Sheets- Sheet 2 A. BAER Jan. 12, 1932. v

PACKING FOR THE ROTARY VALVES OF. INTERNAL COMBUSTION ENGINES Filed Sept. 18, 1928 :s Sheets-Sheet s S Mr Q bk u T r ll. l yl n I l l II\I||.||J QM 4 [I4 Q N 5 MN \N. MW N \m w wm I, 4 N i 4%. o \N o .QN. m w 4% NW #4 NI? Q N k %&w\ M

Patented Jan. 12, 1932 UNITED STATES PATENT OFFICE ALFRED BAER, BERLIN, GERMANY PACKING FOR THE ROTARY VALVES OF INTERNAL COMBUSTION ENGINES Application filed September 18, 1928, Serial No.

This invention relates to an improved packing for the rotary valves of internal combustion engines. As is known the chief difficulty in using rotary valves for internal combustion engines lies in the fact that it is impossible owing to the high temperature to which said valves are-exposed when in operation to fit thevalves in such a gas tight manner as is possible in the case of steam engines, particular difliculty existing in designs in which {he 'otary valves are located in the cylinder lea It is necessary that the diameter of the valve whilst cold shall be somewhat smaller than the diameter of the bore or housing in which it is to operate so that in operation the valve can expand when heated and efiect proper operation in this state. Such rotary valves, however, owing to the unfavourable working conditions are subject to very heavy wear and it is found to be impossible to keep even excellently fitted valves gas tight for any length of time. This lack of tightness involves loss of energy and, therefore, the fitting of rotary valves in fixed bores or housings has been practically discontinued, said rotary valves being now fitted in housings comprising two mutually movable halves, which can be so adjusted towards one another by mechanical or automatic means that satisfactory working of the parts can be obtained independent of the effects of temperature orwear.

Unfortunately, the expedient suggested above introduces high working pressures and the friction on the valve becomes great with the result that a comparatively large proportion of theenergy produced is absorbed in operating the valvesand to overcome this difficulty it has been proposed to mount the rotary valve in roller bearings Vith such an arrangement it has been found necessary to make the parts which 00'- operate With the rotary valve movable in said rotary valve.- Such arrangements, as is known, introduce the disadvantage that dlfficulty exists in maintaining a gas tight joint themselves and to fit each part separately'to' 306,640, and in Germany September 19 1927.

at a certain number of revolutions as the speed increases the performance of the engine does not increase in ratio to the number of revolutions but at a much lower rate. This defect is due to the fact that with high speeds of revolution a continually larger percentage of the products of combustion are retained in the cylinder space or in the passages leading thereto owing to ineffective joints and these products of combustion contaminate the incoming fresh gas mixture with the result that the value thereof is reduced.

This invention has particular reference to a packing for rotary valves of the type hereinbefore referred to and avoids the difliculties indicated, thus making it possible to effect, at all times, a roper gas tight joint between a rotary valve aving a fixed bearing and the parts cooperating therewith both at the inlet as well as the exhaust ports.

Further, the improved construction provides that the rotary valve shall require less energyto drive it than has been possible in known arrangements inasmuch as the pres' 7 sure of the cooperating parts with the rotary valve is considerably relieved and the highly objectionable seizing of the cooperating surfaces entirely obviated.

An especial advantage of the invention re- 0 sides in the fact that owing to the satisfactory packing arrangements all loss of fresh gas mixture and, at the same time, any contamination of the same by exhaust products is absolutely avoided.

In the drawings Figure 1 is a sectional elevation'of part of an internal combustion engine;

Figure 2 is a side elevation of the construction illustrated in Figure 1, the view being taken on the line 2-2 of Figure 1;

Figure 3 is a detail sectional view through the lower part of the cylinder head and rotary valve as illustrated in Figure 1 but to an enlarged scale;

Figure 4 is a sectional elevation of the improved rotary valve; Figure 5 is a fragmentary view showmg in side elevation a part of the improved ro- 1w tary valve;

Figure 6 is a plan view of the movable part of the cylinder head;

Figure 7 is a plan view of the flexible packing element for the movable part of the cylinder head;

Figure 8 is a side sectional elevation of Figure 7 taken on the line 8-8 thereof and looking in the direction of the arrow;

Figure 9 is a sectional elevation of one of the upper packing shoes;

Figure 10 is a plan view of the packing illustrated in Figure 9;

- Figure 11 is an end elevation of the packing shoe illustrated in Figure 9 looking in the direction of the arrow and showing in elevation the jointing element;

Figure 12 illustrates in sectional elevation an alternative construction.

As illustrated in the drawings, 1 indicates the cylinder, 2 the piston, 3 the cooling jacket of the cylinder and 4 a cylinder head extending over the whole of the cylinder block, said cylinder head being jointed to the cylinder block by means of the packing plates 5. Botary valves 6, 6 are arranged in bores in the cylinder heads 4, said valves being combined in pairs for each two cylinders and supported inthe ball bearings 7 The contacting parts betweemeach two rotary valve parts 6,

shoe

6' as illustrated in Figure 2 are kept coaxialby aligning rings 7 and are united into a whole by the pins 8. Adequate play is provided between the rotary valves 6, 6 and the corresponding bore of the cylinder head said rotary valvesbeing formed hollow and each having two diametrically opposite openings 9 in thecircumfer'ence and an open ended passage 10 which passes across the valve,

Both the openings 9 and the openings of the passages 10 serve as ports for the inlet of the fresh gas and the discharge of the exhaust gases.

A packing piece 11 is arranged in the lower part of-each cylinder head 4 and opposite the 7 serving to retain the diaphragm 12 in place.

rotary valve 6, 6 as is clearlyshown in Figure 3 said packing piece forming the top cover of the cylinder and having openings 9' and 10' (see Figure 6), which cooperate with the corresponding openings of the rotary valve. The packing piece 11 is movable axially and is retained in position by a. diaphragm 12 (Figures 3, 7 and 8) which may be of nickel and which is initially stressed so that the packlng piece 11 is always pressed against the surface of the valve with a certain pressure.

of a ring of sheet metal, say nickel. having a circular raised bead 12 pressed therefrom, the flange like portions of the ring provided on both sides of the circular raised bead 12 The inside flange is fixed to the packing piece 11' by means of the screwed ring 13, whilst the outer flange is pressed by the screwed ring 14 against an abutment surface in the cylinder head (see Figure 3) so that the packing piece 11 shall be axially movable to the extent of the elasticity of the diaphragm 12, said packing piece 11 being pressed against the rotary valve by the pressure in the cylinder 1 when the pressure in the cylinder produces a force on the piece 11 which exceeds the force exerted by the diaphragm.

Packing Shoes 15 and 15 are arranged in the upper part of the cylinder head 4, opposite the openings 9 and 10 of the rotary valve as illustrated in Figures 1, 9, 10 and 11. Each of these shoes consists of a part 16 which fits to the circumference of the rotary valves andan inlet conduit 17 (see Figure 9) an axially arranged projection or shoulder 18 serving.as a bearing surface for the pressure spring 20 arranged in a special guide 19 in the cylinder head 4. A circular raised or beaded portion 21 is arranged on the free end of the conduit 17 and has a jointing diaphragm 22 similar to the ointing diaphragm 12 pressed thereon'by means of the flange of ceived from the suction piping 23 through the hollow rotary valve 6 into the cylinder 1, the flow of fresh gas into the interior being unobstructed. During the compression and expansion strokes which now follow, the rotary valve 6 turns in the direction of the hands of a watch, so that at the moment when the exhaust stroke begins the passage 10 is in a vertical position and the opening of the passage 10 is opposite the opening 10' (see Figure 6) in the packing piece 11. Owing to the pressure in the cylinderthe packing piece 11 is pressed against the rotary valve 6 so that the exhaust of the products of combustion is effected without leakage it being impossible for any products of combustion to escape laterally. This is ensured, firstly, by the fact that the surface of the packing piece 11 is tightly pressed against the periph- I, secondly by the fact that the products are As will be seen, the diaphragm 12 consist-5f? much pressure is exerted on the packing shoes as is absolutely necessary to prevent any lifting of the packing shoes.

As thei'otary valve'is a loose fit in the bore thereforall unnecessary resistance is avoidcd. During the compression, expansion and exhaust periods the packing piece 11 is pressed against the circumference of the rodescribed eflectively fulfils its purpose in a general way, when operation for lengthy periods is essential difiiculties arise owing tothe effect of the high temperature upon the elasticity of the packing ring, said elasticity being found to somewhat diminish, There is a further difficulty that the oil necessary for lubricating the various operative surfaces exposed to friction is adversely affected by the temperature which exists and which has as its result a reduction in the lubricat ing power of the oil.

The valve is continually "cooled by a flow of cooling medium therethrough, the internal cooling arrangements preventing excessive heating of the parts and, at the same time, serving to conduct as much heat as possible from the cylinder end. Afurther advantage.v

of the alternative arrangement is illustrated in Fig. 12 which presents the additional advantage that by means of a supplemental packing arrangement the actual packing is excluded from the intensest heat in the, combustion space. To reduce the pressure on the packing piece 11 as much as possible spring loaded levers engaging with said packing piece have been provided in order that the packing piece shall be relieved of all injurious and unnecessary strain to such an extent that it shall be possible for it to give satisfactory service even under -the most unfavourable conditions.

In the alternative construction illustrated, the rotary valve 6 is located within a housing 4 formed as a cylinder head, said rotary valve being provided with two passages 9 and 10 which permit of the admission of fresh mixture and the discharge of exhaust gases respectively. I r

A movable packing piece 11 is arranged between the cylinder and the rotary valve 6, said packing piece being jointed with the cylinder in a gas tight, although flexible.

manner by means of the diaphragm 12, the inner flange part of which is connected to the packing piece 11 whilst the other flange of the diaphragm 12 is engaged with the cylinder head by means of the collar 14. 1

To prevent the hot cylinder gases from passing through the annular space 23 between the rings 13 and 1 4, attacking the dia-' phragm 12 and inuriouslyheating it, a pack 'ing ring 24 is arranged in .a grooveexternally arranged on the screwed ring1 3, said oint ring elastically engaging with; the .in-

ternal bore of the ring 14 so as to isolate the space 23 in a permanent and reliable manner thus enabling the diaphragm 12 to be-un influenced by the hot cylinder gases; To prevent the diaphragmf12-taking a per nlanentset owing to the continuous loading thereof by the weight of the packing piece 11 and the pressure due to the-operation of the piston during the suction stroke and the following pressure owing to the compression, radial bores 25 are arranged in thecylinden head. each of said bores beingprovided with a double armed lever 26, 27 one of the ends of each 'of said levers engaging in a corresponding recess in the packing piece 11 whilst the other free end of each of said levers is .loaded by means of compression springs28 in such manner that the packing piece 11 is permanently pressed against the circum-fer ence of the rotary valve 6. For the purpose of facilitating the fitting of the levers 26 and 27 they are conveniently given the slender, tapered shape illustrated in Figure 12 which offers the advantage that the levers 2 6 and 27 lie at the bottom of the bores 26 with their rounded off shoulders acting as a fulcrum thusobviating the necessity for any special bearings. Externally, the recesses 25 are closed by means of plates 29.

Proper contact between the rotary valve and the packing piece 11, alternatively, may

be effected by means of spring loaded draw rods operating from .above, spring loaded pressure pins operating from below, or by any spring devices operating in an equivalent manner.

The cooling of the rotary valve is effected in a manner described and claimed in a divisional application identified bySerial Number 514.683. filed Feb. 6, 1931.

Further, it will be seen that owing to the supplemental packing ring 24 access by the hot cylinder gases to the diaphragm 12 is prevented thereby obviating any possibility of the diphragm 12 being directly effected by such hot cylinder gases.

Obviously, the invention may be put into effect in a variety of ways and those described and illustrated must be considered to be by way of example only.

1. Improved packing for the rotary valves of internal combustion engines of the type specified, said improved'packing comprising,

a movable part cooperating with the surface of the valve, a stressedelasticannular diaphragm clamped by the inner periphery thereof to said movable part, andmeans clamping the outer peripherybf the diaphragm to the cylinder head so .as to prevent the leakage of gases from the cylinder.

2. Improved packing for the rotary valves of internal combustion engines of the type specified, said improved packing comprising a stressed elastic annular diaphragm of sheet metal with a head of semi-circular profile pressed therein between the inner and outer peripheries thereof; the inner periphery of each of said packing rings being clamped against an abutment on the movable part cooperating with the surface of the valve, and the outer periphery of each of said packing rings being clamped against an abutment in the cylinder head so as to prevent the escape of gases from the cylinder.

3. Improved packing for the rotary valves of internal combustion engines of the type specified, said improved packing comprising a stressed elastic annular diaphragm of sheet "metal with a bead of semi-circular profile pressed. therein between the inner and outer peripheries thereof; the inner periphery of each of said packing rings being clamped against an abutment on the movable part cooperating with the surface of the valve, the outer periphery of each of said packing rings being clamped against an abutment in the cylinder head so as to prevent the escape of gases from the cylinder; an opening in said movable part forcooperating with the inlet opening in the valve to allow of the admission of gas mixture to the cylinder; an opening in said movable part for cooperating with the exhaust opening in the valve to allow of the discharge of the products of combustion from the cylinder and parts cooperating with said valve for supplying gas mixture to and receiving products of combustion from said valve.

4. Improved packing for the rotary valves of internal combustion engines of the type specified, said improved packing comprising a stressed elastic annular diaphragm of sheet metal with a bead of, semi-circular profile pressed therein between the inner and outer peripheries thereof; the inner periphery of each of said packing rings being clamped against an abutment on the movable part cooperating with the surface of the valve, the

' outer periphery of each of said packing rings being clamped against an abutment in the cylinder head so as to prevent the escape of gases from the cylinder; an opening in said movable part for cooperating with the inlet opening in the valve to allow of the admission of gas mixture to the cylinder; an opening in said movable part for cooperating with the exhaust opening in the valve to allow of the discharge of the products of combustion from the cylinder; a hollow shoe located on the surface of the rotary valve for cooperating with the inlet opening in the valve, a second hollow shoe located on the surface of the rotary valve for cooperating with the pressed therein between the inner and outer peripheries thereof; the inner periphery of each of said packing rings being clamped against an abutment on the movable part cooperating with the surface of the valve. the outer periphery of each of said packing rings being clamped against an abutment in the cylinder head; a groove in the clamping means for the inner periphery; and additional packing means constituted by a spring jointing ring in said groove for cooperating with the surface of the clamping means for the outer periphery so as to prevent the cylinder gases from impinging on the diaphragm or escaping from the cylinder.

6. Improved packing for the rotary valves of internal combustion engines of the type specified, said improved packing comprising a stressed elastic annular diaphragm of sheet metal with a head of semi-circular profile pressed therein between the inner and outer peripheries thereof; the inner periphery of each of said packing rings being clamped against an abutment on the movable part cooperating with the surface of the valve; the outer periphery of each of said packing rings being clamped against an abu ment in the cylinder head so as to prevent the escape of gases from the cylinder; 'an opening in said movable part for cooperating with the inlet opening in the valve to allow of the admission of gas mixture to the cylinder; an opening in said movable part for cooperating with the exhaust opening in the valve to allow of the discharge of the products of combustion from the cylinder and parts cooperating with said valve for supplying gas mixture to and receiving products of combustion from said valve; means for preventing the cylinder gases from impinging on the diaphragm or escaping from the cylinder: means for cooling said rotary valve; a plurality of levers engaging by one end with said movable part; springs for engaging the free ends of each of the levers so as to press the movable-part into contact with the surface of the valve and counter-act the effect due to the suction of the engine.

7. Improved packing for the rotarv valves of internal combustion engines of the type specified. said improved packing comprising a stressed elastic annular diaphragm of sheet metal with a bead of semi-circular profile pressed therein between the inner and outer peripheries thereof; the inner periphery of each of said packing rings being clamped against an abutment on the movable part cooperating with the surface of the valve; the

outer periphery of each of said packing rings being clamped against an abutment 1n the cylinder head so as to prevent the escape of gases from the cylinder; an opening in said 5 movable part for cooperating with the inlet opening in the valve to allow of the admission of gas mixture to the cylinder; an opening in said movable part for cooperating with the exhaust opening in the valve to allow of the discharge of the products of combustion from the cylinder and parts cooperating with said valve for supplying gas mixture to and receiving products of combustion from said valve; means for preventing the cylinder gases from impinging on the diaphragm or escaping from the cylinder; means for cooling said rotary valve; a plurality of radially disposed bores in the cylinder head; a two arm-ed lever arranged in each bore and having a part thereof arranged to operate as a fulcrum; the inner ends of said levers engaging with the movable part whilst the outer ends of said levers are spring pressed so as to press the movable part into contact vwith the surface of the valve and counter-act the effect due to the suction inthe en e.

- ALFRED B ER.

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