US3219144A

US3219144A - Valve-like silencer on end of exhaust pipe

Info

Publication number: US3219144A
Application number: US122189A
Authority: US
Inventors: Murray Ernest; Murray Kathleen
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-07-06
Filing date: 1961-07-06
Publication date: 1965-11-23
Anticipated expiration: 1982-11-23

Description

Nov. 23, 1965 E. MURRAY ETAL 3,219,144

VALVE-LIKE SILENCER ON END O F EXHAUST PIPE Filed July e. 1961 l Fig 1.

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43%@ ma M "d WL United States Patent O 3,219,144 VALVELIKE SILENCER N END 0F EXHAUST PIIIE Ernest Murray and Kathleen Murray, Coddington, Engiand, assignors of one-half to William Marvin Pierson,

Pleasant Grove, Utah Filed .Iuly 6, 1961, Ser. No. 122,189 2 Claims. (Cl. 181-65) This invention relates to improvements in apparatus for silencing the exhaust .systems of internal combustion and other engines. The object of the present invention is to provide apparatus which can be fitted to the outlet end of an engine exhaust pipe and which will effectively reduce the noise of the exhaust and which will automatically adjust itself according to the volume of the exhaust gases passing through the exhaust system.

According to this invention the apparatus for silencing the exhaust system of an engine comprises a valve member slidingly mounted on the end of the exhaust pipe and held by a spring onto a seat to close the end of the exhaust pipe when the engine is stationary and which is moved from its seat, against the action of the spring, by the exhaust gases when the engine is Working, to allow the exhaust gases to escape, the movement of the valve from its seat depending on the volume of exhaust gases passing along the exhaust pipe at any given time. The valve is preferably a cylindrical member closed at its outer end and slidingly mounted on the outer side of the end of the exhaust pipe, a spring being provided to move the inner end of the cylindrical member towards a seat provided on the exterior of the exhaust pipe. A space of suitable size is provided between the inner side of the cylindrical member and the outer side of the exhaust pipe for the passage of the exhaust gases when the valve is opened by the exhaust gases. The cylindrical member is preferably provided with a sound absorbing lining.

The invention will now be more particularly described with reference to the accompanying drawings in which:

FIG. 1 is an axial longitudinal vertical section of silencing apparatus for the exhaust systems of internal combustion and other engines constructed according to this invention.

FIG. 2 is a transverse cross section on the line 22 of FIG. l.

FIG. 3 is a plan View partly in section showing the valve open.

FIG. 4 is an elevation, partly in section, showing an alternative form of construction and FIG. 5 is a fragmentary side elevation of a modied form of coupling member for attaching the valve to the end of an exhaust pipe.

Like letters indicate like parts throughout the drawings.

In one method of carrying out this invention the apparatus is formed from a cylindrical tube 1 of suitable length which is closed at its outer end. The tube 1 is slidingly mounted on the end 2 of the exhaust pipe or an extension attached thereto, see FIGURE 5, and for this purpose the outer side of the exhaust pipe or extension is formed with a plurality of longitudinal ribs 3 the outer edges of which engage with the inner side of the liner 6 therein and hold the tube concentric with the exhaust pipe 2. The ribs 3 are equidistantly spaced round the exhaust pipe 2 and may conveniently comprise four in number. The space formed between the exterior of the exhaust pipe 2 and the inner side of the liner provides passages 15 for the exhaust gases and the internal diameter of the tube 1 or liner is made suitable to the cubic capacity of the engine with which it is to be used.

A coil spring 4 is connected between the end of the tube 1 and a cross member S fixed in the exhaust pipe 2. Provision is made to adjust the tension of the Spring 4 so that its pull on the tube 1 can be adjusted by connecting the end of the spring to the end of the tube 1 by a screweye 16. The spring 4 moves the open end of the tube 1 towards a seat which may comprise the conical end of a casing secured to the outside of the exhaust pipe or the seat may be formed by the end of an expansion chamber normally provided in the exhaust pipe.

The tube 1 is preferably provided with a lining 6 of suitable sound absorbing material and the outer end of this lining 6 is drawn by the spring 4 towards a conical seat 7 which may be formed by the outer side of an expansion chamber 8 provided in the exhaust system and as shown in FIGS. 1 to 4 or a seat 17 may be formed on a casing 9 for attachment in Well known manner to the end of an existing exhaust pipe as shown in FIG. 5 In order to prevent the tube 1 being forcibly pulled off the exhaust pipe 2 and the spring 4 strained, a check wire 10 (FIGS. 1, 2 and 3) is provided which limits the movement of the tube 1 away from the seat 7.

Instead of a coil spring disposed inside the tube as described above, a coil or other form of spring or springs may be disposed outside the tube and connected between the tube and a xed point and adapted to move the tube towards its seat. With heavy or large cubic capacity engines or exhaust systems the tube may be o-perated by a leaf spring or springs which are also adapted to support the tube independently of the existing exhaust system.

In `an alternative construction shown in FIG. 4, the tube 1 is arranged to slide freely in an outer casing 11 which is secured to the casing on which the seat 7 is formed. The tube 1 is moved towards the seat '7 by a compression spring 12 disposed between the end of the tube 1 and the end 13 of the casing 11.

When the engine is stationary the spring holds the open end of the liner 6 on the seat 7 provided and in this position the other end of the tube 1 is a suitable distance from the end of the exhaust pipe 2. When the engine is `started the exhaust gases therefrom move the l-iner 6 away from the seat 7 and the exhaust gases escape through the opening between the end of the liner 6 and the seat 7 with a considerable reduction in the noise of the exhaust. The distance the liner 6 moves away from its seat depends on the volume of the exhaust gases at any given time so that the amount the valve opens is automatically controlled by the volume of the exhaust gases. The tube 1 may be composed of any suitable sound absorbing material or it may comprise a metal tube with a lining 6 of sound absorbing material as shown in the drawings.

Apparatus constructed as described when attached to the exhaust pipe of an internal combustion engine effects a considerable reduction Iin the noise of the exhaust with a consequent reduction in the strain on the driver of a vehicle to which it is fitted and also reduces to a minimum the noise nuisance to the general public and Without any apparent effect on the efficient working of the engine.

What we claim is:

1. In combination, an exhaust pipe of an internal combustion engine, a tubular extension therefrom, spaced longitudinal ribs on the extension, a tube with a closed end slidably carried on said ribs, and spring means for impelling the open end of the tube toward the exhaust pipe.

2. In combination, an exhaust pipe of an internal combustion engine, a tubular extension therefrom, spaced longitudinal ribs on the extension, a tube with a closed end slidably carried on said ribs, a cross member in the extension, and a coil spring connecting the cross member to the closed end of the tube.

(References on following page) References Cited by the Examiner UNITED f1 FOREIGN PATENTS 33,263 5/1924 Denmark. STATES PATENTS 361,422 7/1938 Italy. Hensley 181--65 X 141,386 10/1930 Switzerland. Culp 181-65 5 Feyens 131 65 X LEO SMILOW, Primary Examiner. KrStiaHSIl 18150 X C. W. ROBINSON, Examiner.