DE1037204B - Silencer for pulsating currents, especially for the exhaust of motorcycle engines - Google Patents

Description

GERMAN

The invention relates to a muffler for pulsating flows, in particular for the Exhaust from motorcycle engines, with a bell-shaped built-in part dividing its interior, which with the cylindrical outer jacket 5 is closed and narrowing towards the rear Forms nozzle-shaped annular space, which with the interior enclosed by the built-in part through openings is connected, and its main purpose is to improve sound absorption with good engine performance and simple design. The invention consists essentially in that the specified openings In a manner known per se, offset from one another in the longitudinal and transverse directions, preferably on one are arranged over the circumference extending helical line, wherein the annular space is a vestibule possesses that from the exhaust pipe or from the antechamber connected to this through a flow cross-section narrowing perforated wall, e.g. B. a known, tapered in flow directions Sieve funnel or a sieve screen curved convexly to it is separated.

There are known silencers in which the gases passed through a plurality of external channels which are arranged in a ring around an inner space with which they pass through a helically extending slot-like opening are connected, the outer channels as well the inner space also open out into a common downstream space. A jet shaped however, there is just as little a narrowing annulus with individual passage openings that are offset from one another such as a sieve screen or a sieve funnel.

Furthermore, silencers are known, the inlet port of which has a conical extension in the cylindrical Open into the silencer housing, which is funnel-shaped through evenly spaced holes Partition walls are divided into several relaxation chambers. These seven are inter- Differential effects can be achieved due to the evenly arranged openings. But is the well-known Construction relatively cumbersome due to several built-in partition walls, so that the Damping can only be achieved with a relatively large construction effort.

In contrast, in the case of the invention, on the one hand, an interference effect and, on the other hand, that a sieve funnel, a sieve screen or the like is connected upstream of the annular nozzle-shaped space, an effective division of the incoming pressure and sound waves as well as an equalization of the same achieved, so that a high damping silencer due to the overlapping division and interference effect for pulsating currents,

especially for the exhaust

of motorcycle engines

Applicant:

Friedrich Boysen,

Stuttgart-Heumaden, Im Sonnenweg 29

Friedrich Boysen, Stuttgart-Heumaden,
has been named as the inventor

degree of efficiency can be achieved. As a result of the simple gas flow, which is largely adapted to the flow At the same time, the lowest power losses result.

The simple structure of the muffler also allows easy assembly of the same by, for. B. held in a known manner, with its at the end of muffler shell axially adjacent outwardly bent flanged bell-shaped mounting portion characterized in that the end cap engages in a known manner shaped S-bent with its edge the muffler shell and arranged centrally by means of one and the mesh funnel or is pressed against the clamping bolt attached to the screen.

Further features and advantages of the invention can be found in the description of two shown in FIGS Refer to exemplary embodiments.

In the embodiment of Fig. 1, the muffler consists of a to the outlet pipe of the Motor adjoining conically flared part 10, a cylindrical part 11 and a conical narrowing part 12. In the conically widening part 10 is a funnel-shaped narrowing throat Tube 13 is inserted, in whose narrowed opening directed to the rear a longitudinal bolt 14 is inserted. On the latter is a bell-shaped built-in part 15 attached, e.g. B. welded on. This has inwardly punched wall parts formed scoop-like outlet openings 16 which lie on a helical line. The built-in part 15 expands here conically backwards, so that between the outer cylindrical wall 11 and the inner wall 15 formed, with the chamber 17 in open communication annular space 18 itself

. 809 598/297

constricted in cross section towards the rear like a nozzle. In The inner chamber formed within the bell-shaped built-in part 15 expands to the same extent 19, which attenuates within the sound it ferteil 12 in the rearwardly conically narrowing chamber 20 passes. A tube 21 is inserted into the rear opening of the muffler part 12, which in the enclosed by the mounting part 15 interior 19 protrudes so far forward that its front The inlet opening 22 is located in front of the outlet openings 16 of the annular nozzle space 18. The tube 21 is closed to the rear by a transverse wall 23, through which the longitudinal bolt 14 .through inserted which can be secured by a nut 24.

The gases flowing through the tube 21 can pass through lateral openings 25 and through the expanded Drain pipe 26 to the outside.

After unscrewing the nut 24, the cap-shaped end part 12 of the silencer together with the tube 21 can be pulled out to the rear. If necessary, the front fittings, in particular the built-in part 15 and the funnel-shaped narrowing tube 13 together with the longitudinal bolt 14 can be removed from the muffler.

In the embodiment according to FIG. 2, the curved outlet pipe 30 consists of the three parts 31, 32 and 33 existing silencers are added. The inlet chamber 34 is through an against the exhaust pipe of the motor concave curved perforated wall 35 completed, in which the longitudinal bolt

36 is welded to hold the removable end part 33 in place.

Similar to the embodiment according to FIG. 1, a bell-shaped built-in part is also in this case

37 is provided, which narrows a nozzle-shaped, standing in open connection with the chamber 38 Annular space 39 and an inner space 40 forms, the annular space 39 and the inner chamber 40 are connected by passage openings 41 arranged on a helical line. The openings 41 are designed as simple holes in this case. Those entering the interior 40 Gases escape from an outlet pipe 42 arranged eccentrically in the chamber.

Claims (2)

Patent claims: 1. Silencers for pulsating currents, especially for the exhaust of motorcycle engines, with a bell-shaped built-in part dividing its interior space, which is connected to the cylindrical outer jacket a closed and narrowing nozzle-shaped towards the rear Forms an annular space which is connected to the interior space enclosed by the built-in part through openings is, characterized in that these openings (16, 41) in a manner known per se offset from one another in the longitudinal and transverse directions, preferably on one extending over the circumference Helical lines are arranged, the annular space (18, 39) having an anteroom (17.38), from the exhaust pipe (30) or from the antechamber (10, 34) connected to it a perforated wall narrowing the flow cross-section, e.g. B. a known per se, in Sieve funnel tapered in the direction of flow or a sieve diaphragm (35) curved convexly towards it is separated. 2. Silencer according to claim 1, characterized in that in a known manner with its outwardly bent beaded edge at the end of the muffler jacket (11, 32) axially adjacent bell-shaped built-in part is held in that the end cap (12, 33) in known Way with its S-shaped upturned edge surrounds the muffler shell and means one arranged in the middle and attached to the sieve funnel (13) or to the sieve screen (35) Clamping bolt (14, 36) is pressed. Considered publications: German Patent Nos. 338 453, 460 885, 618, 638 787, 654 804, 736 944, 841 833, 850 536; Swiss Patent No. 191 766; French Patent No. 695 510; German utility model No. 1659424, 1661717; Yearbook of internal combustion Society, Berlin, 1938, p. 73; Communications from T. H. Dresden (Institute for Motor Vehicles), 1931, p. 23. 1 sheet of drawings Θ 509 593/297 &.