DE3013512A1 - Vertical IC engine exhaust pipe - has open top end with cover disc spring and weight-loaded to close and carried by spring only - Google Patents

Abstract

The closure disc is particularly intended for mounting at the upwardly open top of a vertically extending i.c. engine exhaust pipe (2). It comprises a frame (10) secured to the pipe and carrying the swivelable disc (1) which closes under its own weight and opens under the pressure of the emerging exhaust gas. The disc is carried in the frame via one or two torsion springs (3,4), fixed to the frame and the disc. The swivel pivot (7) of the disc is formed by the torsional axis (6) of the spring only. There may be one spring fixed to the frame at both ends (17, 18) and having an uncoiled portion to which the disc is secured.

Description

Exhaust flap for vertically upwards protruding

Exhaust Pipes The invention relates to an exhaust flap, in particular for the arrangement at the outlet end of vertically upwardly protruding exhaust pipes of internal combustion engines, consisting of a pivotable in one on one Exhaust pipe mountable frame mounted and under its weight against the outlet end pivoting flap cover, which is under the pressure of the exiting gas from the exit end can be withdrawn.

Such exhaust flaps are mainly used in construction machines with vertical provided upwardly guided exhaust pipe.

They are used to cover the exhaust opening when the engine is not running Weather conditions to damage the engine (internal combustion engine) and muffler to avoid.

Flaps of this type work automatically depending on the exhaust gas pressure. The gas flow created when the engine is running opens up due to the back pressure the flap cover, which increases when the gas pressure drops due to excess weight automatically closes and thus completely closes the exhaust port when the engine is at a standstill.

Flaps of this type usually consist of one, the exhaust port covering lid, which is expediently mounted so that the resulting Gas pressure creates an opening moment on the lid, against its natural closing moment generated from its own weight. If necessary, the correct closing torque will be matched by an additional cover counterweight. To limit the opening angle 5 of the flap cover, a stop is attached if necessary.

The flap cover is stored at two individual storage locations, which are designed in the form of plain bearings with the required clearance. The system flap cover, counterweight and bearing points form together with one A frame that can be clamped onto the exhaust pipe is an easily attachable unit.

The problem with these flaps is the plain bearing, which is used for the function requires sufficient bearing play and is subject to heavy wear, which leads to loud noises due to vibrations of the flap cover, which u. U. drown out the noise of the machine. When this state is reached, a Flap replacement required, but mostly because of recurring failures no further replacement is required and the exhaust pipe is removed after the Motor is covered, for example, with a canned food can.

The non-function of such flaps leads to the fact that the manufacturers of completely refrain from using them and provide the end of the exhaust pipe with a bend, the so shaped is that rain does not normally get into the exhaust pipe can penetrate.

To avoid increased sound level values that are specified by law prescribed all-round measurement on the vehicle, it is necessary, however, to measure the exhaust sound to be diverted vertically upwards and not sideways.

The invention is based on the object of providing an exhaust flap of the initially called type so that a noiseless and low-wear operation the flap is possible.

To solve this problem, the at the beginning is used for an exhaust flap mentioned type proposed that the flap cover in the frame at least a torsion spring is suspended freely pivotable on the one hand on the frame and on the other hand is attached to the flap lid, the pivot axis of the flap lid is formed solely by the torsion axis of the torsion spring.

The invention is based on the knowledge that such a flap does not need to be stored in a rigidly defined pivot axis and straight for such freely movable flaps an "elastic" axis is useful, which need not be precisely defined in their position.

The pivot axis of the flap through the torsion axis is sufficient Torsion spring to be defined and sufficiently determined. In addition, it is possible the closing torque of the flap cover by pre-setting the torsional preload adjust the spring. Corresponding embodiments are in the subclaims marked.

Exemplary embodiments of the invention are set out below described in more detail with reference to the accompanying drawing. 1 is shown in perspective View of a first embodiment of an exhaust flap with a closed flap cover; FIG. 2 shows, in a reduced representation, the embodiment according to FIG. 1 with the open Flap cover; and FIG. 3 is a perspective illustration of a second embodiment.

The exhaust flap consists of a flap cover 1, which is the outlet end of the exhaust pipe 2 covered and from a frame 10, which by means of a clamp 16 and a clamping screw 11, not shown, can be fastened to the exhaust pipe 2 is. The flap cover 1 is each a torsion spring 3 and 4, which is shown in the Embodiment are designed as spiral springs, suspended in the frame. Included the springs 3 and 4 are at a distance -5 from the exhaust pipe axis on the flap 1, the springs are aligned with their axes 6 and form the pivot axis 7 of the flap 1 by at the ends facing away from the flap 1 in the frame 10 are hung in openings 17, 18. By turning the spiral springs 3 and 4 before hanging in the openings 17, 18 or by applying tension on the springs 3.4 by hanging at a distance from their free end can the Torsional pretensioning of the springs and thus the closing torque of the flap cover 1 can be set. The openings for hooking springs 3 and 4 into the flap cover 1 are with 9, their distance with 8.

In the embodiment shown in Figure 3 is a continuous spiral spring 13 is provided, which is soldered at its free ends at 15 to the frame and has a non-spiral central region 19 which, as indicated by 14, is soldered to the flap cover 1.

L e r s e i t e

Claims (5)

CLAIMS g Exhaust flap, especially for the arrangement at the outlet end of exhaust pipes of internal combustion engines that protrude vertically upwards from a pivotable frame mounted in a frame that can be fastened to an exhaust pipe and under its weight against the outlet end of the hinged lid can be lifted from the outlet end under the pressure of the exiting gas, d a d u r c h g e k e n n n z e i c h n e t that the flap cover (1) in the frame (10) over at least one torsion spring (3, 4; 13) is suspended freely pivotable, on the one hand is attached to the frame (10) and on the other hand to the flap cover (1), the Pivot axis (7) of the flap cover (1) solely through the torsion axis (6) of the torsion spring (3, 4; 13) is formed. 2. Exhaust flap according to claim 1, characterized in that the Torsion spring is a spiral spring (13) which is attached to the frame (10) with both ends is attached and is connected in its central region (19) to the flap cover. 3. Exhaust flap according to claim 2, characterized in that the Spiral spring (13) has a straight, non-spiral central region (19) on which the flap cover (1) is attached. 4. Exhaust flap according to claim 1, characterized in that the Torsion spring consists of two aligned spiral springs (3, 4) whose one end each on the frame (10) and the other end each on the flap cover (1) is attached. 5. Exhaust flap according to one of the preceding claims, characterized characterized in that at least one end of each spiral spring (3, 4) into an opening (9; 17, 18) of the frame / flap cover is releasably suspended, whereby by turning and / or tensile prestressing of the spiral spring (3, 4) before hanging the torsional force and thus the closing torque of the flap cover (1) can be adjusted.