Sound-damping machine parts

Supporting machine parts (cheeks) and movable machine parts, especially levers of a machine are provided with interspaces and/or cavities (pores) for proofing against or the damping of sound vibrations or sound-generating vibrations, the interspaces and/or cavities being filled with a sound-proofing or sound-damping material.

1. Machine part having longitudinal and transverse dimensions and comprising: a supporting plate (10) comprising a hollow body having a cavity and having longitudinally and transversely directed partition walls (32) forming subsidiary cavities (22) within said hollow body, said subsidiary cavities (22) being filled with a liquid sound-damping material; intermediate bores (24), in said partition walls (32), providing liquid communication among said subsidiary cavities (22); and a filling orifice (23) for introducing the liquid material into said cavity.
2. The machine part according to claim 1, wherein said hollow body consists of a porous sintered metal having open pores (29) filled with a hardenable sound-damping plastic material.
3. A sound-damping machine part for supporting rotating elements within a machine, said machine part comprising:

a supporting frame (15);

bored bearings lugs (16) inside said supporting frame (15);

supporting webs (17) connecting the bearing lugs (16) to the supporting frame (15); and

sound-damping material filling interspaces (18) formed within the supporting frame between the supporting webs (17) and between said supporting frame (15) and said supporting webs (17).


4. The machine part according to claim 3, wherein said machine part consists of a porous sintered metal having open pores (29) filled with a hardenable sound-damping plastic material.
5. The machine part according to claim 3 or 4, characterized in that the bearing lugs (16) are each held by means of several supporting webs (17) whose number and dimensions are determined in accordance with loads exerted on said supporting webs (17) by rotating machine parts mounted in said bearing lugs.
6. The machine part according to claim 4, characterized in that the supporting frame (15) consists of an interconnected top spar (12) and bottom spar (11) each directed horizontally and connected to one another by means of two vertical side spars (13, 14), within which the supporting webs (17) are arranged.
7. The machine part according to claim 6, characterized in that the machine part has stays (25) pointing downward on an underside of said machine part, recesses (26) between the stays (25) being filled with the sound-damping material, whereby the machine part is adapted to stand not on said underside, but on the stays (25) and the sound-damping material.
8. The machine part according to claim 6, characterized in that the frame (15), the support webs (17), and the bearing lugs (16) have noses for fixing the sound-damping material in the interspaces(18).
9. The machine part according to claim 1, 3 or 4 wherein the material is a plastic polyurethane elastomer which has a characteristic of being in a liquid state only for filling and being hardenable after filling.
10. The machine part according to claim 6, wherein the frame (15), the support webs(17), and the bearing lugs (16) have ribs (19) for fixing the sound-damping material in the interspaces (18).
11. The machine part according to claim 6, wherein the frame (15), the support webs (17), and the bearing lugs (16) have ribs (19) for fixing the sound-damping material in the interspaces (18).

The invention relates to sound-damping parts which are provided with interspaces and/or cavities filled withsound-proofing or sound-damping material.

Machines with movable machine parts are known to be sources of sound-generating vibrations. Attempts have been made, hitherto, to prevent such vibrations by applying sound-deadening coatings to plate-like machine parts or by means of so-called impedance jumps in the form of abrupt variations in cross-section or the fitting of shock-absorbing elements. It is also known to encase sound sources in housings equipped with sound-deadening coatings and thus prevent the sound from radiating outwards.

A disadvantage of the abovementioned measures is that the actual control of the generation of noise or of the sound-generating vibrations takes place too far away from the point of origin, and because of this it is often necessary to provide a costly and expensive casing for the corresponding machine.