COVER FOR DRAW FRAMES Russian patent published in 2017 - IPC D01H1/16 

FIELD: textile, paper.

SUBSTANCE: housing for draw frames with a sound-insulating enclosure (a hinged lid), mounted on the machine's vibrating parts. The sound-insulating barrier is fixed to the head of the machine with combed strips with vibration and sound-insulating layers fixed onto the inner surface of the enclosure. The thickness of the vibration-absorbing layer is 2…4 times the thickness of the lid material. The elements of the housing are mounted onto the machine by means of rubber isolators, whose total rigidity is lower than the rigidity of the lid. According to the invention, a sound-absorbing sound-insulating element is designed as a rigid wall and a perforated wall, with two layers in between: a reflecting layer next to the rigid wall and a sound absorbing layer next to the perforated wall. A reflecting layer material is in the form of evenly distributed hollow tetrahedrons allowing to reflect the sound waves from all directions, and the perforated wall has the following perforation parameters: hole diameter - 3÷7 mm, percentage of perforations 10%÷15%. Holes can be of round, triangular, square, rectangular or diamond shape. In case of non-circular holes the nominal size is regarded as the maximum diameter of the polygon that fits in a circle; the used sound-absorbing material is basalt-based mineral wool basis. The surface of fibrous absorbers is covered with porous paints that let through air; or absorbing material of the sound absorbing unit of the soundproofing barrier is porous sound-absorbing material, such as foamed aluminium or cermets-shell rock or stone with a degree of porosity in the range of optimal values: 30÷45% or metal-based foam or material in the form of a compressed aggregate of solid vibration-damping material such as elastomer, polyurethane, or plastic, and porous mineral piece materials such as pumice, vermiculite, kaolin, slag cement or other binder, or synthetic fibers. The reflecting material of the sound-absorbing element of the body is made of aluminium alloys, subsequently filled with titanium hydride with the density of air within 0.5…0.9 kg/m³ with the following strength properties: compressive strength within 5…10 MPa, flexural strength in the range 10…20 MPa, such as foamed aluminium or sound insulating plate of glass staple fiber material with the density of 60÷80 kg/m³.

EFFECT: better noise reduction.

2 dwg