DE3933920A1 - V=belt gear for infinite adjustment - has quieter operation through sound absorbing layers and non-metal cast material - Google Patents

Abstract

The V-belt gear for infinite adjustment has cast aluminium cone discs arranged in pairs and locally fixed and/or axially displaceable against the force of a spring or hydraulic or pneumatic cylinder. A non-metallic sound absorbing layer (5) is mounted on the outside (1) of one or more cone discs (2,3) and a non-metallic cast mass (4) is mounted in the disc ribbing (11). The sound absorbing layer is covered by a thin plate (6) of metal which is fixed on the cone disc (2,3) and is sunk flush in the outside (1). ADVANTAGE - A clear redn. in the operating noises.

Description

The invention relates to a V-belt transmission for stepless Regulation with fixed and / or counter-arranged in pairs the effect of a back pressure (spring or hydraulic or Pneumatic cylinder) axially displaceable conical disks Cast aluminum or air conditioning and / or ventilation systems are equipped with such a V-belt transmission.

Such V-belt transmissions are for example in the DE-PS 8 19 937, 9 22 979 and 12 92 989 described. With these V-belt drives are through two pairs of conical pulleys an endless normal or wide V-belt together bound between the tapered inner surfaces of the discs a pair of disks is arranged. Become the two cones discs of a pair of conical disks with the help of a ver adjusting device steplessly approached each other, so wanders the V-belt between the cone pulleys to the outside edge of the conical disks and moves at the same time the other pair of conical disks towards its axis of rotation and vice versa, whereby stepless speed changes between the two pairs of conical disks can be achieved.

Those rotating at 1500 revolutions per minute, for example Conical disc pairs develop quite a strong noise winding, because of conical disk pairs made of cast aluminum the greater Brinell hardness is significantly higher than with Verwen cast iron discs. This is higher noise very disruptive in ventilation and air conditioning technology.

The invention has for its object this materialbe indispensable to reduce noise levels and to reduce the noise level of gray cast iron discs or to even lower values to reduce.  

This object is achieved according to the invention with a wedge belt transmission of the type mentioned in that at the One outside of one or more conical washers is not metallic structure-borne sound insulation layer or a non-metallic Potting compound arranged in the ribbing and through a thin plate attached to the conical disk - preferably made of metal - is covered.

Preferably, the thin metal plate is on the outside of the Tapered disc sunk and arranged flush with it.

The invention is in one embodiment below explained in more detail with reference to the drawing, the pair of conical pulleys shows in longitudinal section.

The two conical disks 2 and 3 have different distances from one another under the action of the axially acting spring 9 or a hydraulic or pneumatic matikzylinders, so that the arranged between the conical disks 2 and 3 on the opposite inner sides 8 , 8 of the conical disks 2 and 3 engaging V-belt 7 alternately in a near-axis and an off-axis position.

A disk ribbing 11 is provided on the outer sides 1, 1 of the conical disks 2 and 3 for reasons of reinforcement.

According to the invention it is proposed either to introduce a non-metallic casting compound 4 as structure-borne sound insulation layer between the conical disk ribbing, or to apply a structure-borne sound insulation layer 5 to the ribbing 11 and this structure-borne sound insulation layer 4 or 5 by a thin plate 6 fastened to the conical disk - preferably covered from metal.

The attachment of the cover plate 6 on the conical pulleys 2 and 3 can be accomplished with any fastening means - for example, by gluing or by clamping ring closure - or by the fastening screws 10 shown in the exemplary embodiment.

This kind of sandwich construction leads to a significant reduction of operating noise, which is an improvement of 4.35 dB, corresponding to max. 65% rendered. Conical disks made of aluminum cast iron therefore run even quieter than gray cast iron discs. Before is part that the conical disks made of cast aluminum with the same unchanged tools can be manufactured as until now. The significant reduction in noise is only due to not very complex, additional cultivation measures achieved.

Claims (4)

1. V-belt transmission for infinitely variable control with fixed pairs and / or axially displaceable conical disks made of cast aluminum against the action of a spring or a hydraulic or pneumatic cylinder, characterized in that

• - On the outside ( 1 ) of one or more conical washers ( 2 , 3 ) a non-metallic structure-borne sound insulation layer ( 5 ) or a non-metallic casting compound ( 4 ) in the washer ribbing ( 11 ) and
• - Covered by a thin plate ( 6 ), preferably made of metal, attached to the conical disk ( 2 , 3 ).

2. V-belt transmission according to claim 1, characterized in that the thin metal plate ( 6 ) in the outside ( 1 ) of the conical disk ( 2 , 3 ) sunk and is flush with this is arranged. 3. Air conditioning and / or ventilation system with a V-belt gear for stepless control with paired angeord Neten stationary and / or against the action of a spring or a hydraulic or pneumatic cylinder axially sliding conical disks made of cast aluminum, characterized in that

• - On the outside ( 1 ) of one or more conical washers ( 2 , 3 ) a non-metallic structure-borne sound insulation layer ( 5 ) or a non-metallic casting compound ( 4 ) in the washer ribbing ( 11 ) and
• - Covered by a thin plate ( 6 ), preferably made of metal, attached to the conical disk ( 2 , 3 ).

4. Air conditioning and / or ventilation system with a V-belt transmission according to claim 3, characterized in that the thin metal plate ( 6 ) in the outside ( 1 ) of the conical disk ( 2 , 3 ) sunk and is flush with this is arranged.