Development of New Type Rotary Compressors Suspended with Twin Springs in a Low Side Pressure Shell

This paper refers to the development of new type rotary compressors suspended with twin springs in a lo~ s1de pressure shell. We compared several types of compress~rs, for example h1gh side pressure shell type, low side pressure shell type, external-suspended type, internal-suspended type, and so on, from the viewpoint of noise reduction, vibration control and transient phenomena such as start-u~ noise. Based on these COIIIPUisons, It is proved that the low side pressure shell internal-suspended t1pe is most advanced. According to this result, new type rotary compressor was developed. It has twin verticallY faced springs to suspend the components of compression mechanism and of electric motor. But there were many difficulties, such as oil feeding, vane forcing, and so on, to accomplish this new type rotary compressor. By solving these difficulties, the new type rotary compressor achieved reduction in stationary noise of 6 (dbA), and start-up noise of 8 (dbA), in comparison with our previous 'odels, and it has only 1/~ the stationary vibration of the previous ones. l. INTRODUCTION The trend 1s that the lar~e-size refrigerator are more appreciated in Japanese market recently. The capacity of compressor for them, especialy rotary tJpes, need to be larger. In general, as the capacity of compressor ~et larger, noise level and vibration increase. To solve this problem, several tJpes of rotary compressor, for e~ample high side pressure shell type, low side pressure shell type, external-suspended type, internal-suspended type, and so on, were compared from the viewpoint of noise reduction, vibr•tion control and transient phenomena such as start-up noise. And at the same t1me, we compared the efficiency o! these types. 2. NOISE AND EFFICIENCY COMPARISON OF AMONG ROTARY COMPRESSORS 2. l STATIONARY NOISE COMPARISON Conrod reciprocating type compressor and rolling piston rotary type compressor are used for household refrigerator ordtnary. 9ut !rom the vtewp?int of downsizin~, reduction of weight and nigh .;ticJencJ, rotary type 4S used for mostlr household refrigerator 1n Japan. So our comparisons of noise reduction and vibration control were done among rotary types only.