Patent ID: 6840876

Claim:
A variator for ratio adjustment of a continuously variable chain drive transmission, the variator comprising: a variator shaft ( 1 ); a variator pulley ( 2 ) supported on the variator shaft ( 1 ) and axially movable by pressurization supplied to at least one variator pressure chamber ( 31 ); the variator shaft ( 1 ) having an axial hole ( 10 ), formed in one end thereof, through which a supply of pressurized fluid to both the variator pressure chamber ( 31 ) and a second pressure chamber ( 8 ) can be provided independent of one another, a non-rotating pipe ( 7 ) being located within the axial hole ( 10 ) and have a central passage for supplying pressurized fluid to the second pressure chamber ( 8 ); wherein an exterior surface of the non-rotating pipe ( 7 ) and an inwardly facing surface of the axial hole ( 10 ) define therebetween a variator passageway, communicating with a radial hole ( 14 ) in the variator shaft ( 1 ), for suppling pressurized fluid to the variator pressure chamber ( 31 ); and the central passage and the variator passage are sealed with respect to one another; the exterior surface of the pipe ( 7 ) has two axially adjacent sealing rings ( 73 ) for dynamic sealing of the central passageway, which supplies pressurized fluid to the second pressure chamber ( 8 ), from the variator passage, which supplies pressure fluid to the variator pressure chamber ( 31 ); and a vent hole ( 9 , 92 ) is formed in the variator shaft ( 1 ) and a first end of the vent hole ( 9 , 92 ) communicates with an area of the non-rotating pipe located between the two axially adjacent sealing rings ( 73 ) while a second end of the vent hole ( 9 , 92 ) communicates with a transmission inner space ( 93 , 94 ) to facilitate venting to the transmission inner space ( 93 , 94 ) of any pressurized fluid which flows into the area located between the two axially adjacent sealing rings ( 73 ).