Starting clutch

Abstract

The present invention provides a starting clutch disposed between a transmission and an engine and having a wet type multi-plate clutch for transmitting a power, in which the wet type multi-plate clutch includes a plurality of friction plates housed for an axial sliding movement, a clutch drum for housing the friction plates, and a piston for urging a radial central region or therearound of the friction plate to engage the friction plates, and oil which has lubricated the wet type multi-plate clutch is temporarily trapped within the clutch drum and then is discharged.

1 . A starting clutch disposed between an engine and a transmission and having a wet type multi-plate clutch for transmitting a power, wherein:
 said wet type multi-plate clutch comprises a plurality of friction plates housed for an axial sliding movement, and radial central regions of said friction plate are urged from both sides in an axial direction.   
   
   
       2 . A starting clutch according to  claim 1 , wherein said wet type multi-plate clutch includes a piston for urging the radial central region of said friction plate to engage said friction plates, and said piston has an axially extending protruded portion for urging the radial central region of said friction plate. 
   
   
       3 . A starting clutch according to  claim 2 , wherein an abutting member for abutting against said friction plate is provided at an opposite side from said piston, and said abutting member has an axially extending projection for urging the radial central region of said friction plate. 
   
   
       4 . A starting clutch according to  claim 3 , wherein said protruded portion of said piston and said projection of said abutting member are arranged on the same single line. 
   
   
       5 . A starting clutch according to  claim 1 , wherein said wet type multi-plate clutch comprises a plurality of friction plates housed for an axial sliding movement, and a clutch drum for housing said friction plates, and further wherein oil which has lubricated said wet type multi-plate clutch is trapped within said clutch drum and then is discharged. 
   
   
       6 . A starting clutch according to  claim 1 , wherein said wet type multi-plate clutch includes a piston for urging the radial central region of said friction plate to engage said friction plates, and said piston has an urging portion for abutting against said friction plate to apply an urging force to said friction plate, and a base portion connected to said urging portion, and said urging portion has is provided at its tip end with a curved portion protruding toward an abutting direction with respect to said friction plate. 
   
   
       7 . A starting clutch according to  claim 6 , wherein a member having a curved portion for abutting against said friction plate is provided at a position opposed to said piston with the interposition of said friction plates. 
   
   
       8 . A starting clutch according to  claim 6 , wherein said wet type multi-plate clutch comprises a plurality of friction plates housed for an axial sliding movement, and a clutch drum for housing said friction plates, and further wherein oil which has lubricated said wet type multi-plate clutch is trapped within said clutch drum and then is discharged. 
   
   
       9 . A starting clutch according to  claim 5 , wherein said clutch drum is not provided at its outer periphery with an oil discharging port extending in a radial direction. 
   
   
       10 . A starting clutch according to  claim 5 , wherein said clutch drum is provided at its inner periphery with spline grooves with which splines of said friction plates are engaged, and further wherein the oil is discharged through said spline grooves in the axial direction. 
   
   
       11 . A starting clutch according to  claim 5 , further comprising a cover member for covering an open portion of said clutch drum. 
   
   
       12 . A starting clutch according to  claim 11 , wherein said cover member is rotated together with said clutch drum to drive an oil pump. 
   
   
       13 . A starting clutch according to  claim 5 , wherein said clutch drum is covered by a clutch cover, and said starting clutch is housed in a housing, and said clutch cover is formed integrally with said housing. 
   
   
       14 . A starting clutch according to  claim 5 , wherein said clutch drum is covered by a clutch cover, and said starting clutch is housed in a housing, and said clutch cover is formed separately from said housing. 
   
   
       15 . A starting clutch according to  claim 5 , wherein a driving force from an engine is transmitted to said clutch drum through a housing. 
   
   
       16 . A starting clutch according to  claim 5 , wherein a driving force from an engine is transmitted from a housing member to said clutch drum through a damper device. 
   
   
       17 . A starting clutch according to  claim 15 , wherein a gap between the open end of said clutch drum and said housing member is narrower than other parts. 
   
   
       18 . A starting clutch according to  claim 15 , wherein said clutch drum is provided at its inner periphery with spline grooves with which splines of said friction plates are engaged, and further wherein the oil is discharged through said spline grooves in the axial direction. 
   
   
       19 . A starting clutch according to  claim 15 , wherein a cover member is provided to cover said wet type multi-plate clutch at an open portion of said clutch drum. 
   
   
       20 . A starting clutch according to  claim 19 , wherein, in an inner surface of said cover member or said housing, a protruded portion or a fin is provided on an inner diameter surface of said cover member to direct the oil discharged from the axial direction toward an inner diameter direction. 
   
   
       21 . A starting clutch according to  claim 19 , wherein, the lubricating oil passage for supplying the lubricating oil is separated from the lubricating oil passage for discharging the lubricating oil.