Sliding cam system for an internal combustion engine

Abstract

A sliding cam system for an internal combustion engine is disclosed. The sliding cam system includes a carrier shaft and an axially adjustable cam sleeve arranged on the carrier shaft. The cam sleeve is axially adjustable relative to the carrier shaft between a first axial position and a second axial position, and axially fixable in the respective axial position by a detent device. The detent device includes a first receiving groove assigned to the first axial position and a second receiving groove assigned to the second axial position. The detent device further includes a preload element disposed on the cam sleeve. The preload element preloads a detent element arranged between the carrier shaft and the cam sleeve towards the carrier shaft. The detent element is received in the first receiving groove in the first axial position and the second receiving groove in the second axial position.

1 . A sliding cam system for an internal combustion engine, comprising:
 carrier shaft extending along an axial direction,   at least one sleeve-shaped cam sleeve arranged on the carrier shaft radially outside and axially adjustable relative to the carrier shaft, the at least one sleeve-shaped cam sleeve including at least one cam profile,   the carrier shaft and the at least one cam sleeve for the transmission of torque being non-rotatably connected to one another,   the at least one cam sleeve being axially adjustable relative to the carrier shaft between a first axial position and at least one second axial position and axially fixable in a respective one of the first axial position and the at least one second axial position on the carrier shaft via a detent device wherein the detent device includes:   a first receiving groove assigned to the first axial position and a second receiving groove assigned to the at least one second axial position, wherein the first receiving groove and the second receiving grooves are axially spaced apart from one another and each extend along an outer circumference of the carrier shaft, and   a preload element disposed on the at least one cam sleeve, wherein the preload element preloads a detent element arranged between the carrier shaft and the at least one cam sleeve towards the carrier shaft, and wherein the detent element is received in the first receiving groove when the at least one cam sleeve is located in the first axial position and received in the second axial groove when the at least one cam sleeve is located in the at least one second axial position.   
     
     
         2 . The sliding cam system according to  claim 1 , wherein the preload element is a detent spring arranged in a receptacle disposed on the at least one cam sleeve and exerts a preload force on the detent element. 
     
     
         3 . The sliding cam system according to  claim 1 , further comprising a receptacle structured as an opening extending radially in the at least one cam sleeve and a support element received in the receptacle, wherein the preload element radially supports itself on the support element radially outside for generating a preload force. 
     
     
         4 . The sliding cam system according to  claim 3 , wherein:
 the opening is structured as a through-bore, and   the support element present in the through-bore is firmly connected to the at least one cam sleeve via a press connection and arranged fixed in place relative to the at least one cam sleeve.   
     
     
         5 . The sliding cam system according to  claim 3 , wherein the support element includes an external thread, which for the radial adjustability of the support element engages in an internal thread provided on the opening formed complementarily to the external thread, such that the support element is radially adjustable relative to the at least one cam sleeve. 
     
     
         6 . The sliding cam system according to  claim 3 , wherein the support element is structured as a threaded pin. 
     
     
         7 . The sliding cam system according to  claim 3 , further comprising a sleeve-shaped housing delimiting a housing interior provided on the support element, wherein the preload element and the detent element are each at least partially received in the housing interior. 
     
     
         8 . The sliding cam system according to  claim 7 , wherein the support element, the preload element, the detent element and the sleeve-shaped housing are provided integrally as a unit. 
     
     
         9 . The sliding cam system according to  claim 1 , wherein the detent element is formed structured as a detent ball. 
     
     
         10 . The sliding cam system according to  claim 1 , wherein a radius of the carrier shaft is reduced in an axial region between the two first receiving groove and the second receiving grooves. 
     
     
         11 . The sliding cam system according to  claim 1 , wherein:
 the first receiving groove and the second receiving grooves each comprise a groove base and a first groove flank and second groove flank, wherein the respective first groove flanks have a smaller axial distance to the respective other receiving groove than the respective second groove flanks; and   wherein in at least one of the first receiving groove and the second receiving groove the first groove flank and the second groove flanks are each arranged at a first acute angle and a second acute angle respectively to a radial direction, wherein a first angular value of the first acute angle is greater than a second angular value of the second acute angle.   
     
     
         12 . The sliding cam system according to  claim 1 , wherein a radially measured depth of at least one of the first receiving groove and the second receiving groove amounts to maximally 10%, of a radius of the carrier shaft. 
     
     
         13 . An internal combustion engine for a motor vehicle, comprising:
 at least one cylinder comprising a combustion chamber provided with an inlet valve for introducing fresh air into the combustion chamber and an exhaust valve for discharging exhaust gas out of the combustion chamber are provided, and   at least one sliding cam system for controlling at least one of the inlet valve and the exhaust valve, the at least one sliding cam system including:   a carrier shaft extending along an axial direction;   at least one sleeve-shaped cam sleeve arranged on the carrier shaft radially outside and axially adjustable relative to the carrier shaft, the at least one sleeve-shaped cam sleeve including at least one cam profile;   the carrier shaft and the at least one cam sleeve for the transmission of torque being non-rotatably connected to one another;   the at least one cam sleeve being axially adjustable relative to the carrier shaft between a first axial position and at least one second axial position and axially fixable in a respective one of the first axial position and the at least one second axial position on the carrier shaft via a detent device, wherein the detent device includes:   a first receiving groove assigned to the first axial position and a second receiving groove assigned to the at least one second axial position, wherein the first receiving groove and the second receiving groove are axially spaced apart from one another and each extend along an outer circumference of the carrier shaft and   a preload element disposed on the at least one cam sleeve, wherein the preload element preloads a detent element arranged between the carrier shaft and the at least one cam sleeve towards the carrier shaft, and wherein the detent element is received in the first receiving groove when the at least one cam sleeve is located in the first axial position and received in the second axial groove when the at least one cam sleeve is located in the at least one second axial position.   
     
     
         14 . The internal combustion engine according to  claim 13 , wherein the preload element is a detent spring arranged in a receptacle disposed on the at least one cam sleeve and exerts a preload force on the detent element. 
     
     
         15 . The internal combustion engine according to  claim 14 , wherein the receptacle is structured as an opening extending radially in the at least one cam sleeve and a support element is received in the opening, wherein the detent spring radially supports itself on the support element radially outside for generating the preload force. 
     
     
         16 . The internal combustion engine according to  claim 15 , wherein the support element includes an external thread that engages an internal thread provided on the opening such that the support element is radially adjustable relative to the at least one cam sleeve. 
     
     
         17 . The internal combustion engine according to  claim 15 , further comprising a sleeve-shaped housing delimiting a housing interior provided on the support element, wherein the detent spring and the detent element are each at least partially received in the housing interior. 
     
     
         18 . The internal combustion engine according to  claim 13 , wherein the detent element is structured as a detent ball. 
     
     
         19 . The internal combustion engine according to  claim 13 , wherein a radius of the carrier shaft is reduced in an axial region between the first receiving groove and the second receiving groove. 
     
     
         20 . The internal combustion engine according to  claim 13 , wherein a radially measured depth of the first receiving groove and the second receiving groove amounts to 10% or less of a radius of the carrier shaft.