Fluid dispenser member
A fluid dispenser member comprising a dispenser wall ( 23 ) defining an outside surface ( 231 ) and an inside surface ( 232 ), said wall ( 23 ) having a dispenser orifice ( 24 ) passing therethrough, connecting the inside surface to the outside surface, the inside surface ( 232 ) forming a sealing slide-cylinder ( 233 ) for a piston ( 3 ) that is suitable for being displaced, from a rest position, along an axis X in said cylinder and with leaktight contact, so as to open an outlet valve ( 25, 35 ), said piston ( 3 ) forming a portion of a fluid chamber ( 20 ) in which fluid is selectively put under pressure and flows through the open outlet valve towards the dispenser orifice, the piston forming a closure wall ( 34 ) that is suitable for closing the dispenser orifice ( 24 ) in the rest position, the closure wall ( 34 ) being positioned, in the rest position, over the dispenser orifice ( 24 ) beside its inside surface ( 232 ), the closure wall ( 34 ) coming into leaktight contact with the inside surface ( 232 ), the dispenser member being characterized in that, at the dispenser orifice ( 24 ), the inside surface ( 232 ) slopes relative to the displacement axis X of the piston ( 3 ), and the closure wall ( 34 ) of the piston ( 3 ) slopes in a manner that substantially corresponds to the inside surface ( 232 ), so as to create a cone-on-cone contact.
1. A fluid dispenser member comprising a dispenser wall ( 23 ) defining an outside surface ( 231 ) and an inside surface ( 232 ), said wall ( 23 ) having a dispenser orifice ( 24 ) passing therethrough, connecting the inside surface to the outside surface, the inside surface ( 232 ) forming a sealing slide-cylinder ( 233 ) for a piston ( 3 ) that is suitable for being displaced, from a rest position, along an axis X in said cylinder and with leaktight contact, so as to open an outlet valve ( 25 , 35 ), said piston ( 3 ) forming a portion of a fluid chamber ( 20 ) in which fluid is selectively put under pressure and flows through the open outlet valve towards the dispenser orifice, the piston forming a closure wall ( 34 ) that is suitable for closing the dispenser orifice ( 24 ) in the rest position, the closure wall ( 34 ) being positioned, in the rest position, over the dispenser orifice ( 24 ) beside its inside surface ( 232 ), the closure wall ( 34 ) coming into leaktight contact with the inside surface ( 232 ),
the dispenser member being characterized in that, at the dispenser orifice ( 24 ), the inside surface ( 232 ) slopes relative to the displacement axis X of the piston ( 3 ), and the closure wall ( 34 ) of the piston ( 3 ) slopes in a manner that substantially corresponds to the inside surface ( 232 ), so as to create a cone-on-cone contact.
2. A dispenser member according to claim 1 , in which, at the dispenser orifice ( 24 ), the outside surface ( 231 ) slopes relative to the axis X.
3. A dispenser member according to claim 1 , in which the dispenser wall ( 23 ) presents a thinner wall at the dispenser orifice ( 24 ).
4. A dispenser member according to claim 1 , in which the piston ( 3 ) forms a movable outlet-valve member ( 35 ) for coming into leaktight contact against an outlet-valve seat ( 25 ).
5. A dispenser member according to claim 4 , in which, a fluid passage is defined between the open outlet valve and the dispenser orifice, the passage being substantially filled in by the piston in the rest position, so as to reduce the dead volume.
6. A dispenser member according to claim 1 , in which the piston ( 3 ) is a differential piston that is displaced in response to a variation in the pressure in the fluid chamber ( 20 ).
7. A dispenser member according to claim 1 , in which the dispenser wall ( 23 ) is formed by a pusher ( 2 ) such that the piston ( 3 ) slides in the pusher, the outlet valve including a seat ( 25 ) that is formed by the pusher.
8. A dispenser member according to claim 7 , in which the pusher comprises a bearing wall ( 21 ) and a substantially-cylindrical peripheral skirt ( 22 ), the dispenser wall ( 23 ) being formed by the skirt, the skirt including a bottom end ( 26 ) that is engaged in an axial guide bushing ( 12 ) that advantageously serves as a support for a protective cap ( 5 ).
9. A fluid dispenser member comprising:
a dispenser wall defining an outside surface and an inside surface, said dispenser wall comprising a dispenser orifice connecting the inside surface to the outside surface, the inside surface forming a sealing slide-surface for a piston displaceable along a displacement axis X from a rest position and in leaktight contact with the inside surface, so as to open an outlet valve of the dispenser member;
said piston forming a portion of a fluid chamber in which fluid is put under pressure and flows through the outlet valve when open towards the dispenser orifice, the piston forming a closure wall that closes the dispenser orifice in the rest position, the closure wall positioned, in the rest position, over the dispenser orifice, the closure wall coming into leaktight contact with the inside surface of the dispensing wall;
the inside surface of the dispensing wall slopes, at the dispenser orifice, relative to the displacement axis X, and the closure wall of the piston slopes at an inclination that substantially corresponds to the inside surface of the dispensing wall.
10. The fluid dispenser member according to claim 9 , wherein the closure wall of the piston slopes at an inclination that substantially corresponds to the inside surface of the dispensing wall so as to create a cone-on-cone contact.