Oscillatory-rotary liquid dispensing device with spring, and associated method

Abstract

The present invention relates to a device for dispensing liquid product, comprising a fixed part and a moving part; the fixed part comprising an intake orifice, a delivery orifice, a body comprising a cavity into which said orifices open, said cavity being able to partially house the moving part, the remaining volume forming an emptying chamber; the moving part being able to move partially in the cavity of the fixed part and comprising a piston, a piston driving element, an axial spring, a duct extending along the circumference of the piston, said duct allowing positions that allow fluidic communication between the emptying chamber and just one of said orifices and allowing switchover positions in which all fluidic communication between the emptying chamber and each of said orifices is forbidden, a cam able to convert the rotation of the drive element into an oscillatory-rotary movement of the piston. The axial spring is able to absorb energy during a liquid intake phase and to restore same during a liquid delivery phase, said spring being positioned around the piston which is on the moving part situated inside the cavity of the body.

1 . A device for dispensing product in liquid form, comprising a fixed part and a moving part,
 the fixed part including: 
 an intake orifice and a delivery orifice, 
 a body comprising a cavity, 
 into which said orifices open, 
 said cavity being able to partially house the moving part, the volume formed between the surface of the cavity and the moving part defining an emptying chamber, 
 
   the moving part able to partially move in the cavity of the fixed part, including: 
 a piston, 
 a piston driving element, 
 an axial spring, 
 a duct extending along the circumference of the piston, such that said duct allows positions that allow fluidic communication between the emptying chamber and just one of said orifices and allows switchover positions in which all fluidic communication between the emptying chamber and each of said orifices is forbidden, 
   the device including a cam able to convert the rotation of the piston driving element into an oscillatory-rotary movement of the piston,   wherein the axial spring is able to absorb energy during a liquid intake phase and to restore same during a liquid delivery phase, said spring being positioned around the piston which is on the moving part situated in the cavity of the body.   
     
     
         2 . The device according to  claim 1 , wherein the axial spring is a helical spring. 
     
     
         3 . The device according to  claim 1 , wherein the duct is delimited by sealing lips in order to ensure the fluid-tightness between the piston and the body of the device. 
     
     
         4 . The device according to  claim 1 , wherein the duct includes a delivery groove connecting the delivery orifice to the emptying chamber during the delivery phase, and an intake groove connecting the intake orifice to the emptying chamber during the intake phase. 
     
     
         5 . The device according to  claim 4 , wherein the intake groove is in the form of a helical internal threading forming an angle α preferably identical to the angle of the slope of the cam. 
     
     
         6 . The device according to  claim 4 , wherein the delivery groove extends on an axis co-linear with that of the cam abutment and forms with the longitudinal axis of the piston an angle β such that 0° ≤ β ≤ 70°. 
     
     
         7 . The device according to  claim 6 , wherein the angle β is preferably an angle of 0°. 
     
     
         8 . The device according to  claim 1 , wherein the intake orifice and the delivery orifice are angularly separated by an angle between 170° and 190° on a plane perpendicular to the longitudinal axis of the piston. 
     
     
         9 . A method for administering a fluid using a device according to  claim 1 , including the following four successive steps:
 a. An intake step, during which the device is actuated to drive the rotation of said cam, in order to obtain an oscillatory-rotary movement of the piston; during said oscillatory-rotary movement, the intake orifice is in communication with the duct and the delivery orifice is covered so as to obtain the filling of an emptying chamber and the compression of the axial spring between the cam and a spring support,   b. A first intermediate step, during which the two orifices, the intake orifice and delivery orifice, are covered and non-communicating, and during which the emptying chamber is at its maximum volume,   c. A delivery step, during which the axial spring is decompressed in order to bring about the translation of the piston, in order to empty the emptying chamber through the first delivery groove in fluidic communication with the delivery orifice,   d. A second intermediate step, during which the two orifices, the intake orifice and the delivery orifice, are covered and non-communicating, the piston is at the end of the stroke in the cavity of the body of the fixed part, and the axial spring is released.   
     
     
         10 . The method according to  claim 9 , wherein the height of the abutment of the cam is adjustable in order to vary the liquid volume ejected from the emptying chamber through the delivery orifice. 
     
     
         11 . A medical apparatus containing the device according to  claim 1 . 
     
     
         12 . A fluid cartridge including a fluid circuit and a dispensing device according to  claim 1 . 
     
     
         13 . A method for administering a fluid using a medical apparatus containing the device according to  claim 1 .