WO2021156574A1 - Oscillatory-rotary liquid dispensing device with spring, and associated method - Google Patents

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 housed 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 on the one hand allowing positions that allow fluidic communication between the emptying chamber and just one of said orifices and on the other hand 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 device according to the invention is characterized in that 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.

Description

OSCILLO-ROTATING LIQUID DISTRIBUTION DEVICE WITH

SPRING AND ITS METHOD

FIELD OF THE INVENTION The present invention relates to an oscillating-rotating volumetric sub-assembly and a device for volumetric pumping of a fluid.

STATE OF THE ART

The use of volumetric pumping devices for the delivery (injection, infusion, oral, spraying.) Of fluids and / or powder is known, in particular for medical, aesthetic, veterinary or food applications. In particular in the medical field, various mechanical or electromechanical systems are known such as sub-assemblies of the “syringe pump” type, “cartridge device shoots”, peristaltic pumps, piston pumps, rotary pumps. In the case of pumps actuated by a motor whether linear or rotary, when the fluid must be transferred at high speed and high pressure, that is to say greater than 4 bars, this implies the use of a motor capable of high speed operation and capable of delivering high force or torque.

In this field, we know the EPI application 803934 relating to a pump comprising a stator, a rotor comprising an axial extension sliding and rotating at least partially in a rotor chamber of the stator, and at least first and second valves between an inlet and a rotor chamber, respectively between the rotor chamber and an outlet, which open and close as a function of at least the angular displacement of the rotor. The pump includes interacting cam members on the rotor and stator and biasing means acting on the rotor to apply a force to the rotor in the axial direction of the stator cam member.

This prior art has represented an insufficient advance to reduce the size of rotary oscillating pump motors to be integrated into a portable device. Also known is patent EP3025058A1 which describes an oscillating-rotary sub-assembly for volumetric pumping of a fluid comprises a hollow body defining a cavity whose wall is crossed by two conduits, a piston defining with said cavity a working chamber and comprising a groove opening longitudinally into said working chamber, said piston being angularly movable to put said working chamber in fluid communication with one then none then the other of said ducts, and alternately in longitudinal translation so as to vary the volume of said working chamber and successively then discharge said fluid, said piston carrying a seal formed of at least one sealing ring, a sealing half-ring and at least one sealing tab longitudinally connecting said ring d sealing to said sealing half-torus.

Although this pump can be designed for small displacements and can withstand high pressures, it is necessary to use a very high engine speed when it is desired to deliver fluid quickly. In addition, to achieve this speed of rotation, the acceleration time of the engine is not negligible compared to the duration of ejection of the dose of fluid delivered by the pump. As a result, the rate of ejection is not constant throughout the dose. This results in relatively large motors to be integrated into a portable device.

Also known is patent EP2962714 which describes a micropump using an eccentric cam member rotating in a pump housing to sequentially open and close valves in the pump housing to remove fluid from a reservoir and deliver measured amounts of fluid to. a cannula port for administration to a patient. The micropump can be used in a disposable pump for continuous infusion of drugs such as insulin. The eccentric cam sequentially biases each valve actuator during a full rotation of the piston. This prior art has represented an insufficient advance for the impulsive administration of liquid with a motor of reduced size. In addition, the return force on the seals exerted by the valve springs must be high enough to ensure that the valve actuators do not open under the operating pressures of the micropump. Other examples of volumetric pumping devices for the delivery (injection, infusion, oral, spraying.) Of fluids and / or powder are also illustrated in documents DE202004018603, DE1936358, FR1416519, WO2015 / 011384, US1866217, US2005 / 132879, US4850824, FR940128 and FR1463091.

ABSTRACT

The present invention has been developed in order to solve the aforementioned problems, in particular the ability to ensure ejection of product at constant speed for a period which may be less than 100 ms while reducing the size of the rotary oscillating pump motors to reduce their bulk. and ensure the miniaturization of the final device. Indeed, the torque required to actuate a device of the type according to the invention is high and requires the use of an often bulky motor, with high energy consumption and thus limiting miniaturization.

The present invention therefore relates to a device for dispensing a product in liquid form comprising a fixed part and a movable part, the fixed part comprising a suction orifice, a discharge orifice, a body comprising a cavity into which said orifices open out, said cavity being able to partially receive the movable part, the volume formed between the surface of the cavity and the movable part defining an emptying chamber, the movable part being able to partially move 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 on the one hand positions allowing fluid communication between the emptying chamber and only one of said orifices and on the other hand, switching positions in which any fluid communication between the emptying chamber and each of said orifices is inter said, the device according to the invention comprising a cam capable of transforming the rotation of the drive element of the piston into oscillating-rotary movement of the piston, characterized in that the axial spring is capable of absorbing energy during a liquid suction phase and to restore it during a liquid delivery phase, said spring being positioned around the piston which is located on the movable part located in the body cavity. Preferably, the axial spring used in the present invention is a helical spring in order to help the motor by increasing the torque supplied during the delivery phase. Preferably, the helical spring can be withdrawn from the action of the motor. Advantageously, the helical spring allows ease of assembly. In the present invention, the duct extending along the circumference of the piston is delimited by sealing lips in order to ensure fluid tightness between the piston and the body of the device, as well as between the different zones of fluid circulation

Preferably, said duct comprises a discharge groove connecting the discharge orifice to the emptying chamber during the discharge phase and a suction groove connecting the suction orifice to the emptying chamber during the discharge phase. suction, said grooves being made in such a way as to place one of the suction or discharge ports in fluid communication with the emptying chamber or to prevent any fluid communication between said orifices and the emptying chamber during the discharge. rotation. In one embodiment of the invention, the suction groove is in the form of a helical internal thread forming an angle α preferably the same as the angle of the slope of the cam in order to reduce the dead volume.

Preferably, the discharge groove extends over an axis co linear with that of the cam stopper and forms with the longitudinal axis of the piston an angle b such as 0 ° <b <70 °, in order to optimize the operation of the device during the discharge stage.

Even more preferably, the angle b is an angle of 0 °.

In another embodiment, the suction port and the discharge port are angularly spaced apart by an angle of between 170 ° and 190 ° on a plane perpendicular to the longitudinal axis of the piston (22) to simplify the operation. design of the seal taking into account its optimal moldability. Preferably, the suction orifice and the delivery orifice are substantially at 180 ° with respect to each other on the same plane. The present invention also relates to a method of administering a fluid comprising four successive steps. During a first suction step, the device according to the invention is actuated to drive the rotation of the cam in order to obtain an oscillating-rotary movement of the piston, during said oscillating-rotary movement, the suction orifice is in position. communication with the duct and the discharge orifice is concealed so as to obtain the filling of the emptying chamber and the compression of the axial spring between the cam and a spring support. During a first intermediate step also called maximum switching step, following the suction step, the two suction and discharge ports are obscured and not communicating, and during which the drain chamber is in its maximum volume. During a third discharge step, the axial spring decompresses in order to cause the translation of the piston, to empty the discharge chamber through the discharge groove in fluid communication with the discharge orifice. During a second intermediate step also called minimum switching step, the two suction and discharge ports are concealed and not communicating and the piston is at the end of its stroke in the cavity of the body of the fixed part, and the axial spring is relaxed.

Preferably, the height of the stop of the cam is adjustable in order to vary the volume of liquid ejected from the drain chamber through the discharge port. This allows you to vary the amplitude and adjust the maximum volume. The present invention also relates to any medical device containing the device described above or using the liquid administration method described above.

The present invention also relates to a fluidic cassette comprising a fluidic circuit and a dispensing device according to the invention. DEFINITIONS

In the present invention, the terms below are defined as follows:

“Internal thread angle a” refers to the angle of inclination of the helical suction groove with respect to the piston axis. “Duct” indicates the path traveled by the liquid, it involves in the preferred embodiment a suction groove in the form of a helical internal thread and a discharge groove, the two grooves being located on the periphery of the piston

"Substantially" in the context of the invention means that one is within the margin of error corresponding to the accuracy of the value measuring tool.

"Fluid", in the invention, the fluid is a gas or a liquid, it is preferably a liquid.

“Cassette”: Removable case suitable for including a fluid distribution device.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is a longitudinal section of the device according to the invention in which the piston is at the end of its travel in the body cavity of the fixed part, the chamber is emptied and the axial spring is relaxed (minimum switching step).

FIG. 2 is a perspective view of the device according to the invention in which the piston is at the end of its stroke in the cavity of the body of the fixed part, the chamber is emptied and the axial spring is relaxed (minimum switching step) . The fixed part cam support is not shown.

Figure 3 is a longitudinal section of the entire body of the fixed part, the cam, the piston, the spring, the seal and the orifices when the piston is at the end of its stroke and the emptying chamber is emptied (minimum switching step).

Figure 4 is a front view of the cam, piston, seal and conduit assembly when the piston is at the end of its stroke and the drain chamber is emptied (minimum switching step).

FIG. 5 is a perspective view of the assembly illustrated in FIG. 4 in which the emptying chamber is filled with a liquid product. This figure is a perspective view of the cam, piston, seal and conduit assembly. Figures 7a, 7b, 7c and 7d illustrate the development of the cylindrical peripheral surface defined by the seal and the sealing lips. These four figures show the configurations of the suction and discharge ports as a function of the suction and discharge grooves during the four operating stages of the device.

Figure 6 is a longitudinal section of the device according to the invention in which the drain chamber is filled with liquid and the axial spring is compressed.

Figures 7e, 7f, 7g and 7h illustrate the development of the outer peripheral surface of the cam. These four figures show the configurations of the cam as a function of the cam support during the four stages of operation of the device.

FIGS. 8a to 8d are front views of the assembly comprising the end of the piston and the seal, illustrating four different configurations of the assembly during a complete rotation of the movable part, in which the orifice of discharge is shown in projected view. Figures 8e to 8h are front views of the assembly comprising the end of the piston and the seal which show the side opposite to that illustrated in Figures 8a to 8d respectively and in which the suction port is shown in projected view.

DETAILED DESCRIPTION The present invention relates to a device for dispensing liquid product and it will be better understood on reading the following figures which are an illustration without limiting the invention.

As detailed in Figure 1, the body 13 of the fixed part 1 is hollow and comprises at least two cylindrical cavities 151, 152 of longitudinal axis (A) and of different diameters, interconnected by a shoulder 18 and communicating with each other. thus defining the cavity 15 adapted to receive the movable part 2. The cylindrical cavity 152 of large diameter communicates with the outside as well as with the cylindrical cavity of small diameter 151, this cavity is configured to partially receive a support for spring 16 and to fully receive the coil spring 23 and the cam 25. It should be noted that the turns of the coil spring 23 are wound around the movable part 2, this spring rests on the support of the spring 16 which forces it during of the suction phase. The relaxation of the spring 23 makes it possible to bring additional energy to the engine to move the piston 22 in order to empty the emptying chamber 27.

As visible in Figure 1, the spring 23 is positioned around the piston 22. Having the spring around the piston 22 provides enhanced stability to the device. Indeed, depending on the size and stiffness of the spring 23 chosen, it is possible that a phenomenon of buckling of the spring 23 is observed during its compression. Centering around piston 22 avoids this problem. Advantageously, this configuration also allows simplicity of assembly and greater compactness by capitalizing on the presence of the bearing surface between the support of the spring 16 (pump body) and the piston 22. The centering of the spring 23 around the piston 22 still has other advantages such as the placement and the centering of the means for reducing the frictional forces between the spring 23 and the bearing surfaces. In general, the centering of the spring 23 in the axial position allows a better distribution of the mechanical stresses on the piston 22.

In a preferred embodiment, the relaxation of the spring makes it possible to provide the energy necessary to move the piston in order to empty the emptying chamber 27. This makes it possible in FIG. 1 to move the piston 22 and empty the emptying chamber 27. This allows to reduce the necessary torque of the latter and therefore to reduce its size or even its bulk.

In addition, the cam 25 comprises an inclined ramp 251 able to slide on a cam support 14 of the fixed part 1. The small diameter cylindrical cavity 151 has an end communicating with the large diameter cylindrical cavity 152 and a closed end. The cylindrical cavity 151 is intended to partially receive the piston 22. The seal between the piston and the cylindrical cavity of small diameter 151 is provided by the seal of the piston 29. The cylindrical cavity 152 may for example have a variable diameter. to fit the spring support 16 and the piston drive element 21. Referring to Figure 2, the drive element of the piston 21 is a cylinder of longitudinal axis A of a shape adapted to receive an engine comprising for example a flat and a cylindrical cavity, it is linked to the movable part 2 via a connection means 30, said connection means 30 can be of any shape complementary to the corresponding recess in the piston 22, a flat or cross shape can be envisaged for example. The piston driving element 21 is suitable for being driven by a motor in a preferential manner, but any other means of supplying mechanical energy can be envisaged. It is specified that this element is preferably driven by a motor but any other means of supplying mechanical energy can be envisaged knowing that the presence of the axial spring will make it possible to reduce the required energy input. This on condition that the means of supplying energy is sufficiently impulsive.

Referring to Figure 3, the seal 29 and the duct 24 are made so as to place alternately, that is to say successively one then the other with the possibility of intermediate steps, in fluid communication one of the suction or discharge ports 11, 12 respectively with the emptying chamber or to prevent any communication between the suction or discharge ports 11, 12 respectively and the emptying chamber 27. In the example illustrated in FIG. 3, the discharge port 12 is in fluid communication with the emptying chamber 27. Communication between the emptying chamber 27 and the suction port 11 is prohibited. More particularly, the configuration of the duct 24 (visible in FIG. 4) and of the seal 29 allows fluid communication between one of the suction or discharge ports 11, 12 with the emptying chamber during the stages of suction and discharge, this is illustrated by Figures 7a and 7c respectively. This configuration according to the invention prohibits any fluid communication between the suction or discharge ports 11, 12, respectively, and the emptying chamber 27 during the intermediate stages also called switching stages, illustrated by FIGS. 7b and 7d.

As illustrated by Figures 1 to 3, the cavity 15 is placed in fluid communication, with an upstream fluidic circuit and a downstream fluidic circuit, with the outside via the suction and delivery orifices 11, 12 opening onto the external surface. body 13 and having an axis of symmetry perpendicular to the axis A. Each of the two suction and discharge ports, respectively 11, 12, has a cylindrical part of small diameter opening inside the cylindrical cavity 151 and a further part large diameter opening to the outside of the body 13. In the example illustrated, the large diameter part of the discharge orifice 12 thus has the shape of a truncated cone and the small diameter part of the orifice of suction 11 has the shape of a cylinder. The axis of the suction port 11 and the axis of the discharge port 12 can be offset longitudinally with respect to the axis A and angularly in a plane perpendicular to the axis A. In the example illustrated in Figures 1 to 3 the suction and discharge ports 11, 12 are offset longitudinally with respect to the axis A and are offset from one another by an angle of 180 ° along a plane perpendicular to the axis A. In an alternative embodiment (not illustrated), the two suction and discharge ports 11, 12 are angularly offset from one another by an angle of 0 °. In another alternative embodiment, they are not offset from each other longitudinally. As detailed in Figure 4, the piston 22 has a diameter slightly less than the diameter of the cylindrical cavity 151 and the seal between the piston 22 and the body of the fixed part 1 is ensured by the compression of the seal 29 positioned. on the end of the piston 22. In particular, the seal 29 has a generally cylindrical shape, the inner surface of said seal is in intimate contact with the outer surface of the piston 22 and the outer surface of said seal is provided with lips of Sealing 26 intended to be compressed against the surface of the cylindrical cavity 151 in order to provide fluid sealing of the duct and of the chamber.

As illustrated in Figures 4 and 5, said sealing lips 26 define several channels having different depths, namely at least a first channel, one end of which opens into the emptying chamber 27, at least a second channel in fluid connection with said first channel and additional non-communicating channels not communicating with the emptying chamber 27 and preferably having a depth less than that of the first and of the second channel, in order to minimize the dead volumes. As illustrated in Figure 4, the first channel opening into the emptying chamber 27 corresponds to the discharge groove 241, the second channel in fluid connection with said first channel corresponds to the suction groove 242 and said first channel and second channel form a duct 24 on the circumference of the seal.

It should be noted that the duct 24 is arranged entirely on the circumference of the seal, and in particular does not contain any portion inside the piston 22. As illustrated in FIG. 4 and in FIGS. 7a to 7d, the lips of sealing 26 also define additional non-communicating channels having a depth less than that of the delivery and suction grooves and which extend around the seal 29 so as to be opposite one of the suction openings 11 or discharge 12 when the other orifice 12,11 is located opposite a delivery groove 241 or suction 242 of the duct 24 or opposite another additional channel.

More particularly, during an operating step of the device illustrated in FIG. 7a, the suction port 11 is located opposite the suction groove 242 and the discharge port 12 is located in one of said additional channels not communicating with the emptying chamber 27. In a second operating step illustrated by FIG. 7b, the two suction 11 and discharge 12 orifices are located in additional channels not communicating with the emptying chamber 27. In a third operating step of the device shown in FIG. 7c, the delivery orifice 12 is located opposite the delivery groove 241 and the suction orifice 11 is located in an additional channel not communicating with the emptying chamber 27. Advantageously, the width of the delivery grooves 241 and of the suction is appreciably greater than the diameter of the suction and delivery openings 242. In FIG. 7d, as in 7c, an orif ice is hidden and the other is in groove 241.

The duct 24 included on the seal 29 and delimited by the sealing lips 26 comprises a discharge groove 241 forming an angle b of between 0 ° and 70 ° with the axis A and a suction groove 242 by example in the form of a helical internal thread forming an angle a with respect to the axis A. The angle b is defined in figure 4, and preferably, an angle of 0 ° and the angle a is identical to the angle of the slope of the cam 25. In this configuration (illustrated in FIG. 4), the discharge groove 241 is parallel to the axis A and extends in a direction included in the collinear plane of the cam stopper 28. In an alternative embodiment not shown, the discharge groove 241 and the cam stopper 28 form an angle b with the axis A of between 0 ° and 70 ° while being different from 0 °. Preferably, the discharge groove 241 extends in a direction parallel to that of extension of the cam stopper 28. In this case, the spring makes it possible to provide additional energy to the motor.

Referring to Figure 5, the position of the free end of the piston 22 in the cavity 151 defines a drain chamber 27 of cylindrical shape and variable volume. The volume of the emptying chamber 27 is defined by the internal volume of the cavity 151, going from the closed end of said cavity to the flat circular surface which belongs to the free end of the piston 22. When the piston 22 is in its low position, the spring 23 is compressed, the emptying chamber 27 is at its maximum volume (configuration visible in Figures 5 and 6) while when the piston 22 is in a high position, the spring in its relaxed position since returned to its initial position of reduced stress, the drain chamber is at its minimum volume (configuration visible in FIGS. 1 to 4), the liquid has been expelled.

As detailed in Figures 1, 4 and 5, the cam 25 comprises an inclined ramp 251 (Fig. 4 and 5) able to slide on a cam support 14 (Fig. 1) and a cam stop 28 in the form of a. a step comprising a radial surface with respect to the axis A and delimited by two parallel sides 281 and 282 in common with the inclined ramp 251 of the cam 25. With particular reference to FIGS. 4 and 5, the side 281 connects the stop of cam 28 to an upper part of the inclined ramp 251 and the side 282 connects the cam stopper 28 to a lower part of the inclined ramp 251. In practice, each side 281, 282 is the edge of a dihedral angle formed by meeting the cam stopper 28 with the inclined ramp 251.

It should be noted that the seal 29 can for example be manufactured by overmolding on the piston 22 or manufactured independently of the piston and assembled thereon. The seal 29 is positioned around the end of the piston 22 able to move in the cavity 151. As illustrated in Figures 7e, 7f, 7g and 7h, the upper part and the lower part defining the start and the end of the inclined ramp 251 are perpendicular to the axis A. Consequently, the dihedral angle formed by the meeting of the cam stopper 28 with the upper part or the lower part of the inclined ramp 251 is a right angle of 90 °. Reversal of the direction of rotation of the movable part is prevented by the presence of the cam stopper 28. In an alternative embodiment not shown, the cam stopper 28 has a surface which is not radial to the axis of the piston and connects the upper part to the lower part of the inclined ramp 251 with an angle relative to the axis of the piston differ by 90 °. In this alternative embodiment, the discharge groove 241 is inclined relative to the axis of the piston with an angle b between 0 ° (excluded) and 70 ° while being identical to the angle formed by the cam stopper 28 and said axis.

Figures 7a to 7d illustrate the development of the lateral surface of the cylinder defined by the seal 29; the small diameter parts of the suction and discharge ports 11 and 12 are shown in a projected view on a plan. Figures 7e to 7h illustrate the development of the outer surface of the cam 25; the cam support 14 is shown in a projected view on a plan. For the sake of simplicity and to make the diagram easier to understand, a simplified representation of the cam support 14 is shown.

The mode of operation of the device according to the preferred mode is as follows: During the suction step, a motor drives the almost complete rotation of the cam 25 in order to obtain an oscillating-rotary movement of the piston 22 in the cavity 15; during the tilt-and-turn movement, the piston 22 passes from a high position in which the drain chamber has a minimum volume of liquid (Figures 1 to 3) to a low position (Figure 5) in which the drain chamber 27 is filled with liquid. The step defined by the cam stopper 28 may alternatively have an adjustable position via a pin capable of transmitting kinetic energy to the piston. Between the start of the suction step and the end of the delivery step, the cam 25 has performed a complete rotation of 360 °. The impulsive decompression of the axial spring 23 during the discharge step causes the translation of the piston 22 from a low position (figures 5 and 6) in which the drain chamber 27 is adapted to be filled with liquid to a high position (figure 1 to 4) in which the emptying chamber 27 is adapted to be emptied of liquid. As illustrated in FIG. 7c, during the discharge step, the suction port 11 is hidden in an additional channel not communicating with the emptying chamber 27 and the discharge port 12 is in fluid communication with a discharge groove 241. longitudinal to axis A or oblique at an angle b of between 0 ° and 70 °; in the example illustrated in Figures 7a to 7d and in Figures 8a to 8d, the angle b is an angle of 0 °. FIGS. 8a, 8b, 8g, 8h illustrate examples of configurations in which the suction orifice 11 or the discharge orifice 12 is concealed in an additional channel not communicating with the emptying chamber. It should be noted that the additional non-communicating channels are exclusively dedicated to sealing and blocking the suction orifice 11 or the discharge orifice 12 during intermediate steps also called minimum and maximum switching steps.

REFERENCED NUMBERS

1: fixed part 11: suction port

12: discharge port

13: body

14: cam support

15: cavity 151, 152: cylindrical cavities

16: spring support 18: shoulder

2: moving part

21: piston drive element 22: piston 23: axial spring

24: led

241: discharge groove

242: suction groove 25: cam

251: inclined ramp

26: sealing lips

27: drain chamber

28: cam stopper 281, 282: cam stopper sides

29: seal

30: connection means A: piston pin

D: device a: angle of inclination of the helical suction groove with respect to the longitudinal axis of the piston. b: angle of inclination of the discharge groove relative to the longitudinal axis of the piston

Claims

1. Device for dispensing (D) product in liquid form comprising a fixed part (1) and a movable part (2), • the fixed part (1) comprising: o a suction orifice (11) and a delivery orifice (12), o a body (13) comprising a cavity (15), o into which the said orifices (11, 12) open. ), said cavity (15) being able to partially receive the movable part (2), the volume formed between the surface of the cavity (15) and the movable part (2) defining a drain chamber (27), • the movable part (2) able to move partially in the cavity (15) of the fixed part (1) comprising: o a piston (22), o a piston drive element (21), o an axial spring (23), o a duct (24) extending along the circumference of the piston (22), such that said duct (24) allows on the one hand positions allowing fluid communication between the emptying chamber (27) and only one of said orifices (11, 12) and on the other hand of the switching positions in which any fluid communication between the emptying chamber (27) and each of said orifices (11, 12) is prohibited, the device (D) comprising a cam (25) capable of transforming the rotation of the driving element of the piston (21) into oscillating-rotary movement of the piston (22), characterized in that the axial spring (23) is capable of absorbing energy during a liquid suction phase and to restore it during a liquid delivery phase, said spring being positioned around the piston one (22) which is located on the movable part (2) located in the cavity (15) of the body (13). 2. Device according to claim 1, wherein the axial spring (23) is a helical spring. 3. Device according to any one of claims 1 or 2, wherein the duct (24) is delimited by sealing lips (26) in order to ensure fluid tightness between the piston (22) and the body ( 13) of the device. 4. Device according to any one of claims 1 to 3, wherein the duct (24) comprises a discharge groove (241) connecting the discharge port (12) to the drain chamber (27) during the phase discharge, and a suction groove (242) connecting the suction port (11) to the emptying chamber (27) during the suction phase. 5. Device according to claim 4, wherein the suction groove (242) is in the form of a helical internal thread forming an angle a preferably identical to the angle of the slope of the cam (25). 6. Device according to any one of claims 4 or 5, wherein the discharge groove (241) extends on an axis collinear with that of the cam stopper 28 and forms with the longitudinal axis of the piston (22) an angle b such that 0 ° <b <70 °. 7. Device according to claim 6, wherein the angle b is preferably an angle of 0 °. 8. Device according to any one of claims 1 to 7, wherein the suction port (11) and the discharge port (12) are angularly spaced at an angle of between 170 ° and 190 ° over a plane perpendicular to the longitudinal axis of the piston (22). 9. A method of administering a fluid using a device (D) according to any one of claims 1 to 8, comprising the following four successive steps: a. A suction step, during which the device (D) is actuated to drive the rotation of said cam (25), in order to obtain an oscillating-rotary movement of the piston, during said oscillating-rotary movement, the orifice suction (11) is in communication with the duct (24) and the delivery orifice (12) is concealed so as to obtain the filling of a drain chamber (27) and the compression of the axial spring (23) between the cam (25) and a spring support (16), b. A first intermediate step, during which the two suction (11) and discharge (12) orifices are obscured and not communicating, and during which the emptying chamber is in its maximum volume, c. A discharge step, during which the axial spring (23) decompresses in order to cause the translation of the piston (22), to empty the discharge chamber (27) through the first discharge groove (241) in fluid communication with the 'discharge port (12), d. A second intermediate step, during which the two suction (11) and delivery (12) ports are concealed and not communicating, the piston (22) is at the end of its travel in the cavity (15) of the body of the part. fixed (1), and the axial spring (23) is relaxed. 10. A method of administering a liquid using a device (D) according to any one of claims 1 to 8, wherein the height of the stopper (28) of the cam (25) is adjustable in order to vary the volume. of liquid ejected from the drain chamber (27) through the discharge port (12). 11. A medical apparatus containing the device (D) according to any one of claims 1 to 8 or using a method of administering a fluid according to any one of claims 9 or 10. 12. Fluidic cassette comprising a fluidic circuit and a distribution device (D) according to one of claims 1 to 8.