Precision piston pump device

Abstract

The present invention relates to a piston pump (1) comprising a piston guide (3) arranged at its end (10b), which piston guide is provided with an orifice (30) of a diameter corresponding to the stem diameter (D200) of the piston (20) and a wedging device (32) adapted to centre the piston guide (3) on the pump body (10), a kit comprising several pistons and piston guides mountable on the pump, and a method for pumping a liquid by means of such a piston pump.

Description

Precision piston pump device Technical field

[0001] The present invention relates to a precision piston pump, in particular for collecting biological samples. The present invention relates more particularly to a modular pump, in particular allowing the piston to be replaced. The present invention further relates to a kit or assembly comprising such a pump and several pistons. The present invention further relates to a method of pumping or dosing using such a pump. State of the art

[0002] Piston pumps are used for precision applications, particularly in the medical and research fields. They allow precise quantities of liquid to be pumped for treatment, sampling, dosing, or diagnostic purposes. They must therefore be highly accurate and reliable under the conditions of use. The principle is based on the use of a rotary motor, which can be stepper or direct current, whose alternating rotational movement is converted into a translational movement of the piston to pump the liquid.

[0003] Such pumps suffer from a lack of flexibility in their use. In this case, a given pump is often defined for a given application. Multiple pumps must then be used when different ranges of liquid quantities need to be handled, or when several applications are implemented, which significantly increases operating costs.

[0004] In addition, their maintenance operations, which guarantee their reliability, immobilize them, which generates difficulties and costs. management. When breakdowns occur unexpectedly, the consequences can also be dramatic.

[0005] There is therefore room for improving existing pumps, particularly to allow greater flexibility of use without losing their reliability or precision.

[0006] Brief summary of the invention

[0007] An object of the present invention is to provide a precision piston pump whose use is permitted over a wider range of volumes and / or pumping flow rates and / or types of applications. In particular, it is a question of providing a piston pump compatible with several sizes or types of pistons.

[0008] Another aim of the invention is to provide a piston pump that is easier to maintain or requires fewer maintenance operations.

[0009] Another object of the present invention is to provide a method of metering and / or pumping a liquid over a wide range of volumes or pumping rates.

[0010] According to the invention, these aims are achieved in particular by means of the invention, in particular the aspects and embodiments described below.

[0011] In particular, the present piston pump comprises a pump body. The pump body preferably has first and second ends oriented along a longitudinal axis X. The pump body further comprises a piston adapted to move in translation along the longitudinal axis. The piston may comprise a piston rod, having a rod diameter, and a piston base. The piston base is provided with a piston housing.

[0012] The present piston pump further comprises a pump base fixed to a first end of the pump body. The pump base comprises a motor adapted to rotate a drive shaft along the longitudinal axis. The drive shaft preferably comprises at least one thread.

[0013] The present piston pump further comprises a transmission system connecting the drive shaft to the piston, so that a rotational movement of the drive shaft produces a translational movement of the piston.

[0014] This piston pump may include an anti-rotation device for blocking the rotation of the piston during rotation of the drive shaft.

[0015] This piston pump comprises a pump head comprising a liquid inlet to be pumped, an internal chamber and a liquid outlet. The internal chamber is in communication with the piston rod. The pump head is associated with the second end of the pump body.

[0016] The present piston pump preferably comprises a piston guide disposed at the second end of the pump body. The piston guide comprises an orifice with a diameter corresponding to the diameter of the piston rod. It further comprises a wedging device adapted to center the piston guide on the pump body.

[0017] The pump head preferably includes a fastening device cooperating with the pump body. The piston guide may include one or more assembly points compatible with the pump head fastening device. It can thus be fixed to the pump body by means of the pump head fastening device.

[0018] The pump body preferably comprises a lateral opening. It may further comprise a control board obscuring the lateral opening. The control board may comprise, preferably on its internal surface, at least one position detector, such as a first and / or a second detector. The piston advantageously comprises a position index identifiable by the position detector(s).

[0019] The control board may have one or more connectors and / or electronic components on its external surface.

[0020] The piston anti-rotation device preferably comprises a groove arranged on the circumference of the piston base and oriented along the longitudinal axis, and a lip or lug arranged on the internal surface of the pump body. The lip or lug cooperates with the groove to block the piston's rotation while allowing its translation.

[0021] The transmission system may comprise a first drive nut threaded in its center and in contact with the piston base. The first drive nut is arranged on the thread of the drive shaft, for example at the drive zone, so as to move the piston in translation during rotation of the drive shaft.

[0022] The transmission system may include a second drive nut threaded at its center and disposed on the thread of the drive shaft, for example at the drive zone. It may further include a spring disposed between the first and second drive nuts.

[0023] The drive shaft preferably comprises a first threaded portion disposed at its first end. It can thus cooperate with a shaft attachment on the base of the pump. It may comprise an intermediate portion adapted to cooperate with the motor. It further comprises a drive zone cooperating with the transmission system. Its second end is preferably housed in the piston housing. The second end of the drive shaft can thus form with the piston housing a reservoir suitable for receiving lubricant.

[0024] The present pump may comprise or be connected to one or more sensors among a temperature sensor, an ultrasonic sensor, a vibration sensor, a pressure sensor, an ambient temperature sensor, an atmospheric pressure sensor, a hygrometry sensor, an electrical consumption sensor.

[0025] This pump may include or be connected to a module for processing the data collected by the one or more sensors and / or one or more artificial intelligence programs suitable for analyzing the data collected.

[0026] The kit of the present description comprises a pump according to the present description and one or more additional pistons having rods of different diameters.

[0027] This kit may further include one or more additional piston guides all having the same assembly points and holes of different diameters, each corresponding to the rod diameters of said additional pistons.

[0028] In this kit, the bases of the additional pistons can all be identical.

[0029] The method of pumping, metering or dispensing a liquid according to the present description is operated by means of a pump as described herein. It comprises activating the motor to alternately rotate the drive shaft by a given angular value in one direction of rotation and then in the opposite direction so as to move the piston in translation along the longitudinal axis between a first and a second end-of-travel position.

[0030] The present method may comprise a step of replacing the piston with another piston whose rod has a different diameter while retaining the pump body.

[0031] The present method may comprise a step of considering one or more environmental parameters and / or one or more operating parameters of the pump and adapting the motor pitch and / or predicting an event among a breakdown, a maintenance operation or the end of life of the pump.

[0032] The present method may further comprise a step of automatically lubricating the drive shaft.

[0033] This solution offers a significant advantage over previous methods by improving the flexibility and / or modularity of precision pumps without compromising reliability or accuracy. Furthermore, it allows for better-planned and / or less frequent maintenance operations.

[0034] This solution also guarantees optimal operating mode and therefore increased reliability of pumping or dosing results. Brief description of the figures

[0035] Examples of implementation of the invention are indicated in the description illustrated by the following figures: • [Fig.1]: Schematic perspective representation of a pump according to an embodiment of the present invention, [Fig.2]: Cross-sectional representation of a pump according to an embodiment of the present invention, • [Fig.3a]: Exploded perspective view of a piston and piston guide assembly according to an embodiment of the present invention, • [Fig.3b]: Perspective representation of a pump body without piston according to an embodiment of the present invention, • [Fig.4]: Perspective representation of a pump body with piston according to an embodiment of the present invention, • [Fig.5]: Cross-sectional representation of a detail of a pump according to an embodiment of the present invention, • [Fig.6]: Perspective representation of the drive shaft according to an embodiment of the present invention. Example(s) of embodiment of the invention

[0036] With reference to Figure 1, the pump 1 according to the present description comprises a pump body 10 acting as a casing or frame. The pump body 10 has an elongated shape along a longitudinal axis X. Its general shape may be generally cylindrical without being limited thereto. It may for example be of rectangular or square or hexagonal section. The pump body 10 is hollowed out and has openings at each of its first 10a and second 10b ends. A piston 20 is housed in the pump body 10 so as to move therein in translation along its longitudinal axis X. The piston 20 comprises a piston rod 200 and a piston body 201. The piston rod has a rod diameter D200 adapted to the expected performance of the pump, in particular in terms of pumping flow rates. A first opening, forming a piston passage 100 (fig.3b) allows the passage of the piston rod 200.

[0037] The piston body 201 has a larger diameter than the rod diameter D200. The piston body 201 and the rod 200 can be made from a single piece or from two assembled pieces. The material of the rod 200 can be the same as or different from that of the piston body 201. Thus, the material of the rod and / or the piston body can be independently adapted to the requirements, taking into account aspects such as chemical compatibility, production costs, mechanical reliability, etc.

[0038] The piston body 201 comprises a piston housing 204 forming an opening on its face opposite the rod 200 and in the axis of the rod 200. The piston housing may take the form of a hole drilled in the body of the piston 201 along the longitudinal axis X. The dimensions of the piston housing are adapted to receive a drive shaft 112.

[0039] The pump described here comprises a base 11 fixed to the first end 10a of the pump body 10. The base 11 and the pump body 10 can be assembled by any suitable means, preferably allowing their disassembly. The base 11 can for example be bolted or screwed into the pump body 10. The base comprises a motor 110 for driving a drive shaft 112 in rotation about the longitudinal axis X. The motor is powered by a power connection 111. The drive shaft 112 is rotatably fixed to the base 11 by its first end 112a by means of a shaft attachment 113. Such a shaft attachment comprises for example a ball bearing or any equivalent device for holding the shaft in position while allowing its rotation. The second end of the drive shaft 112b is disposed in the piston housing 204.To do this, the drive shaft 112 passes through the opening disposed at the first end of the pump body 10a. The drive shaft 112 comprises a thread 114 over at least a portion of its length. The circumference of the shaft. drive may be for example threaded on the portion included in the pump body 10, or a fraction of this portion.

[0040] The motor allows the drive shaft 112 to rotate by a determined angular distance, in both directions of rotation. The stroke of the piston depends on the angular distance traveled by the drive shaft 112 under the effect of the steps of the motor. The motor may be of the stepping or direct current type or of any other type suitable for alternating rotation of the drive shaft.

[0041] The pump 1 comprises a transmission system 4, making it possible to transmit the mechanical movements of the drive shaft 112 to the piston 20. The transmission system 4 comprises at least one drive nut 41, 42, in contact with the base 201 of the piston 20. Such a drive nut may take the form of a ring whose center is threaded so as to cooperate with the thread 114 of the drive shaft 112. A rotation of the drive shaft 112 makes it possible to move the drive nut in translation along the longitudinal axis X thanks to the cooperation of the corresponding threads. A first drive nut 41 may be arranged around the drive shaft 112, in contact with the base of the piston so as to transmit to the piston 20 its translational movement during the rotation of the drive shaft 112.The first drive nut 41 is arranged at the inlet of the piston housing 204 so as to leave at the second end 112b of the drive shaft the clearance necessary for the translation of the piston. The first drive nut 41 can be associated with the base 201 of the piston by any suitable means. According to one embodiment, the first drive nut 41 comprises a neck 410 capable of being fitted into the piston housing 204. It thus makes it possible to precisely center and position the drive shaft 112 and the base of the piston 201 relative to each other and to push and pull the piston according to the direction of rotation of the drive shaft 112. It can also be easily separated from the piston, in particular for maintenance or replacement operations of the piston 20.

[0042] The second end 112b of the drive shaft 112 moves in the piston housing 204 during rotation of the drive shaft 112. In particular, the second end 112b of the drive shaft 112 approaches the bottom of the piston housing 204 or moves away from it depending on its direction of rotation.

[0043] The transmission system 4 may include a second drive nut 42 associated with a spring 43 to compensate for any operating backlash. The second drive nut 42 has a thread in its center to engage with the thread of the drive shaft. The spring 43 is positioned between the first 41 and the second 42 drive nuts.

[0044] The first end 10a of the pump body may further comprise a centering device 115 making it possible to maintain the drive shaft 112 in the longitudinal axis X.

[0045] The pump according to the present description further comprises a pump head 12, arranged at the second end 10b of the pump body 10. The pump head 12 allows the circulation of the liquid L to be pumped. For this purpose, it comprises a liquid inlet 120, a liquid outlet 122 and a chamber 121 in fluid connection with the inlet 120 and the outlet 122. The liquid inlet 120 is preferably arranged laterally with respect to the longitudinal axis X and the liquid outlet is arranged along the longitudinal axis X. The end 200a of the rod 200 of the piston 20 is included in the chamber 121 so that the alternating translational movements of the piston 20 along the longitudinal axis X make it possible to suck the liquid L into the chamber 121 when it is withdrawn and to push it through the outlet 122 when it is advanced into the chamber 121. The chamber is internal to the pump head 12.The pump head 12 is fixed to the second end 10b of the pump body 10 by a suitable fixing device such as a set of screws or bolts or any equivalent. One or more intermediate parts may be used, such as a piston guide 3 described later, in particular to allow the centering of the pump head 12 relative to the axis of. translation of the piston. One or more seals 123 may be arranged around the piston rod 200 and / or at the interface between the pump head 12 and the pump body 10.

[0046] The pump head may have several inlets 120 and / or outlets 122. It may be designated by the terms collector or “manifold” in English.

[0047] The pump according to the present description is characterized by the presence of a piston guide 3 (Figure 3a) arranged at the second end 10b of the pump body 10, making it possible to maintain the rod 200 of the piston in the longitudinal axis X. For this purpose, the piston guide 3 comprises an orifice 30 whose diameter corresponds to the diameter D200 of the rod 200 of the piston 20. The piston guide 3 comprises around its orifice 30 a bearing surface 31 coming to bear on the end of the pump body 10. It further comprises a wedging means 32, making it possible to maintain the orifice 30 centered on the longitudinal axis X. Such a wedging means 32 may comprise for example a lip or lugs adapted to come to bear on the internal surface of the pump body 10. The piston guide 3 may further comprise assembly points 33 adapted to keep it fixed to the pump body 10. Such points Assembly components may include one or more screws or bolts.According to one embodiment, the assembly points are compatible with the attachment means of the pump head 12 so that the piston guide can be assembled or removed concomitantly with the pump head 12. Thus, the assembly points can be reduced to holes in the bearing surface through which screws or bolts can pass. The holes corresponding to the assembly points 33 then coincide with the screws or bolts making it possible to fix the pump head 12 on the pump body 10. According to a preferred embodiment, the bearing surface of the piston guide 3 is inserted between the pump head 12 and the pump body 10. Preferably, the device for fixing the pump head 12 is compatible with the assembly points 33 of the piston guide 3, so that the device for fixing the pump head 12 also allows the piston guide 3 to be fixed on the pump body 10.

[0048] Other alternatives may be used to secure the piston guide 3 to the pump body 10. For example, the shim 32 of the piston guide 3 may be provided with an external thread and the pump body 10 may have an internal thread at its second end 10b so that the piston guide can be screwed onto the pump body 10.

[0049] The piston guide 3 also acts as a centering element for the pump head 12 relative to the pump body 10 and the piston rod 200.

[0050] According to an advantageous aspect of the present invention, the piston guide 3 can be easily separated from the pump body 10, for example by unscrewing the corresponding screws or bolts, or by unscrewing the piston guide itself if necessary. This allows easy access to the interior of the pump body 10. For this purpose, the diameter D of the opening allowing the passage of the piston 100, at the second end 10b of the pump body 10, can be at least equal to the diameter of the base 201 of the piston so that the piston can be removed or replaced with minimal effort. Under these conditions, it is sufficient to dissociate the piston guide 3 from the pump body 10 to directly access the piston 20. The diameter D' of the wedging means 32 is then equal to the diameter D of the piston passage 100. As a result, the piston passage 100 is wider than the diameter D200 of the rod 200 of the piston 20. The diameter of the orifice 30 is then adapted accordingly to hold the piston.

[0051] Several piston guides 3 and several pistons 20 having different rod diameters D200 can thus be mounted on the same pump body 10. Each of the different pistons 20 is associated with a piston guide whose orifice 30 corresponds to the rod diameter D200. Different pump heads 12 can also be used for the same pump body.

[0052] In order to prevent rotation of the piston 20 under the influence of the drive shaft 112, the pump according to the present description comprises a anti-rotation device 5 (figure 2, 3a, 3b). According to one embodiment, the piston 20 or a part of the piston 20 such as its base 201, is guided in translation by a fixed element combined or integrated with the pump body 10. The anti-rotation device 5 may for example comprise one or more grooves 51 oriented along the longitudinal axis X and arranged on the perimeter of the base 201 of the piston 20. The internal surface of the pump body 10 may comprise a lip 52 or a lug cooperating with such a groove 51 so as to prevent any rotational movement of the piston 20. In particular, the thickness of such a lip or lug corresponds to the width of the corresponding groove 51, with nevertheless just the clearance necessary to allow its longitudinal sliding.

[0053] A reverse configuration can nevertheless be envisaged, in which the internal surface of the pump body 10 comprises a groove 51 oriented parallel to the longitudinal axis X and the base 201 of the piston 20 comprises a lip 52 or a lug movable along this groove. According to a particular arrangement, one end of the groove 51 can be flared, in particular the end furthest from the rod 200, so as to facilitate the installation of the piston 20 by the second end 10b of the pump body 10. Alternatively or in addition, the second end 112b of the drive shaft 112 can be beveled so as to better fit into the piston housing 204. According to such an arrangement, the anti-rotation device 5 can serve as a guide means for the installation of a piston in the pump body 10.

[0054] In order to control the stroke of the piston 20, the pump comprises at least one detection system 6 for detecting the linear position of the piston 20. In this case, such a detection system 6 makes it possible to determine at least one end-of-stroke position, preferably the two opposite end-of-stroke positions of the piston. Such a detection system 6 can also make it possible to determine one or more intermediate positions of the piston. Alternatively or in addition, such a detection system 6 can determine the instantaneous position of the piston 20 on its path. Thus, the pitch of the motor can be adjusted if necessary.

[0055] Several systems can be envisaged for this purpose. Angular position sensors can for example be installed at the drive shaft 112 to determine its angular position and deduce the linear position of the piston 20.

[0056] According to a preferred embodiment, the linear position of the piston 20 is determined directly. The piston 20 may then comprise at least one fixed index 203 identifiable by one or more detectors such as a first 61 and / or a second 62 detectors fixed to the pump body 10, directly or via one or more intermediate parts. According to an example described in more detail below, such detectors may be fixed to an electronic card fixed to the pump body 10. The index and the associated detectors may be of any type, such as magnetic or optical. For example, an optical type index 203 may be arranged on the base 201 of the piston 200 so as to be detected by a first 61 and / or a second 62 optical detectors. The first 61 and second 62 detectors are arranged so as to detect respectively a first end of travel and a second end of travel of the piston 20.A first end of travel may correspond, for example, to a low position of the piston 20, and / or to a maximum withdrawal of the rod 200 from the chamber 121. A second end of travel position may correspond to a high position of the piston and / or to the maximum engagement of the rod 200 in the chamber 121. The movement from the low position, or the first end of travel, to the high position, or the second end of travel, produces the ejection of the liquid L through the outlet 122. The opposite movement from the high position to the low position produces a suction of the liquid L through the inlet 120.

[0057] According to an advantageous aspect, the detection system 6 is independent of the anti-rotation device 5. In other words, the anti-rotation device 5 does not make it possible to determine the linear position of the piston and the detection system has no influence on the rotation of the piston 20. Such an arrangement makes it possible to avoid possible detection errors due to the wear of mechanical parts included in the anti-rotation device 5. In addition, the position detectors, in particular the first 61 and second 62 optical detectors can be arranged and / or adjusted independently of the anti-rotation device 5.

[0058] According to an advantageous embodiment, the pump according to the present description comprises a lateral opening 101 allowing easy access to the interior of the pump body 10. The lateral opening 101 can be arranged at the height of the anti-rotation device 5. It can be for example diametrically opposite the anti-rotation device 5 or at an angular position of 90° or 120° of the anti-rotation device 5. Other angular values ​​can be envisaged as required, taking into account for example the accessibility aspects necessary for possible maintenance operations. Preferably, the longitudinal dimension of the lateral opening 101 is sufficient to remove the piston 20 from the pump body 10 if necessary, the longitudinal dimension of the lateral opening 101 can for example represent between half and two-thirds, or between two-thirds and three-quarters of the length of the pump body 10.The width of the side opening is also suitable for piston removal.

[0059] According to one embodiment, the lateral opening 101 is longer than the distance separating the first 61 and second 62 detectors.

[0060] The lateral opening 101 comprises a fixing surface 101a allowing it to be concealed by a protective cover or any equivalent. Preferably the fixing surface 101a is flat so as to affix a flat cover to it, but other arrangements can be envisaged.

[0061] According to an advantageous embodiment, the lateral opening 101 is concealed by a control card 7 comprising one or more connectors 71 and / or one or more electronic components 72 adapted to process and / or transmit information such as operating parameters of the pump or control instructions. The card 7 is preferably flat and arranged on the fixing surface 101a so as to make its connectors 71 and electronic components accessible from the outside. The operating parameters include the position linear of the piston 20, the angular position of the drive shaft 112, the temperature of the motor 110, the electrical consumption of the motor 110, the pressure of the liquid L, the dimensions of the piston 20 if applicable, the ambient humidity, the ambient temperature, the atmospheric pressure and any other parameter deemed useful. The control instructions include, for example, solenoid valve commands, the activation of the stepper motor 110, the direction of rotation of the drive shaft 112, the angular distance of a motor step, and any other useful command.

[0062] The card 7 may be provided, on its face facing the inside of the pump body 10, opposite that comprising the connectors 71 and the electronic components 72, with at least one detector making it possible to determine a position of the piston 20. Preferably, the first 61 and second 62 detectors are both arranged on the card 7. The card 7 is fixed on the fixing surface 101a so that the first 61 and second 62 detectors are correctly positioned in the pump body 10.

[0063] The position index 203, better detailed in Figure 4, is then arranged on the piston 20 opposite the first 61 and second 62 detectors. According to such an arrangement, the position index 203 is arranged on the piston 20 facing the lateral opening 101. According to a preferred arrangement, the position index 203 is arranged on the piston diametrically opposite the guide device 202. Preferably, the position index 203 is arranged at the periphery of the base of the piston 201, the distance of which from the first 61 and second 62 detectors is minimal.

[0064] According to one embodiment, the pump described here comprises a means for continuous lubrication of the drive shaft 112. According to the embodiment described in FIG. 5, the second end 112b of the drive shaft 112 forms, with the piston housing 204, a lubricant reservoir. Such a lubricant makes it easier to move the first drive nut 41 on the thread of the drive shaft 112 during its rotation and must therefore be able to spread over the thread automatically. When the second end 112b of the drive shaft 112 comes into contact with the bottom 204a of the piston housing, the lubricant contained in the reservoir spreads over the walls of the piston housing 204 and makes it possible to lubricate the thread during successive movements of the drive shaft 112 in the piston housing 204.

[0065] According to one embodiment, the second end 112b of the drive shaft 112 comes into contact with the bottom 204a of the piston housing 204 when the piston is in the low position, or at its first end-of-stroke position. According to such an arrangement, the bottom 204a of the piston housing 204 can serve as a stop for the stroke of the piston. Under these conditions, lubrication is carried out automatically at each translation cycle of the piston 20. Alternatively, the depth of the piston housing 204 is determined so that the second end 112b of the drive shaft 112 does not touch the bottom 204b when the piston reaches its first end-of-stroke, leaving a residual volume corresponding to the volume of lubricant in the reservoir.A further rotation of the drive shaft 112 is then necessary to move the piston 20 beyond its first end of travel so as to bring the second end 112b of the drive shaft 112 into contact with the bottom 204a of the housing 204. Under these conditions, a lubrication operation independent of the operating cycles of the piston 20 can be determined, which makes it possible to extend the lubrication duration with a given quantity of lubricant. The lubricant designates an oil or grease suitable for the device.

[0066] Figure 6 shows in detail an example of a drive shaft according to the present invention. According to this embodiment, the drive shaft 112 comprises a first threaded portion 1120 at its first end 112a, so as to cooperate with the shaft attachment 113, which may take the form of a thread. The shaft attachment may in this case be obtained by means of a nut or directly threaded into the base 11. At the opposite end 112b, the drive shaft may comprise a gripping means 8, making it possible to receive a screwing tool. The gripping means 8 may be in the form of a recess of suitable geometry, forming for example a polygon such as a hexagon or an octagon, a slot, a cross, a star or any equivalent, so as to be able to use a screwdriver or an Allen key or any equivalent. Alternatively, the gripping means 8 comprises one or more flats on the surface of the drive shaft 112, at its second end 112b. The end 112b of the drive shaft 112 can thus form a polygon such as a square, a hexagon or an octagon adapted to cooperate with a flat spanner or any equivalent. In this way, the drive shaft 112 can be screwed at the shaft attachment 113 from its second end 112b by means of a suitable tool. Preferably, the tightening tool is a standard tool. Alternatively, a specific geometry tool can be used, in particular to reserve the manipulations of the drive shaft to qualified persons possessing such a tool.

[0067] The diameter of the first threaded portion 1120, at the second end 112b, may be smaller than that of the drive shaft 112 at its second end 112b. A first shoulder 1121 may then be provided, delimiting an intermediate portion 1122. The intermediate portion passes through the motor 110. Its diameter is adapted to allow the rotation of the drive shaft 112 by the motor 110. The intermediate portion 1122 may comprise a guide zone 1123, in particular allowing the drive shaft to be precisely held along the axis of rotation X. For this purpose, the guide zone may cooperate with the centering device 115. The intermediate zone may be delimited by a second shoulder 1124. It is then located between the first 1121 and the second 1124 shoulders.The drive shaft 112 comprises a drive zone 1125 between the second shoulder 1124 and the second end 112b, adapted to cooperate with the transmission system 4, in particular with the first 41 and second 42 drive nuts. For this purpose, the drive zone comprises a suitable thread and diameter. Such a drive shaft 112 is easily removable and can be replaced by a different drive shaft. In this case, the diameter of the drive zone 1125 can be adapted according to the pumping or metering needs. In the event of replacement of the piston, the diameter of the drive zone 1125 is then brought into line with the dimensions of the piston housing 204.

[0068] According to one embodiment, the diameter of the drive zone 1125 is uniform between the second shoulder 1124 and the second end 112b. Alternatively, the second end 112b, intended to be inserted into the piston housing 204, may have its own diameter.

[0069] The pump described herein may further comprise or be connected to one or more sensors such as a temperature sensor such as an infrared sensor or a thermocouple or a thermometer, an ultrasonic sensor, a pressure sensor, an electrical voltage or electrical consumption sensor, a vibration sensor, an ambient temperature sensor, a humidity sensor or an atmospheric pressure sensor.

[0070] The data collected by one or more of these sensors can be transmitted by the control card 7, directly fixed on the pump 1. Alternatively, this data or part of it can be transmitted remotely, via an appropriate network such as an internet, intranet or radio network. Alternatively or in addition, this data or part of it can be transmitted via Wi-Fi or Bluetooth communication or any equivalent. The pump 1 is then provided with the appropriate means of communication.

[0071] The pump described here may comprise or be connected to a data processing module (not shown) so as to process the collected data according to relevant algorithms. The algorithms used are suitable for determining the operating state of the pump, for example, its instantaneous or average electrical consumption, its state of wear, its vibration level, its noise level, its lubrication state or any other operating parameter. The collected data may further be used for the purpose of predicting maintenance operations or replacement of certain parts, or the end of life of the pump 1 or breakdowns. Alternatively or in addition, the collected data may be analyzed so as to adapt the operating parameters of the pump according to those of the environment such as hygrometry, ambient temperature, atmospheric pressure or any other relevant parameter.

[0072] The pump described herein or the data processing module may include or be combined with one or more artificial intelligence programs adapted to the analysis of the data collected for the purposes mentioned herein.

[0073] The design of the pump according to the present description allows easy maintenance operations, in particular thanks to the lateral opening 101 and the piston passage 100 significantly wider than the diameter of the rod 200. In addition, the piston 20 can easily be replaced by a different piston as required. It can for example be removed by pulling along the longitudinal axis X to detach it from the first drive nut 41. Alternatively, it can be removed with the first drive nut 41 by completely unscrewing it from the drive shaft 112. The removal of the piston 20 advantageously allows access to the second end 112b of the drive shaft 112 and, if necessary, to refill the piston housing 204 with lubricant. Alternatively, the piston can be removed from the pump body 10 through its lateral opening 101 after dismantling the card 7.

[0074] According to one embodiment, the position of the position index 203 on the piston can be modified. For example, the base 201 of the piston 20 can have several predetermined locations for arranging a position index 203 there. Alternatively or in addition, one or more of the position detectors can be modified as required. For example, the card 7 comprising the first 61 and second 62 detectors can be replaced by another card 7 in which the position of the first 61 and second 62 detectors or one of them is different. The stroke of the piston 20 can then be easily modified.

[0075] This description also covers a kit, comprising a pump 1 as described herein and one or more additional pistons 20. The or the additional pistons preferably have the same piston base 201. In particular, the piston housing 204, the position index 203 and the guide device 202 are identical for all the pistons. The pistons are differentiated by their rod 200. They may have different rod diameters D200 so as to be able to adapt the flow rates of the pump 1 according to the needs. In the case where the position of the first 61 and second 62 detectors can be adjusted, the length of the rod 200 of the piston may vary from one piston to another. The kit comprises one or more additional piston guides 3 adapted to the different pistons. In this case, the different piston guides 3 may have a bearing surface 31, assembly points 33 and a setting 32 that are identical, and a central orifice 30 of different diameter. The kit may include one or more complementary pump heads 12 whose chamber diameter 121 is adapted to that of the corresponding piston rod.

[0076] According to one embodiment, a given card 7, comprising at least one detector, can be used for several of the pistons or all of them. According to another embodiment, several cards 7 can be associated with the pistons used, for example to adapt the position detector(s) and / or the control parameters.

[0077] The present description further covers a method for pumping, dispensing, sampling or metering a liquid L by means of the pump 1 described herein. The method comprises for this purpose a step of connecting the liquid inlet 120 and outlet 122 to appropriate conduits. It further comprises the step of activating the motor so as to alternately rotate the drive shaft 112 by a given angular value in one direction of rotation then in the opposite direction, so that the piston 20 moves in translation between a first end-of-travel position and a second end-of-travel position along the longitudinal axis X. The translation cycles of the piston in the chamber 121 allow in turn to suck the liquid through the inlet 120 and to discharge it through the outlet 122.

[0078] The angular amplitude and / or frequency of the drive shaft 112 can be controlled manually or automatically according to a pre-established program or parameters determined in real time. Automated control may involve artificial intelligence. Thus, the motor pitch can be adjusted in real time or predetermined by a given program.

[0079] The present method includes an automatic lubrication step for the drive shaft 112. Lubrication can be inherent to the translational movement of the drive shaft within the piston housing. Alternatively, a specific lubrication operation can be initiated by bringing the drive shaft into contact with the bottom of the piston housing.

[0080] The method described herein may further include a step of considering one or more environmental parameters, such as ambient temperature, humidity, and atmospheric pressure, and determining a suitable amplitude and / or rotational frequency of the drive shaft 112. These environmental parameters also allow for improved accuracy in pumping or dosing the liquid.

[0081] The method according to this description may alternatively or in addition include a step of considering one or more operating parameters of the pump such as the electrical consumption of the motor, vibrations, the emission of one or more sound ranges of the pump, the temperature of the motor, and of determining an appropriate amplitude and / or frequency of rotation accordingly and / or of issuing an alarm signal if necessary, and / or of transmitting an instruction for revision or maintenance of the pump if necessary.

[0082] One or more maintenance steps can be automated. For example, a lubrication step can be initiated automatically based on the collected parameters. In this case, a adequate movement of the drive shaft 112 until contact with the bottom of the piston housing 204 can be initiated to lubricate the threads of the drive shaft.

[0083] The method according to the present description may alternatively or additionally comprise a step of considering one or more operating parameters of the pump such as the electrical consumption of the motor, the vibrations of the motor, the emission of one or more sound ranges of the pump, the temperature of the motor, and / or one or more environmental parameters such as the ambient temperature, the hygrometry, the atmospheric pressure, and of processing them by means of appropriate algorithms so as to produce an operating status and / or an operating prognosis comprising one or more elements from among a prediction of wear of one or more parts, an anticipation of replacement of one or more parts, an upcoming maintenance deadline, a prediction of failure, a prediction of end of life of the pump.

[0084] The pump described herein allows the distribution and / or metering of liquids, in particular for medical, diagnostic or therapeutic purposes, for research purposes, for analytical purposes. The liquids mentioned herein include all types of liquids, in particular liquids of varying viscosity at varying pressures. The liquids include solutions of active ingredients, test or diagnostic solutions, injection solutions, infusion solutions, physiological fluids such as blood. Reference numbers used in the figures 1 Piston pump 10 Pump body 10a, 10b Pump body ends 100 Piston passage 101 Side opening 101a Fixing surface 102 Anti-rotation device 11 Base 110 Engine 111 Connection 112 Drive shaft 112a First end of drive shaft 112b Second drive shaft end 1120 Threaded portion 1121 First shoulder 1122 Intermediate portion 1123 Guidance Zone 1124 Second shoulder 1125 Training area 113 Tree fixing 114 Thread 115 Centering device 12 Head 120 Liquid inlet 121 Room 122 Liquid outlet 20 Piston 200 Piston rod 200a Rod end 201 Piston Base 202 Guidance device 203 Position Index 204 Piston housing 204a Piston housing bottom 3 Piston guide 30 Orifice 31 Support surface 32 Piston guide timing 33 Assemblage Point 4 Transmission system 41 First training nut 410 Col 42 Second training nut 43 Spring L Liquid 5 Anti-rotation device 51 Groove 52 Lip 6 Detection system 61 First detector 62 Second detector Control board Connectors Electronic components Clamping means

Claims

Claims 1. Piston pump (1) comprising: - a pump body (10) having a first (10a) and a second (10b) end oriented along a longitudinal axis (X), comprising a piston (20) adapted to move in translation along the longitudinal axis (X), which comprises a piston rod (200) having a rod diameter (D200) and a piston base (201), the piston base being provided with a piston housing (204), - a pump base (11) fixed to a first end (10a) of the pump body, comprising a motor (110) adapted to actuate in rotation along the longitudinal axis (X) a drive shaft (112) comprising a thread (114), - a transmission system (4) connecting said drive shaft (112) to said piston (20), so that a rotational movement of the drive shaft (112) produces a translational movement of the piston (20), - an anti-rotation device (5) adapted to block the rotation of the piston (20) during the rotation of said drive shaft (112), - a pump head (12) comprising an inlet (120) for liquid (L), an internal chamber (121), in communication with the rod (200) of the piston (20) and a liquid outlet (122), the pump head (12) being associated with the second end (10b) of the pump body (10), and - a piston guide (3) arranged at the second end (10b) of the pump body (10), comprising an orifice (30) with a diameter corresponding to the rod diameter (D200) of the piston rod (200) and a wedging device (32) adapted to center the piston guide (3) on the pump body (10), said pump head comprising a fixing device cooperating with the pump body (10), said piston guide (3) comprising one or more assembly points (33) compatible with the pump head fixing device (12), so as to be able to be fixed on the pump body (10) by means of the pump head fixing device.

2. Pump according to claim 1, the pump body (10) comprising a lateral opening (101) and a control card (7) obscuring said lateral opening, said control card comprising on its internal surface at least one position detector, such as a first (61) and / or a second (62) detector, said piston comprising a position index (203) identifiable by said at least one position detector.

3. Pump according to claim 2, said control card (7) comprising on its external surface one or more connectors (71) and / or electronic components (72).

4. Pump according to one of claims 1 to 3, the anti-rotation device (5) of the piston (20) comprising a groove (51) arranged on the circumference of the piston base (201) and oriented along the longitudinal axis (X) and a lip (52) or a lug arranged on the internal surface of the pump body (10) so as to cooperate with said groove to block the rotation of the piston while allowing its translation.

5. Pump according to one of claims 1 to 4, said transmission system (4) comprising a first drive nut (41) threaded in its center and in contact with the piston base (201), said first drive nut being arranged on the thread of the drive shaft (112) so as to move the piston in translation during rotation of the drive shaft (112).

6. Pump according to claim 5, said transmission system (4) comprising a second drive nut (42) threaded in its center and arranged on the thread of the drive shaft (112) and a spring (43) arranged between the first (41) and the second (42) drive nuts.

7. Pump according to one of claims 1 to 6, said drive shaft (112) comprising a first threaded portion (1120) arranged at its first end (112a) so as to cooperate with a shaft attachment (113) on the base (11) of the pump, an intermediate portion (1122) adapted to cooperate with the motor (110), a drive zone (1125) cooperating with the transmission system (4), and a second end (112b) housed in the piston housing (204), said second end (112b) of the drive shaft (112) forming with the piston housing (204) a reservoir suitable for receiving lubricant.

8. Pump according to one of claims 1 to 7, comprising or being connected to one or more sensors among a temperature sensor, an ultrasonic sensor, a vibration sensor, a pressure sensor, an ambient temperature sensor, an atmospheric pressure sensor, a hygrometry sensor, an electrical consumption sensor and / or comprising or being connected to a module for processing the data collected by said one or more sensors and / or one or more artificial intelligence programs adapted to the analysis of the collected data.

9. Kit comprising a pump according to one of claims 1 to 8, one or more additional pistons having rods (200) of different diameters (D200), and one or more additional piston guides all having the same assembly points (33) and orifices of different diameters, each corresponding to the rod diameters (D200) of said additional pistons.

10. Method for pumping, metering or dispensing a liquid (L) by means of a pump according to one of claims 1 to 9, comprising activating the motor to alternately rotate the drive shaft (112) by a given angular value in one direction of rotation then in the opposite direction so as to move the piston (20) in translation along the longitudinal axis (X) between a first and a second end-of-stroke position and one or more of the steps of: - replace the piston (20) with another piston whose rod (200) has a different diameter (D200) while retaining the pump body (10); - consider one or more environmental parameters and / or one or more operating parameters of the pump and adapt said motor pitch and / or predict an event among a breakdown, a maintenance operation or the end of life of the pump; and - automatic lubrication of the drive shaft (112).

Images