Rotor assembly for laboratory centrifuge.

Abstract

The present invention relates to a rotor (1) closed by a cover (2), intended to equip laboratory devices of the centrifuge type, mainly with a vertical rotation axis, characterized in that the cover (2) comprises a single part (11) (hood) intended to close the chamber (3) arranged in the rotor (1) where the samples to be centrifuged are placed, free to rotate relative to the operating means (10) and locking means (14) of said cover (2) and that the sealing joints (12, 13) are only in contact with the rotor (2) and this single part (11).Since this cover (11) is free to rotate on the operating means (10) of the cover (2), the rotation by the user of said operating means (10) of said cover (2) to lock or unlock said cover (2) on said rotor (1) does not cause any relative movement between said cover (11) and said rotor (1), and as a positive consequence, no frictional force between the seals (12 and 13) and the rotor (1) or the cover (11). Figure for abstract: Figure 3.

Description

Title of the invention: Rotor assembly for a laboratory centrifuge. TECHNICAL FIELD TO WHICH THE INVENTION RELATES

[0001] The present invention relates to a rotor assembly equipped with a cover, intended to equip laboratory devices of the centrifuge type, mainly with a vertical rotation axis. TECHNOLOGICAL BACKGROUND

[0002] Centrifugation allows the separation of constituents of very variable size and mass contained in a liquid sample, from molecules to whole cells. These samples can be contaminated and / or contaminating and must be kept in their containers.

[0003] These centrifugation techniques are conventionally implemented using laboratory centrifuges which comprise a chamber containing two rotating parts, namely: - A drive motor shaft, associated with motor means for its rotational maneuver, and; - A rotor, intended to be mounted on said motor shaft and intended to receive the containers in which the liquid samples to be centrifuged are returned. Some rotors are said to be "open" when the chamber intended to receive the containers is left open to the air. Others are "closed" by a cover, in particular when the user wants to limit the risk of propagation of contaminated agents and / or contaminants which may constitute the sample to be centrifuged, in the event of breakage of a container.

[0004] In a conventional manner, these two rotating parts are provided with complementary assembly means for the removable mounting of the rotor on the free end of the drive motor shaft. These assembly means comprise: - A centering and rotation locking means, such as for example a conical connection, splines, a key or other rotation stop means. Traditionally, these rotation locking means consist of a male part carried by the drive motor shaft and a female part carried by the rotor body, and; - A translational locking means such as a nut, or a system that can be manipulated without tools, such as that described in patent EP2799148.

[0005] When the user wishes to guarantee maximum safety and avoid any risk of propagation of the potentially pathogenic sample in the atmosphere, he uses rotors equipped with sealed covers traditionally screwed onto the rotor either by male / female threads made on the cover on the one hand and the rotor on the other hand, or by the use of a screw, often central (WO9407606 or US4850951). But this screwing solution, although it has the advantage of appearing simple, has the major disadvantage of only guaranteeing the sealing of said cover on said rotor on the condition of screwing the cover "fully" to compress the seals involved in obtaining the desired seal, generating significant forces when screwing and risks of blockage when unscrewing due to the compression and friction of said seals.

[0006] Patent EP4180131 attempts to propose a solution to the difficulties presented above, by replacing the thread between the cover and the rotor with a groove made in the rotor and in which a protrusion made in the cover slides. The expected advantage is to use the gravitational force so that the cover descends as close as possible to the final position, then to complete the tightening, and the compression of the seals ensuring the expected seal between the rotor and its cover, by the relative movements of the parts during the centrifugation phase (the cover lags behind the rotor which is directly driven by the motor shaft and in fact, amplifies the tightening of said cover). In this case, if the forces at closing are indeed eliminated, those at opening are still present.

[0007] US patent 10493469 proposes a solution with hooks as axial locking means, not requiring rotation of the cover during closing and opening operations and therefore a priori, without forces induced by sliding of the seals. But the hook mechanism is quite complex to produce. SUBJECT OF THE INVENTION

[0008] In order to remedy the defects previously exposed, we propose a sealed rotor (1) and cover (2) assembly, with ergonomics which guarantee both: - Optimal seal compression guaranteeing the expected seal between the rotor on the one hand and its cover on the other; - Effortless locking; - A mechanism ensuring that the cover is kept in the effective closed position, also acting as an indicator to avoid any misinterpretation on the part of the user as to the actual closed state of said cover on said rotor, and; - Effortless and secure opening as it requires two simultaneous movements. To achieve this, we propose a cover fixed to the rotor by exclusively axial means and whose seals are freed from the constraints linked to the movements necessary for fixing or opening the cover.

[0009] The rotor assembly comprises: - A rotor (1), intended to receive containers (themselves containing samples intended to be centrifuged), and; - A cover (2), intended to tightly close the chamber made in the rotor.

[0010] The rotor (1) comprises: - A chamber (3) in which at least one location (4) is arranged which is suitable for receiving a container containing a sample to be centrifuged; - An access opening, opening into said chamber (3) for access to said at least one location (4); - A locking means (5) capable of cooperating with the motor shaft. In the preferred embodiment, we use the solution proposed in patent EP2799148 without this choice being limiting, a simple nut could also work; - An axial locking means (6) capable of cooperating with the cover (2); - A safety means (7) maintaining the cover in the effective locking position - A surface (8) on which a peripheral seal (12) will make a first sealing barrier closing said chamber (3) when the cover (2) is locked on said rotor (1). In the preferred embodiment, this peripheral seal (12) is axially compressed, and said compression surface (8) is flat, and; - A surface (9) on which a central seal (13) will make a 2nd sealing barrier closing said chamber (3) when the cover (2) is locked on said rotor (1). In the preferred embodiment, this central seal (13) is radially compressed, and said compression surface (9) is a bore.

[0011] The cover (2) comprises: - A means of maneuver (10); - A cover (11) formed from a single piece, intended to close the chamber (3) arranged in said rotor (1), fixed in translation and free in rotation relative to the operating means (10) and locking means (14) of said cover (2), carrying if necessary one or more seals (12, 13) in order to obtain the expected seal between said rotor (1) and said cover (11), and therefore said cover (2); - At least one seal (12, 13) intended to seal the chamber (3) arranged in the rotor (1) when the cover (2) is locked on said rotor (1) and carried by the hood (11); - A locking means (14) fixed to the operating means (10), capable of cooperating with the rotor (1), and; - A safety means (10a) holding the cover (2) in the effective locking position.

[0012] According to the invention, the seal(s) (12, 13) intended to seal the chamber (3) arranged in the rotor (1) is (are) in contact exclusively with said rotor (1) on the one hand and with said cover (11), part of the cover (2) on the other hand. The combination of this exclusivity, and the freedom of rotation of said cover (11) relative to the operating means (10) of said cover (2) makes it possible to isolate the seal(s) (12, 13) from the rotation of the operating means (10) of said cover (2) by the user when closing or opening said cover (2) on said rotor (1), and therefore not to create force due to sliding of the seal(s) on its contact surfaces unlike the examples given in the technological background. This is how the invention meets the stated objectives of effortless closing and opening.

[0013] According to the invention, the axial locking of the cover (2) on the rotor (1) is obtained by the cooperation of two locking means (6, 14) having complementary shapes which, depending on the relative angular position of these said locking means (6, 14), allow or prevent axial movement of the cover (2) relative to the rotor (1). In the preferred embodiment: - The rotor (1) is equipped with a locking means (6) taking the form of a disc having 4 ears (6a) projecting on its periphery; - The cover (2) is equipped with a locking means (14) taking the form of a ring having 4 internal clearances (14a); It will be understood that when the ears (6a) of the locking means (6) equipping the rotor (1) and the clearances (14a) of the locking means (14) equipping the cover (2) are in a relative angular position where they are face to face, they allow free axial movement of said cover (2) relative to the rotor (1), allowing the ring (14) to be placed at will above or below the disc (6), i.e. the cover (2) outside the rotor (1) or in the latter. It will also be understood that when the ears (6a) of the locking means (6) equipping the rotor (1) and the clearances (14a) of the locking means (14) equipping the cover (2) are in a relative angular position where they are no longer face to face, they do not allow free axial movement of said cover (2) relative to the rotor (1), axially locking the cover (2) on the rotor (1) if the ring (14) is under the disc (6).

[0014] Still according to the invention, the rotor (1) is equipped with at least one safety means (7) which cooperates with a complementary safety means (10a) on the operating means (10) of the cover (2) after the cover has been axially locked on the rotor (1) using the axial locking means (6 and 14) provided for this purpose. This safety means (7) has the objective of locking the cover (2) on the rotor (1) in an angular position where the axial locking means (6 and 14) do not allow axial movement of the cover (2) relative to the rotor (1). In a preferred embodiment, this safety means (7) takes the form of a pin (7a) held in position by a spring (7b) which is placed in a complementary means (10a) taking the form of a hole, made in the operating means (10) of the cover (2), only if said cover (2) is already axially locked. It will then be understood that when, and only when, said safety means (7) cooperates with the complementary safety means (10a) of the operating means (10) of the cover (2), said safety means (7) is visible through said complementary safety means, then acting as an indicator of the effective closure of said cover (2) on the rotor (1).

[0015] The invention will be clearly understood upon reading the following descriptions of particular embodiments including the locking means (5) with the motor shaft according to patent EP2799148, without these examples being in any way limiting, with reference to the appended drawings in which:

[0016] [Fig-1] Is a general view, in section and with a slight perspective, of the rotor (1) according to the invention. We see: - The chamber (3) arranged in said rotor (1) and some locations (4) intended to receive the samples to be centrifuged. In this figure the locations are left empty for better readability of the drawing; - In the center of the rotor (1), the locking means (5) with the motor shaft according to patent EP2799148. We will not dwell here on explaining its operation since it is not at the heart of the invention and could be replaced by any other locking means including a simple nut. - In the center of the rotor (1), under the locking means (5), a disc (6) having 4 ears (6a) projecting on its periphery and acting as a means of axial locking of the cover (2) on the said rotor (1), the said disc (6) being able to cooperate with the ring (14) of the said cover (2) as shown in the following figure, and - On the periphery of the rotor (2), at least one safety means (7) capable of cooperating with the at least one complementary safety means (10a) produced on the operating means (10) of the cover (2), visible in the following figures. In the preferred embodiment, this safety means (7) takes the form of a pin (7a) mounted on a spring (7b) which retracts into its housing (15) as long as the complementary safety means (10a) produced on said operating means (10) of said cover (2) is not placed directly opposite it, and which cooperates with said complementary safety means (10a) produced on said operating means (10) of said cover (2) as soon as they are placed directly opposite each other, as we will see in the following figures. Still in the preferred embodiment, we prefer to place as many safety means (7) as there are ears (6a) projecting on the periphery of the locking means (6) of the cover on the rotor (1) in order to obtain as many locked positions of said cover as there are inputs.

[0017] [Fig.2] Is a general perspective view of the cover (2) favoring a vision from above it, that is to say close to what the user sees when handling the said cover. We see: - An operating means (10) comprising a gripping element (10b) here in the form of a crown which allows the user to hold said cover (2) and to impart a rotational movement thereto in the clockwise direction to close said cover (2) and in the anticlockwise direction to open it. - An opening (10c) arranged in the center of said operating means, passing through it from one side to the other, and which allows, once the cover (2) is placed on the rotor (1), access to the locking means (5) fixed to said rotor (1), and - At least one complementary safety means (10a) intended to cooperate with the at least one safety means (7) placed on the rotor (1) when said cover (2) is locked to said rotor (1). In the preferred embodiment, this additional safety means (10a) takes the form of a hole in which one of the pins (7a) forming one of the safety means (7) attached to the rotor (1) is placed as soon as these said safety means (7 and 10a) are placed coaxially. Still in the preferred embodiment, this additional safety means (10a) is 1 in number to limit aerodynamic disturbances during rotation of the rotor in the centrifuge.

[0018] [Fig.3] Is a general view in section and in perspective of the cover (2) favoring a view from below it, that is to say on its functional elements, hidden from the user when said cover (2) is locked on said rotor (1). We see: - On the periphery, the maneuvering means (10) essentially visible in the previous figure; - Towards the center, a cover (11) fixed axially on the operating means (10) and free to rotate thereon, intended to close the chamber (3) arranged in the rotor (1) and carrying, if necessary, one or more seals (12, 13) in order to obtain the expected seal between the said rotor (1) and the said cover (2). - A peripheral seal (12) carried by said cover (11) and intended to seal the chamber (3) arranged on said rotor (2). In the preferred embodiment, this peripheral seal is axially compressed. - A central seal (13) carried by said cover (11) and intended to seal the chamber (3) arranged on said rotor (1). In the preferred embodiment, this peripheral seal is compressed radially. - In the center, an axial locking means (14) of the cover (2) on the rotor (1). In the preferred embodiment, this locking means (14) is a ring having internal clearances (14a). This locking means (14) is integral with the operating means (10) of said cover (2). and also allows the cover (11) to be fixed axially and leaves it free to rotate.

[0019] [Fig.4] Is a general view, in section and with a slight perspective of the rotor assembly (1), when the cover (2) is approaching, not locked. We see: - The safety means (7) held in the “high” position by the springs (7b) placed for this purpose under the pins (7a) which constitute these safety means (7). - The cover (2) above these safety means (7) because placed at an angle which does not allow the coaxiality of these means (7) with the at least one complementary safety means (10a) produced on the operating means (10) of the cover (2). - The axial locking means (14) of the cover (2) and that (6) placed on the rotor (1). These two means (6 and 14) with complementary shapes (ears (6a) and clearances (14a)) are placed in an angular position allowing axial movement between the two parts.

[0020] [Fig.5] Is a general view, in section and with a slight perspective of the rotor assembly (1), when the cover (2) is pushed into the rotor, after an axial displacement of the cover (2), not locked. We see: - The safety means (7) are kept in the “low” position, the springs (7b) placed under the pins (7) being compressed. - The cover (2) pressing on these safety means (7) because placed at an angle which does not allow the coaxiality of these means (7) with the at least one complementary safety means (10a) produced on the operating means (10) of the cover (2). - The axial locking means (14) of the cover (2) and that (6) on the rotor (1) These two means (6 and 14) with complementary shapes (ears and clearances) are placed in an angular position allowing axial movement between the two parts. It will be understood from reading this figure that at this stage, if the user releases the cover (2) it will be pushed out of the rotor by at least one safety means (7) placed on the rotor thanks to the force exerted by the spring (7b) which constitutes at least one safety means (7).

[0021] [Fig.6] Is a general view, in section and with a slight perspective of the rotor assembly (1), when the cover (2) is pushed into the rotor, and locked after a clockwise rotation of the operating means (10) of the cover (2). We see: - A safety means (7) of the rotor cooperates with the complementary safety means (10a) produced on the operating means (10) of the cover (2) because they are placed coaxially with respect to each other; - The other safety means (7) of the rotor remain in the "low" position because in the preferred embodiment there are 4 of them compared to only 1 additional safety means (10a) on the operating means (10) of the cover (2). We could have chosen an equal number of safety means (7) on the rotor (1) and additional safety means (10a) on the operating means (10) on the cover (2) without modifying or reducing the scope of the invention. - The axial locking means (14) of the cover (2) and that (6) on the rotor (1). These two means (6 and 14) with complementary shapes (ears and clearances) are placed in an angular position not allowing axial movement between the two parts.

[0022] [Fig.7] are perspective views where only: - The ring (14) forming the axial locking means fixed to the operating means (10) of the cover (2) and; - The disc (6) forming the axial locking means fixed to the rotor (1) On the left, while these locking means (6 and 14) are in an angular position where their complementary shapes allow axial movement between the two parts. When closing the cover (2) on the rotor (1), this movement is from top to bottom; On the right, while these locking means (6 and 14) are in an angular position where their complementary shapes do not allow axial movement between the two parts. When closing the cover (2) on the rotor (1), this position is obtained after rotation of the operating means (10) of said cover (2) by the user.

[0023] It will be understood from reading these figures that to close the cover on the rotor, the user must: - Place the cover (2) on the rotor (1). The cover (2) is held out of its locking position because the complementary shapes made in the axial locking means (6 and 14) of the rotor (1) and the cover (2) are not in a relative angular position allowing axial movement of the two parts relative to each other, while the axial locking means (14) equipping the cover (2) is above the axial locking means (6) of the rotor (1). We are in the framework of [Fig.4]; - Move the cover (2) downwards, applying axial pressure; - Turn the operating means (10) of the cover (2) clockwise until the complementary shapes made in the axial locking means (6 and 14) of the rotor (1) and the cover (2) are in an angular position allowing axial movement of the two parts relative to each other; At this stage, the cover (2) is completely pushed into the rotor (1) but is not yet locked. We are in the frame of [Fig.5]; - Continue to turn the operating means (10) of the cover (2) clockwise until at least one safety means (7) of the rotor (1) cooperates with the complementary safety means (10a) of the operating means (10) of the cover (2) because they have become coaxial. In the preferred embodiment, the safety means (7) is composed of a pin (7) which, under the action of a spring (7b), is housed in a hole, forming the additional safety means (10a), made on the operating means (10) of the cover (2), which blocks said cover in the locked position. It may be noted that at this stage, the seals (12, 13) are in contact with the rotor (1) and the cover (11) of the lid (2). The friction between these parts, due to their respective materials, is sufficiently significant to stop the rotation of said seals (12, 13) and the cover (11) of the lid (2) relative to the rotor (1), without slowing down the manipulation of the operating means (10) of the lid (2), since said cover (11) is free to rotate on the operating means (10) of the lid (2). At this point the cover is locked onto the rotor. We are in the frame of [Fig.6]. As explained above, the pin (7a) constituting the safety means (7) of the rotor (1) passes through the hole (complementary safety means (10a)) passing through the operating means (10) of the cover (2), and therefore visible to the user, only when said cover (2) is actually locked on the rotor (1). We can therefore advantageously use this safety means (7) as an indicator because it is visible to the user when and only when the cover (2) is actually locked on the rotor (1).

[0024] It will be understood from reading these figures that to open the cover (2) on the rotor (1), the user must: - Release the cover (2) from the safety means (7) of the rotor (1) which cooperates with the complementary safety means (10a) of the operating means (10) of the cover (2) by voluntarily retracting the safety means (7) (keeping the pin (7a) which constitutes said safety means (7) pressed into its housing) of said rotor (1); - While holding this pin (7a) pressed, turn the operating means (10) of the cover (2) counterclockwise As soon as the operating means (10) of the cover (2) is in an angular position no longer allowing the safety means (7) of the rotor (1) to cooperate with the complementary safety means (10a) of the operating means (10) of the cover (2), said operating means (10) of said cover (2) keeps said at least one pin (7a) of said safety means (7) of said rotor (1) pressed into its housing (15). The spring (7b) which constitutes the safety means (7) of the rotor (1), placed under the pin (7) tends to push the cover (2) out of the rotor (1). - Continue to turn the operating means (10) of the cover (2) until the complementary shapes of the axial locking means (6 and 14) of the rotor (1) and the cover (2) are in a relative angular position allowing axial movement of the two parts relative to each other. At this moment, the cover lifts naturally thanks to the action of the spring (7b) which constitutes the at least one safety means (7) of the rotor (1), the pin (7) of which was until then held down by the cover (2). The cover (2) is released and the rotor (1) opens. During these rotations, the seals (12 and 13) are compressed between the rotor (1) and the cover (11) of the lid (2). Since this cover (11) is free to rotate on the operating means (10) of the lid (2), the rotation by the user of said operating means (10) of said lid (2) to lock said lid (2) on said rotor (1) does not cause any relative movement between said cover (11) and said rotor (1), and as a positive consequence, no friction force between the seals (12 and 13) and the rotor (1) or the cover (11).

Claims

Claims

1. Rotor (1) used in a laboratory centrifuge, characterized in that it comprises an axial locking means (6) capable of cooperating with a complementary means (14) fixed to a cover (2).

2. Rotor cover (2) according to claim 1, characterized in that it comprises: - A hood (11) formed from a single piece, intended to close a chamber (3) arranged in said rotor (1), - An operating means (10), - An axial locking means (14) capable of cooperating with the complementary means (6) secured to the rotor (1), said operating means (10) and axial locking means (14) being secured to each other, and said hood (11) being fixed in translation and free to rotate relative to the operating means (10) and axial locking means (14).

3. Rotor assembly (1) according to claim 1 and Cover (2) according to claim (2), characterized because their axial locking is obtained by the cooperation of two locking means (6, 14) having complementary shapes, such as ears (6a) and clearances (14a), which depending on the relative angular position of these said locking means (6, 14), allow or prevent axial movement of the cover (2) relative to the rotor (1).

4. Assembly according to claim 3, characterized in that the Rotor (1) and the Cover (2) are equipped with safety means such as a pin (7a) held in position by a spring (7b) which is placed in a complementary means (10a) taking the form of a hole, only when the said Cover (2) is fixed axially on the said rotor (1) and in an angular position where the axial locking means (6 and 14) do not allow axial movement of the cover (2) relative to the rotor (1).

5. Assembly according to claims 3 and 4, characterized in that at least one seal (12, 13) is in contact exclusively with said Rotor (1) on the one hand and with said Cover (11), forming part of the cover (2) on the other hand.

6. Laboratory centrifuge characterized in that it is equipped with an assembly according to claims 3 to 5.

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