Test tube carrier

A test tube carrier for transporting test tubes in a laboratory automation system is presented. The test tube carrier comprises a base body and at least three centering fingers attached to the base body. The centering fingers are distributed about a central axis (A). Each centering finger comprises an elongate, bent resilient element and a strut having a higher stiffness than the resilient element. The struts extend in parallel to the central axis (A). A first end of the associated resilient element is fixedly attached to the strut at an upper position and a second end of the resilient element contacts the strut at a lower position between the base body and the upper position. A laboratory distribution system having a number of test tube carriers, and a laboratory automation system comprising a laboratory distribution system are also presented.

BACKGROUND

The present disclosure relates to a test tube carrier for transporting test tubes in a laboratory automation system as well as to a laboratory distribution system having a number of test tube carriers and a laboratory automation system comprising a laboratory distribution system.

A laboratory automation system typically comprises a number of pre-analytical, analytical and/or post-analytical stations, in which samples, for example blood, saliva, swab and other specimens taken from the human body, are processed. It is generally known to provide test tubes containing the samples. The test tubes are also referred to as sample tubes.

Several test tubes can be placed in racks for a handling. In an alternative distribution system, test tubes are place in an upright or vertical position in so called test tube carriers or pucks having a retaining area for retaining test tubes.

Generally, in laboratory automation systems, different kinds of test tubes, in particular test tubes of different diameter are handled. It is further known to control the transport of the test tubes and/or a treatment of the sample contained in the test tube by a bar code provided on an outside surface of the test tube. For this purpose, the bar code should be readable during the transport and/or at all handling stations without needing to remove the test tube from the carrier.

Therefore, there is a need for a test tube carrier allowing for a secure support of different types of test tubes without hindering the readability of the bar code, or any other type of identification code, provided on an outside of the tube.

SUMMARY

According to the present disclosure, a test tube carrier for transporting test tubes in a laboratory automation system is presented. The test tube carrier can comprise a base body and at least three centering fingers attached to the base body. The centering fingers can be distributed about a central axis (A). Each centering finger can comprise an elongate, bent resilient element and a strut having a higher stiffness than the resilient element. The strut can extend in parallel to the central axis (A). A first end of the associated resilient element can be fixedly attached to the strut at an upper position. A second end of the resilient element can contact the strut at a lower position between the base body and the upper position when a test tube is inserted between the centering fingers and in the absence of a test tube. A contact portion of the resilient element between the first end and the second end can protrude towards the central axis (A).

Accordingly, it is a feature of the embodiments of the present disclosure to provide a test tube carrier allowing for a secure support of different types of test tubes without hindering a readability of the bar code or any other type of identification code provided on an outside of the tube. It is a further feature of the embodiments of the present disclosure to provide a laboratory distribution system and a laboratory automation system comprising a distribution system having a number of test tube carriers. Other features of the embodiments of the present disclosure will be apparent in light of the description of the disclosure embodied herein.

DETAILED DESCRIPTION

A test tube carrier for transporting test tubes in a laboratory automation system is presented. The test tube carrier can comprise a base body and at least three centering fingers attached to the base body. The centering fingers can be distributed about a central axis. Each centering finger can comprise an elongate, bent resilient element and a strut having a higher stiffness than the resilient element. The struts can extend substantially in parallel to the central axis. A first end of the associated resilient element can be fixedly attached to the strut at an upper position and a second end of the resilient element can contact the strut at a lower position between the base body and the upper position when a test tube is inserted between the centering fingers and in the absence of a test tube. A contact portion of the resilient element between the first end and the second end can protrude towards the central axis.

The base body can be part of a distribution system allowing the test tube carrier to be moved between different stations, for example by a conveyer belt, an assigned drive motor and/or a system, as described in WO 2013/064656 A1 and incorporated by reference, using a magnetically active device assigned to the carrier.

The resilient elements can be attached with a first end of the struts at an upper position. In one embodiment, the upper position can coincide to the upper end of the struts. In other embodiments, the struts can extend beyond the upper position. The second end of the resilient element can contact the associated strut at a position that can be lower than the upper position. The second end can contact the associated strut in the case the test tube carrier is empty as well as after receiving a test tube between the centering fingers.

When receiving a test tube between the centering fingers, the resilient elements can be deformed and the test tubes can be aligned with the central axis and clamped by the restoring forces. In use, different types of test tubes, in particular, test tubes of different diameters, can be transported by the test tube carrier. The resilient elements can allow for a compensation of different sizes. The struts having a higher stiffness than the resilient elements may not be deformed when receiving a test tube and prevent a permanent deformation of the centering fingers radially outwards. The resilient elements can be supported at the stiff struts at both ends allowing for a reliable guiding and alignment of the test tube when inserting the test tube as well as for a reliable restoration after removal of the test tube. A reliable restoration can be ensured even when holding test tubes with a larger diameter. Hence, a subsequent test tube with a smaller diameter can be retained without play.

The centering fingers can be evenly distributed about a circumference of a retaining area. The bar code, or other identification, provided at the outside of the tube can remain readable by humans or machines. The centering fingers, in particular, the resilient elements of the centering fingers of one test tube carrier in one embodiment can differ in design. In some embodiments, all centering fingers can be identical in design within tolerances and the centering fingers can be evenly distributed in order to ensure a reliable centering of the test tubes.

The resilient elements can comprise a contact portion between the first end and the second end. In some embodiments, the resilient elements can be adapted for a resilient deformation displacing the contact portion in parallel towards or away from an associated strut for receiving test tubes of different diameters. When displacing the contact portions in parallel towards or away from an associated strut, the effective contact portion in contact with received test tubes can be at least essentially the same for different test tubes of different diameters.

The resilient elements can be formed such that a contact portion of the resilient element between the first and the second end can protrude towards the central axis. In some embodiments, the contact portion can be adapted for contacting a received test tube along an interrupted or uninterrupted contact line of a defined length extending in parallel to the central axis. In the context of the present disclosure, a contact line can be defined as a contact area comprising at least two distinct contact points. It can be understood by the person skilled in the art, that the terms “line” and “point” are not to be interpreted in a strict geometrical sense. Rather, a contact area of two bodies being in point contact can be in the form of a small ellipsoid. The contact portion, for example, can be a planar contact portion extending in parallel to the central axis and contacting a test tube having a circular cross section along a contact line. In other embodiments, a contact portion having a curved surface with a curvature of opposite sign than the received test tube can be provided. The defined length of the interrupted or uninterrupted contact line in particular embodiments can be at least between about 1% and about 100% of the length of the associated strut. In some embodiments, the defined length of the interrupted or uninterrupted contact line can be at least between about 40% and about 90% and in others, between about 60% and about 80%. In one embodiment, the contact portion can comprise two or more distinct contact areas, which can be offset to one another in the direction of the central axis. A received test tube can be in point contact or in line contact with each of the contact areas. In some embodiments, the contact portion can comprise one uninterrupted planar or curved contact area extending in parallel to the central axis.

The resilient elements can be adapted for a resilient deformation displacing the contact portion, in particular the contact portion contacting a test tube along a contact line, towards or away from an associated strut such that received test tubes of different sizes can be contacted at the contact portion, in particular along the interrupted or uninterrupted contact line of the defined length in parallel to the central axis. For a parallel displacement of the contact portion, in one embodiment, a first pivot leg can be arranged between the contact portion and the first end and a second pivot leg can be arranged between the contact portion and the second end. The contact portion can be coupled to the pivot legs via hinges such as, for example, via flexure hinges. When displacing the contact portion without altering the defined length of the interrupted or uninterrupted contact line, an overall contact region in which a received test tube contacts the resilient element can be independent of the diameter of the test tube. In the context of the application, a flexure hinge can be defined as a thinned out or otherwise processed part of material connecting two bodies, i.e. the contact portion and the pivot leg, made of the same material.

In one embodiment, the second end of at least one of the resilient elements can be in sliding contact with the associated strut at the lower position. Depending on the shape of the resilient element, when receiving a test tube, the second end of the resilient element can slide upwards or downwards along the strut.

In alternative or in addition, at least one of the resilient elements can be fixedly attached to the associated strut at the lower position. When attaching the resilient elements at both ends to the strut, guiding of the test tubes upon an insertion between the centering fingers can be enhanced.

The material of the elongate, bent resilient element can be chosen suitable for allowing repeatable deformation and sufficient restoration forces. In one embodiment, the resilient element can be in the form of a wire.

In some embodiments, the resilient elements can be in the form of resilient metal band. Suitable materials can be metals such as stainless steel, brass, bronze, spring steel or other similar resilient metals. The resilient metal band can be bent to contact with its two ends the strut and to protrude from the strut towards the central axis. A portion of the metal band can function as the contact portion. The portion in particular embodiments can extend in parallel to the central axis.

In some embodiments, at least one, preferably all of the resilient metal bands can be bent to form a substantially U-shaped member having a base extending in parallel to the central axis for contacting the received test tube. The U-shaped member can have two legs and the base arranged between the legs, so that the resilient element and the strut can form a trapezoid. In some embodiments, the resilient element and the strut can form a parallelogram. The base, the first leg and the second leg can function as the contact portion, the first pivot leg and the second pivot leg, respectively. Hinges between the contact portion and the first and the second leg in one embodiment can be formed by bending or folding the resilient metal band. In addition, in one embodiment, the metal band can be thinned out in the region of bends or folds for forming flexure hinges. When inserting the test tube, an angle between the legs and the base as well as between the legs and the strut can change and the height of the trapezoid or parallelogram perpendicular to the strut can be decreased. In the case both legs are fixedly attached to the strut, the legs can be swiveled in the same angular direction. In the case the second end is in sliding contact, embodiments can be conceivable, in which the legs can be swiveled in opposite directions upon receiving the test tube.

In some embodiments, the U-shaped member can comprise a first leg attached to the upper of the associated strut. The strut and the first leg can form an acute angle. In other words, the first leg can extend from the strut toward the central axis and toward the base body. When arranging the first leg at an acute angle, the first legs can form an insertion aid for the test tubes causing pre-alignment of the test tubes with the central axis.

As mentioned above, the legs, the base and the strut can form a trapezoid. In some embodiments, the U-shaped member can comprise a second leg extending in parallel to the first leg. In other words, the legs, the base and the strut can form a parallelogram. Both legs can be swiveled towards the strut upon the insertion of a test tube.

In one embodiment, the base of the U-shaped member can be bent to form a contact portion with at least two distinct contact areas. Thereby, a total area of a contact portion between the test tube and the base can be decreased.

In one embodiment, the test tubes can be placed on a flat base body and retained only by the centering fingers. In some embodiments, the base body can have a recess such as, for example, a chamfered recess adapted for accommodating a bottom of a test tube. The size or depth of the recess and an orientation of the walls of the recess can be chosen to allow for an accommodation of different types of test tubes without hindering a readability of the bar code, or any other type of identification code, provided on an outside of the test tube.

In one embodiment, the struts can be fixedly attached to the base body such as, for example, by soldered, welded, or clued to the base body. In some embodiments, at least one of the struts can be releasably attached to base body. Hence, the central fingers can be replaced if worn-out, without the necessity to replace the base body. In some embodiments, a plug-in connection can be provided. The struts can be inserted into receiving openings extending in the axial direction of the struts. The ends of the struts can be inserted into the receiving openings and the receiving openings in one embodiment do not have rotation symmetry to ensure an insertion of the struts with a suitable orientation.

A laboratory distribution system can be provided having a number of test tube carriers. The laboratory distribution system in one embodiment can comprise a transport device with a transport plane adapted to carry the number of test tube carriers. The carriers can each comprise at least one magnetically active device. The transport device can comprise a number of electromagnetic actuators. The electromagnetic actuators can be stationary arranged below the transport plane and can be adapted to move a test tube carrier placed on top of the transport plane by applying a magnetic force to the test tube carrier. However, the present disclosure may not be limited to such a laboratory distribution system. In other embodiments, for example a conveyer belt or guiding rails can be provided for moving the test tube carriers. In still another embodiment, each test tube carrier can be provided with a drive motor.

A laboratory automation system with a number of pre-analytical, analytical and/or post-analytical stations and with a distribution system having a number of test tube carriers can also be provided.

FIGS. 1 and 2show a top view and a sectional view of a first embodiment of a test tube carrier1for transporting test tubes (not shown inFIGS. 1 and 2) in a laboratory distribution system of a laboratory automation system.

The test tube carrier1can comprise a base body2and three centering fingers3attached to the base body2. The three centering fingers3can be evenly distributed about a central axis A. In other embodiments, more than three centering fingers3can be provided, for example, four or five centering fingers3. In the embodiment shown, the base body2can have a circular cylindrical shape, which can be concentric to the central axis A. However, this shape is to be understood only as an example, other shapes are conceivable. The base body can be adapted to the requirements of a laboratory distribution system.

The base body2can have a chamfered recess20, which can be concentric to the central axis A and adapted for accommodating a bottom of a test tube.

The centering fingers3can each comprise an elongate, bent resilient element30and a strut32. Due to material differences and/or due to a shape, the strut32can have a higher stiffness than the resilient elements30.

The three struts32can each extend in parallel to the central axis A. A connection of the struts32to the base body2is depicted only diagrammatically. A suitable connection can be chosen by the person skilled in the art. In one embodiment, the struts32can be releasably attached to the base body2allowing a replacement of the struts32in case the centering fingers3are worn-out.

In the embodiment shown, the resilient elements30can be in the form of bent resilient metal bands such as, for example, bent spring steel bands. A first end300of the resilient metal band can be fixedly attached to the strut32at an upper position320, which the upper position320can coincide with the upper end of the strut32. A second end302of the resilient metal band can contact the strut32at a lower position322, which the lower position322can be situated between the base body2and the upper position320.

The struts32can be arranged outside of a retaining area for the test tubes and the resilient elements30. In one embodiment, a contact portion of the resilient elements30provided between the first end300and the second end302can protrude from the struts32towards the central axis A and into the retaining area for the test tubes.

In the embodiment shown, the resilient metal bands provided as the resilient elements30can be bent to form a substantially U-shaped member having base304, a first leg307and a second leg308, each.

The base304of each of the U-shaped members can function as the contact portion. It can extend in parallel to the central axis A for contacting the received test tube (not shown) along a contact line. The first legs307of each of the U-shaped members can be attached to the strut32at the upper position320. The strut32and the first leg307can form an acute angle. Thereby, the first legs307can function as an insertion aid for a pre-alignment of the test tubes.

In the embodiment shown, the second leg308can extend substantially in parallel to the first leg307. A free end of the second leg308can contact the strut32at the lower position322.

When inserting a test tube between the centering fingers3, the resilient elements can be resiliently deformed for receiving test tubes of different diameters. The first leg300and the second leg302can be pivoted towards the associated strut32for displacing the base304in parallel towards the associated strut32. Thus, the base304functioning as a contact portion contacts can receive test tubes of different diameters along a contact line. The length LCLof the contact line can be the same for test tubes of different diameter. In the embodiment shown inFIG. 2, the length LCLof the uninterrupted contact line can be between about 70% and 80% of the length LSof the associated strut32. After removal of the test tube, the restoration force of the resilient element30can cause the first leg300and the second leg302to be pivoted away from the associated strut32for displacing the base304in parallel away from the associated strut32.

FIG. 3shows detail of the section III ofFIG. 2. As can be seen inFIG. 3, in the embodiment shown inFIGS. 1 to 3, the second ends302of the resilient elements30, more particular of the second legs308, can be in sliding contact with the associated strut32at the lower position322.

FIG. 4shows a detail of a second embodiment of a test tube carrier similar toFIG. 3. The test tube carrier according to the second embodiment in large parts can correspond to test tube carrier shown inFIGS. 1 to 3. In contrast to the embodiment shown inFIG. 3, the second end302of the resilient element30shown, preferably of all resilient elements, can be fixedly attached to the associated strut32at the lower position322.

FIG. 5shows a sectional view of a third embodiment of a test tube carrier1similar toFIG. 2. The test tube carrier1according to the second embodiment in large parts can correspond to test tube carrier1shown inFIG. 1 to 3 or 4and for a detailed description, reference is made to the above description. In contrast to the embodiments described above, the base304of the U-shaped member can be bent to form a contact portion with at least two distinct contact areas305,306, contacting the received test tube at two distinct areas. A test tube inserted between the centering fingers3shown inFIG. 5can contact the contact portion along an interrupted contact line, which can extend across both contact areas305,306. In the embodiment shown inFIG. 5, the length L305, L306of each the two distinct contact areas can be between about 5% and 10% of the length LSof the associated strut32. The overall length LCLof the interrupted contact line can be between about 70% and 80% of the length LSof the associated strut32.

FIG. 6shows a perspective view of a laboratory distribution system4comprising a number of test tube carriers1and a transport device with a transport plane6adapted to carry the number of test tube carriers1. Test tubes5can be received by the test tube carriers1and moved over the transport plane6to a desired destination.