Tube closing apparatus

Abstract

Tube closing apparatus 200 for closing one or more tubes 250 with caps attached thereto, particularly related to biological laboratory tubes for copying DNA, comprises a base 210, at least one receptacle for receiving the tube(s), the tube(s) comprising a first tube; a carriage 220 comprises an angled surface 222 and a closing element 224, the carriage linearly slides along a translation axis with respect to the base, the angled surface extends at an oblique angle with respect to the translation axis, translation of the carriage in a first direction along the translation axis brings the angled surface into contact with the attached cap to bring the attached cap closer to an open end of the first tube, continued translation of the carriage in the first direction brings the closing element into contact with the cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. The closing element may be a roller, and a further locating roller (326, fig 3A) may be provided. A tube closing apparatus with two closing means, a tube closing apparatus with a moveable element are also provided.

Description

This disclosure relates to a tube closing apparatus, and in particular to a tube closing apparatus for closing a tube having a cap attached thereto, for example the tubes forming part of a tube strip. Background Tubes are used in many fields, and in particular scientific research. Such tubes often come with caps which are attached to the tube via a flexible connector, to enable quick and easy opening and closing of the tube. These tubes often also come in "strips”, where a number of tubes are connected together via rigid or semi-flexible connectors, such as the 8-tube strips shown in figures 1A-1C. As an example, the tubes may be sized and designed for use in polymerase chain reaction (PCR) applications. However, at present, there is no quick and convenient way to close these tubes. This introduces problems for people working in laboratories, e.g. in fields such as chemistry, molecular biology, as well as more general biological applications. Researchers and users must close each tube individually by hand, which is time-consuming and inefficient The scale of this issue can be appreciated when considering that many laboratory machines have a sample capacity of hundreds of wells for receiving such tubes. Closing each tube individually by hand may also introduce a contamination risk. The issue is complicated by the fact that many tube strips used for scientific research, for example those typically employed in molecular diagnostic applications, have caps and flexible connectors which extend from the tube at a non-perpendicular angle from the tube relative to a ‘strip axis’, i.e. the axis along which the tubes are joined. This can best be appreciated by inspection of figure IB. This angled placement increases stacking efficiency of the strips, for example when the strips are placed side-by-side in a 9 6-well tube rack next to other strips, but makes the process of closing each tube more time-consuming since each tube must essentially be closed individually. The present invention seeks to address these and other disadvantages encountered in the prior art by providing a tube closing apparatus. Summary According to an aspect, there is provided a tube closing apparatus for closing one or more tubes with caps attached thereto. The apparatus comprises a base comprising at least one receptacle for receiving the one or more tubes. The one or more tubes comprise a first tube. The tube closing apparatus further comprises a carriage comprising an angled surface and a closing element, wherein the carriage is configured to linearly slide along a translation axis with respect to the base. The angled surface extends at an oblique angle with respect to the translation axis such that, when the first tube is positioned, in an open configuration, in the at least one receptacle, translation of the carriage in a first direction along the translation axis brings the angled surface into contact with the attached cap to bring the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube relative to the open configuration. The closing element is configured such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. Optionally, the angled surface is a first angled surface, and the carriage further comprises a second angled surface positioned in between the first angled surface and the closing element Optionally, the first angled surface and the second angled surface form part of a plurality of angled surfaces which define a continuously curved surface. Optionally, the oblique angle is a first oblique angle, and the second angled surface extends at a second oblique angle with respect to the translation axis such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the second angled surface into contact with the attached cap, thereby bringing the attached cap from the first configuration to a second configuration, wherein the attached cap is closer to the open end of the first tube when in the second configuration compared to the first configuration. Optionally, the first angled surface and the second angled surface are configured such that translation of the carriage in the first direction causes the attached cap to slide along the first angled surface until it is positioned in the first configuration, and slide along the second angled surface until it is positioned in the second configuration. Optionally, the closing element is a roller configured to contact the attached cap and roll across a top surface of the attached cap as the carriage is translated along the translation axis, thereby pressing the attached cap into the open end of the first tube to close the first tube. Optionally, the carriage further comprises a locating element The locating element may be configured such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the locating element into contact with the attached cap, thereby locating the attached cap into the open end of the first tube. The closing element may be further configured such that continued translation of the carriage in the first direction after the attached cap has been located in the open end of the first tube brings the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. Optionally, the locating element is positioned at a first height above the base, and the closing element is positioned at a second height above the base, where the second height is less than the first height. Optionally, the locating element is a locating roller comprising an annular chamfered edge, wherein the locating roller is positioned such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the annular chamfered edge into contact with the attached cap, thereby locating the attached cap into the open end of the first tube. Optionally, the base comprises a plurality of receptacles for receiving a tube strip, wherein the tube strip comprises a plurality of tubes comprising the first tube, and wherein each tube of the plurality of tubes comprises a respective attached cap. Optionally, each of the plurality of receptacles is positioned in a row parallel to the translation axis. Optionally, the base further comprising a lever configured to pivot about an axis perpendicular to the translation axis; the lever comprising a first end positioned underneath the at least one receptacle, and a second end wherein the lever is configured such that, when the first tube is positioned in the open configuration in the at least one receptacle, pressure applied to the second end causes the lever to pivot about the axis and push on an underside of the first tube. Optionally, the second end is positioned such that translation of the carriage in a second direction along the translation axis brings the carriage in contact with the second end, thereby applying pressure to the second end. Optionally, the plurality of receptacles comprises a first receptacle for receiving the first tube, and wherein the first receptacle comprises an inner surface which, in use, contacts the first tube; wherein the inner surface of the first receptacle comprises constraining structure configured to constrain the first tube within the first receptacle. The inner surface may take the form of an inner wall, e.g. an annular inner wall, for example. Optionally, the tube strip comprises an end tube positioned at the opposite end of the tube strip to the first tube, wherein the plurality of receptacles comprises an end receptacle for receiving the end tube, and wherein the end receptacle comprises an inner surface which, in use, contacts the end tube; wherein the inner surface of the end receptacle comprises loosening structure configured to loosen the end tube within the end receptacle. The inner surface may take the form of an inner wall, e.g. an annular inner wall, for example. According to an aspect, a tube closing apparatus is provided. The tube closing apparatus is for closing one or more tubes with caps attached thereto, and comprises a base comprising at least one receptacle for receiving at least a first tube of the one or more tubes; and a carriage comprising a first and a second closing means, wherein the carriage is configured to slide along a translation axis with respect to the base. The first closing means extends at an oblique angle with respect to the translation axis such that, when the first tube is positioned in an open configuration in the at least one receptacle, translation of the carriage in a first direction along the translation axis brings the first closing means into contact with the attached cap to bring the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube relative to the open configuration. The second closing element is positioned and configured such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the second closing means into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. According to an aspect, a system is provided which comprises a tube closing apparatus as described herein, and a first tube comprising an attached cap. Optionally, the tube may be positioned in a receptacle of the base. According to an aspect, a method of closing one or more tubes with caps attached thereto using a tube closing apparatus is provided. The tube closing apparatus is a tube closing apparatus according to any of the disclosed implementations, and comprises a base and a carriage. The method comprises positioning a first tube comprising an attached cap in a receptacle of a base, sliding the carriage along a translation axis with respect to the base, wherein the carriage comprises an angled surface and a closing element, the angled surface extending at an oblique angle with respect to the translation axis. The method further comprises continuing to translate the carriage in the first direction to bring the angled surface into contact with the attached cap, thereby bringing the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube, and continuing to translate the carriage in the first direction after the attached cap has been brought into the first configuration, to bring the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. Optionally, the angled surface is a first angled surface and the oblique angle is a first oblique angle, wherein the carriage further comprises a second angled surface positioned in between the first angled surface and the closing element, and the second angled surface extends at a second oblique angle with respect to the translation axis. The method may further comprise continuing to translate the carriage in the first direction after the attached cap has been brought into the first configuration to bring the second angled surface into contact with the attached cap, thereby bringing the attached cap from the first configuration to a second configuration, wherein the attached cap is closer to the open end of the first tube when in the second configuration compared to the first configuration. The method may further comprise continuing to translate the carriage in the first direction after the attached cap has been brought into the second configuration, to bring the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. Optionally, the carriage further comprises a locating element, and the method further comprises continuing to translate the carriage in the first direction after the attached cap has been brought into the first configuration to bring the locating element into contact with the attached cap, thereby locating the attached cap into the open end of the first tube. The method may further comprise continuing to translate the carriage in the first direction after the attached cap has been located in the open end of the first tube to bring the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. According to an aspect, a computer readable medium having data stored thereon representative of the tube closing apparatus of any of claims 1 to 16, the data being such that it can be relayed to an additive manufacturing device to enable the additive manufacturing device to fabricate the tube closing apparatus based on the data. Figures Specific embodiments are now described, by way of example only, with reference to the drawings, in which: Figures la-c depict a tube strip which may be used in conjunction with a tube closing apparatus according to the present disclosure; Figures 2a-d depict a first implementation of a tube closing apparatus according to the present disclosure; Figures 3a-b depict a second implementation of a tube closing apparatus according to the present disclosure; Figures 4a-d depict a carriage of the second implementation of a tube closing apparatus according to the present disclosure; Figures 5a-b depict a close up view of a plurality of receptacles in a base of the second implementation of a tube closing apparatus according to the present disclosure; Figures 6a-b depict a third implementation of a tube closing apparatus according to the present disclosure; Figure 7 depicts a top-down view of a fourth implementation of a tube closing apparatus according to the present disclosure; and Figure 8 depicts a view of a carriage which may be used in conjunction with a fifth implementation of a tube closing apparatus according to the present disclosure; Figure 9 depicts an implementation in which the receptacles are moveable toward a closing element, in accordance with a sixth implementation according to the present disclosure. Detailed Description In overview, and without limitation, the application discloses an apparatus for closing at least one tube. The apparatus can be configured to close a plurality of tubes, for example the tubes of a test strip, much more quickly than is possible by hand, and is particularly well-suited for closing tube strips of the type and design shown in figures 1A-1C. The apparatus comprises a base comprising at least one receptacle, into which can be placed an open tube. In this open configuration, the cap may be hinged open from the tube at substantially 180°, for example. A slideable carriage comprising an angled surface and a closing element such as a roller can then be moved toward the tube. The carriage and base are configured in such a way that, as the carriage moves toward the open tube, the angled surface contacts the cap of the tube, bringing it closer to an open end of the tube, thereby preparing the cap for contact by the closing element As the carriage is slid toward and then over the tube, the dosing element presses the cap into the open end of the tube, thereby closing it. By positioning multiple receptacles in a row, a tube strip can be positioned in the base, and the carriage can be slid toward and over each of the tubes, thereby efficiently closing all the tubes in a single movement In general, the presently disclosed tube closing apparatus in its various implementations is designed to bring the cap of a tube doser to the open end of the tube in a multi-stage process. This ensures the tube is closed in an easy, quick, and efficient manner, while avoiding damage to either the tube or the cap. Figures 1A-C depict a tube strip 100. Tube strips of this type have many applications, particularly in laboratories, and for example are suitable for molecular diagnostic and / or molecular amplification reactions. Figure 1A shows an 8 tube strip 100 with each of the tubes open. Figure lb depicts the same strip 100 from above. Figure IC depicts the same tube strip with each tube of the strip 100 closed. Figure lb also depicts the direction of a "strip axis” 151 in addition to a ‘cap axis’ 152. The strip axis 151 is the axis along which the tubes are lined to form the tube strip 100. As can best be appreciated from figure 2b, the tube strips 100 comprise connecting structure 110 between each tube which defines the strip axis 151. The cap axis 152 is the axis along which the caps extend from the strip axis 151 when the tubes are in an open configuration. There is a flexible connector, which may comprise a hinge, which connects each tube and its respective cap, and which defines the cap axis for each tube. The angle between the strip axis and the cap axis for the tube strip 100 is denoted as ip, In many commercial tube strips, the caps and flexible connectors are angled at roughly 45° with respect to the strip axis 151, i.e. ip is roughly 45°. Figures 2a-2d depict a tube closing apparatus 200 in accordance with the present disclosure. Figures 2a and 2d show a side view, figure 2b depicts the tube closer 200 from above, and figure 2c is an angled view from the back of the apparatus 200. Figures 2b and 2d demonstrate two angles 0i and 02 that define the angled surface 222 of the apparatus 200. The tube closing apparatus 200 comprises a base 210, and a carriage 220. The base 210 comprises a plurality of receptacles for receiving a tube strip 250. The apparatus 200 is depicted in figures 2a and 2c with a tube strip 250 positioned in the base, i.e. with each of the eight tubes of the tube strip 250 positioned in a corresponding hole in of the eight holes in the base 210. Figures 2b and 2d depict the same tube closing apparatus 200 without the tube strip 250 positioned in the base 210. The base 210 comprises a central section 214. Two grippable portions 216 extend outwardly from the central section 214. The grippable portions 216 take the form of flanges which extend out from a lower or bottom portion of the central section 214. A primary purpose of the grippable portions 216 is to ensure the apparatus 200 can stand upright in a stable manner. In use, a user can grip these portions to hold the base 210 still, and to facilitate relative movement between the base 210 and the carriage 220. The receptacles are positioned in a line along a longitudinal axis of the base 210, and in particular along a longitudinal axis of the central section 214. The receptacles may take the form of suitably sized holes or channels. The number of receptacles may be adjusted according to the use case, e.g. depending on the number of tubes in a tube strip, the number of strips to be closed, or depending on the number of single tubes desired to be closed in one movement, in a manner which will be explained below. The receptacles are configured such that the open ends of the tubes sit reasonably parallel with an upper surface of the base 210. For example, the receptacles may have a depth which is substantially equal or slightly less than the length of the tubes, or else the receptacles might be sized such that either the upper rim of each tube or the connecting structure 110 which joins each tube in the strip sits against an upper surface of the receptacle and / or base 120. The apparatus 200 further comprises a carriage 220. The carriage 220 comprises an angled surface 222 and a closing element 224. The carriage further comprises a channel 225. The channel may take the form of a groove or longitudinal aperture. The channel is positioned within the base of the carriage 220 and extends along a longitudinal axis of the carriage 210. The channel 225 is suitably sized, positioned and configured such that the central portion 214 of the base 210 may be positioned within the channel 225, which enables the carriage 220 to be located and positioned with respect to the base 210 in the manner depicted in figures 2a-2d. The channel 225 may therefore be described as a locating channel. The central portion 214 of the base 210, together with the channel 225 of the carriage 220, defines a translation axis 232 along which the carriage 220 can be translated relative to the base 210. Both the central portion 214 and the channel 225 extend in a longitudinal direction to define the translation axis 232. In other words, by virtue of the channel 225, the carriage 220 is configured to linearly slide along the translation axis 232 defined by the base 210.When a tube strip 250 is positioned in the apparatus 200 in the manner depicted in figures 2a-d, it will be appreciated that the strip axis, i.e. the axis along which the tubes of the tube strip 250 are positioned, aligns with the translation axis 232. The carriage 220 is moveable in a first direction along the translation axis 232 (with respect to figures 2a-2d, this first direction is substantially toward the tube strip 250), and in a second, opposite direction along the translation axis 232 (with respect to figures 2a-2d, this first direction is substantially away from the tube strip 250). The carriage 220 may therefore be positioned anywhere along the translation axis 232 between the fully ‘retracted’ position depicted in figures 2a-d, and a fully extended position (not depicted) in which the carriage 220 is e.g. located over the tube strip 250, or is at the opposite end of the base 210 having passed over the tube strip 250 . The angled surface 222 of the carriage 220 is positioned at a front end of the carriage 220. When the carriage 220 is in a retracted position, as depicted in figures 2a-d, the angled surface is positioned at an end of the carriage 220 that is closest to the receptacles in the base 210. The angled surface 222 is positioned ata first angle 0i, preferably an oblique angle, with respect to the translation axis 232. In other words, the angled surface forms an oblique angle when measured with respect to the translation axis 232. In the specific implementation depicted in figures 2a-d, the angled surface 222 is positioned at roughly a 45° angle with respect to the translation axis 232. Consequently, when a tube strip 250 is positioned in the apparatus 200, the angled surface 222 is positioned at a roughly 45° angle with respect to the strip axis of tube strip 250. The angled surface 222 is positioned at a second angle 02, preferably an oblique angle, with respect to a vertical axis 234. Each tube has a length axis, which may be described as a tube axis, since the receptacles are configured to hold the tubes in an upright manner the vertical axis 234 is parallel with the tube axes. In other words, the angled surface forms an oblique angle when measured with respect to the tube axes (or, equivalently in this implementation, the vertical axis 232). In the specific implementation depicted in figures 2a-d, the angled surface 222 is positioned at roughly a 45° angle with respect to the vertical axis 234. Consequently, when a tube strip 250 is positioned in the apparatus 200, the angled surface 222 is positioned at a roughly 45° angle with respect to the strip axis of tube strip 250. The angled surface 222 extends outward with respect to the carriage 220 in a direction with a downward component. In other words, the angled surface 222 extends both out and down from a first side of the carriage 220. The downward component of extension of the angled surface 222 is perhaps best appreciated by inspection of figure 2c. In figures 2a-d, the angled surface 222 is comprised on a cylindrical rod which is affixed or otherwise attached to the carriage 220, however the angled surface may be comprised on any of several different structural elements as will be appreciated by inspection of the other figures and will be explained in the below text. The carriage 220 further comprises a closing element 224. In the implementation depicted in figures 2a-d, the closing element 224 takes the form of a roller, however the closing element 224 may take several forms, some of which are described below. The closing element 224 is positioned such that, as the carriage 220 is translated with respect to the base 210, the closing element 224 passes over an upper end of each receptacle in turn. The gap between the closing element 224 and an upper surface of the base 210 is very small. The apparatus 200 is suitable, and configured, for closing each tube of the tube strip 250 in turn. To use the apparatus 200, a user ensures the carriage 220 is in a retracted position, with the carriage 220 not covering the receptacles. The user then positions a tube strip 250 in the base 210. The tube strip 250 is positioned within the base in such a manner that the open ends of the tubes, i.e. the ends from which the attached caps extend from, are reasonably parallel with an upper end of the base 210, for example as the connecting structure linking the tubes rests on an upper surface of the base 210. This bring the apparatus to the configuration depicted in figures 2a and 2c. The user then slides the carriage 220 along the translation axis 232 in a first direction toward the tube strip 250. In particular, the user slides the carriage 220 toward the tube strip 250 such that the angled surface 222 and closing element 224 are moved toward the tube strip 250. Translation of the carriage 220 in the first direction brings the angled surface 222 into contact with the attached cap of a first tube of the tube strip 250. Because the angled surface 222 forms an oblique angle 0i with the translation axis 232, as the angled surface 222 moves in the first direction along the translation axis 232 the cap is brought closer to the first tube, and in particular the first tube is brought closer to a closed configuration. As the carriage 220 continues to move along the translation axis 232, the closing element 224 is also brought into contact with the cap of the first tube. Following contact with the angled surface 222, the cap is almost in a closed configuration. The closing element 224 contacts the top of the cap and, as it is moved along the translation axis, presses the cap into the first tube, closing it In the implementation depicted in figures 2a-d, the closing element 224 takes the form of a roller. In this implementation, once the cap has been brought closer to the open end of the first tube, the roller rolls over the top of the cap, pressing it tightly against the open end of the first tube, thus closing it. To facilitate this closing action, the receptacles are sized and configured, and the roller is sized and positioned, such that there is a very small gap between the top of the tubes and the roller as the roller passes over the tubes. To close all the tubes in the tube strip, the user simply continues to move the carriage 220 in the first direction. The angled surface 222 meets each cap of each tube in turn, bringing the caps closer to the open ends of the tubes, and thereby bringing each tube closer to a closed configuration. The closing element 224 follows the angled surface 222 and presses the top of each cap into each tube in turn, thereby closing each tube. By translating / sliding the carriage 220 along the base and over each tube, each tube of the strip can be closed in a quick, easy, and efficient manner. In an implementation, the base 210 is configured such that the open ends of the tubes sit at a small ‘resting height' above the upper surface of the base 210. For example, the receptacles of the base 210may be sized, shaped and / or positioned in such a way that the connecting structure 110 between each tube of the strip rests against an upper surface of the base 210. This small resting height at which the upper surface of each tube of the strip sits above the base 210 can be appreciated by inspection of figure 2a. A distance between a lower surface closing element 224 and the upper surface of the base 210 may be roughly equal to, or preferably slightly less than this resting height. This means that, as the closing element 224 is moved in use over the tubes after the angled surface 222 has positioned the caps loosely in the open ends of each tube, the closing element 224 compresses the caps and tubes and presses the caps firmly into the tubes. The tubes are resilient and undergo plastic deformation as the caps are pressed downward, by the closing element 224, into the tubes, and therefore neither the tubes nor the caps are damaged by this compression. The tube closing apparatus 200 is advantageous. To date, there has been no method of closing multiple tubes in a tube strip in a single, easy and time-efficient manner. This functionality is enabled by making use of a multi-stage process to close the tubes: first the angled surface 222 is brought into contact with the attached cap of the tube, bringing it closer to an open end of the tube, and subsequently the closing element is brought into contact with the cap, pressing the cap into the open end of the tube in order to close it. Making use of a multi-stage process in this way, and in particular by making use of a process in which the cap is brought closer to the open end before it is pressed closed, also makes the closing action smooth for the user. It also prevents the tubes from jamming or otherwise preventing the carriage from moving along the translation axis, and prevents damage to either the caps or the tubes as the tubes are closed. In addition, the multi-stage process, and in particular the use of an angled surface 222, mitigates the horizontal force applied by the carriage 220 to the tubes. This horizontal force might otherwise damage the tubes or force the tube strip out of the base 210. Figures 3a and 3b depict another implementation of a tube closing apparatus 300. Apparatus 300 is depicted with a tube strip 350 in place. Figures 4a, 4b and 4c depict the carriage 320 of the same implementation of the apparatus 300. Where appropriate, like reference numerals are used for like components with regard to the apparatus 200 of figures 2a-d as apparatus 300 of figures 3a-b and the carriage of figures 4a-d. As with apparatus 200, tube closing apparatus 300 comprises a base 310 for receiving one or more tubes, a carriage 320 which is translatable with respect to the base 310, an angled surface 322 and a closing element in the form of a roller 324. The structure and functionality of the apparatus 300 of figures 3a-b is broadly similar to the structure and functionality of the apparatus 200 of figures 2a-d, however apparatus 300 has a number of additional features. In particular, apparatus 300 comprises a second angled surface 328, a locating element 326, a cutout region 355 to facilitate entry and removal of tubes into the base 310, and the slideable relationship between the carriage 320 and the base 310 is defined by a guiding rail 313 formed on the base 310. The carriage 320 comprises a plurality of angled surfaces, comprising at least a first angled surface 322 and a second angled surface 328. The second angled surface 328 is positioned in between the first angled surface 322 and the closing element 324. In figure 4c, a 'strip axis’ 351 is depicted. This strip axis 351 is the axis along which the receptacles of the base 310 are formed, and along which each tube in a tube strip will sit. As can be seen in figures 4c and 4d, the first angled surface 322 forms a first oblique angle 0i with respect to the translation axis (or, equivalently, with respect to an axis parallel to the translation axis such as the strip axis 351). The second angled surface forms a second oblique angle 03 with respect to the translation axis (or, equivalently, with respect to an axis parallel to the translation axis). The second oblique angle 03 is greater than the first oblique angle 0i Both the first angled surface 322 and second angled surface 328 are formed on an extending member which extends from a main body of the carriage 320. The first angled surface 322 is formed on a wedge-shaped portion of the extending member, and the second angled surface 328 is formed on a cylindrical portion of the extending member. The first angled surface 322 and the second angled surface 328 are configured such that, as the carriage is moved in the first direction toward the tubes, the caps of each tube are first contacted by the first angled surface 322, and subsequently by the second angled surface 328. Translation of the carriage 320 in the first direction causes an attached cap of a tube to slide first along the first angled surface 322 until it is positioned in a first configuration (i.e. a first position). In the first configuration I position, the cap is closer to the open end of the tube. Continued translation of the carriage 320 brings the second angled surface 328 into contact with the cap while it is in the first configuration. The cap can then slide along the second angled surface 328 while the carriage 320 is being translated until it is brought to a second configuration / position, in which it is even closer to the open end of the tube. The angles of the first and second angled surfaces dictate the rate at which the cap is brought closer to the open end of the tube as the carriage 320 is translated. An advantage of providing two angled surfaces in this manner, in particular two angled surfaces which meet the caps at two different angles 0i and 03, is that each cap can be brought toward the open end of its tube in a smooth and controlled manner. Further, the horizontal force which would otherwise impact the caps as the carriage is translated is mitigated by the angled surfaces, thereby reducing the chances of damaging the tubes and / or the caps, or dislodging the tube or tube strip from the base 310. Further, the use of two angled surfaces, with the second angled surface 328 forming a greater angle 03 with respect to the strip axis 351 in this manner, makes good use of available space and means that the extending member on which the angled surfaces are formed needs to extend outward less far from a main body of the base 310. The two angled surfaces also guide the caps so that they are better positioned to be contacted by the locating element 326, as will be discussed below. In addition, the provision of a plurality of angled surfaces in the manner described is beneficial in a scenario in which the tubes of the tube strip are new and have not been used yet For new tube strips, the hinge is initially flat (180 degrees open) and stiff since it has never been flexed. The gentler initial angle of the first angled surface is less aggressive, and creates the initial bend from 180 (or in some cases, more than 180) to an angle substantially less than 180. Once in this position, the hinge(s) have been creased or deformed sufficiently that it is safe to be more aggressive, which allows for the use of the second, sharper angle of the second angled surface. Using two angles, rather than just a single less aggressive ‘safe’ angle, means a greater degree of angular translation of the cap (from an open toward a closed configuration) can be achieved for a shorter translation distance of the carriage 220. In the depicted implementation, the locating element takes the form of a locating roller 326. The locating roller 326 is configured such that continued translation of the carriage 320 in the first direction after the attached cap has been brought into the first configuration (after contact with the first angled surface 322) and then the second configuration (after contact with the second angled surface 328) brings the locating roller 326 into contact with the attached cap. The locating roller 326 is configured to contact the attached cap of a tube while it is in the second configuration, thereby locating it within the open end of the tube. To accomplish this function, the locating roller 326 is positioned between the first angled surface 322 and the closing element 324. More specifically, the locating roller 326 is positioned between the second angled surface 328 and the closing element 324. The locating roller 326 is configured and positioned such that, as the carriage 320 moves in the first direction, a cap slides along the second angled surface 322 and then immediately contacts the locating roller 326. The cap is moved downward toward the open end of its tube as the locating roller 326 rolls I rotates, such thatthe cap is moved to a located configuration (i.e. a located position), i.e. a configuration / position in which the cap is located within an open end of its tube. In the 'located position’, the cap is in contact with the open end of the tube, but has not yet been pressed down firmly so as to close the tube. The locating roller 326 may comprise a chamfered edge 327. The chamfered edge 237 extends around a circumference of the locating roller 326 and may be referred to as an annular chamfered edge 327. The edge may be chamfered at a 45°angle, for example. The locating roller 326 is configured and positioned such that continued translation of the carriage in the first direction brings the annular chamfered edge into contact with the attached cap, thereby locating the attached cap into the open end of the first tube. This functionality is advantageous, as it ensures the cap is well-positioned for the closing element 324 to come along and press the caps into the tubes, thereby firmly closing the tubes. In particular, the locating roller 326 is positioned such that, as the carriage 320 slides in the first direction, it is the chamfered edge 327 of the locating roller 326 which is the first part of the locating roller 326 which contacts the caps of the tubes. In the implementation shown, the chamfered edge 327 contacts the caps as they slide off the second angled surface 328. As the carriage is moved along the translation axis, the chamfered edge 327 applies a force vector to the caps which causes the caps to locate within the open end of the tubes. In a particular implementation, the chamfered edge 327 may be chamfered at an angle i|j, e.g. at 45°. This means that, as the carriage 120 is moved along the translation axis, a force is applied to each cap which is substantially aligned with the cap axis of the tubes. As can be seen in the depicted implementation in figures 4a-c, the second angled surface 328 may be formed on an element which extends inwardly toward the locating roller 326. The element comprising the second angled surface 328 extends toward the locating roller 326, and has a surface that faces the locating roller 326 and that is shaped to match the locating roller 326. The surface may be described as a curved, or a contoured, surface. The contoured surface comprises a degree, e.g. a radius, of curvature that matches the radius of curvature of the locating roller 326. In other words, the extending element has a profile which matches or is shaped to fit with the profile of the locating roller 326. The provision of a contoured surface in this manner, e.g. that is positioned close to the outer surface of the locating roller 326 and which is shaped to align with the outer surface of the locating roller 326, reduces the gap between the second angled surface 328 and the locating roller 326, and thus provides a small gap for ingress of a cap as the carriage 320 is translated. In the absence of this contoured surface, there would be an increased risk of a cap entering a gap between the second angled surface 328 and the locating roller 326 and thus becoming caught, tangled in the mechanism, or damaged. As can be appreciated by inspection of figure 4a, the first angled surface 322, second angled surface 328, locating element 326, and closing element 324 are positioned at different heights, and in particular are configured to sit at different heights with respect to the base 310. The first angled surface 322 is positioned at a first height, which is substantially the same height as an upper surface of the base 310 upon which the receptacles are formed. This allows the first angled surface 322 to contact the caps of the open tubes, even the caps which are hinged open by 180° or more. The first angled surface 322 extends upward toward the second angled surface 328. This means that, in use, the caps are moved upward, through their hinged motion, and toward the second angled surface 328. When the caps leave the first angled surface 322 they are positioned in the first position, in which they have been moved closer toward the open end of their tubes. The second angled surface 328 is positioned at a second height, which is greater than the first height The second angled surface 328 extends upward, from the first angled surface 322, toward the locating element 326. This means that, in use as the carriage 320 is moved forward in the first direction, the caps continue to be moved upward as they slide along the second angled surface 328. The caps continue to move through their hinged motion toward the open end of the tubes. When the caps leave the second angled surface 328 they are positioned in the second configuration I position, in which they have been moved closer toward the open end of their tubes. The locating element 326 is positioned at a third height, and the closing element 324 is positioned at a fourth height The fourth height is less than the third height Since the locating roller 326 and closing element 324 are positioned at different heights, their functions are facilitated. As the caps contact the locating roller 326 and in particular the chamfered edge 327, they are moved downward as the locating roller 326 rotates, such that they are positioned in a located position to facilitate closing by the closing element 324. Again, moving the caps through their hinged motion in a multi-stage process in this way provides a smoother and more efficient closing action, reduces the chances of caps exiting the closing mechanism or tubes otherwise not being closed properly, and reduces the chances of damage to the tubes and caps. The locating element 326 reduces the risk of slippage, and reduces the chance of the cap getting caught in the mechanism. The chamfered edge also mitigates the sideways force that might otherwise damage the tubes, or force them out of the base 310. In the implementation depicted in figures 4a-c, the locating and closing elements are annular rollers, and in particular are bearings. In this implementation, the closing roller 324 may have a smaller diameter than the locating roller 328. It will be appreciated that, the smaller the diameter of a roller, the greater the degree of angular transition of the cap is effected per unit of linear translation of the carriage 320. Therefore, the larger diameter locating roller 326 is positioned to contact the caps first, since a greater degree of angular translation is required to transition the caps from their position as they leave the second angular surface 328 into a "nearly-closed” position in which the caps are located in the open ends of the tubes. The closing roller 326 then has a smaller diameter in order to effect a more ‘aggressive’ downward force to close the tubes. The larger diameter locating roller 326 is therefore configured to move the caps through the necessary degree of angular movement, but not too quickly or too aggressively, thereby preventing damage or deformation of the hinge and caps. As can be seen in figure 4c, the first angled surface 322, second angled surface 328, and locating element 326 are offset with respect to the strip axis 351. The first angled surface 322 is the most offset, in other words is offset by the greatest distance, to enable it to capture caps which are hinged open, for example which are hinged open by 180° or more. The first angled surface 322 extends inwardly toward the strip axis 351. The second angled surface 328 is offset by a lesser degree than the first angled surface 322. The second angled surface 328 extends inwardly toward the strip axis 351. This reduction in offset, and gradual extension inward toward the strip axis 351, brings the caps through their hinged motion and into a suitable position to be located within the open end of the tubes by the locating element 326. The locating element 326 is also offset with respect to the strip axis 351, such that the chamfered edge 327 contacts the caps and moves them downward, toward and into the open ends of each tube. The closing element 324 is aligned with the strip axis 351, and is configured to roll along the strip axis 351. This ensures that the caps are firmly located and closed within the open ends of each tube. Tube closing apparatus 300 comprises grippable portions 316 which extend out from a main body of the base 310, to enable a user to better hold and grip the base 310 during use of the apparatus 300. The carriage 320 comprises indentations 329, which are sized and positioned to enable better gripping of the carriage 320 by a user. The apparatus 300 further comprises a cutoutportion 355 underneath the receptacles in the base 310. The receptacles take the form of apertures through which a tube may be placed. The cut-out portion 355 enables users to simple and conveniently remove the tube strip 350 from the base 310, for example after the tubes of the tube strip 350 have been closed. The user simply uses their hands to push upwards on a bottom surface of one or more of the tubes of the tube strip 350 to loosen the tube strip 350 from the base 310. While the tube closing apparatus 200 of figures 2a-d enables linear movement of the carriage with respect to the base via a central extension 214 and a suitably shaped and positioned cavity 255, the skilled person will appreciate that linear movement may be enabled in many ways. For example, as can be appreciated from figure 3b, the base 310 of tube closing apparatus 300 may comprise a linear guide rail 313. The linear guide rail 313 defines the translation axis of the apparatus 300. The carriage 320 comprises suitable structure to interact with the guide rail 313, to enable the carriage to be slidably mounted to the guide rail 313. In addition, stoppers 315 are positioned to define the extent of the linear movement, from a fully retracted position in which the angled surface(s) are facing the receptacles, and a fully extended position in which the carriage 320 has been moved over the receptacles. The tube closing apparatus 300 is easy to use, and can be used to close many tubes in one simple sliding action. The method of operation for apparatus 300 is similar to the method of operation for apparatus 200, though nonetheless a brief description is provided to facilitate understanding. First, a user positions at least a first tube comprising an attached cap in a receptacle of a base. To close multiple tubes of a tube strip 350, the user positions the tube strip 350 in the receptacles of the base 310. The carriage 320 is in a retracted position, for example the position depicted in figures 3a and 3b. The user then grips the carriage 320, for example via the indentations 329, and slides the carriage 320 forward toward the tubes, i.e. in the first direction along the translation axis. This translation or ‘sliding' action brings the first angled surface 322 into contact with the attached cap of a first tube in the tube strip, thereby bringing the attached cap into a first configuration in which it is closer to an open end of the first tube. The cap is designed to be moved in a hinged motion, and since the angled surface 322 is angled in the manner described above, as the cap slides along the first angled surface 322 it is moved through part of its hinged motion toward the open end of the first tube. As the user continues to translate the carriage 320, the second angled surface 328 contacts the cap. The cap slides along the second angled surface 328. Since the second angled surface 328 is angled in the manner described above, the attached cap continues to move through its hinged motion from the first configuration to a second configuration. As the cap slides along the second angled surface 328, it is moved toward the second configuration, in which it is even closer to an open end of the first tube compared to the first position. When the tube is in the second position, it is well-positioned to be contacted by the locating element 326. As the user continues to translate the carriage 320 after the cap has contacted the first angled surface 322 and the second angled surface 328, the locating element 326 is brought into contact with the cap of the first tube. The cap contacts the chamfered edge, which imparts a force in a direction substantially aligned with the cap axis, thereby locating the cap into the open end of the first tube. The cap is then in the located configuration / position. As the user continues to translate the carriage 320 after the cap has contacted the first angled surface 322, the second angled surface 328 and the locating element 326, the closing element 324 is brought into contact with the cap. The closing element 324 may take the form of a roller as described above, and the roller may be aligned and centred with respect to the strip axis. Further, the closing roller 324 may be positioned at only a small height above the base. The closing roller 324 may be configured to contact the cap and roll across a top surface of the cap as the carriage is translated. The result is that; as the closing roller 324 is brought into contact with the cap while it is located within the open end of the tube, it is pressed into the open end of the first tube, thereby closing the first tube. To close each tube of the tube strip 350, the user simply continues to slide the carriage 320 along the translation axis in the first direction, bringing the cap-contacting components of the carriage 320 into contact with the caps of each tube in turn. In an implementation, as the carriage 320 moves along the translation axis, the first angled surface 322 contacts each of the caps of the open tubes in turn. While the closing element 326 is closing, for example, the first tube, the first angled surface 322 is beginning the process of moving the cap of the second, or even the third, tube from the open configuration into the first configuration in which it is closer to being closed than the open configuration. As the carriage is moved along the translation axis, each stage of the multi-stage closing process (e.g. moving caps / tubes from the open configuration to the first configuration by the first angled surface 322, moving caps / tubes from the first configuration to the second configuration by the second angled surface 328, moving caps I tubes from the second configuration to the located configuration by the locating element 326, and closing the tubes by the closing element 324) may be performed simultaneously, each on a different tube of the tube strip. This increased the speed and efficiency at which the tubes may be closed. Figures 5a and 5b depict close up views of the receptacles comprised within the base 310 of the apparatus depicted in figures 3a and 3b, and which is compatible with the carriage 320 of figures 4a-d. The base 310 comprises receptacles 311a-h. The plurality of receptacles 311a-h is positioned in a row. The row is parallel with the translation axis of the carriage such that, in use, the carriage moves over each of the receptacles as it is translated along the translation axis. Optionally, one or more of the receptacles may comprise constraining structure configured to constrain tubes positioned within the receptacles 311a-h. A primary purpose of this constraining structure is to prevent tubes of the tube strip from exiting the base 310 during use, in particular when the one or more angled surfaces impact the tubes, while also allowing the tubes to be easily removed from the base 310 by a user. The degree of constraint need not be high, as the user should still be able to remove the tube form the receptacle. In an implementation, the ‘first’ receptacle 311a, i.e. the receptacle positioned nearest to the carriage 320 when the carriage is in the retracted position shown in figures 3a and 3b and which the carriage 320 passes over first as it moves toward the tube strip in use, comprises constraining structure 312a. The constraining structure 312a may take the form of any of bumps and / or projections and / or protrusions and / or ridges on an internal surface. This structure 312a on the inside of the receptacle 311a acts to prevent the first tube of a tube strip from exiting the base 310 when it is contacted by the carriage 320. In an implementation, a subset of the receptacles 311 each comprise constraining structure, for example the first two receptacles 311a-b, or the first three receptacles 311a-c. The subset of constraining receptacles comprises the first receptacle 311a and a number of sequential receptacles, where the number is less than the total number of receptacles. Optionally, one or more of the receptacles may comprise loosening structure 319, which may for example comprise grooves extending into the internal wall of a receptacle, apertures, cut-outs, or depressions in the internal wall of a receptacle. Alternatively or additionally, the radius of the receptacles may be increased relative to the other receptacles. This ‘loosening structure’ 319 acts to prevent the last tube of a tube strip from being stuck in the base 310, in particular when a user seeks to remove the tube strip from the base 310. In an implementation, a subset of the receptacles 311 each comprise loosening structure, for example the last two receptacles 311h-g, or the last three receptacles 311f-h. The subset of these receptacles comprises the last receptacle 311h and a number of sequential receptacles, where the number is less than the total number of receptacles. The loosening structure is particularly beneficial in an implementation which comprises constraining structure 312a. In the implementation depicted in figures 5a and 5b, a user may press the underside of one or more of the tubes to remove a tube As the first, or the first few, tubes are constrained within the base 310, the user is naturally motivated to press the underside of these tubes when removing the tube strip from the base 310. However, this can impart a rotational force to the tube strip causing it to rotate as it exits the base 310, and this action may result in the tube strip becoming stuck in the base 310. The loosening structure 319f-h allows this rotating action and thereby prevents the tube strip from becoming stuck in the base 310. The base 310 may also comprise an angled ridge 321. The angled ridge 321 runs along an upper surface of the base 310 and extends therefrom. The angled ridge 321 is configured, e.g. shaped, angled and positioned, positioned, to limit the angle to which caps can open from open tubes while one or more tube strips are positioned in the receptacles 311a-h. The angled ridge 321 prevents the caps from opening beyond a maximum angle, for example the angled ridge 321 may prevent the hinges of each tube opening beyond 180°. The angled ridge 321 thereby prevents the hinges from opening too far and ensures they are in an optimal position to be contacted by tan angled surface of the carriage during use. In turn, this helps prevent damage to the tubes, hinges and caps, and ensures the tube strips are not pushed or otherwise forced out of the receptacles of the base. In an implementation of the present disclosure, the apparatus may comprise a clamping or holding mechanism or means (not shown in the figures). The clamping means is configured to hold one or more, or all, of the tubes in position during use of the closing apparatus. The clamping means is also configured to open and allow the tubes to be removed from the base after the tubes have been closed. This holding mechanism may be motorised, for example, and is controllable by a user to allow a user to clamp or release a tube strip from the base. The constraining structure, loosening structure, angled ridge and clamping means described with respect to figure 5a, 5b may be used either alone or in combination, and with any of the embodiments and implementations described herein. Figures 6a and 6b depict another implementation of a tube closing apparatus 600 according to the present disclosure. Figure 6b depicts a cross-section taken through the strip axis. With reference to the implementations described above, like reference numerals are used for like components where appropriate. The general form and function of tube closing apparatus 600 is similar or identical to that described above, in particular with respect to tube closing apparatus 300, with the addition of the lever function to facilitate removal of tube strips from the base 610 as will now be described. The base 610 of apparatus 600 comprises a lever 670. The lever 670 may be described as a ‘rocker’. The lever 670 is configured to pivot about a pivot point 673. Pivot point allows rotation of the lever 670 about an axis perpendicular to the translation axis. The lever’s 670 tilt axis is parallel with the rotation axes of the locating roller 626, the closing roller 624, and a pressure roller 623 (which is described below). The lever 670 comprises a first end 671 positioned underneath one or more receptacles in the base 610. The lever 670 further comprises a second end 672. The lever 670 is configured such that pressure applied to the second end 672 causes an upward movement of the first end via a pivoting action of the lever 670 about the pivot point 673. When a tube strip is positioned in the receptacles, pressure applied to the second end 672 causes the lever 670 to pivot about its axis and push on an underside of one or more tubes of the tube strip, thereby causing them to loosen in the base and be easier for a user to extract. The second end 672 of the lever 670 can be pressed by hand by a user, for example when they have closed the tubes of the tube strip and retracted the carriage by moving it in a second direction along the translation axis (i.e. opposite the first direction). Alternatively, the second end 672 may be configured and positioned such that translation of the carriage 620 in the second direction brings the carriage into contact with the second end 672, thereby applying pressure to the second end and causing the tilting of the lever. To facilitate this, as depicted in figure 6b, the carriage 620 may comprise a pressuring element 623. The pressuring element can take several forms, for example a pressuring roller 623. The pressuring element is configured to apply pressure to the second end 672 of the lever 670. The pressuring element 623 may be configured to slide, or roll, along an upper surface of the base 610 and / or along an upper surface of the lever 670. In this way, as the carriage is retracted after the tube(s) have been closed, the pressuring element 672 is brought into contact with the second end of the lever 672, thereby imparting an upward action to one or more tubes of the tube strip and facilitating removal of the tube strip from the base. The functionality provided by the lever 670 is advantageous as it facilitates removal of the tube strip, and also prevents manual errors which may otherwise occur, for example, in which a user applies too much force when ejecting the strip. By configured the lever 670 such that the first end 671 imparts an upward force only on the first tube of the tube strip and / or on a first subset of tubes in the tube strip in the manner depicted in figure 6a, the tube strip is not ejected straight up. This might otherwise risk the tube strip ‘jumping’ out of the base 610. Instead, the tube strip comes out at an angle, thereby preventing the entire strip from being ejected out of the base. It will be understood that the above description of specific embodiments is by way of example only and is not intended to limit the scope of the present disclosure. Many modifications of the described embodiments, some of which are now described, are envisaged and intended to be within the scope of the present disclosure. It should be noted that while the figures, and in particular figures la-c, depict tubes having a mostly flat cap, the present tube closing apparatus is compatible with a variety of tube strips, for example tubes with domed caps. In addition, while the apparatus has been described predominantly with respect to closing all the tubes of a single tube "strip” such as those depicted in figures la-c, the skilled person will appreciate that the presently disclosed apparatus is capable of closing a single tube. For example, the base may comprise only a single receptacle configured to receive a single tube. Alternatively, the apparatus may be configured to close a plurality of tube strips. The apparatus may be configured to close a plurality of tube strips in parallel, in series, or both. For example, the base may be configured to hold a plurality of tube strips in a line, along a single axis. By placing a plurality of tube strips in such a base, i.e. one with a sufficient number of receptacles, it is possible to close the tubes of each tube strip in a single translation motion of the carriage. The apparatus may be configured to hold, and close, tubes in series. Figure 7 depicts a top-down simple schematic of such a tube closing apparatus 700. The apparatus 700 comprises a base 710 which comprises a first plurality of receptacles 711a-h positioned along a first axis, and configured to receive the tubes of a first tube strip. The base 710 further comprises a second plurality of receptacles 711i-p and a third plurality of receptacles 711q-x positioned along a second and third axis respectively, and each plurality of tubes configured to receive the tubes of a respective tube strip. The tube closing apparatus 700 further comprises a plurality of carriages 720a-c. The depicted carriages 720a-c are the same, or similar, in form and function to those described above in relation to figures 4a-d and 6a, 6b. However it should be appreciated that the carriages 720a-c may take any appropriate form, shape or configuration, for example they may take the form of any of the carriages disclosed and described herein. The carriages 720a-c may be configured to translate together as a single unit, or may be individually translatable along their respective axes. Each carriage 720a-c is moveable along its own respective translation axis, and each of these translation axes may be parallel with each other. Each carriage 720a-c is slideable and translatable with respect to the base 710 in the manner described above in relation to the embodiments described in figures 1-6. In use, a user inserts a tube strip into each plurality of receptacles 711a-x while the carriages 720a-c are in the retracted position depicted in figure 7. The user may then grip the carriages 720a-c and slide them toward each tube strip such that each tube of the plurality of tube strips is closed in a single movement Any of the implementations described herein may comprise actuation means configured to actuate the carriage, or a plurality of carriages, with respect to the base. The actuation means may comprise, for example, a linear actuator. The actuation means controls the extent to which the carriage is moved along the base. In use, a user can insert one or more tube strips into the base and, by virtue of controlling the actuation means, close each of the tubes in the tube strip (s), and then return the carriage to its retracted position. For example, with respect to figure 7, the actuation means may be configured to move each of the carriages either individually or all together in order to move each carriage 720a-c with respect to the base 710. Advantageously, the presently disclosed apparatus may be used in an automated or high throughput production line, where large numbers of tubes are closed in an extremely short time. The figures primarily depict an apparatus in which a carriage is moveable, manually by a user or by actuation means, with regard to a substantially stationary base in which the tubes are held. However, this need not be the case. The skilled person will understand that it is relative movement between the cassette and base which enables the tube closing action. Therefore, in an example, the tube holding base or apparatus may be moveable with respect to a substantially stationary closing apparatus or carriage. Similarly, both components could move to effect the relative movement Figure 9 depicts an example implementation of a tube closing apparatus 900. The tube closing apparatus comprises a moveable element 910 and actuation means 990 for operating the moveable element910. The moveable element910 maybe a moveable base. The moveable element 910 may take the form of a belt, for example a conveyor belt such as a continuous conveyor belt. The moveable element 910 is configured to hold a plurality of tubes, for example via a plurality of receptacles 911a-h. The moveable element 910 moves the tubes toward a stationary element 920, which may be a head element The head element 920 is configured to close each of the tubes in turn as it contacts them. The moveable element 910 maybe sized and otherwise configured to hold the plurality of tubes, and bring the tubes into contact with the stationary element 920 in turn. The stationary element 920 may comprise, for example, any of a first and second angled surface, locating element, and closing element in the manner described above and elsewhere herein. In this manner a large number of tubes can be closed efficiently and in quick succession. In this implementation, the stationary element 920 is similar in form and function to the carriage described elsewhere herein, and the moveable element 910 is similar in form and function to the base described elsewhere herein. Since the ‘carriage’ is now stationary and positioned above the moveable element, it may be described as a head element 920. Since the ‘base’ can move, or at least is configured to move one or more receptacles 911a-h, it may be described as a moveable base, or more broadly a moveable element910. In the implementation shown in figure 9, the moveable element 910 is a conveyor belt, or a similar structure, controlled by an actuator 990, but it may take other forms, for example a slideable base element configured to slide with respect to the head element 920. The head element 920 is positioned above the conveyor belt 910. The moveable element 910 comprises at least one receptacle 911a for receiving the one or more tubes, the one or more tubes comprising a first tube. The moveable element 910 comprises receptacles 911a-h arranged in one or more lines, each configured to receive an open tube to be closed. In this example, each receptacle of the plurality of receptacles 911a-h is positioned along the translation axis, thereby defining the translation axis. The tube closing apparatus further comprises a head element 920 comprising an angled surface and a closing element, in much the same way as described above for the other implementations. The moveable element 910 is configured to move the at least one receptacle 911a-h along the translation axis with respect to the head element 920; for example via the action of the slideable base element or the conveyor belt. In a manner similar to that described elsewhere herein: the angled surface extends at an oblique angle with respect to the translation axis such that, when the first tube is positioned, in an open configuration, in the atleastone receptacle 911a, movement of the moveable element 910 in a first direction along the translation axis brings the angled surface into contact with the attached cap to bring the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube relative to the open configuration. The closing element is configured such that continued translation of the moveable element in the first direction after the attached cap has been brought into the first configuration brings the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. It should be understood that the head element 920 may comprise any of the features of the carriage described elsewhere herein, for example the first and second angled surfaces, one or more closing elements, etc; and the moveable element 910 may comprise any of the features of the base described herein, as appropriate. The tube closing apparatus may be a tube closing apparatus for closing one or more tubes with caps attached thereto, comprising a base comprising at least one receptacle for receiving the one or more tubes, the one or more tubes comprising a first tube; and a carriage comprising an angled surface and a closing element, wherein the carriage and base are configured to allow relative movement with respect to one another along a translation axis wherein the angled surface extends at an oblique angle with respect to the translation axis such that, when the first tube is positioned, in an open configuration, in the atleastone receptacle, relative movement of the angled surface in a first direction along the translation axis toward the at least one receptacle brings the angled surface into contact with the attached cap to bring the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube relative to the open configuration; and wherein the closing element is configured such that continued relative motion of the angled surface in the first direction after the attached cap has been brought into the first configuration brings the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube. While the figures of the present disclosure primarily depict a closing element, and optionally a locating element, which takes the form of a roller, and in particular the form of a bearing, these closing and locating elements may take any suitable form. For example, these components may comprise a surface geometry that enables the functionality described above. For example, with respect to figures 4a-d, the locating element 326 and closing element 324 may be formed of a low-friction material such as teflon or delrin, and may take the form of appropriately shaped protruding cylinders or bars. In other words, while the rolling action of a roller, wheel or bearing is beneficial for several reasons, it is by no means essential to the present invention. Generally speaking, carriages of the present disclosure are configured to close tubes in a multistage process. While figures 4a-d depict a carriage comprising a first and second angled surface angled surface, it will be appreciated that the carriage may comprise a greater plurality of angled surfaces, such that the cap, by coming into contact with each angled surface in turn, is brought closer toward being closed. This enables a smooth transition from an open to a closed, or to a nearly-closed, configuration. Figures 4a-d depict a carriage comprising a distinct first and second angled surface angled surface. These surfaces may be formed on an extending bar or wedge component, for example. However, the first and second angled surfaces needn’t be distinct and discrete. In an example, the extending wedge may comprise a curved surface which represents a smooth transition between a first and second angled surface. Such a curved surface would in effect comprise a plurality of angled surfaces, each with a smooth transition between them. In use, as the user slides the carriage toward the open tubes, a first angled surface of the plurality of angled surfaces contacts the cap. As the carriage continues to move along the translation axis, the cap contacts each of the plurality of angled surfaces in turn. In this manner, the curved surface smoothly brings the cap from an open configuration, e.g. in which it is 180°open, through a successive series of positions in which it is brought closer and closer to the open end of the tube, until it is brought to a position in which it is close enough to the open end of the tube to be acted upon by the locating element. Alternatively, or in addition, the functions of the various components of the carriage which contact the cap in use could be fulfilled by a single, unitary component For example, this unitary component could be a single-moulded or 3d printed component, which is shaped to comprise the one or more angled surfaces, (optionally) a locating element, and a closing element, and is thereby able to fulfil all the functions of the one or more angled surface(s), the locating element, and the closing element described above. With respect to figure 4a, for example, such a unitary component may have a lower profile / surface that follows the contour of the first and second angled surface 322, 328, the locating element 326, and the closing element 324. The component may be comprised of an anti-friction material to prevent the cap sticking to the surface as of the unitary component as the carriage is slid along the translation axis. In a further implementation of the present disclosure, each opposing side of the carriage may comprise one or more angled surfaces, a locating element and a closing element. An example of this type of arrangement is depicted in figure 8. Figure 8 depicts a carriage 820 for a tube closing apparatus, the carriage 820 comprising a first end and a second end. The carriage 820 comprises, on the first side, a first angled surface 822a, a second angled surface 828a, a locating element 826a, and a closing element 824a. The carriage comprises like components on its second side, and like reference numerals are used for like parts. These components take the form and function as described above, however the components on each side of the carriage face in opposite directions. A tube closing apparatus comprising the carriage 820 depicted in figure 8 is suitable for closing tubes more quickly and efficiently, since the carriage is configured to close tubes in both directions. In use, a user may position a tube strip in a base, and close each tube of the tube strip by moving the carriage 820 in a first direction along the translation axis. The user then needn’t move the carriage 820 back along the translation axis in order to reposition the carriage back into the retracted position before pacing another tube strip in the base. Instead, the user may simply position another tube strip in the base and move the carriage 820 in a second, opposite direction along the translation axis. In an implementation in which the tube closing process is automated, such a carriage 820 may move back and forth continuously along the translation axis while a user, or automated means such as a soft robotics solution, continuously positioning tubes in, and removing tubes from, the receptacles of the base. While the disclosure focuses on the tube closing apparatus itself, it will be appreciated that the present disclosure also relates to system which comprises a tube closing apparatus according to any of the implementations disclosed and described herein, and in addition comprises at least one tube comprising an attached cap. The tube may be positioned, for example, in a receptacle in the base. The system may further comprise a plurality of tubes, for example in the from of a tube strip as disclosed and described herein, which may be positioned in a corresponding plurality of receptacles in the base. The various implementations of the tube closing apparatus disclosed herein may be manufactured and fabricated in any of a number of possible ways. For example, the carriage and base may be 3D printed. Data, for example in the form of a model file, may be stored on a computer readable medium. The model file may be in the STL format, for example. The data is representative of the tube closing apparatus disclosed herein, and is of such a form and type that it can be relayed to an additive manufacturing device to enable the additive manufacturing device to fabricate the tube closing apparatus based on the data. Some or all of the device may alternatively be manufactured in any of a number of ways, and parts may be manufactured and shaped by injection moulding, machining, and other traditional manufacturing techniques. 5 It is to be understood that the above description is intended to be illustrative, and not restrictive. Many other implementations will be apparent to those of skill in the art upon reading and understanding the above description. Although the present disclosure has been described with reference to specific example implementations, it will be recognized that the disclosure is not limited to the implementations described, but can be practiced with 10 modification and alteration within the spirit and scope of the appended claims. Accordingly, the specification and drawings are to be regarded in an illustrative sense rather than a restrictive sense. The scope of the disclosure should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

1. A tube closing apparatus for closing one or more tubes with caps attached thereto, comprising:a base comprising at least one receptacle for receiving the one or more tubes, the one or more tubes comprising a first tube; anda carriage comprising an angled surface and a closing element, wherein the carriage is configured to linearly slide along a translation axis with respect to the base;wherein the angled surface extends at an oblique angle with respect to the translation axis such that, when the first tube is positioned, in an open configuration, in the at least one receptacle, translation of the carriage in a first direction along the translation axis brings the angled surface into contact with the attached cap to bring the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube relative to the open configuration; andwherein the closing element is configured such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube.

2. The tube closing apparatus of claim 1, wherein the angled surface is a first angled surface, and the carriage further comprises a second angled surface positioned in between the first angled surface and the closing element.

3. The tube closing apparatus of claim 2, wherein the first angled surface and the second angled surface form part of a plurality of angled surfaces which define a continuously curved surface.

4. The tube closing apparatus of claim 2 or claim 3, wherein the oblique angle is a first oblique angle, and the second angled surface extends at a second oblique angle with respect to the translation axis such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the second angled surface into contact with the attached cap, thereby bringing the attached cap from the first configuration to a second configuration, wherein the attached cap is closer to the open end of the first tube when in the second configuration compared to the first configuration.

5. The tube closing apparatus of any of claims 2 to 4, wherein the first angled surface and the second angled surface are configured such that translation of the carriage in the first direction causes the attached cap to slide along the first angled surface until it is positioned in the first configuration, and slide along the second angled surface until it is positioned in the second configuration.

6. The tube closing apparatus of any preceding claim, wherein the closing element is a roller configured to contact the attached cap and roll across a top surface of the attached cap as the carriage is translated along the translation axis, thereby pressing the attached cap into the open end of the first tube to close the first tube.

7. The tube closing apparatus of any preceding claim, wherein the carriage further comprises a locating element, wherein:the locating element is configured such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the locating element into contact with the attached cap, thereby locating the attached cap into the open end of the first tube; andthe closing element is further configured such that continued translation of the carriage in the first direction after the attached cap has been located in the open end of the first tube brings the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube.

8. The tube closing apparatus of any claim 7, wherein the locating element is positioned at a first height above the base, and the closing element is positioned at a second height above the base, where the second height is less than the first height.

9. The tube closing apparatus of any claim 7 or claim 8, wherein the locating element is a locating roller comprising an annular chamfered edge, wherein the locating roller is positioned such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the annular chamfered edge into contact with the attached cap, thereby locating the attached cap into the open end of the first tube.

10. The tube closing apparatus of any preceding claim, wherein the base comprises a plurality of receptacles for receiving a tube strip, wherein the tube strip comprises aplurality of tubes comprising the first tube, and wherein each tube of the plurality of tubes comprises a respective attached cap.

11. The tube closing apparatus of claim 10, wherein each of the plurality of receptacles is positioned in a row parallel to the translation axis.

12. The tube closing apparatus of any preceding claim, the base further comprising a lever configured to pivot about an axis perpendicular to the translation axis; the lever comprising a first end positioned underneath the at least one receptacle, and a second end;wherein the lever is configured such that, when the first tube is positioned in the open configuration in the at least one receptacle, pressure applied to the second end causes the lever to pivot about the axis and push on an underside of the first tube.

13. The tube closing apparatus of claim 12, wherein the second end is positioned such that translation of the carriage in a second direction along the translation axis brings the carriage in contact with the second end, thereby applying pressure to the second end.

14. The tube closing apparatus of any of claims 10 to 13, wherein the plurality of receptacles comprises a first receptacle for receiving the first tube, and wherein the first receptacle comprises an inner surface which, in use, contacts the first tube; wherein the inner surface of the first receptacle comprises constraining structure configured to constrain the first tube within the first receptacle.

15. The tube closing apparatus of any of claims 10 to 14, wherein the tube strip comprises an end tube positioned at the opposite end of the tube strip to the first tube, wherein the plurality of receptacles comprises an end receptacle for receiving the end tube, and wherein the end receptacle comprises an inner surface which, in use, contacts the end tube; wherein the inner surface of the end receptacle comprises loosening structure configured to loosen the end tube within the end receptacle.

16. A tube closing apparatus for closing one or more tubes with caps attached thereto, comprising:a base comprising at least one receptacle for receiving at least a first tube of the one or more tubes;a carriage comprising a firstand a second closing means, wherein the carriage is configured to slide along a translation axis with respect to the base; andwherein the first closing means extends at an oblique angle with respect to the translation axis such that, when the first tube is positioned in an open configuration in the at least one receptacle, translation of the carriage in a first direction along the translation axis brings the first closing means into contact with the attached cap to bring the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube relative to the open configuration; andwherein the second closing element is positioned and configured such that continued translation of the carriage in the first direction after the attached cap has been brought into the first configuration brings the second closing means into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube.

17. A tube closing apparatus for closing one or more tubes with caps attached thereto, comprising:a moveable element comprising at least one receptacle for receiving the one or more tubes, the one or more tubes comprising a first tube; anda head element comprising an angled surface and a closing element, wherein the moveable element is configured to move the at least one receptacle along a translation axis with respect to the head element;wherein the angled surface extends at an oblique angle with respect to the translation axis such that, when the first tube is positioned, in an open configuration, in the at least one receptacle, movement of the moveable element in a first direction along the translation axis brings the angled surface into contact with the attached cap to bring the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube relative to the open configuration; andwherein the closing element is configured such that continued translation of the moveable element in the first direction after the attached cap has been brought into the first configuration brings the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube.

18. The tube closing apparatus of claim 17, wherein the moveable element comprises a conveyor belt, wherein the at least one receptacle is a plurality of receptacles, and each receptacle of the plurality of receptacles is positioned along the translation axis.

19. A system comprising the tube closing apparatus of any preceding claim, and a first tube comprising an attached cap.

20. A method of closing one or more tubes with caps attached thereto using a tube closing apparatus, the tube closing apparatus comprising a base and a carriage, the method comprising:positioning a first tube comprising an attached cap in a receptacle of a base;sliding the carriage along a translation axis with respect to the base, wherein the carriage comprises an angled surface and a closing element, the angled surface extending at an oblique angle with respect to the translation axis;continuing to translate the carriage in the first direction to bring the angled surface into contact with the attached cap, thereby bringing the attached cap into a first configuration in which the attached cap is closer to an open end of the first tube; andcontinuing to translate the carriage in the first direction after the attached cap has been brought into the first configuration, to bring the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube.

21. The method of claim 20, wherein the angled surface is a first angled surface and the oblique angle is a first oblique angle, wherein the carriage further comprises a second angled surface positioned in between the first angled surface and the closing element, and the second angled surface extends at a second oblique angle with respect to the translation axis; the method further comprising:continuing to translate the carriage in the first direction after the attached cap has been brought into the first configuration to bring the second angled surface into contact with the attached cap, thereby bringing the attached cap from the first configuration to a second configuration, wherein the attached cap is closer to the open end of the first tube when in the second configuration compared to the first configuration; andcontinuing to translate the carriage in the first direction after the attached cap has been brought into the second configuration, to bring the closing element into contact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube.

22. The method of claim 20 or claim 21, wherein the carriage further comprises a locating element, the method further comprising:continuing to translate the carriage in the first direction after the attached cap has been brought into the first configuration to bring the locating element into contact with the attached cap, thereby locating the attached cap into the open end of the first tube; andcontinuing to translate the carriage in the first direction after the attached cap5 has been located in the open end of the first tube to bring the closing element intocontact with the attached cap, thereby pressing the attached cap into the open end of the first tube to close the first tube.

24. A computer readable medium having data stored thereon representative of the tube10 closing apparatus of any of claims 1 to 18, the data being such that it can be relayed toan additive manufacturing device to enable the additive manufacturing device to fabricate the tube closing apparatus based on the data.

Images