Patent Application
20240100721
This application claims the benefit of European Patent Application No. EP22197861.2 filed Sep. 26, 2022, this application also claims the benefit of European Patent Application No. EP22197863.8 filed Sep. 26, 2022, and this application also claims the benefit of Swiss Patent Application No. CH000128/2023 filed Feb. 13, 2023, the disclosures of each of the foregoing are hereby incorporated by reference as if fully rested herein.
The present disclosure relates generally to a gripping appliance, and systems and methods utilizing said gripping appliance, and in more specific aspects to the subject matter set forth in the claims.
Numerous fields of technology require the conveyance of samples to and from measurement appliances. A non-limiting example is in thermal analysis systems for material characterization, wherein crucibles containing a sample need to be placed, for non-limiting instances, in a furnace of a differential scanning calorimeter or a thermogravimetric analysis instrument, and be removed from the furnace once the measurement is completed. The placing tolerance shall be low, for instance less than 0.2 mm from an aim point, so as to achieve highest accuracy of the measurement and/or analysis performed. JP 2010-203843 discloses a device suitable to replace and measure automatically and successively a plurality of samples in a simultaneous measuring device for an X-ray and thermal analysis using a partition, a furnace body cover or the like. To this extent, JP 2010-203843 suggests a conveyance device having gripping members which are pivotably suspended by axes. A centrally arranged plunger serves to actuate the grippers, whereas the lower ends of the grippers are urged to pivot towards each other by a spring. However, given the high cycle number such a gripping appliance will usually be subjected to, wear for instance of the axes and the corresponding running surfaces of the grippers might become an issue. Also, ease of replacement of components is relevant in order to reduce downtime and cost upon maintenance.
It is an object of the present disclosure to provide a gripping appliance of the type initially mentioned. In one aspect, the herein suggested gripping appliance shall overcome certain issues of the art. The gripping appliance shall in aspects be suitable for the conveyance of samples to and from, for non-limiting instances, a furnace of a differential scanning calorimeter or a thermogravimetric analysis instrument. In further aspects, the herein disclosed gripping appliance shall be easy and fast to maintain and to repair, and contain a minimum of parts which are subject to wear or are otherwise prone to fail. In still a further aspect, it is desirable that any components which are subject to wear or are otherwise prone to fail are easy to replace. Further, it might prove advantageous if in particular those components which are subject to wear or are otherwise prone to fail are low cost components. In further aspects, the gripping appliance shall enable a high placement accuracy of a sample and/or shall have a low space requirement in a plane where the sample is located.
This is achieved by the subject matter described in claim 1.
Further effects and advantages of the disclosed subject matter, whether explicitly mentioned or not, will become apparent in view of the disclosure provided below.
Accordingly, disclosed is a gripping appliance comprising a base member and a head assembly releasably attached to the base member and extending distal from the base member. The gripping appliance further comprises a plunger actuator and a plunger. The plunger actuator is arranged and configured to move the plunger along a proximal-distal axis of the gripping appliance. The plunger actuator and the plunger may in embodiments form part of or be attached to the base member. The term “distal” may denote a direction towards an end of the appliance where the appliance is intended to be brought into contact with and manipulate an object, while “proximal” denotes the opposite direction. The spatial orientation of the proximal-distal axis may in aspects be defined by the axis along which the plunger may move. A longitudinal axis of the plunger may in embodiments define the proximal-distal axis. The head assembly comprises a carrier and a number of at least two gripping legs, which may in particular embodiments be equidistantly arranged along the circumference of the carrier. A number of three, four, or more gripping legs may prove advantageous, as three or more gripping legs, in particular if equidistantly arranged along the circumference of the carrier of the head assembly, result in an intrinsic centering function on a gripped object, and at the same time avoid that a gripped object laterally slips out between the gripping legs. It is understood, however, that if the gripping legs are provided with appropriately contoured gripping tips, the risk of a gripped object slipping out between the gripping legs can be largely reduced, if not avoided. The carrier further has a through opening extending along the proximal-distal axis and configured and arranged to receive the plunger therethrough. In aspects, it may be said that a longitudinal extent or axis of the through opening defines the proximal-distal axis of the gripping appliance. A cross-sectional shape and dimension of said through opening may correspond to a cross-sectional shape and dimension of the plunger such that the through opening of the carrier allows the plunger to be received therein and move inside the through opening along the proximal-distal axis of the head assembly, or the gripping appliance, respectively, at least within a minimum required range of motion. The through opening may in embodiments guide the plunger during said movement. It is implicitly defined by said arrangement that, if the plunger extends distally from the carrier, the distal part of the plunger is located inside a space between the gripping legs. The gripping legs each comprise a fixation portion, a tip portion distal of the fixation portion, an actuation portion adjacent to and proximal of the tip portion, and a flex portion defined between the actuation portion and the fixation portion. The actuation portions of the gripping legs are configured to be in contact with the plunger at least when the plunger is in an extended, distal position. The fixation portions of the gripping legs are rigidly, that is, non-articulated, mounted to the carrier of the head assembly. At least the actuation portions and the tip portions of the gripping legs are arranged distal from the carrier of the head assembly and the gripping legs are arranged such that, when no force is transferred from the plunger to the gripping legs, the tip portions of the gripping legs converge in a proximal-distal direction. i.e., towards a distal end, of the gripping appliance.
The actuation portions of the gripping legs may be configured to be in contact with the plunger in that the gripping legs are shaped and arranged on the carrier such that a clearance of a passage surrounded by the actuation portions, when no force is transferred from the plunger to the gripping legs, is smaller than a cross sectional dimension of a part of the plunger which is intended to be moved at an axial, or proximal-distal, position of the actuation portions.
Preferably, the range of motion of the plunger is chosen such that it can be retracted, i.e., displaced proximally, sufficiently far that it does not transfer a force onto the actuation portions of the gripping legs. In further embodiments, the range of motion and the shape of the plunger is chosen such that it can be retracted, i.e., displaced proximally, sufficiently far that a part of the plunger comes into contact with the actuation portions of the gripping legs and displaces the actuation portions of the gripping legs by a first amount.
The plunger can be extended, i.e., displaced distally, so that a part of the plunger comes into contact with the actuation portions of the gripping legs and displaces the actuation portions of the gripping legs by a second amount. The displacement of the actuation portions in the radially outward direction causes a displacement of the tip portions of the gripping legs, radially outward, whereby the distal gripping end of the gripping appliance opens. At the same time, the flex portions of the gripping legs are flexed, which yields a radially inward directed restoring force to be exerted on the actuation portions and the tip portions.
It is noted that within the framework of the present disclosure the use of the indefinite article “a” or “an” does in no way stipulate a singularity nor does it exclude the presence of a multitude of the named member or feature. It is thus to be read in the sense of “at least one” or “one or a multitude of”.
As indicated above, the plunger comprises a contact portion intended for contact with the actuation portions of the gripping legs. In particular, the contact portion may comprise a tapered portion which is tapered towards a distal end of the plunger. At least a proximal or aft end of the contact portion has a cross-sectional dimension which is larger than a clearance of a passage surrounded by the actuation portions of the gripping legs when no force is transferred from the plunger to the gripping legs. The plunger may in particular have a circular cross section, in which case the cross-sectional dimension is a diameter. In further embodiments, the plunger may have a cross section of a regular polygon whereby the number of sides of the polygon equals the number of gripping legs, in which case the cross-sectional dimension is an inscribed circle diameter. It may be found advantageous if the tapered portion extends further distally to a cross sectional dimension or diameter which is smaller than the clearance of the passage surrounded by the actuation portions of the gripping legs when no force is transferred from the plunger to the gripping legs. This ensures that the contact portion of the plunger smoothly runs into contact with the actuation portions of the gripping legs. Proximal from the tapered portion the contact portion of the plunger, i.e., at least a part of the plunger proximally adjacent the tapered portion of the contact portion, may have a constant cross section, or, in more particular embodiments, be cylindrically shaped, along the proximal-distal extent of the plunger. This enables the contact portion to be smoothly introduced between the contact portions of the gripping legs with the undersized distal part of the tapered portion ahead, while gradually spreading the actuation portions and hence the tip portions of the of the gripping legs when further travelling distally. Once a proximal end of the tapered portion has been reached, the constant cross-section portion of the contact portion comes into contact with the actuation portions of the of the gripping legs, thus maintaining a constant opening of the gripping legs when the plunger is further advanced distally. For the sake of completeness, it shall be noted that the cross section of said constant cross-section portion of the contact portion is at least essentially the same as that of the proximal end of the tapered portion. The outer surface of the plunger, at least in the contact portion, is continuous, without steps which might hinder smooth sliding of the contact portion of the plunger and the actuation portions of the gripping legs relative to each other.
A distal end of the plunger may be pointed and form a distally pointing spike. Said spike may be used to pierce, for instance, a lid of a crucible by advancing the plunger distally. In providing the contact portion of the plunger with a proximal portion of constant cross-section along a proximal-distal, or axial, extent, the plunger may be advanced distally to pierce a lid without effecting a further actuation of the gripping legs.
In further non-limiting embodiments, the tip portions of the gripping legs in a very distal tip portion, adjacent and forming a distal end or tip of the gripping legs, are angled away from the center of the gripping appliance relative to the more proximal portions of the tip portions, so as to at least converge to a lesser degree in the proximal-distal direction than the more proximal portions of the gripping legs when no force is transferred from the plunger to the gripping legs. Said geometry of the very distal tip regions of the tip portions yield a smoother contact of these very distal tip portions with an object to be gripped. Ideally, the very distal tip regions extent at least essentially in the proximal-distal direction and not or only insignificantly in a radial inward or outward direction when gripping an object. It might thus be, as outlined in more detail below, that the gripping legs are specifically chosen for a particular object to be gripped.
The fact that the head assembly is releasable attached to the base member facilitates said task. Rather than replacing each gripping leg individually at the gripping appliance, the entire head assembly can be changed to a head assembly bearing gripping legs of different geometry and/or stiffness of the flex section. The gripping fingers comprise no movable parts, bearings and so forth, which avoids wear of such elements. Rather, the gripping legs are rigidly attached to the carrier of the head assembly, and the gripping movement is enabled by the flex portions of the gripping fingers, which provides superior lifetime when compared to gripping legs which comprise or are attached to the head assembly or the base member via hinges. Once the flex portions should degrade due to continuous oscillation, the entire head assembly may be replaced and the gripping legs themselves may be replaced offline, which reduces downtime and facilitates maintenance.
The above-described gripping appliance can be provided with slender tip portions of the gripping legs. The drive of the gripping legs is provided comparatively far proximal and radially inward from the gripping legs. As a result, the distal tip portion of the gripping appliance can be built with a low space requirement, which in turn enables the use of the gripping appliance in connection with a multitude of quite narrowly placed samples. In other words, in connection with the herein described gripping appliance a narrow arrangement of samples is enabled, which in turn means a larger number of samples can be provided in a given space or on a given surface. Moreover, the herein described gripping appliance may be used in restricted space environments.
In another aspect, disclosed is a head assembly for a gripping appliance as described above, wherein the carrier comprises a number of flat outer mounting surfaces rotational-symmetrically arranged around an outer circumference of the carrier. In particular, the number of flat outer mounting surfaces may equal the number of gripping legs. The fixation portions of the gripping legs comprise flat mounting surfaces abutting the flat outer mounting surfaces. In non-limiting embodiments, the gripping legs are mounted to the carrier by screws extending through the fixation portions of the gripping legs.
In still a further aspect, disclosed is a gripping leg for a gripping appliance and/or a head assembly as outlined above. The flex portion is configured with a minimum bending stiffness in response to a moment induced by a force acting perpendicular to a plane of the flex portion. The resistance against bending in other directions may be chosen considerable higher. The actuation portion comprises a base which extends between and merges into the tip portion and the flex portion. The actuation portion further comprises a tongue which originates from the base. The tongue projects from the base. Preferably, a tongue angle is between 5° and 85°. The tongue angle is the angle between the plane of the flex portion and a connecting line between a point on the origin of the tongue and a point on the tip of the tongue. The tip of the tongue are the points with the greatest distance from the base.
The gripping leg may be mounted on the carrier of the head assembly such that the tongue extends radially inward. The tongue, or a tip of the tongue, respectively, in this case constitutes a counterpart abutment for the plunger.
In a preferred embodiment, the tongue angle is greater than the cone angle of the tapered portion of the plunger. Thereby, it is ensured that the tip of the tongue establishes the contact with the plunger, which results in a smooth and controlled motion of the tip portions.
In a preferred embodiment, the distance between the tip of the tongue and the base is greater than half of the difference between the cross-sectional dimension of the plunger at the proximal and the distal end of its tapered portion. Thereby, it is prevented that the base or the flex portion of the gripping legs contact the plunger. Consequently, the control of the motion of the tip portions is improved.
In non-limiting embodiments, the flex portion is trapezoidally shaped and widening from the actuation portion towards the fixation portion. More particularly, the flex portion may be shaped as a frame comprising two flex legs extending along the sides of the flex portion between the actuation portion and the fixation portion. The trapezoidal shape of the flex portion may yield effects on the kinematics of the tip portion, such as to yield a straight leg travel.
The tongue of the actuation portion may be slanted towards the tip portion, thus avoiding mutual locking of the tongue and the plunger when the plunger travels into the distal direction and is in contact with the tongue. The tongue may have the shape of a trapezoid with a straight baseline whereby the side opposite of the straight baseline is formed as rounded concave arch, thus having a tip line for contact with a plunger of circular cross-section. In further embodiments, the tongue may have the shape of a rounded convex arch, extending between the end points of the straight baseline.
A window may be formed in the base of the actuation portion, having a size and shape at least essentially conformant with or greater than the size and shape of the tongue. Said window has a straight baseline, wherein the straight baseline of the tongue joins the straight baseline of the window and the tongue extends from the straight baseline of the window. The straight baseline of the window in more particular embodiments forms the proximal boundary of the window. The actuation portion may be manufactured by cutting the shape of the tongue, with the exception of the straight baseline, into the base of the actuation portion, for instance by laser cutting, and subsequently bending the tongue away from the base of the actuation portion into the desired direction and about a desired amount, thereby forming the window in the base. The transition between the base and the tongue is provided in the straight baseline.
The gripping leg may be a seamless one-piece member. However, it may be assembled from individual segments. For instance, the tongue may be joined to the base, and may for more particular, non-limiting instances be glued, welded, soldered, screwed or riveted. The gripping leg can be made of sheet metal. In some embodiments, the tongue may be realized by a wedged part of a material. The material of the tongue and the base may differ, for example to choose a material with desirable gliding properties for tongue while choosing a material with desirable flexing properties for the flex portion of the gripping leg.
Further disclosed is a conveyance system configured and adapted to convey objects, for instance crucibles, between at least two locations. The conveyance system comprises a gripping appliance as set forth above and at least one drive configured to move the gripping appliance along the proximal-distal axis of the gripping appliance and perpendicular to the proximal-distal axis of the gripping appliance.
As outlined above, in the herein described gripping appliance yields, in particular at its distal tip where samples are manipulated, very low space requirements. To this extent, disclosed is a sample manipulation system which comprises at least one of a gripping appliance and/or head assembly as set forth above, and further a tray. The tray has a top side comprising a multitude of receiving indentations which are intended, configured and adapted for receiving a sample. The receiving indentations may be configured for use with samples or crucibles of a specific shape and size. It may be provided that the receiving indentations are at least essentially circular in cross section, and the distance between the outer rim of a receiving indentation and the outer rim of a closest neighboring receiving indentation is 20% of the diameter of a receiving indentation or less. The samples and/or crucibles may thus be densely packed on the tray. In further, more specific embodiments elongated indentations may in addition be provided which extend radially from and merge into the receiving indentations. The number of elongated indentations extending radially from and merging into each of the receiving indentations is at least equal to the number of gripping legs of the gripping appliance and/or the head assembly, and at least some of the elongated indentations merging into each of the receiving indentations are circumferentially distributed in a circumferential pattern conformant to a circumferential pattern formed by the gripping legs around the gripping appliance and/or the head assembly. The tray according to the invention has a top side comprising a multitude of receiving indentations. Every one of the receiving indentations is intended, configured and/or adapted for receiving a sample. The receiving indentations may be configured for use with samples, such as crucibles, of a specific shape and size. The tray according to this embodiment comprises further a coding.
The coding is preferably an electronic coding. Most preferably the electronic coding is a memory or a chip which can be read out via the same conductor with which it is powered. Such chips are for example known as 1-Wire Chips. Such an electronic coding has the advantage that it offers great flexibility in the length and structure of the coding while still allowing the tray to be stored without a power source on its own. In alternative embodiments of an electronic coding, a memory or a chip providing the coded information returns the information via a conductor different from the ones with which it is powered. In some embodiments, the tray may comprise a power source for the coding such as a rechargeable battery. An electronic coding is flexible and robust as soiled contacts can easily be cleaned, if needed while the memory or the chip itself can be embedded in the tray and thereby protected from the surrounding.
In further embodiments, the coding is a mechanical coding. Most preferably, the mechanical coding is a pattern machined in a side wall or in the lower side of the tray which is suitable to be read out by a set of contact sensors or by the way it scatters or blocks a light signal. In further embodiments, the coding is a RFID chip.
In still further embodiments, the coding is a 2D-coding pattern such as for example a bar code or a QR code. In addition or instead, the coding can be a human readable number and/or letter combination, applied onto the tray.
Preferably, the electronic, mechanical, RFID chip coding and/or the 2D-coding pattern is arranged on one of the side walls or the lower side, opposite of the top side, of the tray. Most preferably, the human readable code and/or the 2D-coding pattern is arranged on the top side of the tray. Preferably, the tray comprises a human readable code on its top side in addition to an electronic, mechanical, RFID chip coding and/or a 2D-coding pattern which is arranged on one of the side walls or the lower side, opposite of the top side, of the tray.
Preferably, the coding comprises information about a class of trays to which a given tray belongs and/or a unique identification. Preferably, the coding comprises information about a class of trays to which a given tray belongs in addition to an identification which makes it unique. The trays of a given class of trays can for example comprise receiving indentations which are intended, configured and adapted for receiving a sample of the same specific shape and size. In further embodiments, trays of a given class of trays comprise a different number of receiving indentations than trays of other classes. In further embodiments, trays of a given class of trays comprise a different arrangement of receiving indentations than trays of other classes.
Preferably a user can create user specific coding for the trays used by himself, most preferably with a computer program. The user specific coding can be written into the electronic coding, associated to signal of the RFID chip and/or printed on a label comprising the respective 2D-coding pattern and/or the human readable code to allow the user to adapt the trays to an existing sample or object management system. Most preferably, the user specific coding comprises only the unique identification, while the information about the class of trays is predefined by the manufacturer of the trays. This prevents conflicts which could occur, if the user sets by accident a unique identification which is later chosen by the manufacturer to represent a class of trays.
The use of a coding attached to the tray has the advantage that the tray can be identified—either automatically or with the help of the user—by a sample manipulation system and/or a conveyance system. This allows to adapt the motion of the gripper to the tray and to the samples for which the receiving indentations are intended and adapted for. In a preferred embodiment, for example, the gripper is instructed to open to a greater extend if the tray is identified as a tray of a class adapted to samples with a greater diameter than in a case where the tray is identified as a tray of a class adapted to samples with a smaller diameter. Similarly, the motion of the gripper can be adapted to a comply with the arrangement of the receiving indentations on trays of the identified class of trays. The gripper is preferably a gripping appliance according to the invention. The motion of the gripper and the extend of its opening are preferably controlled by a control which acts on the respective drives for the different motions.
By including a unique coding to each tray, the user can identify a given sample by its location on a tray together with its unique coding. The control of the gripper can use this information to specifically handle the sample in question by identifying the tray using its unique coding and moving the gripper to the given location of the sample on the tray in question. This facilitates the preparation of the samples. Further, the unique coding of the tray can allow the user to instruct the gripper to handle samples from the specified tray differently than samples from other trays. For example, the acceleration of the gripper while gripping a sample can be reduced, if a given sample is particular sensitive to accelerations.
Arranging a human readable code and/or a 2D-coding pattern on the top side of the tray facilitates the user to access the coding of the tray, even if it is already loaded with samples. Thereby, the user can assign tray specific instructions to the control of the gripper even after the samples are arranged on the tray. A 2D-coding pattern can be scanned with a suitable scanner, e.g., a barcode or QR scanner, and thereby automatically entered in an interface to the control to allow the user to specify instructions related to the tray and/or to samples arranged on it. Also, a human readable code can be detected automatically, for example by a camera. Further, a user can input the human readable code of the tray in question into the interface of the control by e.g., typing it in or reading it out loud. The interface to the control can be a part of the control itself or it can be an assistant program, running on a computer or on a mobile device for example, which is equipped to transmit the data to the control in a suitable format.
Preferably the tray is blue. The samples analysed with a thermal analysis system are typically crucibles which are golden, metallic grey and/or white. Therefore, there is a significant colour contrast to a blue tray which facilitates the recognition of samples on the tray and the identification of empty receiving indentations. For such a recognition, the thermal analysis systems are preferably equipped with a camera. The camera can be arranged on the gripper, in a lid covering the trays arranged in the tray holder in times where no access to them is needed or in another place of the system from where the sample tray in the tray holder is visible. The visible recognition of samples on the tray allows to detect which receiving indentations are occupied and which ones are empty. This information can be used by the control of the gripper, e.g., to avoid trying to grasp a sample at an empty receiving indentation. The information can also be transmitted to the user in order to allow him to check on the status of the samples and the tray and/or to estimate the time until new samples are needed. In other embodiments, empty receiving indentations can be detected by the gripper itself due to the amount by which it can close without significant resistance.
In one embodiment, of the tray the receiving indentations are at least essentially circular in cross section. Elongated indentations extend radially from the receiving indentations. In this embodiment, the trays are particularly well equipped to be used with the gripping appliance according to the invention, as the elongated indentations give the gripping legs more freedom to move. Without such elongated indentations, only samples which extend above the top side of the tray can be grasped by the gripping appliance according to the invention. Elongated indentation of different shapes can be used with other types of grippers where legs might approach the samples on other paths. For example, spiral-like elongated indentations might be used for trays to be used with grippers with legs approaching the sample on spiral-like paths.
In one embodiment the distance between the outer rim of a receiving indentation and the outer rim of a closest neighboring receiving indentation is 20% of the diameter of a receiving indentation or less. The samples and/or crucibles may thus be densely packed on the tray.
In one embodiment, the length of the elongated indentations is greater than the distance between the outer rim of a receiving indentation and the outer rim of a closest neighboring receiving indentation. Thereby, the gripping legs have more space to open towards the sides of the sample than the distance between the samples. This allows the samples and/or crucibles to be densely packed on the tray. The length of the elongated indentations is preferably measured as the distance between the outer rim of an incircle of a receiving indentation and the outer rim of an incircle of a second receiving indentation which arranged in the direction in which the elongated indentation is elongated.
In one embodiment elongated indentations may be provided which extend radially from and merge into the receiving indentations. The number of elongated indentations extending radially from and merging into each of the receiving indentations is at least equal to the number of gripping legs of the gripping appliance and/or the head assembly, and at least some of the elongated indentations merging into each of the receiving indentations are circumferentially distributed in a circumferential pattern conformant to a circumferential pattern formed by the gripping legs around the gripping appliance and/or the head assembly.
Preferably, the gripper is part of a sample manipulation system. This sample manipulation system comprises a tray holder. The tray holder is adapted to hold a tray comprising a coding. Preferably, the tray holder comprises means to read out the coding of the tray.
Alternatively, means to read out the coding of the tray can be arranged outside of the tray holder and can comprise for example a camera arranged in a lid, on the gripper or on another part of the sample manipulation system or its surrounding form where a visible coding of the tray can be seen. Instead of a camera and a visible coding, an electronic coding can be read out in some distance by a reader comprising an antenna for receiving an electromagnetic signal emitted or reflected by the electronic coding which can e.g., be attached to the gripper, a lid or another part of the sample manipulation systems. Movable parts such as gripper and lid can also establish an electrical and/or mechanical contact to read out a coding.
Preferably, the sample manipulation system comprises further a control of the gripper. This control is suitable to control the gripper while considering the information stored in the coding of the tray. The advantages of such a control where already outline above.
Preferably, means to read out the coding of the tray are means to read out the electronic, mechanical, RFID chip coding and/or the 2D-coding pattern. Preferably, means to read out the coding of the tray are arranged on one of the side walls or the lower side of the tray holder such that they can read out the respective coding of the tray once the tray is inserted into the tray holder. This allows to position the coding and the means to read it out in a well-defined and small distance of each other. This allows to use means to read out which need a physical contact such as an electrical connection and optimizes the signal quality if means to read out comprise detectors to receive a signal such as an emitted or reflected radio signal or a scattered or reflected light signal. It further allows the means to read out to read out the code by detecting a mechanical contact or a proximity.
Most preferably, the tray comprises an electronic coding which comprises a memory or a chip which can be read out by the same conductors which provide power to the memory or chip in question and the tray holder comprises contact regions in which conductors to power and read out the memory or the chip comprising the coding of the tray are provided. Once the tray is arranged in the tray holder, the contact regions of the tray holder contact the contacts of the electronic coding of the tray and the information of the coding stored in the memory or the chip can be read out. Further, the receipt of the signal indicates the presence of the tray in the tray holder.
The sample manipulation system is preferably part of a thermal analysis systems for material characterization. The gripper is preferably a gripping appliance according to the invention.
Preferably, the tray holder is adapted to hold the tray in a predefined orientation. Most preferably, the tray holder comprises an indentation into which the tray fits.
In a preferred example the tray is, in the view on its top side, rectangular, whereby at least one of the sides of this rectangle comprises an indentation or a protrusion such that the symmetry of the rectangular shape is broken and a unique orientation is defined with respect to a tray holder with a correspondingly shaped protrusion or indentation.
Preferably, the control of the gripper is the control of the gripping appliances and is part of the thermal analysis system for material characterization.
Preferably, the means to read out the coding of the tray transmit the read out data to the control of the gripper, where the control can use this information to adapt the motion of the gripping appliances depending on the information stored with the coding.
Preferably, the coding comprises information of a class of a tray. Preferably, a database is accessible by the control or stored in the control which associates information specific for a class of trays with the coding indicating this class. The information can be, for example, the size and diameter of samples which fit in the receiving indentations of the trays of this class and/or the arrangement of the receiving indentations on trays of this class.
Preferably, a tray comprises a piercing position. Preferably, the piercing position is an elevation on the top side of the tray. This elevation is essentially circular in cross section. The height of the elevation with respect to its surrounding is such that tip portions of the gripping legs do not collide with the tray during the piercing action of a sample arranged on the piercing position. Proving such piercing position on a tray has the advantage that it facilitates the control of the piercing process and that it can be replaced and cleaned easily if needed.
In still further aspects, disclosed is a method of conveying an object between at least two locations. The method comprises:
Subsequently, the object may be placed at the place of destination and the plunger may be advanced into the distal direction, whereby the plunger contacts the actuation portions of the gripping legs and forces the tip portions of the gripping legs radially apart, thereby releasing the object. After the object has been released, the gripping appliance may be moved in the proximal direction so as to get clear of the object.
As suggested above, the gripping legs may be chosen so as to fit a specific object. In this respect, the method may further comprise selecting a head assembly out of a multitude of head assemblies, wherein the head assembly is selected such that the flex portions of the gripping legs induce a defined radially inward acting force at the tip portions when the plunger is retracted and the tip portions abut the object. In aspects, the head assembly may be chosen such that a frictional force induced by the radially inward acting force and effective between the tip portions of the gripping legs and the object is greater than the weight force of the object.
As further suggested above, the plunger may comprise a pointed distal tip. The object may be a crucible comprising a sample and the method may comprise moving the plunger distally to pierce and perforate a lid closing the crucible with the pointed distal tip of the plunger.
It is understood that the features and embodiments disclosed above may be combined with each other. It will further be appreciated that further embodiments are conceivable within the scope of the present disclosure and the claimed subject matter which are obvious and apparent to the skilled person by virtue of the present disclosure.
The subject matter of the present disclosure is now to be explained in more detail by means of selected exemplary embodiments shown in the accompanying drawings. The figures show:
It is understood that the drawings are highly schematic, and details not required for instruction purposes may have been omitted for the ease of understanding and depiction. It is further understood that the drawings show only selected, illustrative embodiments, and embodiments not shown may still be well within the scope of the herein disclosed and/or claimed subject matter.
The gripping appliance outlined in connection with
An exemplary process of gripping an object is outlined in connection with
In the example shown in
In the embodiment according to
In the embodiment according to
Window 206 and tongue 205 can have a generally conformant size and shape or the window 206 can be greater than the tongue 205. This is due to the fact that tongue 205 may be manufactured in performing a suitable cut, for instance by laser cutting, into the base of actuation portion 203 and subsequently bending tongue 205 out of the plane of the sheet forming the base of actuation portion 203. In other embodiments, however, tongue 205 may be a separate member attached to the base of actuation portion 203. Any suitable attachment method may be applied, including, while not limited to, gluing, soldering, welding, screwing and riveting. It is understood that, if tongue 205 is an individual member attached the base of actuation portion 203, the base of actuation portion 203 may not comprise window 206.
Actuation portion 203 distally merges into tip portion 204, which is distally adjacent to actuation portion 203. Tip portion 204, in a very distal portion 207, is angled with respect to a more proximal portion of the tip portion. The very distal portion 207 is angled in a direction opposite to that of tongue 205. As will be appreciated, when gripping leg 24 is properly mounted to a head or a gripping appliance as outlined above, tongue 205 projects radially inward from the base of actuation portion 203. Accordingly, very distal portions 207 of the tip portions 204 of the gripping legs mounted to the head or gripping appliance are less convergent in the distal direction when compared to the more proximal portions of the tip portions 204, or might even diverge distally, dependent upon the specific geometry of a gripping leg and the position of the plunger, i.e., dependent upon whether the gripping appliance is opened or closed at its distal end. Said angulation of the very distal tip portion 207 might serve to better accommodate an object to be gripped. Gripping leg 24 may generally be manufactured from a piece of sheet metal, in particular from a sheet of spring steel.
Trays 40a, b, are shown in more detail in
On both trays, elongated indentations 42 extend radially from the receiving indentations 41 and connect them with each other.
As shown in
In both,
Trays 40 for the use with other grippers may be equipped with elongated indentations 42 of a difference shape to allow the gripping means of these grippers the needed freedom to move. If the depth of the receiving indentation 41 is smaller than the height of the objects 100, elongated indentations 42 can also be omitted if the gripper can grasp the objects 100.
Both trays 40 shown in
A further coding 50 is a mechanical coding 50m. The mechanical coding 50m is a pattern machined in one of the side walls 43s of the tray 40. The mechanical coding 50m is suitable to be read out by suitable detection means such as set of contact sensors, by a set of proximity sensors or by the way it scatters or blocks a light signal. Another coding 50 which is depicted is a RFID chip 50r.
In still further embodiments, the coding 50 is a 2D-coding pattern 50p such as for example a bar code or a QR code. In addition or instead, the coding 50 can be a human readable number and/or letter combination 50ht, 50hi, printed or otherwise applied onto the tray 40.
The electronic 50e, mechanical 50m and RFID chip 50r coding 50 are arranged on one of the side walls 43s of the tray 40. The human readable code 50ht, 50hi, and the 2D-coding pattern 50p are arranged on the top side 43t of the tray 40.
In the depicted embodiments, the coding 50 comprises information about a class of trays to which a given tray belongs in addition to a unique identification. This is visible in the case of the human readable number and letter combination 50ht, 50hi: The letter 50ht indicates in this example the class of the tray, which is “L” for “trays, suitable large samples” in the case of
The trays 40, depicted in
The tray holder 60, shown in
The tray holder 60 comprises means 55 to read out the coding 50 of the tray 40. The means to read out 55 are the read out electronic 55e of the electronic coding 50e, a sensor 55m to read out the mechanical coding 50m, and an RFID chip reader 55r. These means are arranged on the side wall 63s of the tray holder 60 and arranged at such locations, that they can read out the respective coding 50 of the tray 40 once the tray 40 is inserted into the tray holder 60.
Once the tray 40 arranged in the tray holder 60, the contact regions 56a, 56b of the tray holder 60 contact the contacts 51a, b of the electronic coding 50e of the tray 40 and the information of the coding 50 stored in the chip 51 can be read out and is transmitted via the line 70 to be processed or displayed.
The gripping appliances 1 is part of a sample manipulation system. The sample manipulation system is part of a thermal analysis systems for material characterization.
At some horizontal distance from the access channel 72, a tray 40 is arranged in a tray holder 60 which is part of the work area 71. The tray 40 comprises receiving indentations 41 formed to hold a plurality of objects 100 that may specifically be crucibles for receiving specimens of materials to be analyzed. Such trays 40 may for instance be formed so as to have the objects 100 or crucibles arranged therein, for example in an array of lines and columns. A crucible is an example of an object 100.
The tray 40 is arranged in a tray holder 60. Further, the tray 40 is in the shown embodiment equipped with an electronic coding which comprises a chip 51. The tray holder 60 comprises contacts to power and read out the chip 51 via the contacts 51a, b on the tray 40. The contacts to power and read out the chip 51 which are comprised in the tray holder 60 are connected to a line 70 which feeds the information contained in the coding to a control 80.
The sample manipulation system shown in
A conveyance system 90 comprises a drive 91 and a gripper, which is in the shown embodiment a gripping appliance 1. The drive 91 is configured to move the gripping appliance 1 along the proximal-distal axis 2 of the gripping appliance 1 and perpendicular to it. The gripping appliance 1 and was described in more detail in
In the depicted embodiment a camera 92, in this example a digital camera, is attached to the gripping appliance 1. A light source 92a to illuminate the camera's field of view is attached to the camera 92. Preferably, the light source 92a is in the form of a ring light surrounding the camera 92. The light source 92a preferably emits polarized light and the camera 92 includes a polarization filter so as to attenuate undesired reflections into the camera 92. The light source 92a for example emits white light in the visible spectrum.
The drive 91 moves the gripping appliance 1 together with the camera 92 and the light source 92a to various positions above work area 71 in both the horizontal directions (X-, Y-axis) and the vertical direction (Z-axis). These positions specifically include those which are appropriate for the gripping appliance 1 to receive or release objects 100 at any one of the receiving sample support 73 or the receiving indentations 41 of the tray 40, to capture images or at least partial images of any one of the receiving sample support 73, and/or an object 100, and/or the tray 40.
The thermoanalytical instrument 33 comprises further evaluation means 34: The evaluation means 34 identify an object 100 or the positions and presence of objects 100 on a tray 40 in the tray holder 60 using one or more images captured by the camera 12. The information from the evaluation means 34 is in the shown embodiment also provided to the control 80.
The information contained in the coding 50 which are transmitted to the control 80 by the line 70, allow to adapt the motion of the gripping appliance 1 to the class to which the tray 40 belongs and thereby to the objects 100 for which the receiving indentations 41 are intended and adapted for. In the depicted example, a class “L” of trays is adapted to objects with a greater diameter than trays of class “S”. If the control 80 receives an information by the line 70 that the tray 40 in the tray holder 60 is of class “L” the gripping appliance 1 is instructed by the control 80 to open to a greater extend compared to the case that control 80 receives an information by the line 70 that the tray 40 in the tray holder 60 is of class “S”.
In the depicted example, the information contained in the coding 50 which are transmitted to the control 80 by the line 70 includes further a unique identifier. This identifier is unique in the set of trays 40 which may be used in the thermoanalytical instrument 33 at hand. In this example, the user can identify an object by specifying its location of the tray and the unique coding of the tray. The user can, for example, specify that a sample of interest is arrange in the 3rd receiving indentations 41 in the 2nd row of the tray 40 with a given identifier. Further the user can specify that this object 100 should be moved with a smaller acceleration or that is should be the first one on the tray 40 to be measured. The control 80 of the gripping appliance and uses this information to specifically handle the defined sample as requested.
The tray 40 in the depicted embodiment is of blue color. The samples analyzed with a thermal analysis system are typically crucibles which are golden, metallic grey and/or white. Therefore, there is a significant color contrast to the blue tray 40. This facilitates the recognition of samples on the tray and the identification of empty receiving indentations which is done by the evaluation means 34.
While the subject matter of the disclosure has been explained by means of exemplary embodiments, it is understood that these are in no way intended to limit the scope of the claimed invention. It will be appreciated that the claims cover embodiments not explicitly shown or disclosed herein, and embodiments deviating from those disclosed in the exemplary modes of carrying out the teaching of the present disclosure will still be covered by the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 22197861.2 | Sep 2022 | EP | regional |
| 22197863.8 | Sep 2022 | EP | regional |
| CH000128/2023 | Feb 2023 | CH | national |
