Residual Sealing Force (RSF) test system and test head

Abstract

The test head 136 of the residual seal force (RSF) testing system 100 is described. The test head includes a housing 202, an anvil 204, and a ball roller assembly 208. The housing defines a first cavity 222, and the anvil is positioned at least partially within the first cavity. The ball roller assembly is configured to provide a contact point between the housing and the anvil during RSF testing. The test head may further include a retaining ring 203 configured to maintain the anvil at least partially within the first cavity.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit and priority of U.S. Provisional Patent Application No. 63 / 140,046, filed on January 21, 2021, and U.S. Patent Application No. 17 / 578,729, filed on January 19, 2022, both entitled "System, Method, And Apparatus For Automating Specimen Testing", the contents of which are hereby incorporated by reference in their entirety to form a part of this specification.

[0002] The present disclosure relates to specimen testing, and more particularly, to systems, methods, and apparatuses for automating residual seal force testing and / or compression friction measurement testing.

Background Art

[0003] Since the early 20th century, containers (e.g., bottles, vials, etc.) with elastomeric stoppers and in some cases crimp caps have continued to be the primary packaging system for parenteral (i.e., injectable) drugs. Parenteral products contained within such container packaging systems require a strong seal at the interface between the glass container and the elastomeric stopper to prevent contamination and product leakage. The seal is established during the manufacturing process but must withstand various handling, processing, and storage conditions prior to use.

[0004] In some examples, a container seal consists of three main components: a glass container, an elastomer stopper (e.g., a rubber stopper), and a cap, such as an aluminum cap, that secures the rubber stopper inside the container. When a metal cap is used, it is typically made of aluminum or an aluminum alloy and must be pressed onto the container to ensure a proper fit between the container and the elastomer stopper. In other examples, the cap is removed for other tests. Stopper variables affecting the container seal include dimensional properties and tolerances, along with the mechanical properties of the stopper components, including modulus of elasticity, hardness, and compressive strain.

[0005] Manufacturers of parenteral containers must employ quantitative methods to measure the force exerted by the stopper on the container after the initial seal is formed, until the end of the product's shelf life. For stoppers using metal caps, this force is measured using a residual seal force (RSF) test, while a compression friction (CF) test is used to evaluate glass containers sealed using plungers. The CF test is sometimes called a glide test. While existing RSF and CF testers can measure RSF and CF, such tests can be time-consuming, cumbersome, and labor-intensive. Therefore, it is desirable to provide more accurate, more robust, and / or automated systems, methods, and apparatus for RSF and / or CF testing. [Overview of the Initiative]

[0006] Systems, methods, and apparatus for testing are disclosed, substantially shown by at least one of the drawings and described in relation to at least one of the drawings. More specifically, systems, methods, and apparatus for determining residual sealing force and / or compression friction measurements of containers, in particular containers for parenteral pharmaceuticals, are disclosed.

[0007] The above-mentioned objectives, features, and advantages of the apparatus, systems, and methods described herein, as well as other objectives, features, and advantages, will become apparent from the following description of specific embodiments shown in the accompanying drawings, where similar or similar reference numerals refer to similar or similar structures. The drawings are not necessarily to scale and are primarily intended to illustrate the principles of the apparatus, systems, and methods described herein. [Brief explanation of the drawing]

[0008] [Figure 1a] This is a perspective view of an exemplary test system relating to an aspect of this disclosure. [Figure 1b] Figure 1a is a perspective view of the exemplary test system, with some parts removed to better illustrate the load strings. [Figure 2a] This is a plan cross-sectional view of a first exemplary test head according to an aspect of the present disclosure. [Figure 2b] This is a plan cross-sectional view of the first example test head in Figure 2a, which is in contact with the sample. [Figure 2c] This is a plan cross-sectional view of the first example test head in Figure 2a, which is in contact with the sample. [Figure 2d] This is a plan cross-sectional view of a first exemplary test head having a concave region at the contact point. [Figure 3a] This is a plan cross-sectional view of a second exemplary test head according to an aspect of the present disclosure. [Figure 3b] This is a plan cross-sectional view of the second example test head in Figure 3a, which is in contact with the sample. [Figure 3c] This is a plan cross-sectional view of the second example test head in Figure 3a, which is in contact with the sample. [Figure 4a] This is a perspective view of a third exemplary test head relating to an aspect of this disclosure. [Figure 4b] This is a plan cross-sectional view of the third example test head along section AA in Figure 4a. [Figure 5] This flowchart illustrates one example method for operating the example test system. [Modes for carrying out the invention]

[0009] For items referred to as singular, it should be understood that this includes cases where the item is plural, and vice versa, unless otherwise explicitly mentioned or made clear from the description. Grammatical connections are intended to represent any and all disjunctive and conjunctive combinations of combined phrases, sentences, and words, unless otherwise mentioned or made clear from the context. Enumerations of value ranges in this specification are not intended to be limiting, but refer individually to any and all values ​​that fall within that range, unless otherwise indicated herein, and each distinct value that falls within such a range is incorporated into the specification as if it were individually enumerated herein. In the following descriptions, terms such as “first,” “second,” “top,” “bottom,” “side,” “before,” and “after” are words of convenience and should not be interpreted as limiting terms. For example, in some examples, the first side is located adjacent to or near the second side, while the terms “first side” and “second side” do not implicitly indicate any particular order in which the sides are ordered.

[0010] Where used herein, terms such as “about,” “approximately,” and “substantially,” when accompanied by numerical values, are interpreted as indicating a deviation that a person skilled in the art would understand to be sufficient for the intended purpose. Ranges of values ​​and / or numerical values ​​are provided herein for illustrative purposes only and do not constitute a limitation on the scope of the embodiments described. The use of any and all examples or exemplary words provided herein (such as “e.g.,” “such as”) is intended merely to better highlight the embodiments and does not impose a limitation on the scope of the embodiments. The terms “e.g.,” and “for example”) are the beginning of a list of one or more non-limiting examples, specific examples, or embodiments. Words in the specification should not be interpreted as indicating any non-claimed elements essential to the implementation of the embodiments.

[0011] As used herein, the term "and / or" means any one or more items in the list linked by "and / or". For example, "x and / or y" means any element of the set of three elements {(x), (y), (x,y)}. In other words, "x and / or y" means "one or both of x and y". As another example, "x, y and / or z" means any element of the set of seven elements {(x), (y), (z), (x,y), (x,z), (y,z), (x,y,z)}. In other words, "x, y and / or z" means "one or more of x, y and z".

[0012] As used herein, “circuit” or “circuit section” includes any analog and / or digital components, power and / or control elements, such as a microprocessor, a digital signal processor (DSP), software, etc., separate and / or integrated components, or parts and / or combinations thereof.

[0013] As used herein, the terms “compression rod” and “compression pin” refer to rigid structures configured to apply compressive force to a specimen positioned within a test system, respectively. In the case of CF testing, for example, a compression pin can be used to compress an elastomer stopper into a rigidly supported parenteral container such as a vial.

[0014] As used herein, the terms “driven-coupled,” “driven-coupled to,” and “driven-coupled with,” respectively, mean a mechanical connection that enables a drive unit, device, apparatus, or component to transmit mechanical force to a driven unit, device, apparatus, or component.

[0015] As used herein, the term “processor” means a processing device, apparatus, program, circuit, component, system, and subsystem, whether implemented in hardware, in tangibly embodied software, or both, and whether programmable or not. The term “processor” as used herein includes, but is not limited to, one or more computing devices, wired circuits, devices and systems that modify signals, devices and machines that control systems, central processing units, programmable devices and systems, field-programmable gate arrays, application-specific integrated circuits, systems on a chip, systems comprising individual elements and / or circuits, state machines, virtual machines, data processors, processing equipment, and any combination thereof. A processor may, for example, be any type of general-purpose microprocessor or general-purpose microcontroller, a digital signal processing (DSP) processor, or an application-specific integrated circuit (ASIC). A processor may be coupled to or integrated into a memory device.

[0016] As used herein, the terms “memory” and / or “memory device” mean computer hardware or circuitry that stores information for use by a processor and / or other digital device. Memory and / or memory devices can be any suitable type of computer memory or any other type of electronic storage medium, such as read-only memory (ROM), random access memory (RAM), cache memory, compact disk read-only memory (CDROM), electro-optical memory, magneto-optical memory, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state storage, computer-readable media, etc.

[0017] A quantitative method for measuring the closing force exerted on a container after sealing can be performed using a constant rate compression testing machine. By applying slow constant rate compression to the sealed container, a stress vs. time curve can be created to determine the measured residual seal force (RSF) of a given closure seal in the sample. The RSF measurements can be determined for a variety of containers with various stopper sizes and shapes. The RSF measurements can be used, for example, to indicate the safety of the container stopper as part of the manufacturer's quality control. The initial force when the stopper compresses the container is a function of the vertical and horizontal crimping forces applied during the application (e.g., crimping) of an aluminum cap. However, due to the viscoelastic relaxation behavior of the rubber, the force of the stopper pressing against the container decays as a function of time, the elastomer composition, and the results of various processing procedures. In another example, a compression friction (CF) measurement test can be performed using a compression testing machine to confirm the suitability of a glass container sealed using an elastomer stopper (e.g., plunger). The CF measurement test may also be referred to as a sliding test.

[0018] To evaluate seal tightness, manufacturers may use a manual test system as part of their quality control process to measure the RSF or CF of parenteral packages generated during the container sealing process. Typically, manufacturers test small batches or small quantities (e.g., lot or line samples) as part of their quality control efforts. Since the RSF test and the CF test are considered destructive tests (i.e., the product is no longer sealable), manufacturers can only test 0.5% - 1.25% of production volume, or approximately 0.66% of production volume. Additionally, operators who are already fully occupied with other production-related tasks are only allowed limited time (e.g., about 1 - 2 minutes per sample) to perform each test. However, automating the RSF test and CF test processes can increase the test speed and the amount of product that can be tested. Precautions must be taken to ensure that samples are properly loaded into the test system and accurate measurements are ensured when automating the RSF test and CF test.

[0019] FIG. 1a shows a perspective view of an exemplary test system 100, and FIG. 1b shows a perspective view of a load frame 102 of the exemplary test system 100 with some parts omitted for clarity. The test system 100 generally includes a load frame 102, a load cell 106 attached to a crosshead 108 of the load frame 102, a platen assembly 110 in a base structure 104 of the load frame 102, and a controller 150. As will be discussed, the platen assembly 110 is configured to support one or more samples 112 during a compression test (e.g., RSF or CF test), whether through a manual process or an automated process.

[0020] As best shown in FIG. 1a, the load frame 102 includes a base structure 104, one or more columns 114, a movable crosshead 108, and a top plate 116. The load frame 102 serves as a high-rigidity support structure against which a test force (e.g., a compressive force) acts during a test (e.g., RSF test, compression friction measurement test, etc.). As shown, the load frame 102 can be composed of a single column 114, but for example, a plurality of columns 114 can be employed in a double-column configuration. The base structure 104 generally serves to support the one or more columns 114 and the platen assembly 110 that supports the sample 112 while housing various circuit parts and components such as the controller 150.

[0021] The platen assembly 110 can be manually or automatically adjusted (or otherwise controlled) to move or transfer the sample 112 to the test position, and the sample 112 is typically positioned below the test head 136, the test apparatus, or other test accessories. The sample 112 may be, for example, a container 140 for parenteral pharmaceuticals, as shown in Figure 1b. In one example, as best shown in detail A of Figure 1b, the container 140 (e.g., a bottle with a flange 144) defines an opening 142 and a flange 144. An elastomer stopper 146 covers the opening 142. A cap 148 is crimped under the flange 144, compressing the elastomer stopper 146 and sealing the opening 142. In another example, as best shown in detail B of Figure 1b, the cap 148 may be omitted, and the elastomer stopper 146 fits into the opening 142 of the container 140 (e.g., a vial) and presses against the inner surface of the container 140 to seal the opening 142. Sample 112 is shown as a container 140 with and without a flange 144 and / or cap 148, but other types of sample 112 are also conceivable.

[0022] Each of the one or more columns 114 comprises a guide column and a ball screw 154 that is driven and coupled to an actuator 156. The ball screw 154 is a form of mechanical linear actuator that converts rotational motion (e.g., from an actuator 156 such as a motor) into linear motion with little friction. In one example, the ball screw 154 may include a threaded shaft that provides a helical track for a ball bearing and acts as a precision screw. As shown in Figure 1b, the ball screw 154 is housed between the base structure 104 and the top plate 116 within one or more columns 114. The actuator 156 that drives the ball screw 154 is controlled via a controller 150. By providing a column cover 118, the ball screw 154 can be protected from dust, dirt, and damage, and the user can be protected from injury during operation. The test system 100 is equipped with various sensors to monitor its operation. For example, the test system 100 may include an upper limit switch 132 and a lower limit switch 134 to prevent the crosshead 108 from deviating from an acceptable range of motion along axis A. When the upper limit switch 132 or the lower limit switch 134 is triggered, the controller 150 can stop (or reverse) the actuator 156 to prevent damage to the test system 100 or the sample 112.

[0023] The crosshead 108 is mounted on both the guide column and the ball screw 154 and supports the load cell 106. The ball screw 154 is driven (e.g., rotates) via the actuator 156. The rotation of the ball screw 154 drives the crosshead 108 upward (away from) or downward (towards) relative to the base structure 104, while the guide column provides stability to the crosshead 108. The load cell 106 can be removably coupled to the crosshead 108 via one or more mechanical fasteners 138 (e.g., screws, bolts, cap screws, etc.) to allow the operator to replace the load cell 106 if desired. For example, the load cell 106 may be damaged, and different types of load cells 106 may be desired or required, which may vary from test to test (e.g., RSF or CF test).

[0024] The operator can monitor and / or control the operation of the test system 100 by using a display device 126 (e.g., a touchscreen display), a control panel 128, and / or a remote control unit 130 (e.g., a handset). In some examples, the control panel 128 and the remote control unit 130 may each provide one or more switches, buttons, or dials (e.g., an emergency stop button) for controlling or adjusting the operation of the test system 100. The control panel 128 and the remote control unit 130 may further provide one or more status indicators (e.g., LEDs, lights, etc.) for indicating the status of the test system 100. The remote control unit 130 may be wired or wireless.

[0025] To provide further protection and enhance safety, the load string 101 can be housed within a housing 120 that defines the test chamber 122. The housing 120 can be made from a transparent material (e.g., glass, plastic, plexiglass, etc.) to allow an operator to observe the load string 101. A door or access panel 124 may be provided to allow access to the test chamber 122 within the housing 120. The load string 101 generally refers to a component installed between the movable crosshead 108 and the base structure 104 (or, where applicable, the fixed lower crosshead). Typically, the load string 101 includes a load cell 106, a test head 136, any adapters necessary to connect the components, and the specimen(s) 112 to be tested. Typically, for an RSF test, the load cell 106 is mounted on the crosshead 108, the test head 136 with an anvil is mounted on the load cell 106, and the specimen(s) 112 are positioned on the base structure 104 (e.g., using a platen assembly 110). Similarly, in the case of a CF test, the load cell 106 is mounted on the crosshead 108, the compression rod is attached to the load cell 106, and the sample 112 is positioned on the base structure 104 (for example, using the platen assembly 110).

[0026] The operation of the test system 100 can be automatically controlled and / or monitored via the controller 150. The controller 150 may comprise a processor 150a and a memory device 150b configured to have executable instructions. The controller 150 can be operably coupled to and configured to control various actuators (e.g., an actuator 156 that drives a ball screw 154), sensors (e.g., load cells 106, upper limit switches 132 and lower limit switches 134), user interfaces (e.g., a display device 126, a control panel 128, and / or a remote control unit 130), etc.

[0027] During the RSF test, for example, the crosshead 108 moves downward (towards the base structure 104) along axis A of the load frame 102 to apply a compressive load to the specimen 112 via the test head 136, the test apparatus, or other test accessories coupled to the load cell 106. The test head 136 may be or may include an anvil (also known as a dorn) configured to contact and compress one or more specimens 112. The test head 136, the test apparatus, or other test accessories may be coupled directly to the coupler 152 of the load cell 106, or via a compression rod or pin.

[0028] The load cell 106 converts this load into an electrical signal, and the test system 100 measures this electrical signal via the controller 150 and displays it to the operator via the display device 126. In one example, the test head 136 can advance at a constant speed (e.g., about 0.01 inches / second). In other words, in this example, for every 0.001 inch the crosshead 108 advances along the column 114 (along axis A), the controller 150 automatically records the force exerted on the sample 112 in response to the motion (strain) that the test head 136 imposes on the sample 112. The constant speed can be adjusted for a given sample 112. The controller 150 also automatically records the corresponding strain data. The resulting dataset includes a sequence of stress-strain measurements that can be graphed and approximates a curve of predictable shape. In the case of RSF, a proper seal can be determined by monitoring the inflection point in the resulting curve (for example, indicating that the elastomer stopper 146 has transitioned from a bent state to a rigid state, and therefore the opening 142 has been sealed).

[0029] The test head 136 can be designed for RSF and / or CF testing. For example, the test head 136 may be a compression rod for CF testing, or a test head with an anvil, for example, an adjustable, adaptable anvil, for RSF testing. As can be understood, certain tests may require certain types of test heads 136. For example, the test head 136 used during RSF measurement may have an anvil that is sized and shaped to correspond to the size and shape of the stopper of the parenteral container. Thus, although the test head 136 is generally configured for RSF testing in Figures 1a and 1b, a compression rod (and associated load cell) can be used instead for CF testing.

[0030] The test head 136 may be interchangeable to allow the test system 100 to be used for various types of tests (e.g., RSF, CF, tension, compression, bending, etc.). In other words, the test head 136 may be configured to be detachably coupled to the load cell 106, for example via a coupler 152 or other means, to allow the operator to replace or swap the test head 136 with another test head 136, test apparatus, or other test accessories. The coupler 152 may employ one or more of the following: a collar fitting (e.g., a collar with one or more set pins or screws), a clevis fitting, a sleeve fitting, or a threaded fitting (e.g., a threaded rod). Thus, although the coupler 152 is shown as a female collar coupler with set screws and / or set pins, other types of fittings are also conceivable.

[0031] One or more samples 112 are supported on the base structure 104 by a platen assembly 110. Similar to the test head 136, certain tests may require certain types of platen assemblies 110. For example, a platen assembly 110 used during an RSF measurement may comprise one or more stations whose size and shape correspond to the size and shape of a parenteral container 140 (or other sample 112). To this end, the platen assembly 110 may comprise a test-specific or sample-specific sample plate 110a and a base plate 110b supported by the base structure 104 and configured to support the sample plate 110a. The sample plate 110a may be removably coupled to the base plate 110b to allow the operator to select a sample plate 110a suitable for a particular test. In one example, the sample plate 110a is a plate or table of a size and shape that supports one or more samples 112 (e.g., via one or more recesses), while the base plate 110b may be a plate configured to support and / or fix the sample plate 110a to the base structure 104. In some examples, the sample plate 110a is configured to move relative to the base plate 110b. For example, the sample plate 110a may be configured to rotate or tilt relative to the base plate 110b to adapt to the appropriate angle of the test head 136 during compression.

[0032] To obtain accurate RSF measurements, it is crucial that the test head 136 makes firm contact with the sample 112 (e.g., cap 148) during the RSF test. Typically, this requires the operator to check that the sample 112 is properly seated within the platen assembly 110, such that the flat surface of the cap 148 is coplanar with the contact point (e.g., anvil) of the test head 136. In automated methods, this introduces further complexity.

[0033] One option is to employ a sensor system (e.g., one or more imaging devices) to verify the correct placement of the sample 112, but the sensor system increases the cost and complexity of the overall test system 100. A lower-cost but more robust option is to use a test head 136 with an anvil that conforms to the position of the sample 112, by allowing both planar and radial motion of the anvil during the seating portion of the RSF compression test to ensure that the test head 136 makes firm contact with the sample 112 (e.g., at the cap 148).

[0034] Figure 2a shows a plan section view of a first exemplary test head 200 according to an aspect of the present disclosure. As shown, the test head 200 generally comprises a housing 202, an anvil 204, a ball-roller assembly 208, and a retaining ring 203. The ball-roller assembly 208 is configured to provide a contact point 224 between the housing 202 and the anvil 204 during RSF testing. In some examples, the retaining ring 203 is positioned within a first cavity 222 and configured to hold the anvil 204 at least partially within the first cavity 222. During RSF testing, a compressive force pushes the anvil 204 into the first cavity 222. The retaining ring 203 is configured to hold the anvil 204 at least partially within the first cavity 222 in the absence of such a compressive force. The retaining ring 203 also provides restriction to radial swivel 228 of the anvil 204 within the first cavity 222. The test head 200 defines a proximal end 218 having a first coupler 232 configured to engage with a second coupler 152 of the test system 100, and a distal end 220 having a recess 206 configured to engage with the specimen 112. The recess 206 may be sized and shaped to engage with the surface of the cap 148 of the specimen 112. In several examples, one of which is shown in Figure 2a, a washer 234 can be positioned at the contact point between the anvil 204 and the retaining ring 203 to provide or adjust restriction to the radial rotation 228 of the anvil 204 within the first cavity 222. Although not shown, the washer 234 may also be configured similarly in relation to other drawings of the test head 200.

[0035] As shown in the figure, the anvil 204 is configured to float within the first cavity 222, thereby allowing the surface of the anvil 204 to fit into the surface of the cap 148. In an automated process, for example, multiple samples 112 can be pre-loaded and / or automatically fed into or by the platen assembly 110. Such movement may result in improper seating of the samples 112 (e.g., distortion). If the contact between the anvil 204 and the cap 148 is not coplanar, the accuracy of the RSF measurement will decrease. Therefore, to ensure that the cap 148 of the sample 112 is properly seated within the recess 206 of the anvil 204, the anvil 204 is configured to move in a planar motion 226 (e.g., left and right) relative to the housing 202 and to pivot radially (228) relative to the housing 202.

[0036] In some examples, the housing 202 defines a first cavity 222, and the anvil 204 is positioned at least partially within the first cavity 222. The outer diameter of the anvil 204 can be sized to allow lateral movement of the anvil 204 in the plane within the first cavity 222. In other words, the inner diameter of the first cavity 222 can be larger than the outer diameter of the anvil 204 by a predetermined distance (D) to allow some play within the first cavity 222. The predetermined distance (D) can be, for example, 1 millimeter to 10 millimeters. When the anvil 204 is centered within the first cavity 222, as shown in Figure 2b, half the distance (D / 2) is available on both sides of the anvil 204 for planar motion 226.

[0037] The ball-roller assembly 208 generally comprises balls 210, a roller housing 212, and a plurality of ball bearings 214. The ball-roller assembly 208 can be rated to support a compressive load of 180 N. The plurality of ball bearings 214 serve to reduce friction between the balls 210 and the roller housing 212. The ball-roller assembly 208 can be positioned within a second cavity 216. For example, the ball-roller assembly 208 can be press-fitted into the second cavity 216. In the illustrated example, the housing 202 defines the second cavity 216, but other configurations are conceivable, as described in relation to Figures 3a-3c, in which an anvil 204 may define the second cavity 216. The housing 202, anvil 204, and / or balls 210 can be manufactured from metal or metal alloy, such as stainless steel.

[0038] Figures 2b and 2c show plan cross-sectional views of the first exemplary test head of Figure 2a in contact with the improperly seated specimen 112 at a first and second angle, respectively. The ball roller assembly 208 provides a single contact point 224 between the housing 202 and the anvil 204. As shown, the ball roller assembly 208 allows the anvil 204 to move relative to the housing 202 in a planar motion 226. During the RSF test, the anvil 204 can move in a planar motion 226 and / or radial motion 228 such that the recess 206 of the anvil 204 is coplanar with the specimen 112.

[0039] Figure 2d shows a plan section view of a first exemplary test head having a concave region at the contact point. Over time, a single contact point 224 may develop a wear point (e.g., a divot) on the anvil 204. As can be seen, the divot prevents the anvil 204 from floating freely, which can reduce the accuracy of the RSF measurement. To mitigate wear, the anvil 204 can define a concave region 230 at the single contact point 224, corresponding to the surface of the sphere 210, thereby increasing the contact area with the ball-roller assembly 208. Alternatively, the concave region 230 may be positioned on the housing 202 if the ball-roller assembly 208 is fixed to the anvil (e.g., as shown in Figures 3a-3c).

[0040] Figure 3a shows a plan section view of a second exemplary test head 300 according to an embodiment of the present disclosure, and Figures 3b and 3c show plan section views of the second exemplary test head 300 in contact with a sample 112 improperly seated at a first angle and a second angle, respectively. The test heads 300 in Figures 3a to 3c are substantially the same as the test heads 200 in Figures 2a to 2c, except that the anvil 204 defines a second cavity 216 in the ball roller assembly 208. In this example, the ball roller assembly 208 is press-fitted into the second cavity 216 in the anvil 204.

[0041] Figure 4a shows a perspective view of a third exemplary test head 400 according to an embodiment of the present disclosure, and Figure 4b shows a plan cross-sectional view of the third exemplary test head along section AA of Figure 4a. The test heads 400 of Figures 4a and 4b are similar to the test heads 200 and 300 in that they facilitate planar motion 226 and radial motion 228, but the test head 400 divides the planar motion 226 and radial motion 228 into two separate mechanisms. Specifically, the planar motion 226 is provided via a plurality of ball bearing assemblies 418, and the radial motion 228 is provided via a ball roller assembly 416.

[0042] The test head 400 generally comprises a first housing 402, a second housing 404, and an anvil 406. The first housing 402 defines a first cavity 412, and the second housing 404 defines a second cavity 414. The second housing 404 is positioned at least partially within the first cavity 412 and configured to move with planar motion 226 relative to the first housing 402. The anvil 406 is positioned at least partially within the second cavity 414 and configured to pivot radially (228) relative to the second housing 404. As shown in the figure, the anvil 406 is configured to pivot radially (228) relative to the second housing 404 using a ball-roller assembly 416. The ball-roller assembly 416 comprises a ball 408 and a roller housing 410.

[0043] Multiple ball bearing assemblies 418 are provided to reduce friction between the surface of the first housing 402 and the surface of the second housing 404. In some examples, as shown, the multiple ball bearing assemblies 418 are press-fitted into a cavity defined within the second housing 404, but the multiple ball bearing assemblies 418 may instead be press-fitted into a cavity defined within the first housing 402. In some examples, the ball roller assembly 416 may further include multiple ball bearings (not shown) between the balls 408 and the roller housing 410.

[0044] Figure 5 is a flowchart illustrating an exemplary method 500 for performing an automated residual seal force (RSF) test in a test system 100. The test system 100 includes a load cell 106 configured to move along a column 114 toward and away from a base structure 104 via a crosshead 108.

[0045] In step 502, multiple samples 112 are mounted on the sample plate 110a. The multiple samples 112 mounted on the sample plate 110a can be mounted through a manual or automated process. The multiple samples 112 include a first sample 112 and subsequent samples 112 (e.g., a second sample 112).

[0046] In step 504, the sample plate 110a is positioned at a first position where the first sample 112 is positioned at the test location of the test system 100. The sample plate 110a can be positioned at the first position manually (for example, by an operator before starting the test) or via an actuator.

[0047] In step 506, the actuator 156 advances the crosshead 108 along the column 114 toward the base structure 104 to compress the first sample 112.

[0048] In step 508, the processor 150a, which is operably coupled to the load cell 106, determines the residual sealing force of the first sample 112.

[0049] In step 510, the actuator 156 retracts the crosshead 108 along the column 114 away from the base structure 104.

[0050] In step 512, the sample plate 110a is moved to a second position where the subsequent sample 112 is positioned at the test location.

[0051] In step 514, the actuator 156 advances the crosshead 108 along the column 114 toward the base structure 104 to compress the subsequent sample 112.

[0052] In step 516, the processor 150a determines the residual sealing force of the subsequent sample 112.

[0053] Steps 512 to 516 can be automatically repeated for each subsequent sample 112 until each of the multiple samples 112 mounted on the sample plate 110a has been tested.

[0054] While the Method and / or System has been described with reference to certain specific embodiments, those skilled in the art will understand that various modifications and substitutions can be made without departing from the scope of the Method and / or System. In addition, many modifications can be made without departing from the scope of the Disclosure to adapt the teachings of the Disclosure to specific circumstances or materials. For example, blocks and / or components of the disclosed examples can be combined, divided, rearranged, and / or otherwise modified. Therefore, the Method and / or System is not limited to the specific embodiments disclosed. Rather, the Method and / or System includes all embodiments that fall within the scope of the appended claims, either literally or under the doctrine of equivalents. This disclosure also includes the following aspects: [Aspect 1] A test head for a residual sealing force (RSF) test system, A housing that defines the first cavity, An anvil positioned at least partially within the first cavity, A ball roller assembly configured to provide a contact point between the housing and the anvil during RSF testing, A retaining ring configured to hold the anvil at least partially within the first cavity, A test head equipped with a test head. [Aspect 2] The test head according to embodiment 1, wherein the anvil is configured to move in planar motion relative to the housing. [Aspect 3] The test head according to embodiment 1, wherein the anvil is configured to pivot radially relative to the housing. [Aspect 4] The test head according to embodiment 1, wherein the anvil is configured to move in a planar motion and radially relative to the housing. [Aspect 5] The test head according to embodiment 1, wherein the anvil is configured to float within the first cavity. [Aspect 6] The test head according to embodiment 1, wherein the ball roller assembly comprises a ball, a roller housing, and a plurality of ball bearings. [Aspect 7] The housing defines a second cavity, as described in Embodiment 1. [Aspect 8] The test head according to embodiment 7, wherein the ball roller assembly is press-fitted into the second cavity. [Aspect 9] The anvil is a test head according to embodiment 1, which defines a second cavity. [Aspect 10] The test head according to embodiment 9, wherein the ball roller assembly is press-fitted into the second cavity. [Aspect 11] The test head according to embodiment 1, wherein the retaining ring is positioned within the first cavity. [Aspect 12] The test head according to embodiment 1, wherein the anvil defines a recess configured to engage with a sample in the RSF test system. [Aspect 13] The test head according to embodiment 1, wherein the housing defines a first coupler configured to engage with a second coupler of the test system. [Aspect 14] The test head according to embodiment 1, wherein the test head defines a proximal end having a first coupler configured to engage with a second coupler of the test system, and a distal end having a recess configured to engage with a sample. [Aspect 15] The test head according to embodiment 1, wherein the housing and the anvil are manufactured from a metal or metal alloy. [Aspect 16] The test head according to embodiment 1, wherein the housing and the anvil are manufactured from stainless steel. [Aspect 17] The test head according to embodiment 6, wherein the sphere is manufactured from stainless steel. [Aspect 18] The test head according to embodiment 14, wherein the first coupler is a clevis joint or a sleeve joint. [Aspect 19] The test head according to embodiment 1, wherein the ball roller assembly provides a single contact point between the housing and the anvil. [Aspect 20] The test head according to embodiment 19, wherein the housing or the anvil defines a concave region at the single contact point that increases contact with the ball roller assembly. [Aspect 21] A test head for a residual sealing force (RSF) test system, A first housing that defines the first cavity, A second housing defining a second cavity, the second housing being at least partially positioned within the first housing and configured to move in planar motion relative to the first housing, An anvil positioned at least partially within the second cavity and configured to pivot radially relative to the second housing, A test head equipped with a test head. [Aspect 22] The test head according to embodiment 21, wherein the anvil is configured to pivot radially relative to the second housing using a ball-roller assembly. [Aspect 23] The ball-roller assembly comprises a ball and a roller housing, as described in embodiment 22. [Aspect 24] The test head according to embodiment 23, wherein the ball roller assembly further comprises a plurality of ball bearings between the ball and the roller housing. [Aspect 25] The test head according to embodiment 21, wherein the second housing is configured to move in planar motion relative to the first housing using a plurality of ball bearings. [Aspect 26] A test system for performing residual sealing force (RSF) testing, A column supported by a base structure, A load cell supported by the column, the load cell is configured to move along the column via a crosshead toward and away from the base structure, A base plate supported by the aforementioned base structure and configured to support a sample, A test head operably coupled to the load cell, The test head is equipped with, A housing that defines the first cavity, An anvil positioned at least partially within the first cavity, A ball roller assembly configured to provide a contact point between the housing and the anvil during RSF testing, A retaining ring configured to hold the anvil at least partially within the first cavity, A testing system equipped with the following features. [Aspect 27] The test system according to embodiment 26, further comprising a sample plate configured to receive the sample, wherein the sample plate is removably coupled to the base plate.

Claims

1. A test head for a residual sealing force (RSF) test system, A housing that defines the first cavity, An anvil positioned at least partially within the first cavity, A ball roller assembly configured to provide a contact point between the housing and the anvil during RSF testing, A retaining ring configured to hold the anvil at least partially within the first cavity, Equipped with, The aforementioned ball-roller assembly is a test head comprising a ball, a roller housing, and a plurality of ball bearings.

2. The test head according to claim 1, wherein the anvil is configured to move in planar motion relative to the housing.

3. The test head according to claim 1, wherein the anvil is configured to pivot radially relative to the housing.

4. The test head according to claim 1, wherein the anvil is configured to move in a planar motion and radially relative to the housing.

5. The test head according to claim 1, wherein the anvil is configured to float within the first cavity.

6. The test head according to claim 1, wherein the housing defines a second cavity.

7. The test head according to claim 6, wherein the ball roller assembly is press-fitted into the second cavity.

8. The test head according to claim 1, wherein the anvil defines a second cavity.

9. The test head according to claim 8, wherein the ball roller assembly is press-fitted into the second cavity.

10. The test head according to claim 1, wherein the retaining ring is positioned within the first cavity.

11. The test head according to claim 1, wherein the anvil defines a recess configured to engage with a sample in the RSF test system.

12. The test head according to claim 1, wherein the housing defines a first coupler configured to engage with a second coupler of the RSF test system.

13. The test head according to claim 1, wherein the test head defines a proximal end having a first coupler configured to engage with a second coupler of the RSF test system, and a distal end having a recess configured to engage with a sample.

14. The test head according to claim 1, wherein the housing and the anvil are manufactured from a metal or metal alloy.

15. The test head according to claim 1, wherein the housing and the anvil are made of stainless steel.

16. The test head according to claim 1, wherein the sphere is made of stainless steel.

17. The test head according to claim 13, wherein the first coupler is a clevis joint or a sleeve joint.

18. The test head according to claim 1, wherein the ball roller assembly provides a single contact point between the housing and the anvil.

19. The test head according to claim 18, wherein the housing or the anvil defines a concave region at the single contact point that increases contact with the ball roller assembly.

20. A test head for a residual sealing force (RSF) test system, A first housing that defines the first cavity, A second housing defining a second cavity, the second housing being positioned at least partially within the first housing and configured to move in planar motion relative to the first housing, An anvil positioned at least partially within the second cavity and configured to pivot radially relative to the second housing, Equipped with, The anvil is configured to pivot radially relative to the second housing using a ball-roller assembly. The ball-roller assembly comprises a ball and a roller housing, The ball-roller assembly further comprises a plurality of ball bearings between the ball and the roller housing, and is a test head.

21. The test head according to claim 20, wherein the second housing is configured to move in planar motion relative to the first housing using a plurality of ball bearings.

22. A test system for performing residual sealing force (RSF) testing, A column supported by a base structure, A load cell supported by the column, the load cell is configured to move along the column via a crosshead toward and away from the base structure, A base plate supported by the aforementioned base structure and configured to support a sample, A test head operably coupled to the load cell, The test head is equipped with, A housing that defines the first cavity, An anvil positioned at least partially within the first cavity, A ball roller assembly configured to provide a contact point between the housing and the anvil during RSF testing, A retaining ring configured to hold the anvil at least partially within the first cavity, Equipped with, The ball-roller assembly is a test system comprising a ball, a roller housing, and a plurality of ball bearings.

23. The test system according to claim 22, further comprising a sample plate configured to receive the sample, wherein the sample plate is removably coupled to the base plate.

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