Patent Publication Number: US-2021187454-A1

Title: Container rotation device

Description:
BACKGROUND 
     Automated analytical instruments or analyzers are used to test patient samples (e.g., blood, plasma, or serum samples) to determine if the patient suffers from a disease. Containers (e.g., tubes) each having a sample are held upright in racks and are automatically transported to a testing station. Due to the large number of samples, information about each sample container is coded into a barcode which is printed on a label that is affixed to the container. The barcode is read by a barcode reader to identify the sample prior to being tested. In some cases, the container may need to be rotated so that the barcode can be read by the barcode reader. The container may also need to be rotated to mix the sample to, for example, resuspend particulates that have settled in the container. Prior solutions to this problem utilized two motors to rotate containers. 
     SUMMARY 
     Described herein are devices and methods for rotating a container (e.g., a capped tube containing a sample). The disclosure provides devices and methods of rotating a container using one motor, resulting in a less complex device. The device moves and rotates a container rotating member which in turn is used to rotate a container. The devices can be used in automated analytical instruments (e.g., automated blood analyzers) that automatically transport and detect the identity of sample containers. The devices can also be used in instruments that automatically spin sample containers to mix or homogenize the sample. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a simplified schematic side view of a container rotating device according to an embodiment. 
         FIG. 2  is a perspective view of the container rotating device of  FIG. 1 . The device is shown without a container in a holder. 
         FIG. 3  is a cross-sectional side view of a container engaging member according to an embodiment. The device is shown without a mounting stand. 
         FIG. 4  is a cross-sectional side view of a portion of a container engaging member according to an embodiment. 
         FIGS. 5A-5E  illustrate side views of the container rotating device of  FIGS. 1-3  during various stages of operation. 
     
    
    
     DETAILED DESCRIPTION 
     In an embodiment, a container rotation device comprises a linear actuator having a motor operably connected to a first end of a lead screw and slidably mounted on a vertical linear guide. The motor is configured to rotate the lead screw. A container engaging member is operably connected to a second end of the lead screw and is positioned above a container supported by a holder. A nut is threaded onto helical threads on the lead screw. The nut is slidably mounted on the vertical linear guide between the motor and the container engaging member. The container rotation device further includes a stop for stopping movement of the nut toward the container engaging member. A controller controls the operation of the motor. Responsive to operation of the motor, the container engaging member is moveable between a first position in which the container engaging member is rotatably engaged with the container and a second position in which the container engaging member is disengaged from the container. 
     In an embodiment, a method of rotating a container comprises activating a motor to rotate a lead screw in a first direction toward the container. The next step of the method comprises rotating the lead screw in the first direction, thereby rotating and moving the container engaging member toward the container until the container engaging member engages the container in the first direction. The next step of the method comprises rotating the container in the first direction with the container engaging member. 
     Rotation of the container provides one or both of the following effects: mixing of the contents until the contents are sufficiently mixed and/or bringing a barcode on the container into a read position (i.e., facing the barcode reader). 
       FIGS. 1-3  illustrate a device  100  for rotating a container  102  (e.g., a capped vacutainer tube) containing a sample (e.g., patient blood, plasma, or serum). The device  100  can be used in a system configured to analyze patient samples. The device  100  comprises a linear actuator, a container engaging member  104 , a nut  106 , and a controller  108 . The linear actuator (e.g., a motorized lead screw) comprises a motor  110  operably connected to a first end of a lead screw  112  and is slidably mounted on a vertical linear guide  114 . The motor is configured to rotate the lead screw  112 . As shown in  FIGS. 1-3 , the motor  110  is coupled to a first carriage  116  (e.g., an L-bracket) that is attached to a first slide  117  between two vertical rails  118  in the linear guide  114 . The first carriage  116  constrains the motor  110  from rotating with the lead screw  112 . In some embodiments, the motor  110  is a stepper motor. Other possible motors  110  include dc brush and dc brushless motors. In some embodiments, screws are used to attach the motor  110  to the first carriage  116  and to attach the first carriage  116  to the first slide  117 . 
     The container engaging member  104  is operably connected to a second end of the lead screw  112  and is positioned above the container  102  supported by a holder  118 . The length of the lead screw  112  can be adjusted to accommodate the height of the container  102 . Responsive to operation of the motor, the container engaging member  104  is moveable between a first position in which the container  102  engaging member  104  is rotatably engaged with the container  102  and a second position in which the container engaging member  104  is disengaged from the container  102 . 
     The container engaging member  104  is substantially cylindrical in shape. Referring to  FIG. 4 , an inner surface  120  of the container engaging member  104  is tapered to accommodate different container shapes and sizes. In some embodiments, the inner surface  120  has a frustoconical shape. In some embodiments, at least a portion of the container engaging member  104  is formed from a resiliently deformable material. As shown in  FIGS. 1 and 2 , the container engaging member  104  comprises two portions: a first portion  122  that is attached to the lead screw  112  and a second portion  124  that contacts the container  102 . The first portion  122  can be formed from a non-deformable material (e.g., aluminum, steel) and the second portion  124  can be formed from a resiliently deformable material. In some embodiments, substantially the entire container engaging member  104  is formed from a resiliently deformable material. Resiliently deformable material includes, but is not limited to, an elastomeric material, a polymeric material, a polyurethane material, a latex material, and a silicone material. Depending on the material from which the container engaging member  104  is made, the container engaging member  104  can be attached to the lead screw  112  by threading internal threads onto external lead screw threads or by soldering the two components together. 
     Referring again to  FIGS. 1-3 , the nut  106  is threaded onto helical threads on the lead screw  112  (i.e., the nut  106  has internal threads corresponding to the external lead screw threads) and is slidably mounted on the vertical linear guide  114  between the motor  110  and the container engaging member  104  via a second carriage  128  that is attached to a second slide  129  between the two vertical rails  118  in the linear guide  114 . The second carriage  128  can be an L-bracket. The second carriage  128  constrains the nut  106  from rotating on the lead screw  112 . In some embodiments, screws are used to attach the nut  106  to the second carriage  128  and to attach the second carriage  122  to the second slide. The nut  106  does not have to be any particular shape. 
     Slidably mounting both the motor  110  and the nut  106  on the linear guide  114  allows both the motor  110  and the nut  106  to move independent of each other and accommodates different container heights. 
     The device  100  further comprises a stop  130  marking the end of a distance moveable by the nut  106  on the linear guide  114  such that the nut  106  does not collide with the container engaging member  104  and such that the container engaging member  104  is positioned above the container  102 . 
     The holder  118  (e.g., a test tube rack) holds a plurality of containers in an upright position in a plurality of bores. The holder  118  is configured to move along a container processing path in an automated instrument. Each of the bores in the holder  118  comprises an opening through which a barcode  126  affixed to an outer circumferential surface of the container is readable by a barcode reader  127 . The barcode  126  has identifying information about the sample in the container  102 . The holder  118  can be one of a plurality of holders in a sample rack that accommodates a plurality of sample containers (e.g., ten or more containers). The holder  118  can be transported with the container(s) to a location in an automated analyzer at which each of the barcodes on the containers can be read. 
     The controller  108  controls the operation of the motor  110 . In embodiments, the controller  108  controls operation of the motor  110  and is embodied in hardware or software. In some embodiments, the controller  108  sends signals to the motor  110  to rotate the lead screw  112  in a forward or reverse direction. The controller  108  can be operably connected to an automated analyzer that includes control circuitry configured to control operation of the motor  110  along with other components (e.g., the barcode reader  127 ) of the automated analyzer. The controller  108  can also be operably connected to a network that controls operation of multiple automated analyzers. 
     Referring to  FIG. 5A , in operation of the container rotation device  100 , the linear actuator is actuated, causing the motor  110  to transmit a rotational force to the lead screw  112  which in turn rotates the container engaging member  104  in a first (or forward) direction. While rotating, the lead screw  112  threads through the nut  106  which is resting on the stop  130  and the action of the lead screw  112  threading through the nut  106  causes the linear actuator to move down toward the container  102 . The container engaging member  104  concurrently rotates and moves toward the container  102  until the container engaging member  104  engages the container  102  in the first direction ( FIG. 5B ). As the container engaging member  104  engages the container  102 , a frictional force between the container engaging member  104  and the container  102  causes the container  102  to rotate in the first direction (i.e., in the same direction as the container engaging member  104 ). In some embodiments, the step of rotating the container  102  in the first direction with the container engaging member  104  comprises rotating the container  102  and the container engaging member  104  substantially along an axis of the container  102 . An axial force applied to the container  102  by the container rotation device  100  corresponds to the weight of the device components slidably mounted on the linear guide  114 . Thus, the heavier the device components, the greater the axial force is applied to the container  102 . 
     When the container engaging member  104  engages and rotates the container  102 , the second carriage  128  holding the nut  106  moves up along the lead screw  112  toward the motor  110 . Thus the rotating lead screw  112  and the motor  110  no longer move towards the container  102 . In some embodiments, the second carriage  128  is detected by a first sensor (e.g., an optical switch) at a predetermined location on the linear guide  114 . In an embodiment utilizing the first sensor, the barcode reader  127  optionally only turns on to attempt to read the barcode  126  once the first sensor detects the second carriage  128 . When the second carriage  128  is detected by the first sensor, the barcode reader  127  reads the barcode  126  and/or the sample in the container  102  is mixed by rotating the container  102  for a threshold amount of time and/or at a threshold number of revolutions per minute. 
     In an embodiment in which the motor is a stepper motor, the number of steps required for the container engaging member  104  to engage the container  102  can be programmed into the controller and when the number of steps has been reached, the barcode reader  127  reads the barcode  126  and/or the sample in the container  102  is mixed by rotating the container  102  for a threshold amount of time and/or at a threshold number of revolutions per minute. In such an embodiment, the first sensor is not needed for the purpose of signaling the barcode reader  127 . 
     In some embodiments, the barcode reader  127  attempts to read the barcode  126  while the container  102  is being rotated. In certain embodiments, the barcode reader  127  attempts to read the barcode  126  after the container  102  is no longer being rotated. For example the container  102  is rotated about 90 degrees and then the barcode reader  127  attempts to read the barcode  126 . If reading of the barcode  126  is unsuccessful, the process of rotating the container  102  and attempting to read the barcode  126  is repeated until the barcode  126  is successfully read. In some embodiments, the container  102  is rotated about 60-120 degrees one or more times during the barcode reading process. In some embodiments, the barcode reader  127  is turned off after the barcode  126  is successfully read. 
     After the barcode  126  has been successfully read and/or the sample in the container  102  has been mixed, the controller  108  sends a signal to the motor  110  to change the direction of rotation of the lead screw  112  such that the lead screw  112  is rotated in a second (or reverse) direction. Rotating the lead screw  112  in the second direction causes the container engaging member  104  to rotate in the second direction which also causes the container  102  to rotate in the second direction. The lead screw  112  now is threading through the nut  106  in an opposite direction resulting in the second carriage  128  moving in the opposite direction of the motor. In certain embodiments, when the container  102  is rotated in the second direction, the barcode  126  is read at least one additional time. 
     The second carriage  128  moves away from the motor until it reaches the stop  130  ( FIG. 5C ). After the second carriage  128  reaches the stop  130 , the nut  106  is now stationary and thus the threading of the lead screw  112  through the nut  106  now results in the motor  110  moving away from the container  102  ( FIG. 5D ). The container engaging member  104  disengages from the container  102  and the motor  110  continues to move away from the container  102  until it reaches its “home” position on the linear guide  114  ( FIG. 5E ). In an embodiment in which the motor is a stepper motor, the number of steps required to reach the home position can be programmed into the controller software and when the number of steps has been reached, the controller  108  stops actuation of the motor  110 . Additionally or alternatively, a second sensor (e.g., an optical switch) located at the home position for the motor  110  detects the first carriage  116  and sends a signal to the controller  108  indicating that the first carriage  116  has reached its home position. In response to the received signal, the controller  108  stops the motor  110 . 
     Also provided is a computer-implemented method of rotating a container  102 . The computer-implemented method of rotating the container  102  comprises sending a first signal to the motor  110  to rotate the lead screw  112  in a first direction toward the container  102  and determining that a container engaging member  104  is engaging the container  102  in the first direction and is thereby rotating the container  102  in the first direction. In some embodiments, the determining step comprises receiving a first sensor signal from a first sensor indicating that a second carriage  128  slidably mounted on the vertical linear guide  114  between the motor  110  and the container engaging member  104  and having the nut  106  coupled thereon has moved up to a predetermined location on the linear guide  114  to thereby detect when the container engaging member  104  has rotated the container  102  in the first direction. In certain embodiments, the determining step comprises determining that a stepper motor has been activated for a predetermined number of steps. In some embodiments, the method further comprises rotating the container  102  in the first direction until a sample therein is mixed for a threshold amount of time and/or at a threshold number of revolutions per minute. In some embodiments, the method further comprises sending a second signal to a barcode reader  127  to read data encoded in a barcode  126  on the container  102 . Responsive either to receiving the data from the barcode  126  or the container  102  being rotated for a threshold amount of time or number of turns, a third signal is sent to the motor  110  to rotate the lead screw  112  in a second direction which results in disengaging the container engaging member  104  from the container  102 . In certain cases, responsive to receipt of the data from the barcode  126  at the controller  108 , the controller  108  turns off the bar code reader  127 . 
     The motor  110  continues turning in the second direction until the controller  108  determines that the motor  110  has reached the home position on the linear guide  114 . Examples of determining that the motor  110  has reached the home position include the controller  108  receiving a second sensor signal from a second sensor when the motor  110  has reached the home position on the linear guide  114  and determining that a stepper motor has been activated for a predetermined number of steps. 
     All patents, patent applications, and other published reference materials cited in this specification are hereby incorporated herein by reference in their entirety. 
     ADDITIONAL DISCLOSURE AND CLAIMABLE SUBJECT MATTER 
     Item 1. A container rotation device comprising:
         a linear actuator having a motor operably connected to a first end of a lead screw and slidably mounted on a vertical linear guide, wherein the motor is configured to rotate the lead screw;   a container engaging member operably connected to a second end of the lead screw;   a nut threaded onto helical threads on the lead screw, wherein the nut is slidably mounted on the vertical linear guide between the motor and the container engaging member;   a stop marking one end of a distance moveable by the nut on the linear guide; and   a controller for controlling operation of the motor,   wherein, responsive to operation of the motor, the container engaging member is moveable between a first position and a second position.       

     Item 2. The container rotation device of Item 1, wherein the motor is a stepper motor. 
     Item 3. The container rotation device of Item 1 or 2, wherein the motor is coupled to a first carriage that is attached to a first slide between two vertical rails on the vertical linear guide. 
     Item 4. The container rotation device of Item 1, wherein the nut is coupled to a second carriage that is attached to a second slide between two vertical rails on the vertical linear guide. 
     Item 5. The container rotation device of any one of Items 1-4, wherein an inner surface of the container engaging member is tapered. 
     Item 6. The container rotation device of any one of Items 1-4, wherein an inner surface of the container engaging member comprises a frustoconical shape. 
     Item 7. The container rotation device of any one of Items 1-6, wherein at least a portion of the container engaging member is formed from a resiliently deformable material. 
     Item 8. The container rotation device of Item 7, wherein the resiliently deformable material is selected from the group consisting of an elastomeric material, a polymeric material, a polyurethane material, a latex material, and a silicone material. 
     Item 9. The container rotation device of any one of Items 1-8, further comprising a sensor. 
     Item 10. The container rotation device of Item 9, wherein the sensor is an optical sensor. 
     Item 11. A method of rotating a container, the method comprising:
         providing:
           a motor operably connected to a first end of the lead screw and slidably mounted on a vertical linear guide;   a container engaging member operably connected to a second end of the lead screw;   a nut threaded onto helical threads on the lead screw, slidably mounted on the vertical linear guide between the motor and the container engaging member, and resting on a stop marking an end of a distance moveable by the nut on the linear guide;   
           actuating the motor to rotate the lead screw in the first direction and through the nut, thereby moving the container engaging member toward the container until the container engaging member engages the container in the first direction; and   rotating the container in the first direction with the container engaging member, thereby causing the nut to move along the linear guide up toward the motor.       

     Item 12. The method of Item 11, wherein the step of rotating the container in the first direction with the container engaging member comprises rotating the container and the container engaging member substantially along an axis of the container. 
     Item 13. The method of Item 11 or 12, wherein the step of activating the motor in a first direction comprises activating a stepper motor for a preprogrammed number of steps to engage the container engaging member with the container. 
     Item 14. The method of Item 11 or 12, further comprising detecting when a second carriage slidably mounted on the vertical linear guide between the motor and the container engaging member and having the nut coupled thereon has moved to a predetermined location on the linear guide having a first sensor to thereby detect when the container engaging member has rotated the container in the first direction. 
     Item 15. The method of any one of Items 12-14, further comprising rotating the container in the first direction until a sample therein is mixed for a threshold amount of time and/or at a threshold number of revolutions per minute. 
     Item 16. The method of any one of Items 12-14, further comprising rotating the container in the first direction while attempting to read a barcode on the container. 
     Item 17. The method of any one of Items 12-14, further comprising rotating the container in the first direction about 60-120 degrees followed by attempting to read a barcode on the container. 
     Item 18. The method of any one of Items 12-14, further comprising rotating the container in the first direction about 90 degrees followed by attempting to read a barcode on the container. 
     Item 19. The method of Item 17 or 18, wherein the steps of rotating the container and attempting to read the barcode are repeated until the barcode is successfully read. 
     Item 20. The method of Item 19, further comprising turning off the barcode reader after the barcode is successfully read. 
     Item 21. The method of any one of Items 11-20, further comprising:
         actuating the motor to rotate the lead screw in a second direction which is the reverse of the first direction, thereby rotating the container engaging member in the second direction; and   disengaging the container engaging member from the container.       

     Item 22. The method of Item 21, wherein the step of rotating the container engaging member in the second direction causes the container to rotate in the second direction. 
     Item 23. The method of Item 21 or 22, further comprising detecting when the motor is in a home position by detecting when a first carriage has reached a predetermined location on the linear guide having a second sensor. 
     Item 24. The method of Item 21 or 22, further comprising determining when the motor is in a home position by determining when a stepper motor has been activated for a predetermined number of steps. 
     Item 25. The method of Item 22, further comprising reading the barcode on the container at least one additional time while the container is rotated in the second direction. 
     Item 26. A computer-implemented method of rotating a container comprising:
         sending a first signal to a motor to rotate a lead screw in a first direction toward the container, wherein the motor is operably connected to a first end of the lead screw and is mounted on a first carriage which in turn is slidably mounted on a vertical linear guide, a container engaging member is operably connected to a second end of the lead screw, a nut is threaded onto helical threads on the lead screw, is slidably mounted on the vertical linear guide between the motor and the container engaging member, and is resting on a stop marking an end of a distance moveable by the nut on the linear guide; and   determining that the container engaging member is engaging the container in the first direction and is thereby rotating the container in the first direction.       

     Item 27. The method of Item 26, wherein the determining step comprises receiving a signal from a first sensor indicating that a second carriage slidably mounted on the vertical linear guide between the motor and the container engaging member and having the nut coupled thereon has moved up to a predetermined location on the linear guide to thereby detect when the container engaging member has rotated the container in the first direction. 
     Item 28. The method of Item 26, wherein the determining step comprises determining that a stepper motor has been activated for a predetermined number of steps. 
     Item 29. The method of any one of Items 26-28, further comprising rotating the container in the first direction until a sample therein is mixed for a threshold amount of time and/or at a threshold number of revolutions per minute. 
     Item 30. The method of any one of Items 26-29, further comprising:
         sending a second signal to a barcode reader to read data encoded in a barcode on the container;   responsive to either receiving data from the barcode or the container being rotated for a threshold amount of time or number of turns, sending a third signal to the motor to rotate the lead screw in a second direction which results in disengaging the container engaging member from the container.       

     Item 31. The method of Item 30, further comprising turning off the barcode reader responsive to receiving data from the barcode. 
     Item 32. The method of Item 30 or 31, further comprising continuing to rotate the lead screw in the second direction with the motor until the controller determines that the motor has reached a home position on the linear guide. 
     Item 33. The method of Item 32, wherein the controller determines when the motor has reached the home position on the linear guide by receiving a signal from a second sensor. 
     Item 34. The method of Item 32, wherein the controller determines when the motor has reached the home position by determining when a stepper motor has been activated for a predetermined number of steps.