Thrombectomy system with linear magnetic encoder motion detection function

Abstract

The thrombectomy system includes a stroke length detection assembly. An exemplary drive unit for the thrombectomy system may include one or more panels enclosing the internal structure of the drive unit, a vertically positioned reciprocating linear actuator assembly extending between one or more support structures in the upper region of the drive unit and fixed to a mounting plate and an actuator shaft, a bracket including a first portion extending parallel to the longitudinal axis of the actuator shaft and a second portion extending perpendicularly thereto and coupled to the actuator shaft, a magnetic strip fixed to the surface of the first portion of the bracket, and a magnetic sensor positioned adjacent to the first end region of the bracket. The magnetic sensor may be configured to measure the relative position of the actuator shaft.

Description

Technical Field

[0001] The present disclosure relates to a thrombus removal system. More specifically, the present disclosure relates to a thrombus removal system having a linear magnetic encoder movement detection function for measuring the position of an actuator.

Background Art

[0002] Thrombus removal is a procedure for removing thrombi from a patient's vasculature. Mechanical systems and fluidic systems can be utilized to remove thrombi. In a fluidic system, an infusion fluid can be injected into the treatment area of a blood vessel using a catheter to remove a thrombus. In some cases, an effluent fluid (e.g., the infusion fluid and / or blood) containing the removed thrombus may be extracted from the blood vessel through the catheter. There is a continuing need to provide alternative configurations of thrombus removal catheters and systems, and methods of operating such thrombus removal systems, in known thrombus removal systems and methods.

Summary of the Invention

[0003] The present disclosure provides alternatives for the design, materials, manufacturing methods and use of medical devices. In a first embodiment, a drive unit for a thrombus removal system includes one or more panels surrounding the internal structure of the drive unit, and a reciprocating linear actuator assembly disposed in a vertical direction extending between at least one support structure in an upper region of the drive unit, the reciprocating linear actuator assembly including an actuator shaft, a bracket coupled to the actuator shaft and movable with the actuator shaft, the bracket including a first portion extending parallel to the longitudinal axis of the actuator shaft, a magnetic strip fixed to a surface of the first portion of the bracket, and a magnetic sensor disposed adjacent to a first end region of the bracket. The magnetic sensor may be configured to measure the relative position of the actuator shaft.

[0004] In an alternative or additional example to any of the above embodiments, the magnetic sensor may be fixed within a housing that is fixed to the upper surface of the mounting plate. In an alternative or additional example to any of the above embodiments, the magnetic sensor may be mounted on a printed circuit board.

[0005] In an alternative or additional example to any of the above embodiments, the first portion of the bracket may be configured to extend through an opening in the mounting plate.

[0006] In an alternative or additional example to any of the above embodiments, the magnetic strip may be positioned between the bracket and the magnetic sensor. In an alternative or additional example to any of the above embodiments, the magnetic strip may include multiple pairs of north poles and south poles.

[0007] In an alternative or additional example to any of the above embodiments, the multiple pairs of north and south poles may extend along the entire length of the magnetic strip. In an alternative or additional example to any of the above embodiments, the magnetic sensor may include a system-on-a-chip.

[0008] In an alternative or additional example to any of the above embodiments, the magnetic sensor may be configured to output signals A and B. Alternatively or in addition to any of the above embodiments, in another example, if the signal A rises from 0 to 1 while the signal B is 0, the actuator shaft may move in the first direction.

[0009] Alternatively or in addition to any of the above embodiments, in another example, if signal B rises from 0 to 1 while signal A is 0, the actuator shaft may move in a second direction opposite to the first direction.

[0010] In an alternative or additional example to any of the above embodiments, the magnetic sensor may add to the rising edge count when the actuator shaft moves in the first direction, and may subtract from the rising edge count when the actuator shaft moves in the second direction.

[0011] In an alternative or additional example to any of the above embodiments, the count of the rising edge may be directly correlated with the distance traveled by the actuator shaft.

[0012] In an alternative or additional example to any of the above embodiments, the magnetic strip may have an overall length substantially equal to or greater than the stroke length of the actuator shaft.

[0013] In an alternative or additional example to any of the above embodiments, the magnetic strip may move linearly in direct proportion to the linear movement of the actuator shaft. In an alternative example, a drive unit for a thrombectomy system may include one or more panels enclosing the internal structure of the drive unit, and a vertically positioned reciprocating linear actuator assembly extending between at least one support structure in the upper region of the drive unit, the reciprocating linear actuator assembly including an actuator shaft, a housing, a magnetic sensor fixed within the housing, and a bracket coupled to the actuator shaft and movable in direct proportion to the actuator shaft, the bracket including a first portion extending parallel to the longitudinal axis of the actuator shaft, and a magnetic strip including a plurality of pairs of north and south poles, fixed to the surface of the first portion of the bracket between the bracket and the magnetic sensor. The magnetic sensor may be configured to add or subtract an incremental pulse count as the magnetic strip moves with the actuator shaft, and to determine the distance the actuator shaft has moved relative to a mechanical zero position based on the incremental pulse count.

[0014] In an alternative or additional example to any of the above embodiments, the magnetic sensor may be configured to output an A incremental pulse signal and a B incremental pulse signal.

[0015] In an alternative or additional example to any of the above embodiments, the magnetic sensor may increment the count of incremental pulses when the actuator shaft moves in a first direction, and may decrement the count of incremental pulses when the actuator shaft moves in a second direction opposite to the first direction.

[0016] In an alternative or additional example to any of the above embodiments, the magnetic strip may be positioned at a distance of 0.6 millimeters or less from the magnetic sensor. In another example, a method for determining the travel distance of an actuator shaft in a drive unit for a thrombectomy system may include detecting the mechanical zero position of the actuator shaft with respect to a magnetic strip; adding an incremental pulse count as the magnetic strip moves with the actuator shaft in a first direction; subtracting an incremental pulse count as the magnetic strip moves with the actuator shaft in a second direction opposite to the first direction; determining the distance and direction traveled by the actuator shaft based on the incremental pulse count; and outputting the distance and / or direction to a user interface.

[0017] The above summary of exemplary embodiments is not intended to describe each of the disclosed embodiments or any embodiment of this disclosure. [Brief explanation of the drawing]

[0018] This disclosure will be better understood by considering the detailed description of the various embodiments shown in the accompanying drawings. [Figure 1] An exemplary perspective view of a thrombectomy system. [Figure 2] Figure 1 shows a partially exploded perspective view of the pump / catheter assembly used in the thrombectomy system, including the pump, bubble trap, connecting manifold assembly, and associated instruments. [Figure 3] Figure 1 shows a partially exploded side view of the pump / catheter assembly used in the thrombectomy system, including the pump, bubble trap, connecting manifold assembly, and associated instruments. [Figure 4] A top-down perspective view of the drive unit, showing the panels and other exterior components removed, and other components located within the drive unit. [Figure 5] Front view of an exemplary reciprocating linear actuator assembly. [Figure 6]Partial front perspective view of the reciprocating linear actuator assembly shown in FIG. 5 with the mounting bracket removed. [Figure 7] Partial rear perspective view of the reciprocating linear actuator assembly shown in FIG. 5. [Figure 8] Partial front perspective view of the reciprocating linear actuator assembly shown in FIG. 5 with the mounting bracket removed and the actuator shaft moved axially or raised. [Figure 9] Front view of a portion of the magnetic strip adjacent to the magnetic sensor and multiple electrical outputs from the magnetic sensor. [Figure 10] Schematic graph showing incremental pulse output when the magnetic strip moves relative to the magnetic sensor.

[0019] The present invention is capable of accepting various modifications and alternative forms, and the details thereof are shown and described in the drawings by way of illustration. However, it should be understood that the intention is not limited to the disclosure of the specific embodiments described. In contrast, the intention is to cover all modifications, equivalents, and alternatives within the spirit and scope of the present disclosure.

Mode for Carrying Out the Invention

[0020] All numerical values, whether or not explicitly stated, are considered herein to be modified by the term "about". The term "about" generally refers to a range of numerical values that a person skilled in the art would consider equivalent to the recited value (e.g., having similar functions or results). In many instances, the term "about" also indicates a value rounded to the significant digits.

[0021] The recitation of numerical ranges by endpoints includes all numerical values within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5). Although suitable dimensions, ranges, and / or values ​​for various components, features, and / or specifications are disclosed, those skilled in the art will understand that desired dimensions, ranges, and / or values ​​may deviate from those explicitly disclosed, as suggested by this disclosure.

[0022] In this specification and the appended claims, the singular forms "a," "an," and "the" include the plural form unless explicitly stated otherwise. In this specification and the appended claims, the term "or" is generally used to include "and / or" unless explicitly stated otherwise.

[0023] The following detailed description should be read in reference to drawings in which similar components are assigned the same number in different drawings. The detailed description and drawings are not necessarily shown to scale and illustrate exemplary embodiments, and are not intended to limit the scope of this disclosure. The illustrated exemplary embodiments are intended to be typical examples only. Features selected in any exemplary embodiment may be incorporated into other embodiments unless explicitly stated otherwise.

[0024] Thrombectomy catheters and thrombectomy systems may be used to remove thrombi, plaque, lesions, blood clots, etc., from veins or arteries. The control console or drive unit of the thrombectomy system may include a linear actuator that drives a pump for supplying high-pressure saline to the thrombectomy catheter. In some drive units, a fixed position sensor may be used to measure the stroke length of the actuator, in which case the actuator may limit the system to the detection of a single stroke length. The present disclosure is a stroke length detection system that allows pump systems with different stroke lengths to be used with the same drive unit.

[0025] Figure 1 is a perspective view of an exemplary thrombectomy system 10. The thrombectomy system 10 may include a control console or drive unit 12 and a pump / catheter assembly 14. In some cases, the pump / catheter assembly 14 may be a single-use device, in which a new pump / catheter assembly 14 may be used with the drive unit 12 for each medical procedure. Shown on the drive unit 12 are a number of removable panels 16a-16n surrounding and along the drive unit 12, enclosing the internal structure of the drive unit 12. The exemplary drive unit 12 and pump / catheter assembly 14 are described in U.S. Patent No. 7,935,077, titled “THROMBECTOMY CATHETER DEPLOYMENT SYSTEM,” which has been assigned to the assignee of the present invention, and the disclosure thereof is incorporated herein by reference. Located in the center of the drive unit 12 and aligned with the lower region of panel 16g, there may be automatically opening loading bay door assemblies 20a, 20b, which open to expose the interior of the drive unit 12 in order to provide access to the transport assembly 22. The transport assembly 22, which can accommodate the components of the pump / catheter assembly 14, is made accessible by opening the closed door assemblies 20a, 20b. The drive unit 12 may include a collection container for collecting fluid leaks from the components of the pump / catheter assembly 14. For example, a drip tray 24 is located on the front of the drive unit 12 and is shown extending from the bottom of the transport assembly 22 toward panel 16a. Other configurations of the collection container are also possible. The drip tray 24 and receptacle 26 may jointly support and accommodate a drainage collection bag, such as a drainage collection bag 28 of the pump / catheter assembly 14. In other examples, the drive unit 12 may include different structures, such as a hook for suspending the drainage collection bag 28 or a shelf for mounting the drainage collection bag 28 on top. The discharged waste liquid tube 68 may be placed inside a roller pump 40 between multiple tube guides, together with the discharged waste liquid collection bag 28 connected to the discharged waste liquid tube 68.The drain fluid collection bag 28 may be appropriately positioned to collect drain fluid during medical procedures. The pump rollers (not shown) of the roller pump 40 may be rotatably engaged with the drain fluid tube 68 to control the flow of drain fluid to the drain fluid collection bag 28 through the drain fluid tube 68.

[0026] In examples where the transport assembly 22 is movable, a transport assembly operating switch (not explicitly shown) may be provided on the drive unit 12 so as to be located on panel 16g to selectively position the transport assembly 22 inward or outward. In other examples, the transport assembly 22 may be positioned using a user interface 32. The user interface or control panel 32, including memory and / or processing capabilities, may be provided on the drive unit 12 so as to be located in the upper area of ​​the drive unit 12 between the upper areas of the upper side panels 16e and 16f. The user interface 32 may be a guided user interface (GUI) including a touchscreen display that allows the user to provide input to the user interface 32 and view information on the same display screen. However, this is not required. In other examples, the user input area may be separate from the display screen. Saline bag hooks 34 and 36 may extend through panels 16e and 16f and from there to suspend saline bags. The drive unit 12 may include, in addition to the steering wheel 42, a plurality of wheels 52a to 52n and a brake pedal 54 for locking the wheels, to assist a medical professional in operating the drive unit 12.

[0027] The pump / catheter assembly 14, a disposable, single-use device, is shown not attached to the drive unit 12. The pump / catheter assembly 14 includes a pump 56 and a thrombectomy catheter 58. During use, a portion of the pump / catheter assembly 14 may be fixed within a portion of the drive unit 12. Other components included in the pump / catheter assembly 14 may include a bubble trap 60, a connecting manifold assembly 62, a drain return tube 66, a high-pressure fluid supply tube 64 (see, for example, Figure 2), a transfer fixture 69, a drain waste tube 68, and a fluid supply tube 70. The bubble trap 60 is attached to the pump 56. The connecting manifold assembly 62 is connected to the bubble trap 60. The drain return tube 66 is connected between the connecting manifold assembly 62 and the thrombectomy catheter 58. The high-pressure fluid supply tube 64 is attached between the output of the pump 56 and the thrombectomy catheter 58. The high-pressure fluid supply tube 64 may be coaxially positioned inside the drain return tube 66. The transfer fixation device 69 is located between the distal end of the drainage return tube 66 and the proximal end of the thrombectomy catheter 58. The drainage waste tube 68 connects the drainage collection bag 28 to the connecting manifold assembly 62. The fluid supply tube 70 has a bag spike 71 that connects the fluid supply bag 72 (e.g., a saline bag) to the connecting manifold assembly 62. The fluid supply tube 70 may be in fluid communication with the inside of the bubble trap 60 to supply fluid from the fluid supply bag 72 to the pump 56 and further to the thrombectomy catheter 58 through the high-pressure fluid supply tube 64.

[0028] Figure 2 is a partially exploded perspective view of the various components of the pump / catheter assembly 14, including the pump 56, bubble trap 60, connecting manifold assembly 62, and fixture 140 in general. The pump 56 is centered on a tubular body 112. Multiple components are arranged around the lower region of the tubular body 112 and include a base 109 having an upper member 110 and a lower member 111, both of which are arranged around the lower region of the tubular body 112. The upper surface of the upper member 110 of the base 109 includes an annular surface 117 that makes close contact with the capture tab of the transport assembly 22 to house the pump 56 into the transport assembly 22. The upper body 114 is arranged around the upper region of the tubular body 112. The base 109 and the upper body 114, as well as the connecting panel 115, may be molded to cover a large portion of the tubular body 112, or otherwise appropriately configured. A data plate 113 may be included in the upper body 114 to contain a barcode, RFID tag, or other information display for identifying the operating parameters of the device. The pump 56 may include a hemispherical pump piston head 116 having a flexible boot 118. The flexible boot 118 may be connected to and extend between the upper body 114 and the pump piston head 116.

[0029] In some cases, the geometrically configured lower member 111 of the base 109 may function as a member for attaching one end of the bubble trap 60 (see, for example, Figure 3). The connecting manifold assembly 62 may be directly fixed to the other end of the bubble trap 60 and may also include a bracket 120. A vertically positioned tubular manifold 148 may be attached to the bracket 120. The tubular manifold 148 may have a plurality of ports. The plurality of ports may be attached to or formed on the tubular manifold 148. The plurality of ports may include a fluid (e.g., saline) injection port 122, a discharge port 124, a Luer-type discharge return port 126, and / or an auxiliary port 128, and a cap 130. Connectors 132 and 134 extending to connect the connecting manifold assembly 62 to the upper member 110 of the base 109 are also shown.

[0030] The bubble trap 60 may include a pair of connecting halves, one of which is shown as a connecting half 60a. The hydrophobic filter 136 may be included in the upper front region of the connecting half 60a of the bubble trap. Another hydrophobic filter may be included on the connecting half of the second bubble trap (not explicitly shown), facing away from the hydrophobic filter 136 on the connecting half 60a of the bubble trap.

[0031] The fastener 140 and its associated components assist in supporting and connecting the discharge return tube 66 to the discharge return port 126 via a connector 142 continuously coupled to the connecting tube 144, and also assist in supporting, inserting, and connecting the fluid supply tube 70 to the fluid injection port 122. The fastener 140 may include tabs 141a and 142b that extend outward and are vertically aligned and facing opposite directions from one another. The tabs 141a and 142b prevent the discharge return tube 66 and the fluid supply tube 70, including the fastener 140 and its associated high-pressure fluid supply tube 64, from coming into contact with a roller pump (not explicitly shown) provided in or near the transport assembly 22, which is located in the drive unit 12.

[0032] Figure 3 is a partially exploded side view of the components of Figure 2, illustrating the relationship between the pump 56, the bubble trap 60, the connecting manifold assembly 62, and the fixture 140. A tubular manifold 148, fixed to the bracket 120 and positioned vertically, is also shown. The discharge port 124 may be connected to and fluid-connected to the lower interior of the tubular manifold 148. The discharge return port 126 may be connected to and fluid-connected to the upper interior of the tubular manifold 148. Also connected to the tubular manifold 148 are horizontally aligned insertion ports 150 and associated connectors 132, each facing the discharge return port 126. The insertion port 150 may house a high-pressure fluid supply tube 64. The high-pressure fluid supply tube 64 extends distally through the lumen of the insertion port 150 (not explicitly shown), the connector 132, the upper region of the tubular manifold 148, the drain return port 126, the connector 142, and the connecting tube 144, and enters and extends distally through the drain return tube 66 in a coaxial manner to connect to the thrombectomy catheter 58 (see, for example, Figure 1). The proximal end of the high-pressure fluid supply tube 64 includes a high-pressure fitting 152 located near the proximal end of the high-pressure fluid supply tube 64 to facilitate connection of the high-pressure fluid supply tube 64 to the inside of the pump 56. The proximal end of the high-pressure fluid supply tube 64, which is the inlet to the high-pressure fluid supply tube 64, may include a number of very small holes (not shown) that constitute a filter at its proximal end. The connector 134 may have internal and / or external threads. The connector 134 may be arranged to cover and surround the high-pressure fluid supply tube 64 distal to the high-pressure fitting 152. Alternatively, the connector 134 may be screw-connected to a threaded connection port 154 extending horizontally from the upper member 110 of the base 109 of the pump 56. The connector 134 may be rotated to screw-connect the high-pressure fitting 152 to a corresponding threaded structure provided on the pump 56.Connector 132 may be used to engage the externally threaded end of connector 134 for securing connector 134, and thereby to connect the pump 56 to the connecting manifold assembly 62, and to provide fixation of the bubble trap 60 to the pump 56. Furthermore, direct connection and fluid communication between the pump 56 and the bubble trap 60 may be provided by a horizontally positioned pump fluid injection port 156. The pump fluid injection port 156 engages with a corresponding receptor port 158 ​​and seal 159 located inside one end of the bubble trap 60. A fluid injection port 122 located on the bracket 120 may extend behind the tubular manifold 148 to communicate with the inside of the bubble trap 60 for degassing of a fluid (e.g., saline), thereby making the unpressurized fluid (e.g., saline) available to the pump 56.

[0033] Figure 4 is a perspective view of the upper section 200 of the drive unit 12 with panels 16a-16n and other exterior components removed to expose other components within the drive unit 12. The internal structure of the drive unit 12 may include two or more support structures 202a-b that function as members for mounting various components. A vertically positioned reciprocating linear actuator assembly 204 is shown extending between the intermediate portions of support structures 202a and 202b in the upper region of the drive unit 12. The reciprocating linear actuator assembly 204 may be vertically aligned with the transport assembly 22 for automatic engagement with the pump 56 of the subsequent pump / catheter assembly 14. The pump 56 may be arranged and held within the components of the transport assembly 22 with the linear actuator assembly 204 aligned with a specific region of the transport assembly 22 and the pump 56.

[0034] The reciprocating linear actuator 206 may be fixed to the upper surface of the mounting plate 208. The reciprocating linear actuator 206 may include an actuator shaft 210. The actuator shaft 210 may extend freely through the mounting plate 208 (for example, from the upper surface to the lower surface and further to the underside of the lower surface). Furthermore, a cylindrical pump connector 212 may be fixed to the lower end of the actuator shaft 210. Downward operation of the actuator shaft 210 may cause the pump connector 212 to automatically and securely snap from the top to the pump piston head 116 of the pump 56 for the subsequent reciprocating motion of the pump 56. Disengagement of the pump connector 212 from the pump piston head 116 may occur in accordance with the operation of a release mechanism. The release mechanism may be operated via direct user operation of the release mechanism or by issuing a command through the user interface 32. When the release mechanism is operated, the hook of the pump connector 212 may disengage from the pump piston head 116. Subsequently, the reciprocating linear actuator assembly 204 may move the pump connector 212 axially to allow the pump 56 to be pulled vertically from the transport assembly 22.

[0035] The reciprocating linear actuator assembly 204 may include a stroke length detection assembly 216 configured to determine and / or measure the relative position of the actuator shaft 210. The stroke length detection assembly 216 for detecting the stroke length and / or the actuator position is shown and described in relation to Figures 5-7. Figure 5 is a front view of an exemplary reciprocating linear actuator assembly 204. Figure 6 is an enlarged partial front perspective view of the reciprocating linear actuator assembly 204 with the mounting bracket 222 removed. Figure 7 is an enlarged partial rear perspective view of the reciprocating linear actuator assembly 204. In contrast to a system that uses multiple fixed discrete position sensors to track the position and / or movement of the actuator shaft 210, the stroke length detection assembly 216 may provide real-time monitoring of the position of the actuator shaft 210 in response to various pump stroke lengths. This may provide flexibility to use pump / catheter assemblies 14 with different pump stroke lengths or travel amounts required to meet different procedural requirements using the same drive unit 12. Generally, the stroke length detection assembly 216 may include a magnetic strip 218, a magnetic sensor 220, and a bracket 230.

[0036] The magnetic sensor 220 may be mounted on the printed circuit board 224. The printed circuit board 224 may be mounted inside and / or outside the housing 222 or frame, which is fixed to the mounting plate 208. In some cases, the printed circuit board 224 may be coupled to the housing 222 via one or more fastening members 228a-d. The fastening members 228a-d include, but are not limited to, bolts, screws, set screws, pins, etc. The housing 222 is removed in Figure 6 to illustrate the arrangement of the printed circuit board 224 and the stroke length detection assembly 216 in more detail. In some cases, the magnetic sensor 220 may be soldered to the printed circuit board 224. The magnetic sensor 220 may be, but is not limited to, an integrated circuit such as the AS5311IC manufactured by ams-OSRAM AG (Premstetten, Austria). However, other linear sensors may be used as desired. The magnetic sensor 220 may be a system-on-a-chip (SoC) that includes an integrated Hall element, an analog front-end, and digital signal processing on a single chip. The printed circuit board 224 may also be a custom printed circuit board that includes passive support components and connectors. The magnetic sensor 220 and the printed circuit board 224 together may form a printed circuit assembly 226.

[0037] The magnetic strip 218 may be coupled to the actuator shaft 210 and fixed to a portion of a bracket 230 that is movable with it. The bracket 230 may extend from a first end region 232 adjacent to the printed circuit assembly 226 to a second region 234 located between the actuator shaft 210 and the pump connector 212. The bracket 230 may have an overall L-shaped configuration. The bracket 230 may include a first portion 236 extending approximately parallel to the longitudinal axis 240 of the actuator shaft 210 and a second portion 238 extending approximately perpendicular to the longitudinal axis 240 of the actuator shaft 210. However, the bracket 230 can have different configurations as desired. For example, the second portion 238 may extend at an angle not perpendicular to the longitudinal axis 240 of the actuator shaft 210. The first portion 236 may be positioned laterally spaced from the actuator shaft 210. The second portion 238 of the bracket 230 may be fixed to or coupled to the actuator shaft 210 so that the bracket 230 moves linearly along the longitudinal axis 240 as the actuator shaft 210 moves linearly. For example, the free end 242 of the second portion 238 (for example, the end not coupled to the first portion 236 of the bracket 230) may be coupled to the lead screw piston 244 of the actuator shaft 210 via one or more fixing members 246. The fixing members 246 include, but are not limited to, bolts, screws, set screws, pins, etc. In some cases, the fixing members 246 may be configured to adjust the distance between the magnetic strip 218 and the magnetic sensor 220. For example, the position of the bracket 230 may be adjusted to bring the magnetic strip 218 closer to the magnetic sensor 220, or to move the magnetic strip 218 further away from the magnetic sensor 220. However, this is not required. In some cases, the tolerances of the drive unit 12 and its components may be sufficiently tight, in which case the position of the bracket 230 does not need to be adjusted to position the magnetic strip 218 in the desired position relative to the magnetic sensor 220.The magnetic strip 218 may be positioned within a predetermined distance from the magnetic sensor 220. In some embodiments, the magnetic strip 218 may be positioned at a distance of approximately 0.6 millimeters (mm) or less from the magnetic sensor 220. However, in some embodiments, the distance may be greater than 0.6 mm. The fixing member 246 may be fixed or tightened to ensure that the distance between the magnetic strip 218 and the magnetic sensor 220 is fixed or locked after the distance between the magnetic strip 218 and the magnetic sensor 220 has been adjusted (if adjustable).

[0038] The first end region 232 of the bracket 230 may extend through the opening 268 in the mounting plate 208 so that it is adjacent to the magnetic sensor 220 when the actuator shaft 210 is at the lower end of its stroke, as shown in Figures 5-7. When the actuator shaft 210 moves upward, the bracket 230 moves with the actuator shaft 210. Figure 8 is an enlarged front perspective view of the reciprocating linear actuator assembly 204 with the mounting bracket 222 removed and the actuator shaft 210 moved or raised in the axial direction. As can be seen in Figure 8, when the actuator shaft 210 is raised, the first end region 232 of the bracket 230 also moves upward. When the bracket 230 moves, the magnetic strip 218 also moves.

[0039] The magnetic strip 218 may be fixed to the surface of the first portion 236 of the bracket 230. For example, the magnetic strip 218 may be fixed to the surface of the first portion 236 facing the magnetic sensor 220. For example, the magnetic strip 218 may be positioned between the first portion of the bracket 230 and the magnetic sensor 220. In the illustrated embodiment, the magnetic strip 218 is mounted on a surface facing away from the actuator shaft 210. However, this is not mandatory. The placement of the magnetic strip 218 may depend on the position of the magnetic sensor 220. The magnetic strip 218 may be fixed to the bracket 230, for example, using an adhesive strip. However, other methods may be used to fix the magnetic strip 218 to the bracket 230 as desired. The magnetic strip 218 may have a total length extending from the first end 217 to the second end 219. Furthermore, the magnetic strip 218 may have a width substantially equal to or smaller than the width W of the first portion 236 of the bracket 230. In some cases, the magnetic strip 218 may extend along the entire length of the first portion 236 of the bracket 230. In other embodiments, the magnetic strip 218 may extend along a shorter range than the entire length of the first portion 236 of the bracket 230. The magnetic strip 218 may have a length that allows it to be adjacent to the magnetic sensor 220 over the entire stroke length of the actuator shaft 210. For example, the magnetic strip 218 may have a length that is substantially equal to or greater than the stroke length of the actuator shaft 210.

[0040] Figure 9 shows a front view of a portion of a magnetic strip 218 adjacent to a magnetic sensor 220 and the electrical outputs or signals from multiple magnetic sensors 220. The magnetic strip 218 may include multiple pairs 248 of north poles and south poles. The portion of the magnetic strip 218 shown in Figure 9 is not necessarily to scale. Furthermore, for the sake of brevity and ease of understanding, each pair 248 of north poles and south poles is not indicated by a reference number. Each of the multiple pairs 248 of north poles and south poles may include a north pole 250 and a south pole 252 extending in the width direction of the magnetic strip 218. The multiple pairs 248 of north poles and south poles may be repeated continuously along the entire length of the magnetic strip 218 (for example, from the first end 217 to the second end 219). Each pair 248 of north poles and south poles may have a length of approximately 2 millimeters (mm), such that each pole 250, 252 has a length of approximately 1 mm. However, each pair of north and south poles 248 may have a length 254 smaller than 2 mm or larger than 2 mm, as desired.

[0041] As described above, the magnetic strip 218 is positioned on the bracket 230 so that, as the actuator shaft 210 reciprocates to operate the pump 58, the magnetic strip 218 moves vertically (for example, parallel to the longitudinal axis 240 of the actuator shaft 210) upward and downward adjacent to the magnetic sensor 220. The direction of movement of the magnetic strip 218 is illustrated by arrow 256. When the magnetic strip 218 and magnetic sensor 220 are assembled into the drive unit 12, the direction of movement of the magnetic strip 218, indicated by arrow 256, is parallel to the longitudinal axis 240 of the actuator shaft 210. Because the bracket 230 is coupled to the lead screw piston 244 of the actuator shaft 210, the magnetic strip 218 moves in direct proportion to the distance traveled by the actuator shaft 210. When the magnetic strip 218 moves (illustrated by arrow 256), the magnetic sensor 220 may output multiple data outputs or signals regarding the position of the magnetic strip 218. For example, the magnetic sensor 220 may output an absolute output 258 that includes a count from 0 to a predetermined maximum value N for each pair of N and S poles 248, and repeats for each pair of N and S poles 248. For example, the count starts from 0 for each new pair of N and S poles 248. In some cases, the predetermined maximum count value of the absolute output may be 4095, however this is not required. The predetermined maximum value may be determined by the type of magnetic sensor 220 and / or the length 254 of the pairs of N and S poles 248. The absolute output can be considered to provide an index of the position of the magnetic strip 218 within a particular pair of N and S poles 248. The magnetic sensor 220 may also output a pulse-width modulation (PWM) output 260. PWM may start with an initial pulse width (measured in microseconds (μs)) and increase with each step (a step of a predetermined distance) so that the PMS reaches a maximum pulse width X at the end of the pair of north and south poles.In some cases, the pulse width may increase in steps of 0.488 micrometers (μm), and may reach a maximum pulse width of 4097 μs at the end of 248 pairs of north and south poles. An index pulse 262 may be generated once for each of 248 pairs of north and south poles. Finally, the magnetic sensor 220 may also include A output 264 and B output 266. The A output 264 and B output 266 may be phase-shifted by approximately 90 electric degrees. Thus, the number of edges of the A output 264 and B output 266 may be the number of incremental pulses Y per 248 pairs of north and south poles multiplied by 4 (for example, each of the A output 264 and B output 266 may include a rising edge and a falling edge for each incremental pulse). In an exemplary embodiment, 256 incremental pulses may be generated for each of the A output 264 and B output 266 per 248 pairs of north and south poles. Therefore, a system having 256 incremental pulses may include 1024 edges for every 248 pairs of north and south poles. When the magnetic strip 218 is actuated adjacent to the magnetic sensor 220, the incremental pulses may be repeated for every 248 pairs of north and south poles. Each incremental pulse may represent an incremental distance traveled by the magnetic strip 218 (and thus the actuator shaft 210). In some cases, each incremental pulse may correlate to a distance in the micrometer range. It is thought that which of the A output 264 and B output 266 represents the rising edge and which represents the falling edge of each incremental pulse may depend on the direction of movement of the magnetic strip 218.

[0042] Figure 10 is a schematic graph 300 showing the A output 264 and B output 266 of the incremental pulse as the magnetic strip 218 moves relative to the magnetic sensor 220. Generally, the field-programmable gate array (FPGA) logic in the system-on-chip (e.g., the magnetic sensor 220) may read the states of the A output 264 and B output 266 of the incremental pulse. If the A output 264 rises from 0 to 1 while the B output 266 is 0, the actuator shaft 210 continues to move incrementally in one direction. Conversely, if the B output 266 rises while the A output 264 is 0, the actuator shaft 210 continues to move in the opposite direction. The A output 264 and B output 266 of the incremental pulse may rise and fall together with each incremental step of the linear encoder. The FPGA may maintain a cumulative count of each rising edge, and this count may be added or subtracted depending on whether the A output 264 or the B output 266 of the incremental pulse rises first. This count may then correspond to the position of the actuator shaft 210, because the FPGA can track the actuator shaft 210 from the time the count is "zeroed out" by the firmware. Thus, this may be a relative measurement of the actuator's movement. The FPGA may also check upper or lower limits of movement of the actuator shaft 210 as defined by the firmware, and the FPGA may flag or identify when the actuator shaft 210 moves outside those limits. In some cases, a warning may be displayed on the user interface when the actuator shaft 210 moves outside the predetermined upper and / or lower limits. The upper and / or lower limits may be dynamically defined by the firmware through FPGA registers and may be changed or adjusted. The magnetic sensor 220 may communicate with the user interface 32 to allow the user to view information regarding the position and / or stroke length of the actuator shaft 210.

[0043] The mechanical zero point position is indicated by 302. The mechanical zero point position 302 may be generated by zero-setting the reading position of the magnetic sensor in software. In some cases, the zero-setting step may be performed in the user interface 32. The mechanical zero point position 302 does not necessarily have to be the same each time the drive unit 12 is used. The mechanical zero point position 302 may exist in any configuration of the reciprocating linear actuator assembly 204 at the time of zero-setting. For example, the stroke length detection assembly 216 may be at the lowest position, the highest position, or a position between the lowest and highest positions at the time of zero-setting. The A output 264 and B output 266 of the incremental pulse may be relative to the mechanical zero point position 302 and may not be absolute values ​​corresponding to a specific point on the magnetic strip 218. Any movement of the actuator shaft 210 (and therefore the magnetic strip 218) after the mechanical zero point position 302 has been determined is measured and processed by the magnetic sensor 220. This data may be output to the user interface 32.

[0044] Graph 300 illustrates the index count 318. As described above, the index count may represent each pair of N and S poles (248). The first section 304 of graph 300 may show the A output 264 and B output 266 of the incremental pulse as the magnetic strip 218 moves from top to bottom. The second section 308 of graph 300 may show the A output 264 and B output 266 of the incremental pulse as the magnetic strip 218 moves from bottom to top. For simplicity and ease of understanding, the illustrated graph 300 may not illustrate each incremental pulse for each pair of N and S poles (248). Changes in the direction of movement of the magnetic strip 218 are shown in 306. When the magnetic strip 218 moves from top to bottom, the A output 264 of the incremental pulse may precede or occur before the B output 266 of the incremental pulse. For example, when the magnetic strip 218 moves from top to bottom, the rising edge 310 of the A output 264 of the incremental pulse occurs approximately 90 electric degrees before the rising edge 312 of the B output 266 of the incremental pulse. When the magnetic strip 218 moves from bottom to top, the B output 266 of the incremental pulse may precede or occur before the A output 264 of the incremental pulse. For example, when the magnetic strip 218 moves from bottom to top, the rising edge 314 of the B output 266 of the incremental pulse occurs approximately 90 electric degrees before the rising edge 316 of the A output 264 of the incremental pulse. Therefore, the magnetic sensor 220 may determine the direction of movement of the magnetic strip 218 (and thus the actuator shaft 210) based on whether the A output 264 or the B output 266 of the incremental pulse is output first. In the embodiment shown in Figure 10, the magnetic strip 218 moves from top to bottom for a certain period of time, as shown at 304. As the magnetic strip 218 moves, it passes over the mechanical zero point position 302. At 306, the direction of movement of the magnetic strip 218 is reversed, causing the magnetic strip 218 to move from bottom to top. It passes over the mechanical zero point position 302 once again.As shown in Figure 10, the same number of pulses are generated between the mechanical zero point position 302 and the direction reversal position 306, regardless of the direction of movement.

[0045] The magnetic sensor 220 may further count the number of incremental pulse outputs to determine the distance traveled. For example, each incremental pulse output may correspond to an incremental movement of the magnetic strip 218 (for example, the incremental movement may be in the range of micrometers). The magnetic sensor 220 may add counts when the magnetic strip 218 moves in a first direction and subtract counts when the magnetic strip 218 moves in a second direction opposite to the first direction to measure the relative position from the mechanical zero point position 302. Furthermore, the distance traveled may be used to measure the speed of movement of the actuator shaft 210. In some cases, the actuator shaft 210 may have a downward speed in the range of approximately 6.72 inches per second (17.07 centimeters per second) and an upward speed in the range of approximately 12 inches per second (30.5 centimeters per second). The measured distance traveled and speed may be used to verify proper operation of the distance traveled and speed.

[0046] The materials available for various components of the thrombectomy catheters, pump / catheter assemblies, and / or other devices disclosed herein may include those generally associated with medical devices. For simplicity, the following discussion will refer to pump / catheter assemblies and their associated components. However, this is not intended to be limited to the devices and methods described herein. The following discussion may also apply to other similar devices, tubular members, and / or components of tubular members or devices disclosed herein.

[0047] Various components of the devices / systems disclosed herein may include metals, alloys, polymers (multiple examples disclosed herein), metal-polymer composites, ceramics, combinations thereof, and similar or other suitable materials. Multiple examples of suitable metals and alloys include stainless steel such as 304V, 304L, and 316LV stainless steels, mild steel, nickel-titanium alloys such as linear elastic and / or superelastic Nitinol, other nickel alloys such as nickel-chromium-molybdenum alloys (e.g., UNS:N06625 such as INCONEL® 625, UNS:N06022 such as HASTELLOY® C-22®, UNS:N10276 such as HASTELLOY® C276®, and other HASTELLOY® alloys), nickel-copper alloys (e.g., UNS:N04400 such as MONEL® 400, NICKELVAC® 400, NICORROS® 400), and This may include nickel-cobalt-chromium-molybdenum alloys (e.g., UNS:R30035 such as MP35-N®), nickel-molybdenum alloys (e.g., UNS:N10665 such as HASTELLOY® ALLOYB2®), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten alloys, or tungsten alloys, as well as cobalt-chromium alloys, cobalt-chromium-molybdenum alloys (e.g., UNS:R30003 such as ELGILOY® PHYNOX®), platinum-enriched stainless steel, titanium, combinations thereof, and other similar or suitable materials.

[0048] Several examples of suitable polymers include polytetrafluoroethylene (PTFE), ethylenetetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, e.g., DELRIN® from DuPont), polyether block esters, polyurethane (e.g., polyurethane 85A), polypropylene (PP), polyvinyl chloride (PVC), polyether esters (e.g., ARNITEL® from DSM Engineering Plastics), ether or ether-based copolymers (e.g., butylene / poly(alkylene ether) phthalate and / or other polyester elastomers such as HYTREL® from DuPont), polyamides (e.g., DURETHAN® from Bayer or CRISTAMID® from ElfAtochem), elastic polyamides, block polyamides / ethers, polyether block amides (PEBA,For example, available under the trademark PEBAX®), ethylene vinyl acetate copolymer, silicon, polyethylene (PE), MARLEX® high-density polyethylene, MARLEX® low-density polyethylene, linear low-density polyethylene (for example, REXELL®), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyether ether ketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly-p-phenylene terephthalamide (for example, KEVLAR®), polysulfone, nylon, nylon-12 (for example, EMSAmerican) The material may include GRILAMID® (manufactured by Grilon), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefins, polystyrene, epoxy, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (e.g., SIBS and / or SIBSA), polycarbonate, ionomer, biocompatible polymer, other suitable materials, or mixtures, combinations, copolymers, polymer / metal composites thereof. In some embodiments, the sheath may be blended with liquid crystal polymer (LCP). For example, the mixture may contain up to about 6% LCP.

[0049] In at least some embodiments, some or all of the pump / catheter assembly and its associated components may be doped with, formed from, or otherwise incorporate radiopaque material. Radiopaque material is understood to be a material that can produce a relatively bright image on a fluoroscopy screen or other imaging technique during a medical procedure. This relatively bright image assists the user of the pump / catheter assembly and its associated components in locating them. Examples of radiopaque materials may include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloys, and polymer materials filled with radiopaque fillers. Furthermore, other radiopaque marker bands and / or coils may be incorporated into the design of the pump / catheter assembly and its associated components to achieve the same effect.

[0050] It should be understood that this disclosure is merely illustrative in many respects. In particular, details relating to shape, dimensions, and process arrangement may be modified without departing from the scope of this disclosure. This may include, to the appropriate extent, using features of any of the exemplary embodiments in other embodiments. The scope of this disclosure is, of course, defined by the language expressed in the appended claims.

Claims

1. A drive unit for a thrombectomy system, One or more panels enclosing the internal structure of the drive unit, A reciprocating linear actuator assembly positioned vertically in the upper region of the drive unit, extending between at least one support structure, comprising a reciprocating linear actuator assembly including an actuator shaft, A bracket coupled to the actuator shaft and movable together with the actuator shaft, the bracket including a first portion extending parallel to the longitudinal axis of the actuator shaft, A magnetic strip fixed to the surface of the first portion of the bracket, The bracket comprises a magnetic sensor positioned adjacent to the first end region of the bracket, The magnetic sensor is configured to measure the relative position of the actuator shaft. Drive unit.

2. The magnetic sensor is fixed within a housing that is fixed to the upper surface of the mounting plate. The drive unit according to claim 1.

3. The magnetic sensor is mounted on a printed circuit board. The drive unit according to claim 1 or 2.

4. The first portion of the bracket is configured to extend through the opening in the mounting plate. The drive unit according to any one of claims 1 to 3.

5. The magnetic strip is positioned between the bracket and the magnetic sensor. The drive unit according to any one of claims 1 to 4.

6. The magnetic strip includes multiple pairs of north poles and south poles. The drive unit according to any one of claims 1 to 5.

7. The plurality of pairs of N poles and S poles extend along the entire length of the magnetic strip. The drive unit according to claim 6.

8. The magnetic sensor includes a system-on-a-chip, The drive unit according to any one of claims 1 to 7.

9. The magnetic sensor is configured to output signal A and signal B. The drive unit according to any one of claims 1 to 8.

10. If the A signal rises from 0 to 1 while the B signal is 0, the actuator shaft moves in the first direction. The drive unit according to claim 9.

11. If signal B rises from 0 to 1 while signal A is 0, the actuator shaft moves in a second direction opposite to the first direction. The drive unit according to claim 10.

12. When the actuator shaft moves in the first direction, the magnetic sensor adds to the count of rising edges, and when the actuator shaft moves in the second direction, the magnetic sensor subtracts from the count of rising edges. The drive unit according to claim 11.

13. The count of the rising edge is directly correlated with the distance traveled by the actuator shaft. The drive unit according to claim 12.

14. The magnetic strip has an overall length substantially equal to or greater than the stroke length of the actuator shaft. The drive unit according to any one of claims 1 to 13.

15. The magnetic strip moves linearly in direct proportion to the linear movement of the actuator shaft. The drive unit according to any one of claims 1 to 14.

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