Patent Publication Number: US-2022226570-A1

Title: Infusion pump control unit keypad

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This Application claims the benefit of U.S. Provisional Patent Application No. 63/140,137 entitled “INFUSION PUMP CONTROL UNIT KEYPAD,” filed on Jan. 21, 2021, the disclosure of which is hereby incorporated by reference in its entirety for all purposes. 
    
    
     TECHNICAL FIELD 
     The present disclosure generally relates to infusion pumps, in particular infusion pump control unit keypads with fluid ingress protection. 
     BACKGROUND 
     In typical infusion pump design, a pump control unit has a keypad for entry of information and control of pump settings by a user. The typical pump control unit keypad has multiple layers of components such as overlays, protective liners, circuit layers, etc., all stacked together like a sandwich. However, the typical combination of components provides seams or gaps that can allow fluid ingress. As infusion pumps are consistently used in medical settings, such as operating rooms and hospital rooms, these infusion pumps are routinely cleaned with liquids. Accordingly, the typical pump control unit keypad suffers from fluid ingress into the internal components, resulting in corrosion and damage to metal components, electronic components and flex cables. This results in costly repairs and replacements of infusion pump components. 
     For these reasons, it is desirable to provide pump control unit keypads that prevent fluid ingress under standard operating conditions, thus improving the life cycle and reliability of infusion pumps while reducing repair costs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the principles of the disclosure. 
         FIG. 1  depicts a perspective view of an example patient care system having a pump control unit and four fluid infusion pumps, each of which is connected to a respective fluid supply for pumping the contents of the fluid supply to a patient, according to some aspects of the disclosure. 
         FIG. 2  depicts a front view of an internal pump control unit keypad component showing corrosion damage from fluid ingress. 
         FIG. 3  depicts a rear view of an internal pump control unit keypad cable showing corrosion damage from fluid ingress. 
         FIG. 4  depicts a front view of a portion of a typical pump control unit keypad without a top overlay, according to aspects of the disclosure. 
         FIG. 5  depicts a front view of a pump control unit keypad without a top overlay, according to aspects of the disclosure. 
         FIG. 6  depicts a front view of a pump control unit keypad front cover and gasket assembly, according to aspects of the disclosure. 
         FIG. 7  depicts an exploded perspective view of a pump control unit keypad assembly, according to aspects of the disclosure. 
         FIG. 8  depicts a front view of a pump control unit keypad overlay, according to aspects of the disclosure. 
         FIG. 9  illustrates a method of making a pump control unit keypad assembly, according to aspects of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description set forth below describes various configurations of the subject technology and is not intended to represent the only configurations in which the subject technology may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the subject technology. Accordingly, dimensions are provided in regard to certain aspects as non-limiting examples. However, it will be apparent to those skilled in the art that the subject technology may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form in order to avoid obscuring the concepts of the subject technology. 
     It is to be understood that the present disclosure includes examples of the subject technology and does not limit the scope of the appended claims. Various aspects of the subject technology will now be disclosed according to particular but non-limiting examples. Various embodiments described in the present disclosure may be carried out in different ways and variations, and in accordance with a desired application or implementation. 
     Referring now in more detail to the drawings in which like reference numerals refer to like or corresponding elements among the several views, there is shown in  FIG. 1  a patient care system  20  having four infusion pumps  22 ,  24 ,  26 , and  28  each of which is fluidly connected with an upstream fluid line  30 ,  32 ,  34 , and  36 , respectively. Each of the four infusion pumps  22 ,  24 ,  26 , and  28  is also fluidly connected with a downstream fluid line  31 ,  33 ,  35 , and  37 , respectively. The fluid lines can be any type of fluid conduit, such as an IV administration set, through which fluid can flow through. It should be appreciated that any of a variety of pump mechanisms can be used including syringe pumps. 
     Fluid supplies  38 ,  40 ,  42 , and  44 , which may take various forms but in this case are shown as bottles, are inverted and suspended above the pumps. Fluid supplies may also take the form of bags or other types of containers including syringes. Both the patient care system  20  and the fluid supplies  38 ,  40 ,  42 , and  44  are mounted to a roller stand, IV pole  46 , table top, etc. 
     A separate infusion pump  22 ,  24 ,  26 , and  28  is used to infuse each of the fluids of the fluid supplies into the patient. The infusion pumps are flow control devices that will act on the respective fluid line to move the fluid from the fluid supply through the fluid line to the patient  48 . Because individual pumps are used, each can be individually set to the pumping or operating parameters required for infusing the particular medical fluid from the respective fluid supply into the patient at the particular rate prescribed for that fluid by the physician. Such medical fluids may include drugs or nutrients or other fluids. The infusion pumps  22 ,  24 ,  26 , and  28  are controlled by a pump control unit  60 . 
     Fluid supplies  38 ,  40 ,  42 , and  44  are each coupled to an electronic data tag  81 ,  83 ,  85 , and  87 , respectively, or to an electronic transmitter. Any device or component associated with the infusion system may be equipped with an electronic data tag, reader, or transmitter. 
     Typically, medical fluid administration sets have more parts than are shown in  FIG. 1 . Many have check valves, drip chambers, valves with injection ports, connectors, and other devices well known to those skilled in the art. These other devices have not been included in the drawings so as to preserve clarity of illustration. 
     Turning now to  FIGS. 2-4 , a typical pump control unit keypad  100  includes fillers  110  that are used to ensure that a keypad overlay (not shown) fits over the internal keypad assembly  120  without damage to either the keypad overlay or the internal keypad assembly  120 . The use of the fillers  110  typically results in seams and/or gaps between the keypad overlay and the internal keypad assembly  120 , thus allowing for fluid ingress into the pump control unit keypad  100 . For example, as shown in  FIG. 2 , a component layer  130  (e.g., electrostatic discharge (ESD) shield) has corrosion damage  135  due to fluid ingress into the pump control unit keypad  100 . As another example, as shown in  FIG. 3 , an internal cable  140  (e.g., flex tail cable) also has corrosion damage  145  due to fluid ingress into the pump control unit keypad  100 . Such corrosion damage typically will cause the internal keypad assembly  120  to fail, requiring repair or replacement of the pump control unit keypad  100 . 
     Turning now to  FIGS. 5-8 , pump control unit keypad assembly  200  is shown according to aspects of the disclosure. As shown in  FIGS. 6 , pump control unit keypad assembly  200  includes a gasket  205  (e.g., full perimeter gasket) disposed on a front cover assembly  210 . Here, the gasket  205  provides a full perimeter seal against an overlay  215  (see  FIG. 8 ) when the overlay  215  is coupled to the front cover assembly  210  and gasket  205 . The gasket  205  eliminates the need for fillers  110  as the gasket  205  itself provides a seat for the overlay  215  that keeps the overlay  215  from damaging, cracking or crushing the remaining components of the pump control unit keypad assembly  200 . Further, since the gasket  205  provides a full perimeter seal against the overlay  215 , there are no seams of gaps that allow for fluid ingress into the pump control unit keypad assembly  200 . Thus, the pump control unit keypad assembly  200  may be freely sprayed and/or cleaned with liquids without incurring the corrosion issues discussed above. 
     As shown in  FIG. 7 , the pump control unit keypad assembly  200  includes many components that are stacked or sandwiched together to form the complete assembly  200 . A rear protective liner  220  may be disposed on the back or internal side of the front cover assembly  210 , the rear protective liner  220  disposed within or covering a window  216  in the front cover assembly  210 . The gasket  205  is disposed on the front or external facing side  211  of the front cover assembly  210 , inside a raised perimeter  218  of the front cover assembly  210 . Stacked upward or outward from the front cover assembly  210  are a lens  222 , an adhesive layer  224  (e.g., optically clear adhesive), a rear adhesive  226 , a metal layer  228  (e.g., Mylar™), a printed circuit board (PCB) connector  230 , a polycap  232 , a circuit layer  234 , multiple semiconductor switch domes  236 , a dome spacer  238 , a dome overlay  240 , a shielding adhesive  242 , an ESD shield  244  with a tail stiffener  246 , a light source adhesive  248 , a light source  250  (e.g., fiber optic lamp), a light block  252 , an overlay adhesive  254 , the overlay  215  and a protective liner  256 . 
     The stack of components from the lens  222  to the light block  252  are sized and shaped to fit within an inner perimeter  207  of the gasket  205 , for a portion of the component (e.g., a tail of the circuit layer  234 , tail of the ESD shield  244 , tail of the light source  250 ) to extend past an outer perimeter  209  of the gasket  205  through openings  212 ,  214  on the front cover assembly  210 , or for a portion of the component (e.g., a tail of the circuit layer  234  or the ESD shield  244 ) to extend past an outer perimeter  209  of the gasket  205  between the gasket  205  and the front cover assembly  210 . No portion of any of the components of the pump control unit keypad assembly  200  extends over the outer surface  203  of the gasket  205 , and thus no portion of any of the components of the pump control unit keypad assembly  200  come between the outer surface  203  of the gasket  205  and the overlay  215 . The result is a liquid proof or resistant seal between the outer surface  203  of the gasket  205  and the overlay  215  around the entire perimeter of the gasket  205 . 
     In some aspects of the disclosure, a membrane switch may be used in place of any combination of the above described components. In some aspects of the disclosure, the gasket  205  may have a height that equals or exceeds the combined height of the outer perimeter of the stack of components from the lens  222  to the light source  250  or the light block  252 . In aspects of the disclosure, the pump control unit keypad assembly  200  is configured to provide venting (e.g., via vent holes), to work for 200,000 keypresses, to operate in a temperature range of 41-104 degrees Fahrenheit, as well as to withstand storage temperature, humidity and pressure. 
     In aspects of the disclosure, the light source  250  may have asymmetrical panels where a wider panel may be used to provide increased illumination over a narrower panel. In aspects of the disclosure, the gasket  205  may be formed of any suitable material (e.g., rubber, silicone). 
     According to some aspects of the disclosure, a method  300  of making a pump control unit keypad assembly  200  is shown in  FIG. 9 . In step  310 , a protective liner (e.g., rear protective liner  220 ) is placed on a back surface of a cover assembly (e.g., front cover assembly  210 ). A gasket (e.g., gasket  205 ) is placed on the cover assembly (e.g., within a raised perimeter of front cover assembly  210 ), in step  320 . In step  330 , a lens having an adhesive (e.g., lens  222  and optically clear adhesive layer  224 ) is coupled to the cover assembly. An adhesive (e.g., rear adhesive  226 ) is coupled to the cover assembly, in step  340 . 
     In step  350 , a circuit assembly (e.g., metal layer  228 , PCB connector  230 , polycap  232 , circuit layer  234 ) are coupled to the adhesive. Here, a portion of the circuit assembly (e.g., tail of circuit layer  234 ) may be fed or poked through a cover assembly opening (e.g., opening  212 ). A switch assembly (e.g., semiconductor switch domes  236 , dome spacer  238 , dome coverlay  240 ) are placed on the circuit components, in step  360 . In step  370 , a shield assembly (e.g., shielding adhesive  242 , ESD shield  244 , tail stiffener  246 ) are coupled to the switch assembly. Here, a portion of the shield assembly (e.g., tail of ESD shield  244 ) may be fed or poked through a cover assembly opening (e.g., opening  212 ). 
     A light assembly (e.g., light source adhesive  248 , light source  250 , light block  252 ) are coupled to the shield assembly, in step  380 . Here, a portion of the light assembly (e.g., tail of light source  250 ) may be fed or poked through a cover assembly opening (e.g., opening  214 ). In step  390 , an overlay assembly (e.g., overlay adhesive  254 , overlay  215 , protective liner  256 ) is coupled to the light assembly. 
     In some embodiments, an infusion pump control unit keypad assembly comprises a cover assembly having an outer surface and an inner surface; a perimeter gasket disposed within a raised perimeter on the outer surface of the cover assembly; a lens coupled to the outer surface of the cover assembly; a circuit assembly coupled to outer surface of the cover assembly; a switch assembly coupled to the circuit assembly; a shield assembly coupled to the switch assembly; a light assembly coupled to the shield assembly; and an overlay assembly coupled to the light assembly. 
     In aspects of the disclosure, a protective liner is coupled to one of the inner surface of the cover assembly and the lens. In aspects of the disclosure, an optically clear adhesive is coupled to the lens. In aspects of the disclosure, the circuit assembly comprises: a metal layer; a printed circuit board connector; a polycap; and a circuit layer. In aspects of the disclosure, the circuit assembly is coupled to the cover assembly by an adhesive layer. In aspects of the disclosure, the switch assembly comprises: a plurality of semiconductor switch domes; a dome spacer; and a dome coverlay. In aspects of the disclosure, the switch assembly comprises a membrane switch. In aspects of the disclosure, the shield assembly comprises: an electrostatic shield; and a tail stiffener. 
     In aspects of the disclosure, the shield assembly is coupled to the switch assembly by an adhesive layer. In aspects of the disclosure, the light assembly comprises: a fiber optic lamp; and a light block layer. In aspects of the disclosure, the light assembly is coupled to the shield assembly by an adhesive layer. In aspects of the disclosure, the overlay assembly comprises: an overlay; and a protective liner. In aspects of the disclosure, the overlay assembly is coupled to the light assembly by an adhesive layer. In aspects of the disclosure, a tail portion of the circuit assembly and a tail portion of the shield assembly are disposed through an opening in the cover assembly past the inner surface of the cover assembly. In aspects of the disclosure, a tail portion of the light assembly is disposed through an opening in the cover assembly past the inner surface of the cover assembly. 
     In some embodiments, a method of making an infusion pump control unit keypad assembly comprises: placing a gasket within a raised perimeter of an outer surface of a cover assembly; coupling a lens and an optically clear adhesive to a window of the cover assembly; coupling a circuit assembly to the outer surface of the cover assembly with a rear adhesive layer; coupling a switch assembly to the circuit assembly; coupling a shield assembly to the switch assembly with a shielding adhesive layer; coupling a light assembly to the shield assembly with a light source adhesive layer; and coupling an overlay assembly to the light assembly with an overlay adhesive layer. 
     In aspects of the disclosure, the method comprises coupling a protective lining to one of the lens and an inner surface of the cover assembly over the window. In aspects of the disclosure, the method comprises feeding a tail section of the circuit assembly and a tail section of the shield assembly from the outer surface of the cover assembly through an opening in the cover assembly and past an inner surface of the cover assembly. In aspects of the disclosure, the method comprises feeding a tail section of the light assembly from the outer surface of the cover assembly through an opening in the cover assembly and past an inner surface of the cover assembly. In aspects of the disclosure, the method comprises engaging an outer surface of an entire perimeter of the gasket to an inner surface of the overlay assembly to provide a fluid tight fit against fluid ingress from external fluid sources. 
     It is understood that any specific order or hierarchy of blocks in the methods of processes disclosed is an illustration of example approaches. Based upon design or implementation preferences, it is understood that the specific order or hierarchy of blocks in the processes may be rearranged, or that all illustrated blocks be performed. In some implementations, any of the blocks may be performed simultaneously. 
     The present disclosure is provided to enable any person skilled in the art to practice the various aspects described herein. The disclosure provides various examples of the subject technology, and the subject technology is not limited to these examples. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. 
     A reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” Unless specifically stated otherwise, the term “some” refers to one or more. Pronouns in the masculine (e.g., his) include the feminine and neuter gender (e.g., her and its) and vice versa. Headings and subheadings, if any, are used for convenience only and do not limit the invention. 
     The word “exemplary” is used herein to mean “serving as an example or illustration.” Any aspect or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs. In one aspect, various alternative configurations and operations described herein may be considered to be at least equivalent. 
     As used herein, the phrase “at least one of” preceding a series of items, with the term “or” to separate any of the items, modifies the list as a whole, rather than each item of the list. The phrase “at least one of” does not require selection of at least one item; rather, the phrase allows a meaning that includes at least one of any one of the items, and/or at least one of any combination of the items, and/or at least one of each of the items. By way of example, the phrase “at least one of A, B, or C” may refer to: only A, only B, or only C; or any combination of A, B, and C. 
     A phrase such as an “aspect” does not imply that such aspect is essential to the subject technology or that such aspect applies to all configurations of the subject technology. A disclosure relating to an aspect may apply to all configurations, or one or more configurations. An aspect may provide one or more examples. A phrase such as an aspect may refer to one or more aspects and vice versa. A phrase such as an “embodiment” does not imply that such embodiment is essential to the subject technology or that such embodiment applies to all configurations of the subject technology. A disclosure relating to an embodiment may apply to all embodiments, or one or more embodiments. An embodiment may provide one or more examples. A phrase such an embodiment may refer to one or more embodiments and vice versa. A phrase such as a “configuration” does not imply that such configuration is essential to the subject technology or that such configuration applies to all configurations of the subject technology. A disclosure relating to a configuration may apply to all configurations, or one or more configurations. A configuration may provide one or more examples. A phrase such a configuration may refer to one or more configurations and vice versa. 
     As used herein, the terms “determine” or “determining” encompass a wide variety of actions. For example, “determining” may include calculating, computing, processing, deriving, generating, obtaining, looking up (e.g., looking up in a table, a database or another data structure), ascertaining and the like via a hardware element without user intervention. Also, “determining” may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory) and the like via a hardware element without user intervention. “Determining” may include resolving, selecting, choosing, establishing, and the like via a hardware element without user intervention. 
     As used herein, the terms “provide” or “providing” encompass a wide variety of actions. For example, “providing” may include storing a value in a location of a storage device for subsequent retrieval, transmitting a value directly to the recipient via at least one wired or wireless communication medium, transmitting or storing a reference to a value, and the like. “Providing” may also include encoding, decoding, encrypting, decrypting, validating, verifying, inserting and the like via a hardware element. 
     As used herein, the term “message” encompasses a wide variety of formats for communicating (e.g., transmitting or receiving) information. A message may include a machine readable aggregation of information such as an XML, document, fixed field message, comma separated message, or the like. A message may, in some implementations, include a signal utilized to transmit one or more representations of the information. While recited in the singular, it will be understood that a message may be composed, transmitted, stored, received, etc. in multiple parts. 
     In one aspect, unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. In one aspect, they are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain. 
     It is understood that the specific order or hierarchy of steps, operations or processes disclosed is an illustration of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps, operations or processes may be rearranged. Some of the steps, operations or processes may be performed simultaneously. Some or all of the steps, operations, or processes may be performed automatically, without the intervention of a user. The accompanying method claims, if any, present elements of the various steps, operations or processes in a sample order, and are not meant to be limited to the specific order or hierarchy presented. 
     All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. § 112 (f) unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for.” Furthermore, to the extent that the term “include,” “have,” or the like is used, such term is intended to be inclusive in a manner similar to the term “comprise” as “comprise” is interpreted when employed as a transitional word in a claim. 
     In any embodiment, data can be forwarded to a “remote” device or location,” where “remote,” means a location or device other than the location or device at which the program is executed. For example, a remote location could be another location (e.g., office, lab, etc.) in the same city, another location in a different city, another location in a different state, another location in a different country, etc. As such, when one item is indicated as being “remote” from another, what is meant is that the two items can be in the same room but separated, or at least in different rooms or different buildings, and can be at least one mile, ten miles, or at least one hundred miles apart. “Communicating” information references transmitting the data representing that information as electrical signals over a suitable communication channel (e.g., a private or public network). “Forwarding” an item refers to any means of getting that item from one location to the next, whether by physically transporting that item or otherwise (where that is possible) and includes, at least in the case of data, physically transporting a medium carrying the data or communicating the data. Examples of communicating media include radio or infra-red transmission channels as well as a network connection to another computer or networked device, and the internet or including email transmissions and information recorded on websites and the like. 
     Some embodiments include implementation on a single computer, or across a network of computers, or across networks of networks of computers, for example, across a network cloud, across a local area network, on hand-held computer devices, etc. The computers may be physical machines or virtual machines hosted by other computers. In certain embodiments, one or more of the steps described herein are implemented on a computer program(s). Such computer programs execute one or more of the steps described herein. In some embodiments, implementations of the subject method include various data structures, categories, and modifiers described herein, encoded on computer-readable medium(s) and transmissible over communications network(s). 
     Software, web, internet, cloud, or other storage and computer network implementations of the present invention could be accomplished with standardized programming techniques specifically adapted to cause one or more device to perform the various assigning, calculating, identifying, scoring, accessing, generating or discarding steps described. 
     The Title, Background, Summary, Brief Description of the Drawings and Abstract of the disclosure are hereby incorporated into the disclosure and are provided as illustrative examples of the disclosure, not as restrictive descriptions. It is submitted with the understanding that they will not be used to limit the scope or meaning of the claims. In addition, in the Detailed Description, it can be seen that the description provides illustrative examples and the various features are grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed subject matter requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed configuration or operation. The following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter. 
     The claims are not intended to be limited to the aspects described herein, but are to be accorded the full scope consistent with the language claims and to encompass all legal equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirement of 35 U.S.C. § 101, 102, or 103, nor should they be interpreted in such a way.