Method and apparatus for logical addressing in a modular patient care system

• US 5,836,910 A
• Filed: 06/09/1997
• Issued: 11/17/1998
• Est. Priority Date: 03/13/1995
• Status: Expired due to Term

• Current Assignee: Carefusion 303 Incorporated (Becton, Dickinson & Co)
• Original Assignee: ALARIS Medical Systems, Inc. (Becton, Dickinson & Co)
• Inventors: Stone, Benson C., Domitrz, Casimer, Severe, Lon M., Richards, Edward M., Duffy, Robert J.
• Primary Examiner(s): Buiz, Michael
• Assistant Examiner(s): MENDEZ, MANUEL A
• Application Number:
  US08/866,664
• Time in Patent Office: 526 Days
• Field of Search: 604/30, 604/31, 604/49, 604/50, 604/65-67, 604/118, 604/246, 128/DIG. 12, 128/DIG. 13
• US Class Current: 604/65
• CPC Class Codes: A61M 5/1413 Modular systems comprising interconnecting elements
• CPC Class Codes: A61M 5/16827 controlling delivery of multiple fluids, e.g. sequencing, mixing or via separate flow-paths infusion of multiple fluids without using a controller A61M5/1407
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: G16H 20/17 delivered via infusion or injection
• CPC Class Codes: H01R 13/641 by indicating incorrect coupling; by indicating correct or full engagement
• CPC Class Codes: H01R 13/7038 making use of a remote controlled switch, e.g. relais, solid state switch activated by the engagement of the coupling parts
• CPC Class Codes: H01R 2201/12 for medicine and surgery

Abstract

A modular patient care system is described having unique mechanical, electrical, and logical features. An apparatus is described for allowing a modular connection arrangement wherein modules are detachably connected to each other in a convenient, flexible, interchangeable, and secure manner by providing a hinge connector pair, a specially located latch mechanism, and a guide means between any pair of modules. Additionally, an apparatus and method is described for automatic, sequential, and dynamic logical address assignment of functional units attached to the central management unit, according to their respective position in a linear array of units. Logical address assignment is designed to occur automatically upon a physical reconfiguration of the functional units, without requiring external input or a rearranged scheme for determining the relative physical positions of the functional units.

Claims

1. A modular patient care system having a plurality of units detachably coupled to form a linear array of units, said linear array having a originating end and a terminating end, each of said units having an originating side facing said originating end and a terminating side facing said terminating end, said plurality of units comprising:

an interface unit for providing a user interface to said system, said interface unit being capable of providing sequential logical ID'"'"'s;

a plurality of functional units, each functional unit having a unique resettable logical ID; and

a communications bus formed by said linear array of units for allowing each functional unit to communicate with said interface unit and receive commands therefrom;

wherein said patient care system is capable of automatically assigning said sequential logical ID'"'"'s to said functional units according to their sequential positions in said linear array without requiring external user input or a prearranged locational scheme for indicating a relative physical position of a functional unit.

2. A modular patient care system having a plurality of units detachably coupled to form a linear array of units, said linear array having a originating end and a terminating end, each of said units having an originating side facing said originating end and a terminating side facing said terminating end, said plurality of units comprising:

an interface unit for providing a user interface to said system, said interface unit being capable of providing sequential logical ID'"'"'s;

a plurality of functional units, each functional unit having a unique resettable logical ID; and

a communications bus formed by said linear array of units for allowing each functional unit to communicate with said interface unit and receive commands therefrom;

wherein each functional unit further comprises;

means for detecting a first signal provided by an adjacent originating side unit, said first signal having a first value or a second value different from said first value;

means for providing said first signal to an adjacent terminating side unit;

means for generating a second signal, said second signal being equal to

(a) said first value if the functional unit is at said originating end of the linear array, or

(b) the value of said first signal provided by said adjacent originating side unit if the functional unit is not at the originating end of the linear array;

means for setting said first signal to said second value upon receiving a first command from said interface unit;

means for receiving one of said sequential logical ID'"'"'s from said interface unit upon detecting said second signal to be equal to said first value after having received said first command;

means for setting said first signal equal to said first value after having received said logical ID;

whereby

said patient care system is capable of assigning said sequential logical ID'"'"'s to said functional units according to their sequential positions in said linear array.

3. The modular patient care system according to claim 2, said system further comprising a unit detect bus formed by said plurality of functional units and said interface unit, said unit detect bus having a first state and a second state different from said first state, each of said functional units further comprising pulling means coupled to said unit detect bus for pulling said unit detect bus to said second state,

wherein said interface unit further comprises pulling means capable of pulling said unit detect bus to said first state when none of said functional unit pulling means are pulling said unit detect bus to said second state,

wherein each of said functional units further comprises means for pulling said unit detect bus to said second state, and thereafter releasing said unit detect bus, upon initial connection of said functional unit to said linear array of units, and

wherein said interface unit further comprises means for detecting said pulling and releasing of said unit detect bus and means for sending said first command to said functional units responsive thereto,

whereby

said patient care system is capable of assigning sequential logical ID'"'"'s to said functional units according to their sequential positions in said linear array upon the addition of an added functional module to said linear array.

4. The modular patient care system of claim 2, said system further comprising:

an originating unit detect bus formed by said originating side functional units and said interface unit; and

a terminating unit detect bus separate from said originating unit detect bus formed by said interface unit and the set of functional units located on the terminating side of said interface unit, each of said originating and terminating unit detect buses having a first state and a second state different from said first state, each of said functional units further comprising pulling means coupled to said originating or terminating unit detect bus for pulling said originating or terminating unit detect bus to said second state, respectively;

wherein said interface unit further comprises originating side pulling means capable of pulling said originating unit detect bus to said first state when none of said forcing means are pulling said originating unit detect bus to said second state,

wherein said interface unit further comprises terminating side pulling means capable of pulling said terminating unit detect bus to said first state when none of said forcing means are pulling said terminating unit detect bus to said second state,

wherein each of said functional units further comprises means for pulling said originating or terminating unit detect bus to said second state, and thereafter releasing said originating or terminating side unit detect bus, upon initial connection of said functional unit to said originating or terminating end, respectively, of said linear array of units,

and

wherein said interface unit further comprises means for detecting said pulling and releasing of said originating or terminating unit detect bus, and means for sending said first command to said functional units responsive to a pulling and releasing of said originating bus and means for sending a second command responsive to said pulling and releasing of said terminating unit detect bus,

whereby

said patient care system is capable of initiating a logical address assignment procedure upon the addition of a new functional unit to said linear array of units.

5. The modular patient care system of claim 4,

wherein said functional units further comprise means for pulling said originating or terminating unit detect bus to said second state upon receiving said first command from said interface unit,

wherein said functional units further comprise means for releasing said originating or terminating unit detect bus upon receiving said logical ID and setting said second signal equal to said first value,

wherein said interface unit comprises means for detecting the releasing of said originating unit detect bus to said first state after all originating side functional units have released said originating unit detect bus, and means for providing said first signal to an adjacent terminating side unit, said first signal being equal to said first value upon said detection of the releasing of said originating unit detect bus;

whereby

said patient care system is capable of assigning sequential logical ID'"'"'s to said all of said functional units according to their sequential positions in said linear array upon the addition of an added functional module to said originating side of said linear array.

6. The modular patient care system of claim 5,

wherein said functional units further comprise means for pulling said originating or terminating unit detect bus to said second state upon both (a) receiving said second command from said interface unit while (b) not yet having an ID assigned,

wherein said interface unit further comprises a means for storing the number of functional units already having logical ID'"'"'s,

whereby

said modular patient care system is capable of assigning sequential logical ID'"'"'s to functional modules added to the terminating end of the linear array without reassigning logical ID'"'"'s to those functional modules already in the linear array.

7. The modular patient care system of claim 6, said interface unit further comprising:

a memory for storing functional unit specific information for at least one of said functional modules indexed according to the logical ID of said at least one functional unit;

means for transferring the functional unit specific information corresponding to said at least one functional unit in said memory to a next sequential logical ID subsequent to the addition of said added unit to said originating side.

8. The modular patient care system of claim 6, said first signal being an ID enable out signal, said first value being a logic high voltage signal, said second value being a logic low voltage signal, said means for detecting said first signal being an ID enable in lead, said means for generating said second signal comprising a pullup resistor coupled between said ID enable in lead and a constant voltage source, wherein said ID enable in lead is pulled up to said logic high voltage signal when not connected to an ID enable out lead of an adjacent originating side unit.

9. The modular patient care system of claim 8, said first command being a global set ID command, said second command being an unassigned unit set ID command, said first state being a logic high voltage, said second state being a logic low voltage, said pulling means of each of said functional units comprising a grounding transistor coupled between a ground and said originating or terminating unit detect buses, said releasing means of each of said functional units comprising said grounding transistor, said interface unit originating side pulling means comprising:

an originating unit detect lead for coupling to said originating unit detect bus; and

a left pullup resistor coupled between said originating unit detect lead and a constant voltage source;

wherein said originating unit detect lead is pulled high by said left pullup resistor upon release of said unit detect bus by all of said releasing means.

10. A modular patient care system having a plurality of units detachably coupled to each other to form a linear array, said linear array having a originating end and a terminating end, said units each having an originating side facing said originating end and a terminating side facing said terminating end, said linear array comprising:

an interface unit for providing a user interface to said system;

a plurality of functional units, each functional unit being capable of providing patient therapies or monitoring, each functional unit having a unique resettable logical ID, each functional unit comprising;

a communications bus portion for forming a common communications bus;

a unit detect bus portion for forming a unit detect bus;

means for providing an id_-- enable_-- out signal to a unit abutting said terminating side, said id_-- enable_-- out signal having a value ENABLE or DISABLE;

means for generating an id_-- enable_-- in signal, wherein said id_-- enable_-- in signal is equal to

(a) ENABLE if the functional unit is at said originating end of said linear array, or

(b) the id_-- enable_-- out signal of a unit abutting said originating side otherwise;

means for receiving commands from said interface unit over said communications bus;

means for pulling down said unit detect bus to a LOW state and setting said_-- id enable_-- out signal to DISABLE responsive to a first command from said interface unit;

means for detecting the state of said id_-- enable_-- in signal;

means for receiving a unique logical address from said interface unit upon (1) having received said first command, and (2) detecting the state of id_-- enable_-- in to equal ENABLE;

means for setting said logical ID equal to said unique logical address; and

means for setting said id_-- enable_-- out signal to ENABLE and for releasing said unit detect bus upon setting said logical ID;

whereby

said patient care system is capable of assigning sequential logical ID'"'"'s to said functional modules according to their respective positions in said linear array.

11. The modular patient care system of claim 10, wherein said interface unit comprises:

means for pulling said unit detect bus to a high logic state;

a communications bus portion for forming said common communications bus among said units;

means for detecting said LOW state of said unit detect bus upon initial power-up or upon the addition of a new functional unit;

means for detecting the releasing of said unit detect bus;

means for transmitting a PULL_-- UNIT_-- ID_-- LOW command over said communications bus responsive to said LOW state and said releasing of said unit detect bus;

means for assigning sequential logical addresses to said functional units during a period in which said unit detect bus is pulled LOW.

12. In a modular patient care system having a plurality of units detachably coupled to form a linear array of units having an originating end and a terminating end, each unit having an originating side facing said originating end and a terminating side opposite said originating end, the linear array of units comprising an interface unit for providing sequential logical ID'"'"'s and a plurality of functional units requiring an assignment of a one of said sequential logical ID'"'"'s, a method comprising the steps of:

generating a value ENABLE or DISABLE at an ID enable in lead of each functional unit;

transmitting a sequential logical ID to all functional units over a common communications bus formed by functional units and the interface unit;

receiving the sequential logical ID at that functional unit which (1) detects a value ENABLE at its ID enable in lead, and (2) has not yet been assigned a logical ID;

setting an ID enable out lead of that functional unit to the value ENABLE after receiving the sequential logical ID, for generating the value ENABLE at the ID enable in lead of an adjacent terminating side unit.

13. The method of claim 12, each functional unit having a pullup resistor connected between the ID enable lead and a constant voltage source with the value ENABLE, the step of generating the value ENABLE or DISABLE at the ID enable in lead comprising the step of (1) if the functional unit is at the originating end of the linear array, pulling up the value at the ID enable in lead to ENABLE, and (2) otherwise, connecting the ID enable in lead to the ID enable out lead of the originating side adjacent unit to assume the value of the ID enable out lead of the originating side adjacent unit.

14. The method of claim 13, further comprising the steps of:

determining whether an additional unit has been added to the originating end of the linear array;

determining whether an additional unit has been added to the terminating end of the linear array;

if an additional unit has been added to the originating end of said linear array, assigning sequential logical ID'"'"'s to all functional units;

if the additional unit has been added to the terminating side of said linear array, assigning a sequential logical ID only to the additional unit.

15. The method of claim 14, said step of determining whether an additional unit has been added to the originating end of the linear array comprising the step of detecting a pulling down, followed by a releasing, of an originating unit detect bus formed by the originating functional units and the interface unit, the originating functional units being those units on the originating side of the interface unit, the originating unit detect bus being capable of being pulled up by the interface unit upon being released by all originating functional units, the added functional unit being capable of pulling down and then releasing the originating unit detect bus on power-up.

16. The method of claim 15, said step of determining whether an additional unit has been added to the terminating end of the linear array comprising the step of detecting a pulling down, followed by a releasing, of an terminating unit detect bus formed by the terminating functional units and the interface unit, the terminating unit detect bus being capable of being pulled up by the interface unit upon being released by all terminating functional units, the added functional unit being capable of pulling down and then releasing the terminating unit detect bus on power-up.

17. The method of claim 16, said step of assigning sequential logical ID'"'"'s to all functional units comprising the steps of:

sending a first command to all functional units instructing each unit to pull down the originating or terminating unit detect bus to which it is connected;

setting an interface unit ID enable out lead to the value DISABLE, the interface unit ID enable out lead being coupled to the ID enable in lead of an adjacent terminating side functional unit;

assigning sequential logical ID'"'"'s to all originating side functional units;

detecting when all originating side functional units have been assigned logical ID'"'"'s;

setting the interface unit ID enable out lead to ENABLE;

assigning sequential ID'"'"'s to all terminating side functional units.

18. The method of claim 17, each functional unit being capable of releasing the unit detect bus to which it is connected upon receiving a sequential logical ID, the step of detecting when all originating side functional units have been assigned logical ID'"'"'s comprising the step of detecting the releasing of the originating unit detect bus.

19. A computer-readable medium which can be used to direct an interface unit of a modular patient care system to assign sequential logical unit ID'"'"'s to a plurality of functional units attached to the interface unit so as to form a linear array of units having an originating end and a terminating end, the interface unit and the functional units each having an originating side facing the originating end and a terminating side opposite the originating side, the computer-readable medium comprising:

means for directing the interface unit to send commands and receive information over a common communications bus formed by the interface unit and the attached functional units;

means for directing the interface unit to detect system power-up or the attachment of additional functional units and for directing the interface unit to send a first command to all attached functional units responsive thereto;

means for directing the interface unit to transmit sequential logical ID'"'"'s to all functional units over the common communications bus, for receiving by a single functional module which has (1) received the first command, (2) received an enabling signal from an originating side adjacent unit or is the functional unit at the originating end, and (3) has not yet received a logical ID after receiving the first command;

means for directing the interface unit to detect when all originating side functional units have received logical ID'"'"'s and for directing the interface unit to transmit an enabling signal to a terminating side adjacent functional unit responsive thereto.

20. The computer-readable medium of claim 19, the means for directing the interface unit to detect the attachment of additional functional units further comprising:

means for directing the interface unit to detect a pulling and releasing of a voltage signal present at an originating unit detect bus lead, the originating unit detect bus lead for contacting an originating unit detect bus formed by the originating side functional units, each functional unit being capable of pulling the originating unit detect bus to a second voltage, each functional unit also being capable of releasing the originating unit detect bus, the originating unit detect bus lead being connected to a constant first voltage through a pullup resistor in the interface unit, whereby the first voltage is present at the originating unit detect bus lead only when no originating side functional module is pulling the originating unit detect bus to the second voltage, wherein each functional unit is capable of pulling and then releasing said originating unit detect bus upon initial attachment to the originating end of the linear array; and

means for directing the interface unit to detect a pulling and releasing of a voltage signal present at a terminating unit detect bus lead, the terminating unit detect bus lead for contacting a terminating unit detect bus formed by the terminating side functional units, each functional unit being capable of pulling the terminating unit detect bus to a second voltage, each functional unit also being capable of releasing the terminating unit detect bus, the terminating unit detect bus lead being connected to a constant first voltage through a pullup resistor in the interface unit, whereby the first voltage is present at the terminating unit detect bus lead only when no terminating side functional module is pulling the terminating unit detect bus to the second voltage, wherein each functional unit is capable of pulling and then releasing said terminating unit detect bus upon initial attachment to the linear array.

21. The computer-readable medium according to claim 20, the means for directing the interface unit to detect when all originating side functional units have received logical ID'"'"'s comprising:

means for directing the interface unit to transmit as the first command a command directing all functional units to pull the originating or terminating unit detect bus to the second value; and

means for directing the interface unit to detect the state of the originating unit detect lead subsequent to transmitting the first command, said functional modules being capable of releasing the originating or terminating unit detect bus upon being assigned a logical ID, whereby the originating unit detect lead will contain the first voltage after all originating side units have been assigned logical ID'"'"'s.

22. A computer-readable medium which can be used to direct a functional unit of a modular patient care system in receiving a sequential logical unit ID from an interface unit, the modular patient care system having a plurality of functional units attached to the interface unit so as to form a linear array of units having an originating end and a terminating end, the interface unit and the functional units each having an originating side facing the originating end and a terminating side opposite the originating side, the computer-readable medium comprising:

means for directing the functional unit to pull and then release a unit detect bus upon initial power-up of the functional module, the unit detect bus formed by the functional unit and other functional units, each of the functional units being capable of pulling the unit detect bus to a second voltage, each functional unit also being capable of releasing the originating unit detect bus;

means for directing the functional unit to sense the voltage of an ID enable in lead, the voltage having the value ENABLE or DISABLE, the ID enable in lead being for connecting to and assuming the value of an ID enable out lead of an adjacent originating unit side functional unit, the ID enable in lead being configured so as to have the value ENABLE if the functional module is at the originating end;

means for directing the functional unit to receive a first command from the interface unit over a common communications bus and for pulling the unit detect bus to the second value responsive thereto;

means for directing the functional unit to receive a unique sequential logical ID from the interface unit upon (1) having received the first command, and (2) detecting the voltage of the ID enable in lead to be ENABLE;

means directing the functional unit to set an internal logical address equal to the value of the sequential logical ID;

means for directing the functional unit to release the unit detect bus after receiving the logical ID; and

means for directing the functional unit to set the value of the ID enable out lead to ENABLE after receiving the logical ID.