DETAILED DESCRIPTION

[0064] The present invention is herein described with reference to several preferred embodiments, each of which specifically relates to blood pressure measuring apparatus. However, it should be evident to one of sufficient skill in the field that certain other variations and modifications could be made utilizing the inventive concepts described herein, as well as alternate applications other than blood pressure measurement, including use in barometers, pressure vessel indicators, pressure sensitive switches, valves, and literally any industrial or medical device requiring a pressure responsive element. Furthermore and throughout the course of the following discussion, terms such as “upwardly”, “downwardly”, “upper”, “lower”, “top”, “bottom”, “vertically”, “horizontally”, and the like are used to provide a frame of reference with regard to the accompanying drawings. These terms, however, should not be treated as limiting with regard to the invention as described herein. In addition, a number of terms are used herein which require definitions. “Gearless” as used herein refers to any movement mechanism disposed within a gage housing which does not include a gear or gear-like element.

[0065] “Hoseless” as used herein refers to a direct connection between a gage housing and an inflatable sleeve of a pressure measuring apparatus without any intermediate hose or hoses therebetween. Several preferred embodiments of hoseless attachments for a blood pressure measuring apparatus are described throughout the course of the following discussion.

[0066] Referring to FIG. 1 , there is shown a blood pressure measuring device or apparatus 10 made in accordance with a first embodiment of the invention. The device 10 includes a substantially cylindrical gage housing 12 having an interior cavity 14 defined by a circumferential inner wall 16 , an open top end 18 , and a bottom end 20 . A viewing window or bubble 22 , made from glass, plastic, or other suitable transparent material is attached in a known manner to the open top end 18 of the gage housing 12 . The bottom end 20 of the gage housing 12 has a diameter which inwardly tapers down to a narrow downwardly extending portion 24 having a bottom opening 26 serving as an inlet port for admitting a fluid. Preferably, the diameter of the narrow extending portion 24 is about one third of the diameter of the major portion of the housing 12 , though it will be apparent from the following discussion that this parameter can be suitably varied depending upon the application.

[0067] The interior cavity 14 of the housing 12 is sized for retaining a number of component parts, including a horizontally disposed support plate 28 . The support plate 28 is a generally planar member having opposing top and bottom facing sides 30 , 32 , and a central through opening 34 . A press-fitted or otherwise suitably attached or integral sleeve 36 attached to the top facing side 30 of the support plate 28 extends into the central through opening 34 of the support plate 28 and is used for retaining a movement mechanism 40 , described in greater detail below.

[0068] The circumferential inner wall 16 of the housing 12 further includes a reflexed portion 19 which is sized for supporting an outer edge 21 of the horizontal support plate 28 immediately therebeneath and at a predetermined height within the housing 12 . The central through opening 34 is shown as being substantially aligned with the bottom opening 26 of the housing 12 , but this particular alignment is not critical to the workings of the present invention and therefore can be varied.

[0069] Referring to FIGS. 1 and 2 , a diaphragm subassembly 42 includes a flexible diaphragm 44 which is non-fixedly attached to the bottom facing side 32 of the horizontal support plate 28 . The diaphragm 44 is substantially horizontally planar and includes a plurality of wave-like surfaces 49 . An outer edge 47 of the diaphragm 44 is clamped by an O-ring 46 disposed on a circumferential ledge 45 extending upwardly from the bottom end 20 of the housing 12 . The O-ring 46 not only supports the diaphragm 44 in place, but also provides a fluid tight seal for the bottom of the interior cavity 14 .

[0070] The centermost portion of the substantially horizontally planar diaphragm 44 includes a downwardly extending section, herein after referred to as the pan 48 , which is soldered or otherwise fixed or even integral with the remainder of the diaphragm 44 . The pan 48 is a hollow cylindrical section which extends into the downwardly extending portion 24 of the housing 12 when assembled and includes a cavity 50 having a width dimension that is substantially equal to that of the press-fitted sleeve 36 . A lower end 53 of the pan 48 includes a interior contact surface 52 that is hardened.

[0071] Referring specifically to FIG. 1 , the movement mechanism 40 includes an axially displaceable shaft member 54 that is wholly enclosed within a hollow tubular member 56 with the exception of protruding top and bottom ends 57 , 55 , respectively. A thin flexible ribbon-like spring member 70 is fixedly attached at one end 61 adjacent a bottom end of the tubular member 56 to a fixed portion of the tubular member and at an opposite remaining end 59 to the axially displaceable shaft member 54 around which the ribbon spring member 70 is helically or spirally wound. The hollow tubular member 56 includes a set of external threads 73 extending over an upper portion of the length thereof that engage corresponding internal threads 75 provided in the press-fitted sleeve 36 . The ribbon spring member 70 is preferably fabricated from beryllium copper, spring steel, or other similar material.

[0072] The hollow tubular member 56 includes an integral top cap portion 58 having a diameter which is larger than that of the remainder of the member, the cap portion having a shoulder which bears against a biasing spring 68 disposed within an annular recess 69 of the press-fitted sleeve 36 . The top cap portion 58 and the biasing spring 68 are used to adjust the overall sensitivity of the movement mechanism 40 .

[0073] When correctly positioned, the majority of the movement mechanism 40 extends beneath the horizontal support plate 28 and into the cavity 50 defined in the pan 48 which is already positioned in the downwardly extending portion 24 of the housing 12 . In this position, the extending bottom end 55 of the shaft member 54 is proximate to the hardened contact surface 52 .

[0074] Still referring to FIG. 1, a dial face 63 having measuring indicia (not shown) is attached to the top facing side 30 of the horizontal support plate 28 through a center opening which is sized to fit over the press-fitted sleeve 36 . An O-ring 65 disposed in a slot 67 of the tubular sleeve 36 engages an inner edge of the dial face 63 with an indicating member 62 being mounted to the protruding top end 57 of the shaft member 54 . A preferred lightweight indicating member useful in his design is described in U.S. Ser. No. 09/471,847, the entire contents of which are herein incorporated by reference.

[0075] In operation, changes in the pressure of incoming fluid (in this example, air) entering the bottom opening 26 of the housing 12 cause corresponding movements of the diaphragm 44 . That is, the seal provided onto the outer edge 47 of the diaphragm 44 by the O-ring 46 clamping against the top face of the housing ridge 45 prevents air from further penetrating into the interior cavity 14 . Therefore, the increase in pressure causes axial movement of the diaphragm pan 48 with the interior contact surface 52 being caused to push upwardly against the bottom end 55 of the axially displaceable shaft member 54 . As a result of the upward movement of the diaphragm 44 , the top end of the ribbon spring member 70 is caused to extend relative to the fixed bottom end 61 of the spring member which is fixedly attached to the bottom end of the tubular member 56 . This extension causes the shaft member 54 to rotate about its linear axis. The rotation of the axially displaceable shaft member 54 therefore causes a corresponding circumferential movement of the indicating member 62 attached to the top end 57 of the shaft member 54 relative to the measuring indicia (not shown) on the dial face 63 .

[0076] Zero adjustment of the above pressure measuring device 10 is a relatively simple procedure, as compared with previously known devices. First, the viewing window 22 is removed from the open top end 18 of the gage housing 12 . The engagement of the O-ring 65 against the inner edge of the dial face 63 allows the dial face to be freely rotated in relation to the position of the indicating member 62 . Sensitivity adjustments can also be made at the top of the device 10 by rotating the top cap portion 58 against the biasing spring 68 within the annular recess 69 of the press-fitted sleeve 36 , so as to adjust the sensitivity of the ribbon spring member 70 for a given rotation. A similar mechanism is described in previously incorporated U.S. Pat. No. 6,168,566.

[0077] Variations of the above device are possible. For example and referring to FIG. 2 and in lieu of an O-ring, either the dial face 63 A and/or the horizontal support plate 28 A can be tapered suitably adjacent their center openings relative to a shoulder 80 provided on the tubular sleeve 36 A in order to allow the dial face to be rotated without requiring removal. Alternately, the movement mechanism 40 can include a zero adjustment feature as described in U.S. Pat. No. 5,966,829 and U.S. Pat. No. 6,168,566. In passing, it should be noted that FIG. 2 merely illustrates a portion of the overall assembly in order to distinctly facilitate the above discussion.

[0078] A housing design in accordance with a second embodiment is illustrated in FIG. 3 . Similar parts are herein labeled with the same reference numerals for the sake of clarity. As in the preceding, the device includes a gage housing 12 having an interior cavity 14 sized for retaining a diaphragm assembly 42 that includes a diaphragm 44 having a series of wave-like surfaces 49 , as well as a downwardly extending portion or pan 48 . The device further includes a substantially horizontally disposed planar support plate 28 , the housing 12 further having a downwardly extending narrowed portion 24 . A movement mechanism 40 is disposed through a central opening 34 defined in the horizontal support plate 28 such that the bottom end 55 of an axially displaceable shaft 54 of the mechanism is disposed in proximity to a hardened contact surface 52 of the pan 48 of the diaphragm assembly 42 . The diaphragm 44 in the meantime is attached, but not sealed, to the bottom facing side 32 of the horizontal support plate 28 .

[0079] A fluid, such as air, entering the gage housing 12 through a bottom opening 26 causes deflection of the pan 48 of the diaphragm 44 against the axially displaceable shaft 54 , thereby causing rotation of the shaft by means of an attached ribbon spring member 70 , according to the manner previously described.

[0080] According to this particular embodiment, the device includes a docking hub 82 that is provided on the exterior of narrow downwardly extending portion 24 of the housing 12 , the hub including a circumferential groove 114 which is sized for retaining an O-ring 118 or other similar sealing element. For example, the docking hub 82 can utilize pipe or other form of known threads (not shown). The docking hub 82 provides adequate modification to allow the device to be attached to other existing pressure device housings having pressure sources, for example, those manufactured by Welch Allyn, Inc. of Skaneateles Falls, N.Y., among others. In passing, it should be noted that the position of the bottom opening 26 of the housing 12 is not essential; that is, incoming fluid can enter the housing 12 from either a horizontally or otherwise disposed port, so long as the opening is beneath the seal that is provided by the O-ring 118 .

[0081] To further illustrate variations and referring to FIG. 4, a third embodiment of a housing 12 B made in accordance with the present invention includes a diaphragm 44 B, which unlike the preceding embodiments, is a substantially vertical member having an overall width dimension that is considerably narrower than those previously described. As a result, a horizontal support plate is not required, as in the preceding.

[0082] As in the preceding embodiments, an outer edge 47 B of the diaphragm 44 B is sealed using an O-ring 46 B or other sealing member which effectively clamps the outer edge to a shoulder of the a press-fitted sleeve 36 B. The movement mechanism 40 is disposed essentially through a center opening in a press-fitted sleeve 36 B and threaded into engagement therewith. The majority of the movement mechanism 40 is disposed within the cavity defined by the essentially vertical diaphragm 44 B, the particular diaphragm of this embodiment having vertically disposed wave-like surfaces 49 B. Adjustments to control the sensitivity of the movement mechanism 40 using biasing spring 68 B are performed in the manner previously described.

[0083] Overall, the housing of the instant embodiment defines a very shallow profile for the upper portion of the gage housing 12 B. Though not shown, the bottom end 20 B of the gage housing 12 B can be used as a docking hub to secure the gage housing into other gage housings (not shown) either as a retrofitted or as a new assembly as previously described. As further described herein, this docking hub can also permit direct hose-free connection between a gage housing and an inflatable blood pressure sleeve.

[0084] Referring to FIG. 5, a gage or instrument housing 140 formed in accordance with a fourth embodiment of the present invention is herein described in combination with a blood pressure sleeve or cuff 142 . For purposes of the present embodiment, the instrument housing 140 is used with a specific blood pressure cuff that is described in greater detail in U.S. Pat. No. 6,036,718, the contents of which are hereby incorporated in its entirety. In brief, the inflatable cuff 142 is manufactured using a pair of sleeve portions 144 , 146 that are sealed together using a series of continuous RF (radio frequency) welds to form an integral bladderless structure having an inflatable inner volume 148 . In operation, the cuff 142 is then wrapped as conventionally known about the arm 170 (partially shown) or other limb of a patient.

[0085] The gage housing 140 includes an upper housing portion 152 , a lower housing portion 154 , and a connecting intermediate portion 156 . The upper and lower housing portions 152 , 154 are substantially cylindrical in cross section and have approximately the same dimensions while the intermediate portion 156 has a substantially smaller diameter that is considerably narrower than either adjoining section, thereby defining a configuration resembling a yo-yo. According to the present embodiment, the intermediate portion 156 has a diameter which is approximately one third the diameter of the remaining portions 152 , 154 , but it will be readily apparent that this parameter can be varied depending on the relative size of the movement mechanism used therein. Each of the above portions 152 , 154 , 156 are interconnected and hollow, combining to form an interior cavity 158 .

[0086] According to this embodiment, a horizontal support plate 165 (shown in phantom), is positioned within the lower portion 154 of the housing 140 while a dial face 167 (also shown in phantom) is disposed in the upper portion 152 . A movement mechanism 171 (also shown in phantom), which is similar structurally to those previously described, interconnects the dial face 167 and the support plate 165 and is located primarily in the intermediate portion 156 .

[0087] According to this embodiment, a button-hole like slot 162 is cut both of the inner and outer sleeve portions 144 , 146 . The edges of the slot 162 are sealed. The above slot 162 provides a button-like retainment for the lower portion 154 of the housing 140 as well as the intermediate portion 156 , with the upper portion 152 protruding from the exterior of the cuff 142 . A port 176 is connected via a hose 178 to the inflatable inner volume 148 of the cuff 142 which is inflated by a pneumatic bulb (not shown) in a well known manner.

[0088] In operation, the device operates similarly to that previously described, except that a detachable stethoscope adapter 166 can also be attached to the bottom of the lower housing portion 154 , thereby forming an integral unit. The bottom of the lower portion 154 , according to this embodiment, includes an extending attachment portion 174 sized to engage a female connector 180 or other suitable means provided on the adapter 166 . All preceding known cuffs require separation between the cuff and the stethoscope. With the overall shallow profile of the above housing 140 , use of an adapter 166 permits an interconnection which is highly advantageous.

[0089] The stethoscope adapter 166 is a conical member which forms the bell of the stethoscope having connecting ear pieces (not shown) attached to a port 184 . In use, the adapter 166 is freely rotatable relative to the housing 140 , allowing examination by a patient or care giver to be performed equally well. The overall workings of stethoscopes are commonly known and do not form part of the inventive concepts described hereon.

[0090] Referring to FIGS. 6 - 8 , there is shown a blood pressure measuring device made in accordance with a fifth embodiment of the present invention. As in the preceding, similar parts are labeled with the same reference numerals for the sake of clarity. This device includes an RF-welded blood pressure sleeve 142 similar to that described in the previously incorporated '718 patent including a pair of sleeve portions 144 , 146 which are sealed together to form an integral structure and define an inflatable inner volume 148 . The sleeve 142 is sized to be wrapped around the arm or other limb of a patient (not shown) in a manner which is commonly known, and therefore requiring no further explanation. A socket 190 is disposed and fixed within an opening that is provided on the exterior of one of the sleeve portions 144 , the socket being sized to receive a mating portion of an instrument or gage housing 194 . The instrument housing 194 according to this embodiment is similar to those previously described including a narrowed bottom portion, but in which the bottom portion also includes a ball-shaped engagement or mating end 196 . When assembled, the ball-shaped engagement end 196 is fitted within the socket 190 of the sleeve in order to provide a direct fluid and sealed connection therewith, the gage housing 194 being free to pivot relative to the plane of the sleeve 142 , about the socket 190 , as shown by reference numeral 198 .

[0091] The engagement end 196 includes an opening 200 that permits fluid communication with the interior of the sleeve 142 wherein fluid (e.g., air) can enter the interior of the gage housing 194 , causing corresponding movement of a diaphragm and a contained movement mechanism (not shown in this view), in the manner previously described herein.

[0092] Preferably, the viewing window 22 of the housing 194 includes an anti-reflective coating to reduce or substantially reduce glare, with the user (physician or care giver) or patient having the ability to either rotate the housing or to pivot same in order to effectively utilize the instrument and read the dial face. As such, the gage housing 194 can effectively be used in either a right or left-armed patient measurement. A sleeve that further provides this ability with an attached gage housing is described in greater detail below.

[0093] Still referring to FIGS. 6 - 8 , the device further includes a rubberized ring-shaped guard or bumper 202 that is press-fitted into engagement about the outer periphery of the gage housing 194 , the bumper having a ridge 206 extending a predetermined distance above the viewing window 22 . The bumper 202 performs at least two functions; first, and though the present device is ultra-lightweight, the bumper additionally absorbs shock or impact loads when the housing 194 is dropped. Second, the bumper 202 also reduces the likelihood of damage to the viewing window 22 .

[0094] As described in greater detail in a succeeding embodiment, it should be noted herein that the mating or engagement end of the narrowed bottom portion of the instrument or gage housing need not include a “ball-shape” for accommodation within the sleeve socket 190 . Examples are discussed below with reference to FIGS. 9 - 14 .

[0095] Furthermore, it should also be apparent that literally any gage housings that include a pressure responsive member can be configured or retrofitted for direct engagement with a blood pressure sleeve without requiring hoses (hoseless) between the housing and the sleeve. Moreover, these housings should not be limited merely to mechanically based gage housings, as described in the foregoing, in that electronic versions can also be retrofitted to the above described sleeve if the electronic version includes or is adapted to include a suitable mating or engagement end.

[0096] One example of a prior art mechanical system is partially shown in FIG. 15 , and is defined by a gage housing 296 that retains a conventional movement mechanism 292 . The movement mechanism 292 includes a threaded end 297 extending through a bottom opening 299 of the gage housing 296 and is received into the mating threaded end of a port 300 of a tubular member 305 , the input end of which includes a pneumatic bulb 307 . In use, the output end 309 of the tubular member 305 receives a hose (not shown) that extends to a coupling of a blood pressure sleeve (not shown).

[0097] Referring to FIGS. 16 and 17 , respectively, a pair of known mechanical gage housings 294 , 306 are shown that can be interconnected to a blood pressure sleeve 324 in a manner similar that previously described. Each of these conventional housings 294 , 306 , similar to those of FIG. 15 , are less compact than those which have been expressly detailed, mainly because of the intricacy and sizing of the movement mechanism that is contained therein. Each of the gage housings 294 , 306 , however, do commonly contain a threaded engagement end or inlet port 298 , 310 , that permits fluid communication between the housing interior and the pneumatic bulb 307 , FIG. 15 . The pneumatic bulb 307 is attached using a hose (not shown) to the inlet port. As noted previously, any gage housing having an engagement or inlet end and including literally any form of movement mechanism can be reconfigured according to the present invention for hoseless interconnection with an inflatable sleeve. A number of additional examples are now described to further illustrate this point.

[0098] According to the present invention and in order to retrofit the gage housings 294 , 306 , the end of the threaded inlet port 298 , 310 can be covered with an adapter or cap 302 which is sized for sealing engagement within a socket 320 provided in an inflatable blood pressure sleeve 324 . The cap 302 and the socket 320 each include respective openings 304 , 308 , which as shown in FIGS. 16 and 17 upon attachment to the inflatable sleeve 324 , permits direct fluid communication between the interior 328 of the sleeve 324 and the interior of the housing 294 , 306 , the housing being preferably snap-fitted to the sleeve. As a result, there is no need to include the hoses which are essential to the prior art assembly of FIG. 15 , thereby greatly simplifying the use of even conventional devices by permitting direct, hose free connection to an inflatable blood pressure sleeve.

[0099] Referring to FIGS. 20 - 28 , another series of preferred embodiments are herein described to better depict the versatility achieved by the present invention. All of the preceding embodiments have referred to so-called mechanical hoseless connections, that is, each of the gage housings have included a movement mechanism which is mechanical in nature. As noted above, however, any form of movement mechanism that is capable of producing a result based on a change of pressure can be utilized.

[0100] To that end and first referring to FIGS. 20 and 21 , a blood pressure measuring assembly 400 includes a blood pressure sleeve 404 such as previously described which is bladderless, such as described in U.S. Pat. No. 6,036,718, the sleeve including a port 408 containing a small opening 412 that maintains fluid communication with the interior (not shown) of the sleeve. The port 408 permits engagement to an electronic gage module or housing 420 having a number of interior component parts, that are described in greater detail below, as well as a proximal end 424 that is sized to permit a direct releasable connection with the port without the need or requirement of additional hoses therebetween, the proximal end including an aligned end opening 428 . The sleeve 404 is inflated by means of a pneumatic bulb 434 that is tethered by a hose 438 to a coupling 442 provided on the sleeve, the coupling having an opening extending into the interior of the sleeve. A bleed valve 446 adjacent the pneumatic bulb 434 assists in the deflation of the sleeve 404 in a manner conventionally known. The sleeve 404 is bladderless, can be securably wrapped about a limb of a patent (not shown) by means of hoop and loop fastener portions 445 .

[0101] Referring to FIG. 22, a block diagram illustrates the primary componentry, in this instance, a capacitance transducer assembly 450 of an electronic pressure gauge contained within the electronic gage module 420 . This transducer assembly 450 generally includes a capacitance pressure sensor transducer 454 that is responsive to a stimulus, (in this instance, the stimulus is the input of fluid into the interior of the electronic gage module from the sleeve 404 , FIG. 20 ), the transducer being operatively connected to an oscillator circuit 458 . A measurement and processing circuit 462 is connected to the output of the oscillator circuit 458 . The measurement and processing circuit 462 includes a counter circuit 466 that is connected to a data processor 470 , each of the latter being connected to a reference oscillator 474 , the data processor being connected to user I/O devices 475 . In this instance, the I/O devices 475 include an actuable button 476 , FIG. 20 , provided on the exterior of the module as well as a display 478 , FIG. 21 .

[0102] In terms of general operation, essentially the dynamic portion of transducer 454 is a variable capacitor. As the measured environmental parameter changes (the entering fluid pressure), the capacitance changes. The oscillator circuit 458 converts this capacitance change into an AC signal. The processor 470 converts the measured frequency into the parameter (e.g., pressure) measurement and the measured parameter is then displayed upon the display 478 .

[0103] Referring to FIG. 23, a preferred capacitance sensor transducer 454 for use in the above assembly 450 is described in greater detail for exemplary purposes, the transducer including a capacitance sensor that includes a metallic conductor layer 480 formed on a surface of a circuit board 484 . A ground conductor layer 488 is disposed on the opposite surface 492 of the circuit board 484 , that also includes a dielectric material, disposed between the conductor layer 480 and the ground conducting layer 488 . A metal ring 496 is connected to the circuit board 484 by pins 500 , that are inserted through a ring conductor 504 . The metal ring 496 receives structural support from a support plate 508 that is disposed between the circuit board 484 and the metal ring 496 . The support plate 508 causes the conductor layer 480 and the support plane of the metal ring 496 to be co-planar, thereby reducing mechanical tolerance stack-up. A metallic diaphragm 512 is coupled to the circuit board 484 as sandwiched between the metal ring 496 and an O-ring 516 . Therefore, the metallic diaphragm 512 is disposed over the circuit board 484 and is juxtaposed relative to the conductor layer 480 to form a variable capacitor. The metallic diaphragm 512 is held in place by the O-ring 516 which is pressed against the diaphragm and metal ring 496 by a snap-on cap 520 . The snap-on cap 520 includes a port 522 aligned to permit fluid to enter same as stimulus as well as multiple snaps 524 that fit over the edge of the metal ring 496 . A set of electronics; more particularly, an oscillator circuit 458 and a measurement and processor circuit 462 as well as a reference oscillator 474 , for the sensor are mounted to the underside 492 of the circuit board 484 .

[0104] Referring to FIG. 24, a schematic of a preferred oscillator circuit is herein described. This circuit 458 includes a first loop having an inverter gate 530 , inverter gate 534 , resistor 538 , and a capacitive sensor 540 , such as just described in FIG. 23 , in series. An optional capacitor 542 is connected between the input of the inverter gate 530 and ground. An optional capacitor 544 is connected between the output of the resistor 538 and ground. The capacitor 542 and capacitor 544 are in parallel with stray capacitances resulting from the construction of the sensor 450 and the proximity of the oscillator 458 on the circuit board 492 to the ground conductor. A low-pass filter 548 is formed by the series resistor 538 in combination with the capacitor 542 , capacitor 544 and the stray capacitances referred to above. The oscillator circuit 458 also includes a second loop in parallel with the resistor 538 and capacitance transducer 540 . The second loop includes an inverter gate 552 in series with a resistor 556 . The output of the oscillator circuit 458 is connected to the measurement and processing circuit 462 .

[0105] This oscillator circuit 458 is a type of RC relaxation oscillator wherein the dynamic portion of the oscillator circuit 458 is the capacitance transducer 540 , as described above. Additional details concerning the above sensor and transducer assembly, including the above referred to oscillator circuit, can be found in copending U.S. Ser. No. 10/058,191 entitled: Capacitance Sensor, filed Oct. 26, 2001, the entire contents of which are herein incorporated by reference.

[0106] A cross-sectional view of the components as stored within the interior of another version of another suitable electronic gage module 560 are shown in FIG. 25 . It should be readily apparent that this module is exemplary, and that modifications and variations can be found, for example, in U.S. Pat. Nos. 5,323,782 and 5,316,006. Exterior views of this module 560 are depicted in FIGS. 27 and 28 , the module having an ovate geometry that is defined by a housing body 564 which includes a upper or major housing section 566 and a proximal engagement section 568 that is sized to be sealingly and releasably fitted into a port or socket 408 of a blood pressure sleeve 404 , such as that shown in FIGS. 20 and 21 , and in the manner previously described. The proximal engagement section 568 includes an end opening 572 extending into the interior of the module 560 and particularly to a contained capacitance transducer sensor assembly 582 , coupled to a circuit board 586 , the sensor assembly having a metallic diaphragm (not shown in this view) and operative in a manner as previously described. The interior of the module 560 further includes relevant circuitry as well as a processor 594 interconnecting the above components including a display, such as an LCD 584 that positioned relative to a viewing window 588 . Each of the above are interconnected in the manner previously described to an input means such as an ON/OFF button 598 , disposed on the upper housing section 566 of the module 560 , each being powered by batteries 600 .

[0107] The exterior of the housing body 564 further includes a peripheral bumper 576 , shown in FIGS. 27 and 28 only, that protects the upper housing section 566 when dropped. The bumper 576 is preferably raised above the LCD 584 . Within the module 560 are a number of components including the capacitance transducer sensor assembly 582 , similar to that previously described,

[0108] Referring to FIG. 26 , an alternate design for an electronic gage housing or module 640 is depicted wherein fluid enters a housing body 644 as from a sleeve (not shown) regulated by a valve 648 or pneumatic bulb (not shown) attached to a pressure-sensitive switch 652 . The sensor 656 , such as the, preceding capacitive sensor is operatively connected to receive the fluid incoming stream through a port 660 , the sensor being controlled by circuitry retained with a miniature processor 666 . Blood pressure readings are then calculated by the processor 666 for either output by a display 670 or the pressure information signal is alternately converted through appropriate means into digital values that can be transmitted wirelessly by means of a RF or IR based link 674 to a remote site (not shown).

[0109] In passing, it should further be noted that though an RF welded or bonded inflatable sleeve is described throughout, other forms of inflatable sleeves can be utilized embodying the central concepts of the present invention, including both bladderless sleeves and sleeves having bladders. In addition, other forms of systems can be employed other than the capacitance sensor described herein. For example, a strain gage including a silicon pressure sensor could be employed in combination with an analog amplifier and an A/D converter to produce a digital signal. Alternately, a diaphragm could be employed in combination with a pair of ultrasonic transducers to produce a time delay signal. According to yet another example, an optical version could be contemplated using a laser and a diffraction grating in which interference fringe counts could be used as a determining means.

[0110] Still according to another alternative, a magnetic based system could be utilized in combination with a diaphragm and an LVDT. A MEMs-based version is also possible within the ambits of the invention provided the packaging is suitably convenient for sleeve attachment. Each of the foregoing can be used with a diaphragm though use of a diaphragm may also not be required. For example, a Bourdon tube could be employed in lieu of a diaphragm. Alternately, a spring and a rolling seal piston could be substituted for the diaphragm, indicating the myriad of potential uses and applications.

[0111] Referring to FIGS. 9 - 11 , there is shown a gage or instrument housing 210 according to a sixth embodiment of the present invention. As in the preceding, the gage housing 210 is used in connection with a blood pressure measuring device and includes an upper housing portion 212 which retains a movement mechanism 214 and a narrowed lower portion 218 having a mating or engagement end 220 which is sized to engage a generally cylindrical socket 222 formed in a sleeve portion of a bladderless blood pressure cuff or sleeve 226 . Unlike the preceding embodiment, the mating end 220 of the narrowed lower portion 218 is also generally cylindrical in cross section, the end similarly including an end opening 224 , shown in FIG. 11 , which permits fluid communication with the interior of the blood pressure cuff 226 via a corresponding opening 228 also formed in the socket 222 , thereby forming a fluid inlet port.

[0112] The upper housing portion 212 of the gage housing 210 and the contained movement mechanism 214 are similar to those previously described. That is, the movement mechanism 214 includes a helically wound thin ribbon spring 240 which is attached at one end to an axially displaceable shaft member and at a second end to a tubular sleeve member in the manner described above. Changes in pressure of the cuff 226 cause fluid to enter the narrowed lower housing portion 218 through the end opening 224 , affecting a contained diaphragm 246 and causing the axially displaceable shaft member to be translated upwardly, resulting in rotation of the shaft member against the biasing of the ribbon spring 240 and circumferential movement of an indicating member 248 , attached to a protruding top end of the shaft member, relative to a dial face.

[0113] The mating end 220 of the narrowed lower housing portion 218 can include a circumferential channel or notch 250 , that is most clearly shown in FIG. 11 . The circumferential channel 250 provides a discontinuous path for shock and impact loads and, therefore, effectively cushions the contents of the gage housing 210 including the movement mechanism 214 , from shock or impact loads such as when the housing 210 lands on the narrowed lower portion 218 .

[0114] According to this embodiment and as most clearly shown in FIGS. 9 and 10 , and to further insulate the housing 210 from damage due to shock or impact loading, a rubberized peripheral guard or bumper member 232 , sized to fit over the exterior periphery of the upper housing portion 212 is press fitted into engagement therewith. The guard member 232 is similar to that previously described above in that the entire periphery of the upper housing portion 212 is covered, the guard member including a stepped portion 234 , shown in FIG. 9 A, which extends over the top of the upper housing portion, including the viewing window, and defines an air gap 236 along the outer circumferential edge thereof. The air gap 236 provides a discontinuous path for any impact loads which can occur if the gage housing 210 lands awkwardly.

[0115] Variations of the above embodiment of FIGS. 9 - 11 are possible. For example, and referring to FIGS. 12 - 14 , there is shown a gage housing 260 according to a seventh embodiment of the present invention. The gage housing 260 also includes an upper housing portion 264 and a narrowed lower housing portion 268 having an engagement end 270 which mates with a socket 222 which is formed in blood pressure sleeve 226 . The upper housing portion 264 according to this embodiment is defined by a substantially elliptical cylindrical cross section as opposed to the preceding embodiments in which the upper housing portions are substantially circular cylinders. It should be noted that other shapes or geometries could be contemplated. According to this embodiment, a circular face groove 272 provided in the bottom surface 276 of the engagement end 270 provides a similar function to the circumferential channel 250 , FIG. 11 , with regard to shock or impact loads applied to the housing if dropped or otherwise acted upon.

[0116] Otherwise, the engagement end 270 similarly engages the socket 222 of the sleeve 226 , the gage housing 260 retaining a movement mechanism (not shown) as previously described. The engagement end 270 includes an end opening 271 which permits hoseless fluid communication with the sleeve 226 , also as previously described, through a socket opening 228 which extends to the sleeve interior.

[0117] According to the instant embodiment, a rubberized guard member 280 is press fitted over the exterior periphery of the upper housing portion 264 , the guard member according to this embodiment including a radially extending portion 284 which when attached extends from the outer edge of the elliptically shaped upper housing portion 264 and similarly provides a cushioning air gap 286 which creates a discontinuity, in fact a buffer, which insulates the housing 260 from impact loads when the housing is dropped. Similar air gaps 288 are provided above the viewing window as defined in an axially extending portion 290 to provide additional protection against shock or impact loads.

[0118] As shown in FIG. 12 B, an O-ring 289 is provided within the annular air gap 288 . Additional shock resistance between adjoining portions of the housing 264 and the interior wall surface of the guard member include an annular rubberized shim 285 .

[0119] Referring to FIGS. 18 and 19 , a sleeve 344 for a blood pressure measuring apparatus 340 is herein described.

[0120] The sleeve 344 itself is constructed from a pair of sleeve portions 368 , 372 made from a polyamide or other similar fluid impermeable material which are RF welded or bonded together and define an interior chamber. The interior chamber of the sleeve 344 is inflated by means of a pneumatic bulb 356 which is tethered by tubing 360 to a barb or port 352 provided on a sleeve portion 368 , the barb having an opening which is in communication with the interior chamber of the sleeve. A check valve 364 provided adjacent to the pneumatic bulb 356 permits depressurization of the interior chamber of the sleeve 344 when the valve is opened.

[0121] The sleeve 344 includes hook and loop fastener portions (only one of which 376 being shown) on the outward facing sides of each of the sleeve portions 368 , 372 at opposite ends of the sleeve, thereby permitting the sleeve to be formed into a cylindrical shape and secured when wrapped about the limb of a patient 375 , as shown in FIG. 19 . Each hook and loop fastener portion 376 is also preferably RF welded to a sleeve portion 368 , 372 . Specific features relating to the above noted features, including the manufacture of the herein described sleeve 344 , are described in U.S. Pat. No. 6,036,718, herein previously incorporated by reference in its entirety.

[0122] When properly attached, the facing side of the sleeve portion 372 contacts the patient with the facing side of the sleeve portion 368 being exposed. According to the present embodiment, each facing side has a different color to assist in attaching same to the patient. According to the present embodiment, the sleeve 344 is two-toned with the facing side of the sleeve portion 372 having a black colored finish and the facing side of the exposed sleeve portion 368 having a lighter colored finish.

[0123] A socket or port (not shown) similar to those described above and shown for example in FIGS. 9 and 12 is also provided in the sleeve portion 368 , the socket being sized for receiving a gage housing 348 which is releasably snap-fitted in the manner previously described and defined. The gage housing 348 , when attached, can be rotated about its vertical axis, permitting easy visual access to either the care giver and/or the patient.

[0124] The gage housing 348 according to this embodiment is identical to that previously shown and described in FIG. 9 , the housing containing a bellows assembly as well as a gearless movement mechanism which operates in the manner described above to permit circumferential movement of an indicating member relative to a dial face when pressure changes within the interior chamber of the sleeve 344 cause movement to a movable surface of the bellows assembly. The gage housing 348 also preferably includes the shock/impact resistant features previously described.

[0125] An artery index marker 380 is provided adjacent the hook and loop fastener portion 376 on the facing side of the sleeve portion 368 . This marker 380 is used to align the sleeve with the brachial artery of the patient, the marker further including left and right limb indicators which are provided on respective lateral sides of the sleeve 344 . When the sleeve 344 is wrapped over the arm of the patient 375 , the marker is used to properly and circumferentially align the arm and the artery with the limb indicator pointing directly at the artery. The rotatability of the gage housing 348 within the sleeve 344 permits the sleeve having the attached gage housing to be used when attached regardless of orientation.

[0126] According to the present invention, sets of indicia 384 , 388 are also provided on the facing side of the sleeve portion 368 designating the size of sleeve being used; that is, whether the sleeve is an adult, child or neonatal cuff. An adult sleeve is shown in the present embodiment. The gage housing 348 can be releasably attached in the manner described herein to any of the above noted sleeves, regardless of size. Moreover, the above sleeve can be used with any of the above described gage housings, including the electronic modules described in FIGS. 20 - 23 .

[0127] Parts List for FIGS. 1 - 28 1

[0128] It will be readily apparent to those of ordinary skill in the field that other variations and modifications are possible within the spirit and scope of the invention as defined by the following appended claims.