Control apparatus for blood pressure testing device

Claim 2

Apparatus for controlling the release of fluid under pressure from a blood pressure measuring device comprising inflatable means, source means providing said inflatable means with said fluid under pressure, a valve body having an internal chamber, means connecting said chamber and said inflatable means for fluid flow therebetween, valve means movable between a closed position and a plurality of open positions with respect to said valve body, each of said open positions permitting the escape of said fluid from said internal chamber, said valve means including a valve head, a valve seat communicating with said internal chamber and a valve element coupled to said valve head, said valve element and valve seat forming flow channels of different flow capacities corresponding to each of said open positions, and presettable variable control means for limiting the movement of said valve means to said open positions for providing substantially the same rate of escape of said fluid through respective ones of said flow channels for a given pressure.

Claim 3

Apparatus in accordance with claim 1 wherein said connecting means includes a passageway to permit said fluid to flow from said source means to said inflatable means and a check valve lodged in said passageway to permit the flow of said fluid out of said source means and to preclude said flow from said bore into said source means.

Claim 4

Apparatus in accordance with claim 2 wherein said valve means includes a valve stem connecting said valve head and said valve element and positioning means for normally maintaining said head in said closed position, a valve block mounted in said body having a central bore to receive said stem, wherein said valve seat is adapted to be engaged by said valve element to establish said closed position, whereby said fluid is precluded from passing from said passageway of said body to said cEntral bore of said block.

Claim 5

Apparatus in accordance with claim 3 wherein said positioning means includes a spring having one end thereof in contact with a surface of said block, and wherein said head includes a chamber for housing said spring and having a wall in contact with the opposite end of said spring.

Claim 6

Apparatus in accordance with claim 4 wherein said spring includes means for causing said valve element to be engaged with said seat to define said closed position, and wherein said head includes means for compressing said spring and separating said valve element from said seat in response to the movement of said head toward said body to define said open positions and to provide an escape path for said fluid from said inflatable means through said passageway and said central bore and into said chamber.

Claim 7

Apparatus in accordance with claim 4 wherein said stem includes a threaded end, said head includes upper and lower segments and an escape channel to atmosphere, said upper and lower segments including a threaded bore adapted to mate with said threaded end of said stem, and said lower segment including said chamber and said escape channel, said upper and lower segments being joined integrally when said upper segment is coupled to said stem.

Claim 8

Apparatus in accordance with claim 1 wherein said valve seat and said valve element are substantially conical in shape, and wherein said body includes means for receiving said conical valve element when said valve means is moved to said open positions.

Claim 9

Apparatus in accordance with claim 1 wherein said control means includes variable position means for allowing said head to assume each of said open positions with respect to said body, each of said open positions defining a different predetermined escape rate for said fluid.

Claim 10

Apparatus in accordance with claim 1 including self-closing means associated with said valve means for returning said valve means to said closed position.

Claim 11

Apparatus in accordance with claim 1 wherein said open positions are established by the relative separation between said seat and said valve element when said head is brought into contact with said control means.

Claim 12

Apparatus in accordance with claim 10 wherein said control means includes a cam rotatably mounted around said body and beneath a portion of said head, such that depression of said head brings it into contact with an edge surface of said cam.

Claim 13

Apparatus in accordance with claim 10 wherein said control means includes a truncated cylinder mounted on said body with its axis substantially parallel to the axis of said head, said cylinder including a control surface adapted to be engaged by a portion of said head to define a range of travel distances for said head.

Claim 14

Apparatus in accordance with claim 11 wherein said body includes a circumferential slot in a plane substantially transverse to the longitudinal axis of said body, and said cam comprises an eccentric disc fitted into said slot.

Claim 15

Apparatus in accordance with claim 11 wherein said cam is eccentric with respect to the longitudinal axis of said body, whereby rotation of said cam about said axis establishes a range of predetermined stroke distances for said portion of said head to travel before coming into contact with said edge surface of said cam.

Claim 16

Apparatus in accordance with claim 11 wherein said cam comprises an apertured disc formed with non-uniform radial distances between its center of rotation and its outer periphery, and wherein the one of said open positions providing the maximum predetermined escape rate is established when the minimum one of said radial distances of said disc is positioned beneath said portion of said head and the one of said open positions providing the minimum predetermined escape rate is established when the maximum one of said radial distances of said disc is positioned beneath said portion of said head.

Claim 17

Apparatus in accordance with claim 15 including slot means for facilitating the rotation of said disc around said body to define a discrete predetermined escape rate for each of said radial distances which is positioned beneath said portion of said head.

Claim 18

Apparatus in accordance with claim 1 wherein said head includes means adapted to cooperate with said control means for establishing a rapid release rate for said fluid which is maintained without operator intervention after establishment and which exceeds any of the rates of escape of said fluid through said flow channels established by said pre-settable control means.

Claim 19

Apparatus in accordance with claim 17 wherein said cooperating means includes a discrete region on a portion of said head adapted to become releasably engaged with said control means.

Claim 20

Apparatus in accordance with claim 17 wherein said head is a cylinder, said control means includes stop means for defining at least one stop position for said cylinder in moving towards said body, and said cooperating means includes a surface region on said cylinder adapted to become releasably engaged with said stop means for establishing said rapid release rate.

Claim 21

Apparatus in accordance with claim 19 wherein said cylinder further includes a housing having a spring biasing said cylinder towards said closed position and a valve stem rigid with said cylinder and connected to said valve element, said escape rates and said rapid release rate being defined by the relative separation of said valve element and said seat, wherein said stop means includes a cam mounted for rotation about said body, and wherein said surface region is a beveled portion intersecting at least the bottom surface of said cylinder, said beveled portion establishing a wedging fit with said cam to overcome the bias of said spring to establish said rapid release rate.

Claim 22

Apparatus in accordance with claim 1 wherein said valve means includes a valve stem connecting said head and said valve element, said valve seat normally receiving said valve element to establish said closed position, and wherein said flow channels are defined by the separation of said valve element and said seat, said valve element being in the shape of an inverted cone, and said seat including a chamber having a beveled region adapted to engage at least a portion of the outer surface of said inverted cone to define said closed position.

Claim 23

Apparatus for controlling the reduction of fluid pressure in a blood pressure measuring device comprising a body having a passageway transmitting said fluid to a control location, a valve at said control location comprising a valve stem having an inverted conical end and corresponding valve seat of substantially similar inverted conical shape, a clearance channel connected to said valve seat for receiving said valve stem, and movable means including said valve stem for blocking said fluid from flowing into said channel when said inverted conical end is in contact with said seat and for allowing said fluid to flow into said channel when said inverted conical end is separated from said seat, wherein said movable means includes a valve head connected to said stem and a spring for controlling the movement of said stem between said blocking and said flow positions, and including control means for establishing a plurality of predetermined repeatable flow positions when said end and said seat are separated, the extent of said flow of said fluid being proportional to the travel of said stem from said blocking position.

Claim 24

Apparatus for controlling the reduction of fluid pressure in a blood pressure measuring device comprising a body having a passageway transmitting said fluid to a control location, a valve at said control location comprising a valve stem having an inverted conical end and corresponding valve seat of substantially similar inverted conical shape, a clearance channel connected to said valve seat for receiving said valve stem, and movable means including said valve stem for blocking said fluid from flowing into said channel when said inverted conical end is in contact with said seat and for allowing said fluid to flow into said channel when said inverted conical end is separated from said seat, wherein said movable means includes a valve head connected to said stem and a spring for controlling the movement of said stem between said blocking and said flow positions, and including control means for establishing a plurality of predetermined repeatable flow positions when said end and said seat are separated, the extent of said flow of said fluid being proportional to the travel of said stem from said blocking position.