Negative pressure respirator shells

Claim 2

A portable negative pressure respirator shell comprising a plurality of generally curved and substantially rigid shell sections cooperable to provide an open ended shell which embraces a patient's torso when worn by the patient, being positioned to extend downwardly from over the chest about the diaphragm and abdomen to define a chamber between the shell and the patient's torso, port means to permit application of a negative pressure to said chamber, and resilient flexible sealing lips formed of overlaid strips of resilient material of successively reducing width disposed along longitudinally spaced edges of the shell sections which bound the open ends of the assembled shell, said lips being of outwardly increasing flexibility, thereby to aid in providing an airtight engagement with the body surface of the patient on the application of a negative pressure to said chamber.

Claim 3

A portable negative pressure respirator shell comprising a plurality of generally curved and substantially rigid shell sections cooperable to provide an open ended shell which embraces a patient's torso when worn by the patient, being positioned to extend downwardly from over the chest about the diaphragm and abdomen to define a chamber between the shell and the patient's torso, port means to permit application of a negative pressure to said chamber, and resilient flexible sealing lips disposed along longitudinally spaced edges of the shell sections which bound the open ends of the assembled shell, said lips being of outwardly increasing flexibility thereby to aid in providing an airtight engagement with the body surface of the patient on the application of a negative pressure to said chamber, said shell sections having integral wholly outstanding ribs which extend adjacent said edges and include inturned longitudinally outwardly directed inclined marginal portions terminating at said edges, and wherein said sealing lips are rigidly coupled to said marginal portions of the outstanding ribs as inwardly inclined longitudinal extensions of the shell section.

Claim 4

A portable negative pressure respirator shell comprising a plurality of generally curved and substantially rigid shell sections cooperable to provide an open ended shell which embraces a patient's torso when worn by the patient, being positioned to extend downwardly from over the chest about the diaphragm and abdomen to define a chamber between the shell and the patient's torso, port means to permit application of a negative pressure to said chamber, and resilient flexible sealing lips disposed along longitudinally spaced edges of the shell sections which bound the open ends of the assembled shell, said lips being of outwardly increasing flexibility thereby to aid in providing an airtight engagement with the body surface of the patient on the application of a negative pressure to said chamber, said shell sections having integral wholly outstanding ribs which extend adjacent said edges and include inturned longitudinally outwardly directed inclined marginal portions terminating at said edges, and wherein said sealing lips are rigidly coupled to said marginal portions of the outstanding ribs as inwardly inclined longitudinal extensions of the shell section.

Claim 5

A portable negative pressure respirator shell comprising a plurality of generally curved and substantially rigid shell sections cooperable to provide an open ended shell which embraces a patient's torso when worn by the patient, being positioned to extend downwardly from over the chest about the diaphragm and abdomen to define a chamber between the shell and the patient's torso, port ments to permit application of a negative pressure to said chamber, and resilient flexible sealing sections which bound the open ends of the assembled shell, said lips being of outwardly increasing flexibility thereby to aid in providing an airtight engagement with the body surface of the patient on the application of a negative pressure to said chamber, and a beading along said edges, the sealing lips being coupled to said edges by being partially encased in the beading to form a mechanically rigid connection with said edges.

Claim 6

A portable negative pressure respirator shell comprising a plurality of generally curved and substantially rigid shell sections cooperable to provide an open ended shell which embraces a patient's torso when worn by the patient, being positioned to extend downwardly from over the chest about the diaphragm and abdomen to define a chamber between the shell and the patient's torso, port ments to permit application of a negative pressure to said chamber, and resilient flexible sealing sections which bound the open ends of the assembled shell, said lips being of outwardly increasing flexibility thereby to aid in providing an airtight engagement with the body surface of the patient on the application of a negative pressure to said chamber, and a beading along said edges, the sealing lips being coupled to said edges by being partially encased in the beading to form a mechanically rigid connection with said edges.

Claim 7

A respirator comprising a plurality of generally curved and substantially rigid shell sections cooperable to provide an open ended shell which embraces a patient's torso when worn by the patient, being positioned to extend downwardly from over the chest about the diaphragm and abdomen to define a chamber between the shell and the patient's torso, port means to permit application of a negative pressure to said chamber, and resilient flexible sealing lips disposed along longitudinally spaced edges of the shell sections which bound the open ends of the assembled shell, said lips being of outwardly increasing flexibility, thereby to aid in providing an airtight engagement with the body surface of the patient on the application of a negative pressure to said chamber; structure defining a cavity having an air intake port open to atmosphere and a suction port communicable with the port means of the shell; means for applying continuous air suction to said cavity to induce a vacuum therein; and valve means to intermittently and temporarily reduce the degree of vacuum in said cavity, which valve means includes a butterfly damper rotatable between a position closing said air intake port and a position allowing air inflow through said air intake port whilst simultaneously substantially restricting air inflow through said suction port, thus reducing the suction applied to said chamber within the shell.

Claim 8

A respirator comprising a plurality of generally curved and substantially rigid shell sections cooperable to provide an open ended shell which embraces a patient's torso when worn by the patient, being positioned to extend downwardly from over the chest about the diaphragm and abdomen to define a chamber between the shell and the patient's torso, port means to permit application of a negative pressure to said chamber, and resilient flexible sealing lips disposed along longitudinally spaced edges of the shell sections which bound the open ends of the assembled shell, said lips being of outwardly increasing flexibility, thereby to aid in providing an airtight engagement with the body surface of the patient on the application of a negative pressure to said chamber; structure defining a cavity having an air intake port open to atmosphere and a suction port communicable with the port means of the shell; means for applying continuous air suction to said cavity to induce a vacuum therein; and valve means to intermittently and temporarily reduce the degree of vacuum in said cavity, which valve means includes a butterfly damper rotatable between a position closing said air intake port and a position allowing air inflow through said air intake port whilst simultaneously substantially restricting air inflow through said suction port, thus reducing the suction applied to said chamber within the shell.

Claim 9

A power unit according to claim 4 further comprising a partition defining one wall of the cavity, wherein the air suction means and the air intake port open to said cabity in a common plane through the partition.

Claim 10

A power unit according to claim 4 wherein the air intake port and suction port are adjacent each other in respective walls of said cavity and wherein the butterfly damper is rotatably mounted substantially diametrally of the air intake port.

Claim 11

A respirator device according to claim 1, 2, 3, 4, 5 or 6 wherein the sealing lips are of reducing thickness and increasing resilience in a direction outwardly of the respective edges.

Claim 12

A respirator device according to claim 1, 2, 3, 4, 5 or 6 wherein at least one of the sealing lips carries at or adjacent a portion of its outer margin a flexible and compressible pad as a further aid in establishing said airtight engagement.

Claim 13

A respirator device according to claim 1, 2, 3, 4, 5 or 6 further including a cushion fitted internally within one shell section.

Claim 14

A power unit for applying intermittent negative pressure to a chamber defined by a respirator shell, comprising: structure defining a cavity having an air intake port open to atmosphere and a suction port communicable with the port means of the shell; means for applying continuous air suction to said cavity to induce a vacuum therein; and valve means to intermittently and temporarily reduce the degree of vacuum in said cavity, which valve means includes a butterfly damper rotatable between a position closing said air intake port and a position allowing air inflow through said air intake port whilst simultaneously substantially restricting air inflow through said suction port, thus reducing the suction applied to said chamber within the shell.

Claim 15

A power unit for applying intermittent negative pressure to a chamber defined by a respirator shell, comprising: structure defining a cavity having an air intake port open to atmosphere and a suction port communicable with the port means of the shell; means for applying continuous air suction to said cavity to induce a vacuum therein; and valve means to intermittently and temporarily reduce the degree of vacuum in said cavity, which valve means includes a butterfly damper rotatable between a position closing said air intake port and a position allowing air inflow through said air intake port whilst simultaneously substantially restricting air inflow through said suction port, thus reducing the suction applied to said chamber within the shell.

Claim 16

A power unit according to claim 10 further comprising a partition defining one wall of the cavity, wherein the air suction means and the air intake port open to said cavity in a common plane through the partition.

Claim 17

A power unit according to claim 10 wherein the air intake port and suction port are adjacent each other in respective walls of said cavity and wherein the butterfly damper is rotatably mounted substantially diametrally of the air intake port.

Claim 18

A respirator device according to claim 2, 3, 4, 5 or 6 wherein the sealing lips are formed of overlaid strips of resilient material of successively reducing width.