Patent ID: 11877604
Assignee: 3M INNOVATIVE PROPERTIES COMPANY
Field: Other consumer goods (Other fields)
Classification: CPC A | IPC A

Claim 27:
28. A maintenance-free respirator, comprising:
(a) a mask harness; and
(b) a mask body that includes at least one filtration layer, the mask body having a perimeter that includes an upper segment that comprises first and second concave segments viewable in a top view plane that is projected onto a top view of the respirator when the respirator is in an open condition, wherein the first and second concave segments are located, respectively, on first and second sides of a central plane when viewing the mask body through the top view plane,
wherein the first concave segment includes a first inflection point, a second inflection point, and a third inflection point and wherein the second concave segment includes the third inflection point, a fourth inflection point, and a fifth inflection point when viewing the mask body through the top view plane,
wherein the upper segment of the perimeter comprises a first rounded segment located approximately on the first inflection point and a second rounded segment located approximately on the fifth inflection point.