Patent Application
20220023675
This disclosure relates generally to a powered air-purifying respirator having a tube biased toward a looped position and a method of manufacturing the same.
A powered air-purifying respirator (PAPR) is a type of personal protective equipment. A PAPR can include a blower that forces air through filter cartridges or canisters and into a breathing zone of a wearer. This provides the wearer with a filtered airflow inside, for example, a tight-fitting headpiece or loose-fitting hood or helmet. A PAPR can protect the wearer from breathing in particulates, gases, and vapors.
A powered air-purifying respirator (PAPR) assembly according to an exemplary aspect of the present disclosure includes, among other things, a tube extending from a filtration unit to a headpiece system. The tube is biased toward a looped position where the tube includes a loop.
Another example of the foregoing assembly includes the filtration unit and the headpiece system.
In another example of any of the foregoing assemblies, the headpiece system includes a hood and a mask.
Another example of any of the foregoing assemblies includes a blower of the filtration unit that forces air through a least one filter of the filtration unit and into the tube.
In another example of any of the foregoing assemblies, the tube is thermal formed when the tube is disposed about a mandrel.
In another example of any of the foregoing assemblies, the tube is polyethylene.
In another example of any of the foregoing assemblies, the tube lacks a metal or metal alloy helix reinforcement.
In another example of any of the foregoing assemblies, the tube is blow molded.
In another example of any of the foregoing assemblies, a first end portion of the tube is connected to the filtration unit and an opposite, second end portion of the tube is connected to the headpiece system.
In another example of any of the foregoing assemblies, the tube is biased toward the looped position such that a size of the loop decreases when the first end portion is moved away from the second end portion, and the size of the loop increases when the first end portion is moved toward the second end portion.
In another example of any of the foregoing assemblies, the loop extends from a first portion of the tube that connects to the filtration unit to a second portion of the tube that connects to the headpiece system.
In another example of any of the foregoing assemblies, when the PAPR assembly is worn by a user, the loop curves laterally outward and upward from the first portion to a first side of the user, and curves laterally outward and downward from the second portion to the first side of the user.
A powered air-purifying respirator (PAPR) manufacturing method according to another exemplary aspect of the present disclosure includes, among other things, reorienting a tube to have a loop by placing the tube about a mandrel, thermal forming the tube, and removing the mandrel from the tube. The tube is biased toward a looped position after the removing due to the heat-treating while the tube is reoriented to have the loop.
Another example of the foregoing method includes connecting a first end portion of a tube to a filtration unit, and connecting an opposite, second end portion of the tube to a headpiece system.
Another example of any of the foregoing methods, includes blow-molding the tube prior to the reorienting.
A powered air-purifying respirator (PAPR) manufacturing method according to yet another exemplary aspect of the present disclosure includes, among other things, connecting a first end portion of a tube to a filtration unit, and connecting an opposite, second end portion of the tube to a headpiece system. The tube is biased toward a looped position.
Another example of the foregoing method includes communicating air through the tube from the filtration unit to the headpiece system.
Another example of any of the foregoing methods includes, prior to the connecting, reorienting a tube to have a loop by placing the tube about a mandrel and then heat-treating the tube.
The embodiments, examples and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible.
The various features and advantages of the disclosed examples will become apparent to those skilled in the art from the detailed description. The figures that accompany the detailed description can be briefly described as follows:
This disclosure details a powered air-purifying respirator (PAPR). A tube of the PAPR is biased to a looped position. The tube is long enough for the PAPR to be worn by a taller user and for the taller user to bend over at the waist, for example, when wearing the PAPR.
The PAPR can instead be worn by a short statured user. A loop in the tube is larger when the PAPR is worn by the shorter user than when the PAPR is worn by the tall statured user. The biasing of the tube to the looped position helps to keep the loop from interfering with the shorter user.
The PAPR can be used by the taller user or instead used by the shorter user. Using the same PAPR design for taller and shorter users can, among other things, reduce design complexity and costs.
With reference to
In the exemplary embodiment, the headpiece system 14 includes a hood 26 and a mask 30. When a user 34 is wearing the PAPR 10, the headpiece system 14 fits over a head of the user 34, and the filtration unit 18 is secured about the waist of the user 34.
As schematically shown in
The tube 22 extends between the headpiece system 14 and the filtration unit 18. The tube 22 delivers filtered air from the filtration unit 18 to the headpiece system 14. The air moves from the tube 22 into a breathing zone of the user 34. The breathing zone is beneath the headpiece system 14. The user 34 can thus breathe air filtered by the filter of the filtration unit 18.
The tube 22 extends from a first end portion 50 to a second end portion 54. In the exemplary embodiment, the first end portion 50 is configured to engage with the filtration unit 18, and the second end portion 54 is configured to engage with the headpiece system 14.
As shown, a pipe clamp can be used to secure the first end portion 50 to a coupling that operably couples the tube 22 to the filtration unit 18. Another pipe clamp can be used to secure the second end portion 54 to a coupling that operably couples the tube 22 to a spigot of the headpiece system 14 that extends from a back of the hood 26.
In
The loop 58 curves laterally outward and upward to a left-hand side of the user 34 from the first end portion 50 of the tube 22. The loop 58 curves laterally outward and downward from the second end portion 54 of the tube 22 to the left-hand side of the user UA.
Notably, the tube 22 is biased toward the looped position shown in
As can be appreciated, stretching the tube 22 such that the first end portion 50 and the second end portion 54 move further apart from one another along an axis A causes the size of the loop 58 to decrease. That is, the diameter D of the loop decreases as the first end portion 50 and the second end portion 54 of the tube 22 are moved further apart along the axis A.
The tube 22 being biased toward the looped position of
With reference now to
In particular, after blow-molding, the tube 22 is sleeved over a mandrel 62 to position the tube 22 about the mandrel 62. The mandrel 62 can be a metal or metal alloy. Positioning the tube 22 about the mandrel 62 forces the tube 22 into the looped position.
The heat-treatment of the tube 22 involves, in the exemplary embodiment, heating the tube 22 while the tube 22 is about the mandrel 62 and then permitting the tube 22 to cool while the tube 22 is about the mandrel 62. The shape of the mandrel 62 helps to hold the tube 22 in the looped position during the heating and cooling. The forming of the tube 22 can be considered a thermal forming process or a curing process. In another example, the forming of the tube 22 can be considered an annealing or tempering process.
Heating and cooling while the tube 22 is in the looped position alters the molecular structure of the tube 22 and causes the tube 22 to be biased toward the looped position. That is, after the heating and cooling of the tube 22 in the looped position, the tube 22 will resiliently spring back or return to the looped position when removed from the mandrel 62.
Other methods of biasing the tube 22 toward the looped position of
The tube 22 is polyethylene in the exemplary embodiment, but other materials could be used. The tube 22 has annular corrugations about its longitudinal length.
Notably, the example tube 22 lacks any sort of metal or metal alloy reinforcement extending along a longitudinal length of the tube 22. That is, an axial cross-section through the tube 22 at line S-S in
With reference now to
The headpiece system 14 is further from the filtration unit 18 when the user UT wears the PAPR 10 than when the user UA or the user US wears the PAPR 10. When worn by the user UT, the loop 58 stretches out somewhat to accommodate the greater distance between the first end portion 50 and the second end portion 54 of the tube 22. In the exemplary embodiment, when the user UT is standing straight as shown in
Biasing the tube 22 toward the looped position ensures that the loop 58 will be located in an area that will not interfere with the user UT. If the tube 22 were not biased toward the looped position, the tube 22 could protrude and flop into unpredictable positions when worn by the user UT. The tube 22 if not biased to the looped position could potentially interfere with the user UT.
When the user UA wears the PAPR 10, the tube 22 does not need to extend as far as when the PAPR 10 is worn by the user UT. As the tube 22 is biased toward the looped position of
When the PAPR 10 is worn by the user US, the loop 58 continues to be formed and the diameter D of the loop 58 increases even more from that of the loop 58 in
Notably, the tube 22 can be replace a PAPR tube that is not biased toward a looped position. That is, the tube 22 can be interchangeable with PAPR tubes that are not biased toward a looped position. The interchangeability enables the tube 22 to be retrofitted within existing PAPR assemblies to make those assemblies usable for users of varying statures.
Some features of the disclosed examples include a PAPR that can be worn by relatively tall and relative short individuals without requiring differently sized tubes. The tube can be a fixed length, but meet the full range of user statures and motions, cost targets, mass requirements, and robustness, airflow, and leak requirements.
The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this disclosure. Thus, the scope of legal protection given to this disclosure can only be determined by studying the following claims.
