Abstract: A self-calibrating powered air purifying respirator (PAPR). The PAPR comprises an electric motor mechanically coupled to a blower; an air flow sensor, and a controller coupled to the air flow sensor and to the electric motor. The controller is configured to automatically execute a one-time self-calibration by driving the electric motor to a predefined operation point, receiving an indication from the air flow sensor, determining a reference parameter based on the indication from the air flow sensor, and storing the reference parameter, wherein after completion of the one-time self-calibration the controller controls the electric motor based on the stored reference parameter.

Abstract: A low pressure warning device that comprises a piston located inside the device, where the piston partitions the device into a first chamber communicating with a first opening and a second chamber communicating with a second opening, an adjustable stop, and a spring located inside the device and configured to bias the piston to a position based on a position of the adjustable stop and based on a pressure differential between the first opening and the second opening, wherein a low pressure differential warning state is associated with a position of the piston.

Abstract: Embodiments of methods of assembling an abrasive blast respirator are disclosed. The method may comprise removably attaching an exhalation valve into an exhalation valve port of a facepiece, removably installing the facepiece into a hood, removably attaching a filter to a first inhalation valve, where the first inhalation valve is coupled to the facepiece, and removably attaching a breathing hose to a second inhalation valve, where the second inhalation valve is coupled to the facepiece.

Abstract: Embodiments relate generally to low pressure warning devices which may be worn with encapsulated protective suits and hoods by a user and may provide audio and visual alerts. In an embodiment, a low pressure warning device may comprise an earpiece operable to be retained to the ear of a user, wherein the earpiece may comprise a control system operable to sense the pressure inside the encapsulated protective suit or hood and activate the audio and/or visual alerts when necessary. In an embodiment, the low pressure warning device may be equipped with short range wireless communication capabilities.

Abstract: A powered air purifying respirator (PAPR) that alerts when remaining battery time is below a predefined threshold. The powered air purifying respirator comprises an electric motor mechanically coupled to a blower, a battery coupled to the electric motor, an alarm device, and an electronic controller. The electronic controller determines a second battery time remaining value and actuates the alarm device when the second battery time remaining value is less than a predefined threshold, wherein the controller determines the second battery time remaining value based on indexing into a look-up table of values with a first battery time remaining value and a battery voltage.

Abstract: Embodiments relate generally to a replaceable lens cartridge for use with a face mask, for example a respirator. The cartridge comprises a plurality of molded lenses, each lens sized to extend over one or more eyes of a wearer and typically having a curved shape and a plurality of catches; and a molded carrier mounting the lenses in stacked arrangement, the carrier having a first set of catches receiving the catches on one of the lenses.

Abstract: Embodiments relate generally to low pressure warning devices which may be worn with encapsulated protective suits and hoods by a user and may provide audio and visual alerts. In an embodiment, a low pressure warning device may comprise an earpiece operable to be retained to the ear of a user, wherein the earpiece may comprise a control system operable to sense the pressure inside the encapsulated protective suit or hood and activate the audio and/or visual alerts when necessary. In an embodiment, the low pressure warning device may be equipped with short range wireless communication capabilities.

Abstract: Embodiments of methods of donning and/or testing an abrasive blast respirator may be described herein. The method may comprise one or more of the following, by way of example: placing head straps over a head of a user, wherein the head straps are coupled to an abrasive blast respirator, pulling a hood of the abrasive blast respirator over the head of the user, checking a seal of a facepiece of the abrasive blast respirator by blocking an opening of an exhalation valve coupled to the facepiece and exhaling by the user, where the opening of the exhalation valve is located on an outside of the abrasive blast respirator, and checking the seal of the facepiece by blocking one or more breathing filter coupled to the outside of the facepiece and inhaling by the user.

Abstract: Embodiments of methods of assembling an abrasive blast respirator are disclosed. The method may comprise removably attaching an exhalation valve into an exhalation valve port of a facepiece, removably installing the facepiece into a hood, removably attaching a filter to a first inhalation valve, where the first inhalation valve is coupled to the facepiece, and removably attaching a breathing hose to a second inhalation valve, where the second inhalation valve is coupled to the facepiece.

Abstract: Embodiments relate to improvements for supplied-air abrasive blast respirators. Embodiments may comprise purified air via filters as a back-up air supply, with the filters typically operating automatically to provide purified air when the supplied air is compromised. Embodiments may locate elements outside of the hood to provide ready access for performing seal checks. Embodiments may incorporate noise reduction elements and/or lens protection elements as well.

Abstract: Embodiments relate generally to noise reduction techniques and systems for use with supplied air respirators. Typical embodiments may comprise porous elements located within a respirator system operable to alter the air flow pattern through the system and therefore reduce noise created in the system. These porous elements might be located within an inhalation valve, a breathing hose and/or a muffler block housing of a respirator system.

Abstract: A low pressure warning device that comprises a piston located inside the device, where the piston partitions the device into a first chamber communicating with a first opening and a second chamber communicating with a second opening, an adjustable stop, and a spring located inside the device and configured to bias the piston to a position based on a position of the adjustable stop and based on a pressure differential between the first opening and the second opening, wherein a low pressure differential warning state is associated with a position of the piston.

Abstract: A powered air purifying respirator (PAPR). The PAPR comprises an electric motor mechanically coupled to a blower, an oxygen sensor, an alarm device, and a controller coupled to the oxygen sensor and to the electric motor, wherein the controller controls the electric motor, wherein the controller determines if the oxygen concentration is deficient, and wherein the controller commands the alarm device to present an indication when the oxygen concentration is deficient.

Abstract: A probe assembly of a sensor is arranged in an airflow channel. A first probe of the assembly has an inlet. The inlet is at a first point in the airflow channel. A second probe of the assembly has an inlet. The inlet is in fluid communication with the airflow channel. The second probe inlet is closer to a surface defining a perimeter of the channel than is the first probe inlet.

Abstract: A self-calibrating powered air purifying respirator (PAPR). The PAPR comprises an electric motor mechanically coupled to a blower; an air flow sensor, and a controller coupled to the air flow sensor and to the electric motor. The controller is configured to automatically execute a one-time self-calibration by driving the electric motor to a predefined operation point, receiving an indication from the air flow sensor, determining a reference parameter based on the indication from the air flow sensor, and storing the reference parameter, wherein after completion of the one-time self-calibration the controller controls the electric motor based on the stored reference parameter.

Abstract: A probe assembly of a sensor is arranged in an airflow channel. A first probe of the assembly has an inlet. The inlet is at a first point in the airflow channel. A second probe of the assembly has an inlet. The inlet is in fluid communication with the airflow channel. The second probe inlet is closer to a surface defining a perimeter of the channel than is the first probe inlet.

Abstract: A method and apparatus for operating an powered, air-purifying respirator. The apparatus includes an air mask, an air pump, a hose connecting the mask to the air pump, a magnetic actuator disposed on a portion of the hose that engages a housing of the air pump and a controller that provides a predetermined air flow from the pump to the mask based upon a magnetic flux from the actuator.

Abstract: A method of measuring the temperature of device under test includes the steps of injecting a first current into an on-chip diode wherein a die containing the on-chip diode is under test. A second current is injected into the on-chip diode. A junction temperature is calculated based on the first current and the second current.

Abstract: An angular position sensor (100) for determining angular position includes a shaft (105) having a threaded portion (108), and a structure for engaging an external application (119). The shaft (105) includes a first permanent magnet (114). A nut (116) is threaded on the threaded portion (108). The nut (116) is formed from a first magnetic permeable material or includes a second permanent magnet (118). At least one constraint (122) is coupled to the nut (116) for preventing rotational movement of the nut (116) while allowing linear motion of the nut (116). A first magnetic sensor (120) is positioned along a length of the threaded portion (108) of the nut (116) for measuring a linear position of the nut (116). A second magnetic sensor (124) is provided for measuring an angular position of the shaft (105).

Abstract: A reflection-based optical sensor device (100) for detecting a presence of an object (110) having a detection surface (111) includes a housing (115) having first and second open volumes (120,130) including a central common portion (140) for isolating the first and second volumes. A light emitter (122) for emitting an irradiation beam (141) is contained within the first volume of the housing, wherein the light emitter is positioned in the housing so that the irradiation beam is aligned within 5 degrees of a surface normal of the detection surface (111). A light detector (132) has a detection plane (133) contained within the second volume of the housing, wherein the light detector is positioned in the housing so that the normal from the detection plane (133) is aligned within 5 degrees of the surface normal of the detection surface (111).