Abstract: A hearing protector comprises a hearing hood (2), a microphone (7), a loudspeaker and an amplifier. The hearing hood (2) has passive noise damping. The microphone (7) is disposed exteriorly on the hearing protector, while the loudspeaker is disposed inside the hood. The amplifier amplifies and transmits the signals from the microphone (7) to the loudspeaker. The noise damping of the hearing hood (2) is broad band. The frequency range of the amplifier corresponds to the frequency range of human speech. The amplification of the amplifier is variable and the greatest amplification is such that the sum total of the sound levels that are caused, on the one hand, by ambient sound passing through the hood (2) and, on the other hand, by sound from the loudspeaker amounts to a maximum, predetermined value.

Abstract: An ear cup with a microphone apparatus including an inner cup portion, for forming a noise damping space, and an outer cup portion for forming a space for accommodating electronics and/or a current source. The inner cup portion and the outer cup portion are separated by a partition. The inner cup portion has a pocket and two opposingly located recesses in which a bracket for a microphone is disposed. Over the microphone, a windshield is provided, this protecting the microphone from being damaged and also damping wind noise. The windshield has an outer configuration that may be seen as a continuation of the outer cup portion, in order to prevent turbulence in the region of the windshield. The windshield is produced from a porous material, which is surrounded by a mounting frame having nap catches for engagement in snap catches.

Abstract: An ear cup for a hearing protection unit including an inner cup portion which defines a noise damping space facing towards the user. The ear cup further has an outer cup portion for accommodating electronics and/or a current source. The inner cup portion and the outer cup portion are separated by a partition which is of one piece manufacture with the inner cup portion. The partition is substantially closed, with the exception of an opening in which a fixing portion on a bracket is disposed. The fixing portion (9) has a central channel (15) for the passage of supply conductors to a loudspeaker. The supply conductors have a contact placed on the outside of the partition for connection of the electronics. The bracket also has a baffle plate which extends along the periphery of the loudspeaker.

Abstract: A protective automatic darkening filter (ADF) and an associated tool, such as a welding torch, are controlled by a corresponding communication unit. The invention helps to ensure that the tool is not activated before the ADF has reached its dark state. A communication channel between the communication unit and the ADF may be established using a wired or wireless medium.

Abstract: A protective automatic darkening filter (ADF) includes automatic power management capabilities. The ADF includes a power management control unit that controls power to the ADF based on whether or not the ADF is currently in use. In one embodiment, to determine whether the ADF is in use, the power management control unit includes a motion sensor that senses movement of the ADF and controls power to the ADF based on the sensed movement.

Abstract: The invention relates to the use of RFID systems for use with items of interest having RFID tags, such as in a library. The invention has particular applicability to determining the location, order, and other information regarding such items.

Abstract: A library terminal permits a user to execute a loan transaction without assistance. The library terminal (i) provides a visible scan line from a bar code reader indicating the correct positioning of the bar code on a circulating item, (ii) leads a user through a loan transaction, (iii) provides an explicit feedback to a user when an article has an improper position on the article receiving area, (iv) both checks out and checks in circulating items, (v) stores fonts in bit maps of screen displays instead of in a separate font memory, (vi) integrates a security marker reader, a printer, and a controller in the same housing, (vii) processes financial transactions related to the borrowing of circulating items, and/or (viii) displays actions for helping the user to correct errors in use of the terminal.

Abstract: A powered air purifying respirator and method for directing a forced flow of air to a wearer. A battery operatively powers a fan fluidly coupled with the air flow path which exhibits, in some circumstances, a passivation. A voltage delay sensing circuit, operatively coupled to the battery, provides an indication related to the passivation. A signal may provide an indication to a user of the passivation of the power source. A correction circuit may correct such passivation.

Abstract: A protective automatic darkening filter construction 10 includes two low twist liquid crystal cells 26, 30 interspersed between a series of offset polarizers 24, 28, 32. The resulting construction provides improved homogeneity in the dark state as viewed by the user over a large viewing angle. By reducing variations in shade, visibility through the filter may be improved.

Abstract: A protective automatic darkening filter (ADF) and an associated tool, such as a welding torch, are controlled by a corresponding communication unit. The invention helps to ensure that the tool is not activated before the ADF has reached its dark state. A communication channel between the communication unit and the ADF may be established using a wired or wireless medium.