摘要:
An orthopaedic surgical instrument includes a patella trial and drill guide that may be used to both perform a surgical trial of the patellofemoral joint and guide the surgeon in drilling a number of anchor holes in the patella of the patient.
摘要:
An orthopaedic surgical instrument includes a patella trial and drill guide that may be used to both perform a surgical trial of the patellofemoral joint and guide the surgeon in drilling a number of anchor holes in the patella of the patient.
摘要:
An orthopedic surgical instrument includes a patella trial and drill guide that may be used to both perform a surgical trial of the patellofemoral joint and guide the surgeon in drilling a number of anchor holes in the patella of the patient.
摘要:
A signaling device is illustrated employing a flag supported adjacent a bottom edge of the mailbox which is pivotable downwardly out of retracted position by the act of the postman opening the mailbox. The flag device is positively operated and is positionable for maximum exposure in selectable positions.
摘要:
Highway crossing gate control circuit in which a permanent magnet motor is controlled to drive up and drive down the gate arm by utilization of a single motor control relay and controller contacts which sense the position of the gate arm. The motor polarity is reversed through utilization of the motor control relay, which is operated by a single up input signal. Provision is included for dynamic breaking on the arm moving downward after an initial drive down mode.
摘要:
An improved lighting control for a luminaire operates an LED luminaire so that its relay opens and closes at or very near the zero current cross-over point so as to reduce the in-rush current to the luminaire, and, if the relay contacts do become stuck, the photo control senses the sticking and electronically vibrates the relay to free its contacts.
摘要:
A photocontrol controls the activation of lighting based on ambient light and the time of day using a radio-controlled timer. Radio signals from a particular source of correct time, such as the National Institute for Science and Technology's WWVB radio broadcast, carry encoded time information that can be decoded by the photocontrol to ascertain the current time on start up and periodically during operation. The correct date and time information is used to synchronize the photocontrol's internal clock so that it can turn the lighting load off or on at specific times of the day in accordance with the user's needs. Thus area, business signage, and security lighting, for example, can be turned off late at night and then back on early in the morning to reduce energy consumption by the lighting during those hours when the lighting is not needed.
摘要:
A highway crossing gate control circuit is provided which minimizes the "pumping" oscillation of a highway crossing gate arm which is driven up by a permanent magnet motor. A preferred embodiment of the control circuit utilizes a p-channel MOSFET in a power down module of the control circuit to restrict power from being applied to the motor when the gate arm is in an up position and is intended to be held in the up position by a hold clear device which acts as a mechanical break. Provision is included for dynamic braking on the gate arm moving downward after an initial drive down mode.
摘要:
An improved lighting control for a luminaire operates an LED luminaire so that its relay opens and closes at or very near the zero current cross-over point so as to reduce the in-rush current to the luminaire, and, if the relay contacts do become stuck, the photo control senses the sticking and electronically vibrates the relay to free its contacts.
摘要:
A railway signal having a housing, in which the housing has an annular ledge thereon. The annular ledge has first and second opposed surfaces. One or more portions of the second ledge surface, preferably cast raised bosses, are machined so as to have a selected height. A reflector is mounted upon the first ledge surface. Also attached to the signal housing is a lamp receptacle bracket. The lamp receptacle bracket has a first end that is mounted upon the one or more machined portions of the second ledge surface. The lamp receptacle bracket also has a second end that has a lamp receptacle attached thereto. An insulating plate is disposed between the lamp receptacle flat portion and the lamp receptacle bracket flat surface.