Abstract: An apical position detector for use in dental endodontics includes an electronic controller coupled to a conductive probe and a lip electrode. The probe is positioned in a root canal and the lip electrode contacts another location on the patient's body. The controller produces a test signal as a combination of signals at selected frequencies. The controller then monitors a voltage of the probe and extracts the amplitude and phase of each of the frequency components of the voltage at the probe. Test scores are generated from summations of the amplitudes and/or phases of the various frequency components to determine when the impedance between the probe and the lip electrode changes from a primarily reactive impedance to a primarily resistive impedance. A first test score is displayed to indicate when the impedance changes from a reactive to a resistive impedance. The second test score indicates when the measurement conditions are unsatisfactory. The test scores are displayed in bar graph or similar form.

Abstract: A heated probe and sensor tip incorporating a thermocouple located near the distal end of the probe. Improved temperature monitoring and control are achieved through placement of a thermocouple at or near the heating surface. In one embodiment of the device, the heating tip surface forms one half of a thermocouple junction. In another embodiment, a spiral resistive ribbon is formed integrally with the tip and comprises a resistive heating element. In an alternative embodiment of the device, a replaceable tip is described. A method for producing the device is also described. The thermocouple is preferably formed by the junction between the heating tip and a heating wire that surrounds the tip. The tip is preferably mounted in an insulative body which is, in turn, mounted at the distal end of a conductive support tube. Power is then delivered to the heating wire through the support tube and a lead connected to the heating tip.

Abstract: A vacuum actuated solder sucker device having a body chamber in which a vacuum is created by a vacuum source attached thereto and a cover chamber separated from the body chamber by a piston. The piston drives a primary air valve which controls the passage of air through a passageway between the body chamber and a nozzle. In a first position the primary air valve permits the application of the vacuum to the nozzle portion, and in a second position the primary air valve permits the vacuum to be reestablished within the body chamber. The primary air valve is actuated by pressure differential across the piston which is controlled by a user who covers or uncovers a bleed hole. Air pressure equalizes between the body and cover chambers through a bleed tube through the piston. The nominal pressure of the cover chamber portion in one embodiment is controlled by an adjustable bleed valve which can restrict the maximum flow of air through the bleed hole.

Abstract: A bedside television designed to permit a patient, or the like, to view the television while comfortably lying in bed without bending his neck. The bedside television device includes a television mounted substantially above the head of the patient and having a screen on which an image is displayed, the screen facing substantially upwardly, a pair of orthogonally disposed mirrors for reflecting the image displayed on the screen so as to create a virtual image of the image at a position above and forward of the patient at a distance that is further from the patient than the screen, and a mounting mechanism for mounting the television and the mirrors to a wall. The television and the mirrors are pivotally disposed in the mounting mechanism so as to be rotatable from a closed, non-viewing position to an open, viewing position.

Abstract: A method and apparatus for precisely controlling the temperature of a heated tip are disclosed. The temperature of a thermocouple within the tip is sensed at a selected rate. The sensed temperature is compared with a preselected temperature set by a user. The power provided to heat the tip is varied to cause the tip to achieve the selected temperature. If an AC power source is used, the temperature sensed at each zero crossing of the power source and the amount of power provided within that cycle is based on the temperaature of the tip sensed within the same cycle. The duration of time that heat is applied to the probe within the cycle is varied to achieve the desired temperature. If a DC power source is used, the temperature of the tip is sensed at selected intervals. The sensed temperature controls the amount of power provided to heat the tip. The exact temperature of the tip is thus advantageously controlled to provide the desired heating.

Abstract: A bi-directional reset integrator converter, including a common reset pulse generator operable by input currents of either direction, is disclosed. The reset pulse generator creates a current flow through common components in either direction, the direction depending upon the direction of the input current. Upon receipt of a reset pulse request from the integrator of the converter, the common current flow path is connected to the integrating capacitor of the converter and dumps (or withdraws) a Q = I .sup.. .DELTA.T charge that reduces the magnitude of the capacitors stored voltage. Low asymmetry and good linearity result from the use of common components in the current flow path that provides the capacitor voltage reducing charge. In addition, good scale factor stability is provided by a temperature compensating bridge circuit.