Abstract: A fluid flow control valve uses a solenoid to control flow wherein the fluid path extends axially through the core of the solenoid. Flow is variable over the range of 0 to maximum flow and varies linearly with the voltage applied to the solenoid coil.

Abstract: Cabinet doors are supported by a hinge system that allows the doors to swing into an open space below the cabinet as they are opened. The hinge also reduces the room that must be provided in front of the cabinet to open the door. The door is mounted on hinge bars pivotally connected to a slide that rides on runners inside the cabinet. In the closed position, the bars rest on support pegs extending from the sides of the cabinet. As the door is moved forward, the hinge bars can pivot about the support pegs and the door can swing into the open space beneath the cabinet. Pivot pegs extend from each side of the cabinet in front of and below the support pegs, and the hinge bars contact the pivot pegs as the hinge bars pivot about the support pegs. The hinge bars then pivot about the pivot pegs, which control and limit the motion of the door as it moves into the fully open position.

Abstract: A dental syringe employs a single thumb or finger operated control member mounted on the syringe for regulating the flow of air or water or spray. The single control moves axially and vertically with respect to the syringe. Axial movement either forward or rearward from a rest position, initiates and controls the quantity of flow of air or water. Vertical movement of the control member initiates the flow of both air and water to produce a spray.

Abstract: An elastomeric dental impression catalyst composition for mouth temperature curing of liquid polythiopolymercaptan polymers comprised of propionic acid-treated, submicron zinc oxide and purified benzothiazyl disulfide (2,2.sup.1 -dithiobis-(benzothiazole)) is disclosed. The composition contains at least 20 parts by weight of the propionic acid-treated, submicron zinc oxide and less than 20 parts by weight of substantially pure benzothiazyl disulfide, with the amount of each of the zinc oxide and the benzothiazyl disulfide being based upon 100 parts by weight of the polymer. The final cured composition is also disclosed.

Abstract: Disclosed is a real floor for a lauter tun comprising a plurality of elongated linear troughs, each trough extending unobstructed across the bottom of the vessel and each forming a relatively shallow upward opening V-shape. The elements making up the floor are shaped to provide the lauter tun floor with a circular profile.

Abstract: A stationary seal seat for a package rotary mechanical seal is formed by compression sealing a ceramic ring within a glass coated metal ring. The ceramic provides the seat for a rotating seal member and the metal ring provides the surfaces which receive the loading forces when mounting the stationary seal seat. The glass coating on the metal functions to fuse the ceramic and metal rings together and provides a gas tight seal at the interface between the two rings. In addition, the ceramic ring has a peripheral groove defining a fluid passage for circulation of a coolant around the ceramic.

Abstract: One or more dental instruments are connected by flexible supply lines to a dental unit. A retractor is arranged to pull an extended instrument back to the unit upon being triggered. The dental instrument carries a magnet. A magnetic sensor is located near the retractor. When the instrument is passed near to sensor a signal activates the retractor which pulls in the instrument.

Abstract: A disposable filtration unit wherein the body of the unit is a unitary, one-piece molded structure having an internal flange for dividing the unit into an upper and lower chambers, the flange also providing means for supporting the filter medium.

Abstract: A foot controller for dental instruments having a pair of foot pedals which are depressed to initiate and control the rate of flow of a utility service, there being a single, variable output generator with the controller which can be operated by either the independent or simultaneous operation of the foot pedals.

Abstract: In a foot control, two or more pivoted pedals have a common main spring which provides the same resistance to all pedals. A bias arrangement keeps one pedal from falling down if the other pedal is depressed. A bias arrangement may be a horizontal rod associated with each pedal. The rod is spring biased against the pedal at a location below the pivot axis.In a two pedal embodiment both pedals can control a single electrical element. A stud extends from each horizontal rod. The stud normally prevents a spring biased pivoted member from pivoting and actuating the electrical element. When a pedal is depressed, the corresponding rod and stud move to allow the pivoted member to actuate the electric element and a corresponding switch.

Abstract: A dental delivery unit carries a number of dental instruments in nests. Upon selection, one nest is extended carrying its instrument to the dentist's group. Selection is accomplished by a priority system. Associated with each nest is a switch. Activation of any switch starts a selection period by a priority system. At the end of the selection period the nest corresponding to the last to be activated switch is extended by the priority system.If two switches are activated together the nest corresponding to the furthermost switch is extended.

Abstract: A dental chair lift mechanism employing a parallelogram lift has a linkage arrangement which offsets the horizontal component of motion produced by the parallelogram lift so that the seat of the dental chair can be elevated in a substantially straight vertical path.

Abstract: Disclosed is a method and apparatus for forming indicia on the outside of a roto-molded plastic container during the roto-molding process wherein a template bearing a mirror image of the indicia is removably affixed to the interior wall surface of a mold.

Abstract: A legrest for a dental chair has a telescopically nested section. A cable and pulley system automatically extends the nested section from the legrest as the legrest is moved from a generally vertical position to a generally horizontal position. Bias springs return the section to its nested position as the legrest moves back towards its near vertical position.

Abstract: An adjustable headrest for a dental chair having one lock for holding the headrest at an articulated position and a second lock for holding the headrest at an adjusted longitudinal position with respect to the backrest of the chair. The invention is a one hand operated lock release for operating both locks. The release can be constructed so that manipulation of a single member can accomplish sequential, independent or simultaneous operation of both locks.

Abstract: A dental cabinet, suitable for sit down dentistry, which is made by assemblying three cabinet sections. Each cabinet section has internal spaces which are in open communication with the internal spaces of the other cabinet sections. This allows the free passage of utility lines from one cabinet section to another and also permits easy access to the utility lines for installation and repair. The cabinet also can be assembled in place against a wall surface or as a free standing cabinet without the need for utility line excess openings in the walls or back of the cabinet.

Abstract: A device for monitoring a component in a fluid mixture includes a tube 1, the bore of which is divided into two chambers by a disc of solid electrolyte 1a. The electrolyte is chosen to have a conducting ion related to the component to be measured. Suspension device in the form of two resilient diaphragms 7 suspend the tube within a housing including a frame member 16 and end caps 15. Each of the diaphragms is sealed at its interface 9 with the housing, and at its interface 6 with an end of the tube. Heater 10, 11 are provided to alter the temperature of the component in each chamber and inlet 21 and outlet 22 allow fluid to enter and leave the chambers.The e.m.f. between electrodes 2 is monitored and information about the fluid mixture can be obtained depending on the temperature of the mixture sensed by a thermocouple arrangement 3.

Abstract: A furnace having an easily disassembled vacuum chamber to facilitate muffle replacement. The muffle is located over pins on the vacuum chamber base and is held against the base by a leaf spring between the muffle and the vacuum chamber top. The cylindrical wall of the vacuum chamber is correctly located with respect to the muffle by upright spacer bars upstanding from the vacuum chamber base about the periphery of the cylindrical wall. The spacer bars further serve to tie the top and base of the vacuum chamber together and against the cylindrical wall. The furnace is bottom loaded and has a door seal carried by the base so that the seal is not exposed to the direct heat from the muffle when the door is opened.

Abstract: Steel alloys having improved mechanical properties and improved ambient and low temperature toughness following the repeated thermal exposures necessary to fuse and bond ceramic or glass coatings thereto have been prepared. Phase transformation temperatures are controlled by a critical combination of manganese, silicon, and optionally, nickel, in a steel alloy of silicon, carbon, aluminum, titanium and/or niobium, phosphorus, sulfur and iron. The resulting steel alloys have good glassability, and even after glassing demonstrate excellent yield strength, ultimate tensile strength and impact strength at both ambient and low temperatures (-20.degree. F.).