| 摘要 |
<p>TUBULAR SOLENOID Low cost tubular solenoids are formed with a drawn case in which the pole portion forming the base of the solenoid is defined as an integral inwardly extending part of the case. A coil bobbin is formed by the injection molding of plastic material and is provided with an integral wall which is positioned in abutting relation to the inside surface of the pole portion, thereby forming a stop surface for the solenoid plunger and effectively spacing the plunger from the base. The plunger is guided on the internal surfaces of the bobbin and in one embodiment, a spun hollow sheet metal bushing is captured by the case in telescopic relation to the bobbin, and is formed with threads which receive thereon a sheet metal retaining nut. In another embodiment of the invention, a washer is threaded onto an axial extension portion of the bobbin, and the open end of the case is crimped onto an annular groove formed on the washer. In a further embodiment, the washer is injected molded in place on the bobbin. Terminal leads are molded on the bobbin and extend through apertures formed in a bobbin extension elimating the need for the placement of coil lead-in wires.</p> |
