Abstract: A free piston Vuillermier machine which is an external combustion heat machine using a regenerative cycle, wherein a low-temperature displacer is made hollow to form a low-temperature displacer gas spring chamber, a low-temperature displacer rod is made hollow to form a hollow chamber for accommodating a high-temperature displacer rod therein as well as a high-temperature displacer gas spring chamber. Further, in the above configuration, a gas spring chamber passage may be formed to make the high-temperature displacer gas spring chamber communicate with the low-temperature displacer gas spring chamber. A high-temperature displacer mechanical spring may be provided in the high-temperature displacer gas spring chamber, and a low-temperature displacer mechanical spring mounted on the low-temperature displacer rod may be provided in the low-temperature displacer gas spring chamber.

Abstract: This invention relates to a connector engagement detecting apparatus having a compact checking structure.

Abstract: A connector includesvone connector housing having a flexible lock arm, other connector housing having an engagement portion corresponding to the flexible lock arm, a short-circuiting contact member having resilient contact pieces, the short-circuiting contact member arranged on a displacement allowing space side of the flexible lock arm in the one connector housing, the resilient contact pieces being displaced in accordance with displacement of the flexible lock arm; and a pair of connection sensing pin-type terminal fittings arranged so as to confront the short-circuiting contact member in the other connector housing, wherein when the pair of connector housings are connected incompletely, the flexible lock arm is displaced to displace the resilient contact pieces so as to break contact of the resilient contact pieces with the connection sensing pin-type terminal fittings.

Abstract: A short-circuit contact is doubly locked by providing a locking protrusion at a cover plate of the short-circuit contact mounted on one connector housing, engaging the locking protrusion with a locking recess provided at a contact-support chamber of the one connector housing to primarily lock the short-circuit contact, engaging the insert locking piece into a locking piece insertion hole provided at the one connector housing to engage a locking protrusion of the insert locking piece with the base plate of the short-circuit contact, thereby secondarily locking the short-circuit contact.

Abstract: A connector includesvone connector housing having a flexible lock arm, other connector housing having an engagement portion corresponding to the flexible lock arm, a short-circuiting contact member having resilient contact pieces, the short-circuiting contact member arranged on a displacement allowing space side of the flexible lock arm in the one connector housing, the resilient contact pieces being displaced in accordance with displacement of the flexible lock arm; and a pair of connection sensing pin-type terminal fittings arranged so as to confront the short-circuiting contact member in the other connector housing, wherein when the pair of connector housings are connected incompletely, the flexible lock arm is displaced to displace the resilient contact pieces so as to break contact of the resilient contact pieces with the connection sensing pin-type terminal fittings.

Abstract: A connector checking apparatus includes a connector checking device having a main body operable by a lever to move toward a connector. The connector checking device also has a connector support. Detection pins are slideably disposed within the main body and are connected to checking terminals. The detection pins have a conductive contact face and detection fingers on a detection piece. Upon insertion of the detection pins into the connector, complete insertion of the terminals within the terminal receiving cavities of the connector permits contact between the conductive face and an end of the terminal C. The connector has cantilever resilient supporting pieces which include a locking projection 14a. The device can detect whether or not the connector checking device A is completely engaged with the connector.

Abstract: A microwave oven with an invertor control power source produces a microwave by the use of the magnetron in relation to the high frequency power generated by the invertor control power source. The heat sensitive ferreit beads provided on the lead wire for transmitting the high frequency power to the magnetron changes the inductance of the wire from the high level to the low level at around a threshold temperature lower than the working equilibrium temperature of the magnetron. The cathode filament current remains within the allowable range, and the moding of the magnetron is prevented. The magnetron can operate in a long life time.