초록 ▼

An electro-pneumatic transducer for converting an input current signal to a proportional output pressure signal is disclosed. The transducer includes housing means defining a chamber, the housing may be completely of magnetic material or may have a magnetic portion and a non-magnetic portion. The tr

An electro-pneumatic transducer for converting an input current signal to a proportional output pressure signal is disclosed. The transducer includes housing means defining a chamber, the housing may be completely of magnetic material or may have a magnetic portion and a non-magnetic portion. The transducer includes an input communicating with the chamber for supplying a fluid under pressure thereto and having a valve seat with a nozzle opening therethrough, that portion of the nozzle forming the valve seat being formed of non-magnetic material while the remainder of the housing is of magnetic material or the valve seat may also be of magnetic material. The transducer also includes an output communicating with the inlet for allowing fluid supplied by the inlet to flow to a control device. Disposed within the chamber is a membrane means in operative association with the nozzle opening in the valve seat for varying the fluid flow through the nozzle opening to thereby vary the fluid pressure at the output. The membrane also includes a magnetic portion and a non-magnetic or plastic portion. An electric coil is located within the chamber and surrounds a center post disposed within the chamber. Lastly, the transducer includes means for imparting a current signal to the electric coil to generate an electric field to magnetize the magnetic portions of the membrane and the housing, the degree of magnetization being proportional to the input current signal to position the membrane relative to the valve seat to thereby modulate the transducer output. Also disclosed are pneumatic and electronic control circuits for the transducer.

대표청구항 ▼

An electro-pneumatic transducer for converting an input current signal to a proportional output pressure signal characterized by its low power consumption, said transducer comprising: housing means and having magnetizable top and bottom sections, defining a chamber, the bottom section having a cente

An electro-pneumatic transducer for converting an input current signal to a proportional output pressure signal characterized by its low power consumption, said transducer comprising: housing means and having magnetizable top and bottom sections, defining a chamber, the bottom section having a center post extending into the chamber; said center post defining inlet means in the housing communicating with said chamber for supplying fluid under pressure thereto and having a valve seat with a nozzle opening therethrough; outlet means communicating with said inlet means for allowing fluid supplied by said inlet means to flow to a control device; flexible membrane means between the top and bottom sections of the housing means extending across the chamber in overlying relation to said nozzle opening and defining air gaps above and below said membrane and movable for varying the fluid flow through the nozzle opening to thereby vary the fluid pressure at the outlet means; said membrane means being essentially non-magnetic and having a magnetic portion adjacent the valve seat; electric coil means wound around the center post; and said coil means being operable upon a current signal being imparted thereto to generate a magnetic field to magnetize the magnetic portions of the membrane and the housing, the degree of magnetization being proportional to the input current signal to position the membrane relative to the valve seat proportional to the input signal, said magnetic portion of the membrane being positioned to cause the majority of the flux to pass through top of the housing, the air gap above said membrane, the magnetic portion of the membrane, and through the valve seat, whereby the transducer output may be carefully and accurately controlled by modulating the membrane between using a minimum of electrical energy.