Micro displacement force transducer
AssigneePanex Corporation
InventorLeroy C. Delatorre
Life of this patent
Estimating the term…
Abstract
A sensor system utilizing a bourdon tube to generate a force as a function of pressure to deflect a diaphragm in a capacitor device where the diaphragm varies capacitance values of the capacitor device as a function of the applied force. The capacitor device is an essentially integral circularly shaped construction of quartz material in which the diaphragm is attached to a tubular quartz member. A metal member having a similar coefficient of temperature expansion to the coefficient of the quartz is used to couple the diaphragm to the bourdon tube.
Claims25
A force sensitive capacitance device for developing capacitance values as a function of force applied to said device, said force sensitive capacitance device having a capacitor member with a micro-displacement range of movement for developing said capacitance values, said force sensitive device being disposed between a reference base support member and a force linkage member attached to said capacitor member,
- a pressure responsive member attached to said force linkage member, said pressure responsive member having a relatively large displacement range of movement as compared to the displacement range of movement of said capacitor member, said pressure responsive member being responsive to pressure to displace said force linkage means,
- said capacitor member being constructed from quartz and being cylindrically shaped about a central axis, said capacitance device further including cylindrically shaped base members constructed from quartz and disposed to either side of said capacitor member, a tubular boss member constructed from quartz and bonded to said capacitor member, said force linkage member being coupled to said boss member.
A transducer for providing capacitance measurements indicative of an applied force, comprising:
- a hollow resilient, elongated pressure member having at least one closed end, said pressure member having an interior and an exterior between which a pressure differential can be applied, said pressure member being constructed and having a nonsymmetrical configuration in cross-section and being arcuately curved so that it moves in response to variations in differential pressure,
- a force sensitive capacitance means for generating capacitance signals, said force sensitive capacitance means being connected between a base support member and a force linkage member, said force linkage member being coupled to the closed end of said pressure member so that force developed by movement of said pressure member can be applied to said capacitance means, said capacitance means having a diaphragm member constructed from quartz with sufficient stiffness to constrain movement of said pressure member so that movement of said diaphragm member is the basic measurement factor for pressure applied to said pressure member and movement of said pressure member is negligible, said diaphragm member being coupled to said force linkage member whereby the capacitance values of said capacitance means are principally dependent upon the elastic properties of said diaphragm member and the compression or tension force applied to said diaphragm member.
A transducer for providing capacitance measurements indicative of an applied force, comprising:
- a pressure member having an interior and an exterior between which a pressure differential can be applied, said pressure member being constructed so that it moves in response to variations in differential pressure,
- a force sensitive capacitance means for generating capacitance signals, said force sensitive capacitance means being connected between a base support member and a force linkage member, said force linkage member being coupled to said pressure member so that force developed by movement of said pressure member can be applied to said capacitance means, said capacitance means having a diaphragm member constructed from quartz with sufficient stiffness to constrain movement of said pressure member so that movement of said diaphragm member is the basic measurement factor for pressure applied to said pressure member and movement of said pressure member is negligible, said diaphragm member being coupled to said force linkage member whereby the capacitance values of said capacitance means are principally dependent upon the elastic properties of said diaphragm member and the compression or tension force applied to said diaphragm member.
A transducer for providing capacitance values indicative of an applied force, comprising:
- a base support member having a support surface and an opening to said support surface, said opening having a first axis,
- transducer means for providing capacitance values as a function of an applied force, said transducer means having an annular surface in contact with said support surface,
- said transducer means having a transducer axis along which a force may be applied to the transducer means, said transducer axis being aligned with said first axis,
- a force linkage member coupled to said transducer means and movable along said transducer axis, said linkage member having a transverse opening,
- a tubular support member for a bourdon tube, said tubular support member being attached to said base support member and having a transverse outer groove for receiving a portion of a bourdon tube member,
- a bourdon tube member having a closed end attached to said force linkage member and being arcuately curved to pass through said transverse opening in said force linkage member, and
- a cover member for clamping said bourdon tube member in said transverse outer groove, said cover member being attachable to said tubular support member.
A force sensitive capacitance device for developing capacitance values as a function of force applied to said device, said force sensitive capacitance device having a capacitor member with a micro-displacement range of movement for developing said capacitance value, said force sensitive device being disposed between a reference base support member and a force linkage member attached to said capacitor member,
- a pressure responsive member attached to said force linkage member, said pressure responsive member having a relatively large displacement range of movement as compared to the displacement range of movement of said capacitor member, said pressure responsive member being responsive to pressure to displace said force linkage means,
- said capacitor member being constructed from quartz and being cylindrically shaped about a central axis, said capacitance device further including at least one cylindrically shaped base member constructed from quartz and disposed to either side of said capacitor member, a tubular boss member constructed from quartz and bonded to said capacitor member, and said force linkage member being coupled to said boss member, and
- metallized surface means constructed and arranged on said capacitor member and at least one of said base members for developing capacitance values.
Dependencies are inferred from the claim text.