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US 4,891,987 AGranted
Magnetic linkage for bourdon tube gauges
OwnerWilliam E. Stockton, Harold E. Stocktoninventors
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OwnerWilliam E. Stockton, Harold E. Stocktoninventors
Estimating the term…
A Bourdon tube pressure gauge has a movement amplifying mechanism comprising a pinion of segment shaped permanent bar magnets extending radially and terminating at a circular edge magnetically driven by a pivotally mounted rack segment having an arcuate band of permanent bar magnets arranged in parallel alignment with polar axes extending radially of the rack and transversely of the band. One of the poles of each of the magnets of the band is located along a driving arcuate edge thereof which faces and magnetically drives the circular edge of the pinion by magnetic attraction of opposite poles. The polarity of adjacent magnets on both the pinion and rack segment is reversed providing alternate N and S poles around the pinion circular edge and along the driving edge of the band, respectively. In one form of movement, the rack segment is formed with an opening and the driving arcuate edge faces the opening in which the pinion is positioned for operative magnetic engagement between the band and pinion. In another form of movement, the pinion is positioned radially beyond the rack segment. The movement is housed in a rear compartment of the gauge which is lined with a magnetic flux barrier material.
A movement amplifying mechanism for converting a relatively short radial movement of the free end of a pressure gauge Bourdon tube to the rotary motion of a shaft on which a pointer is mounted for indicating pressure values on a circular dial, said movement amplifying mechanism comprising a rack segment pivotally mounted for acute angular movement and a pinion mounted on said shaft, a linkage connecting said Bourdon tube free end to said rack segment for pivoting the latter in response to said Bourdon tube free end movement, said rack segment having an arcuate band carrying magnetic means, said pinion having complementary magnetic means located for operative magnetic engagement with said rack segment magnetic means whereby pivotal rotation of said rack segment by said Bourdon tube free end movement rotates said pinion and shaft for predetermined pressure indication on said dial by said pointer.
A Bourdon tube pressure gauge comprising a tubular casing having a transverse wall dividing the casing into front and rear compartments, a Bourdon tube mounted at one end on said casing in said rear compartment and having an opposite free end adapted to move radially outwardly and inwardly a relatively short distance in response to pressure changes within said Bourdon tube, a movement amplifying mechanism located in said rear compartment for converting the relatively short radial movement of said Bourdon tube free end to the rotary motion of a shaft on which a pointer is mounted for indicating pressure values on a circular dial, said movement amplifying mechanism comprising a rack segment pivotally mounted for acute angular movement and a pinion mounted on said shaft, a linkage connecting said Bourdon tube free end to said rack segment for pivoting the latter in response to said Bourdon tube free end movement, said rack segment having an arcuate band carrying magnetic means, said pinion having complementary magnetic means located for operative magnetic engagement with said rack segment magnetic means whereby pivotal rotation of said rack segment by said Bourdon tube free end movement rotates said pinion and shaft for predetermined pressure indication on said dial by said pointer, a rear closure plate for said rear compartment mounted on said casing, said casing, Bourdon tube, rear closure plate, rack segment, linkage and shaft being made of a non-magnetic material, and said rear compartment having a lining of magnetic flux barrier material to isolate said arcuate band magnetic means and pinion complementary magnetic means from external magnetic interference.
Dependencies are inferred from the claim text.