US3728898A - Action unit for measuring devices - Google Patents

Action unit for measuring devices Download PDF

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Publication number
US3728898A
US3728898A US00130274A US3728898DA US3728898A US 3728898 A US3728898 A US 3728898A US 00130274 A US00130274 A US 00130274A US 3728898D A US3728898D A US 3728898DA US 3728898 A US3728898 A US 3728898A
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US
United States
Prior art keywords
intermediate member
diaphragm
leaf spring
spring
movement
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00130274A
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English (en)
Inventor
H Schlenker
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FA SCHLENKER H DT
SCHLENKER FA H
Original Assignee
SCHLENKER FA H
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Filing date
Publication date
Priority claimed from DE19702015449 external-priority patent/DE2015449C/de
Application filed by SCHLENKER FA H filed Critical SCHLENKER FA H
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Publication of US3728898A publication Critical patent/US3728898A/en
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Expired - Lifetime legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L7/00—Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00—Machine element or mechanism
    • Y10T74/18—Mechanical movements
    • Y10T74/18568—Reciprocating or oscillating to or from alternating rotary
    • Y10T74/18832—Reciprocating or oscillating to or from alternating rotary including flexible drive connector [e.g., belt, chain, strand, etc.]
    • Y10T74/18848—Reciprocating or oscillating to or from alternating rotary including flexible drive connector [e.g., belt, chain, strand, etc.] with pulley

Definitions

  • An action unit for a measuring device such as an aneroid barometer incorporates a U-shaped blade spring [30] Foreign Application P iorit D t one limb of which is fixed to an adjustable support while the other limb, which is longer than the first 1970 Germany 20 15 449'8 limb, provides a bearing surface for an intermediate member engaged by an actuator pin of the measuring 2? 313?
  • the actuator pin is disposed between the yoke 387 386A and the terminal edge of the longer limb of the blade 1 le 0 earc 74/89 2 g spring and the intermediate member bears on said terminal edge and on points between said edge and the yoke, and said intermediate member is extended to [56]
  • References Clted provide means for actuating an indicator through 21 UNITED STATES PATENTS movement-amplifying linkage system.
  • the invention relates to an action unit for an aneroid barometer.
  • Such devices embody a responder member such as an evacuated capsule having a pair of diaphragms secured to a carrier.
  • Such action units include a diaphragm pin extending substantially perpendicularly to the surface of one diaphragm and the movements of the pin are transmitted by one end of a transmission lever to an indicator while the other end of the lever is connected to a free limb of a bent U- shaped blade spring the center plane of which lying in the U-cross-sectional surface of the spring stands radial to the axis of the diaphragm pin with the yoke remote from this axis, and one limb of this spring is secured to the carrier whereas the free limb is in operative connection without play with the diaphragm pin by means of an intermediate member.
  • the free end of the U-shaped blade spring is bent outwardly parallel to the yoke and this bent part bears against a cross bearer under the pre-stress of the U-spring and the longitudinal direction of which coincides with the longitudinal direction of the bent edge and is screwed to the diaphragm pin.
  • the free edge of the bent part of the U-spring is radial to the axis of the diaphragm pin.
  • the U-spring has a relatively great width and its free limit is provided in its central region with a recess which surrounds the diaphragm pin.
  • the two diaphragms of the diaphragm capsule are forced apart so that the diaphragm capsule is under pre-stress.
  • the movement of the free edge of the bent part of the U-spring does not run exactly perpendicularly to the outer surface of the diaphragm, that is not parallel to the axis of the diaphragm pin, but describes an arc.
  • the whole U-spring is arranged on that side of the diaphragm capsule the diaphragm of which carries the diaphragm pin.
  • the length of the limb of the U-spring is less than the radius ofthe diaphragm capsule.
  • the limb length is greater than the radius of the barometer capsule, and the barometer capsule is surrounded on both sides by the limbs of the U-spring.
  • the diaphragm pin is provided with a cross bore which runs parallel to the yoke of the U-limb.
  • a short pin is disposed in this bore which rests in a corresponding depression of the free limb of the U-spring and which transmits the pr'e-stressing force of the U-spring to the diaphragm pin.
  • the object of the present invention is to increase the response or pressure sensitivity of such mechanisms, especially for barometers.
  • the free limb of the blade spring is longer than the spacing from the yoke to the pin axis and the intermediate member which lies on the one hand in a bearing element of the diaphragm pin and on the other hand bears on the free limb of the blade spring both in the region between the diaphragm pin axis and the blade spring yoke and also in the region externally of the diaphragm pin axis and the blade spring yoke.
  • the particular advantage of this arrangement lies in the fact that in this way it is possible to allow the diaphragm pin to execute a movement in the direction of its axis without disturbing transverse components. This has the advantageous result that the response or pressure sensitivity of a barometer orthe like constructed in this way is substantially improved.
  • a further advantage of an action unit according to the invention lies in the fact that the technical production and assembly expenditure is not increased in prac tice and that nevertheless by thenew arrangement of the force transmission from the diaphragm pin to the blade spring the desired course of movement and increased response and pressure sensitivity is attained.
  • the invention can for example be carried out in such manner that the diaphragm pin is provided with a radial bore the axis of which is disposed parallel to the outer surface of the diaphragm and perpendicularly to the yoke of the blade spring, that is in the longitudinal direction of the spring limb.
  • a pin inserted in a bore of the diaphragm pin then serves as the intermediate member which in some cases bears against embossings or with the interposition of support washers or the like against the blade spring limbs.
  • the desired course of movement of the diaphragm pin is attained by a suitable choice of the bearing points on the blade spring. The bearing points execute different movements according to their spacing from the yoke of the blade spring.
  • a pin is not used as the intermediate member but the intermediate member is of bent W-shape and the central portion ties in the bearing element of the diaphragm pin with its axis parallel to the length of the yoke.
  • This con structional form has the particular advantage that a U- spring an be used the length of which is not small compared with the limb length perpendicular to it.
  • the bent W-shaped intermediate member bears at least at four points on the free limb of the blade spring and ensures that the outer corners of the free blade spring limb are not substantially unloaded as compared with the central region. This way ensures that the free blade spring limb does not flex in a direction which runs parallel to the diaphragm pin axis.
  • the relatively large superficial engagement of the bent W-shaped intermediate member on the free limb of the blade spring ensures that the blade spring limb is not curved perpendicularly to the limb length.
  • the intermediate member bears at least at four points .on the free blade spring limb and therefore a relatively high friction to movements is to be expected, nevertheless a substantial increase in the response or pressure 'sensitivity of the device is quite unexpectedly obtained which demonstrates that known spring suspensions do not operate vertically to the diaphragm capsule.
  • a transmission lever is fitted to the free blade spring limb, for example riveted to it, which transmits the movement of the diaphragm pin or of the free blade spring limb to an indicator with a ratio corresponding to its length.
  • this transmission lever must always be arranged externally of the center of the blade spring since the diaphragm pin is arranged in the center region thereof.
  • the intermediate member embodies an extension which serves as a transmission lever.
  • this extension is used as a transmission lever.
  • This embodiment has on the one hand the advantage that a special fastening of the transmission lever to the U- spring is avoided.
  • This special fastening often effects a weakening of the spring limb (by riveting) or a local stiffening of the spring limb (for example by adhesive or by multi-point riveting).
  • the transmission lever does not influence the blade spring limb practically at all so far as, as is always assumed, the intermediate member is inherently sufficiently stiff flexurally. This stiffness is however practically always available since the forces to be transmitted to the indicator are relatively small because they only have to overcome the return force of a spiral or hair spring provided on the indicator shaft and the relatively small friction forces of the indicator.
  • the intermediate member can rest on the free limb of the blade spring with the interposition of support washers, small plates or the like.
  • the free limb of the blade spring is bent outwardly away from the U-section and the intermediate member lies directly on the terminal edge. Since the blade spring thickness is relatively small, the bearing operates in the manner of a knifeedge bearing; the intermediate member can therefore execute a tipping movement about this edge with very low friction.
  • the spacing from the diaphragm pin axis of the bearing point of the intermediate member on the terminal edge of the free limb of the blade spring, in the projection on the center plane of the U-cross-section, is less than the spacing from the diaphragm pin axis of the bearing point of the intermediate member on the free limb of the blade spring between the diaphragm pin axis and the yoke.
  • the ratio of these distances is then so chosen dependently on the spring dimensions and the spring constants that the desired movement of the portion of the intermediate member which transmits the blade spring force to the diaphragm pin, is obtained.
  • the diaphragm pin moves during air pressure changes practically exactly in the direction of its longitudinal axis and thus perpendicularly to the diaphragm surface.
  • the intermediate member is bent from a length of spring steel wire, although the spring properties of such wire are not involved.
  • a wire of circular cross-section is usually used but also other cross-sectional profiles are possible.
  • an intermediate member in one piece of plastics, for example as an injection moulding.
  • the production as an injection moulding has the particular advantage that the intermediate member can be easily produced with locally different cross-sections; in this way the cross-sections can be adapted to the particular loading or to the particular function.
  • the bearing surfaces on the blade spring limb may be made for example ball-shaped whereas the parts stressed in flexure have a corresponding U, l or other particularly flexure-stiff profile.
  • the bearing element of the diaphragm pin in which the intermediate member lies can be constructed for example as a knife edge element, that is it may have an approximately V-shaped outer surface shape. It is also possible to make the bearing element spherical and to provide the intermediate member at this point with a ball-socket-shaped projection whereby a free low-friction rocking on all sides is possible.
  • the wall of a cross bore through the diaphragm pin is used as the bearing element for the intermediate member. This is the simplest and most economical solution which meets all requirements.
  • the axis of the cross bore then runs parallel to the yoke length or the terminal edge of the free blade spring limb. Since in practice only movement of the intermediate member in the, bearing element tangential to its periphery occurs, such a cylindrical bearing element meets all requirements.
  • the fixed blade spring limb can surround the diaphragm capsule and be fastened to the side of the diaphragm capsule remote from the diaphragm pin to a support or casing.
  • a screw guided in the casing can then press against the fixed blade spring limb between the fastening point and the yoke of the blade spring.
  • the fixed blade spring limb is arranged on the same side of the diaphragm capsule as the free blade spring limb.
  • the fixed blade spring limb is secured to a bridge which is pivotal about an axis approximately parallel to the diaphragm and approximately perpendicular to the diaphragm pin axis.
  • the bridge is of approximately L-shape in plan with the pivot axis parallel to the longer limb of the L.
  • a screw fixed to the casing engages the end of the short limb of the L by adjustment of which the bridge is rotatable about its pivot axis.
  • FIG. 1 is a plan of a barometer system and action unit constructed according to the invention.
  • FIG. 2 is a side view in the direction of the arrow II of FIG. 1.
  • a base plate 1 embodies on one side opposed lugs 2 bent up from the plane of the base plate through 90, which run out into points.
  • a flat L-shaped carrier 3 rests on the points of the lugs 2 and is pivotal about the axis defined by the said points.
  • the carrier lies on the points of the lugs 2 in each case in the end region of the longer limb of the L.
  • the free end of the shorter limb of the L lies on a grub screw 4 which is screwed into a threaded bore traversing the base plate 1 approximately perpendicularly. By turning the grub screw 4 the carrier 3 can be rocked in for fine adjustment.
  • a u-shaped bent blade spring 5 is fixed to the long limb of the L of the carrier 3 by means of a clamp plate 6 being for example riveted, screwed or the like.
  • the blade spring 5 embodies a shorter fixed limb 7 and a longer free limb 8.
  • the end of the fixed limb 7 is secured to the carrier 3 by the clamp plate 6.
  • the blade spring 5 embodies a relatively great span in the direction transversely to the length of the limb. Preferably this length span of the blade spring 5 is greater than the length of the free limb 8.
  • the free end of the free limb 8 is bent out of the U-cross-section parallel to the yoke connecting the two limbs of the blade spring 5; the resulting narrow edge 9 stiffens the free limb 8 in reference to flexure moments which load it transversely to the length of the limb.
  • the base plate embodies a bore somewhat offset laterally to the center between the two lugs 2, through which is inserted a fastening pin for a diaphragm capsule 10 and is fastened by means of a nut 11 screwed into position, or the fastening may be by a set screw.
  • the diaphragm capsule responds to changes of atmospheric pressure and is formed by two diaphragms.
  • the diaphragm remote from the base plate 1 carries centrally a diaphragm pin 12 the axis of which is perpendicular to the outer surface of the diaphragm.
  • the length of the lugs 2 is greater than the height of the diaphragm capsule 10 so that the carrier 3 and the blade spring 5 are located on the side of the diaphragm capsule remote from the base plate 1.
  • the line connecting the tips of the two lugs 2 passes close to the diaphragm pin 12.
  • the diaphragm pin 12 is provided in the neighborhood of its free end with a cross bore 13 the axis of which is approximately parallel to the line connecting the tips of the two lugs 2 or parallel to the length of the edge 9.
  • the center part of a W-shaped bent spring steel wire member is inserted through the transverse bore 3 and this member serves as an intermediate member 14 which produces an operative connection between the diaphragm pin 12 and the blade spring 5.
  • One end portion of the W-shaped intermediate member is provided with an extension 15 which serves as a transmission lever for the measuring movement, and functions as a movement transmitting linkage system.
  • the intermediate member 14 bears at least at four points on the blade spring; two of these bearing points are located in the region of the two loop curves 16 of the W and the other two are formed by the bearing of the terminal sections of the W on the free corner of the edge 9.
  • the center portion 17 of the intermediate member 14 bears on the wall of the cross bore 13 under the action of the pre-stressed blade spring 5.
  • the center portion 17 can execute a rocking movement and/or a small rolling movement in the cross bore 13.
  • the spacing of the bearing point of the intermediate member 14 on the edge 9 is less distant from the bearing point of the center portion 17 on the cross bore 13 than the bearing point at which the intermediate member 14 rests on the blade spring 5 in the region of the base curve 16.
  • the arrangement is symmetrical to the center plane of the U-section of the blade spring 5 in which also lies the longitudinal axis of the diaphragm pin 12.
  • the different spacings of the bearing points of the pivot axis of the intermediate member 14 provide that for pressure changes the diaphragm pin 12 is moved almost exactly in its axial direction and practically no transverse movement components are present.
  • the base plate 1 embodies a projection 18 on the side remote from the line connecting the two lugs 2, which is likewise provided with two mutually opposite lugs 19 bent at out of the plane of the base plate.
  • Coaxial bearing grub screws 20 are screwed into the two lugs 19.
  • a rocking bracket 21 produced in the form of a sheet pressing is pivoted on the tips of the bearing grub screw, and one limb of a U-shaped bent adjuster spring 22 is fastened to the bracket 21.
  • the spacing of the other limb of the adjuster spring from the rocking bracket 21 is adjustable by means of a screw 23 screwing in the said bracket.
  • the extension 15 of the intermediate member 14 is bent twice and the free end of the extension 15 lies on the free end of the adjuster spring 22. By turning the screw 23 the position of the bearing point of the end of the extension 15 on the adjuster spring 22 can be varied to vary the transmission ratio of the movement of the extension 15 to the rocking movement of the rocking bracket 21.
  • the rocking bracket 21 carries a radially projecting arm 24 to which the pull rod 25 is pivotally connected and to the other end of which a chain or cord 26 is fitted which extends around an indicator spindle 27.
  • the indicator spindle 27 is supported on a carrier arm 28 and a counter plate 30 opposite the carrier arm and connected to it by two supports 29.
  • the carrier arm 28 is arranged about parallel to the base plate 1 and secured to a pillar 31 fitted on the base plate 1 by means of a clamp screw 32.
  • the indicator spindle 27 carries an indicator 33 which moves over a scale, not shown.
  • a spiral spring or hair spring 34 is secured at its inner end to the indicator spindle 27 and its outer end is fixed to one of the supports 29.
  • the spiral or hair spring 34 provides a return force which holds the lever mechanism without play in the position obtained by cooperation of the diaphragm capsule l0 and the blade spring 5.
  • the mode of operation of the arrangement of this invention is as follows:
  • the evacuated diaphragm capsule or bellows 10 is biased by the U-shaped spring 5, the free leg 8 of which exerts a pulling force on the bellows canying the diaphragm pin 12, via the central section 17 of the intermediate member 14 supported in the bore 13 of the diaphragm pin 12.
  • the diaphragm pin 12 moves in the direction of its axis toward the carrier 1 or away therefrom, and the spring 5 is more strongly tensioned, or relaxed.
  • This movement is transmitted, by the transmission lever 15, to the pivotably mounted swivel bracket 21.
  • the pivotal motion of the swivel bracket 21 is transmitted, via the pull rod 25 and the chain or cord 26 to the indicator spindle 27 and thus to the pointer 33.
  • the invention is not limited to the constructional example shown but changes are possible without departing from the framework of the invention.
  • the arrangement described for the widest range of measuring devices in which it happens that the movement of a measuring element subjected to the action of an external pre-stress should have no disturbing cross components.
  • the intermediate member is not limited to the constructional embodiment described. It is for example possible for the cross bore 13 to be turned through 90 about the longitudinal axis of the diaphragm pin 12 and to effect the force transmission by means of a in bearing at two points on the blade spring 5.
  • the free limb 8 of the blade spring 5 would in this case embody an aperture through which the diaphragm pin 12 projects.
  • the pin then rests on the free limb 8 of the blade spring on both sides of the aperture.
  • the extension 15 can be directly attached to the pin, it can also in known manner be secured to the blade spring 5.
  • The'essential feature of the invention consists in the fact that by the multiple bearing of the intermediate member on the blade spring, movement of the diaphragm pin 12 or the like in the axial direction of this pin can be secured.
  • a movement for a measuring device comprising a support member, a diaphragm capsule having one surface attached to said support member, a diaphragm pin mounted transversely on the opposite surface of said diaphragm capsule, a transmission lever extending from an intermediate other le of said U-shaped leaf sprin extending past the diap agm pm axis, said mterme rate member extending through a bore in said diaphragm pin and contacting said other leg of said U-shaped leaf spring at two distinct bearing points, one of said bearing points being in the zone between said diaphragm pin axis and the base of said U-shaped leaf spring and the other bearing point being outside this zone, said intermediate member being spaced from said U-shaped leaf spring between said bearing points.
  • said operating means includes a bridge pivotable on said support member about an axis approximately perpendicular to said diaphragm pin axis, said bridge being connected to said transmission lever and said pointer to transfer movements of said transmission lever to said pointer.
  • said support member is provided with a pair of spaced lugs disposed on a line passing closely adjacent said diaphragm pin, an L-shaped carrier member being supported on said spaced lugs and said one leg of said U- shaped leaf spring being attached to said carrier.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Fluid Pressure (AREA)
US00130274A 1970-04-01 1971-04-01 Action unit for measuring devices Expired - Lifetime US3728898A (en)

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Application Number Priority Date Filing Date Title
DE19702015449 DE2015449C (de) 1970-04-01 Meßgerät

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GB (1) GB1301977A (enExample)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4255970A (en) * 1978-12-13 1981-03-17 Pottelberg Gaston C Van Barometer mechanism

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1612344A (en) * 1925-05-26 1926-12-28 Taylor Instrument Co Aneroid barometer
US3397578A (en) * 1963-04-03 1968-08-20 Taylor Instrument Co Motion amplifying mechanism for pressure responsive instrument movement
US3451272A (en) * 1967-09-18 1969-06-24 Gen Time Corp Barometer movement
US3623051A (en) * 1970-06-12 1971-11-23 Weather Watch Instr Alarm barometer

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1612344A (en) * 1925-05-26 1926-12-28 Taylor Instrument Co Aneroid barometer
US3397578A (en) * 1963-04-03 1968-08-20 Taylor Instrument Co Motion amplifying mechanism for pressure responsive instrument movement
US3451272A (en) * 1967-09-18 1969-06-24 Gen Time Corp Barometer movement
US3623051A (en) * 1970-06-12 1971-11-23 Weather Watch Instr Alarm barometer

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4255970A (en) * 1978-12-13 1981-03-17 Pottelberg Gaston C Van Barometer mechanism

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Publication number Publication date
GB1301977A (enExample) 1973-01-04
DE2015449B2 (de) 1971-05-19
DE2015449A1 (enExample) 1971-05-19

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