US3688063A - Crash sensing switch - Google Patents

Crash sensing switch Download PDF

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Publication number
US3688063A
US3688063A US117560A US3688063DA US3688063A US 3688063 A US3688063 A US 3688063A US 117560 A US117560 A US 117560A US 3688063D A US3688063D A US 3688063DA US 3688063 A US3688063 A US 3688063A
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United States
Prior art keywords
band
rollers
roller
housing
contact
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Expired - Lifetime
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US117560A
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English (en)
Inventor
Lon E Bell
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TRW Technar Inc
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TRW Technar Inc
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P15/135—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by making use of contacts which are actuated by a movable inertial mass
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H35/00—Switches operated by change of a physical condition
    • H01H35/14—Switches operated by change of acceleration, e.g. by shock or vibration, inertia switch
    • H01H35/148—Switches operated by change of acceleration, e.g. by shock or vibration, inertia switch making use of a rolamite sensor

Definitions

  • ABSTRACT There is described a crash switch which can sense acceleration forces that operate for some period of time such that the product of acceleration and time exceeds some predetermined-level before the switch is actuated.
  • the switch utilizes rollers supported by a band wrapped around the rollers, in which movement of the rollers along the band actuates switch contacts to signal movement of the rollers over a predetermined distance.
  • change in the center of gravity of the rollers is used to shift the direction of maximum sensitivity to the accelerating force.
  • a single calibration adjustment by shifting the initial position of the rollers, controls both the level of acceleration force required to move the rollers and the acceleration-time product level required to trigger the switch to the nominal design levels.
  • This invention relates to acceleration responsive switching devices, and more particularly, is concerned with a switching device which is triggered in response to an acceleration force supplied for a predetermined period of time.
  • the active force on the accelerometer then drops off as the cosine of the angle, which means if the acceleration is at 90 to the axis, the component of force acting along the axis of the accelerometer drops off to zero.
  • the present invention is directed to an acceleration sensing device particularly suited for use as a crash switch which responds to both a particular acceleration level as well as a particular velocity level to actuate a switch.
  • a single calibration adjustment adjusts both the acceleration level and the velocity level of the device.
  • acceleration is sensed along two different axes.
  • the angle of maximum sensitivity is made adjustable by changing the center of gravity of the rollers.
  • FIGS. 1A and 1B show a sectional view of one form of a crash sensing switch of the present invention
  • FIG. 2 is a plan view of the flexible band used in the crash sensing switch of FIG. 1A and 13;
  • FIGS. 3, 4, 5 and 6 are used in explaining the calibration technique of the present invention.
  • FIGS. 7A and 7B show an alternative crash switch design according to the present invention which has a broad angle of response
  • FIG. 9 is a modified form of the crash sensing switch of FIGS. 7A and 7B.
  • FIG. 10 is a diagram useful in understanding the switch design of FIG. 9
  • FIG. 1 there is shown a crash switch incorporating a regular rolamite device such as described in Research Report SC-RR67-656, published by the National Bureau of Standards, entitled Rolamite: A New Mechanical Design Concept by D. F. Wilkes.
  • the crash switch comprises a pair of cylindrical rollers 10 and 12 positioned within a molded housing 14.
  • the molded housing provides two flat parallel surfaces 16 and 18 which are spaced apart a distance slightly greater than the diameterof the rollers.
  • the surface 18 is provided by a shelf 19 integrally molded as part of the housing.
  • the rollers are supported between the two parallel surfaces by a flexible spring band 20 made of beryllium-copper or other suitable flat spring material.
  • the band is anchored to the housing 14 at the left-hand end of the upper parallel surface 16 by means of studs 22.
  • the band extends around the roller 10 and then around the roller 12 and back along the lower parallel surface 18.
  • the other end of the band extends beyond the end of the shelf 19 in the housing and terminates adjacent a two-pole switch mounted within the housing.
  • the switch comprises an upper lug 30 which supports a movable contact 32 positioned on the end of a cantilever spring 34 attached to the lug 30.
  • the lug provides an electrical terminal by extending through the wall of the housing to provide an external connection.
  • a lug 36 supports one fixed contact 38 while a lug 40 supports a second fixed contact 42 on either side of the movable contact 32.
  • the lugs 36 and 40 extend through and are supported by the housing 14 to provide external electrical connections to the fixed contacts of the switch.
  • the band 20 is linked to the movable contact 32 by a spring element 46, which preferably is in the form of an inverted V with one end booking through a hole in the end of the band and the other end hooking through a hole in the cantilever spring 34.
  • the cantilever spring 34 and spring element 46 combine to maintain tension on the band sufficient to hold the roller 10 firmly against the upper surface 16.
  • the band 20, in a manner hereinafter described in detail, as a result of this tension produces a net force on the rollers urging them to the left, as viewed in the drawing.
  • FIG. 1A shows the rollers in FIG. 1A in the normal position in which the roller 12 and the surrounding band 20 are against an adjustable stop provided by a screw 50 extending through the wall of the housing. This screw provides a means of calibrating the device in the manner described below.
  • the switch has contacts 32 and 42 closed.
  • FIG. 1B shows the condition of the rollers as they are moved to the right relative to the housing to a position where the roller 12 drops off the end of the shelf 19. In this position, the roller 12 forces the band downwardly against a spring-loaded re-set member indicated generally at 52.
  • the re-set member 52 includes a re-set button 54 which projects through the wall of the housing 14.
  • a spring member 56 mounted on the re-set member 52 engages the inside of the housing and urges the re-set member 52 in a direction toward the rollers.
  • the strength of the spring 56 is not sufficiently strong to overcome the downward force of the roller 12 when it drops off the edge of the shelf 19.
  • the re-set button 54 on the outside of the housing 14 the re-set member 52 engages the band 20 and roller 12, forcing the roller 12 upwardly back onto the shelf 19, permitting the rollers to return to theposition illustrated in FIG. 1A.
  • the band 20 is designed to produce a net force on the rollers and 12 tending to move the rollers against the adjustable screw 50. This force is produced by the band under tension by providing a cutout in the band in the manner shown in FIG. 2. It is a well known property of the rolamite that a net force is produced by the band by the difference in the spring stiffness at the point where the band leaves the roller 10 and the point where the band leaves the roller 12.
  • One way of reducing the stiffness of the spring band is to reduce its effective width by providing a cutout in the band.
  • the cutout as shown in FIG. 2, must extend for a sufiicient distance along the length of the band so that the tangent point between the upper roller 10 and the band, as indicated at A in FIG.
  • the crash switch can be made to respond to any desired level of acceleration of the housing 14. This level is referred to as the g-level of the switch.
  • One of the significant features of the switch device of FIG. I for use as a crash sensing switch is that not only must the acceleration of the housing exceed some predetermined g-level before the rollers will begin to move, but this acceleration must be sustained for a sufficient length of time for the rollers to move from their initial position against the adjusting screw 50 to the point where the roller 12 drops off the end of the shelf 19 so as to actuate the switch.
  • the device By controlling the distance that the rollers have to move, the device must experience a certain change in velocity before the switch is actuated.
  • This level referred to as the acceleration-time product level or 31 level, is therefore a function of the difference in the stiffness of the band at point A and point B and the distance the rollers must move in going from point A to point A.
  • the g-level is determined by the difference in width of the band at point A and point B, i.e., the glevel is proportional to the width of the cutout.
  • the 31 level of the switch is therefore proportional to the area of the cutout, i.e., the width w times length L.
  • w and L can be very accurately controlled.
  • the thinner the band the lower the g-level and therefore the g1 level of the device.
  • the thicker the band the greater is the g-level and therefore the g! level of the device.
  • the effective stiffness of the band may vary due to normal manufacturing tolerances, some means must be provided to correct for such variations so that the switch unit can be accurately calibrated to the nominal g-level and g't level.
  • a calibration arrangement is provided by which merely changing the effective value of the length L it is possible to control both the glevel and the g't level so as to compensate for variations in the stiffness of the band.
  • the stiffness factor of band materials tends to vary anywhere over the limits from the factor threequarters to a factor of four-thirds.
  • a g-level and g-t level corresponding to a nominal stiffness factor of 1 can then be achieved by providing a cutout as shown in FIG. 6 which includes a uniform cutout width W, from s to s and then is tapered outwardly to some maximum width at 0.
  • the correct g.t level is also achieved.
  • the roller' is positioned at 0 in FIG. 6, where the cutout width is W 4 and the cutout area is arranged to equal 40.
  • This provides the proper g-level and 3-: level for a band having a stiffness factor of three-quarters.
  • the force F produced by the band for a given difference in the effective width Aw of the band at the two tangent points is given by the expression where E is the plate modulus of the band material, t is the band thickness, and d is the diameter of the rollers.
  • effective width is meant the total width of material.
  • the acceleration g required to move the rollers is selected for the particular application. This is the g-level of the crash unit. Selecting the minimum thickness within the tolerance range of the band, A w for the point s can be established from the above relation, using Newtons Second Law g(s) F/ W 2 where W is the weight of the two rollers.
  • the switch unit of FIGS. 1A and 18 provides a highly sensitive switch for sensing accelerations which exceed a particular'g-level and are of sufiicient duration to exceed a particular g1 level
  • the device only responds to the component of acceleration of the device which is in a direction parallel to the direction in which the rollers move. As the angle of acceleration deviates from this direction, this component of acceleration drops off as the cosine of the angle.
  • the sensitivity of the device drops off according to the cosine function as the direction in which the accelerating force applied to the device changes relative to the longitudinal axis of the device. A force normal to' the direction of roller movement has no effect.
  • FIGS. 7A and 78 A device providing an extended angular range of sensitivity is shown in FIGS. 7A and 78.
  • FIG. 7A shows the device in its initial condition and
  • FIG. 7B shows the same device with the switch triggered by exposing the device to a particular g't level.
  • the device of FIG. 7A includes a housing indicated generally at 70.
  • the housing is molded in plastic, for example, and has a back wall 72 and outer side walls 74 extending on four sides. Within the housing are a pair of integrally molded guide members 76 and 78 providing flat, smooth, slightly convex guide surfaces 80 and 82, respectively.
  • a pair of rollers 84 and 86 are held in rolling relationship to the guides 76 and 78, respectively, by a single band 88.
  • the band is anchored at one end by a pin 90 to the guide member 76.
  • the band extends in a loop around the roller 84 and then passes through a gap 92 between the adjacent ends of the guide member 76 and 78 onto the guide surface 82.
  • the band passes over the guide surface 82 and forms a loop around the roller 86.
  • the band 88 then passes from the end of the guide member 78 to a mounting bracket 94 in the form of a stiff cantilever spring.
  • the band 88 passes around the outer end of the supporting bracket 94 and is pinned to the bracket 94 by a rivet 96 or other suitable holding means.
  • the bracket 94 is securely supported to the housing 70 by a pair of lugs 98 which clamp the bracket 94.
  • the cantilever spring effect of the bracket 94 places the band 88 under tension. If the band 88 should break, the bracket 94 springs over against a contact 100.
  • the bracket 94 and the contact 100 extend outside of the housing to provide a pair of electrical terminals 102 and 104.
  • the shape of the band is shown in FIG. 8.
  • the band includes an end portion where pins 90 anchor the band to the guide member 76.
  • the band is provided with a cutout region extending from A to A. The length of this cutout region is slightly in excess of the maximum distance of the travel of the roller 84 along the surface 80.
  • the band is provided with a reduced cross section from C to C, which is narrow enough to pass through the cutout region A-A' so that the band can be looped" tout region BB. Again the distance BB along the band, as shown in FIG. 8, corresponds to the circumference of the roller 86.
  • the contact member 114 is also in the form of a cantilever spring which is electrically connected to the external terminal 112. Thus movement of the roller 86 against the contact 114 completes an electrical circuit between the terminals 102 and 112. Position of the rollers 84 and 86 when they are moved against the contacts 110 and 114 is illustrated in FIG. 7B.
  • the crash switch Since the crash switch is normally mounted so that the force of gravity is perpendicular to the plane of the paper as the device is viewed in FIGS. 7A and 73, it is necessary to support the rollers 84 and 86 against movement due to the force of gravity. This is accomplished by securing the band 88 directly to the rollers 84 and 86 by pins, as indicated at 116. While two pins for each roller have been shown in the figure, it will be understood that the band can be cemented, brazed, or otherwise secured to the roller within the are between the two pin positions shown. Within this arc, the band always remains in contact with the roller over the full distance of movement of the roller between the stop and the contact member. Thus the rollers are supported by the band, the tension in the band being sufficient to suspend the rollers and to hold the band in contact with the uide surfaces 80 and 82.
  • the calibration technique described above is applicable to the arrangement of FIGS. 7A and 7B by providing the cutout regions with the proper shape and making the positions of the stop members 106 and 108 adjustable from outside of the housing.
  • the device can be calibrated to the nominal g-level and g1 level.
  • One way of providing the correct variation in band width is shown in FIG. 8 at 117 and 119.
  • the direction of maximum sensitivity for the roller 84 is in a direction substantially parallel to the guide surface 80.
  • the direction of sensitivity of the roller 86 is in a direction substantially parallel to the guide surface 82.
  • FIG. 9 A simple and effective way to shift the angles of sensitivity of the unit of FIG. 7 is shown in FIG. 9.
  • the unit of FIG. 9 is basically identical to that described above in connection with FIGS. 7A and 7B.
  • the rollers 84 and 86 have holes drilled in the rollers, as indicated at and 122, respectively. The holes are drilled off center so as to shift the center of gravity c.g. off the axis of revolution of the rollers.
  • the effect of shifting the center of gravity is to shift the angle of maximum sensitivity of each of the rollers to any acceleration forces applied to 'the housing 70.
  • the effect of shifting the center of dicular to the plane on which the roller is moving has no effect on the acceleration of the roller.
  • the center of gravity moves in a circular path as the roller moves.
  • the direction of maximum sensitivity to an external force is always in a direction perpendicular to the line extending between the tangent point of the roller to the guide surface and the point at which the center of gravity is located.
  • the larger the distance between the center of gravity and the center of rotation of the roller the greater the angle of the direction of maximum sensitivity can be shifted. From FIG.
  • a crash switch comprising a housing having an interior chamber, the chamber having first and second parallel guide surfaces, said second surface terminating at one end at an intermediate point within the chamber, a pair of cylindrical rollers, the diameters of the rollers being less than the normal distance between the first and second surfaces but greater than half said normal distance, a flexible spring band anchored at one end to the housing adjacent one end of the first surface, the band passing around a portion of each of the rollers in a substantially S-shaped path between the two surfaces, the other end of the band extending beyond said one end of the second surface such that movement of the rollers along the band extends from between the two parallel surfaces to a position beyond said one end of the second surface, spring means connected between said other end of the bandand the housing for imparting tension to the band, and a re-set plunger extending into the chamber adjacent said one end of the second surface, the plunger having a portion movable toward and into engagementwith the band for urging the band in a direction toward the first surface when the position of the rollers is beyond said
  • said spring means includes a movable switch contact, and at least one fixed contact mounted within the housing, the movable contact being urged into and out of contact with said fixed contact by movement of the associated end of the band.
  • Apparatus as defined in claim 6 further including adjustable stop means for adjusting the initial position of the rollers over a range of positions to change the difference in width of the two tangent points for the initial position of the rollers.
  • G;, f: g(s) ds where s .-s,, is the minimum distance of the movement of the tangent point along the band for the nominal design g-t level of the switch.
  • An omnidirectional crash sensor comprising: a housing, means within the housing defining first'and second surfaces, a pair of rollers, a spring band looping completely around each of the rollers and along the two surfaces, means for holding the band under tenfirst and second surfaces are positioned at a substantial angle to each other.
  • Apparatus as defined in claim 11 comprising a spring member anchored to the housing and secured to the band to exert a tension force on the band, and an electrical contact mounted'in the housing adjacent to but spaced from the spring member, the spring member being positioned to engage the contact to complete an electrical current path in the absence of the restraining action of the band.
  • Apparatus comprising means defining a convexly curved surface, a cylindrical roller, a band of spring material extending in a closed loop around the roller, and means secured to opposite ends of the band for holding the band under tension against the curved surface, the band having a slot extending along a portion of its length and reduced width along a portion of its length, the reduced width portion passing through the slot to form the closed loop extending around the roller, the band having a different spring stiffness in the slotted portion and the reduced width portion to provide a net force on the roller urging the roller in one direction along the curved surface.
  • the apparatus of claim 16 further including electrical contact means positioned adjacent the curved surface, the contact means being actuated by movement of the roller to make and break an electrical current path.
  • a switch device for sensing acceleration forces comprising housing means having a pair of spaced apart parallel guide surfaces, a flexible spring band, a pair of rollers each having a diameter less than the spacing normally positioned between said guide surfaces but greater than half said spacing, the band being secured to the housing means at a first end against one guide surface and extending in an S-shaped path around the two rollers into contact with the other guide surface, said other guide surface terminating in a ledge, a second end of the band extending beyond said ledge, switch means including a movable contact and at least one fixed contact, said switch means also including spring means urging the movable contact into engagement with the fixed contact, and tension spring means operatively connecting said second end of the band to the movable contact for applying tension to the band,
  • the tension spring means being sufficiently strong to pull the movable contact away from the fixed contact thereby opening the switch means when both rollers are between the guide surfaces, the rollers being movable in rolling contact with the band to a position beyond the ledge in which the band is no longer in contact with said other guide surface, permitting one of the rollers to be moved away from the one guide surface by the tension in the band, the movement of the oneroller reducing the tension in said tension spring means and permitting the movable contact to move against the the band toward said-one guide surface to reposition the rollers between the guide surfaces.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Switches Operated By Changes In Physical Conditions (AREA)
  • Push-Button Switches (AREA)
  • A Measuring Device Byusing Mechanical Method (AREA)
US117560A 1971-02-22 1971-02-22 Crash sensing switch Expired - Lifetime US3688063A (en)

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US11756071A 1971-02-22 1971-02-22

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US (1) US3688063A (sv)
BR (1) BR7200964D0 (sv)
CA (1) CA950011A (sv)
DE (1) DE2206813A1 (sv)
FR (1) FR2126292B1 (sv)
GB (2) GB1386423A (sv)
IT (1) IT949164B (sv)
SE (3) SE383800B (sv)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4005298A (en) * 1975-05-19 1977-01-25 Esterline Electronics Corporation Electrically conductive moveable support member for use in electrical switches
US4167276A (en) * 1976-12-17 1979-09-11 Allied Chemical Corporation Self-contained air bag system
US4594485A (en) * 1985-04-04 1986-06-10 Brown Jr Milton F Impact sensor
US4857680A (en) * 1988-12-22 1989-08-15 Ford Motor Company Acceleration sensor
EP0422819A1 (en) * 1989-10-10 1991-04-17 Trw Technar Inc. Rolamite sensor
US5198740A (en) * 1989-10-04 1993-03-30 University Of Utah Research Foundation Sliding contact mechanical/electrical displacement transducer
US5272293A (en) * 1992-10-29 1993-12-21 The United States Of America As Represented By The United States Department Of Energy Rolamite acceleration sensor
US5302886A (en) * 1989-10-04 1994-04-12 University Of Utah Research Foundation Mechanical/electrical displacement transducer
US5457368A (en) * 1993-03-09 1995-10-10 University Of Utah Research Foundation Mechanical/electrical displacement transducer
US5462363A (en) * 1994-07-21 1995-10-31 Brinkman; Erik J. Scroller roller band device
US6039075A (en) * 1997-06-12 2000-03-21 Sarco Lc Band controlled valve/actuator

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3812726A (en) * 1972-09-28 1974-05-28 Technar Inc Velocity responsive apparatus
DE2962304D1 (en) * 1978-05-12 1982-04-29 Inertia Switch Ltd An inertia switch device
GB8314801D0 (en) * 1983-05-27 1983-07-06 Minnesota Mining & Mfg Electrical switch
US4819960A (en) * 1986-11-21 1989-04-11 Breed Automotive Technology, Inc. Angled vehicle crash sensor
FR2628887B1 (fr) * 1988-03-17 1990-04-13 Geiszt Andreas Dispositif de coupe-circuit automatique pour vehicules en cas de choc
GB2228828B (en) * 1989-01-19 1992-09-02 Inertia Switch Ltd Inertia sensor assembly
DE3908368A1 (de) * 1989-03-15 1990-09-20 Bayerische Motoren Werke Ag Beschleunigungssensor
US5031931A (en) * 1989-12-06 1991-07-16 Breed Automotive Corporation Velocity change sensor with spring bias
SE513091C2 (sv) * 1989-10-06 2000-07-03 Breed Automotive Tech Accelerometer för avkänning av hastighetsförändringar hos ett fordon

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3452175A (en) * 1967-05-29 1969-06-24 Atomic Energy Commission Roller-band devices
US3488098A (en) * 1968-03-26 1970-01-06 Teletype Corp Motion translating device
US3567881A (en) * 1969-12-10 1971-03-02 Atomic Energy Commission Roller-band inertial switch

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3452175A (en) * 1967-05-29 1969-06-24 Atomic Energy Commission Roller-band devices
US3488098A (en) * 1968-03-26 1970-01-06 Teletype Corp Motion translating device
US3567881A (en) * 1969-12-10 1971-03-02 Atomic Energy Commission Roller-band inertial switch

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4005298A (en) * 1975-05-19 1977-01-25 Esterline Electronics Corporation Electrically conductive moveable support member for use in electrical switches
US4167276A (en) * 1976-12-17 1979-09-11 Allied Chemical Corporation Self-contained air bag system
US4594485A (en) * 1985-04-04 1986-06-10 Brown Jr Milton F Impact sensor
US4857680A (en) * 1988-12-22 1989-08-15 Ford Motor Company Acceleration sensor
US5394070A (en) * 1989-10-04 1995-02-28 University Of Utah Research Foundation Sliding contact mechanical/electrical displacement transducer
US5198740A (en) * 1989-10-04 1993-03-30 University Of Utah Research Foundation Sliding contact mechanical/electrical displacement transducer
US5557185A (en) * 1989-10-04 1996-09-17 University Of Utah Research Foundation Mechanical/electrical displacement transducer
US5302886A (en) * 1989-10-04 1994-04-12 University Of Utah Research Foundation Mechanical/electrical displacement transducer
EP0422819A1 (en) * 1989-10-10 1991-04-17 Trw Technar Inc. Rolamite sensor
US5272293A (en) * 1992-10-29 1993-12-21 The United States Of America As Represented By The United States Department Of Energy Rolamite acceleration sensor
US5457368A (en) * 1993-03-09 1995-10-10 University Of Utah Research Foundation Mechanical/electrical displacement transducer
US5462363A (en) * 1994-07-21 1995-10-31 Brinkman; Erik J. Scroller roller band device
US6039075A (en) * 1997-06-12 2000-03-21 Sarco Lc Band controlled valve/actuator
US6173641B1 (en) 1997-06-12 2001-01-16 Sarcos, L.C. Band controlled valve/actuator
US6173640B1 (en) 1997-06-12 2001-01-16 Sarcos, L.C. Band controlled valve/actuator
US6196111B1 (en) 1997-06-12 2001-03-06 Sarcos, L.C. Band controlled valve/actuator
US6220145B1 (en) 1997-06-12 2001-04-24 Sarcos, Inc. Band controlled valve/actuator
US6253659B1 (en) 1997-06-12 2001-07-03 Sarcos Lc Band controlled valve/actuator
US6273137B1 (en) 1997-06-12 2001-08-14 Sarcos, Inc. Band controlled valve/actuator

Also Published As

Publication number Publication date
SE396158B (sv) 1977-09-05
FR2126292A1 (sv) 1972-10-06
CA950011A (en) 1974-06-25
IT949164B (it) 1973-06-11
FR2126292B1 (sv) 1974-12-13
SE7412514L (sv) 1974-10-04
GB1386421A (en) 1975-03-05
GB1386423A (en) 1975-03-05
SE383800B (sv) 1976-03-29
SE396159B (sv) 1977-09-05
DE2206813A1 (de) 1972-08-31
SE7412513L (sv) 1974-10-04
BR7200964D0 (pt) 1973-06-07

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