Push/pull Rod Patents (Class 200/538)
  • Patent number: 9299512
    Abstract: A device for switching and controlling electrical apparatus, has a guide bearing for creating haptics indicating the position of the device. The guide bearing has one bearing part constructed as a switch housing and one bearing part constructed as an actuating element. The guide bearing has a control path formed on one of the bearing parts and a rolling-body mount constructed on the other bearing part. A rolling body is held in the rolling-body mount. A haptic spring presses the rolling body onto the control path. The structure of this device is suitable for creating haptics, without the operational reliability and service life of the guide bearing being appreciably impaired.
    Type: Grant
    Filed: July 14, 2014
    Date of Patent: March 29, 2016
    Assignee: JOHNSON ELECTRIC S.A.
    Inventors: Gerhard Fangmann, Udo Balgheim, Martin Koepsell
  • Publication number: 20150123752
    Abstract: An electrical disconnect apparatus includes a housing having an interior and an exterior, first and second conductors extending from the exterior into the interior, a movable conductor, and an actuator assembly coupled to the housing. The movable conductor has a connected position in which the movable conductor electrically connects the first conductor and the second conductor, and a disconnected position in which the first conductor is electrically disconnected from the second conductor. The actuator assembly is adapted to move the movable conductor between the connected position and the disconnected position, and can be actuated manually or automatically.
    Type: Application
    Filed: November 1, 2013
    Publication date: May 7, 2015
    Applicant: Eaton Corporation
    Inventors: MARK A. FAULKNER, Jerry S. Wang
  • Patent number: 8976002
    Abstract: A universal remote control system is disclosed. The universal remote control includes a receiver that has a wireless signal receiver unit, an electric motor that drives a mechanical arm and a microprocessor. When the receiver receives a control signal from a wireless signal transmitter, the microprocessor will energize the motor which drives the mechanical arm toward a pushbutton switch of a controlled device, such as a garage door opener, and depresses the push button, therefore activating the garage door opener. A feedback signal, for example, from the mechanical arm or the motor, may be provided to the microprocessor to inform the microprocessor when the pushbutton switch is sufficiently depressed and is in an engaged state. When the switch is in the engaged state, the motor will reverse its direction, causing the mechanical arm to raise and move back to a standby position.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: March 10, 2015
    Inventors: Philip Yu Wing Tsui, Gallen Ka Leung Tsui
  • Patent number: 8822864
    Abstract: A switching apparatus for closing and/or opening an electric circuit. It has an actuating unit and a bistable mechanism. The actuating unit is linearly movable between a first end position in which the switching apparatus is in a closed state and a second end position in which the switching apparatus is in an open state. The linear movement defines an axis. The bistable mechanism is arranged to ensure that the actuating unit is held in either of the end positions. The bistable mechanism includes a cam means mechanically connected to the actuating unit and at least one cam follower. The invention also relates to a use of the invented apparatus.
    Type: Grant
    Filed: August 23, 2013
    Date of Patent: September 2, 2014
    Assignee: ABB Technology AG
    Inventors: Tomas Borg, Daniel Johansson
  • Patent number: 8519987
    Abstract: An operating and display device is provided for a vehicle having a display unit and having a rotary knob for selecting a function and/or for selecting a menu within a hierarchical menu structure shown using the display unit. The rotary knob forming an operating unit is movable in both directions of its rotational axis, and pressing of the operating unit causing navigation between two menu levels in a first hierarchy direction and pulling of the operating unit causing navigation between two menu levels in a second, opposing hierarchy direction of the menu.
    Type: Grant
    Filed: July 28, 2010
    Date of Patent: August 27, 2013
    Assignee: GM Global Technology Operations LLC
    Inventor: Uwe Bonne
  • Patent number: 8207466
    Abstract: The present invention relates generally to pushbutton actuators. More particularly, the invention encompasses a pushbutton 2 position twist release switch with integral LED and actuator. The invention also includes a pushbutton 3 position momentary switch with an integral LED and actuator. Another embodiment of the invention relates to a pushbutton 3 position maintained switch with an integral LED and actuator. The invention also includes various embodiments of the inventive pushbutton actuator of this invention. The inventive pushbutton also comprises a pushbutton knob that has ridges for the transmission and scattering of light for the LED in the module.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: June 26, 2012
    Assignee: Siemens Industry, Inc.
    Inventors: Neeraj Singh, Tinghao Wang, Li-Chih Ree, Xinhua Chen
  • Publication number: 20110011716
    Abstract: The present invention relates to devices that may be used in conjunction with one or more battery modules and related methods. More particularly, the present invention relates to a devices and related methods allowing one to manually disconnect high voltage and high current devices from a system. In one aspect, the present invention provides a mid pack break. The mid pack break is able to manually disconnect high voltage and high current devices from a system. The mid pack break includes a handle, a pin, a first sleeve, and a second sleeve. Force exerted on the handle causes the pin to insert into the first and second sleeves, thereby completing an electrical connection between the first and second sleeves.
    Type: Application
    Filed: May 27, 2010
    Publication date: January 20, 2011
    Inventors: Daniel J. Elliott, W. Jeff Ulrich, Rick Reinhard, David Weinberger, David Edgar
  • Patent number: 7759589
    Abstract: The present invention relates to a power window switch apparatus (1) having a switch housing (5) supporting at least one actuation element (2) for user access at a first surface (4) of the switch housing (5). The actuation element (2) is arranged to be slideable from a zero position in directions perpendicular to the first surface (4). The actuation element (2) being operable upon user manipulation to slide in a first direction outwards of the housing (5) for closing of an associated first switch element (8) for energizing an associated motor for lift of an associated window. The actuation element (2) being operable upon user manipulation to slide in a second direction, opposite to the first direction, for closing of an associated second switch element (9) for energizing the associated motor for lowering the associated window.
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: July 20, 2010
    Assignee: Ford Global Technologies, LLC
    Inventor: Jonas Wilhelm Göthlin
  • Patent number: 7488914
    Abstract: A switch is disclosed having a switch housing defining a housing interior and an access opening that extends through a wall of the housing to the housing exterior. An actuator assembly including a shaft constrained by said housing moves along a path from a normal position to an actuated position as well as a momentary position. The shaft has an actuating portion which extends outwardly from the housing interior through the access opening. A shaft body inside the housing including a generally planar contact support that supports a number of switch contacts. A housing base positions a number of terminals having conductive surfaces for biased engagement with selected switch contacts to form an electrical path between terminals when the actuator assembly is in one of either the normal, actuated or momentary positions.
    Type: Grant
    Filed: April 4, 2007
    Date of Patent: February 10, 2009
    Assignee: Delta Systems, Inc.
    Inventors: Christopher A. Kahnert, Muni Polavaram
  • Patent number: 7302758
    Abstract: There is disclosed a method for manufacturing and mounting electric contacts for control members of small dimensions, particularly for control members used in the horological field.
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: December 4, 2007
    Assignee: ETA SA Manufacture Horlogere Suisse
    Inventors: Laurent Kaelin, Yannick Hunziker, Baptist Wyssbrod
  • Patent number: 6998557
    Abstract: A power driven machine such as a food product slicer, band saw apparatus or food mixer, includes a multi-action switch assembly with first and second switch units and a switch actuator for selectively actuating the first and second switch units in a manner to trigger certain control functions of the machine.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: February 14, 2006
    Assignee: Premark FEG L.L.C.
    Inventor: Douglas J. McGuffin-Noll
  • Patent number: 6900405
    Abstract: A circuit breaker has a threaded collar fixed on a breaker housing and an approximately cylindrical actuating element displaceably guided in a bore of the threaded collar and partially protruding from the breaker housing for manual push-pull actuation in an advantageous way on the actuating side. In order to seal the circuit breaker, a sealing ring seals an annular gap formed between the wall of the bore and the circumference of the actuating element.
    Type: Grant
    Filed: November 5, 2003
    Date of Patent: May 31, 2005
    Assignee: Ellenberger & Poensgen GmbH
    Inventors: Gerd Abraham, Ewald Schneider
  • Patent number: 6737598
    Abstract: An electrical switch is provided that includes a housing having at least one contact retention chamber formed therein. The housing includes an opening in one wall of the contact retention chamber through which an actuator is extended. A contact assembly is movably mounted within the contact retention chamber of the housing. The contact assembly has at least one contact that is movable along an arcuate path aligned at an angle to the longitudinal axis of the housing. The actuator includes an insulated over-molded portion that retains a conductive member therein. The conductive member is configured to engage the contact. The housing slidably retains the actuator to permit movement of the actuator and the conductive member along the longitudinal axis of the housing. The actuator drives the contacts along the arcuate path between engaged and disengaged positions with the conductive member as the actuator moves along the longitudinal axis of the housing.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: May 18, 2004
    Assignee: Tyco Electronics Canada, Ltd.
    Inventors: David G. Allen, Mehmet U. Sayman, Liviu N. Dan
  • Publication number: 20040065534
    Abstract: A wallbox dimmer switch includes an actuator mounting frame having a platform portion that is receivable in a rectangular wallplate opening having standard toggle-type dimensions. The dimmer switch includes a pushbutton actuator for a switch and an adjacently located dimmer actuator that extend substantially parallel to a first side of the platform portion. The pushbutton actuator includes a user-engageable portion having an outer surface of which at least the end portions are defined by a portion of a substantially prolate spheroid for minimization of undesirable coupling between the adjacent actuators during actuation by a user. The switch may also include an actuator for an airgap switch extending through the platform portion and an array of indicator lights that are displayed through openings extending to an actuator-presentation surface of the platform portion.
    Type: Application
    Filed: July 16, 2003
    Publication date: April 8, 2004
    Inventors: Noel Mayo, Carl W. Gomes, Elliot G. Jacoby, Roland L. Ledyard, Michael W. Pessina, Michael A. Ryan, Joel S. Spira
  • Publication number: 20030234170
    Abstract: A manually operable, electrical operating member having two key buttons for the respective switching-on and switching-off of the current, which key buttons are arranged on mutually opposite sides and can be operated in several steps. A common, mechanically operable switch is provided with which the key buttons are each in an operative connection.
    Type: Application
    Filed: June 5, 2003
    Publication date: December 25, 2003
    Applicant: Bernstein AG
    Inventors: Rolf Wecke, Jurgen Weiss, Michael Leuschner
  • Publication number: 20030062252
    Abstract: A switch box (named a security switch) comprises a housing with a manually and/or automatically activated ON/OFF switch for a phone and/or data line connected through the switch box. A user can disconnect his computer from the Internet to eliminate hacking when the computer is not in use. A simple push/pull lever moves any available type of male/female plug from a connect to a disconnect mode. A multi-wire version is shown. A future advanced electronic filter is shown which automatically replaces confidential data like a social security number with a set of dummy data while browsing on the Internet.
    Type: Application
    Filed: July 24, 2001
    Publication date: April 3, 2003
    Inventor: Danilo E. Fonseca
  • Patent number: 6483062
    Abstract: A push-pull switch includes an actuating mechanism whose actuating tappet is engaged in a thread in the handle. By this arrangement, a pulling movement on the handle is converted into a rotational movement of the actuating tappet. As such, balls mounted as latching elements in the actuating tappet can be released gently from a secure latching position in the ON state.
    Type: Grant
    Filed: July 26, 2001
    Date of Patent: November 19, 2002
    Assignee: Siemens Aktiengesellschaft
    Inventors: Reinhard Herdegen, Peter Weiss, Rudolf Zimmermann
  • Patent number: 6444932
    Abstract: Operating means for the operating of a switch (2) in an electric current circuit, comprising an inner cylinder (6) connected to the switch, with a push rod (7) axially displaceable in the inner cylinder between an outer resting position and an inner operative position wherein the push rod acts on the switch to break the current circuit, and wherein a the push rod during displacement to the active position passes and is releasably locked in the active position by being arrested behind a spring member supported on the inner cylinder. The movement of the push rod in a direction towards the resting position is axially limited by an outer cylinder which is journalled about the inner cylinder and the cylinders are inter-locked in the coupled position through the aid of snap-lock means acting between and being encased between the cylinders in their interconnected position.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: September 3, 2002
    Assignee: ABB AB
    Inventor: Monia Resmalm
  • Patent number: 6268577
    Abstract: A push-pull switch operator includes a housing. A rotary drive is rotationally mounted in the housing and has a circumferential cam track. An actuator is operatively coupled to the rotary drive for converting linear movement of the actuator to rotary movement of the rotary drive. A pusher is received in the housing and has a follower pin riding in the cam track to convert rotary movement of the cylinder to linear movement of the pusher. The pusher actuates an electrical switch. A cap is operatively coupled to the actuator for manually operating the actuator between in, middle and out positions to selectively operate the pusher.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: July 31, 2001
    Assignee: Siemens Energy & Automation, Inc.
    Inventors: Terry L. Marquardt, Rudolf E. Zimmermann
  • Patent number: 5939989
    Abstract: An electronic switch includes a rigid base, a circuit board supported by the base which includes an aperture therethrough defined, at least in part, by spaced apart conductive terminals of an electrically conductive circuit, a resiliently flexible casing attached to the base and overlying the circuit board, and a plunger attached to the casing and extending therefrom through the circuit board aperture. The plunger includes a conductive portion which is adjacent to the casing, and a non-conductive portion. The casing is resiliently biased so as to normally position the plunger such that the non-conductive portion thereof extends through the circuit board aperture. Depression of the casing, however, places the conductive portion within the aperture and into contact with the spaced apart conductive terminals to close the electrically conductive circuit. The electronic switch may be utilized in connection with, for example, a drowsiness warning device which includes a band securable about a wearer's neck.
    Type: Grant
    Filed: May 12, 1998
    Date of Patent: August 17, 1999
    Assignee: Richard M. Bang
    Inventor: Harry H. J. Bang
  • Patent number: 5911316
    Abstract: A device for manually turning-on at least one circuit-breaker from the front panel of a cabinet includes at least one sleeve having a front end and a rear end. The sleeve extends through an aperture in the front panel and is movable between a backward position, in which the front end of the sleeve projects slightly from the front panel, and a forward position, in which the front end of the sleeve projects away from the front panel. A spring is compressed to push the sleeve from the forward position to the backward position. A rod is operably connected to the sleeve so as to be displaced following the forward movement of the sleeve and to remain in its position uneffected by the backward movement of the sleeve.
    Type: Grant
    Filed: August 17, 1998
    Date of Patent: June 15, 1999
    Assignee: Acbel Polytech, Inc.
    Inventor: Chien-Ming Chu
  • Patent number: 5725088
    Abstract: A stationary terminal 12 and a common terminal 13 are provided on a bottom of an insulating case 11. A pivot 14a is provided on an upper end of common terminal 13. A change-over plate 14 is rotatable about and brought into contact with the pivot 14a. A projection 16a, provided under slider 16, is brought into contact with and slidable along a sliding surface 14g of change-over plate 14 at a position lower than the pivot 14a. Change-over plate 14 causes a seesaw movement about the pivot 14a, and quickly accomplishes the switching movement regardless of the shifting speed of slider 16. Thus, it becomes possible to provide a switch which is highly reliable and free from burnout and welding of the contacts.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: March 10, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Mitsuo Aimi
  • Patent number: 5667060
    Abstract: A diaphragm for the contact insulating housing of a mechanically operated high voltage switch. The diaphragm has a central portion through which the shaft from the mechanical operating mechanism to the movable contact passes. The walls of the diaphragm about the central portion are mechanically joined or chemically bonded to the shaft. The diaphragm is made of such materials, is dimensioned and configured so that the diaphragm moves with the shaft and prevents relative motion therebetween. The outer rim of the diaphragm is mechanically joined or chemically bonded to the switch housing. The quality of the diaphragm and the seals permits them to withstand the application of the full operating voltage of the switch.
    Type: Grant
    Filed: December 26, 1995
    Date of Patent: September 16, 1997
    Assignee: Amerace Corporation
    Inventor: Glenn J. Luzzi
  • Patent number: 5605225
    Abstract: In a push-pull type latching control button, in particular a button for operating an electrical component, a main plunger of the control button is associated with an auxiliary plunger through which a shank of a control member can actuate the main plunger. Like the main plunger, the auxiliary plunger is releasably retained by a latching arrangement. An elastic spreader arrangement is provided between the main plunger and the auxiliary plunger. The elastic spreader arrangement also constitutes a return spring arrangement associated with the control member.
    Type: Grant
    Filed: November 15, 1995
    Date of Patent: February 25, 1997
    Assignee: Baco Constructions Electriques Anct.Baumgarten
    Inventor: Maurice Schaeffer
  • Patent number: 5586646
    Abstract: Actuator for an electrically operated vehicle door lock has an actuator plunger which is shiftable between first and second positions to lock and unlock the related door latch. The actuator plunger carries a resilient electrical contact element which coacts with one or more fixed contacts on a guide to close one or more respective circuits for operating other parts of the related system and/or signalling the condition of the related lock, such as whether it is locked or unlocked. Preferably the contacts slide into and out of engagement to provide silent operation and self-cleaning wiping action.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: December 24, 1996
    Inventors: Mark Bridgeman, Pierre Periou
  • Patent number: 5576525
    Abstract: A push button is provided with a steel ball pressed by a spring. A separate retaining spring retains the steel ball in a gap between coils of the retaining spring. The push button thus is retained at prescribed pressed down positions.
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: November 19, 1996
    Assignee: Shinkoh Electric Co., Ltd.
    Inventor: Heihachiro Umemura
  • Patent number: 5408061
    Abstract: In the subject emergency stop switch the closing ring penetrates through a face plate, surrounds a pushbutton, and on its rear side is in communication with a control element that is provided for the guidance of a cam, preloaded via a first spring. A first plunger element, in connection with the pushbutton, includes elements for the reception of the cam and the first spring and an adaptor, superimposed on a contact block, surrounds the control element, with the first plunger element actuating, upon a force input via the pushing of the pushbutton, a contact carrier, guided by a contact block, against the resilient force provided by springs. In this manner the contact sets are opened and arched contact arms are utilized which are accessible via connecting terminals with the contact arms being pretensioned in such a manner that they close the contact upon the pushing of the pushbutton.
    Type: Grant
    Filed: November 30, 1993
    Date of Patent: April 18, 1995
    Assignee: Inventio AG
    Inventor: Adolf H. Martin
  • Patent number: 5389756
    Abstract: A pushrod switch having a plastic switch housing, a pushrod with a plurality of peripheral teeth arranged in the switch housing, a movable sliding member contained within the switch housing and provided with opposing teeth engagable with the pushrod peripheral teeth and a locking catch device for releasably fixing the pushrod relative to the sliding member. The locking catch device includes two guide elements located in the sliding member and each shaped like a quarter shell; each have interior curved surfaces facing each other provided with the opposing teeth. The guide elements extend in longitudinal directions parallel to each other, are located on opposite sides of a longitudinal central plane extending vertically through both the sliding member and the pushrod, are located on opposite sides of a horizontal transverse central plane passing through the pushrod and rotated about 90.degree.
    Type: Grant
    Filed: May 5, 1993
    Date of Patent: February 14, 1995
    Assignee: Merit-Elektrik GmbH
    Inventor: Pierre Micallef
  • Patent number: 5345050
    Abstract: A switch actuating assembly supports and actuates a limit switch of the ball and roller type. The assembly includes a housing, a plunger movably positioned within the housing, and an end cap which closes off one end of the housing. The assembly is adapted to be mounted to a vehicle control panel utilizing conventional mounting hardware. Various ball and roller type limit switches are interchangeable with the housing body. The plunger is movable between a first detent position with the limit switch activated and a second spring loaded position with the limit switch deactivated.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: September 6, 1994
    Assignee: Caterpillar Inc.
    Inventors: Matthew G. Branch, Chris E. Willey
  • Patent number: 5306884
    Abstract: The present invention is a knob which attaches to the switch post of a push/pull switch. The knob selectively disengages from the switch post as the knob is inadvertently impacted, thereby isolating the push/pull switch from the impacting force. The knob moves independently of the switch post and contacts the housing supporting the switch. Consequently, the force of impact is directed to the housing through the body of the knob and very little force is directed to the switch.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: April 26, 1994
    Assignee: ITT Corporation
    Inventors: Joseph N. Caserta, Gary M. Vance
  • Patent number: 5228560
    Abstract: An electrical contact device has a first connector (1) having a surrounded base portion (3). Radially disposed within the base portion is a plurality of contact members (5) with at least a surface portion of the contact members being in electrical contact with the base portion through, at least in part, flexible, electrical conducting connections (6). Each contact member is in the form of a double-armed lever with a first arm (15) and a second arm (16) carrying the surface portion, and each contact member is pivotable about an intermediate portion (19) between the first arm and the second arm. A second connector (2) has an electrical conductive contact surface (26) and is receivable and movable in the first connector. The second connector is pressable against the first arm, such as to pivot the double-armed lever from an open position where the surface portion does not contact the conductive contact surface to a closed position where the surface portion does contact the conductive contact surface.
    Type: Grant
    Filed: December 16, 1991
    Date of Patent: July 20, 1993
    Inventor: Leif Naslund
  • Patent number: 5005923
    Abstract: A limit switch assembly for mounting on mobile storage units has first and second limit switches secured in spaced relationship. A switch operating rod is spring biased to extend from the assembly by a predetermined amount into an open aisle or where there is no proximate storage unit and there is a cam element on the rod which holds the first switch in closed circuit condition to enable a motor on the unit and drive it into the open aisle space and when the rod touches a stop as the unit means reaches the limit of its travel the cam shifts to open the first switch to initiate a deceleration interval which terminates when the cam retracts enough to open the second switch which disables the motor.
    Type: Grant
    Filed: March 9, 1990
    Date of Patent: April 9, 1991
    Assignee: Spacesaver Corporation
    Inventor: Dean L. Dahnert
  • Patent number: 4939329
    Abstract: A roller activated switch with an unlimited number of triggering points, a preferred embodiment featuring linear activation by a rod upon the roller. The switch unit receives a moveable member upon the roller in its housing. The moveable member rolls a spring-biased roller to an off center position, thus activating or deactivating contacts upon any movement of the moveable member beyond a small increment. The switch rapidly responds to any reversing movement of the moveable member upon the roller no matter what absolute position the moveable member is in, at the time, thus having an unlimited number of changeable triggering points independent of contact pressure and having an overtravel limited only by the length of the moveable member. This feature results in the switch having the ability to establish its own triggering points. Thus, absolute triggering becomes automatic.
    Type: Grant
    Filed: May 22, 1989
    Date of Patent: July 3, 1990
    Inventor: Norman H. Dankert
  • Patent number: 4922225
    Abstract: An improved system for lighting an automobile central rear window warning, or "third" red light, employs an unlimited linear motion switch coupled to the accelerator-carburetor linkage and a logic unit coupled to the switch and the electric lines for the conventional brake, turn signal and back-up signal maps, and, optionally, to a clutch switch, so as to light the "third" warning lamp. The linear switch unit receives a rod in its housing, which rod is coupled to the carburetor or accelerator linkage. The rod rolls a spring-mounted roller to an off center position, thus activating or deactivating a pair of contacts upon any movement of the rod beyond a small increment. The linear switch rapidly responds to any reversing movement of the accelerator pedal, no matter what absolute position the rod is in at the time.
    Type: Grant
    Filed: March 20, 1987
    Date of Patent: May 1, 1990
    Inventor: Norman H. Dankert
  • Patent number: 4902865
    Abstract: The invention relates to a push-pull actuator for key switches with a mushroom knob (1) which is loaded by a restoring force and is supported longitudinally movable. This mushroom knob (1) is separated from the actuating plunger. This actuating plunger is spring-loaded in the switching direction and is locked in the operating position by rocker levers (13). The locking is cancelled by a relative motion between the mushroom knob (1) and the actuating plunger (6) by the sliding of inclined surfaces (23) at the edges of the rocker levers (13) so that the actuating plunger is moved into the off position by the spring (20). In the off position, the rocker levers (13) with the back sides (19) are brought into engagement with the end faces (18) of the rocker levers.
    Type: Grant
    Filed: November 16, 1988
    Date of Patent: February 20, 1990
    Assignee: Siemens Aktiengesellschaft
    Inventors: Herbert Muller, Gerhardt Sehnke