Patents by Inventor Derald H. Kraft

Derald H. Kraft has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4551122
    Abstract: A sheet steel poly-V-grooved pulley having a special cross-sectional contour is made optionally by any one of three different cold working manufacturing procedures. Special physical properties or characteristics are developed in the pulley by the manner in which the metal in the V-groove body and single and double walled terminal flanges are cold worked. The cold working involves forming in stages of manufacturing from a cup-shaped blank to the finished pulley product a stepped inner body wall surface equivalent to a tapered surface with improved substantially uniform torque transmitting strength in the grooved body from web wall to open end. Also involved in the cold working is an increase in pulley diameter in certain portions of the finished pulley and a decrease in diameter in other portions from the diameter of the side wall of the cup shaped starting blank.
    Type: Grant
    Filed: February 22, 1983
    Date of Patent: November 5, 1985
    Assignee: Dyneer Corporation
    Inventors: Derald H. Kraft, Gary L. Hitchcock
  • Patent number: 4355991
    Abstract: A hydraulic tensioning arrangement for an endless drive belt for a vehicle accessories drive system. The vehicle alternator is pivotally mounted on the engine and is driven by a pulley which is drivingly engaged with the drive belt. A hydraulically actuated piston is mounted in a generally fixed position on the engine closely adjacent to the alternator and is operatively connected to the alternator for pivotally moving it to a belt tensioning position. Hydraulic fluid is supplied to the piston cylinder from the vehicle's power steering fluid supply. A ratchet bar is mounted on the piston cylinder and is slidably engaged in a guide bracket mounted on the alternator. A spring-biased pawl is mounted on the guide bracket and is engageable with a series of teeth formed on the extended end of the ratchet bar.
    Type: Grant
    Filed: August 3, 1979
    Date of Patent: October 26, 1982
    Assignee: Dyneer Corporation
    Inventor: Derald H. Kraft
  • Patent number: 4321819
    Abstract: A gap-framed type press has a horizontal bed which holds a lower die that cooperates with an upper die mounted on a vertically reciprocally movable ram to perform a metal-working operation therebetween. Hydraulic cylinders are operatively engaged with the ram for moving the die members into and out of engagement. The ram is movably mounted on a pair of spaced vertical side plates which are bolted to the press bed. The bed is supported on a pair of side frame members by a pair of spaced spherical bearings. The side frame members extend parallel with and closely adjacent to the ram-carrying side plates and are connected to the side plates by a sliding connection. The elastic bending and deformation forces which are applied to the press frame during each operation are transmitted between the side frame members and side plates through their sliding connection and between the bed and side frame members by the spherical bearings.
    Type: Grant
    Filed: July 23, 1980
    Date of Patent: March 30, 1982
    Assignee: Dyneer Corporation
    Inventors: Derald H. Kraft, William S. Wagner
  • Patent number: 4299583
    Abstract: A hydraulic tensioning device for maintaining a predetermined amount of tensioning force on an endless drive belt of a vehicle accessories drive system. A housing is mounted in a fixed position on the engine in close proximity to the drive belt. A shaft is movably mounted within the housing by an elastomer block which biases the shaft in a belt tensioning rotational direction. A lever extends outwardly from the housing and is integrally connected to the shaft for pivotal movement upon rotation of the shaft. An expandable bladder or actuator is mounted in the housing and is engageable with the shaft and pivots the rotor and lever toward a belt tensioning direction when the bladder is expanded by hydraulic fluid. A hydraulic fluid supply and pump assembly supplies fluid under pressure to inflate the bladder. An idler pulley drivingly engages the fluid pump and is driven by the endless drive belt for actuating the pump.
    Type: Grant
    Filed: October 31, 1979
    Date of Patent: November 10, 1981
    Assignee: Dyneer Corporation
    Inventors: Derald H. Kraft, Daniel M. Rinaldo
  • Patent number: 4289007
    Abstract: Apparatus for forming a sheet metal pulley from a cup-shaped blank in a single hydraulic forming operation. A pair of die holding members supports a plurality of groove-forming inner dies and is movably mounted on a base for horizontal reciprocal movement between open and closed die positions for capturing a pulley-forming blank therebetween. Tapered pins extend vertically through aligned openings formed in overlapping shelf members of the die holding members to wedgingly clamp the dies toward each other and to lock them in a horizontally closed position. A ram plate is mounted on a plurality of vertical posts for reciprocal vertical movement with respect to the captured blank. The ram plate has a top die which exerts axial pressure on the hub portion of the blank during the hydraulic bulging of the blank side wall by a confined fluid within the blank in cooperation with the groove-forming inner dies.
    Type: Grant
    Filed: December 5, 1979
    Date of Patent: September 15, 1981
    Assignee: Dyneer Corporation
    Inventor: Derald H. Kraft
  • Patent number: 4285676
    Abstract: A tensioning device for maintaining a predetermined amount of tensioning force on an endless drive belt for a vehicle accessories drive system. A housing is mounted in a fixed position on the vehicle engine adjacent the drive belt. A lever is pivotally mounted on a shaft which is located within the housing and extends generally radially outwardly from the housing and is adapted to move in a belt tensioning direction. A first pair of cylindrical, torsional coil springs is telescopically mounted on the shaft, with the springs being located one on each side of the lever. A second pair of cylindrical, torsional coil springs is telescopically concentrically mounted on the shaft and surrounds the first spring pair. One end of each spring is attached to the housing with the other spring ends being attached to the lever. The spring pairs are placed in torsion and bias the lever in the belt tensioning direction.
    Type: Grant
    Filed: December 17, 1979
    Date of Patent: August 25, 1981
    Assignee: Dyneer Corporation
    Inventor: Derald H. Kraft
  • Patent number: 4283182
    Abstract: A hydraulic tensioning device and arrangement which maintains a predetermined amount of tensioning force on an endless drive belt of the vehicle accessories drive system. A hydraulically actuated piston applies a predetermined force to one of the vehicle accessories which is pivotally mounted with respect to the engine to tension the drive belt which is drivingly connected to this vehicle accessory. A self-contained hydraulic fluid supply and pump assembly is mounted in a fixed position on the vehicle engine and has a fluid pressure line connected to the piston for hydraulic actuation of the piston. An idler pulley is rotatably mounted on the fluid supply and pump assembly and is engaged with and driven by the drive belt for actuating the pump to supply hydraulic fluid from the fluid supply to the piston. A coil spring mounted within the piston cylinder applies a portion of the tensioning force on the belt tensioning accessory with the major portion of the tensioning force being applied hydraulically.
    Type: Grant
    Filed: August 3, 1979
    Date of Patent: August 11, 1981
    Assignee: Dyneer Corporation
    Inventor: Derald H. Kraft
  • Patent number: 4277240
    Abstract: A hydraulic tensioning device for maintaining a predetermined amount of tensioning force on an endless drive belt for the vehicle accessories drive system. A self-contained hydraulic fluid supply and pump assembly is mounted on the swinging end of a pivotally mounted lever and is moved toward the drive belt by a hydraulically actuated piston which is mounted in a fixed position on the engine. An idler pulley is rotatably mounted on the fluid supply and pump assembly and is engaged with and driven by the drive belt. The drive belt rotates the idler pulley which hydraulically actuates the piston by driving the pump which supplies hydraulic fluid to the piston from the fluid supply. The piston pivots the lever toward the belt whereupon the idler pulley engages the belt and exerts the desired tensioning force on the belt. Check valves in the pump assembly regulate the amount of hydraulic force applied to the piston and ultimately to the belt.
    Type: Grant
    Filed: August 6, 1979
    Date of Patent: July 7, 1981
    Assignee: Dyneer Corporation
    Inventor: Derald H. Kraft
  • Patent number: 4276038
    Abstract: A hydraulic tensioning device for maintaining a predetermined amount of tensioning force on an endless drive belt for the vehicle accessories drive system. A hydraulic cylinder is adapted to be mounted in a fixed position with respect to the vehicle engine and is operatively connected to the low-pressure hydraulic fluid system of the engine. A bellcrank mechanism is pivotally mounted on the cylinder and has a belt-engaging idler pulley rotatably mounted on an extended end of one of the levers. The other lever is operatively engaged by the cylinder piston which moves the idler pulley into tensioning engagement with the drive belt. The cylinder has a plurality of discs mounted in a spaced relationship on the piston rod for imparting movement to the rod when acted upon by hydraulic fluid. Each disc forms a movable forward wall of a separate hydraulic subchamber located within the cylinder. A hollow bore is formed in the rear portion of the piston rod to provide a fluid passage between the spaced subchambers.
    Type: Grant
    Filed: July 26, 1979
    Date of Patent: June 30, 1981
    Assignee: Dyneer Corporation
    Inventor: Derald H. Kraft
  • Patent number: 4270906
    Abstract: A belt tensioner for an endless drive belt for vehicle accessories has a shaft which is mounted in a fixed position adjacent the belt. A lever is pivotally mounted on the shaft and has an idler pulley rotatably mounted on an extended end of the lever. The pulley is movable into tensioning engagement with the belt by rotation of the lever. A first cam plate is slidably mounted on the shaft and is engaged with a second cam plate which is attached to the lever for rotation with the lever. The cam plates each have a plurality of a series of camming surfaces which are mutually engageable with the opposite cam plate surfaces. A plurality of spring discs are telescopically mounted on the shaft and bias the first camming block into engagement with the second block applying a rotational force on the lever to move the pulley into tensioning engagement with the drive belt.
    Type: Grant
    Filed: November 5, 1979
    Date of Patent: June 2, 1981
    Assignee: Dyneer Corporation
    Inventors: Derald H. Kraft, Daniel M. Rinaldo
  • Patent number: 4109542
    Abstract: A method of making a dynamically balanced V-grooved sheet metal pulley from a flat sheet metal disc by roller spinning and splitting tools. The disc is provided with a central hole for mounting the disc on rotating die means between first headstock and tailstock die form assemblies of a spinning machine. The spinning tool presses the disc against an end of a headstock die form and moves generally radially outwardly pressing a portion of the die against the end of the die to provide a circular hub wall. The spinning tool then moves in a series of passes along the headstock die form thereby rolling, forming and ironing the rotating outer metal portions of the disc against the die and forming an axially extending cylindrical side wall terminating in a radially outwardly extending annular flange of a cup-shaped stage blank. The flange then is trimmed to a predetermined length and to form a peripheral axially extending edge on the flange.
    Type: Grant
    Filed: October 14, 1976
    Date of Patent: August 29, 1978
    Assignee: Aspro, Inc.
    Inventor: Derald H. Kraft
  • Patent number: 4090284
    Abstract: A sintered pulley hub construction for mounting on a bottom wall of a sheet metal pulley cup. A pair of tubular members is pressure formed in a green compact state from a metal powder mixture. One of the members has a cylindrical body which terminates at one end in an outwardly extending annular flange which forms a hub pulling flange. The other member has an interior annular cavity formed in one end and a radially outwardly extending annular flange formed on the other end. The cylindrical body of the one member is telescopically received within the annular cavity of the other member. The members are joined by sintering to form an integral homogeneous body. The outer surface of the other member has a cylindrical portion extending axially between the radial end flange and an annular shoulder for receiving an axially extending flange of a pulley cup, with the shoulder providing a zone for welding the pulley cup to the hub.
    Type: Grant
    Filed: April 5, 1977
    Date of Patent: May 23, 1978
    Assignee: Aspro, Inc.
    Inventor: Derald H. Kraft
  • Patent number: 4056014
    Abstract: A sintered pulley hub construction for mounting on a bottom wall of a sheet metal pulley cup. A pair of tubular members is pressure formed in a green compact state from a metal powder mixture. One of the members has a cylindrical body which terminates at one end in an outwardly extending annular flange which forms a hub pulling flange. The other member has an interior annular cavity formed in one end and a radially outwardly extending annular flange formed on the other end. The cylindrical body of the one member is telescopically received within the annular cavity of the other member. The members are joined by sintering to form an integral homogeneous body. The outer surface of the other member has a cylindrical portion extending axially between the radial end flange and an annular shoulder for receiving an axially extending flange of a pulley cup, with the shoulder providing a zone for welding the pulley cup to the hub.
    Type: Grant
    Filed: April 26, 1976
    Date of Patent: November 1, 1977
    Assignee: Aspro, Inc.
    Inventor: Derald H. Kraft
  • Patent number: 4056291
    Abstract: A method of making a dynamically balanced integral clutch housing and bearing assembly from a flat sheet metal disc by a roller spinning tool. A bearing and the metal disc is mounted on rotating die means between headstock and tailstock die form assemblies of a spinning machine. The spinning tool presses the disc against an end of the bearing to provide a bottom web wall of a cup-shaped bearing housing. The spinning tool then moves in a series of passes along the bearing outer race and along the headstock die form thereby rolling, forming and ironing rotating outer metal portions of the disc against the bearing and die, and forming an annular circumferential flange wall of the bearing housing which terminates in an annular shoulder. The bearing is telescopically mounted and retained within the bearing housing by the side and web walls and retaining shoulder.
    Type: Grant
    Filed: October 26, 1976
    Date of Patent: November 1, 1977
    Assignee: Aspro, Inc.
    Inventors: Derald H. Kraft, Richard C. St. John
  • Patent number: 4055976
    Abstract: A method of making a dynamically balanced cup-shaped blank for use in the production of a V-grooved pulley from a flat sheet metal disc by flow forming the metal with an improved metal spinning roller construction. The disc is mounted on rotating die means between headstock and tailstock die forming assemblies of a spinning machine. A first spinning roller pressure shear forms and thins an intermediate annular portion of the disc along a conical surface of the headstock die to form a conical wall of the cup-shaped blank, with an unworked outer annular portion of the disc extending outwardly of the conical wall. A plurality of the improved rollers are moved axially along and parallel with the headstock die means in a single pass. Outer curved front end surfaces of the rollers lay the outer unworked annular portion of the disc along a cylindrical surface of the headstock die form without materially reducing the metal thickness to rough form a cylindrical wall of the cup-shaped blank.
    Type: Grant
    Filed: March 29, 1976
    Date of Patent: November 1, 1977
    Assignee: Aspro, Inc.
    Inventor: Derald H. Kraft
  • Patent number: 4050321
    Abstract: A one-piece, sheet metal multi V-grooved pulley has a circular hub wall integrally connected with a cylindrical side wall, which side wall terminates in an open end opposite of the hub wall. A series of outwardly opening V-shaped grooves is formed by pairs of V-shaped flange walls in the cylindrical side wall. The pairs of flange walls decrease in metal thickness progressively from the hub wall toward the open end.The V-grooved pulley is made by forming a cup-shaped stage blank having a bottom hub flange wall and a connected outer cylindrical wall terminating in an open end. The stage blank is formed by roller spinning an outer annular portion of a sheet metal disc along a stepped cylindrical surface of a headstock die. A series of integrally connected cylindrical surfaces is formed along the interior of the cylindrical wall of the stage blank by the roller spinning operation.
    Type: Grant
    Filed: March 15, 1976
    Date of Patent: September 27, 1977
    Assignee: Aspro, Inc.
    Inventor: Derald H. Kraft
  • Patent number: 4041746
    Abstract: A method of making a dynamically balanced V-grooved sheet metal pulley from a flat sheet metal disc by roller spinning and splitting tools. The disc is provided with a central hole for mounting the disc on rotating die means between first headstock and tailstock die form assemblies of a spinning machine. The spinning tool presses the disc against an end of a headstock die form and moves generally radially outwardly pressing a portion of the die against the end of the die to provide a circular hub wall. The spinning tool then moves in a series of passes along the headstock die form thereby rolling, forming and ironing the rotating outer metal portions of the disc against the die and forming an axially extending cylindrical side wall terminating in a radially outwardly extending annular flange of a cup-shaped stage blank. The flange then is trimmed to a predetermined length and to form a peripheral axially extending edge on the flange.
    Type: Grant
    Filed: August 16, 1976
    Date of Patent: August 16, 1977
    Assignee: Aspro, Inc.
    Inventor: Derald H. Kraft
  • Patent number: 4016642
    Abstract: A method of making a dynamically balanced integral clutch housing and bearing assembly from a flat sheet metal disc by a roller spinning tool. A bearing and the metal disc is mounted on rotating die means between headstock and tailstock die form assemblies of a spinning machine. The spinning tool presses the disc against an end of the bearing to provide a bottom web wall of a cup-shaped bearing housing. The spinning tool then moves in a series of passes along the bearing outer race and along the headstock die form thereby rolling, forming and ironing rotating outer metal portions of the disc against the bearing and die, and forming an annular circumferential flange wall of the bearing housing which terminates in an annular shoulder. The bearing is telescopically mounted and retained within the bearing housing by the side and web walls and retaining shoulder.
    Type: Grant
    Filed: August 4, 1975
    Date of Patent: April 12, 1977
    Assignee: Aspro, Inc.
    Inventors: Derald H. Kraft, Richard C. St. John
  • Patent number: 3995474
    Abstract: A method of making a dynamically balanced V-grooved sheet metal pulley from a flat sheet metal disc by roller spinning and splitting tools. The disc is provided with a central hole for mounting the disc on rotating die means between first headstock and tailstock die form assemblies of a spinning machine. The spinning tool presses the disc against an end of a headstock die form and moves generally radially outwardly pressing a portion of the die against the end of the die to provide a circular hub wall. The spinning tool then moves in a series of passes along the headstock die form thereby rolling, forming and ironing the rotating outer metal portions of the disc against the die and forming an axially extending cylindrical side wall terminating in a radially outwardly extending annular flange of a cup-shaped stage blank. The flange then is trimmed to a predetermined length and to form a peripheral axially extending edge on the flange.
    Type: Grant
    Filed: July 7, 1975
    Date of Patent: December 7, 1976
    Assignee: Aspro, Incorporated
    Inventor: Derald H. Kraft
  • Patent number: 3991598
    Abstract: A method of making a dynamically balanced cup-shaped blank for use in the production of a V-grooved pulley, from a flat sheet metal disc by a roller spinning tool. The disc is provided with a central hole for mounting the disc on rotating die means between headstock and tailstock die form assemblies of a spinning machine. The spinning tool presses the disc against an end of a headstock die form and moves generally radially outwardly pressing a portion of the disc against the end of the die form to provide a bottom wall of the desired cup-shaped blank. The spinning tool then moves in a series of passes along the headstock die form thereby rolling, forming and ironing rotating outer metal portions of the disc against the die, and forming the disc with an annular reversely angled conical flange and an axially extending cylindrical side wall which terminates in an open end.
    Type: Grant
    Filed: June 6, 1975
    Date of Patent: November 16, 1976
    Assignee: Aspro, Incorporated
    Inventor: Derald H. Kraft