Reciprocating Cam Sleeve Patents (Class 279/57)
  • Patent number: 10850319
    Abstract: A hand held flaring tool for flaring an end of a tube includes a body portion and a handle portion. The body portion receives the tube therein and includes a locking actuator operable to actuate a locking mechanism to secure the tube in the body portion. The body portion includes a flaring actuator operable to actuate a flaring mechanism to flare the end of the tube when the tube is secured in the body portion. The handle portion includes a grip portion that is grasped by a user's hand for supporting the body portion of the flaring tool during a flaring process of the tube. While the user is holding the handle portion to support the hand held flaring tool, the user is able to access and actuate first and second user inputs disposed at and accessible at the handle portion to actuate the locking actuator and flaring actuator.
    Type: Grant
    Filed: November 10, 2016
    Date of Patent: December 1, 2020
    Assignee: AGS COMPANY AUTOMOTIVE SOLUTIONS, LLC
    Inventors: Mark J. Hasenberg, Logan D. Pitts, John M. Peirce
  • Patent number: 8678262
    Abstract: A quick-clamping mechanism for an electric hammer for clamping fasteners such as nails includes a biasing assembly for making the clamping assembly movable between a closed position and an opened position. The clamping assembly includes at least two clamping claws, pivotally connected to a pivot shaft including the combination of a torsion spring and a magnet. Fasteners such as nails and the like, can be clamped or released by the two clamping claws rotating relative to the pivot shaft, so that the quick-clamping mechanism has a simple structure and is easily implemented. The two clamping claws can be automatically closed, after a nail is loaded, by providing a torsion spring or a magnet on the two clamping claws, so that the quick-clamping mechanism can be operated expediently and the nail clamped securely.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: March 25, 2014
    Assignee: Chervon (HK) Limited
    Inventors: Hongtao Zhou, Jinhua Wu, Liang Chen, Guigong Ni
  • Patent number: 8075001
    Abstract: Disclosed is a chuck comprising a base (10) in which a plurality of radially continuous, longitudinal slots (41) are provided for an individual clamping jaw (11, 21), respectively. The clamping jaws (11, 21) encompass one respective stopping surface (34) and can be displaced radially relative to the base (10) when a slanted clamping jaw surface (34) and a complementary surface (4) are moved towards each other such that a surface (14) of each clamping jaw (11, 21) clamps a workpiece that is to be retained around the longitudinal axis (20) of the base (10). Each clamping jaw (11, 21) is provided with a stop area (33 or 29) that extends on a plane running perpendicular to the longitudinal axis (20) of the base (10).
    Type: Grant
    Filed: July 5, 2005
    Date of Patent: December 13, 2011
    Assignee: Gemenda AG
    Inventor: Luigi Ghezzi
  • Patent number: 7726031
    Abstract: A knife system for providing efficient replacement of a knife blade. The knife system generally includes a body, a lever pivotally connected to the body, a collet connected to the body, and a shaft connected between the lever and the collet. When the lever is in a closed position, the shaft applies tension to the collet resulting in frictional engagement with a blade within the collet. An illuminating unit is preferably positioned within the body directing light towards the blade within the collet to illuminate a work area.
    Type: Grant
    Filed: May 8, 2007
    Date of Patent: June 1, 2010
    Inventor: Douglas P. Gibbs
  • Patent number: 6726221
    Abstract: A collet chuck assembly includes a mount, a selectively-axially-movable collet closing sleeve, and a multiple-segment collet head. The collet head includes two axially-spaced outer circumferential cam surfaces that engage two axially-spaced inner circumferential cam surfaces of the closing sleeve. A quick-release cap attached to the mount includes two inwardly-radially-extending tabs that engage two outwardly-radially-extending lips of the collet head to prevent the collet head from moving axially relative to the cap. Flat resilient collet seals are disposed between each set of adjoining collet segments to prevent debris from getting into the collet chuck assembly between the segments. The collet seals maintain full-surface contact with adjoining segments even when the collet head is fully opened. A slinger bore formed in the cap directs debris radially-outwardly out of the collet chuck assembly.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: April 27, 2004
    Assignee: Hardinge Inc.
    Inventors: Donald N. Terwilliger, Neal R. Des Ruisseaux, David B. Myers
  • Patent number: 6719303
    Abstract: A drill rod chuck in which the closing of the jaws is effected through the use of gas springs mounted in the slidable jaw actuating jaw bowl. Further the jaws are supported by bushings against cantilever loading during drilling and the jaws are positively advanced and retracted through slidable interengagement with the jaw bowl.
    Type: Grant
    Filed: October 26, 2001
    Date of Patent: April 13, 2004
    Assignee: Boart Longyear International Holdings, Inc.
    Inventor: John Thomas Stephens
  • Patent number: 6533292
    Abstract: A pull-to-close collet chuck for use with lathes equipped with servo-type bar loaders. The chuck is configured to be coupled to a lathe drawtube and translates linear movement of the drawtube to a work-gripping action to a collet. The chuck generally includes a ramp body surrounding a first portion of the collet and integral means for fixing the ramp body within a central bore of the chuck. A piston surrounds the collet and has a bearing surface adjacent a ramp surface of the ramp body, and a wedge is located between the ramp surface of the ramp body and the bearing surface of the piston. The wedge has multiple bearing surfaces through which the work gripping action is transferred from the piston to the collet as a result of radial inward movement of the wedge.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: March 18, 2003
    Assignee: Production Dynamics
    Inventor: James A. Fant
  • Publication number: 20020145261
    Abstract: A true length collet chuck assembly is adapted to receive and actuate a quick change, segmented collet having a flange extending radially outwardly from the outer surface of the collet adjacent a rear face of the collet. The collet chuck assembly comprises a chuck body having a longitudinally extending bore defined by an inwardly facing, cylindrical surface on the chuck body. The inwardly facing, cylindrical surface on the chuck body defines a circumferential groove for receiving the radially outwardly extending flange on the collet to thereby restrain the collet against axial movement relative to the chuck body. A collet closing sleeve, disposed within the chuck body and axially displaceable relative thereto, has an outwardly flaring interior surface adapted to engage an outwardly flaring surface on the collet.
    Type: Application
    Filed: April 6, 2001
    Publication date: October 10, 2002
    Applicant: Advanced Tool Systems, Inc.
    Inventors: James A. Humphrey, Donald W. Ferris
  • Patent number: 6264208
    Abstract: To provide a chuck assembly which is superior in practical usability and workability in clamping and fixing a tool to a spindle without fail and with ease by lever-operation of a specialized operational jig, a taper portion is provided on at least one of an inner circumferential wall of the sleeve portion and an outer circumferential wall of the tool clamping portion, the tool clamping portion and the sleeve portion are brought into contact with each other at the taper portion, a retainer portion for retaining the operational jig is provided on the sleeve portion, a support portion is provided in a predetermined position of the chuck assembly body for supporting the operational jig retained at the retainer portion, the sleeve portion retained by the operational jig is slidingly moved relative to the tool clamping portion when the operational jig is lever-operated in a taper direction of the taper portion by using the support portion as a fulcrum, and the opening portion of the tool clamping portion is widened
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: July 24, 2001
    Assignee: Ukiwa Seiko Kabushiki Kaisha
    Inventors: Kazuo Sakamaki, Akira Sakamaki, Tetuo Seki, Hisashi Ikehara
  • Patent number: 6257595
    Abstract: A collet chuck assembly includes an annular mount adapted to be attached to a spindle of a turning machine, a tubular collet sleeve disposed internally to the mount including an inner tapered cam surface and adapted to be coupled to an axial moving mechanism of the turning machine, and a tubular collet structure dispose interiorly of the collet sleeve and having a cooperating tapered, outer cam surface. An annular retaining cap has retaining lugs adapted to be engaged with locking flanges of the mount upon engagement of the cap with the mount and rotation of the cap with respect to the mount. The installed cap engages a front end of the collet structure to retain the collet structure within the collet sleeve. A cap anti-rotation mechanism includes an anti-rotation pin carried within the mount for reciprocating axial movement with respect to the mount between extended and retracted positions and a pin actuating mechanism for selectively effecting the reciprocating axial movement.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: July 10, 2001
    Assignee: Hardinge Inc.
    Inventors: Anthony J. Difasi, Donald N. Terwilliger
  • Patent number: 6059336
    Abstract: A connector unit is disclosed which comprises a shaft, a plurality of collet fingers, and a sleeve. The plurality of collet fingers are peripherally positioned against the generally cylindrical outside surface of the shaft adjacent the lower end of the shaft. The sleeve has an upper end, a lower end, and a generally cylindrical inside surface positioned peripherally around the shaft. The sleeve is provided with a radially inwardly extending annular flange extending from its inside surface between its upper end and its lower end which forms a seal with the generally cylindrical outside surface of the shaft. An upper annular chamber is formed between the generally cylindrical outside surface of the shaft and the generally cylindrical inside surface of the sleeve above the radially inwardly extending flange and a lower annular chamber is formed between the generally cylindrical outside surface of the shaft and the generally cylindrical inside surface of the sleeve below the radially inwardly extending flange.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: May 9, 2000
    Assignee: Kvaernet Oilfield Products
    Inventor: Richard A. Meronek
  • Patent number: 5921561
    Abstract: The present invention is a collet assembly with a sliding lock. The assembly includes a segmented tubular body with the segments being increasing in size from one end of the body to the other. The two smallest segments form a plug for securing the collet assembly to a first object. The two larger segments form a collet which receives a second object. The collet has a tapered cross-sectional area, with the area decreasing from the end of the collet assembly towards the middle of the collet assembly. The collet includes longitudinal slots that extend from the end towards the middle of the collet assembly. The collet may include a sleeve in its bore. Like the collet, the sleeve has a plurality of longitudinal slots. The collet assembly also includes a slidable tubular collet lock having a passageway for receiving said collet therethrough.
    Type: Grant
    Filed: February 26, 1997
    Date of Patent: July 13, 1999
    Assignee: Cedarberg Industries, Inc.
    Inventor: John F. Cedarberg, III
  • Patent number: 5855377
    Abstract: A collet chuck assembly includes a chuck body carrying a collet retaining ring for receiving the threaded rear end of a standard collet. The collet retaining ring is secured to the chuck body and held against both axial and radial movement relative to the chuck body by a plurality of radially extending fasteners having inner, tapered portions received by correspondingly tapered holes in the retaining ring. A longitudinally or axially displaceable closing sleeve compresses the collet jaws when the sleeve is moved inone axial direction and releases the jaws when moved in the other axial direction. Axial displacement of the closing sleeve is effected by a collet actuator including a plurality of longitudinal fingers extending through openings in the collet retaining ring and having end portions configured to interlock with a correspondingly configured mating portion of the collet closing sleeve.
    Type: Grant
    Filed: November 13, 1996
    Date of Patent: January 5, 1999
    Inventor: William G. Murphy
  • Patent number: 5613692
    Abstract: A circular flexible collet that provides a 360 degree gripping engagement with a cylindrical workpiece and which is operable by an actuator member incorporated in a workpiece chuck. The collet may be constructed as an internal collet for gripping engagement with a workpiece internal periphery, or as an external collet for gripping engagement with a workpiece external periphery. The flexible collet may be used for single, or plural workpiece gripping actions. The collet includes a spring steel body having a radial opening and an outer and an inner circular periphery. One circular periphery is a workpiece gripping surface, and the other circular periphery has a tapered cam surface engageable by a workpiece chuck actuator member. The tapered cam surface has a plurality of circumferentially spaced apart slots having an open outer end. In an internal collet the tapered cam surface is formed around the collet body inner periphery.
    Type: Grant
    Filed: August 25, 1995
    Date of Patent: March 25, 1997
    Inventor: Don R. Lloyd
  • Patent number: 5414888
    Abstract: An improved plumbers' tool of the type employing a helically wound coiled spring which is controllably inserted into waste lines to remove blockages. In operating the tool of the invention, a storage drum from which the clean-out spring is payed out is rotated, usually by a small electric motor, and the spring is clamped in a chucking mechanism so as to rotate with the housing. The improvement of the present tool resides in the provision of a unique actuating mechanism which provides a substantial mechanical advantage that enables the operator, using only one hand to grip a forwardly positioned stationary handle with the fingers and move a pivotally movable, rearwardly positioned handle with the heel of the hand to cause the chucking mechanism to positively engage the coiled spring in a manner to prevent slippage even under severe torque loading conditions.
    Type: Grant
    Filed: June 24, 1994
    Date of Patent: May 16, 1995
    Assignee: Augerscope, Inc.
    Inventor: Lawrence F. Irwin
  • Patent number: 5037254
    Abstract: A tool clamping device comprises an axial sleeve having a forwardly tapering internal surface. A radially compressible ring is disposed on the internal surface. An axially compressible spring opposes axial movement of the ring while permitting axial rearward movement of the sleeve whereby the tapering surface of the sleeve compresses the ring radially inwardly into coupling engagement with a groove formed in a tool holder.
    Type: Grant
    Filed: January 18, 1990
    Date of Patent: August 6, 1991
    Assignee: Sandvik AB
    Inventor: Lars-Gunnar Asberg
  • Patent number: 5029881
    Abstract: A chuck jaw assembly for use in an apparatus for setting fasteners is disclosed having an elastomeric connector, or retaining member, that holds the jaw teeth of the chuck jaw assembly in the proper axial and circumferentially spaced positions with respect to each other. The jaw teeth have a forward conical section and a rear cylindrical section with a groove formed at an outer periphery. A ring portion of the retaining member is received int he groove and spacer elements that extend inwardly from an inner periphery of the ring portion are received in circumferential gaps between the jaw teeth to ensure that they are maintained in the proper circumferentially spaced positions. A mold having the proper configuration for forming the retaining member is disclosed. An elastomeric material is injected into the mold and is allowed to cure. The retaining member is then removed from the mold.
    Type: Grant
    Filed: July 13, 1989
    Date of Patent: July 9, 1991
    Assignee: GBP Corporation
    Inventor: Bruce Godfrey
  • Patent number: 4997325
    Abstract: In a chuck for axially clamping two machine parts which are releasable from each other, on the first machine part (1) are provided a hollow centring attachment (3), a contact face (6) surrounding the attachment, and an annular groove (8) formed on the inside of the attachment (3) and comprising a groove flank (9) tapering conically towards the free end of the attachment. The second machine part (2) comprises a holding bore (4) which is adapted to the attachment (3) and which is surrounded by an end face (7) against which the contact face (6) can be pressed. In the second machine part are provided several clamping jaws (10) which are each supported by a first end (10a) against a groove flank (12) in the second machine part (2).
    Type: Grant
    Filed: April 26, 1989
    Date of Patent: March 5, 1991
    Assignee: Ott Maschinentechnik GmbH
    Inventors: Helmut Heel, Franz Friedl
  • Patent number: 4971340
    Abstract: The collect (20) is composed of a foundation body (21) and a closer (22). The foundation body (21) can be connected to the tightening device of a machine tool. The closer (22) is divided into individual clamping jaws (38) which are connected to one another permanently by means of intermediate members made of a rubber-elastic compound. The foundation body (21) and the closer (22) are coupled to one another by means of a coupling device (24) which is positive in the axial direction and nonpositive in the radial direction. The coupling device (24) includes projections (42) arranged ont he closer part (22) and protruding radially outwards and a matching number of openings (48) on the foundtion body (21).
    Type: Grant
    Filed: June 6, 1989
    Date of Patent: November 20, 1990
    Inventor: Gerhard Rall
  • Patent number: 4867463
    Abstract: A pipe holding collet is provided with an insert assembly that can be readily and quickly changed without the use of tools so as to adapt the collet to hold tubes of different sizes. The insert assembly is formed of a number of identical longitudinally separate segments, radially urged outwardly by compression springs and held together in a unitary assembly by a segment encircling retainer ring. The radially contractible and expandable assembly is releasably held within the bore of a master collet by means of an interengaging circumferential groove on the inner surfaces of the master collet fingers and circumferential ribs on the outer surfaces of the insert segments.
    Type: Grant
    Filed: September 2, 1988
    Date of Patent: September 19, 1989
    Assignee: Eaton Leonard Technologies, Inc.
    Inventor: Werner G. Hopf
  • Patent number: 4858938
    Abstract: A collet head for securing to a collet body for machine tools has a plurality of spaced segments arranged in a circular configuration having spaced slots between each segment. Each segment has a front face, a rear face, an inside work gripping surface, an outer cam surface and left and right side faces. Each segment also has an extraction hole in the front face thereof for receiving extraction tool fingers. On the left and right side faces of each segment is a lock recess extending from the front face of the segment and extending rearwardly towards the rear face. The lock recess comprises an enlarged portion and a narrow portion. The narrow portion of the lock recess opens into the respective side face of the segment. Each of the lock recesses cooperates with the lock recess on the adjacent side face of the adjacent segment.
    Type: Grant
    Filed: April 8, 1988
    Date of Patent: August 22, 1989
    Assignee: Hardinge Brothers, Inc.
    Inventors: Donald N. Terwilliger, Richard C. Knox
  • Patent number: 4799696
    Abstract: A pair of spindles are journaled coaxially one within the other in the indexing head of an automatic screw machine, and with the outer spindle disposed to be reciprocated axially between first and second limit positions in which it opens and closes, respectively, a collet which is supported by the inner spindle in the bore of the outer spindle. The outer spindle is urged axially to a collet closing position by a compression spring; and a camming element is rotatably adjustable about the outer spindle between a first position in which it urges the outer spindle axially rearwardly against the resistance of the spring to open the collet, and a second position in which it permits the spring to return the outer spindle to a collet closing position. The spring tension is adjustable by another element which is threaded on the outer spindle.
    Type: Grant
    Filed: December 30, 1987
    Date of Patent: January 24, 1989
    Assignee: Dover Industries, Inc.
    Inventors: Charles F. Reed, Valery Parker
  • Patent number: 4736957
    Abstract: A stressing arrangement for workpieces of cylindrical or at least partially cylindrical shape including a housing which coaxially surrounds the workpiece. For the purpose of temporarily fixedly holding the workpiece for further working, in particular for machining, stressing means are mounted in the housing. The stressing means include a pair of stress pincers, each one of which consists of a plurality of segments, and a pair of pressuring rings. The stress pincers and pressure rings have confronting conical surfaces adapted to coact with each other so that when the pair of pressure rings move apart a radial inward stress is imparted on the workpiece by the stress pincers. A plurality of stressing bolts are threadably mounted in at least one of the pair of pressure rings to selectively cause them to move toward each other or apart from each other.
    Type: Grant
    Filed: February 11, 1985
    Date of Patent: April 12, 1988
    Assignee: Rheinmetall GmbH
    Inventor: Klaus Bischopink
  • Patent number: 4604009
    Abstract: A tool retention mechanism is disclosed for clamping a tool holder knob. An elongate rod member is supported lengthwise in a compartment formed within the center of an elongate housing. A knob clamping assembly is mounted on the outer end of the rod member and is constructed of a circular array of claw fingers that are spring biased to urge them to move radially inward. A first piston is slideably supported on the actuator rod rearwardly of the claw fingers and has a cylindrical collar portion which slides over the claw fingers to retain them in a knob clamping position. A second piston is secured to the inner end portion of the actuator rod and slideably supported in the compartment to define a closed chamber with the inner closed end of the compartment.
    Type: Grant
    Filed: July 12, 1985
    Date of Patent: August 5, 1986
    Assignee: Illinois Tool Works Inc.
    Inventor: M. Richard Tennerstedt
  • Patent number: 4595363
    Abstract: A device for opening and closing a chuck for a dental handpiece has a handle portion and a powerhead assembly including a hollow driving shaft having, adjacent to its outer orifice, a forwardly outwardly tapering portion defining a small diameter rear portion and a large diameter front portion. A hollow cylindrical chuck has a forwardly outwardly tapering outer peripheral surface joining a small diameter rear surface and a large diameter front surface corresponding to the respective driving shaft portions. The chuck is slidably inserted into the driving shaft. Three radial openings are formed at equally spaced positions in the forwardly outwardly tapering outer peripheral surface of the cylindrical chuck. A plate-shaped chucking die having a concave bottom surface is slidably fitted into each radial opening to hold a dental tool.
    Type: Grant
    Filed: August 2, 1984
    Date of Patent: June 17, 1986
    Assignee: Nakanishi Dental Mfg. Co., Ltd.
    Inventor: Takasuke Nakanishi
  • Patent number: 4374481
    Abstract: The adjustable socket comprises a plurality of fingers pivoted by one end thereof to a socket body and enclosed within a partially rotatable shell covering the socket body. A spiral slot in the shell is engaged by a pin or the like extending from the body so that when the shell is partially rotated, the shell extends or retracts axially relative to the body portion thus opening or closing the distal ends of the fingers due to the engagement of the outer surfaces of the distal ends of the fingers with the curved inturned end of the shell. This shell and fingers can be detachably locked in the desired position. This enables the fingers to adjust in order to grasp or grip a nut or bolt within the size range governed by design parameters. A spring reacts between the shell and the body portion normally retracting the shell so that the fingers are in the widest position.
    Type: Grant
    Filed: June 10, 1980
    Date of Patent: February 22, 1983
    Inventor: Michael Brodie
  • Patent number: 4063488
    Abstract: An improved tool chuck having a draw-in rod axially movably located inside a tool spindle and attached to a locking head which is positively engageable with a tang on a tool. Locking members are provided and are each movably contained in radial openings in the wall of the locking head and adapted to be pushed by a control sleeve embracing the locking head into recesses in the tang of the tool. The locking members have circular-shaped segments thereon located to face radially inwardly with part of the circular edges being slidable in slots on faces having a complementary shape and being adapted to engage the tang at the end of the tool shank.
    Type: Grant
    Filed: February 7, 1977
    Date of Patent: December 20, 1977
    Assignee: Friedrich Deckel Aktiengesellschaft
    Inventor: Franz Kagerer
  • Patent number: 4014558
    Abstract: When the conventional feed yoke is moved forwardly by the conventional mechanism of an automatic screw machine, an internal conical surface on a ball sleeve, which is moved forwardly by the yoke, operating through balls forces the chuck-closing sleeve forward to close the split collet to grip and hold the bar stock firmly during a machining operation.
    Type: Grant
    Filed: March 8, 1976
    Date of Patent: March 29, 1977
    Assignee: Davenport Machine Tool Co., Inc.
    Inventor: Earl W. Brinkman
  • Patent number: 3992019
    Abstract: Core sampling drill head having powered drill chuck with jaws to grip drill rod. Head has thrust member movable by chuck actuating means between jaws retracted and jaws extended position, and precompressed chuck springs cooperating with thrust member and drill chuck so as to be movable with thrust member. Thrust member is located by releasable locking means in desired position, which means also relieve drill bearings of reaction from chuck springs. When thrust member is in jaws retracted position, chuck springs are precompressed by tension means and relatively large diameter tools can pass drill chuck. When thrust member is in jaws extended position, chuck springs cooperate with chuck, are further compressed and extend jaws to grip rod, and tension means are relieved of load from chuck springs. By precompressing and moving springs by themselves, worn drill rods can be accommodated in relatively short drill head without loss of grip.
    Type: Grant
    Filed: February 18, 1975
    Date of Patent: November 16, 1976
    Assignee: Canadian Mine Services Ltd.
    Inventor: Richard Crawshay
  • Patent number: 3937500
    Abstract: An annular member to be fitted around a small-diameter pipe has drawing means and pressing members. The drawing means connect the annular member to a large-diameter pipe, and the pressing members to the small-diameter pipe to thereby connect the small-diameter pipe and the large-diameter pipe together.
    Type: Grant
    Filed: June 18, 1974
    Date of Patent: February 10, 1976
    Inventor: Toshiyuki Sato
  • Patent number: RE37397
    Abstract: A circular flexible collet that provides a 360 degree gripping engagement with a cylindrical workpiece and which is operable by an actuator member incorporated in a workpiece chuck. The collet may be constructed as an internal collet for gripping engagement with a workpiece internal periphery, or as an external collet for gripping engagement with a workpiece external periphery. The flexible collet may be used for single, or plural workpiece gripping actions. The collet includes a split spring steel body having a radial opening split space and an outer and an inner circular periphery. One circular periphery is a workpiece gripping surface, and the other circular periphery has a tapered cam surface engageable by a workpiece chuck actuator member. The tapered cam surface has a plurality of circumferentially spaced apart slots, having an open outer end. In an internal collet the tapered cam surface is formed around the collet body inner periphery.
    Type: Grant
    Filed: March 25, 1999
    Date of Patent: October 2, 2001
    Inventor: Don R. Lloyd