Abstract: A holder for centered round articles comprises a frame having a first arm and a second arm pivotally attached thereto. The first arm defines a single contact point at its distal end while the second arm defines a pair of diverging surfaces at its distal end. The two arms are mechanically coupled to rotate relative to each other in a fixed relationship, and the curved surfaces on the second arm are shaped in a particular manner so that circular articles held by the two arms will be centered at a fixed location relative to the frame.

Abstract: A part gripping hand apparatus according to the present invention includes a body, drive motors disposed at three points on the body which are not on a straight line, arms integrally mounted on the drive shafts of the drive motors and extending from the center of rotation along radial directions with a predetermined length, finger members mounted on the ends of the arms, and a control unit for positioning and controlling the finger members at any position with the circumference of each of the finger members as the operation range.

Abstract: A picking tool for litter and the like includes a handle with a manually graspable upper end and jaw elements at the lower end which can be opened and closed by operating the handle to grasp material to be lifted. The handle includes two generally parallel handle sections which can be squeezed together by manual operation at the upper end. The squeezing action operates on a pair of gear tooth fulcrum members at the lower which are thus pivoted open by the squeezing action. Each fulcrum member can replacably receive a jaw element for grasping the material between the two jaw elements. One style of jaw element comprises a scoop. A second style of jaw element includes an outer pinch edge and a pair of receptacles rearwardly of the pinch edge for collecting materials of different sizes.

Abstract: A highly reconfigurable end effector employing three digits, each having two pivoting degrees of freedom and a rotational degree of freedom. The digits have an asymmetrical configuration where two of the digits rotate about an offset axis and the third digit about a substantially non-offset axis allowing the digits to reconfigure about a payload. Each digit employs a strong, tendonless digit actuation mechanism for driving the pivoting degrees of freedom. A differential transmission in the digit actuation mechanism, in conjunction with a double parallelogram configuration formed by the moving segments, provides a selective enveloping or parallel vise grip grasping action of the end effector.

Abstract: An article gripper has two cantilevered jaws biased together by a spring assembly to hold an article between arcuate surfaces of the jaws. The jaws are cantilever-mounted from respective pivot pins, and the article enters radially through an opening formed between the outboard ends of the cantilevered jaws. Between the pivot pins and the gripped article, the jaws have interengaging teeth which permit ease of engagement and disengagement as the jaws are pivoted, yet the teeth prevent unwanted sliding movement of one jaw past the other, as an article is located within the jaws.

Abstract: A mechanized container handling system on a motorized refuse collection vehicle includes a horizontally extensible and retractable support structure having an outer end on which a container grasping assembly is carried, and a container elevating and dumping assembly for lifting the grasped container and dumping its contents into an elevated hopper opening of the vehicle. The support structure comprises telescoped inner, intermediate and outer sections interconnected by an extension scissors structure, the intermediate section being horizontally driven by a hydraulic actuator and the scissors structure being operative to responsively extend and retract the outer section. The container elevating and dumping system is driven by a hydraulic piston and gear system positioned between the upper ends of a pair of support tracks and drivingly connected to a pair of articulated container lifting force arms.

Abstract: A vehicle having a flat bed for hauling a stack of open-top trash boxes. The vehicle also has a boom which can rotate about a vertical axis through an angle of 360.degree., and the boom is made up of relatively shiftable segments so that the effective reach of the boom can be changed from a minimum effective length to a maximum effective length. The outer end of the boom has a jaw structure to grasp a trash box at the center portion thereof to lift it off the bed or to place a trash box on the bed.

Abstract: Release device tied to underside of kite has rubber band-biased, cooperating jaws which releasably hold toy "paratrooper". Liquid-filled gelatin capsule serves as pin to hold jaws in closed position. Salt-water solution in capsule dissolves capsule, which causes jaws to open and "paratrooper" to be released from mechanism. Varying the concentration of the salt-water solution controls the amount of time delay before which the capsule dissolves and the "paratrooper" is released.

Abstract: An articulated hand comprising a plurality of finger module structures each of which has one top end provided with an abutting member for contacting an object and the other end connected to a finger connecting member and has a plurality of articulates formed between the one and the other ends by combination of a plurality of link members and articulate turn-shafts; a plurality of motors provided at the other ends of the respective finger module structures integrally therewith; a power transmitting device for transmitting motor powers to the articulate turn-shaft and a hand structure connected to a manipulator. The finger modules are arranged in a manner so that the articulate shafts are driven independently of each other, and each of the link members is provided with sensors respectively for directly detecting a relative angle and relative torque between adjacent link members.

Abstract: There is herein described an improved surface mounted component placement mechanism head structure which automatically accepts a very wide size range of such components.

Abstract: A modular dexterous grasping hand comprises three rotatable fingers mounted on the mounting plate of a Stewart platform for rotation about parallel axes extending perpendicular to the mounting plate. The fingers have a generally L shape so that the grasping elements at the distal ends of the fingers are spaced from the rotational axes. The grasping elements can thus be positioned along the arcs of circles centered on the rotational axes, and so form grasping triangles of variable shapes and sizes. The fingers are independently driven by motors mounted to the mounting plate. Positional encoders and pressure sensors may be included in the motor drive control system.

Abstract: A system for taking up and discharging ironed cloth articles from ironing apparatus comprises a column mounted on a base and supporting an articulated rotary arm at one end of which there is mounted a ball member for engaging an ironed cloth article and removing it from an ironing apparatus.

Abstract: The gripper is movable in a path transverse to the bobbin tube supports of the magazine to be aligned with a bobbin tube. The gripper employs gripping elements which engage a limited arcuate accessible portion of a bobbin tube under a force sufficient to extract the tube during movement of the gripper to a retracted position. After release from the gripping elements a transfer chute directs a bobbin tube to a receiving apparatus for subsequent delivery to a machine needing same.

Abstract: A pair of elongate arms, carried by a material handling device such as a refuse collection vehicle, are oppositely movable between a release position and a gripping position. The friction enhancing surface of a belt carried by each arm compliantly engages the perimeter of a container or similar article as the arms move to the gripping position. In response to movement of the arms to the gripping position, a limb pivotally carried by each arm extends to present a segment of the respective belt to engage the surface of a small container.

Abstract: A generally anthropomorphic prehensor having at least two mechanical finger apparatus which interface directly with an object being grasped by apparatus of mechanical linking and control mechanisms operatively connected to the operator's fingers. Each mechanical finger has at least two finger links adjacent one another, each finger link independently rotatable about parallel axes in a plane of movement in response to movements of the corresponding phalanges of the operator's fingers. The mechanical prehensor is particularly useful in hostile or hazardous environments.

Abstract: An improved robotic end effector is disclosed. The end effector of the present invention possesses a novel breakaway clutch, which is combined with mechanically linked finger joints to significantly reduce control complexity while retaining the ability to accomplish enveloping grasps. In another embodiment, a finger using compliant tendons to accomplish enveloping grasps is disclosed. A novel palm/finger configuration which further increases the versatility of the disclosed end effector without unduly increasing complexity is also disclosed. Methods of manipulating an object are also disclosed.

Abstract: A gripping tool (20) used in particular for the remote handling of connector plugs. The jaws (3) of a remote handled clip (1) chuck clamps (31). An intermediate mechanism (35) ensures the bringing together of two chucking parts (22) and (27) which makes it possible to ensure solid grasping in good conditions of a plug (10). The forces to be exerted for plugging are less significant and are transmitted more effectively.

Abstract: A robotic hand having a plurality of fingers, each having a plurality of joints pivotally connected one to the other, with actuators connected at one end to an actuating and control mechanism mounted remotely from the hand and at the other end to the joints of the fingers for manipulating the fingers and passing externally of the robot manipulating arm in between the hand and the actuating and control mechanism. The fingers include pulleys to route the actuators within the fingers. Cable tension sensing structure mounted on a portion of the hand are disclosed, as is the covering of the tip of each finger with a resilient and pliable friction enhancing surface.

Abstract: Pickup device (24) is for mounting on the mounting plate of a positioning robot. The pickup device has a frame (30) which carries movable carriages (36, 38). Cam ring (50) controls the position of the carriages. Downwardly depending arms (60, 62) carry pairs of levers thereon. The levers have facing sloped cam surfaces (84, 86) which are spread by downward thrust of closing pin 88. When the closing pin drops too far, it indicates lack of grasp and this is signaled by contacts (114, 116).

Abstract: A gripping device 10 for providing large moment-carrying capability for handling long cylindrical work-pieces W of a wide range of diameters. The device 10, which may be attached as an end effector for a robotic arm, includes two spaced pairs of parallel jaw type gripping members, 87, 102 and 101, 98. Each gripping member includes a gripping pad 110d with a contour which accommodates the grasping of cylindrical objects of different diameters. Movement of the gripping members between a fully open position (FIG. 3) and a fully closed position (FIG. 4) is controlled by a pair of concentrically arranged inner and outer output drive shafts 56, 59, each of which is provided with a pair of arms (81,82 and 83,84) extending in generally opposed radial directions of the shaft axis and to which a gripping member is pivotally attached near its distal end.

Abstract: A method of transporting an elongated object with a grapple includes placing the object in a generally horizontal position on a surface. The grapple is opened and placed about the object. The grapple is then closed about the object with a force sufficient to hold the arms of the grapple against the object, but insufficient to squeeze the object tightly between the arms. The grapple is raised with the object, and the object is allowed to swing between the arms of the grapple to a generally vertical position. The grapple may include two arms having pivotally interconnected inner ends. The arms have outer portions at the outer ends with edges directed towards the inner ends. The grapple has a closed position wherein the edges of the outer portions are perpendicular to an axis symmetry extending between the arms of the grapple.

Abstract: A gripping device which simulates the action of a human finger comprises three pivotted sections 3, 5, 7 having the middle section 5 linked to the tip section 7 by a bar 9 so that its rotation causes rotation of the tip section. Rotation of the lower section 3 is preferentially effected by a motor 11 via a sliding cross-head 15, an equalizer bar 18 and a rod 19. If this rotation is stopped by an object 25 to be gripped, the drive transfers via rod 20, crank 21 and rod 23 to the middle section 5, causing the middle and tip sections to rotate and grip the object against the lower portion as shown at 26. A robotic hand comprising four such fingers and a thumb is usable as a substitute for a human hand in a glove-box glove.

Abstract: A vacuum adsorption hand and a composite hand mechanism attachable to the arm or the like of a material handling industrial robot are disclosed. The vacuum adsorption hand includes a sponge-like element on the outer surface of a perforated plate defining a vacuum chamber to prevent the ports or perforations in the plate from being obstructed by packaging film on an article to be handled. The composite hand mechanism of the present invention includes grasping mechanisms for grasping the sides of an article to be held in addition to an adsorbing mechanism. The grasping mechanisms have first members adapted for transverse movement to apply an adjustable transverse grasping force and second members which are vertically movable with respect to the first members. The grasping mechanisms ensure that the article will be held securely despite the effects of horizontally-oriented forces acting on the article held by the composite hand mechanism.

Abstract: A workpiece handling device comprising a carrier mounting a plurality of pivot levers, each of which holds a clamping element. The pivot levers are pivotable about axes extending parallel to one another and their clamping elements are adapted to be synchronously moved towards and away from one another by a drive means common to all the pivot levers. In order to be able to move the clamping elements exactly in radial directions and in straight lines relative to the center of the workpiece and, at the same time, covering a large circular area, it is suggested that a clamping lever bearing the clamping element be articulatedly mounted on each pivot lever pivotable by the common drive means and that a pivoting device engaging each clamping lever be provided for pivoting the clamping lever in relation to the pivot lever in response to the pivoting movement thereof such that the clamping elements move in a manner known per se along straight lines intersecting at a center.

Abstract: A robot joint having a ball-like arrangement on a support, the ball arrangement positioned in a socket device in which the ball is free to move so the socket device can rotate in various directions about the ball arrangement. First and second connectors connect force imparting arrangements to fixed points in the socket device. One of these force imparting arrangements is capable of approaching or receding from the other in some rotations of the socket device.

Abstract: A gripping device for an apparatus for placing electronic and/or electrical components, in particular DIL components, on a substrate comprises a pair of grippers (1 and 2) which are movable towards and away from one another to close and open the jaws (4 and 5) of the grippers. To enable the device to handle components of different widths without the risk of damaging the terminal pins of the components, a stop member in the form of a vertically disposed stepped pin 12 is provided between the grippers for abutment by horizontally extending rib-like projections (8 and 9) on the inner sides of the gripper jaws to limit movement of the grippers in the closing direction.

Abstract: An electronic component insertion machine includes an insertion head having a pair of finger assemblies which grip a component prior to insertion. Each finger assembly has an actuating lever secured to a pivot shaft and a finger holder releasably clamped to the pivot shaft. The actuating levers have surfaces which are maintained in engagement throughout their displacement so that rotation of one effects a conjoint rotation of the other and are displaced to advanced positions. The finger holders are then unclamped, oriented to their desired orientations relative to their actuating levers and then clamped in position.

Abstract: An industrial robot hand for material handling. A fixed frame is connected to an arm of an industrial robot. A movable frame having a rectangular plan shape is horizontally movably supported on the fixed frame. Two guide rods are vertically attached to each of the four sides of the movable frame. A tapered guide extends downwardly from each of the guide rods. Sandwiching plates are provided on two opposite sides of the movable frame. Each sandwiching plate is pivotally attached to the movable frame by a horizontal axis at the central portion of the sandwiching plate. Engaging members project inwardly from the lower inner surface of the sandwiching plates to hold the material to be handled. Rollers and roller guides restrict the movement of the movable frame on the fixed frame. A driving mechanism pivots the sandwiching plates to bring the engaging members into engagement with the material.

Abstract: A gripping device for an apparatus for placing electronic and/or electrical components with terminal pins on a substrate comprises a pair of grippers (9 and 10) which are movable relative to one another by fluid-pressure operated means to close and open the jaws (12 and 13) of the grippers. The force for driving the pins of a component into the respective holes in the substrate is applied to the component through abutment means which are self-adjustable to accommodate differences in the heights of the components so that the gripper jaws can be brought to a constant level at the pick-up position each time and can be arranged to grip the component over areas which extend to the bottom of the body of the component to facilitate accurate positioning of the terminal pins in relation to the respective holes in the substrate when mounting the component.

Abstract: Mechanically operated collet chuck for gripping round objects. Especially in automatic, program-controlled installations for the successive machining of round workpieces, a centered gripping of the round objects, which are changing in diameter, is important. The centering error occurring in case of a collet-carrying machine which remains stationary is compensated for by means of link quadrilaterals (3, 8, 10, 12) which latter cause collet jaws (9) pivotably mounted to the front ends of the collet arms (4) and forming four contact points to pivot with respect to the collet arms (4) in such a way that the contact points or contact lines come into contact with the round object (1) simultaneously, without a change in position of the machine or of the round object.

Abstract: A spare rib holder consisting of two oppositely disposed members pivotally joined at one end to simulate retractable jaws, the members being spring biased with respect to each other so as to normally be in open position, the free ends of both members being provided with oppositely disposed teeth for grasping a spare rib therebetween, the lower member having a ramp projecting forwardly therefrom for leading a spare rib to the jaws.

Abstract: A gripper and wrist joint assembly for a robotic arm. The gripper comprises a pair of identical jams connected by a pivot and including V-sections for holding large objects and end-mounted pivotal tips for holding small and flat sided objects. The jaws are opened and closed by rotation of a screw-threaded rod having screw threaded connections with the jaws, the axis of the rod being fixed and the pivot pins being guided with linear displacement during adjustment of jaws so that they are maintained central within the gripper housing. The wrist includes a pair of spiroid level gears driven by respective spiroid pinions and each meshing with an output bevel gear carried on a shaft equipped with an adjustment nut for engaging the bevel gears into firm engagement and enabling backlash to be eliminated.

Abstract: A power tool for auto body repair in accordance with this invention, including several species or embodiments of this invention, comprises a small hydraulic ram which may be as small as two inches or less in height, width and length with a reciprocating piston or ram having a travel of less than an inch between its extended position and its retracted position. One embodiment of the tool includes an iron to press out wrinkles in metal auto body parts, comprising a pair of pivotally joined levers each having a press plate at the working end, pivotal between an open position to receive a wrinkled auto body part and a closed position to iron or press out the wrinkles, the small hydraulic ram being positioned between the opposite or power end of the levers to force the working end to its closed pressing position when the hydraulic piston or ram is moved toward its extended position.

Abstract: A hand tool (40) is provided for removing a cover (2) from a package (4), such as an electronic circuitry package, having respective adjacent facing surfaces (22) and (23) on opposite sides thereof. Tool (40) has a pair of spaced-apart resilient arms (8) and (10) having respective free-ends (14) and (16) provided with jaw members (24) respectively having a lip (18) operative to engage surface (22) and provide support for cover (2) and are further adapted to provide a wedging action between surfaces (22) and (23) effective to urge cover (2) away from package (4) when arms (8) and (10) are contracted towards each other. Arms (8) and (10) are additionally provided with resilient biasing means (26) on facing surfaces effective to prevent lips (18) from engaging surface (22) when arms (8) and (10) are in a relaxed condition to facilitate removal of cover ( 2) from tool (40) and to impart a biasing force F.sub.c against opposite sides (20) of cover (2) when arms (8) and (10) are contracted towards each other.

Abstract: A fruit gripper head assembly for use in a machine for pitting fruits of the drupe type includes a support structure receivable onto a pitting machine, a plurality of gripper arms spaced about the central axis of the assembly and mounted on the support structure for pivotal movement toward and away from the central axis, and fluid pressure operated actuating apparatus operatively connected to the gripper arm and to the support structure for urging pivotal movement of the arms toward the central axis upon introduction of pressurized fluid behind that actuating apparatus to provide for pivotal movement of the arms to grip fruit to be pitted.

Abstract: A robotic gripper assembly having a pair of gripping fingers inserted through a slotted disk, each of which is coupled to a cam groove formed within a cam disk wherein longitudinal finger movement is effectuated along the slotted disk. The closing rate and resolution of the finger movement with respect to cam disk movement are easily changed by interchanging the cam disk. In another embodiment, a three finger configuration is provided wherein the gripping fingers move longitudinally through intersecting planes for handling irregularly shaped objects.

Abstract: A robot hand gripping device intended for equipping the end of the wrist or arm of an industrial robot or robotized appliance, comprising grasping members or fingers and hydromechanical controls for spreading the grasping members apart from one another and/or bringing them closer to one another. It is formed by assembling together two identical parts with an intermediate piece between the parts, connectors being provided in the intermediate piece for connecting the two identical parts to at least one drive-energy source, such as compressed air, oil or the like.

Abstract: A piston-operated robotic gripper system has gripper means including a piston mounted within a cylinder for movement between a first position and a second position, with the piston operatively linked to move grasping means between a first retracted position and a second extended position corresponding to the first and second piston positions, respectively. Conduit means are connected to first and second sides of the piston to introduce pressurized fluid into the cylinder on the first side of the piston to cause the piston and grasping means to move to their first positions and to introduce pressurized fluid into the cylinder on the second side of the piston while exhausting the fluid from the cylinder on the first side of the piston to cause the piston and grasping means to move to their second positions.

Abstract: A positive indication of the closure state of a fingered gripper is provided by a sensor having a first element mounted for motion responsive to the primary finger driver and a second element operable in conjunction with the first element to provide, between the two, a positive indication of the gripper state.

Abstract: An apparatus (23) is constructed having a pair of side gripping members (32, 34) which are pivotally coupled by hinges to an intermediate gripping member (36). These gripping members (32, 34, 36) have a l/d (length-to-diameter) ratio of approximately 5:1 to distribute compressive forces over a relatively large area. Inner gripping regions (46, 48, 50) of the members (32, 34, 36) are configured having frictional surfaces (46, 48, 50) which frictionally grip a tubular structure, such as a bi-stem (12). A latch (51) having catches (56) is positioned on one of side gripping members (34), and a catch (62) is positioned on the opposite side member (32) for engaging the catches (56), latching the apparatus (23) closed around the bi-stem (12). Handles (68, 70) are centrally affixed to an exterior region of side members (32, 34) and allow the apparatus (23) to be readily closed around the bi-stem (12) and also allow manipulation of the bi-stem (12).

Abstract: An end effector device (A) for grasping and holding an article such as a handle (18) of a space telescope is disclosed. The device includes a V-shaped capture window (74) defined as inclined surfaces (76, 78) in parallel face plates (22, 24) which converge toward a retainer recess (54) in which the handle is retained. A pivotal finger (30) meshes with a pair of pivoted fingers (26, 28) which rotate in counterrotation. The fingers rotate to pull a handle within the capture window into recess (54) where latches (50) lock handle (18) in the recess. To align the capture window, plates (22, 24) may be cocked plus or minus five degrees on base (64).

Abstract: A gripping device for gripping an outer peripheral edge of an object to be grasped such as, for example, a semiconductor wafer, with the gripping device including a base, gripping members for gripping the object to be grasped, elastic members disposed between the base and the grip members so as to urge the respective grip members in an opening or closing direction. A driver for the grip members is provided, with the driver being fashioned as a linear or flat shape memory alloy member which is connected across the grip members.

Abstract: Locator device for locating modular electronic components centrally with respect to a nozzle of an apparatus for attaching the components to a substrate, such as a printed circuit board. The locator device comprises a component support member for supporting a component to be located centrally with respect to the nozzle of a component attachment apparatus, and a component centralizing element associated with the component support member and engageable with the nozzle for centralizing the component with respect to the nozzle prior to soldering of the component to the printed circuit board. When the component has been centralized with respect to the nozzle, the component is maintained in its centralized position by attachment to a source of vacuum disposed within the nozzle. This facilitates removal of the locator device from the nozzle to leave the component disposed centrally within the nozzle attached to the source of vacuum and ready for installation on the printed circuit board.

Abstract: A robotic hand consisting of one or more jointed fingers each formed from a number of link elements. A torque control is supplied for each element so that undue pressure is not exerted by any link element on an object being gripped. The invention provides an electromechanical simulation of a human hand, flexing to encompass objects rather than impinging against them.

Abstract: Apparatus for safely lifting a roll of material having a horizontal eye is disclosed. The apparatus consists of a tong having horizontally relatively movable lifting legs which each include lifting decks to engage the roll's eye. Sliding members are provided to yieldingly address the roll ends and to move horizontally and vertically during closing of the lifting leg under the control of a dampening means. Additionally, the sliding members are maintained stationary with the roll during movement of the tong to engage the eye with the lifting decks to avoid scraping of the roll ends. A spring means is provided to return the sliding member to its rest position following the release of the displaced rolls.

Abstract: A preform transfer mechanism for transferring preforms from an oven to a mold station includes a support frame, a slide block mounted on the support frame and an elongated transfer bar fixed to the slide block. At least two sets of jaw assemblies are positioned on the transfer bar. A jaw actuating rod engages the jaw assemblies to open and close them. An overtravel plunger carried by the rod permits independent closing of each jaw assembly to accommodate different diameter preforms. A set of preform locators or baskets are mounted on the support frame for receipt of heated preforms from the oven.

Abstract: Apparatus for use in grabbing a refuse container such that the container can be emptied into a refuse collection truck. The grabbing apparatus includes a pair of opposed articulated grabbing arms which have the capability of securely grabbing containers of substantially different sizes without crushing or otherwise damaging those containers.

Abstract: The present invention is a grapple for orienting track rails. The grapple includes a front tine and rear tine arcuate in shape and pivotally secured to a bottom end of a frame and depending therefrom to tip ends. Each tine defines an inner concave surface, and the tines are mounted to the frames so that the concave surfaces face towards each other. The front tine includes a knob portion integral with its tip end that extends outwardly from its inner concave surface towards the inner concave surface of the back tine. The tines are operated by a pair of hydraulic cylinders, and each tine includes a plurality of gear teeth extending from the end thereof that is secured to the frame. The gear teeth are enmeshed and provide for coincidental opening and closing of the tines by operation of the hydraulic cylinders. The knob portion of the front tine provides for cooperation with the ball portion of the railroad rail for orienting the rail into a desired upright position.

Abstract: A salt block carrier includes a handle with a pair of pivotally mounted arms movably secured to the handle. The arms each have an end designed to fit and hold the salt block with blunt gripping knobs.

Abstract: The invention relates to gravity-closing tongs for handling steel ingots, slabs, and similar products. The tongs include two legs, each of which has two arms which are supported, in a tongs housing, on pivots disposed horizontally and transversely to the plane in which the tongs legs move. The lower arms of the tongs legs are provided with gripping pins or similar devices, and the upper arms are hinged to links of equal length. An adjusting device permits axial displacement of the tongs pivots and an accumulator intensifies the force with which the tongs gripping pins are applied. In order to minimize the investment for intensifying the contact pressure of the tongs gripping pins and to mitigate impacts or shocks on the drive of the adjusting device(s), the accumulator includes two horizontally acting force-accumulating elements (compression springs) which are each arranged between the upper end of the corresponding tongs leg and the extreme end of the corresponding link.