Abstract: A process for the manufacture of a tubular fabric such as stockings and the like having a closed toe by knitting same on a circular knitting machine having two needle beds in which two layers are formed when reaching the toe, the two layers then being twisted relative to each other through at least 180.degree. and then joined by a connected course so that a welt is formed whereby the stocking is more comfortable.

Abstract: Two or more warp-knitted members of a tubular or cylindrical shape are interconnected by a connecting thread to provide reinforcement to be inserted longitudinally in a row of helically coiled fastener elements. The tubular warp-knitted members may be wrapped around core members. A choice is available of diameters of the warp-knitted members so as to be compatible with the particular shapes and contours of given fastener elements. A plurality of warp-knitted members are interconnected in such a fashion that the resulting reinforcement can be adapted for securing a relatively large-size fastener element onto the tape.

Abstract: Sealing device for the continuous inlet and outlet of textile material in the form of endless ropes into and from a pressure-tight container under high temperature conditions, consisting of a number of locks of graduated pressure, which are positioned one behind the other in the transport direction of the rope, and characterized in that each pressure lock is a sealing element made of elastic material in the form of the common shell of two frusta of straight circular cones of different height, which abut on each other axially with their top faces, and which face, in the direction toward the open base of the lower frustum the room under higher pressure, and whose internal surface is lined with a smooth layer and the inner diameter of the sealing element approximately corresponds to the diameter of the cylindrically shaped textile rope, so as to be tightly pressed from all sides onto the textile material under the action of the higher internal pressure exerted in the pressure container on the outer shell of the

Abstract: A printed fabric washing apparatus comprises a U-shaped tunnel-like cage, a tank in which the cage is disposed for vertical movement and a ridge-like projection mounted on the bottom transversely below the cage, a fabric introduced in the cage being washed and travelled in a tensionless condition by the water repelled at the ridge-like projection as a result of the up and down movement of the cage.

Abstract: One or more containers of dye liquor under pressure are connected by a supply line carrying dye liquor from each container to a dye fixture on which are successively positioned rolls of knit tubular fabric which is to be deknit subsequently to form textured yarn. A plurality of generally parallel, spaced tubular elements having spaced dye outlet openings therein are so arranged to form a horizontal support surface with the dye openings facing upwardly toward the exposed side of the knit tubing roll. Dye liquor from each container is carried through one of the supply lines into a corresponding header or manifold. The tubular elements are so arranged to be connected to one of the headers. A control valve in the supply lines is selectively activated to cause a surge of pressure in the tubular elements so that a plurality of spaced jets of dye liquor are emitted through the openings onto or into the adjacent side surface of a knit tubing roll positioned on or near the upper surface.

Abstract: In a popular form of changeable combination padlock there is a pivotally mounted, spring urged blocking lever whose lower end portion is pivotally associated with the clutch elements for the dialing wheels and whose upper end portion engages a pair of shackle locking bolts when the shackle is retracted and locked holding the locking bolts in a so-called "dead-bolt" condition. The last mentioned portion of the blocking lever is free to move, however, within a cavity in the lock case and bolt housing to disengage and release said locking bolts when the permutation mechanism is correctly operated for shackle unlocking purposes. In a changeable combination padlock of the type under consideration the cavity within the case wherein the upper portion of the blocking lever can move, is relatively commodious.

Abstract: In a padlock having a plurality of peg housings in cylindrical form and opening onto a side surface of the padlock, a common width for closing all of the peg housings, which lid on its inside surface carries a plurality of projections, each for insertion into a peg housing and means for holding the lid to the padlock body.

Abstract: A single cylinder deadbolt lock with a thumbturn includes a slidable pair of gear elements normally engaging the thumbturn with the cylinder whereby either one will operate the bolt. One such gear element is provided on a hub rotatable with the locking bar shaft, while the other gear element comprises part of the thumbturn mechanism. A rotatable sleeve coaxial with the locking bar shaft is also normally disposed in meshing engagement with the aforementioned hub but is restrained from axial movement. Axial movement together with rotation of the lock cylinder, e.g., for locking the mechanism, moves the hub and the sleeve out of meshing engagement, causing the hub and thumbturn to be held out of meshing engagement for disabling the thumbturn until the cylinder is again rotated.

Abstract: A key controlled lock for electrical switches, etc., in which a rotatably supported plastic switch actuator element is provided with a substantially diametrically extending keyway at one end to receive a key. Locking fingers of a plastic yieldable locking device normally engage in opposite side of the keyway. The key, upon insertion in the keyway, cams the fingers outwardly to release the actuator element for rotation by the key.

Abstract: A releasable, reusable, tamperproof device for attaching an anti-theft monitor to an article of merchandise is disclosed. The attachment device includes a tack adapted to be passed through the monitor and the article and into a keeper. The keeper encloses a one-way fastener of the type having opposed legs defining surfaces for gripping the pointed shank of the tack. Compression of the opposed legs to a releasing position permits withdrawal of the tack. In accordance with one embodiment, the keeper includes openings through which rotatable key means are insertable for engaging and displacing the legs to the tack-releasing position. In another embodiment the keeper incorporates flexible diaphragms dividing the keeper into a pair of side chambers separated by a central chamber enclosing the one-way fastener. Pressurization of the side chambers deflects the diaphragms into engagement with the fastener legs and causes displacement thereof to the tack-releasing position.

Abstract: As a part to be contour formed passes through the rolls of a pyramid roll forming machine, the vertical position of the upper roll is continuously controlled. Specifically, upper roll position feedback signals are summed with position command signals and the resultant position error signals used to control hydraulic actuators. The hydraulic actuators, in turn, control the position of the upper roll. In an elongate pyramid roll forming machine (e.g. one designed to contour panels or plates) both ends of the upper roll are controlled such that the axis of the upper roll may be skewed with respect to the axes of the lower set of pyramid rolls, or lie parallel to the axes of the lower rolls. In such a machine the positions of the ends of the upper roll are continuously controllable as a part is being contour formed. In a narrow pyramid roll forming machine (e.g.

Abstract: A method of making a pipe fitting havin three or more legs arranged in any desired shape by deforming a malleable metal tube substantially filled with a constant volume filler material in a single step without the need for secondary bending while maintaining the filler material at constant volume to provide a fitting wherein the variation in wall thickness is less than about 10%.

Abstract: An automatic metal-spinning machine utilizing a plurality of work spindles, which rotate on their own axes, adjacent respective parallel spinning-tool operating shafts rotatable with variable pressure to apply tools against workpieces on the spindles while all simultaneously and continuously rotate around a central column so that a plurality of metal blanks are progressively formed and several parts are completed as the spindles and tool operating shafts make one revolution around the central column.

Abstract: Device for rolling rolling-contact bearing races from a blank by means of a die and shaping wheels comprising an inner roller for obtaining the internal profile of the race in the die from which it is separated to permit a possible extrusion of the excess material of said blank, and an outer wheel for shaping part of the external profile of the race against the action of the inner roller, said die being divided in the axial direction into two separable sections disposed on either side of said outer wheel in a die support and constituting a cavity of which the profile is designed for shaping the portions of the outer profile of the race which are adjacent to those shaped by said roller, the two die sections being fitted for free rotation in said die support.

Abstract: A forming tool comprising a rigid frame, clamping jaws on the frame for clamping a hollow tube with the end to be formed in a position of alignment with a forming head mounted on the frame for linear movement toward the end of the clamped tube and for rotation about the axis of the tube, said clamping jaws containing an opening for receiving the forming head as it is advanced into engagement with the tube, and said forming head containing a fustrum conical forming cavity for engagement with the end of the tube within which the end of the tube is wholly formed. A pilot is provided within the forming cavity for maintaining the concentricity of the tube and forming cavity during the forming operation. The entire surface of the forming head is coated with a non-electrolytically applied surface coating of nickel.

Abstract: In the uncoiling and straightening apparatus of the invention, the leading edge of the uncoiled strip material is caused to pass through a straightening machine which is supported for pivotal movement on a horizontal axis so that the machine may be moved to and from horizontal and inclined positions. The shaft providing the horizontal axis also supports a roller and the strip material is caused to contact the roller when the straightening machine is operating in an inclined position. Also to facilitate the uncoiling and bending operations on the material, a stripping apron and a back-breaker roller are incorporated in the apparatus, with the said stripping apron having pivotal movement on the said horizontal axis.

Abstract: A method of deep embossing of sheet material, generally metal, is disclosed. A small scale relief pattern is first embossed across the entire sheet and thereafter a deep embossment of spaced-apart protuberances is imparted to the sheet. Both patterns in combination produce a sheet useful for reflective thermal insulation without the risk of significantly puncturing the sheet.

Abstract: Machine for simultaneous reduction and straightening of metallic tubes or rods has a reducing die which is mounted in the frame downstream of a guide for workpieces and upstream of a ring-shaped straightening tool whose axis orbits about the axis of the opening in the die. The outlet end of the internal surface surrounding the opening in the die tapers counter to the direction of lengthwise movement of workpieces through the die. The guide insures that the workpieces cannot be flexed upstream of the throat portion of the internal surface of the die, and a second guide can be provided downstream of the straightening tool to confine the flexing of the workpieces to the region between the throat portion of the internal surface of the die and the second guide. The tool is mounted in a spherical bearing which is installed in the eccentric bore of a sleeve driven by a pulley to rotate about the axis of the die whereby the tool orbits the axis of its passage about the axis of the opening in the die.

Abstract: This invention provides a method and apparatus for expanding spiralweld pipe. The expander head is cantilevered at a fixed location and the spiralweld pipe is advanced in stages around the expander head, moving in the direction of the pipe axis. At each stage, the pipe is stopped, and the expander head is expanded to cause expansion in the pipe. The expander head has on its surface a helically arranged recess matching the main weld of the pipe. As the pipe is moved between adjacent expansion locations, it undergoes axial and rotational motion so that the main weld tracks in registry with the recess.

Abstract: A press adapted for use in confined areas for swaging a sleeve onto reinforcing bars to splice them together. The press comprises a cylinder having a longitudinal axis with a piston therein and reciprocable along said axis, said cylinder having an end and a pair of spaced arms extending from said end in a direction generally parallel to said cylinder, with the distance generally between the outer surfaces of said arms measured in a direction transverse to said longitudinal axis being less than the outer diameter of the cylinder. A bridging member is detachably secured to and bridges the arms. A first die part is secured to the free end of the piston and a second cooperable die part is secured to the bridging member. The die parts cooperate together to swage the sleeve onto the bars by the movement of the first die. piece toward the second die piece in accordance with the movement of the piston along said longitudinal axis.

Abstract: Apparatus is disclosed for calibrating a cigarette inspection device, whereby known defects, such as perforations, are placed in the wrappings of certain cigarettes as they pass through the cigarette inspection device, including a test drum for receiving the cigarettes to be inspected and associated with a pressure-responsive device to be connected successively to the interior of each cigarette at a test point, as it is moved about upon the periphery of the drum past the test point. In operation, a calibration control circuit is actuated to place a defect, in the form of a perforation, into three test cigarettes. Defects, of a magnitude greater than the acceptable limit, are placed in the first and third test cigarettes, and a defect within the acceptable limit is placed in the second test cigarette.

Abstract: A filled or gas encasing element to be tested is placed in a measuring chamber. The free space between the element and the chamber is filled with filler elements to prevent bursting or inflation of the element. A vacuum is produced in the chamber, and the time required to achieve a predetermined pressure increase therein is measured.

Abstract: A leak detector for checking leakage of passageways in automotive engines which applies a pressure to a passageway and detects leakage, the detector including two parts which seal opposite sides of a passageway and a connecting member which extends through the passageway and sealably holds these parts in place.

Abstract: Apparatus comprising a conveyor adapted to move a plurality of test receptacles along a given path. Spaced along the path are means for adding a test fluid to the receptacles; first means for checking a desired parameter of the test fluid; means for inserting a cell; second means for checking the fluid for changes after a sufficient digestion period; means for comparing the two readings; and means for removing the cell. Additional means can also be provided for emptying the test fluid and rinsing the receptacles.

Abstract: A testing device for measuring a lateral pressure induced on a material by a vertical applied pressure, the testing device comprising in combination a material-holding receptacle which is capable of lateral expansion in response to a vertical applied force on a material contained in the receptacle, and a sensing means positioned on the receptacle to sense the amount of lateral expansion of the receptacle.

Abstract: A sonic nozzle apparatus in a carburetor flow testing machine comprising a measuring pipe passage connecting a carburetor to be tested and a pressure source such as a vacuum pump or the like, the measuring pipe passage being provided at an intermediate portion with a cutout section in which a tubular nozzle chamber can be selectively introduced in sealed relation. A plurality of such tubular nozzle chambers are mounted on a turntable to be selectively introduced into the cutout and each nozzle chamber contains a respective sonic nozzle therein. The nozzle chambers are disposed circumferentially at regular intervals and the turntable is intermittently turnable on a support shaft disposed on one side of the measuring pipe passage. One of the mutually opposite surfaces of an upstream and a downstream portion of the measuring pipe passage divided by the cutout is constituted as a piston which is movable by a pressure fluid to selectively effect clamping or release of the nozzle chamber when aligned in the cutout.

Abstract: A vibration isolator of the type used for mounting industrial equipment, having the capability of measuring forces exerted upon the isolator to adjust the support provided by each of the isolators upon which the equipment is mounted so as to provide the most suitable distribution of support and to reduce the transmission of dynamic forces created by the operation of the equipment. The isolator comprises a resilient base, a bearing plate on the base and a sensing device cooperating therewith, with or without means for attaching the isolator to the equipment. A force applied to the isolator exerts pressure on the bearing plate which is transmitted therethrough to the resilient base causing each of them to experience some deformation. The sensing device detects the pressure or deformation caused by the force applied to the isolator and generates a signal corresponding to said force.

Abstract: The proposed force measuring transducer with a frequency output signal comprises an elastic body arranged in a casing in spaced relationship with said casing. The elastic body, which is subjected to the action of a force, has a base and a working member. The base is secured in the casing with the aid of at least three supports. One end of each support is tapered and bears up against the surface of the base, whereas the other end of each support is joined to the casing. The working member is connected to an oscillating element whose oscillation frequency is dependent upon the action of the force. The oscillating member is the resonator of an electromechanical self-excited oscillator.

Abstract: A method of forming a continuous film of an elastomeric latex and a phenolic resin comprising spraying a plurality of coats of the aqueous admixture onto a nonadherent surface. The nonadherent surface is at a temperature of 120.degree. F. or greater and each coat of the aqueous admixture is less than about 0.7 mil dry film thickness. The film so formed can be tested for physical properties and the testing results are capable of being correlated with the performance of glass fibers with the aqueous admixture coated thereon for reinforcement of elastomeric matrices.

Abstract: A self-contained, battery powered well logging instrument is pumped down the interior of a drill pipe string having a catcher sub at its lower end. When the logging instrument latches into the catcher sub, the pumped fluid circulation is blocked, after which increased pump pressure switches a valve assembly to recreate circulation and energize the logging instrument to the standby position. An accelerometer in the logging instrument detects the upward movement of the instrument and switches the circuitry from standby to the record mode. The output from a clock controlled by the downhole accelerometer is recorded along with the logging information and is synchronized with pipe footage measurements and with a similar such accelerometer and clock at the earth's surface which are responsive to the movement of the pipe string at the earth's surface. The recorded logging samples are thus related to true depth by correlating with the data simultaneously recorded at the earth's surface.

Abstract: Disclosed is an pitot-static tube whose sensed pressure is converted to a variable resistor setting, the resistor being series connected to a thermistor adapted to respond to outdoor temperature. A D.C. voltage is impressed across these elements in series with the coil of an indicating meter which is calibrated to indicate the wind chill factor or index determined by the temperature and wind magnitude sensed by the thermistor and pitot-static tube, respectively.

Abstract: A bluff body flowmeter, including a bluff body having a planar base surface portion disposed normal to fluid flow and a pair of converging downstream surfaces, is provided with a fluid flow channel in the base surface portion, a sensor in the channel and a shield which partially covers the channel and protects the sensor from impact damage. The shield and channel are mutually adapted so that fluid flow through the channel is substantially unidirectional. In one embodiment at least that portion of the shield which covers the channel is shorter than the channel thus forming a rectangular notch which acts as a fluid flow entrance port.

Abstract: A vortex type flowmeter having a body member, a cover member and an interior varying diameter cavity formed in the body member in which fluid is introduced to flow in a generally helical pattern within the cavity, the fluid being introduced at the periphery of the cavity having the largest diameter and the fluid exiting from an aperture at the center of the vortex formed by the helical flow. The flowmeter includes a toothed rotor mounted for rotation within the cavity and the flow of fluid causes the rotor to rotate within the cavity at a rotational rate which is generally directly related to the velocity of flow. The flowmeter is provided with a light-emitting diode and photosensitive transistor combination which senses the passage of each of the teeth as the rotor is rotating within the cavity. This combination is formed as a unitary assembly, a portion of which nests a portion of the rotor.

Abstract: A device for monitoring the amount or depth of silage or similar material retained in a silo or like structure is disclosed. A number of sensors are vertically arrayed in and on a silo wall, and each sensor senses the presence or absence of silage in its immediate vicinity. An electrical circuit includes a visual display device such as a liquid crystal display for indicating the amount of material in the silo.

Abstract: Temperature sensing apparatus utilizing a single temperature sensing diode which is supplied with a constant level of current. The voltage across the diode having the constant current therethrough is compared with a constant voltage reference in a summing means and the deviation of the sensing diode with respect to the constant voltage reference is utilized as an indication of temperature.

Abstract: The measuring detector is constituted by the resistance of a given volume of doped semiconductor, there being formed on one face of a semiconducting monocrystal a surface region having a well-determined thickness and a well-determined concentration of doping ions and two electrical contacts at the extremities of said region.The doped surface region is obtained by ion implantation and there is formed on the second face of the monocrystal a metallic coating which has good thermal conductivity and is in good thermal contact with said second face.The detector is primarily applicable to thermometric measurements at very low temperatures below 1.degree. K.

Abstract: Continuous row average sampling of a stationary source gas stream is accomplished with the aid of a tubular sampling probe extending across the gas stream flow path in a transverse plane of the path and having sampling port means forming a longitudinally extending sampling port row through which gas is drawn into the probe. The sampling port means preferably comprise one or more ports spanned by a porous filter medium and are designed to produce a pressure drop which is substantially uniform along the port row and relatively large in comparison to any internal or external pressure changes which occur along the probe so as to maintain a uniform gas sampling rate along the port row.

Abstract: Liquid quantitative dispensing apparatus for withdrawing liquid like a syringe into a plurality of pipettes arranged in rows, by simultaneously pressing and releasing cap-like projections formed of flexible material and dispensing the liquid to test tubes and the like.

Abstract: A linear accelerometer comprises a proof mass in the form of a permanent bar magnet located in a tube containing a magnetic fluid such as a liquid with particles of magnetic material suspended therein. A servo circuit responsive to A.C. energized sensing coils is used to energize a D.C. electromagnet to maintain the proof mass in a central position in the tube.

Abstract: A starter for a rope pull outboard motor that may be quickly and readily attached to the top of the motor housing. The device includes an outboard motor rope pulling member that can be spring-loaded by a manually operable means after which the handle of the outboard motor rope may be connected to the rope pulling member. Novel guiding means is used for the rapid movement of the rope pulling member to quickly pull the rope to start the motor when the spring biased rope pulling member is freed. A shock absorber brings the rope pulling member to a resilient stop at the end of the movement of the member.

Abstract: A mechanical counterbalance assembly for an overhead, track mounted, aircraft door includes a frame, a shaft mounted for rotation in the frame, and a torsion spring interconnected between the shaft and the frame. As the shaft is turned in a first direction, the spring is wound so that a torque is applied to the shaft in the direction opposite to rotation. The spring rate of the torsional spring is selected so the spring torsional force slightly exceeds the component of the door weight acting along the path of motion of the door throughout the door travel. A cable drum is mounted for rotation on the shaft and is releasably affixed thereto. A cable is wrapped about the drum and has its free end connected to the overhead sliding door. A planetary gear train has its low speed input shaft coupled to the shaft and its high speed output shaft operatively coupled to a centrifugal brake and to a manually rotatable drive wheel.

Abstract: The invention concerns a device for adjusting the rotational speed of a drive mechanism preferably of the type used in a movie projector and provided with a drive motor having a stationary fixed stator, a rotor rotating in only one direction and connected to a friction wheel with at least one, preferably two, oppositely disposed friction discs fixed on a drive shaft for driving engagement with the friction wheel, the friction wheel being adjustable with respect to the friction discs in a radial direction to thereby adjust the rotational speed of the driving mechanism.

Abstract: This variator is improved in order to improve reliability and prolong its life.For this purpose it comprises a friction elements clamping plate provided with two cylindrical skirts which axially extend from opposite sides of the plane of the clamping plate and enable the clamping plate to be supported by the housing by bearings which are axially spaced apart and located on opposite sides of the plane of the clamping plate. Moreover, a ring carrying ramps which adjust the clamping force exerted by the clamping plate in accordance with the torque transmitted is connected to the clamping plate by a relatively deformable connection so that the clamping plate is not subjected to a particularly harmful alternating tipping.

Abstract: A synchronous belt and pulley drive in which the drive between spaced pulleys is primarily by frictional contact of a belt on the pulley peripheries; synchronization is insured by providing spaced teeth on the belt which teeth are accommodated by tooth gaps in the periphery of the pulleys. The drive is further characterized by matching the pitch of the driveR pulley with the belt pitch under a first tension and matching the pitch of the driveN pulley with the belt pitch under a second tension, wherein the first tension is different and usually greater than the second tension.

Abstract: A demand driven clutch which constitutes an improvement over Jensen U.S. Pat. No. 3,369,765 and Treise U.S. Pat. No. 3,695,534 and which includes a pair of cooperating driving elements, one of which constitutes a driving collar fixed to the rotary drive shaft and the other constitutes a driving hub connected to said collar by stress distributing axially disposed connecting elements to maintain the circular configuration of the outer clutch surface of said hub for uniform engagement with the circular inner clutch surface of the spring spool pulley member.

Abstract: An endless power transmission belt is provided which has a compression section and a plurality of longitudinally extending ribs comprising the compression section and defining the inside surface of the belt and each pair of immediately adjacent ribs has a space therebetween with the space allowing wear of the ribs while assuring the apexes of sheave projections operatively associating with the belt are maintained spaced from the belt thereby prolonging the life thereof.

Abstract: An improved mechanism is provided for biasing a driven gear in a gear train of the variable center distance type in which the driven gear is meshed with a drive gear and rotates about an axis which is not fixed, at least radially, relative to the axis of the drive gear. The biasing mechanism includes spring means engaged with the driven gear for biasing the same substantially radially toward the driven gear into mesh therewith at a force which provides appropriate relatively low-level engagement forces between the meshed gear teeth. A stop is provided for limiting deflection of the spring means in a direction corresponding to unmeshing of the drive and driven gears. The stop is positioned to limit such deflection of the spring means to an amount less than the deflection required for unmeshing of the gears.

Abstract: Head for a robot or manipulator comprising a control casing and at least two shafts perpendicular to each other, with corresponding external members rotatably driven from separate control servo motors, one shaft being rigid with one of said members which supports the other shaft, said servo motors are fixedly mounted in said casing so as to drive at least two coaxial shafts, while the driving of at least one of said perpendicular shafts from one of said coaxial shafts takes place through a bevel gear of which the input pinion is rigid with this one coaxial shaft and the output pinion is rigid with the shaft concerned.This head construction permits assembling the servo motors into a readily accessible unit by providing said coaxial shafts with concentric toothed members in meshing engagement with driving pinion driven in turn from said servo motors, and is applicable notably to robot heads having two or three degrees of freedom.

Abstract: The invention relates to gear drives. The globoid worm gearing comprises a cylindrical worm-wheel in mesh with a globoid worm. The side surfaces of the thread of said globoid worm are shaped so as to envelop the side surfaces of the worm-wheel teeth with the result that in the process of successive engagement of the worm thread with the worm-wheel teeth the worm thread makes a linear contact throughout the side surface of the worm-wheel teeth. Said globoidal gearing is capable of transmitting larger torques and possesses a greater kinematic accuracy than like-size modified globoid worm gears known in the prior art.A method of making the globoid worm is provided whereby the worm is generated through relative movements of the worm blank and a rotary cutter and thereafter the side surfaces of the worm thread are finished by honing. The cutting edges of the rotary cutter are located on a generating surface having the shape of the side surfaces of the cylindrical worm-wheel teeth.

Abstract: A safety steering-wheel has a rim situated in front of a central hub of the wheel. Only two legs are fixed to the rim and are inclined therefrom rearwardly toward the central hub, these legs when projected onto a plane which contains the rim extending along radii of the latter which are situated relatively close to each other. At least one of these legs is fixed to the hub. Fixed to the hub or at least one of the above legs is a substantially gallows-shaped complementary portion which is situated in the vicinity of the hub, with this complementary portion situated behind the plane of the rim but forwardly of the hub. The above legs and complementary portion when projected onto a plane which contains the central axis of the hub form a substantially V-shaped configuration, the crest of which is situated adjacent the hub, the complementary portion being inclined oppositely to the legs and extending to the side of the hub axis opposite from the legs.