Abstract: A coupling for transmitting a torque from a shaft to a hub provided with an internal chamber which can be pressurized and which is relieved when a relative rotational movement takes place in relation to the shaft due to an overload and which is secured against slipping off from the shaft seat in an axial direction by a two-part flange mounted on the shaft. The flange engages with a radial groove in the hub in a claw-like manner and carries a shear-off device for breaking off the plug sealing the internal pressure chamber.

Abstract: An apparatus for emergency locking of a lid for a glove compartment where the lid is pivotally attached to the opening portion of the glove compartment at the lower end thereof comprises an arm connected to the lid at one end thereof and inserted into an arm receiving hole formed in at least one side wall of the glove compartment. The arm has a first engaging portion disposed at the other free end thereof and engaged with the side wall when the lid is opened. The arm further has a second engaging portion disposed between both ends of the arm. A claw hook is disposed in the vicinity of the lower wall portion of the arm receiving hole and is capable of engaging with the second engaging portion of the arm to prevent the lid from being displaced in the opening direction thereof when the lid is pressed slantingly downwards.

Abstract: A method is provided of temporary assembling by soldering of peel off plates through soldering material and a flexible junction element for a mechanical release device to release two parts temporarily fixed edgewise by peeling off the flexible element and the soldering material. There is provided on the plates and flexible junction element reserve areas without any adherence to the soldering material, and preferably at the limits of said reserved areas a recess for removing any excess of soldering material, and the melting solder material is put under load for distributing it between the plates and the flexible junction element. A so obtained assembly can be applied particularly to obtain automatic opening of containers in particular in space for spreading out solar panels.

Abstract: A road sign attachment and repair apparatus having first and second U-shaped brackets adapted to be attached to a wooden sign post near the bottom thereof to form a resilient joint or to form such resilient joint at a place where a wooden sign post has been broken off. Four coil springs are attached to one of the U-shaped brackets at one end thereof and to the other U-shaped bracket at the other end thereof.

Abstract: A machine suitable for placement in a freezer for making slush or ice cream in a cylindrical container. The machine comprises a platform which is lengthwise adjustable, at least four rollers which have an adjustable distance support container, a driving means to drive the rollers and rotate the container, a scraping means disposed on the shaft of the container to scrape freezing slush or ice cream and to be used as a second safety means, and a first safety means which comprises a base plate, a control plate and a flexible element engaged together. When the slush or ice cream is hard enough, the control plate and the flexible element will rotate respective to the base plate so that the shaft will rotate together with the container. Further, even if the first safety means is out of order, the scraping means will free from the shaft of the container, then the scraping means will rotate together with the container in order to be used as a second safety means.

Abstract: A selectively preloaded coupling assembly 10 for connecting tubular members includes a tensioned annular member 12 including opposing coupling means 14, an annular recess 22 formed within the tensioned member and a tension maintaining annular member 26 seated within the annular recess.

Abstract: A banner support arm safety coupling rigidly mounts banner support arms to a pole and has a frangible or breakable portion so the coupling will break under loads on the banner before the pole fails. A safety line holds the coupling portion from completely separating after the frangible portion breaks.

Abstract: The invention provides an "on the fly" adjustable clutch for use with robot end-of-arm tooling that provides a means for sensing movement of a tool attached to the clutch and can send a signal to shut down the robot when an overload is encountered. The clutch includes a piston capable of lateral movement within a chamber that is slidably mounted on a pin and a tool plate. The pin extends beyond the clutch housing, and the tool plate is pivotally mounted on the pin. Biasing means acts to bias the piston away from the tool plate such that the tool plate is held somewhat rigidly in relation to the clutch housing by the biasing means. In a preferred embodiment, the biasing means includes springs and pressurized air that may be introduced into the piston chamber on either side of the piston to increase or decrease the bias of the springs. Thus, the clutch is capable of varying sensitivities with the biasing means being adjustable under program control.

Abstract: A fitting having a weakened section therein is positioned between a flow control device and a water outlet such as a sprinkler head so that if the sprinkler head is subjected to a lateral blow, the fluid conduit will break at the weakened section, but yet the flow out of the broken conduit will be restricted by the flow control device.

Abstract: A flangible ring, for securing together the adjacent flanged ends of the upper and lower barrel sections of a fire hydrant, has two weakening grooves therein instead of the usual one. One of the grooves is conventional and located in one face of the ring just inside the circular array of bolt holes in the ring. The other weakening groove is formed in the other face of the ring and is of greater mean diameter but of smaller, width and depth than the first groove. Preferably the sides of the other groove are straight in radial section, disposed at an angle of the order of 60.degree. to the face of the ring and an extension of the inner side thereof intersects the intersection of the bottom of the larger groove with a side thereof.

Abstract: A releasable coupling between a shaft and a hub is provided, which coupling includes a device operable by a pressure medium to produce a pressure lack between the shaft and the hub.

Abstract: A fastener system for securing workpieces together including a blind fastener located in aligned bores and when installed providing a preselected interference fit with the bores, the fastener including a pin and a sleeve with the pin having a shank with a sizing portion and expansion portion, the sleeve having a shank portion adapted to be pre-assembled onto the sizing portion and, while pre-assembled, having its outer surface reduced in diameter to a preselected magnitude such as to provide the desired interference with the bores when the expansion portion is moved therethrough.

Abstract: As a rotary pump, which is typically provided on an automobile, is provided with two alternative sources of motive power, typically including a driving connection to the automotive engine, and driving connection to an electric motor. These driving connections may be unidirectionally clutched in such a manner as to cause the electric motor to drive the rotary pump only when the pump is to be driven but the automotive engine is not operating up to a predetermined speed. Typically, the rotary pump is of the eccentrically mounted rotor type having radially outwardly protruding spring-loaded pistons effectively in contact with a camming ring. A slider is shown provided between the housing and the ring for effectively varying the magnitude of eccentricity of the rotor and thus for effectively smoothly varying the capacity of the pump.

Abstract: A vane assembly for a projectile has a carrier carrying a plurality of pivots, having at the pivots respective carrier elements, and adapted to be secured to an end of the projectile. Respective vane elements are each pivotal on the pivots between an inner position lying immediately adjacent the respective carrier element and within a projection of the projectile and an outer deployed position projecting beyond the projection. Respective heat-destructible pins engaged between the vane elements and the respective carrier elements normally retain the vanes in the inner position and release the vanes for movement into the outer position when destroyed by heat. The carrier element is a rib of the carrier against which the respective vane lies when not deployed.

Abstract: A swivel connector for connecting a first and second line for towing of one line by the other wherein there is provided an upper limit on loading that may be imposed between the lines as a safeguard to damage to one of the lines. The swivel connector includes first and second swivel heads connected by a load pin. The load pin is fixed to fracture at an approximate predetermined loading between the first and second swivel heads which loading is beneath that which would otherwise cause danger or damage to one of the lines. Upon fracture of the pin, it is readily replaced so that the swivel head can be used again.

Abstract: A frangible coupling assembly for breakaway pole bases has a pair of spaced and parallel plate with a plurality of struts extending therebetween and being situated between a pole base and a supporting base. Each strut is of an elongated cross-section with the longitudinal axis of the struts lying on the perimeter of a circle concentric with the central vertical axis of the plates thereby providing an increased resistance to torsional loads and at the same time relatively lower resistance to lateral force.

Abstract: A lubricant delivering coupling adapted to interconnect a power transfer unit and a load having a rotary input. The coupling is comprised of a pair of concentrically disposed inner and outer hollow members. The outer member is in a torque transmitting relationship between the power transfer unit and the load. The inner hollow member is secured at both ends to an inner surface of the outer member and is adapted to receive lubricant from a lubricant source within the transfer device for delivery to and through the hollow inner member.The inner and outer members each have intermediate the respective ends thereof a shear section. Upon overloading of the outer member and the shearing failure thereof, the inner member continues to twist until rupture at the inner member shear section.

Abstract: This invention relates to a rear view mirror assembly which facilitates installation of components of the rear view mirror assembly on a windshield of a vehicle. The rear view mirror assembly includes a first base member and a unit. The first unit includes a second base member, a spring, a mounting member, a second ball member, a bolt and a support arm on which a rear view mirror is rotatably mounted. The first base member has a plurality of flanges on which the second base member of the unit is mounted. The first base member is adhered to the windshield by an adhesive. In addition, the first base member is made of rolled stainless steel so that pores do not exist in a contact surface of the first base member. Therefore, air does not exist between the contact surface and the windshield, the air expanding and destroying the adhesive bond when heated by the sun. Further, the first base member preferably has a similar coefficient of expansion as that of the windshield.

Abstract: The invention comprises an improved end effector for a robot which is particularly advantageous in applications such as placing flat pack integrated circuits on circuit boards. The end effector includes a vacuum-operated quill for picking up the integrated circuit from a predetermined location. A pressure spring mechanism is included in the end effector permits the flat pack to be held in the desired position with a predetermined force by utilizing the robot arm to compress the pressure spring a predetermined amount. Once the integrated circuit is positioned on the circuit board, the circuit is released and the quill moved away from the board a predetermined distance by a linear actuator included in the end effector without any motion of the robotic arm.

Abstract: An energy absorbing guardrail terminal having a plurality of horizontally extending parallel guardrails on opposite sides of breakaway posts in which the guardrails have overlapping ends and the upstream ends are secured to the posts. Splice bolts connect the overlapping ends of adjacent rails and a plurality of spaced openings are provided in each rail horizontally aligned with each of the splice bolts whereby the impact of a vehicle on the upstream end of the rails will shred out the rail material between the spaced openings to absorb the kinetic energy of the impacting vehicle. Preferably the openings are slots elongated in the horizontal direction and the rails are staged to allow the upstream rails to telescope over the downstream rails.

Abstract: A weak point element for a cable head comprising a tubular ring having a circumferentially extending zone of reduced tensile strength between the ends thereof. Novel cable head assemblies which substantially isolate the weak point element from other than tensile stress are also disclosed.

Abstract: This invention relates to a rear view mirror assembly which facilitates installation of components of the rear view mirror assembly on a windshield of a vehicle. The rear view mirror assembly includes a first base member and a unit. The first unit includes a second base member, a spring, a mounting member, a second ball member, a bolt and a support arm on which a rear view mirror is rotatably mounted. The first base member has a plurality of flanges on which the second base member of the unit is mounted. The spring is mounted on the second base member. The mounting member includes a first socket portion and a first aperture. The support arm has a first ball portion which is slidably mounted on the first socket portion of the mounting member, and a second socket portion which is slidably mounted on the second ball member. The bolt has an end connected to the second ball member.

Abstract: A rigid rod is mounted between a pair of opposed wall brackets. At least one of the brackets is provided with an inverted U-shaped recess for receiving the end of the rod, and a pair of pegs extending cantilevered below the opening of the recesses. The pegs are spaced laterally a distance slightly less than the diameter of rod and are sufficiently rigid to hold the rod, with a normal complement of clothes, but also slightly flexible to spread apart and allow the rod to fall when the weight applied to the rod exceeds a predetermined limit.

Abstract: A breakaway standard support assembly has a base member, a standard member, and a coupler securing the base member to the standard member. The coupler has a coupler body assembly consisting of a plurality of body elements which are secured to each other and retained in such position by band means. The body element which cooperate to define the coupler assembly may be in mechanical interengagement. The coupler is sufficiently strong to support the static loading, normal wind forces and other forces encountered in normal use, but is adapted to fracture upon application of a horizontal impact load as by a vehicle, for example, so as to permit the stanadard to absorb shock and yet be moved out of its fixed position. The strap members may have weakened a portion such as a reduced thickness portion to facilitate fracture at a predetermined load level.

Abstract: Outriggers for sportfishing boats of the tubular mast type strengthened by a plurality of longitudinal truss cables to resist mast bending are improved by new spreader assemblies that include unique cable spreader arms that have (a) tubular sockets on their inboard end, (b) a cable guide through which an anti-bending cable passes removably fitted into their outboard end and (c) a frangible portion in the arm to break when the arm is overloaded. The improved spreader assemblies include (1) a collar, sized to encircle the mast and (2) a plurality of lateral posts, each threaded at one end into the collar and sized to slideably receive the tubular socket of one of the spreader arms to retain the arm extending laterally outwardly from the collar creating a cable truss member. The truss cables are connected to the mast via unique ball-anchor lugs formed as integral portions of the mast collars.

Abstract: A new type connector set is provided. Its male connector member includes a male housing having an engaging portion in the form of a nut. The female connector member includes a female housing with an opening to receive said male housing therethrough, a support member fixed within said female housing and having a chamber to receive the engaging portion of the male housing in it and a bolt rotatably extending within said chamber to be screwed into the nut. Said bolt is prevented from moving in an axial direction thereof and has a constricted portion in it.

Abstract: This invention relates to a rear view mirror assembly which can break away, when more then a predetermined force is applied to a rear view mirror. The rear view mirror assembly includes a base member and a first unit. The first unit includes a mounting member, a second socket member and a support arm on which the rear view mirror is rotatably mounted. The mounting member is mounted on the base member, and the mounting member has a first ball portion. The support arm has a first socket portion on an outer surface thereof, and the first socket portion is slidably mounted on the first ball portion of the mounting member. The support arm further includes a second ball portion on an inner surface thereof, and the inner surface is slidably mounted on the second socket member. The first unit is supported on the base member through a bolt and a spring. When a force is applied to the rear view mirror, the support arm can rotate on the mounting member and the first unit can rotate on the base member.

Abstract: This invention relates to a rear view mirror assembly which facilitates installation of the components of the rear view mirror assembly on a windshield of a vehicle. The rear view mirror assembly includes a base member, a spring and a unit. The unit includes a mounting member, a second ball member, a bolt and a support arm on which the rear view mirror is rotatably mounted. The spring is mounted on the base member, and the spring has a first engagement device. The mounting member includes a first socket portion and a first aperture. The support arm has a first ball portion which is slidably mounted on the first socket portion of the mounting member, and the support arm has a second socket portion which is slidably mounted on the second ball member. The second ball member has a protrusion which is disposed in a second aperture of the support arm.

Abstract: A main pump (rotary vane pump 1) and a secondary pump (radial piston pump 2) are driven by way of a common shaft (3), a cam ring (30) being used to drive the secondary pump. The cam ring is coupled to the shaft (3) by way of a shear pin (33). If the auxiliary pump locks, the shear pin fractures and the cam ring (30) can rotate relative to the shaft (3). In that case, the fracture portions of the shear pin (33) are driven into their respective bores (34, 35), thereby avoiding excessive friction and overheating. Therefore, the main pump can continue to operate in spite of the failure of the auxiliary pump.

Abstract: A break-away coupling for incorporation in a hoseline or pipeline, comprises a pair of tubular coupling members each being arranged at its one end for connection to a length of hoseline and provided at its other end with a face to be held in sealing engagement with a complementary face of the other member by frangible connectors. Each connector has one end length of spatulate shape and formed with a through opening to receive a shear pin, a screwed length at the other end to receive a nut, and an intermediate length of reduced section. Valve members in the coupling members are held in open positions against the action of springs until the coupling members are separated on breaking of the connectors; thereupon, the valve members close under spring action. A bleed passageway may be provided to prevent build-up of pressure between the complementary faces, and provide a seal testing facility.

Abstract: A break-away fence rail and support post for a horse race track fence is constructed to give way when impacted with a predetermined force so as to provide a yieldable barrier upon impact by a horse or jockey. Further, a fence for a race track constructed to provide a smooth non-abrasive surface without projections or discontinuities.

Abstract: In order to prevent expensive subsequent damage because of a shaft fracture in machines which are coupled together, one of the two shaft ends is provided outside of one coupling flange with a predetermined breaking point. At one coupling flange a safety element is mounted which extends past the axial length of the predetermined breaking point. The safety element can be constructed as a pin rotatably mounted inside the shaft end or as a safety ring mounted around the shaft end to hold a fractured shaft in the predetermined position until standstill without it being possible for the shaft to be deflected.

Abstract: A submersible motor pump assembly having an improved driving connection between the motor and pump. The motor shaft and pump shaft are disposed in end-to-end relation and a bolt extends through an axial passage in the pump shaft and the projecting end of the bolt is threaded in an axial opening in the end of the motor shaft. The outer or opposite end of the pump shaft is formed with a recess that communicates with the passage and the head of the bolt is fixed against rotation with respect to the pump shaft by a bolt retainer which is disposed with the recess. A shear pin interconnects the mating ends of the two shafts to provide a driving connection. The hand of the thread on the bolt is such that rotation of the motor shaft, after shearing of the shear pin, will cause the bolt to be unthreaded from the motor shaft to prevent locking up of the shafts.

Abstract: The valve is particularly designed compatible for use with toxic or highly flammable fluids. It has a hard valve stem tip, such as tungsten carbide which is pushed longitudinally against the valve seat and not rotated into sealing position. The valve is provided with a backseat threaded to the valve body so that if the bonnet or packing nut is very seriously abused by the operator even to the extent of twisting or breaking, the valve will not blow out toxic or flammable fluid. Most of the parts of the valve are made of stainless steel and provisions are made for lubricating the working parts of the valve. Notches in the valve stem and packing nut provide for a safe clean break of these parts in the event they are over stressed.

Abstract: The compressive force which the gripping means of a connector assembly, having a nut portion rotatably securable to a body portion, can exert upon a coaxial cable in limited to a pre-determined value by a frangible torque transmitting section, fracturable at a known shear strength, intermediate the body portion engaging section and the tool receiving section of the nut.

Abstract: A breakaway bail for a pedestal mount crane pivotally attached to the gantry by a pin extending through bushings secured to a pair of parallel plates with a spacer between the plates aligned with the bushings. A beam having an upright flange is secured between the plates and a multiple sheave pulley is attached to beam by brackets. Each of the plates has a necked down section between the flange and the spacer to create a high stress area, which area will separate under overload conditions without affecting the connection of the crane to its pedestal.

Abstract: In accordance with the present invention an industrial robot (10) having a lifting or gripping arm (16) is provided with electrical switch means (44) whereby if a work piece extends too far into the lifting or gripping portion the machine is automatically turned off. In accordance with another feature of the invention, shear means (54, 56, 58, 60, 62, 64) are provided in the lifting or gripping arms (30, 32) whereby if one or both arms abut an obstruction with sufficient force, the arm will shear off causing only minimal damage to the robot and protecting valuable gear mechanisms and control apparatus.

Abstract: In a composite aircraft formed of graphite reinforced epoxy plates forming walls of the aircraft and walls of fuel tanks therein, for example, there is an adhesive seal for bonding overlapping faying plate surfaces together. The seal is formed of spaced glass fibers mixed with a conductive material and impregnated with a resin. The resin is cured between the surfaces of the plates to which it is bonded. The conductive filler is carbon in the form of approximate microspheres, generally hollow and having diameters in the range of 5 to 150 microns. The carbon microspheres function to weaken the adhesive seal between the plates so that they can be forcibly separated by a wedge without structural damage to the plates. The conductive material equalizes negative and positive static charges in the aircraft, particularly in fuel tanks, to eliminate electrical potential differences in the wall structures and in the materials therein.

Abstract: In a composite aircraft formed of graphite reinforced epoxy plates forming walls (14, 16) of the aircraft and walls of fuel tanks (12) therein, for example, there is an adhesive seal (36) for bonding overlapping faying plate surfaces together. The seal (36) is formed of spaced glass fibers (58) impregnated with a resin and with a filler of conductive material (50). The conductive filler is carbon in the form of approximate microspheres (52, 54), generally hollow, and having diameters in the range of 5 to 150 microns. The resin is cured on the faying surfaces after they have been secured together by fasteners (28) coated with a dielectric (30). The carbon microspheres (50) function to weaken the adhesive seal (36) between the plates (16, 22) so that they can be forcibly separated without structural damage to the plates.

Abstract: A ground anchor for channel posts has an angle iron leg driven into the ground with a creased upright fin shroud strip or strap embracing the apex or corner of the angle iron at the trailing end of the leg and secured to the ends of the sides of the angle iron providing a V-shaped socket or barrel. The channel post straddles the angle iron with its side legs bottomed on the sides of the angle iron and a compression member bottomed on the strip forces the channel post against the angle iron to spread the legs of the post into tight gripping relation with the angle iron locking the post in the socket. The socket is open-ended and the post can slide over the angle iron leg to any desired depth so that a sign mounted on top of the post can be positioned at a selected height above the ground. The angle iron is driven into the ground to a depth sufficient to bury the shroud strip so that the post is the only portion of the assembly projecting above the ground.

Abstract: A device for coupling two rotary machines with provision for automatic uncoupling under certain operational conditions, comprising a first shaft and a second shaft in two parts which are connected for motion transmission in a first sense by a dog clutch connection and in a second sense by an intermediate co-axial shaft and transverse pins. In the first sense an accidental excess torque is limited by fracture of a frangible groove section disposed in the first shaft. In the second sense in which a substantially lower torque is exerted, this is limited by the fracture of a second frangible groove section disposed in the intermediate shaft. After fracture of this second groove section, the first shaft and one part of the second shaft will become spaced apart and the one shaft part is maintained in this position by a blocking mechanism comprising at one end a cylindrical bush accommodating a radial spring and balls which are displaced to an internal groove of the other shaft part.

Abstract: Belt clip assembly for use with a portable electronic apparatus includes a mounting bracket used to join a belt clip and a housing member. A mounting bracket is inserted through a pair of slots in a housing member and holds a belt clip in place by means of a pivot pin inserted through apertures in the mounting bracket and the belt clip. A pair of shear cuts adjacent the apertures in the mounting bracket allow the pivot pin to pull through the shear cuts in the event excess forces are applied to the belt clip, thereby destroying the mounting bracket. In this manner an inexpensive mounting bracket is sacrificed to avoid damage to the housing and the belt clip.

Abstract: The invention relates to an overload protection device for a machine tool, in which a carriage carried on the machine bed is displaceable, between the tailstock and the headstock by a lead screw [driven] by a drive motor and a feed gearing, and in which the lead screw nut is joined to the carriage by at least one joining bolt. To permit a very quick restoration of the machine to service after a collision between the carriage and a component present in its path of movement, while the predetermined dimensional relationship is restored without additional readjustment, the overload protection device is constructed such that the joining bolt has a break-away section in the area of the junction between the carriage and the lead screw nut.

Abstract: A safety belt coupling device which comprises components mutually attached by a heat degradable adhesive, such as a low-melting solder. At a predetermined temperature, degradation of the adhesive occurs, which allows the components to separate and thus release the safety belt.

Abstract: The present disclosure describes a latch assembly wherein structural members are coupled to each other by an electric match-type device interposed therebetween. The latter device generally comprises a body portion having electrical connections thereto and a rigid mass of combustible material firmly adhered to an extremity thereof. At least a pair of the structural members are individually coupled to the combustible material. Remote activation of the match by the passage of electric current therethrough results in the firing of the combustible material and the consequent opening of the latch through the elimination of the coupling force between the structural members.

Abstract: A cylinder for a valve actuator wherein the cylinder body has lugs connectable to and disconnectable from like cylinder head lugs by less than one turn rotation. Resilient seals seal the head to the body when connected, and the connection is releasably lockable.

Abstract: A low profile break safe breakaway system is described for mounting a post or the like in a vertical position on a footing. The system includes load concentrating elements on brackets disposed on opposite sides of the post to be supported. Breakaway members are provided which cooperate with the load concentrating elements and which are threadedly inserted into anchors which are embedded in the footing. The anchors include steel bar loops which extend downwardly into the footing and internally threaded elements at the upper ends of the anchors. Annular collars are provided at the upper ends of the anchor internally threaded members at the surface of the footing to prevent shattering of the footing concrete on application of bending moments of the coupling members.

Abstract: A frangible coupling utilizable in a sign assembly is provided, formed of a web having a through-extending opening and a plurality of through-extending slits extending outwardly from the opening and defining first and second web portions which will separate under impact loading. The terminations of the slits are short of the end of the web and provide out-of-plane tearing stress concentration. The coupling may be readily manufactured in a variety of manners, such as being cast or even being capable of being stamped. A method of stamping the coupling from a metal plate (e.g. steel plate) is also provided.

Abstract: A snowblower and a scarifying auger assembly for it which are characterized by a helicoid auger provided with scarifying teeth serially secured along its outer helical edge and each pivotally restrained by a shear bolt to scarify and easily plow and blow away the packed snow and for pivotal retraction of any tooth upon impact with an obstacle. The helicoid auger is thus relatively of essentially smaller diameter and protected by the scarifying teeth against impact of obstacles against it and against the ensuing expensive repair. Snow-throwing scoops are also arranged to be attached in different numbers and positions around the rotation axis of the helicoid auger.

Abstract: A sucker rod fitting for connecting together in an end-to-end relationship a plurality of sucker rods to form a sucker rod string for driving a pump in an oil well by an above ground oil pumping unit, the fitting comprising an elongated body having a central bore extending from an open end to a closed end, and the bore being defined at its end sections by cylindrical end walls, and between its end sections by alternately converging and diverging tapered sections which cause any breakage in a retained sucker rod to occur within the fitting.