Abstract: A flex joint is disclosed for connecting two cylindrical instrument housings of a downhole instrument assembly that will bend as required to allow the instrument housings to move through a curved section of a well bore. The joint includes spaced tubular connectors for connecting the joint to the cylindrical housings. The connectors are connected by a flexible cable or thin walled cylindrical tube. One or more helical springs extend between the connectors and are held in compression to urge the connectors toward an in-line position while allowing the joint to bend as required for the cylindrical instrument housings to travel through a curved section of a well bore.

Abstract: A wiper device for a vehicle includes a pair of left and right pivot brackets. The pivot brackets are pivotably attached to a vehicle body through a pair of left and right elastic members at left and right mounting points, respectively. The wiper device has a connecting member for connecting the left pivot bracket with the right pivot bracket. A wiper motor unit includes a wiper motor and an unit bracket for mounting the wiper motor. The unit bracket is attached to the vehicle body through a center elastic member at a center mounting point shifted from an imaginary line passing through the left and right mounting points. Further, the unit bracket of the wiper motor unit is positioned on the connecting member so that a gravity center of the wiper motor unit rides on the imaginary line.

Abstract: A steering column support having a bracket on the steering column secured to vehicle support structure by fasteners at the rear edge of the bracket. Isolator pads at the front edge of the bracket are clamped under pressure between the bracket and the support structure The isolator pads dampen vibration of the steering column and also prevent undesirable tilting or rocking of the steering column when the vehicle is in motion.

Abstract: A coupling device for linear drives for linking a drive part performing a linear movement in an axial direction with a guide part guided for longitudinal movement on a longitudinal guide parallel to the direction of movement. A force input part connected with the drive part and a force output put part connected with the guide part are provided, the force input part and the force output part being coupled together kinetically by means of an intermediately placed link member. As a link member and a elongated or longitudinal spring member is provided which is able to be bent in at least one transverse direction in a resiliently elastic manner and is non-yielding in its longitudinal direction, said spring member being aligned at least substantially in the axial direction. It is secured at a first connection point to the force input part and at a second connection point spaced from the first connection is connected with the force output part, in each case non-movably in the axial direction.

Abstract: A floating pin joint is provided for coupling a linear potentiometer to a machine for measuring relative movement between first and second component parts of the machine. The potentiometer has an elongated housing securable to the first component part and a drive actuator slidably attached to the housing. In one embodiment, the floating pin joint includes a bushing, an actuator rod and a spring. The bushing can be positioned in a mounting hole on the drive actuator with an annular bearing surface disposed at one end of the bushing facing outwardly from the mounting hole. The actuator rod has a flange disposed between a first end and second end which contacts the bearing surface when the second end of the rod is extended through the bushing. The spring attaches to the second end of the rod for maintaining the flange in contact with the bearing surface.

Abstract: A vehicle safety pedal apparatus includes a foot engaging portion, a linkage attachment for attaching the pedal apparatus to a vehicle, a pedal linkage coupled between the linkage attachment and the foot engaging portion including first and second sub-linkages and a shock absorber coupled between the first and second sub-linkages to absorb shock during a collision of a person's lower extremity with the pedal apparatus during a motor vehicle accident, the shock absorber including a sleeve on the first sub-linkage forming a cavity, and a pin, the sleeve further including through aligned apertures and the second sub-linkage further including an elongated aperture, the apertures of the sleeve aligned with the elongated aperture, and the pin extending through the aligned apertures, thereby providing limited slidable engagement of the sub-linkages, the cavity containing a resilient shock absorbing material that is capable of restoring its shock absorbing capacity after absorbing an initial shock.

Abstract: A single shear joint is provided which includes a conical ferrule establishing a nesting means of engagement with controlled embedment between a link and a mating component.

Abstract: A stabilizer bar bushing adapted to receive a metal stabilizer bar and to be secured within a mounting assembly that is attached to a vehicle frame for cooperatively resisting excessive sway when a vehicle is turning and a method of manufacture. The stabilizer bar bushing includes an elastomeric member and a low coefficient of friction film layer. The elastomeric member has an outer diameter, an inner diameter defining a bore and a slot extending the longitudinal length of the elastomeric member from the outer diameter to the inner diameter. The low coefficient of friction film layer is adhered to the inner diameter and the slot to facilitate ease of insertion of the stabilizer bar within the bore and reduce frictional engagement of the elastomeric member with the stabilizer bar.

Abstract: Cantilever shafts (34, 40) support bearing assemblies (54, 56) over which is mounted a tuned compliance or constraint member (92) including flexure members (102, 104, 106) which minimize deflection of the shafts and improve operation of associated rotary tools (18, 20). An improved lock nut (70-86) permits precise installation of the bearing assemblies.

Abstract: A flexible shaft in which the interior rotating cable is formed of links having first and second loops formed of wires or bands that have a maximum diameter slightly less than the inside diameter of the outer non-rotating shell. The second loop of one link is linked to the first loop of the adjacent link to provide a very flexible shaft or cable with a minimum of friction.

Abstract: A connecting rod used for a multiple chamber compressor pump comprises a central section having in the main surface thereof an opening for receiving therein a bearing for an eccentric of the multiple compressor pump, at least two pushing sections, and respective hinge areas arranged between the central section and the pushing sections and generating restoring forces, when the pushing sections are deflected relative to the central area.

Abstract: A flexural pivot bearing includes a pair of members with opposed close-spaced faces which are joined by a web (29), of microscopic thickness, in a plane intersecting the faces. These members and the web are comprised of an integral body (27) of substantially uniform material, and the members are adapted for pivoted mutual flexure about a pivot axis aligned along the web.

Abstract: A flexible coupling device including a flexible metal rod or wire within a flexible tube which can be removably secured through the aligned bores of the pieces. The pieces are held in a fixed longitudinal relationship using the axial tension created by the flexible coupling device while still permitting relative rotation between each of the pieces. The flexible metal rod or wire is secured through various mechanism which include radial angular ridges in the interior of the flexible tube and a retaining post having radial angular ridges that interlock with the ridges in the flexible tube such that, as the post is inserted into the flexible tube, the post ridges and the tube ridges interlock to secure the flexible tube. In addition, radial angular ridges on the exterior of the flexible rod interlock with a retaining post having an interior bore with corresponding radial angular ridges as the flexible rod is inserted into the retaining post.

Abstract: A connector and method for interconnecting separate frame members to form a display frame which does not require the use of tools for the assembly or disassembly thereof. The connector includes a first plate, a second plate spaced-apart from the first plate, and a resilient spacer retained between the first and second plates which are each disposed within ends of the frame members. The spacer is formed from a resilient non-setting material which expands between the first and second plates to permit the first and second plates to be frictionally retained within the frame members.

Abstract: A rear fender of a motorcycle, particularly a racing motorcycle, is securely connected to the cross frame under the motorcycle seat. The rear fender includes a front portion, a flexible center hinge, and a rear portion. The front portion is fixably connected under the motorcycle seat with the rear portion free to rotate about the hinge. The front portion can be of any desired length in order to fit the various models of motorcycles.

Abstract: A fastening system for securing modular panels to an underlying support structure. The fastening system includes a number of pad members, preferably made of foamed material, secured to the underside of each panel, and a saw-like apparatus carried by the pad members for severing the pad members from the vehicle structure. One side of each of the pad members is secured to the panel underside. The other side of each pad member is secured to an appropriate location on the vehicle structure in such a manner that the outer surface of the panel, when the panel is properly secured on the vehicle body, lies flush with the outer surface of the vehicle body.

Abstract: An advertising display mounting device is provided for attaching promotional displays, dispensers, or other objects to a price channel mounted on the edge of a grocery or other retail store shelf. This mounting device uses clips which are adapted to mate with the price channel of the shelf. The clips are forced into a mated relation with the price channel by a locking slide. The invention also provides for a means by which to attach an advertising display to the advertising display mounting device.

Abstract: A plastic joint for articulating two components comprises two dimensionally stable fastening elements serving for connecting the plastic joint with the corresponding component and a joint element arranged between the fastening elements defining at least one joint axis for deflecting the joint out of its straight position. The joint element is formed as a flexible moulded part which is injected directly with its ends to the fastening elements.

Abstract: A flexible tie strut for supporting both compressive and tensile forces, the flexible tie strut including a tension member and a coaxially mounted compression member, the compression member and the tensile member being interconnected at their respective ends. A coupler for interconnecting struts, and a system of couplers and struts are also disclosed.

Abstract: A protective cover for a ball joint assembly includes a plurality of arms. The arms are movable between a retracted position and an extended position in which the arms can be manually grasped to pull the cover off of the ball joint assembly. The cover is one piece and has a side wall with cylindrical sections and an end wall. The arms are mounted on the end wall. When the arms are to be moved from the retracted position to the extended position, the end wall of the cover is pressed against the end of the ball stud to flex the end wall and move the arms from the retracted position to the extended position.

Abstract: A relatively inexpensive coupling for preventing the transmission of thread drunkenness to a carriage or other element being driven by a lead screw. The coupling is formed with an input plate and an output plate both connected to an intermediate member. The connections via flexure members permit movement of the intermediate member relative to the coupling and the output plate to provide uniform motion to a carriage along the lead screw axis.

Abstract: A shear plug connector arrangement is formed by a bearing element (1) and a plug element (2) that can be introduced into the bearing element. The bearing element (1) comprises an outer sleeve and an inner sleeve (3 and 4, respectively). Between these two sleeves (3, 4), an elastic element (5) is arranged. The inner sleeve (4) and thus the plug element (2) introduced therein are mounted in floating fashion. This leads to a good footstep sound insulation. In accordance with the invention, a structure (7, 8, 9) is provided for limiting motion amplitudes at the bearing element (1) and/or at the plug element (2) so that the elastic element is not subject to excessive stresses and to ensuing short-term or long-term damage. The aforementioned structure is realized, for example, by an annular disk (8) on the front face of the inner sleeve (4), a nail plate (7) having a circular opening at the outer sleeve (3), and an interposed gap (9).

Abstract: An advertising display mounting device is provided for attaching promotional displays, dispensers, or other objects to a price channel mounted on the edge of a grocery or other retail store shelf. The advertising display mounting device has first and second clips adapted to mate with the price channel of a grocery or other retail store shelf. The clips are forced into mated relation with the price channel by a locking slide. First clip means is provided having a plurality of teeth. Second clip means has a slot formed therein for accepting first clip means so that first and second clips are oriented parallel to each other and to the price channel. A channel formed in second clip means accepts a locking slide, also having one or more teeth for cooperating with the corresponding teeth on first clip means. As locking slide is forced into the channel, first and second teeth mesh and move the first clip relative to the second clip to lock the mounting device in the price channel.

Abstract: A mechanical rotary coupler for first and second coral shafts having slotted ends proximate one another, the coupler being formed of an elongated blade of resilient material longitudinally slit and folded on itself transverse to the slit to provide first and second resilient V-shaped strips connected by bridging portions at the ends of the blade, the strips respectively being adapted to engage the slots in the ends of the first and second shafts at regions on the strips spaced from the bridging portions.

Abstract: A pipe joining construction includes a tube, two or more extensions extended from the tube, a tube member coupled to each of the extensions so as to form a joint portion, an insert disposed in each of the tube members and the extensions and having an envelope and a foamable material disposed in the envelope, a covering having an outer layer wrapped around the joint portion and a foamable material disposed between the outer layer and the joint portion. When foamed, the foamable materials apply forces against the tube members and the extensions so as to solidly couple them together.

Abstract: A unitary construction device for temporarily attaching an object to a support of generally elongate shape along a reference axis, has a first part attached to the support and a second part attached to the object and joined to the first part by a coupling portion flexible in bending. This coupling portion includes a pair of identical axial tangs aligned on a first line transverse to the reference axis and coplanar therewith, flexible parallel to a second line transverse to the reference axis and perpendicular to the first transverse line, and requiring the same energy to fracture in tension parallel to the axis. The coupling portion further includes at least one pair of first feet attached to the first part, one on each side of the first transverse line and extending axially towards the second part, and at least one pair of second feet attached to the second part and extending axially towards the pair of first feet and separated therefrom by the same predetermined axial distance.

Abstract: A coupling fan includes a fan body, a coupling and a mounting plate. The mounting plate includes a substantially ring-shaped base member and a substantially strip-shaped movable member having spring elasticity. The base member is connected to a boss of the fan body or an operating member of the coupling. The movable member is connected to the base member at its one end, and it is further connected to the boss of the fan body or the operating member of the coupling, to which the base member is not connected, at its another end. With this construction, not only vibrations of the fan body and the coupling are absorbed by the movable member, but also an overall inside diameter of the mounting plate can be made greater. Namely, a coupling having a larger outside diameter can be employed, and accordingly the cooling efficiency of the coupling can be improved. Hence, the coupling fan can be improved in its durability.

Abstract: A coupling fan includes a fan body, a coupling and a mounting plate. The mounting plate includes a substantially ring-shaped base member and a substantially strip-shaped movable member having spring elasticity. The base member is connected to a boss of the fan body or an operating member of the coupling. The movable member is connected to the base member at its one end, and it is further connected to the boss of the fan body or the operating member of the coupling, to which the base member is not connected, at its another end. With this construction, not only vibrations of the fan body and the coupling are absorbed by the movable member, but also an overall inside diameter of the mounting plate can be made greater. Namely, a coupling having a larger outside diameter can be employed, and accordingly the cooling efficiency of the coupling can be improved. Hence, the coupling fan can be improved in its durability.

Abstract: The invention is directed to a spring joint having two holding bodies. The spring joint is fixedly attached to a base at one of the holding bodies. The second holding body is provided for the attachment of a component which is intended to undergo a pivot movement relative to the base during operation. A spring element acts as a connecting body between the two holding bodies. A stop is mounted on the spring joint so that the spring joint can be used again after impact loads or intermittent vibration. This stop includes at least one stop body which limits the movement range of the spring body in the spring joint for radial and axial load to the elastic range.

Abstract: A coupling 1, 50, 100 for joining adjacent frame members 2, 3 of a fish breeding enclosure 5 comprises a first mounting means 10, 52, 105, 106 for mounting to one frame member 2, a second mounting means 11, 53, 105, 106 for mounting to another frame member 3 and a flexible body 12, 51, 101 of elastomeric material between the first and second mounting means 10, 11, 52, 53, 105, 106. The coupling 1, 50, 100 constrains relative rotational and translational movement between the frame members 2, 3 in use to a predetermined level which is determined by the material of the flexible body 12, 51, 101 and/or by mechanical limit stops 62, 63. A non flexible connection such as a rod 35 having flanges 36, 37 or a chain 90, 110 provides a mechanical connection between the mounting means 10, 11, 52, 53, 105, 106 in the event of failure of the flexible body 12, 51, 101.

Abstract: In this arrangement, each of two elements, namely a support element and a flow control element forms on at least one of its two outsides part of a flow control surface. A joint element couples the flow control element movably to the support element and is arranged at a distance behind the flow control surfaces. The support element and the flow control element have in the area of the joint element, end faces that face each other. These define a space which is filled up by a soft and elastic filler piece.

Abstract: There is disclosed a bending device for use in an endoscope or the like. The bending device includes an articulation assembly constituted by a number of segments. In order to increase the rigidity of the articulation assembly in its radial direction, each segment has such a simple configuration that the segment can be formed by bending a hard metal plate such, for example, as a hard spring metal. More specifically, the segment has a semi-cylindrical portion and a pair of extension portions extending respectively from opposite circumferential ends of the semi-cylindrical portion in a direction of the circumference of the semi-cylindrical portion. A pair of notches are formed respectively in opposite axial ends of the segment at the boundary between each of the opposite circumferential ends of the semi-cylindrical portion and each of the extension portions.

Abstract: A robotic wrist employs a plurality of elastomeric containers holding an electro-rheological fluid. An electromagnetic field can be selectively applied across the electro-rheological fluid within these elastomeric containers to selectively control the viscosity of the electro-rheological fluid and thereby control the stiffness of the elastomeric containers. Two sets of elastomeric containers can be used to control both the axial and radial stiffnesses of the wrist. In the preferred embodiment, the elastomeric containers have a hollow spherical shape. An electromagnetic field is created within the containers by applying a voltage between a conductive film on the interior surface of the sphere and second electrode extending through the sphere into the electro-rheological fluid.

Abstract: A rubber-metal bearing element 1 comprises two parallel washers 2, 3 interconnected by a rubber block 4, from which extend threaded bolts, 5, 6 for screwing the bearing elements to the parts 9, 10 to be joined. To prevent the threaded bolt from being entrained by the nut 12 with the latter is tightened, the washer 3 is concave inwards so that only its circumference is in contact with the part 10. The friction torque between the washer 3 and the part 10 is greater than between the nut 12 and the threaded bolt 6. The nut 12 can therefore be tightened, without entraining the threaded bolt, until the washer 3 is flattened against the part 10.

Abstract: A resilient shaft coupling in which a rigid primary and a rigid secondary coupling member are connected together by at least one resilient annular assembly of a multi-part construction that is composed of a number of ring segments that are identical and run circumferentially in close succession. Each segment is composed of axially outer metallic segment plates and an inner rubber body that has a trapezoidal cross-sectional shape with a radially outwardly increasing width in an axial plane. In order to obtain higher thermal stressability of the shaft coupling, at least one window is provided in the rubber body of each segment. The ends of the window end in the vicinity of the radial end faces of the segment. Openings are also provided in the two segment plates of each segment and are congruent with the window in the rubber body.

Abstract: A supporting device including a first member which supports a springy means for resiliently supporting a second member. The supporting device includes a detection for detecting displacements of the springy with respect to the first member in accordance with the movement of the second member and a biasing which applies a force to the springy from the same direction as or from a direction opposite to that of the displacement for changing the elasticity of the springy in accordance with the movement of the second member.

Abstract: A chair which includes a seat frame having depending leg members and a pair of upstanding, spaced apart members arranged to provide a lower backrest part for the chair and an upper backrest frame part having a pair of spaced apart depending members in registry with the upstanding members, said members being hollow with open extremities, and flexible spring means secured between each pair of members to provide an articulated, flexible spring backrest for the chair. Each flexible spring means includes an elongated, flat or blade spring member having its opposite ends secured within a holder member which is closed at one end and open at its opposite end for inserting the spring into the holder. The open ends of each holder have stop flange formations protruding outwardly thereon which, when the holders are spaced apart at their open ends with a slight gap therebetween, effect limitation of the angle of flexure of the spring by engagement of the flanges one with the other.

Abstract: A structure to be subjected to bending and fatigue loading comprises two components having different stiffness connected together. Deflection of the more flexible component is accommodated by the interposition of an intermediate member of varying flexibility between the components or by providing the less flexible component with a flexible portion to act as a fulcrum for the deflection. The components may be a radar-transparent cover and a mounting therefor for use in a submarine.

Abstract: At least one torsion spring is traversely mounted between first and second elements of an overload protector. One end of the spring is elongated to form a pressure arm which bears against the second element.

Abstract: The coupling of the present invention is used for joining two shafts together. The coupling comprises a first hub and a second hub which are joined together by a central web located therebetween. Both the first and second hubs include an inner bore extending therethrough and an outer tapered surface. The bores of the first and second hubs are sized to receive the two shafts which are to be connected. A pair of nuts, each having a threaded tapered bore extending therethrough are threaded over the outer tapered surfaces of the two hubs until the nuts exert an inner radial force on the hubs, thereby causing the hubs to frictionally grip and hold the shafts against movement relative to the coupling body. The coupling body may be longitudinally divided into two separate halves which embrace the opposite sides of the shafts and which are held together by the nuts which surround the tapered hub portions thereof.

Abstract: Two support assemblies for respectively supporting the tapered end and the cylindrical end of an elongated tubular elastomeric spring between two opposed spring seats are disclosed. The support assembly for the tapered end is made up of an elongated retaining member which is positionable generally transverse to and entirely inside the tapered end. This retaining member includes two inclined portions which bear down upon the inside of the tapered end when pulled in an outward direction by a bolt thredably secured to a convetional spring seat. The support assembly for the cylindrical end is made up of a second retaining member which is positionable generally transverse to and entirely inside the cylindrical end. The second retaining member includes a plurality of expandable flange portions which engage the inside of the cylindrical portion as the retaining member is pulled in an outward direction by a second bolt threadably secured to the second spring seat.

Abstract: Two support assemblies for respectively supporting the tapered end and the cylindrical end of an elongated tubular elastomeric spring between two opposed spring seats are disclosed. The support assembly for the tapered end is made up of an elongated retaining member which is positionable generally transverse to and entirely inside the tapered end. This retaining member includes two inclined portions which bear down upon the inside of the tapered end when pulled in an outward direction by a bolt threadably secured to a conventional spring seat. The support assembly for the cylindrical end is made up of a second retaining member which is positionable generally transverse to and entirely inside the cylindrical end. The second retaining member includes a plurality of expandable flange portions which engage the inside of the cylindrical portion as the retaining member is pulled in an outward direction by a bolt threadably secured to the second spring seat.

Abstract: In a linked bar member-type apron arrangement for protecting guide tracks, drive assemblies, positions which are liable to accident, or the like, in machine tools or the like, the bar or plate members are each connected together by individual bendable elements which are each secured to the two adjoining plate or bar members. The fixing is preferably made by form-lockingly connecting the bar members to the bendable elements. The bar members preferably comprise extruded aluminium members and the bendable elements preferably comprise extruded polyurethane members. The apron arrangement is easy and inexpensive to produce, extremely durable, easy to handle and highly bendable.

Abstract: The use of a bifurcated joint to attach a conveniently sized metal flange to a flexible bellows material has been widely used, for example, in the manufacture of a building construction expansion joint cover. The known bifurcated joint is formed by clamping and engaging a marginal edge of the bellows material between opposed folded portions of the metal flashing. It has been found that the attaching force provided by this joint can be enhanced by providing teeth or protrusions in a portion of the metal bifurcated joint. Preferably a punch is used to upset teeth from one surface of the joint, preferably a corrugated portion of the joint, and then bend the thus toothed and corrugated portion into clamping engagement with the marginal edge of the bellows. The toothed hole clampingly engages the bellows material without piercing it and prevents pull out, both prior to curing of the adhesive bond as well as thereafter.

Abstract: A universal joint coupling including four identical cast parts, two of the four parts located on either side of disc of flexible material, each of the two parts conformed so as to fit together to form a shaft holding element having strength comparable to that of a single machined part.

Abstract: An elastic axial-rotation coupler has two inelastic devices for respective, inelastic connection to the two axially-rotatable structures, one of the devices defining an annular chamber therein. The annular chamber may be open radially inwardly, but is closed axially and radially outwardly by the inelastic device defining it. At least one resilient element is in the annular chamber and connected to each device for rotatably coupling them resiliently and, thereby, so coupling the axially-rotatable structures which can be connected to the devices. The resilient element preferably is a rubber-elastic body. At least when the structures axially rotate the devices, a liquid is also in the annular chamber for impinging on the resilient element where the centrifugal force of its rotation with the devices would distort it. The liquid preferably has substantially the same density as the resilient element.

Abstract: A flexible structural joint of "flex joint" for use in an articulated structure is disclosed. The articulated structure has a first section and a second section which are located along a longitudinal axis of the structure, the first section being subject to lateral or transverse loads. The flex joint is located between the first and second sections and accommodates lateral pivoting of the first section with respect to the second section through elastic flexing or bending of certain of its members. No moving parts are used. In a first embodiment, the flex joint consists of an elongated axial load member and at least three shear and torsion links oriented so as to lie substantially in a plane perpendicular to the longitudinal axis of the structure. Each of the links is connected at one of its ends to the first section and at its other end to the second section.

Abstract: A highly-resilient shaft coupling includes a hub for rotating about a longitudinal axis, a drive ring, a resilient ring assembly including two axially-continuous circular ring parts bearing radially on the hub. Each ring part includes elastomeric ring sectors and ring sector plates adhered to opposite axial ends of each elastomeric ring sector. An elastomeric ring sector of one circular ring part spans parts of two elastomeric ring sectors of the other ring part. A drive ring drivingly interconnects the hub and the resilient ring assembly at one axial end thereof. Fastener means secure together the ring sector plates at one axial end of each of the two circular ring parts, in a confronting relation. Passageways for cooling air extend between the ring sectors which are secure together. A coupling part is secured to one of the ring sectors at the end which is opposite the drive ring.

Abstract: Brace for use on a body limb having a joint, wherein a cuff is adapted to be attached to the limb above the joint and a cuff to be attached to the limb below the joint, the two cuffs being joined by a connecting member. The connecting member consists of a main body having a track in which lies a limiting element, the limiting element allowing the main body to be bent one direction only, but not in any other.

Abstract: This invention relates to a tool with at least one wear-resistant hard metal part which serves to process production pieces, stones, or the like, wherein the hard metal part is firmly connected with a metallic carrier by solder located in at least one solder aperture. In order to reduce the danger of formation of tension cracks in the hard metal part, the invention provides that at least one predetermined weak point is created in the solder aperture.