The present invention relates to contactors for unidirectional DC operation with permanent magnetic arc extinguishing. In addition to the blow magnets, the contactors are equipped with compensatory permanent magnets for compensating the magnetic field in the vicinity of the contact bridge in order to prevent contact levitation, i.e., an uncontrolled opening of the contacts that is due to a magnetic force generated by a strong current flowing through the contact bridge. To this end, the compensatory permanent magnets are arranged in the vicinity of the contact bridge and polarized in the opposite direction of the blow magnets. The magnetic field of the compensatory magnets and the current flowing through the contact bridge are generating a magnetic force that acts on the contact bridge and tends to keep the electrical contacts closed.

An arc runner assembly for use in a circuit interrupter provides a pair of arc runners that are situated at opposite sides of a stationary contact of the circuit interrupter. If used in a DC application, the arc runner assembly is configured to communicate a positive DC arc along one of the arc runners in a first direction away from the stationary contact and is further configured to communicate a negative DC arc along the other arc runner in another direction away from the stationary contact. The arc runner assembly additionally includes a support that is electrically engaged with a conductor of the circuit interrupter on a surface opposite that on which the stationary contact is disposed. The improved arc runner assembly advantageously facilitates extinction of electrical arc and extinguishes both positive and negative DC arcs in a DC application.

A circuit protection device is provided for use with a circuit that includes at least one pair of conductors. The protection device is configured to generate an arc. The protection device includes at least a pair of electrode assemblies electrically coupled to the at least one pair of conductors and a conductor base to support the pair of electrode assemblies. The protection device includes a cover coupled to the conductor base and defining at least one isolation chamber, wherein the electrode assemblies are disposed within the isolation chamber. The protection device includes a containment shield moveably coupled to the cover. The containment shield defines a containment chamber configured to contain charged particles produced by the arc. The containment shield is operative to move relative to the cover in response to a change in pressure produced by the arc within the containment chamber. An isolation assembly is coupled to at least one of the cover and the containment shield and configured to prevent the cover from contacting the containment shield.

Equipment protection systems, arc containment devices, and methods of assembling arc containment devices are disclosed. In one example, an electrical isolation structure includes a conductor base, a cover coupled to the conductor base and defining an isolation chamber, a containment shield disposed on the conductor base within the isolation chamber, and a biasing assembly positioned between the cover and the containment shield. The containment shield defines a containment chamber configured to enclose the plurality of electrode assemblies. The containment shield is configured to at least partially contain the arc products within the containment chamber. The biasing assembly is configured to permit the containment shield to move away from the conductor base to thereby define a gap between the conductor base and the containment shield to enable at least some of the arc gases to vent from the containment chamber.

A flexible shunt for a vacuum circuit breaker can have a reduced straight length and improved flexibility even with an increased thickness within a predetermined accommodation space of a main circuit part. The flexible shunt comprises a pair of conductive plates, each including a clamp connecting portion configured as a flat conductive member, the clamp connecting portion being connected the clamp, a terminal side connecting portion configured as a flat conductive member, the terminal side connecting portion being connected to the terminal side, and a flexible curved portion configured to connect the clamp connecting portion to the terminal side connecting portion, the flexible curved portion being formed to be projected outwardly.

A circuit breaker includes a first contact and a second contact. An electric arc zone is disposed between the contacts. A feed channel opens into the electric arc zone, connecting the electric arc zone to a hot gas reservoir volume. The hot gas reservoir volume, in turn, is connected to a compression volume. An outflow opening is disposed in a wall of the compression volume. The outflow opening is permanently open, at least in a contacting state of the contacts.

Circuit breakers include an arc chamber and an arc chute comprising a plurality of arc plates in the arc chamber. The circuit breakers also include a line conductor assembly with at least one arc runner attached to a line conductor in the arc chamber. The arc runner can extend below but adjacent to a bottom arc plate to thereby guide a respective arc into the arc chute.

A gas-insulated circuit interrupter is disclosed, the interrupter having an improved design for quenching electrical arcs. The interrupter includes a first contact and a second contact configured to alternatively connect to and disconnect from the first contact. One or both of the contacts are at least partially contained in an arcing chamber. The arcing chamber includes the point at which the contacts connect during current-carrying operation of the interrupter. The arcing chamber is at least partially surrounded by a heating chamber for accommodating a quenching gas. A channel connects the heating chamber and the arcing chamber and is positioned to direct the quenching gas toward the first contact and the second contact arcing area. One or more valves direct gas from the arcing chamber to the heating chamber when the interrupter is operated to interrupt a current.

An electrode assembly for a vacuum interrupter is configured such that supporting members can support most of a contact electrode plate and a supporting electrode plate in an axial direction with coil conductors interposed therebetween. Accordingly, an impact generated between electrode assemblies upon a closing operation of the vacuum interrupter may be evenly distributed onto the supporting members, which may result in preventing each of the electrode plates and the coil conductors from being deformed. Also, the supporting members are inserted into the electrode plates and the coil conductors, thereby effectively preventing a current from flowing via the supporting members. In addition, the supporting member may be wide and large so as to simplify an assembly operation and reduce an assembly time.

A removable faceplate for a portable electronic device is provided. The faceplate permits a user to change the physical appearance of a surface of the device while retaining access to the mechanisms for controlling the function of the device. Preferably, the removable faceplate and electronic device are configured with a means for association and dissociation that can be activated without the use of a tool and the means is not visible when the faceplate is attached. Additionally, an improved packaging system is provided to enable a vendor or manufacturer to package faceplates with the devices that they will cover and to allow substitution of faceplates in the packaging without disturbing the packaging of the electronic device itself. Further, there is a method for distribution of the packaging system.

Containers and dispensers for wiping substrates, and wet wiping substrates in particular, have been provided with lids, the containers have been susceptible to leakage, or difficulties in dispensing the contents. Provided is a refillable container for storing and dispensing wiping substrates. A refill cartridge containing wiping substrates having a peelable seal disposed on a first surface and a second surface for forming a seal with the container lid is provided.

A packaging device includes first and second thermoplastic films superposed with each other, wherein predetermined portions of the thermoplastic films are bonded creating a plurality of fluid containers, a plurality of check valves each connected to a corresponding fluid container, a fluid passage in a first direction connected to the check valves, and a second border between an inflated section including the plurality of fluid containers and an uninflated section, wherein the first and second thermoplastic films are folded and two side edges of the films are bonded and a first portion of a first border connecting the inflated section to a second section is folded and an overlapped portion of the first portion is bonded leaving a remaining portion of the first border unbonded wherein the uninflated section forms a loop, and wherein the uninflated section forming the loop is folded into the inflated section to form a lining.

Container assemblies can include a first container and a second container, where the second container extends into and is supported by the first container. The first container and the second container can each include a flange around the periphery of an access opening. The flange of the second container is configured to provide support for the second container via engagement with the flange of the first container. In some instances, the second container can extend into and be supported by the first container through engagement of the flange of the second container with the flange of the first container such that a side panel of the first container is not in contact with a corresponding side panel of the second container. The container assembly can also include a lid for retaining the second container in the first container and/or for sealing to the first container and/or the second container.

The present invention provides an assembly for the preparation of a medical device having a porous coating comprising hydrogen peroxide. Particularly interesting medical devices are catheters (such as urinary catheters), endoscopes, laryngoscopes, tubes for feeding, tubes for drainage, guide wires, condoms, urisheaths, barrier coatings e.g. for gloves, stents and other implants, extra corporeal blood conduits, membranes e.g. for dialysis, blood filters, devices for circulatory assistance, dressings for wound care, and ostomy bags. The coating is in particular a hydrophilic coating formed from cross-linked polyvinylpyrrolidone. In one embodiment, the assembly holds a dry catheter element in one compartment of a package and an aqueous hydrogen peroxide solution in another compartment. The solution may also comprise stabilizers, e.g. chelators, and osmolality increasing agents. The catheter for insertion in the urethra is useful for the treatment, alleviation or prophylaxis of microbial infections such as urinary tract infections (UTI).

A housing shell for electrical measuring, controlling and communication devices, in particular the lower housing part of a cellphone, has very great flexural and torsional rigidity in spite of an extremely small wall thickness if it is formed as a part created by a forming operation from the planar blank of a thermoplastically impregnated long-fibered multi-layered mat. Fine-membered functional elements of likewise thermoplastic material are then molded onto the housing shell in an injection mold.

A novel packaging for flat media having substantially square panels wherein at least one of the panels is adapted to form a compartment for storing a phonographic record, an audiovisual record or any flat media. The arrangement of the square panels enables the package to be folded in a compact, flat configuration for ease of storage and shipping. When erected, the package forms a cube that could be used as additional storage. The cube may be erected with either of the sides of the panels visible so as to afford greater opportunity for display.

A holder is for supporting a portable electronic device, including at least one sheet. A base portion, a first supporting portion and a second supporting portion formed on the at least one sheet. The base portion, the first supporting portion and the second supporting portion are parallel with each other and folded relative to each other. A latching piece is formed on the base portion, the latching piece having a bendable portion. The first supporting portion is folded relative to the base portion, and the second supporting portion is folded relative to the first supporting portion until the second supporting portion is held by the latching piece, the base portion, the first supporting portion and the second supporting portion cooperatively form a three-dimensional structure that can support the portable electronic device at an angle relative to the at least one sheet without collapsing.

A catheter assembly including an elongate member having a proximal end and a distal end. The distal end has at least one drainage opening. A hydrophilic coating is provided on at least a portion of the elongate end of the catheter. A fluid containing member is provided and is either arranged on the elongate member or within a separate area of the container. The fluid containing member contains sufficient hydrating fluid to hydrate the coating of the catheter. A container contains the elongate member and the fluid containing member and incorporates at least one foil layer to prevent evaporation of the hydrating fluid. A method of using the catheter includes inserting a catheter into a user's body and draining fluid from the user's body.

A sterilizable pouch for surgical instruments includes a sterilant permeable sheet with a first sealing strip and a sterilant impermeable sheet with a second sealing strip. The sealing strips are sealed together to define the pouch. At least one sealable open portion is for sealing the pouch after surgical instruments are located inside the pouch. An indicator material for indicating sterile processing conditions inside the pouch is located on an inner surface of the sterilant impermeable sheet inside the pouch.

A toilet tissue roll holder is provided having a telescoping structure that is attachable to a wall surface for providing replacement toilet tissue to a dispenser and shrouding unused rolls prior to deployment. The device includes a lowermost housing having a base surface, rounded sidewalls, an interior volume, and an open front. The lowermost housing connects to a first upstanding sidewall thereabove, which in turn supports a plurality of telescoping sidewalls that form individual toilet tissue roll containers extending upward. A viewing window is provided through at least one of the device sidewalls above the lowermost housing to allow an administrator to visualize whether a minimum number of reserve toilet paper rolls are still available. The structure is expanded and contracted depending on the number of rolls therein, while the lowermost housing and first upstanding sidewall provide the base structure that is secured to a support wall.

A reversible folio for a tablet computer has a tablet shell with a cavity removably receiving the tablet computer. A keyboard is pivotally and removably coupled to the tablet shell. A channel is pivotally coupled to an edge of the keyboard. An interior of the channel removably receives the proximal edge of the tablet shell, and has a profile mating with a profile of the tablet shell. The channel and proximal edge have first and second symmetrical magnet arrays, respectively. The proximal edge of the tablet shell physically mates with the channel of the keyboard, and the second magnet array of the tablet shell magnetically mates with the first magnet array of the channel, in both a first orientation and an opposite second orientation.

A container has a base and walls connected to the base to define an interior space. The walls have upper edges that terminate in a plane and define an opening for access to the interior space. Wetted donnable articles are stacked within the container, each article in a flat configuration at least partially perpendicular to the opening permitting withdrawal of any one of the donnable articles through the opening in a flat configuration. Walls on opposing sides of the base of the container diverge from each other with increasing distance from the base, such that the interior space widens gradually toward the opening. Walls on other opposing sides of the base have lower portions connected to the base and upper portions connected to the lower portions by steps that lengthen the interior space abruptly.

A golf caddie device is disclosed that is designed for carrying golf equipment. The golf caddie device comprises a support rod having a spike and an ergonomically shaped handle. The golf caddie device also comprises a ball holder, a first cylinder comprising up to five openings for retaining golf clubs, and a second cylinder comprising up to five openings for retaining golf club shafts. Golf clubs are inserted into the golf caddie device by inserting the shaft part of the golf club through one of the first cylinder openings and into one of the openings of the second cylinder, thus, retaining the golf clubs within the golf caddie device.

A package for a medical device having an elongated shaft and a proximal luer fitting includes a one-piece body formed as a single structure via blow molding. The blow-molded one-piece body includes at least a spiral casing formed therein, the spiral casing defining a spiral lumen configured to receive the elongated shaft of the medical device. Webbing is disposed between adjacent curved portions of the spiral casing. The one-piece body formed via blow-molding may also include a removable reversible loading tube, a luer retainer, a cannula holder, one or more slots for attaching an information card thereto, a fastener for clipping the medical device thereto, and a compartment for holding an oxygen scavenger. Further, the one-piece body formed via blow-molding may include non-circular lumens and may be configured to receive multiple medical devices.

A stackable cup having a rigid handle with an open top, the open top shaped and dimensioned to receive a complementary handle of a stackable cup of the like such that one or more cups may be angularly stacked, the cup having a lip projecting from the open top and extending outwardly to a circular rim, which in turn extends downwardly to define the drinking cup.

A packaging box with test strips is provided for a gripper to grip the test strips, and the gripper has a gripping section and a conductive terminal in the gripping section, and the packaging box includes a main body and a test strip. The main body has an embedded groove including a port with a shape corresponding to the shape of the gripping section, and the port is provided for inserting the gripping section. The test strip has a conductive area defined on a surface of the test strip, and the test strip is contained in the embedded groove, wherein the gripping section is coupled to the port, and the conductive terminal is electrically coupled to the conductive area. With the packaging box, the test strips can be taken out conveniently and quickly.

A multifunctional case is configured for receiving or supporting a portable electronic device. The case includes a first layer and a second layer. The second layer is connected to the first layer by the edges. A receiving space is formed between the first and second layers for receiving the portable electronic device. The second layer is provided with a base portion, a main supporting portion, two side supporting portions and two remaining portions are formed on the second layer. The two side supporting portions and the remaining portions are symmetrically positioned at two sides of the main supporting portion. When the case is folded up as a support, the main supporting portion is angled with the base portion. The remaining portions are stacked on the base portion. The side supporting portions are perpendicular to the remaining portions and the main supporting portion.

An ultra removable booklet with label for application to media is described. The booklet with label includes a release liner, an ultra removable adhesive layer, a paper stock layer, a booklet, an adhesive layer, and a clear plastic cover layer. The clear plastic cover layer has the adhesive layer applied to a bottom surface thereof and the bottom surface is positioned over the booklet. The booklet is positioned over the paper stock. The ultra removable adhesive layer is attached to the lower surface of the paper stock. The release liner is applied to the ultra removable adhesive layer. A process for forming an ultra removable booklet with label for application to media is also described.

Embodiments of the invention are directed to reusable notecard. In one embodiment, the reusable notecard is comprised of a trifold panel having a left panel, a center panel and a right panel and a reclosable closing mechanism, connected to the trifold panel, to releasably secure the left panel to the right panel when folded over one another. In one embodiment, the adjustable left panel is comprised of a plurality of left panel fold lines and the right panel is comprised of a plurality of right panel fold lines, the plurality of left panel fold lines and the plurality of right panel fold lines for adapting to dimensions of contents inside the notecard. In one embodiment, the trifold panel is made of a material allowing for non-permanent markings.

An apparatus (10) for transporting items includes a base (12), a handle element (16) extending from the base (12), a pair of rollers or wheels (20) mounted to the base (12) and a platform (14) mounted to the base (12) and adapted for movement between a stored condition and an operative position. The platform (14) includes first and second leg elements (24) and a platform support (26) connected to the first and second leg elements (24) and extending therebetween. The platform (14) is dimensioned and adapted to carry an object when in the operative position. The platform support (26) may comprise a flexible material such as a fabric material.

An integrable bookstand adapted to be integrated into a hard back cover of a book is disclosed. The integrable bookstand having a withheld and deployed conformations. In the withheld conformation the bookstand is coplanar with the hard back cover, rendering the latter storable in tandem between other flat articles.

A communications device may include a near-field communication (NFC) circuit device, and a radio frequency (RF) signal blocking member adhesively coupled with the NFC device. The RF signal blocking member may be configured to block RF signal communication by the NFC device while coupled therewith. The RF signal blocking member may comprise an electrical conductor. In accordance with an example, the RF signal blocking member may comprise a frangible layer. In another example, a pressure sensitive adhesive layer may be included for adhesively securing the RF signal blocking member with the NFC device.

A binder management system having a cabinet with shelves for removable storage of searchable binders. Each binder has a body with front and rear covers and a spine. Inside the body is a binder mechanism for removably retaining sheet media. Each binder has externally extending upper and tower ohmic contact members which ohmically engage conductive members mounted on the shelf surfaces near the front. Each binder has a binder identification circuit coupled to an LED mounted on the binder spine in a location visible when the binder rests on a shelf. When a binder identification signal from a host computer is presented to the shelf conductive members it is transferred by the binder contact members to the binder identification circuit. If the signal matches, the LED is activated to aid the user in finding the binder. An LED and an optional audible indicator are mounted on the shelves to further aid the user in finding the sought binder.

A clipboard for keeping lists of items for purchases is described. The clipboard includes a dry-erase board, a paper pad, a holder for a dry-erase marker, a holder for an ink pen, a plurality of magnets for holding the clipboard to a ferro-magnetic surface, and a folding board having a clip for attaching to the clipboard to a shopping cart handled. The clip is configured to enable tilting the clipboard with mounted on a shopping cart handle. The clipboard can be moved from a refrigerator, carried to a store, and then clipped onto a shopping cart.

Disclosed is a plastic film with concealed tearable strip, which includes a film body; at least one first tearable strip having two sides respectively forming first and second joint sections; and at least one second tearable strip having two sides respectively forming a third joint section and an internal tear line. The first and second tearable strips each have one side connected to the film body. The first joint section has two sides each forming a tear line. The third joint section has one side forming at least one tear line. The third joint section and the internal tear line have inside faces respectively coupled to the first and second joint sections, whereby the first and second tearable strips are respectively located at outside and inside of the film body and the second tearable strip is concealed at the inside of the film body.

A highlighter strip including adhesive to form a removable bond with a substrate, constructed from a translucent and colored material. The highlighter strip can be affixed over writing or other markings, which highlights the indicia that remains legible. One or both ends of the strip can omit the adhesive, thereby providing a grabbing portion to facilitate removal from an initial position and optionally subsequent positions. The strip can be included in a set of strips affixed to each other and optionally affixed to another base; such as a notebook, binder, or other entity where one would expect writing, text, or other indicia requiring highlighting.

A book binding structure which includes at least one adhesive binder strip and a pair of supporting sheets for supporting the binder strip during a binder strip printing process. Opposite ends of the binder strip are supported on separate support sheets, which are coupled together only by way of the binder strip to allow independent movement of the ends of the binder strip. The sheets are arranged to support the binder strip as is passes along the paper path of a conventional printer.

A foldable and unfoldable pop-up article with a tensioning member.

A publication including a plurality of pairs of pages, with the pair of pages comprised of a removable page and non-removable page. The removable page has a perforated edge, an adhesive edge opposite the perforated edge and a printable surface. The non-removable page has a printable surface. The pairs of pages are arranged such that alternate pages are removable and can be removed without harming the publication or the non-removable pages. The removable pages can be arranged to form an image larger than the publication itself and removable attached to a surface through the adhesive edge.

A variable gain amplifier (100) includes a transistor (110), an FB impedance section (120), a source impedance section (130), a drain impedance section (140), a gain controller (150), and a frequency characteristic controller (160). The gain controller (150) varies impedance of one of the FB impedance section (140), the source impedance section (130), and the drain impedance section (140), and outputs a gain control signal. The frequency characteristic controller (160) varies the impedance of different impedance section, based on the gain control signal.

A tunable wide band driver amplifier is disclosed. In an exemplary embodiment, an apparatus includes a first band selection circuit selectively connected between an output terminal of an amplifier and a circuit ground. The first band selection circuit configured to adjust an amplification band from a first frequency band to a second frequency band. The apparatus also includes a first harmonic reduction circuit selectively connected between the first band selection circuit and the circuit ground and configured to reduce 2nd harmonic frequencies associated with the first frequency band when the amplification band is set to the first frequency band.

An amplifier circuit amplifies a signal for wireless transmission. A feedback circuit, including a capacitor, is coupled to the amplifier circuit. Components of the feedback circuit are selected based on a feedback factor such that an input impedance to the amplifier circuit has a same impedance characteristic as a feedback circuit impedance of the feedback circuit.

Apparatus and methods disclosed herein perform gain, clipping, and phase compensation in the presence of I/Q mismatch in quadrature RF receivers. Gain and phase mismatch are exacerbated by differences in clipping between I & Q signals in low resolution ADCs. Signals in the stronger channel arm are clipped differentially more than weaker signals in the other channel arm. Embodiments herein perform clipping operations during iterations of gain mismatch calculations in order to balance clipping between the I and Q channel arms. Gain compensation coefficients are iteratively converged, clipping levels are established, and data flowing through the network is gain and clipping compensated. A compensation phase angle and phase compensation coefficients are then determined from gain and clipping compensated sample data. The resulting phase compensation coefficients are applied to the gain and clipping corrected receiver data to yield a gain, clipping, and phase compensated data stream.

A voltage converter can be switched among two or more modes to produce an output voltage tracking a reference voltage that can be of an intermediate level between discrete levels corresponding to the modes. One or more voltages generated from a power supply voltage, such as a battery voltage, can be compared with the reference voltage to determine whether to adjust the mode. The reference voltage can be independent of the power supply voltage.

A machining system that includes an ultrasonic machining assembly, wherein the ultrasonic machining assembly further includes a machining tool; a collet adapted to receive the machining tool; and an ultrasonic transducer, wherein the ultrasonic transducer is operative to transmit acoustical vibrations to the machining tool; and a machining apparatus, wherein the machining apparatus is adapted to receive and secure the ultrasonic machining assembly, and wherein the machining apparatus is operative to transmit torque to the machining tool by applying rotary motion to the ultrasonic machining assembly.

An attachment apparatus for a reciprocating tool provides a tool holder having an angled bracket and a guide rod extending from the angled bracket. The guide rod can engage a travel slot on the reciprocating tool. An instrument such as a saw blade can be attached to the angled bracket or guide rod. The guide rod stabilizes the instrument during use. The travel slot can be defined integrally on the reciprocating tool or on an attachment to the tool. In some embodiments, a neck mount assembly is attached to the neck on the reciprocating tool. The neck mount assembly can include a frame and a guide plate. The guide plate can include a travel slot shaped for receiving the guide rod.

A thermally zoned substrate holder including a substantially cylindrical base having top and bottom surfaces configured to support a substrate. A plurality of temperature control elements are disposed within the base. An insulator thermally separates the temperature control elements. The insulator is made from an insulting material having a lower coefficient of thermal conductivity than the base (e.g., a gas- or vacuum-filled chamber).

A workholder to hold a workpiece, including a main body partially defining a fluid chamber, and a bladder carried by the main body with an interference fit, further defining the fluid chamber, and composed of an 80 to 100 durometer Shore A scale hardness polymer of a 12:1 to 18:1 diameter-to-wall-thickness ratio. Annular seals may further define the fluid chamber, and are disposed radially between the bladder and main body and axially adjacent the fluid chamber, and are composed of a 60 to 80 durometer Shore A scale hardness polymer. A collet is carried and driven by the bladder for gripping engagement with the workpiece.

A pin-and-collet assembly, a longwall shearer comprising a ranging arm attached to a lifting bracket with such assembly, a method for the secure fastening of one piece to another, such as securely fastening the ranging arm to the lifting bracket of a longwall shearer using such assembly as a bushing, and a method for longwall mining of ore, such as trona, using such longwall shearer. This assembly is easy to install, does not have to be tightened during longwall operation of an ore panel, and is also demountable when it is time to stop the longwall mining operation and time to remove/replace the ranging arm for maintenance and/or when the end of the ore panel is reached.

The present invention relates to a hole-saw assembly (10) including a hole saw (26) having at one end a plurality of cutting teeth and at the other end two shafts. The assembly includes a mandrel (16) coaxially aligned with said hole-saw and including a body having two bores there through coaxially aligned with said shafts. An annulus (20) located on top of the body is coaxially aligned with said mandrel and hole saw and includes two holes, the annulus rotatable around its longitudinal axis from a first to a second position. In the first position the annulus holes are aligned with the bores and shafts allowing the shafts to be freely insertable and removable and in the second position the holes are misaligned to lock the shafts to the annulus. The mandrel further includes a pair of driving pins (22) adapted to engage driving apertures (24) found in hole saws especially larger ones. Typically the driving pins may biased to enable the assembly to be used even with those hole saws that do not include driving apertures and that also enables easier assembly of the device. A compressible O-ring (42) may further facilitate the operation of the assembly. This device avoids the problem of thread stripping.