Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B47/00—Drives or gearings; Equipment therefor
  • B24B47/10—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces
  • B24B47/14—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces by liquid or gas pressure
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25C—HAND-HELD NAILING OR STAPLING TOOLS; MANUALLY OPERATED PORTABLE STAPLING TOOLS
  • B25C1/00—Hand-held nailing tools; Nail feeding devices
  • B25C1/08—Hand-held nailing tools; Nail feeding devices operated by combustion pressure
  • B25C1/10—Hand-held nailing tools; Nail feeding devices operated by combustion pressure generated by detonation of a cartridge
  • B25C1/14—Hand-held nailing tools; Nail feeding devices operated by combustion pressure generated by detonation of a cartridge acting on an intermediate plunger or anvil
  • B25C1/143—Hand-held nailing tools; Nail feeding devices operated by combustion pressure generated by detonation of a cartridge acting on an intermediate plunger or anvil trigger operated
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
  • B23D15/00—Shearing machines or shearing devices cutting by blades which move parallel to themselves
  • B23D15/12—Shearing machines or shearing devices cutting by blades which move parallel to themselves characterised by drives or gearings therefor
  • B23D15/14—Shearing machines or shearing devices cutting by blades which move parallel to themselves characterised by drives or gearings therefor actuated by fluid or gas pressure
  • B23D15/145—Shearing machines or shearing devices cutting by blades which move parallel to themselves characterised by drives or gearings therefor actuated by fluid or gas pressure actuated by explosion
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25F—COMBINATION OR MULTI-PURPOSE TOOLS NOT OTHERWISE PROVIDED FOR; DETAILS OR COMPONENTS OF PORTABLE POWER-DRIVEN TOOLS NOT PARTICULARLY RELATED TO THE OPERATIONS PERFORMED AND NOT OTHERWISE PROVIDED FOR
  • B25F5/00—Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
  • F42B5/00—Cartridge ammunition, e.g. separately-loaded propellant charges
  • F42B5/02—Cartridges, i.e. cases with charge and missile
  • F42B5/03—Cartridges, i.e. cases with charge and missile containing more than one missile
  • F42B5/035—Cartridges, i.e. cases with charge and missile containing more than one missile the cartridge or barrel assembly having a plurality of axially stacked projectiles each having a separate propellant charge

Definitions

• This invention relates to a power source for providing energy to drive various mechanical devices such as power tools.
• This invention also relates to power tools and to a method of providing energy to drive power tools.
• the present invention at least in so far as it relates to a power source, will be described hereunder for use in providing energy to drive power tools although it will be understood that the power source may be used to provide energy to other mechanical devices.
• Power tools may be driven by a variety of power sources. For example continuous power may be provided by electricity and air driven motors. Electric and air powered motors need to be connected to an electricity or air supply respectively. Whilst batteries and compressed air packs may provide a portable power supply, generally such portable power supplies cannot provide the power necessary for applications requiring large amounts of energy to be delivered over a short period of time. These motors, as well as linear actuators, may be utilised to drive power tools requiring intermittent power such as nail guns, power chisels and the like. Some nails guns have also been powered by explosive cartridges. However the use of explosive cartridges are not particularly suited where prolonged repetitious use is required as frequent reloading of the cartridges is required.
• a power source for providing energy to drive a mechanical device including a receiving chamber and discrete propellant charges for selective detonation whereby gases generated by the selective detonation expand into the receiving chamber wherein said receiving chamber includes a reactive closure which dynamically responds to pressure changes in the receiving chamber and wherein said power source further includes a linkage associated with the reactive closure for transmitting energy from the dynamic response of the reactive closure to the mechanical device.
• the power source includes a receiving chamber into which the gases generated by the detonation of the propellant may expand. The receiving chamber accommodates the expanded gases and will withstand the pressures generated.
• the receiving chamber may be constructed out of any suitable material that can retain the expanded gases without substantial deformation in order that the energy released by the detonation of the propellant is transferred to the reactive closure.
• the receiving chamber may be constructed from cast metals including aluminium and steel or from reinforced plastics materials.
• the discrete propellant charges may preferably be contained in one ore more cartridges of the type described in International Patent Application Nos. PCT/AU94/00124 and PCT/AU96/00459.
• Such cartridges includes a shell; a plurality of separator projectiles axially disposed within the shell for operative sealing engagement with the bore of the tubular shell, and discrete propellant charges.
• the projectile separator may be of any convenient shape to provide sealing engagement with the bore of the shell and permit the selective detonation of the propellant charges.
• the propellant charge may be form as a solid block or the propellant charge may be encased in metal or other rigid case which may include an embedded primer having external contact means adapted for contacting an pre-positioned electrical contact associated with the case.
• the primer could be provided with a sprung contact which may be retracted to enable insertion of the cased charge into the shell and to spring out into an aperture upon alignment with that aperture for operative contact with its mating shell contact.
• the case may be consumable or may chemically assist the propellant burn.
• Each projectile separator may include a head and extension means for at least partly defining a propellant space.
• the extension means may include a spacer assembly that extends rearwardly from the projectile head and abuts an adjacent projectile assembly.
• the spacer assembly may extend through the propellant space and the projectile head whereby compressive loads are transmitted directly through abutting adjacent spacer assemblies.
• the spacer assembly may add support to the extension means that may be a thin cylindrical rear portion of the projectile head.
• the extension means may form an operative sealing contact with the bore of the shell to prevent burn leakage past the projectile head.
• the spacer assembly may include a rigid collar which extends outwardly to engage a thin cylindrical rear portion of the malleable projectile head inoperative sealing contact with the bore of the shell such that axially compressive loads are transmitted directly between spacer assemblies thereby avoiding deformation of the projectile spacer.
• Complementary wedging surfaces may be disposed on the spacer assembly and projectile spacer head respectively whereby the projectile spacer head is urged into engagement with the bore of the shell in response to relative axial compression between the spacer means and the projectile spacer head.
• the projectile spacer head and spacer assembly may be loaded into the barrel and there after an axial displacement is caused to ensure good sealing between the projectile spacer head and barrel.
• the extension means is urged into engagement with the bore of the barrel.
• the projectile head may define a tapered aperture at its rearward end into which is received a complementary tapered spigot disposed on the leading end of the spacer assembly, wherein relative axial movement between the projectile spacer head and the complementary tapered spigot causes a radially expanding force to be applied to the projectile spacer head.
• the shell may be non-metallic and the bore of the shell may include recesses which may fully or partly accommodate the ignition means.
• the shell houses electrical conductors which facilitate electrical communication between the control means and ignition means.
• This configuration may be utilised for disposable shell assemblies which have a limited firing life and the ignition means and control wire or wires therefor can be integrally manufactured with the shell.
• a cartridge may alternatively include ignition apertures in the shell and the ignition means are disposed outside the shell and adjacent the apertures.
• the shell may be surrounded by a non-metallic outer shell which may form the sleeve which may include recesses adapted to accommodate the ignition means.
• the outer shell may also house electrical conductors which facilitate electrical communication between the control means and ignition means.
• the outer shell may be formed as a laminated plastics shell which may include a printed circuit laminate for the ignition means.
• the cartridge may have adjacent propellant charges that are separated from one another and maintained in spaced apart axial relationship by locating means separate from the projectile spacers, and each projectile spacer may include an expandable sealing means for forming an operative seal with the bore of the shell.
• the locating means may be the propellant charge between adjacent projectile spacers and the sealing means suitably includes a skirt portion on each projectile spacer that expands outwardly when subject to an in-shell load.
• the in-shell load may be applied during installation of the projectile spacer or after loading such as by tamping to consolidate the column of projectile spacers and propellant charges or may result from the firing of an outer propellant charge and particularly the adjacent outer propellant charge.
• the rear end of the projectile spacer may include a skirt about an inwardly reducing recess such as a conical recess or a part-spherical recess or the like into which the propellant charge portion extends and about which rearward movement of the projectile spacer will result in radial expansion of the projectile skirt.
• This rearward movement may occur by way of compression resulting from a rearward wedging movement of the projectile spacer along the leading portion of the propellant charge it may occur as a result of metal flow from the relatively massive leading part of the projectile spacer to its less massive skirt portion.
• the projectile spacer may be provided with a rearwardly divergent peripheral sealing flange or collar which is deflected outwardly into sealing engagement with the bore upon rearward movement of the projectile spacer.
• the sealing may be effected by inserting the projectile spacer into a heated shell which shrinks onto respective sealing portions of the projectile spacers.
• the projectile spacer may comprise a relatively hard mandrel portion located by the propellant charge and which cooperates with a deformable annular portion may be moulded about the mandrel to form a unitary projectile spacer which relies on metal flow between the nose of the projectile spacer and its tail for outward expansion about the mandrel portion into sealing engagement with the bore of the shell.
• the projectile spacer may include a rearwardly expanding anvil surface supporting a sealing collar thereabout and adapted to be radially expanded into sealing engagement with the shell bore upon forward movement of the projectile spacer through the shell.
• the propellant charge may have a cylindrical leading portion which abuts the flat end face of the projectile spacer.
• the electrical ignition for sequentially igniting the propellant charges of a barrel assembly may preferably include the steps of igniting the leading propellant charge by sending an ignition signal through the stacked projectiles, and causing ignition of the leading propellant charge to arm the next propellant charge for actuation by the next ignition signal.
• all propellant charges inwardly from the end of a loaded shell are disarmed by the insertion of respective insulating ruses disposed between normally closed electrical contacts.
• Ignition of the propellant may be achieved electrically.
• the ignition is electronically controlled with respective propellant charges being associated with primers which are triggered by distinctive ignition signals.
• the primers in the stacked propellant charges may be sequenced for increasing pulse width ignition requirements whereby electronic controls may selectively send ignition pulses of increasing pulse widths to ignite the propellant charges sequentially in a selected time order.
• the propellant charges are ignited by a set pulse width signal and burning of the leading propellant charge arms the next propellant charge for actuation by the next emitted pulse.
• all propellant charges inwardly from the end of a loaded barrel are disarmed by the insertion of respective insulating fuses disposed between insertion of respective insulating fuses disposed between normally closed electrical contacts, the fuses being set to burn to enable the contacts to close upon transmission of a suitable triggering signal and each insulating fuse being open to a respective leading propellant charge for ignition thereby.
• the propellant charges are selectively detonated to pressurise the receiving chamber.
• one detonation will correspond to one actuation of the mechanical device or power tool, such as for example with a power chisel or the like.
• the actuation of the mechanical device or power tool may rely on the pressure in the receiving chamber being above a preset value and once the pressure drops below a predetermined value a further propellant charge is detonated to maintain the pressure above the preset value.
• the trigger mechanism controls the mechanical device or power tool and the propellant charges are automatically detonated.
• the reactive closure may be a diaphragm or it may be a piston slidably and sealably engaged in the receiving chamber or a portion thereof.
• the diaphragm may be a flat or a bellows type diaphragm which may be resilient so as to return the diaphragm to a datum position after reacting.
• the diaphragm may be biased to the datum position by any suitable means such as by spring or gas chamber biasing.
• the receiving chamber may collect the spent matter such as the separator projectiles or other debris associated with detonation of the explosive/propellant charge or the spent matter may be discharged, suitably through a valve arrangement which remains closed while the expanding explosive/propellant works against the reactive closure.
• the receiving chamber is detachably secured to a cartridge of barrel assemblies.
• the actuating means for selectively firing each or a selected number of projectiles either simultaneously or in series, whereby the operating force of, or duration of operation of the operating member may be selectively varied.
• the actuating means may be associated with the removable cartridge or the receiving chamber.
• the cartridge may be a reloadable cartridge or a one-use throw-away cartridge.
• the linking means may be a plunger which moves with the reactive member.
• the linking means may be a rocker or it may be a fluid pump or other transducer actuated by the reactive member.
• the transducer may also be adapted to transmit a continuous torque to the mechanical device or power tool or a combination of a linear force and torque such as may be employed in a hammer drill or the like.
• a power source which may be employed in a variety of power tools such as hammer chisels, drills, hammer drills, saws, routers, angle grinders, sanders including belt sanders and vibrating sanders, nail guns, horticultural and agricultural machines such as chain saws, shredders, garden edgers, hedge trimmers and other cutting implements, mixing apparatus, planers, concrete hammers, grinders, polishers, nut runners, tappers, hammers, rammers and the like.
• FIG. 1 is a diagrammatic cross-sectional view of a power source for a power tool
• FIG. 2 corresponds to Fig. 1 but illustrates the head portion separated from the cartridge portion
• FIG. 3 is a typical sectional view of a cluster of two barrel assemblies.
• the driver 10 illustrated in Fig. 1 has a receiving expansion chamber 1 1 formed with a bayonet type connection 12 at its trailing end for connection to a cartridge case 13 which contains a cluster of barrel assemblies 14.
• a reactive piston 15 is sealably and slidably supported in the front end portion of the receiving expansion chamber 11. The piston 15 is guided for movement through the receiving expansion chamber 11 by a plunger 16 guided for reciprocal movement in an extension housing 17.
• a biasing spring 18 is supported in the extension housing 17 for biasing the piston 15 to a retracted position as illustrated in Fig. 2. In this position the piston closes exhaust ports 20 provided in the receiving expansion chamber 11.
• a trigger operated actuating handle 21 is shown connected to the cartridge case 13 along with adjustable controls, generally shown at 22, which may be manually set to achieve the desired firing configuration required.
• control may be set to fire a single explosive/propellant charge 23 with each operation of the trigger or it may simultaneously fire a selected number of propellant charges 23 from the leading rounds of charges 23 in the barrels 14.
• control may be set to fire a series of explosive/propellant charges 23 from one or a plurality of barrels and at a rate which provides a prolonged or increased pressurisation of the receiving expansion chamber 1 1. It will be seen that the rear open end of the receiving expansion chamber 1 1 communicates with the open front end 24 of each of the barrel assemblies 14 which fire directly into the receiving chamber towards the piston 15.
• a funnel shaped outlet 25 is provided at the base of the chamber 11 leading to a collection container 26 through a gate valve 27.
• Spent separator projectiles or other debris may pass into the collection container 26 through the gate valve 27 which may be manually controlled or it may be linked to the plunger 16 for automatic opening such as on the return stroke of the plunger 16 as illustrated in Fig. 2.
• each barrel assembly 14 has a plurality of spaced charges 23 separated by a two-part separator projectiles 31 each of which contains a primer 32.
• Each primer 32 makes an electrical connection with a respective control conductor 33 supported in an insulated configuration in the space between adjacent barrel assemblies 14 whereby their ignition may be controlled by electronics in the controls 22.
• Each separator projectile 31 includes a flat nose portion 40 which has a rearwardly diverging conical opening 41 therethrough to receive a complementary tapered leading portion 42 of a trailing part 43 which supports the primer 32.
• the projectiles 31 may be formed from aluminium or other lightweight material including a suitable plastics or ceramic material and as in our previously described International Applications, the projectile relies on a radial expansion of the nose portion 40 through relative axial engagement between the nose portion 40 and the complementary trailing part 43 to effect a sealing engagement with its barrel 29.
• each propellant charge 23 is in the form of a solid block so as to support the a trailing part 43 fixedly in a stacked position in the barrel 14.
• Movement of the plunger 16 is used to actuate the power tool or appliance as required.
• the front end of the driver 10 may be provided with a connector for connecting it to a power tool to provide the necessary drive therefore.
• a support handle 39 is provided. Typically this would be positioned at a point of balance appropriate for the power tool to be used with the driver.
• the charges 23 are relatively large compared to the separating projectiles 31 which in effect operate only as seals between the propellant charges 23.
• the kinetic energy of each projectile 31 upon firing is not utilised in actuating the plunger 16.
• the charges 23 may be varied in size or type depending upon the power characteristics required from the plunger 16.
• the separating projectiles may be retained in position in the barrel by any suitable means such as by being located against internal locating ribs or grooves in the barrel or by circlips or spines extending between the separator projectiles 31.
• each propellant charge 42 is encased in a plastic tube-like casing 43 which has a weakened front wall 44 to permit expanding gas from the propellant detonation to pass forwardly through the barrel 45 and into the receiving expansion chamber 11.
• the limited resilience of the tubular wall 46 of the casing 43 will cause it to expand into tight sealing engagement with the barrel 45 preventing bypass of the gases to the trailing propellant charge in sufficient quantities to cause ignition of that encased trailing charge 23.
• the spent casing 43 will impact and compress against the back face of the piston or other closure of the expansion chamber 1 1.
• the initiation means for detonating the propellant charges 42 may be via an external barrel mounted primer or be achieved electrically through spaced annular contacts extending about the casing 43 and contacting respective sets of contacts in the barrel 45. As illustrated the front wall 44 of the casing 43 is relatively thin so that it will be easily ruptured by detonation of the propellant 42 for propelling the preceding projectile 21 from the barrel.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• General Engineering & Computer Science (AREA)
• Portable Nailing Machines And Staplers (AREA)
• Hydraulic Clutches, Magnetic Clutches, Fluid Clutches, And Fluid Joints (AREA)
• Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
• Devices For Conveying Motion By Means Of Endless Flexible Members (AREA)
• Percussive Tools And Related Accessories (AREA)

Priority Applications (8)

Applications Claiming Priority (2)

Publications (1)

Family

ID=3818344

Family Applications (1)

Country Status (12)

Families Citing this family (7)

Citations (6)

Family Cites Families (16)

• 1999
  • 1999-11-23 AU AUPQ4200A patent/AUPQ420099A0/en not_active Abandoned
• 2000
  • 2000-11-23 CA CA002389625A patent/CA2389625A1/en not_active Abandoned
  • 2000-11-23 JP JP2001539639A patent/JP2003514683A/ja active Pending
  • 2000-11-23 EP EP00977313A patent/EP1232042A4/en not_active Withdrawn
  • 2000-11-23 KR KR1020027006353A patent/KR100739904B1/ko not_active Expired - Fee Related
  • 2000-11-23 WO PCT/AU2000/001425 patent/WO2001038046A1/en not_active Ceased
  • 2000-11-23 IL IL14942800A patent/IL149428A0/xx active IP Right Grant
  • 2000-11-23 CN CNB008160341A patent/CN1153654C/zh not_active Expired - Fee Related
  • 2000-11-23 US US10/130,673 patent/US7117779B1/en not_active Expired - Fee Related
  • 2000-11-23 RU RU2002113453/02A patent/RU2248870C2/ru not_active IP Right Cessation
  • 2000-11-23 BR BR0015916-6A patent/BR0015916A/pt not_active Application Discontinuation
• 2002
  • 2002-04-30 IL IL149428A patent/IL149428A/en not_active IP Right Cessation
  • 2002-05-03 ZA ZA200203504A patent/ZA200203504B/en unknown

Patent Citations (6)

Non-Patent Citations (1)

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