Abstract: A method and an apparatus for conducting predetermined operations in the interior of a pipe with a cutter, in which the cutter is shifted so that a rotary axis of the cutter is angularly displaced about an axis extending along the pipe and is displaced in the axial direction of the pipe while the cutter is rotated about an axis extending in the axial direction of the pipe or about an axis extending in the radial direction of the pipe.

Abstract: A drilling device for drilling holes in structural steel shapes utilizes a control system having a pair of control pistons to set the drill bit at an optimum distance from the workpiece for repeated drilling of holes through material of a given thickness. The control device responds to position switches sensing the positions of the drill-feed cylinder and the control pistons.

Abstract: A tapping attachment for threading a relatively large number of holes through a sheet metal part at a relatively low cost per hole. The tapping attachment includes a thrust bearing assembly which is aligned with a turret-type punch press or the like and movable in response to an axially directed force generated by the punch press. The axially directed force applied from the press to the thrust bearing assembly is transferred to a spline shaft. The spline shaft is rotated wihin and moved linearly relative to a screw threaded roller nut, whereby the axially directed force is converted into a rotating force for advancing and turning a tap at high speeds of rotation. A nitrogen reservoir is provided so that a supply of gas is available for returning the thrust bearing assembly and the spline shaft to their initial positions in order that a new hole can be tapped in response to another axially directed force.

Abstract: A drilling unit comprises a housing (5), a drilling spindle housing means (3) axially moveable within said housing (5), a drilling spindle (2) rotatably received within said housing (5) and driven by a driving means (12), a plunger (15) connected to the drilling spindle housing means (3) and piston means (22) slideably received within said housing (5) and operatively connected to the plunger (15). The plunger (15) is connected to the piston means (22) with a first clearance (51) in a plane normal to the direction (A) of the axial movement of the plunger. The piston means (22) further is connected to the plunger (15) with a second clearance (52) in the direction of the axis (A) of said drilling unit.The drilling unit exhibits excellent linearity of axial motion combined with a high degree of accuracy and, at the same time, requires as little space as possible in a plane parallel to a plane, in which a workpiece is positioned.

Abstract: A milling and countersinking fixture for machining cylindrical openings includes a spindle head having a central opening formed therein and a tool holder disposed on the spindle head having an end surface and having a central opening formed therein defining an inner surface. A clamping mandrel is supported in the central opening formed in the spindle head and guided through the central opening formed in the tool holder. The tool holder has at least one recess formed therein having a given cross-sectional shape and is open only toward the end surface and toward the inner surface. At least one cutting body has a cross-sectional shape adapted to the given cross-sectional shape for insertion in the at least one recess.

Abstract: A drilling unit comprises a housing (5), a drilling spindle housing means (3) axially moveable within said housing (5), a driling spindle (2) rotatably received within said housing (5) and driven by a driving means (12), a plunger (15) connected to the drilling spindle housing means (3) and piston means (22) slideably received within said housing (5) and operatively connected to the plunger (15). The plunger (15) is connected to the piston means (22) with a first clearance (51) in a plane normal to the direction (A) of the axial movement of the plunger. The piston means (22) further is connected to the plunger (15) with a second clearance (52) in the direction of the axis (A) of said drilling unit. The drilling unit exhibits excellent linearity of axial motion combined with a high degree of accuracy and, at the same time, requires as little space as possible in a plane parallel to a plane, in which a workpiece is positioned.

Abstract: An apparatus for boring a laminated plate includes a table having a first surface on which a laminated plate may be placed for boring and an opposing second surface, the table defining at least one passage therethrough; a supporting pad for urging a laminated plate to be bored towards the first surface of the table; and a cutter for boring a laminated plate to be bored, the cutter operable to bore in a direction generally opposite to the direction that the supporting pad urges and through the passage defined by the table. Further according to the present invention, the cutter includes a knife edge, a pivotal mechanism adapted to be pivoted about its axial center line, and a stepping mechanism for moving the knife edge in one direction and unsuccessively further in a second direction so that successively deeper boring may be performed.

Abstract: A drive shaft rotated by an electric motor is disposed to penetrate through a main body, and a spindle is concentrically mounted at the distal end of the drive shaft so that the rotational force of the drive shaft moving in an axial direction thereof is transmitted to the spindle. A processing drill head is selectively mounted at the distal end of the spindle that is coupled with a piston which is urged to a first position in an axially forward direction of the spindle by the fluid pressure supplied to a cylinder, for executing a processing work and a retreated position at which a hold mode is set. An abutting member is securely fitted to the outer surface of a piston rod, and a ring-shaped magnetic member is further provided to the outer surface of the piston rod in an axially movable manner, this ring-shaped magnetic member always being urged in the retreating direction.

Abstract: A power tool combination including a hammer drill, an adapter secured to the drill for attaching it to an elongated rod which bears on the floor, a pneumatic cylinder and piston unit mounted between the elongated rod and the drill for applying an uniform external force for moving the power drill into the ceiling, and a coupling member between the pneumatic piston and cylinder unit. The coupling member is rigid for transmitting axial forces therethrough under normal operating conditions but is capable of yielding to absorb abrupt shock forces in the event that the drill encounters an undesirable obstruction in the ceiling, the coupling member including structure for causing it to return to a normal rigid condition after the shock forces have been absorbed.

Abstract: A doweling tool for drilling a dowel hole in concrete to facilitate the insertion of dowels, the doweling tool having a guide bar, a support frame for supporting the guide bar, a carriage movingly connected to the guide bar, a pneumatically operated drilling tool having a drill bit connected to the carriage and a pneumatic cylinder having a portion connected to the support frame and another portion connected to the carriage. The pneumatic cylinder is operable to move the carriage and the drilling tool connected thereto in a forward direction for drilling the dowel hole and for moving the carriage and the drilling tool connected thereto in a reverse direction for withdrawing the drilling tool from the dowel hole. The carriage is rollingly supported on the guide bar by a roller assemblies for rolling movement in the forward and reverse direction.

Abstract: Tapping apparatus comprising: a body (5) suitable for being mounted on a moving element (4) of a press; a system of multiplying gears (14) having their axes parallel to the direction (F) of motion of said element, and placed on said body; a motion transforming device having a large pitch screw (26) and nut (27) for transforming the linear stroke of said element into a rotary motion which is applied to a first gear wheel of the system; and a tapping head (18) which is rotated by the last gear wheel (17) of the system and which is driven in translation by the body, said head comprising a fixed casing (32), a spindle (36) which pivots in said casing and is rotated by the last gear wheel (17) and a tool-carrying clamp (51) which is rotated by the spindle and which is capable of longitudinal displacement against pneumatic return means (F.sub.d) of adjustable force.Applicable to machine tools.

Abstract: A hand-held drill is provided that has a pneumatically operated drill motor. A portion of the air that operates the drill motor is directed against the drill motor housing to slidably move the housing within an outer casing to provide a constant feed of the drill bit. The feed rate is controlled by a rate limiter axially aligned with the drill motor and including a piston attached to the drill motor, the piston being mounted within a cylinder filled with hydraulic fluid. The piston has a bore formed through it that permits flow of hydraulic fluid through the bore and a flow control valve is placed within the bore that controls the flow of fluid through the bore to limit the rate of movement of the piston through the hydraulic fluid and thereby control the rate of movement of the drill motor through the casing. Preferably, the drill includes a vacuum collar surrounding the drill bit to remove dust and material particles from the workpiece.

Abstract: An apparatus for drilling sheet material comprises a reciprocating subframe which rotatably supports an annular drill and pressing means. The pressing means holds the material down during drilling and strips the material from the drill when the subframe is raised.

Abstract: A thread cutting work station includes a carriage assembly mounted on guideways for guided movement under the control of a linear actuator between an initial, home position and a forward position for cutting threads in or upon a workpiece. A collet is connected to a drive motor and carries a tap for thread cutting. In operation, the linear actuator accelerates the carriage assembly from the initial, home position along the guideways towards the workpiece with the rotating tap entering the to-be-threaded bore to initiate the thread cutting operation with the subsequent feed rate controlled by the rotating tap. After completion of the thread cutting step, the drive motor is reversed to withdraw the tap from the threaded bore, and the linear actuator is controlled to rapidly move the carriage assembly to its initial position.

Abstract: The invention relates to a feeding device for a tool slide of a machine tool of a simple, compact and economical construction comprising an electro-hydraulic linear amplifier easily accommodated in the constructional space of a hydraulically operated tool slide. The valve housing is inserted into the piston rod on the side of the piston remote from the control valve means thereby allowing for a plurality of tool slides to be arranged in a very compact space. The valve means forms a cartridge which can be simply inserted into the cylinder chamber formed by the cylinder housing. The arrangement of the control valve means in the cylinder housing and the rigid connection between the motor and the piston result in compact design and in shorter conduits for the hydraulic fluid between the control valve means and the cylinder chambers thereby leading to a high rigidity of the feeding device.

Abstract: A deep-bore drilling machine consists of a deep-bore drilling unit (1) which is driven by rotation and has a deep drill tool (4, 7). The front end (7) of the deep-bore drilling tool (4) is led into the drill bushing (10) at the beginning of the drilling operation. The drill bushing (10) is thereby contained in a main spindle (22) and is replaceable. Also, the main spindle (22) can also be driven independent of drive (2) of the deep-bore drilling unit (1) by another drive (30).

Abstract: A hydraulic control system for a downhole sidewall coring tool having first and second power hydraulic systems in which changes in pressure drop in a portion of the first hydraulic system adjusts a control valve to change the pressure in a part of the second hydraulic system. Means are provided to adjust the operation of the control valve as a function of viscosity change in the hydraulic fluid caused by change in ambient temperature.

Abstract: A power drill system is disclosed which is hand held and manually operable. The drill system includes a drill and a positive feed unit for the drill connected thereto. A clamping member is connected at a lower portion thereof to a housing for the drill and feed unit. The clamp member is pneumatically powered to move it against a workpiece and clamp it against the housing at the location of the drill. A four way toggle switch controls the air pressure to the clamp member allowing the operator to control the clamping operation with one hand while the other hand holds the housing in the desired position.

Abstract: A turret coupling (13) for locking a tool (10) in a desired angular position relative to a workpiece (16), where the tool is locked onto the workpiece by a fixture (19) through a nose piece (12), is comprised of a sleeve (13a) notched on the rim. The sleeve is closely fitted over the lower end of the tool, or a nose adapter (25), and held by a retainer (13b) threaded into the tool or the adapter. A latch key (24) locks the tool to the sleeve. To reposition the tool relative to the nose piece, a shaft (28) is lifted by a lever (26) having a return spring (22) under a button (21).

Abstract: Drilling apparatus is adapted for use with a computer controlled plotter to selectively use the plotter as an automatically positionable hole drilling device. A drill motor of the drilling apparatus is carried and manipulated by a carrier mechanism of the plotter in a manner similar to that in which a conventional plotter instrument is manipulated. A coupling apparatus is attached to the carrier mechanism for the purpose of selectively mechanically connecting to and establishing a pneumatic seal for supplying pressurized gas to operate the drill motor. An alignment apparatus is connected between the carrier mechanism and the drilling apparatus to position an axis through the drill bit of the drill motor orthogonal to the plotter table. An actuator apparatus moves the drill motor toward the plotter table to drill holes in the material positioned on the plotter table.

Abstract: An improved right angle drill including a pneumatically powered motor and feed and retract apparatus driven by the motor. The feed and retract apparatus includes a control valve for controlling the flow of pressurized air to the motor and to the feed and retract apparatus to automatically stop the feed motion, to automatically stop the retract motion, and to stop the drill completely.

Abstract: A tool holder for holding a rotary cutting tool, attachable to a spindle of a machine tool, has a holder body fixed to the machine spindle. A rotatable shaft having a tool-mounting portion is coupled to the holder body such that the shaft is axially and radially displaceable relative to the holder body. A positioning member is fixedly disposed on the machine tool body radially outwardly of the machine spindle. A casing is disposed radially outwardly of the rotatable shaft such that the casing and the rotatable shaft are rotatable relative to each other, the casing being engageable with the positioning member to accurately position the rotatable shaft when the holder body is fixed to the machine spindle. A guide bushing is fixedly supported at one axial end portion of the casing remote from the holder body.

Abstract: A hand-held pneumatic-hydraulic drill unit employs modular drilling and clamp-up assemblies to perform a complete drilling cycle. The drilling cycle consists of: (1) clamping the drill unit to a work piece and/or a template that positions the drill unit relative to the workpiece; (2) advancing a rotating tool bit to perform the desired machining operation; (3) withdrawing the tool bit from the machined opening; and (4) releasing the clamping mechanism that secures the drill unit to the workpiece. The drill unit includes a pneumatic motor subassembly that is advanced toward and retracted from a workpiece by a hydraulically actuated feed cylinder. The motor subassembly and feed cylinder are axially aligned with one another. The clamp-up assembly of the drill unit also includes a clamp cylinder that is activated solely by hydraulic pressure. A modular, pneumatically actuated hydraulic pump is mounted on the drill unit and supplies pressurized hydraulic fluid to the feed and clamp cylinders.

Abstract: In effecting positioning of a workpiece relative to a working tool, indexing is carried out by obtaining precision measurement of the relative distance between the workpiece and the working tool by using a laser beam. Positioning can be effected with improved precision and working can be achieved with improved dimensional accuracy.

Abstract: A baseplate carries an axially-advanceable rotating cutter. A V-block and clamp head are aligned on the plate to locate and secure a robot-positioned welding torch nozzle in a vertical attitude. After clamping the nozzle in position, the rotating cutter is advanced into the nozzle bore to remove accumulated internal weld spatter. The machined-away weld spatter can therefore be discharged under the influence of gravity or by a blast of purging air applied to the torch nozzle.

Abstract: A boring, skiving, and roller burnishing tool includes means for boring, skiving, and burnishing a cylindrical hole in a workpiece. The boring means comprises a plurality of cutting blades oriented at a particular angle to remove a relatively large amount of material from the hole. The roller burnishing means includes a roller race having a central axis and a frustoconical outer surface tapering radially outward and axially forward. Rollers are arranged about the outer surface of the race for rolling engagement with the internal surface of the hole. The smaller ends of the rollers face forward, and the taper of the rollers is such that the outermost surface portion of each roller is parallel to the central axis of the race. The rollers are biased in the forward direction using a roller pusher with a chosen force so that the force exerted on the internal surface of the hole remains constant over a range of sizes of the hole.

Abstract: A mechanical tool manipulating method and apparatus including apparatus and process for splitting axes of drive, wherein the drive means include preloaded lead screw nuts for minimal backlash, and "v" wheels and cylindrical slides for lineal tracking, as well as apparatus and process for precision clamping of the workpiece, and for recirculating exhaust air for clearing debris.

Abstract: A device for removing plugs from plugged tubes in a steam generator including a frame having a substantially flat plate, with a hollow drill bit mounted thereon and movable generally perpendicularly with respect thereto from a storage position to an operating position. An elongated retaining pin extends through the hollow drill bit and therebeyond having threads on one end thereof for attachment to the plug to be drilled. Actuating means moves the drill bit between the storage position thereof and the operating position thereof, motor means is mounted on the frame for rotating the drill bit. An air-water mixture is introduced near where the drill bit meets the plug to be drilled, the water being present in an amount of about one-half volume percent, and a vacuum is used to collect and remove the air-water mixture and any debris entrained therewith due to drilling the associated plug.

Abstract: The invention pertains to a boring tool for boring cylinder chambers of internal combustion engines without removing the engines from the vehicle chassis. A housing affixed to the engine block includes a rotatable driveshaft supporting a cutting tool whereby rotation of the driveshaft by an electric motor causes linear movement of the driveshaft to feed the tool. Tool advance is produced by a spiral groove pump defined upon a piston mounted on the driveshaft located within an oil-filled cylinder defined in the housing. A valved fluid passage located in the driveshaft piston selectively permits the pump to be bypassed for axial rapid traverse movement of the driveshaft and tool.

Abstract: A method and machine for machining the surface of a valve seat (3) which is required to have a very accurate alignment with respect to a guide bore of a valve guide (2).In order to be capable of machining the valve seat surface in high roundness while maintaining a high concentricity with the guide bore, a pilot member (4) is moved forward inclinably to catch a guide bore of a valve guide (2) at its front end; the pilot member is further moved forward bendably while following the guide bore; when the pilot member has reached the desired position, the posture of the pilot member in the position is firmly held; and the surface of the valve seat (3) is machined by moving edged tool members (5a) forwardly while rotating the edged tool members (5a) which are arranged coaxially with the pilot member.

Abstract: A feed rate attachment for a drilling tool or the like. The drilling tool is equipped with a piston attached thereto operating within a cylinder positioned against the work-piece. A hydraulic damper is utilized to linearly resist the movement of the drilling tool attached piston relative to the cylinder.

Abstract: An automated control system and method for control of hydraulically positionable machine tools is disclosed. A servo motor is coupled to a servo valve spool such that the angular displacement of the motor shaft directly corresponds to the resultant rotation of the spool, which in turn threadably engages a precision lead screw fixed to a tool slide. In the preferred embodiment, a position encoder provides signals indicative of the angular displacement of the motor shaft. The position encoder signals are fed back to an electronic central processor which controls motor operation. The controller is programmed with the lead screw pitch information, and a series of instructions to advance or reverse the spool along the lead screw in a series of movements precisely corresponding to the desired movements of the slide.

Abstract: A chamfering apparatus for opposing end faces of a tubular member. The apparatus includes an abutment member capable of advancing toward or being retracted from a line of extension of the longitudinal axis of the tubular material so as to collide with the end face when advanced, a conveyor for transporting the tubular member toward the abutment member, a chuck provided between the abutment member and conveyor for releasably holding the tubular member on the conveyor, and a cutting tool displaceable relative to the end face of the tubular member received by the abutment member and held by the chuck. The cutting tool is capable of rotating around the longitudinal axis of the tubular member.

Abstract: A portable lathe for machining the end of a pipe workpiece for butt welding, having a cylindrical shroud with a collar for receiving the workpiece and three equiangularly spaced, hydraulic clamps mounted on the collar for clamping the pipe workpiece therein coaxial with a rotary cutting tool support of the lathe. Three equiangularly spaced, hydraulic actuators provide for axially feeding the tool support during machining and are hydraulically interconnected for damping an unbalanced machining reaction force on the cutting tool support.

Abstract: A positive feed drill has an elongated spindle mounted for reversible longitudinal motion in a drill housing. The spindle has a hexagonal cross-section with the apices of the hexagon being threaded. A toothed drive gear having a hexagonal aperture centrally thereof has a close sliding fit with the spindle for imparting rotation thereto. A feed gear threadedly engages the spindle apices and is selectively rotated at a different rotational speed than the drive gear to correspondingly longitudinally advance and retract the spindle. A pneumatic circuit provides completely automatic drilling to an adjustable depth and a positive retraction of the spindle. This circuit is novel in that it is contained internally within certain of the drill frame members.

Abstract: A drill employed for drilling holes in airframes is provided with means to rotate the drill bit during retraction and means to control the rate of retraction of the drill bit from the hole in a manner to prevent the formation of axial scratches in the wall of the hole.

Abstract: Apparatus is described for insertion into a branch pipe to cut an aperture in a liner provided within the main pipe for repairing the latter. The apparatus has a body together with a cutting device and a clamping member (e.g. an inflatable sleeve) both supported by the body. Means are provided for actuating the clamping member so that it presses against the inside of the branch pipe and jams the body in a fixed position within the branch pipe. The cutting device may be advanced relative to the body, to cut an aperture in the liner. Also described is an inflatable plug which may be used to provide a seal so that a grouting operation may be performed without grout being able to escape into the branch pipe or into the interior of the liner.

Abstract: A cutting tool is operatively connected with the piston of a tool positioning cylinder so as to move in response to axial movement of the piston. One end of the cylinder is connected with one end of a stroke limiting cylinder to form a closed fluid circuit therebetween. The piston of the stroke limiting cylinder has a predetermined adjustable stroke. A metering system is provided for injecting or extracting incremental fixed volumes of oil to and from the closed fluid circuit to increase or decrease the stroke of the piston in the tool positioning cylinder and thereby vary the depth of cut of the tool.

Abstract: The machine tool provided with a machine frame adapted to be attachable to a stand, a pneumatic cylinder for reciprocating a quill on the machine frame, and a feed control device for controlling the forward moving speed of the quill comprising a hydraulic cylinder which is parallelly disposed to the quill and includes a piston assembly having a projecting portion engageable with the quill and a liquid tank. The quill is moved, until it is engaged with the projecting portion in the forward moving thereof, at a rapid feed speed and after the engagement at a controlled feed speed by the feed control device. The liquid tank has a pair of openings arranged such that either one of the two may constantly come under the liquid surface in the tank no matter in what posture the machine frame may be attached to the stand.

Abstract: A skiving and roller burnishing tool for cutting and burnishing the interior of a cylinder or other workpiece is disclosed. The cutter assembly is mounted on a drive shaft which drives the cutter assembly through the interior of the cylinder to cut the interior of the cylinder to its approximate final diameter. A roller race is located aft of the cutter assembly, and has a frustoconical configuration in section which tapers outwardly in a forward direction. A plurality of rollers are distributed circumferentially about and bear on the roller race. The rollers are also frustoconical in section so that the outermost surface of each roller is parallel to the axis of the drive shaft. A roller cage engages the rollers and restricts movement of the rollers while allowing them to rotate about their axes and translate radially to a limited degree. The roller cage is movable in an axial direction relative to the drive shaft.

Abstract: A power feed rotary tool, such as a drill or a tapper, has an electric motor for rotating the working head and a pneumatic system for advancing the working head. A control rod extends from one end of the tool housing, and is displaced together with the working head, but does not rotate. The control rod controls the feed stroke of the working head. The electric motor is connected to the tool housing between its ends.

Abstract: A drilling machine comprises a quill, pneumatic cylinder for reciprocating the quill in the forward and backward direction, a feed control device which includes a liquid cylinder parallelly disposed to the quill and provided with a piston assembly with a projecting portion engageable with the quill for controlling the advancing speed of the quill, one-way clutch for allowing the piston assembly only the forward movement thereof by engaging with the projecting portion of the piston assembly, and an operation control device for repeatedly reciprocating the quill. The quill is advanced firstly at a rapid speed; upon engaging with the projecting portion of the piston assembly, the quill is advanced at a regulated speed by the liquid cylinder. When the quill has completed several times of reciprocation movement under the control of the operation control device, one working cycle is finished.

Abstract: This invention relates to an improvement in a hand drill with a pneumatically-hydraulically controlled advance and including a housing, a drilling drive unit adapted to be powered by compressed air and being displaceably guided in said housing by a piston and cylinder, and further including hydraulic lines, and control valves, the improvement comprising a rotatable support sleeve means secured to said housing and adapted to rest on the surface of a workpiece and surround a drill bit, said piston being a double-faced hollow advance piston means mounted in said cylinder so as to divide said cylinder into two chambers, one chamber together with one face of the advance piston means being adapted to be acted on by the compressed air, and the other chamber being adapted to be filled with hydraulic fluid and pressure-loaded by the other face of the advance piston means, said latter chamber communicating through hydraulic line means and a throttling back-pressure valve means with a cylinder means having a compensatin

Abstract: The tool includes an elongated body, rectangular in cross-section and having a switch housing mounted on one side face, to enable the mounting of an array of such tools in close side-by-side relation. A hydraulic motor, rotary drive spindle, and extensible quill are mounted relative to the housing about a common rotary and extension axis. The drive spindle has an external spline at its rear end, for engagement with an internally splined drive coupling which is secured to the motor drive shaft by means of a special key arrangement to prevent axial movement of the drive coupling. The quill is extended by a fluid operated cylinder-piston structure; and the front end of the drive shaft is supported within the front end of the quill by means of a uniquely mounted bearing. The bearing is mounted at the squared front end of the quill for precise axial and squared alignment; and is also confined between the spindle drive shaft and spindle end for precise axial and squared alignment relative to the spindle.

Abstract: An automatic hydraulic stop for use with a numerical control machine and cutting tool. The stop senses the distance to a work piece, limits the depth of penetration of the tool into a work piece and provides protection for inadvertent travel of spindle of the numerical control machine beyond a projected point.

Abstract: A positive feed drill having an elongated spindle mounted for reversible longitudinal motion in a drill housing. The spindle has an hexagonal cross-section with the apices of the hexagon being threaded. A toothed drive gear having a hexagonal aperture centrally thereof has a close sliding fit with the spindle and is mounted for rotating the spindle. A feed gear having a threaded aperture centrally thereof is in threaded engagement with the spindle apices and is selectively rotated at a different rotational speed than the drive gear to longitudinally advance and retract the spindle. A gear for driving the feed gear is pin-slot locked to a motor gear for longitudinal spindle advancement, and is pin-slot locked to the housing for rapid spindle retraction. A pneumatic circuit in cooperation with limit valves and stop members provides completely automatic drilling to an adjustable depth, a dwell, and a positive retract operation with an economy of pneumatic energy.

Abstract: A method of and an apparatus for forming by frictional heat and pressure a bossed hole in a metal plate or a tube wall with the aid of a rapidly rotating piercing tool, of which the axial feed is controlled, in such a manner, that during a predetermined time from the point of time, at which the tool comes into contact with the plate or tube wall the axial movement of the tool is slower and after that time said movement is faster than a movement of given speed.

Abstract: A carriage and guideway unit for a machine tool having a carriage carried by a pair of laterally spaced apart ways with a central portion of the carriage extending between and longitudinally of and bearing on the ways to align the carriage for longitudinal sliding movement along the ways. The carriage is reciprocated on the ways by a drive means having an actuator rod extending between the ways and connected to the carriage such that the centerline of action and reaction between the drive rod and the carriage is centered between and extends longitudinally of the ways and is in the plane of the faces of the ways carrying the carriage.

Abstract: In an automatic screw thread cutting machine having a clamping carriage for clamping an elongated workpiece, one end portion of which is to be provided with a screw thread, and a spindle coaxially arranged with a workpiece held by said clamping carriage and carrying at one end thereof facing the end portion of the workpiece a screw cutting tool and being driven over a stepdown gearing from a motor, an advancing mechanism for advancing the clamping carriage towards said spindle and including a rod connected to the carriage and having a pair of opposite smooth parallel friction surfaces and a friction wheel driven by the spindle and pressed against one of the friction surfaces while the other friction surface is engaged by a counter roll. The friction wheel is exchangeble against a friction wheel of different diameter to thereby change the speed of advancement of the carriage.

Abstract: A positive feed drill having an elongated spindle mounted for reversible longitudinal motion in a drill housing. The spindle has an hexagonal cross-section with the apices of the hexagon being threaded. A toothed drive gear having a hexagonal aperture centrally thereof has a close sliding fit with the spindle and is mounted for rotating the spindle. A feed gear having a threaded aperture centrally thereof is in threaded engagement with the spindle apices and is selectively rotated at a different rotational speed than the drive gear to longitudinally advance and retract the spindle. A gear for driving the feed gear is pin-slot locked to a motor gear for longitudinal spindle advancement, and is pin-slot locked to the housing for rapid spindle retraction. A pneumatic circuit in cooperation with limit valves and stop members provides completely automatic drilling to an adjustable depth, a dwell, and a positive retract operation with an economy of pneumatic energy.