Abstract: Drill with a straight chucking groove, with a convexly curved main cutting edge with, adjacent to the main cutting edge, a convexly designed region of groove base and with, adjacent to the convexly designed region of the groove base, a concavely designed groove base or a concavely curved main cutting edge with, adjacent to the main cutting edge, a concavely designed groove base with, adjacent to the concavely design region of the groove base, a convexly design region of the groove base.

Abstract: A reamer has a center axis and includes a single cutting edge, provided for a cutting part that is arranged at a leading end side. The reamer includes three guide pads in the cutting part. The first guide pad is formed so as to project to the side almost opposite that where the single cutting edge is formed. The second guide pad is arranged in one area of areas, along a peripheral face of the cutting part, that are located between the first guide pad and the single cutting edge and that are directed toward sides opposite each other, and the third guide pad is arranged in the other area.

Abstract: A support pad intended for metal machining drills and of the type that includes an outer surface, an inner surface, front and rear end surfaces, as well as a pair of spaced-apart side surfaces, between the outer surface and at least the front end surface a convexly arched entering surface being formed that extends between, on one hand, a pair of front and rear borderlines, the rear one of which borders the outer surface, and, on the other hand, two tangentially spaced-apart side borderlines. The rear borderline of the entering surface has the shape of a convex arc line as viewed in planar view toward the outer surface, more precisely an arc line the crest of which is facing forward. In such a way, the position of the contact of the support pad with a hole wall can be predetermined in an exact way. The drill body may be equipped with one or more support pads.

Abstract: An insert attached to a tool body of a hole machining tool having an attachment seat and a pressing member for pressing the insert to adjust the position of a peripheral cutting edge in a diameter direction of the tool. The insert has a panel shape. One surface of the insert in a thickness direction provides a seating surface, the other surface in the thickness direction provides a peripheral flank surface. A surface facing the rear side of the insert in a tool rotation direction provides a pressed surface in a state that the insert is attached to the attachment seat. A side surface facing the front side in the tool rotation direction provides an inclined surface, and a peripheral cutting edge is formed at a ridge portion outside of the inclined surface in the diameter direction of the tool.

Abstract: A gun drill guide is disclosed comprising a cylinder body member of a resilient polymer material having a central opening extending therethrough, a radially extending flange means at one end thereof to engage the end face of a bearing assembly and an annular groove near the opposite end thereof defined by second and third radially extending flanges for engaging the opposite end face of the bearing assembly. A locking member, a chip deflector assembly, a stabilizer assembly or other guide attachment are disclosed which may be attached to the drill guide.

Abstract: A drilling head for a tubular shank having an inside diameter and threads may comprise an axial body comprising a duct exiting through a first end; threads adjacent the first end corresponding to the threads on the shank and aligning the duct with the shank inside diameter; a bore from an outer surface of the body to the duct; and two axially extending approximately parallel and offset surfaces adjacent a second end; and an insert affixed between the offset surfaces, the insert comprising: a first face at least partially contacting one offset surface and a second face at least partially contacting the other offset surface; one or more cutting edges adjacent the first face, the second face, or both; and a cutting lip adjacent one or more cutting edges.

Abstract: A cutting tool of the sort used for deep hole drilling has a cutting head mounted on a shank. The cutting head is formed asymmetrically with respect to a longitudinal axis and has at least one cutting edge. The cutting head has guiding segments that extend from a forward end to a rear end of the cutting head. Each of the guiding segments has a guiding pad in the periphery thereof. A forward end of the guiding pad lies on a cylindrical envelope defined by the cutting diameter of the cutting tool. A rear engagement portion of the cutting head is engaged with a forward engagement portion of the shank. The cutting head is made from sintered carbide powders and the guiding pads are integrally formed with the cutting head.

Abstract: A short-hole drill, including a drill body being rotatable about a center axis and having a rotationally symmetrical envelope surface, one or more replaceable cutting inserts mounted in pockets in a front end of the drill body, one or more outwardly open flutes being countersunk in the envelope surface and extending rearwardly from the front end of the drill body to evacuate chips from the cutting inserts, and a number of replaceable first support pads being mounted in countersunk seats proximate the front end of the drill body to support and guide the drill against a hole wall generated by the cutting inserts. A number of second support pads are mounted in countersunk seats that are axially spaced apart from the first support pads by an envelope surface portion having a predetermined axial extension to support and guide the drill when the first support pads leave the hole wall.

Abstract: A recess and an attachment seat are formed in a front end of a tool body. A panel-shaped insert attached to the attachment seat where the thickness direction is matched with the diameter direction of the tool body and a surface of the insert facing the rear in a tool rotation direction becomes a pressed surface. A peripheral cutting edge is formed at a ridge of an inclined surface on the outside in the diameter direction of the tool body, a bevel edge is formed at a ridge on the front side of the tool body, and a back taper is attached to the peripheral cutting edge. A pressing member for pressing the pressed surface of the insert to adjust a position of the peripheral cutting edge in the diameter direction of the tool body is disposed on the rear side of the attachment seat in the tool rotation direction.

Abstract: A deep-hole boring machine (100) includes a base (11) to be fitted to an upper face of a floor, a pillar (14), a fixing mechanism (40), a guide member (15), a rotary tool (17), a tool rotation driving section (16), a rising/descending mechanism (50), a guide base (60) and a tool guide mechanism (30). The deep-hole boring machine 100 can be used to bore a vertical hole or an inclined hole in a concrete in a construction site.

Abstract: There is provided a method for machining a deep hole, which enables prevention of scattering of a coolant and efficient discharge of shavings. The deep hole machining method includes: feeding a spindle to a deep hole machining start position while jetting a coolant toward a workpiece from an external normal pressure coolant supply line; closing the external normal pressure coolant supply line and opening a spindle normal pressure coolant supply line at the start of machining of a deep hole, and machining the deep hole to a predetermined intermediate depth while supplying a coolant to a machining point; and closing the spindle normal pressure coolant supply line and opening a high-pressure coolant supply line when the depth of the hole machined has reached the intermediate depth, and machining the deep hole to the final depth while supplying a high-pressure coolant to a machining point.

Abstract: The invention provides a drill head for deep hole machining capable of raising circularity and straightness of a hole and improving precision of hole machining. In the drill head for deep hole machining constituted by fixing a cutting blade to a tip surface of a head body and fixing guide pads to a periphery of a tip of the head body, the length Lm of a margin, which is formed at a tip side of a periphery of the cutting blade in a drill rotating direction, in an axis direction is made substantially the same as the length Lp of the guide pads in the axis direction, and a top end and rear end of the margin are substantially aligned with a top end and rear end of the guide pads, respectively, in a circumference direction.

Abstract: A deep hole boring head is provided which is capable of rotating about a central axis, a body whose front part has at least one cutting edge followed by a recess which leads to a duct inside the body, this duct allowing the chips formed during the boring to be cleared away rearwards, and includes at a front end thereof and at a center portion thereof a pilot drill bit capable of guiding the head during boring. Use for the boring of a production piece is made of titanium, the ratio L/D between the depth L of the hole bored and the diameter D of the latter being greater than or equal to 10, and the diameter D being greater than or equal to 65 mm.

Abstract: A gun-drill comprises a cutting-head detachably secured to a shank, having a common longitudinal axis and comprising mating peripheral surfaces. A shank coupling portion comprises a forwardly tapering shank fixation surface is formed at a front end of the shank, and a cutting-head coupling portion comprising a forwardly tapering cutting-head fixation surface is formed at a rear end of the cutting-head. Both the shank and the cutting-head coupling portion extend over a peripheral coupling angle ? of more than 180°. The shank and the cutting-head are assembled by positioning the cutting-head leading face in front of the shank trailing face, slidably inserting the cutting-head coupling portion into the shank coupling portion laterally to the axis of rotation A and rotating the cutting-head relative to the shank in a direction opposed to the direction of rotation R so that the cutting-head coupling portion and the shank coupling portion interlock co-axially.

Abstract: An edge-carrying drill body intended for deep hole drilling, is rotatable around a central geometric axis and comprises a through-channel arranged for internal chip evacuation. The channel mouths in front and rear ends of the drill body. A front channel mouth is bridged-over by a bridge on which a plurality of cutting edges are formed, which edges are made integrally with the rest of the bridge. The front mouth includes inlets disposed in front of respective cutting edges with reference to the direction of rotation of the body.

Abstract: In a first aspect, the invention relates to an edge-carrying drill body (1) of the type that is intended for deep hole drilling, and which is rotatable around a geometric axis (C) as well as comprises a through channel (2) arranged for internal chip evacuation, which channel mouths in front and rear ends of the body. Characteristic of the invention is that one or more cutting edges (4) are made integrally with the rest of the body, more precisely from a hard material, such as cemented carbide or CERMET. In a second aspect, the invention also relates to a method for the manufacture of such a drill body. In a third aspect, the invention furthermore relates to a drilling tool for deep hole drilling.

Abstract: A gun drill guide is disclosed comprising a cylinder body member of a resilient polymer material having a central opening extending therethrough, a radially extending flange means at one end thereof to engage the end face of a bearing assembly and an annular groove near the opposite end thereof defined by second and third radially extending flanges for engaging the opposite end face of the bearing assembly. A locking member, a chip deflector assembly, a stabilizer assembly or other guide attachment are disclosed which may be attached to the drill guide.

Abstract: A method of forming deep holes and a gundrill therefore is disclosed. The gundrill has an elongate tubular shank and a cutting tip, each provided with a tubular central region supplying pressurized drilling fluid and a non-circular fluid cross-section defining a drilling fluid return path in conjunction with the hole being formed. The cutting tip flute defines a primary rake surface terminating in an offset point, and a secondary flank surface for forming an outlet with the hole being drilled, sized to maintain fluid pressure in the bottom end space to cool the cutting surfaces and to effectively remove chips as they are formed. The drilling fluid exiting an orifice of the cutting tip, forms a maximum angle ? relative to the hole axis when viewed radially, which is greater than sixty-six degrees in order to minimize drilling fluid stagnation in an elongate fluid return path.

Abstract: A small drill includes one chip-discharging flute which is helically formed in the exterior surface of a cutting portion of the small drill. The small drill also includes a flute-shaped portion which is formed in the front region of the chip-discharging flute in the rotating direction, which is connected to the chip-discharging flute, and which is open at the exterior surface of the cutting portion. The core diameter ratio d/D, in percent, of the small drill is set to 60% or more, and a margin angle ? thereof is set to 120° or more.

Abstract: The present invention is to provide a machining tool bar in which mechanical machining properties are improved by using high stiffness composite material. According to the present invention, the tool bar includes an adaptor constructed to be coupled to a driving device, a body constructed to be mounted with cutting tools and a tip constructed to be supported by a workpiece, said body is constructed to be mounted with one or more cutting tools, wherein the adaptor and tip are made of metal material, the body is made of composite material having high stiffness, the composite material constructing the body is formed to surround at least a portion of the adaptor and at least a portion of the tip, and the metal material constructing the adaptor and tip and the composite material constructing the body are securely joined to each other in an interface therebetween.

Abstract: A deep hole drill for chip-removing drilling in a workpiece includes a body which has a cutting head and an integral cutting part. The body defines a longitudinal axis of rotation and has a longitudinal internal channel which opens into an end face of the cutting head for receiving cuttings that are entrained in a cooling medium. A chip removing insert is disposed on the cutting head. A support pad and a guide bar are disposed on a generally cylindrical outer peripheral surface of the cutting head and are arranged in circumferentially spaced relationship to one another. Cooling ducts are formed in the outer peripheral surface and are oriented generally parallel to the axis. The cooling ducts are open at the end face for conducting cooling medium thereto. The cooling ducts are situated adjacent the support pad and guide bar, respectively, for cooling same.

Abstract: A drill stem stabilizer used in a decoking apparatus that includes a drill stem and a drilling structure on which the drill stem is supported for vertical movement above and within a coke drum. The stabilizer includes a bearing and a support member. The bearing is adapted to guide the longitudinal movement of the drill stem. The support member extends laterally from the bearing and attaches to the drilling structure, and maintains the bearing in a position to guide the drill stem as it is moved into or out of the coke drum. In one embodiment, the drilling structure includes a pair of substantially vertical guide rails, and the support member attaches to the guide rails.

Abstract: An element which defines a support pad and/or a guide bar adapted to be mounted in a seat of a cutter head of a deep hole drill comprises a body which defines a longitudinal direction and a cross-direction. The body includes an inner mounting side and an opposing outer side. The outer side includes a contact surface which is adapted to engage a wall of a hole being drilled. The outer side also includes a countersink extending across the outer side in a direction transversely of the longitudinal direction. An edge of the contact surface facing toward a center of the body forms an angle with the longitudinal direction in the range of 55°±10°.

Abstract: A method for reaming a hole in a metal substrate that minimizes the tendency of long and stringy metal chips to be formed that can surround the reamer with a “steel wool-like” mesh or mass of material, as well as an improved reamer for carrying out this method. The reaming method involves longitudinally advancing the chamfered end of the reamer into the hole at an increased rate of at least about 5 mils (0.13 mm) per cutting edge as the hole is reamed during rotation of the reamer. For holes or bores having a length (L) that is at least about 3 times the cutting diameter (D) of the reamer, a preferred subsequent step is to momentarily reduce the rate of advance of the chamfered end into the hole to about 1 mil (0.025 mm) or less per cutting edge for from about 1 to about 5 rotations of the reamer.

Abstract: A system for boring a workpiece. The system has a spindle assembly for holding and rotating an elongate tool around a first axis to effect boring of a workpiece. The spindle assembly has a spindle that is movable from a retracted position along a first axis to an extended position through an operating range. The spindle assembly further has a guide assembly relative to which the spindle is guidingly rotatable. The system further includes a chip box having a housing defining a collection space and having first and second walls spaced axially relative to the first axis. The guide assembly and chip box are relatively movable along the first axis between first and second different relative positions, with the guide assembly and chip box being closer with respect to each other in the second relative position than in the first relative position. The guide assembly guides rotating movement of the spindle relative to the chip box with the guide assembly and chip box in the second relative position.

Abstract: A door drilling fixture is provided for drilling a long straight hole in a door from the hinge edge of the door to a through aperture of the door adjacent the latch edge of the door. The hole is for passing wires from the hinge edge to a device such as an electric lock in the aperture. The fixture ensures that the hole will run parallel to a broad face of the door by clamping to the door face at the hinge edge and at the aperture. The fixture includes an elongate body with a planar, non-marring bearing surface for clamping tightly against the broad face of the door. A set of drill bushings aligned along a drill axis parallel to, and spaced apart a fixed distance from, the bearing surface is mounted at one end of the body. A clamp assembly for clamping to the hinge edge is attached to the fixture adjacent the drill bushings. A second clamp assembly attached to the other end of the body passes through the aperture.

Abstract: A boring tool assembly is provided and has a cutting tool mounted on one end thereof and permits the boring of a straight hole through a member. The boring tool assembly includes a boring bar having integral guide members disposed thereon that follows behind the cutting tool and maintains contact with the machined surface just cut in order to keep the cutting tool in proper alignment. To permit the continued use of the boring bar after the outer diameter of the cutting tool has been reduced due to wear, each of the integral guide members are resiliently mounted on the boring bar. This permits the guide members to collapses inwardly to maintain a perfect fit with the pilot pore while maintaining bearing contact of the guide members with the pilot bore. The positive bearing contact helps to provide a dampening feature for the boring bar and a spring type force for the hardened guide members.

Abstract: A boring bit, especially a multi-blade boring bit. The bit preferably has a point symmetric cutting edge arrangement having main and secondary cutting edges that are tilted towards the axis of the boring bit. In order to stabilize the tool against vibrations cased by the cutting force, the secondary cutting edge is tilted along an effective length that is substantially axial in the direction of cutting thereby having a negative tool side rake.

Abstract: A gun drill having a reversed taper approximately ten times greater than the conventional drills, or approximately 0.3 mm per 100 mm, between a tip of the cutting edge and a point some distance away therefrom is provided. The gun drills deep holes at high speed and with sufficient exactness by preventing the peripheral surface of the gun drill from coming into contact with the inner surface of the hole being drilled.

Abstract: The drill bit according to the present invention provides an advanced, carbide tipped, coolant feed, two-fluted deep hole drill capable of drilling a wider variety of materials deeper and faster than presently known drills of similar construction. Specifically, a deep hole drill bit includes a cutting tip with a fitting end having "V" shaped profile with an apex edge extending along a plane which is substantially aligned with the cutting edges of the cutting tip. The drill bit additionally includes a drill shaft having a distal end adapted to be matingly fitted to the fitting end of the cutting tip. This joint structure allows the shaft to naturally push behind the drill tip to provide enhanced strength and support during drilling. In this manner, the contact area between the drill tip and the shaft is maximized, with the contact area being greatest towards the base of the "V", where the compressive forces are also greatest, i.e., along the cutting edges.

Abstract: A postage meter whose postage supply is a reel of adhesive tape on which is pre-printed a continuous incremental bar code. The amount of postage required for a given piece to be mailed is expressed on a postage label derived from the tape and attachable to the piece in multiple increments whereby the greater the postage amount, the longer the label. Also included in the postage meter is a second reel of blank adhesive tape from which is derived a data label to be applied to the piece on which is meter-printed data appropriate to the mailing, such as the identity the post office from which the piece is mailed and the date of mailing.

Abstract: Guide element for a cutting tool having a location hole (20) in the tool shank (4) having an internal thread (16, 10), which has a threaded bolt (14) having an external thread that can be screwed into the internal thread (16, 10) and is spring mounted in the screw-in direction when screwed in, and a guide head (13) fixed to a free end of the threaded bolt (14) and operating in the manner of a sliding rail.

Abstract: A metal cutting drill with replaceable cutting inserts and a length to diameter ratio of four to one or more. Two cutting inserts are positioned in exactly opposed diametric positions, and engage the workpiece in a substantially identical manner to precisely balance the radial forces resulting from drill axially advancing though a workpiece. Through the use of dual cutting inserts, the drill cuts the full circumference of a bore with each one-half revolution and therefore achieves the a faster axial feed rate. By virtue of the inserts being triangular, the curved corners on the cutting edges of the two inserts may be positioned relatively close together and yet sufficient space is left between the inserts to enable the drill shank between the inserts to be relatively thick and strong even at increased length to diameter ratios.

Abstract: A drill bit for forming holes in a printed circuit board. The drill bit includes a first end including a tip for contacting the material of the circuit board. A second end of the drill bit is attached to apparatus for rotating the drill bit. A cutting edge is in the vicinity of the first end. A pressure pad is opposite the cutting edge. A flute winds upwardly about the drill bit in a helix. An angle of the helix with respect to a longitudinal axis of the drill bit varies continuously, wherein the angle is about from about 15.degree. to about 35.degree. in the vicinity of the first end and increases with increasing distance from the first end to at least from about 35.degree. to about 65.degree..

Abstract: A drilling apparatus for penetrating material includes an elongated rotary tool for boring an aperture in a workpiece by turning about a longitudinal axis and for moving along the longitudinal axis relative to the workpiece during a cutting operation. The tool also includes a cutting head mounted on an end of an elongated, hollow shaft. A fluid circulation system brings a flowable substance temporarily into engagement with the workpiece during the cutting operation. The circulation system forces the flowable substance to flow in a passage defined by an external surface of the shaft and the workpiece toward the cutting head along an entire longitudinal length of the aperture being drilled. The flowable substance exits the aperture through the hollow shaft after flushing material from the cutting head.

Abstract: A method and apparatus for producing deep drill holes, particularly in wood and similarly structured materials, in which two drill elements, embodied as hollow shafts with cutting ends formed as cutting elements and concentrically disposed one within the other, are operated at different speeds, the cutting end of the interior drill element running behind the cutting end of the exterior drill element.

Abstract: A cutting edge 18 is provided on the end of a cutter tip 12 on a gun drill body 1. The cutting edge 18 has: a radially inner region providing a convex curved cutting edge portion 23, a radially outer region providing a straight cutting edge portion 19 and an intermediate region which provides a concave cutting edge portion 22 having a tapered portion 20 and a concave portion 21. The convex curved cutting edge portion 23, when viewed in the direction of the axis O, presents an arc shape, the radius R of the curvature of which is determined in relation to the outside diameter D of the gun drill so as to range from 0.1.times.D to 0.4.times.D. Thus, a gun drill is provided which exhibits an enhanced severing effect to cut metal chips into pieces so as to prevent clogging, as well as to prevent an increase in the cutting resistance, thus meeting the demand for a greater feed rate.

Abstract: A drilling tool has a drilling crown (12) removably arranged on a shank (10) at its front face, provided with two complementary regions that are mutually separated by chip channels (20) and that have partially circumferential surfaces (48). The drilling tool also has at least two cutting plates (14, 14', 16, 16') secured to the regions of the drilling crown and spaced apart by an angle of 180.degree., as well as a centering drill (26) centrally arranged in the drilling crown in the axial direction that projects over the front face of the latter. The cutting edge (18) of the outermost cutting plate (14) in the radial direction radially projects over the circumferential surfaces (48) of the drilling crown (18), whereas the working area of the innermost cutting plate radially approaches or overlaps the working area of the centering drill (26).

Abstract: A chuck assembly and drill tool for a deep hole drilling press wherein the shank of the drill is of great length and slidably received within the chuck assembly to various depths such that complete removal of the drill for the purpose of substitution with drills of different lengths is avoided. The invention also teaches means for securing the drill within the chuck at various points along the shank's length. Prevention of lubricating and cooling oil leakage is accomplished by novel packing means which are also incorporated into the chuck assembly. In another embodiment, a separate insert may be fitted to the chuck assembly to permit reception of shanks of varying diameter. Both embodiments prevent excessive vibration, fallout and whiplashing of the enclosed drill tool.

Abstract: A reamer includes a cutting tip mounted in the circumferential wall of the base body of the cutting head of the reamer, and at least one guide bead located in a groove formed in the base body and extending in the longitudinal direction of the base body. The guide bead has a contact surface containing at least regionwise a diamond material.

Abstract: A device for cutting the inner circumferential surface of a thick-walled small diameter pipe comprising a setting means for inserting a core bar having a cutting blade on one end thereof into a pipe to be processed, a rotating means for rotating said pipe to be processed set by the setting means about the axis thereof relative to said core bar, a feed means for cutting the inner surface of said pipe to be processed with said cutting blade while pulling the core bar which is securedly held at the other end thereof relative to said pipe to be processed, and a control means for controlling each of said means, providing a smooth high quality inner surface having excellent proof pressure against internal pressure.

Abstract: A cutting tool for making cylindrical bores includes two or More cutting inserts and radially or approximately radially directed blades which leave an uncut core, as well as chip removal devices extending in the axial direction of the tool. The cutting tool is composed of at least two coaxial parts. One part forms the boring crown with the cutting inserts, and the other part forms the support for the boring crown with a clamping shank. The chip removal devices extend axially along both parts and lead radially to the outside.

Abstract: A reamer includes a shank portion and a reamer head fixed to the shank portion. A cutting blade is mounted on the reamer head to project axially forwardly from the front end of the reamer head. A bearing guide pad is mounted on the reamer head circumferentially spaced from the cutting blade downstream with respect to the rotating direction of the reamer, and a sizing guide pad is mounted on the reamer head substantially diametrically opposed to the cutting blade. The axial lengths (L2) of the guide surfaces of the bearing guide pad and the sizing guide pad are both not larger than the axial length (L1) of the circle land of the cutting blade, the axial length (L1) of the cutting blade is not larger than the diameter (D) of the reamer, and the width (W2) of the sizing guide pad is not larger than the width (W1) of the bearing guide pad. The axial lengths (L2) of the guide surfaces of the guide pads are preferably 5 mm to 15 mm where the diameter of the reamer is 5 mm to 100 mm.

Abstract: Guide means are provided enabling a gun drill to be rotatably mounted in a supported bearing structure for operation with reduced bearing failure. The modified guide assembly provides a more effective seal means by reducing entry of chips and lubricant into the rotating bearing when machining a workpiece.

Abstract: The herein-proposed device includes a housing (1) provided with a hole (2) adapted to receive an arbor (3) carrying a cutting tool (4), a seal (8) mounted on the housing (1) in the zone of interaction between the cutting tool (4) and a workpiece (6) to be machined, pipings (16, 18) adapted for the supply and withdrawal of coolant, respectively, and a chip disposal opening (10). The device is provided with a safety valve (19) installed on the coolant supply piping (18). The housing (1) is provided with a seal (5) arranged in the zone of location of the arbor (3). The chip disposal opening (10) and a space (9) of the housing (1) are arranged on the opposite sides with respect to an end face (11) of the housing (1) in the zone of interaction between the cutting tool (4) and the workpiece (6) to be machined.

Abstract: A machine tool produces a tapered slot by moving a tool laterally of the workpiece as well as directly into it. The lateral movement is shortened at the end of each half reciprocation, so as to form the taper. The shortened stroke is achieved by use of electronic circuitry in which transducers are utilized to indicate by voltage output, the magnitude of movement of the tool into the workpiece relative to the magnitude of the movement of the tool laterally thereof and on positive or negative numerical pair being noted, deriving a further signal therefrom and utilizing it to change the direction of reciprocation.

Abstract: A portable line boring machine has a rotatable boring bar on which a tool bit is mountable. A first drive mechanism rotatably drives one end of the boring bar. A second drive mechanism linearly drives the first drive means and the boring bar along the longitudinal axis of the boring bar. A frame supports the first drive means, the second drive means and the boring bar.

Abstract: Method and apparatus for conducting boring of a series of spaced walls on a workpiece using a self-adjusting boring bar.

Abstract: A tool holder for a gun drill or reamer has internal and external cylindrical rear end pilot portions and a radial pilot flange for precisely connecting coaxially with a rotatable and axially moveable power source. A sleeve confined coaxially within the internal cylindrical portion has an axially extending flat spline surface for effecting driving engagement with a mating flat of a tool shank. A contractible conical split collet at the forward end of the holder coaxially clamps the tool shank when moved axially to a clamping position by means of a non-rotatable nut secured to the collet for cocking out of axial alignment therewith to assure precise coaxial clamping of the tool shaft. The nut is in screw threaded engagement with a rotatable and non-axially moveable collar provided with beveled gear teeth for rotation by a Jacobs type tool.

Abstract: A frame for rimless spectacles is provided which has no protuberances projecting from both surfaces of lenses, provides an improved effective field of view, and can be fabricated with ease. Blind holes are formed in nose- and temple-side edge surface portions of each spectacle lens, respectively. A pin-like projection is formed on each of nose-side and temple-side contact plates, and is inserted and fixed in the corresponding blind hole by using an adhesive.