Abstract: A worm shaft includes: an insertion portion; a wall surface; a tapered portion; and a main body portion, the gear portion is formed on the main body portion and the tapered portion such that a bottom land of the gear portion is positioned at radially outer side of a line extending in parallel with a rotation center axis of the worm shaft and passing through a boundary between the wall surface and the tapered portion.

Abstract: One aspect of the present invention provides a method for manufacturing a strain wave gear device. The method includes steps of measuring a between pin diameter of an internal gear, measuring an over pin diameter of an external gear, where the external gear is to be placed radially inside the internal gear, configured to mesh with the internal gear, and flexible, measuring a dimension of a bearing, where the bearing is to be placed radially inside the external gear, and flexible, and machining an elliptical cam, where the elliptical cam is to be placed radially inside the bearing, and configured to flex the external gear in a non-circular manner. The elliptical cam is machined based on the measured dimensions of the internal gear, external gear and bearing such that the internal and external gears mesh with each other at a constant position.

Abstract: A work vehicle includes a chassis defining a longitudinal axis, a prime mover configured to move the chassis in the direction of the longitudinal axis, and a steering assembly configured to pivot a wheel relative to the chassis. The steering assembly includes a knuckle coupled to the wheel, a tie rod coupled to the knuckle and having a ball portion, a steering cylinder, and a joint assembly. The steering cylinder is slidably coupled to the chassis and configured to translate relative to the chassis along a cylinder axis perpendicular to the longitudinal axis. The steering cylinder includes a connection portion having an inner circumferential surface that partially defines a bearing pocket. The joint assembly couples the ball portion to the connection portion and includes a bearing race that is received into the bearing pocket in direct contact with the inner circumferential surface. The bearing race receives the ball portion.

Abstract: A variable-tooth-thickness worm-type tool comprises a main body and a spiral blade distributed on the main body and featuring variable tooth thickness. The main body and the spiral blade are respectively described with a rack cutter coordinate system and a tool coordinate system. The vector parameters based on the rack cutter coordinate system are transformed into vector parameters based on the tool coordinate system so as to simulate the main body with a rack cutter and develop the spiral blade to have variable tooth thickness. Thus, when a gear blank is tooled, the distance between the centers of the tool holder and the workpiece holder can be set as a constant, and the feed in the radial degree-of-freedom can be neglected, with twists of tooth flanks being inhibited.

Abstract: A gear machining apparatus includes a skiving mechanism positioning a work to be machined and a pinion type cutter on axes skewing from each other, the skiving mechanism rotating the work at a predetermined position and feeding the cutter while rotating in a direction of a tooth trace of a gear to be formed at the work synchronously to the rotation of the work for producing the gear from the work. The cutter includes a tooth surface which is formed with an involute region having an involute curve in an area including a pitch circle in a tooth depth direction, an addendum region continuously formed from the involute region to an addendum, and a dedendum region continuously formed from the involute region to a dedendum the addendum region and the dedendum region being shaped in a configuration different from the involute region.

Abstract: A working apparatus, provided with a base stage, work hold and rotation device for holding and rotating a work, working device movable toward and away from the work via slider mechanism and having a working tool, press structure for pressing the working tool toward the work via the working device, and trace device pressed toward the work together with the working tool by the press structure and in contact with the work and moving the working device as a whole in forward and rearward directions according to outer shape of the work. By pressing of the pressing structure, the working tool deburrs and chamfers under control of working volume by the trace device. The work hold and rotation device has work rotation axis angle adjustment mechanism, for adjusting angle of rotation axis of the work by holding the work. The working apparatus can precisely deburr and chamfer complicated shape of work such as worm gear.

Abstract: A method for cutting worm and worm wheel in a worm-gear reduction unit (1) with circulation of bearing balls, comprising the steps of: (a) obtaining races (30) for the bearing balls (4) onto the worm wheel (3); and (b) obtaining races (20) for the bearing balls (4) onto the worm (2), wherein step (b) provides the cutting of the races (20) according to a cutting profile substantially corresponding to the envelope of the subsequent positions assumed by the bearing balls within the worm wheel races being formed.

Abstract: The present invention provides a five-simultaneously-working axis computerized numerical controlling system tooth cutting machine tool for toroidal worms, comprising two parts a body of the machine tool and a controlling cabinet. The body comprises a bed, a spindle box with a spindle, a longitudinal sliding table, a traverse slider, a vertical guideway mounted on the slider and a tailstock, a cutter rest that supports a rotating cutter head is mounted on the vertical guideway. The spindle rotates about A-axis thereof, the table longitudinally slides along Y-axis relative to the bed, the cutter head rotates about B-axis thereof and transversely shifts X-axis as well as the cutter head makes up or down shift along Z-axis of the vertical guideway.

Abstract: A forming method for milling teeth of variable tooth worms (VTW) with the following features: on a multi-axis simultaneously-working CNC machine-tool a moving coordinate system {?1(?1)[O1;{right arrow over (i)}1(?1),{right arrow over (j)}1(?1),{right arrow over (k)}1 (?1)]} is correlated to the worm blank of the VTW worms, whereon the worm blank of the VTW worms rotates around {right arrow over (k)}1(?1)-axis at angular speed |{right arrow over (?)}1|; another moving coordinate system {?2(?2)[O2; {right arrow over (i)}2(?2), {right arrow over (j)}2(?2), {right arrow over (k)}2(?2)]} is correlated to the milling cutter, whereon the milling-cutter rotates around {right arrow over (k)}2(?2)-axis at angular speed |{right arrow over (?)}2|, |{right arrow over (?)}1|/|{right arrow over (?)}2|=i12 and i12 is a constant; the feed motion of the milling cutter comprises the radial shift along {right arrow over (i)}2(o2)-axis and the peripheral shift around {right arrow over (k)}2(?2)-axis; the equations of the cutting

Abstract: Enveloping worm threads with less than one revolution have on one side concave surface and on another side convex surface. This makes generation of concave and convex enveloping worm surfaces simultaneously and makes modification of surfaces by individual machining of each surface. Proposed method uses cutting edges that have rotation radius according with radius of curvature of machining surface. Another variation simultaneously cuts several threads, where enveloping worm blank has rotation around its own axis of rotation and relative motion to helical cutter around tooling axis. This reduces production cost and makes manufacturing easily.

Abstract: A milling tool includes a milling body and a plurality of cutting inserts. The milling body has fastening devices to hold the cutting inserts in a plurality of respective insert pockets each having at least one base surface. Each of the cutting inserts has at least one cutting edge. The tool has a rotational axis and a rotational direction, as well as a feed direction and an end surface. The milling tool is provided to cut a work piece substantially in an axial direction of the tool, which is substantially perpendicular to the feed direction.

Abstract: A forming method for milling teeth of variable tooth worms (VTW) with the following features: on a multi-axis simultaneously-working CNC machine-tool a moving coordinate system {&sgr;1(&phgr;1)[O1;{right arrow over (i)}1 (&phgr;1),{right arrow over (j)}1 (&phgr;1),{right arrow over (k)}1 (&phgr;1)]} is correlated to the worm blank of the VTW worms, whereon the worm blank of the VTW worms rotates around {right arrow over (k)}1(&phgr;1)-axis at angular speed |{right arrow over (&ohgr;)}1|; another moving coordinate system {&sgr;2(&phgr;2)[O2; {right arrow over (i)}2 (&phgr;2), {right arrow over (j)}2(&phgr;2), {right arrow over (k)}2(&phgr;2)]} is correlated to the milling cutter, whereon the milling-cutter rotates around {right arrow over (k)}2(&phgr;2)-axis at angular speed |{right arrow over (&ohgr;)}2|, |{right arrow over (&ohgr;)}1|/|{right arrow over (&ohgr;)}2|=i12 and i12 is a constant; the feed motion

Abstract: A method of forming milled tooth of variable tooth worm (VTW),comprising: coupling a workpiece of worm with a coordinate system {&sgr;1(&phgr;1)[O1; {overscore (i)}1(&phgr;1), {overscore (j)}1(&phgr;1), {overscore (k)}1(&phgr;1)]} on the CNC multi-axes simultaneously coupled machine tool, in which the workpiece of worm is rotated with the angular speed &ohgr;1 around the axis of {overscore (k)}1(&phgr;1); coupling a milling-cutter with another coordinate system {&sgr;2(&phgr;2)[O2; {overscore (i)}2(&phgr;2), {overscore (j)}2(&phgr;2), {overscore (k)}2(&phgr;2)]} on the CNC multi-axes simultaneously coupled machine tool, in which the milling-cutter is rotated with angular speed &ohgr;2 around the axis of {overscore (k)}2(&phgr;2), and &ohgr;1/&ohgr;2=i and i is constant; feeding the milling-cutter to move along {overscore (i)}2(O2) axis in the radial direction and simultaneously rotate around {overscore (k)}2(&phgr;2) in the circumference direction, the coordinate

Abstract: In the production of a crown wheel which can mesh with a cylindrical pinion if the axes of rotation of the crown wheel and the pinion are not parallel, the workpiece from which the crown wheel is produced and a generating tool rotate at a ratio in the speed of rotation which corresponds to the proportion of the number of passes of the tool and the number of teeth of the crown wheel to be produced, and the tool is brought into engagement with the workpiece and is moved in such a way along the workpiece in a direction parallel to the axis of rotation of the cylindrical pinion that the tool works the tooth flanks of the crown wheel to be produced. When the center point of the tool is moved in a direction parallel to the axis of rotation of the cylindrical pinion which can mesh with the workpiece, and the teeth of which form an angle .beta.

Abstract: A base member such as an elevation pipe of a photographic tripod is severed and rack teeth are formed thereon in a single operation while the base member remains clamped in a V-block. The first rack tooth on each side of the location where the base member is severed includes half of a trough portion between adjacent rack teeth. Additional trough portions forming the remainder of the teeth are formed, either in the same severing and shaping operation, or in a later shaping operation. The formation of the inner half trough portions ensures that, when the two severed ends of the base member are brought together, a smooth transition will exist between the two rack portions. In addition, since the two severed ends always include half troughs immediately adjacent thereto, weaknesses and chipping resulting from the presence of partial rack teeth in these locations is avoided.

Abstract: There is disclosed a globoid worm gear generating method in which the surface of a globoid worm generating tool is defined as the tooth surface of an intermediate gear by an inverted conical surface whose semivertical angle .gamma. is 90.degree.<.gamma.<180.degree., a relational movement similar to that of a globoid worm wheel is given to the tool so as to generate a globoid worm, and the worm wheel is generated by a wheel generating tool having a contour wholly or partially similar to that of the globoid worm, or in which the surfaces of a globoid worm generating tool are defined wholly or partially by two inverted conical surfaces whose semivertical angles .gamma. are 90.degree.<.gamma.<180.degree., and the major axes as well as bottoms of the two inverted conical surfaces are coincident with each other so that both tooth surfaces of a worm may be simultaneously generated. By this method of the invention, the globoid worm gears can be generated within a short period of time.

Abstract: A method and apparatus for making a globoid screw for use as a mainrotor in a compressor or expander wherein a cylindrical rotor body is mounted for rotation about the longitudinal axis thereof, a cutter having a plurality of teeth at spaced locations around a circumference disposed in a plane and having an axis of rotation disposed perpendicular to that plane is mounted for rotation about its axis and is disposed so that the plane thereof is parallel to the rotor body longitudinal axis and so that the cutter rotational axis is perpendicular to the rotor longitudinal axis, and the rotor body and the cutter are rotated at synchronized speeds.

Abstract: A worm speed reducer consisting of a worm made of a relatively hard material such as cast iron or steel and a worm wheel made of a relatively hard material such as cast iron. A material strength is set so that an amount of wear of the worm becomes larger than that of the worm wheel. A tooth surface of the worm wheel is formed with a network irregularity extending in both a direction of a cutting scratch due to cutting and a direction intersecting the direction of the cutting scratch, and also formed with a chemical conversion coating having a thickness smaller than a height of the irregularity. A tooth surface of the worm is formed with a network irregularity extending in both a direction of a cutting scratch due to cutting (or a grinding scratch due to grinding) and a direction intersecting the direction of the cutting scratch (or the grinding scratch) of the worm, and also formed with a chemical conversion coating having a thickness smaller than a height of the irregularity of the worm.

Abstract: Method and device for grooving an hourglass screw wherein a tool shaft having an axis transverse to the screw blank has a tool movable selectively stepwise relative to the shaft when the tool is not engaged with the screw blank and locking means fix the tool when engaged with the screw blank for the grooving operation.

Abstract: A method and apparatus for making a globoid screw for use as a mainrotor in a compressor or expander wherein a cylindrical rotor body is mounted for rotation about the longitudinal axis thereof, a cutter having a pluality of teeth at spaced locations around a circumference disposed in a plane and having an axis of rotation disposed perpendicular to that plane is mounted for rotation about its axis and is disposed so that the plane thereof is parallel to the rotor body longitudinal axis and so that the cutter rotational axis is perpendicular to the rotor longitudinal axis, and the rotor body and the cutter are rotated at synchronized speeds.

Abstract: The present invention relates to a speed reduction apparatus for globoid worm gears. The speed reduction ratio of the engaged worm globoid worm gear and worm wheel is defined as the ratio of the rate of rotation of the globoid worm gear about its axis to the rate of rotation of the worm wheel about its axis. The structure of the present invention speed reduction apparatus is defined by the distance between the axes of rotation of the worm wheel and globoid worm gear and the spacial and speed relationships between the globoid worm gear and the surfaces of the cutting tool employed to generate the worm gear.

Abstract: A rack and pinion gear having helical teeth. A conical hob is employed for cutting recessed rack teeth in the work piece by continuously engaging the hob and work piece as the work piece moves longitudinally beneath (or with respect to) the rotating hob. To mate with the helical teeth in the rack, a helical gear having rounded or arcuate teeth is provided.

Abstract: A method and apparatus are disclosed for machining hourglass screw threads on an enveloping-type worm screw by engaging at least one angularly positioned cutter with a screw blank having an hourglass shape. The screw blank is rotated about its central longitudinal axis at the same time that each angularly positioned cutter is pivoted through the screw blank at a rate which is less than the rate of rotation of the screw blank.

Abstract: This invention pertains to a rack and pinion type steering gear for an automobile and a method for cutting rack teeth in the gear. The gear comprises a housing, a pinion rotatably supported within the housing and operatively connected to a steering wheel and a rack bar supported within the housing for slidable movement in the axial direction and rotation and provided with rack teeth in engagement with the pinion. The rack teeth are formed on the rack and along a varying pitch line so that the axial movement amount of the rack varies as the pinion rotates.

Abstract: A tool having only an end cutting-edge carries out a first movement of penetration into a screw blank so as to produce a groove having flanks substantially parallel to the pinion axis. The tool-holder is angularly displaced with respect to the spindle which carries the screw blank. A second movement of tool penetration takes place while the relative displacement is progressively reduced in order to obtain an inclined flank which produces a V-shaped profile. The screw is intended to form part of a compression and expansion machine and to cooperate with at least one pinion having V-form teeth.