Abstract: Gear cutting is to be effected in high efficiency and at low cost. To this end, using a hob 16 coated with at least one layer of a film of a composition comprising:(Ti.sub.(1-x) Al.sub.x)(N.sub.y C.sub.(1-y))0.2.ltoreq.x.ltoreq.0.850.25.ltoreq.y.ltoreq.1.0,dry cutting is performed at a cutting speed in the range of 80 to 400 m/min without using a cutting oil. Teeth can be generated at a greatly improved cutting speed without using any expensive tool such as a tool made of cemented carbide.

Abstract: A gear shaper effects a gear shaper cutting method by dry cutting, using a pinion cutter made of high-speed tool steel at a high efficiency. The pinion cutter of the gear shaper is coated, at least on the flank thereof, with at least one layer of film having a composition comprising: (Ti.sub.(1-x) Al.sub.x)(N.sub.y C.sub.(1-y) ), wherein 0.2.ltoreq.x.ltoreq.0.9 and 0.2.ltoreq.y.ltoreq.1.0. Gear shaper cutting is performed at a cutting speed of 300 m/min or less.

Abstract: A compact high through-put gear cutting machine collects stress transmitting structure adjacent to the work piece significantly reducing the weight and cost of the machine while providing a high degree of rigidity. This structure is positioned so as not to collect hot metal chips resulting from the cutting process which are cleared through an opening in the structure to a tubular frame isolated in stress and heat from the stress structure. DC synchronous servo motors drive five of the axis slaved to the cutter axis which is an AC induction motor driven by a vector drive. A lightweight tubular frame replaces a cast iron frame traditional in such machines. A compact axis structure is obtained by eliminating a y-axis or cutter feed motor and synthesizing that motion through a relatively shallow z, y axis table.

Abstract: The profiling tool (10) has a segment (12) of a worm thread. Its active zone (13) is coated with grains of hard material (16) and is crowned in cylinder sections coaxial to the tool axis (26). During profiling, the grinding spindle (2) and the tool (10) rotate synchronously. By appropriate correction of the coupling ratio by means of a CNC control when moving the tool (10) in axial direction of the grinding worm (2), the grinding worm flank (1) can be dressed with any desired topology. The method makes it possible to profile topologically modified grinding worms (2) at the grinding worm (2) rotational speed used for grinding, which was previously not possible.

Abstract: In order to rotationally drive a gear material (3) when the gear material (3) is gear machined using a hob (not shown), a drive hole (34) having a circular configuration in section and extending on an axis L of the gear material (3) is formed in an end face (3e) of the gear material (3) and a shaft member (4) having a polygonal configuration is employed. The distance from an axis of this shaft body (4) to each angular portion (4a) is larger than the radius of the drive hole (34). The distance from the axis of the shaft member (4) to each side portion (4b) of the shaft member (4) is smaller than the radius of the drive hole (34). The shaft member (4) is fitted, under pressure, in the drive hole (34) and the gear member (3) is rotationally driven through this shaft member (4).

Abstract: Method of producing a conical or cup-shaped crown wheel which can mesh with a cylindrical pinion with the inclusion of an angle .alpha.. The crown wheel is produced by means of a generating process. The tool (1, 43) consists of a disc (3) which has machining elements (53) disposed on its circumference whose cutting edges lie in the surface of a profile which extends in the form of helical ribs (4) at a pitch angle .gamma. around the circumference of the disc (3), said profile in each cross-sectional plane perpendicular to the helical direction of the ribs (4) being the shape of a number of adjacent cuttting teeth (53), based on the basic geometry of a cylindrical pinion which is characteristic of the crown wheel and the center point of which lies on a circle which is in a plane perpendicular to the rotation shaft of the tool, and has a center point lying on the rotation shaft of the tool.

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 method for the precision machining of flanks of gear-wheel-shaped workpieces, in particular those with convex teeth, using an internally toothed tool with crossed axes, in which simultaneous relative movements take place not only in three mutually perpendicular axes but also around an axis perpendicular to the cross-axes angle such that not only the tooth flanks of the tool and the workpiece have tangential contact with one another but also the base body of the tool and of the workpiece touch one another at a point of contact IV of which the position changes continuously, and a straight line g orthogonally penetrating the base body of the tool and the base body of the workpiece at the point of contact not only intersects the axis C.sub.1 of the workpiece or of its base body and the axis C.sub.2 of the tool or its base body (points III, II), but also passes through the center I of an ideal sphere K.sub.1 which adapts itself to the base body of the workpiece at the point of contact IV.

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 wobblestick and a method for forming teeth on a wobblestick wherein the minimum distance between the axis of the hob and the axis of the wobblestick remain substantially uniform throughout the forming of the teeth so as to form the teeth while producing a wobblestick having a uniform diameter throughout the length of the wobblestick.

Abstract: A wobblestick for forming teeth on a wobblestick wherein the minimum distance between the axis of the hob and the axis of the wobblestick remain substantially uniform throughout the forming of the teeth so as to form the teeth while producing a wobblestick having a uniform diameter throughout the length of the wobblestick.

Abstract: Disclosed herein is a hobbing machine particularly for the production of spur and helical gears. The hobbing machine is characterized in that a separate mechanism for hob shifting is not required. The hob shifting, as well as other machine motions, is carried out by linear movement of the tool and workpiece relative to one another in up to three mutually perpendicular directions. The machine also includes tool support means to which the hobbing tool is mounted and which is rotatably adjustable for controlling the angular orientation of the hobbing tool. A control system including a computer controls the linear movements, angularly adjustable tool support movements, as well as the necessary timed rotations of the tool and workpiece.

Abstract: A method of modified gear cutting of a globoid worm gear. A worm wheel gear cutting tool employs a conical cutting surface which is substantially the same as the conical surfaces of the teeth of a cooperating globoid worm wheel. The worm wheel is the reciprocal image of the conical cutting surface of the tool. A worm gear is cut by imparting to the cutting tool a motion defined both by the distance between the axis of the worm gear to be cut and the axis of rotation of the cutting tool as well as the speed reduction ratio which constitutes the ratio of the speed of rotation of the cutting tool to the speed of rotation of the worm gear.

Abstract: A method for simultaneously cutting and chamfering involute gears. The pressure angle .alpha..sub.1 and module M of the teeth of a hob for cutting the teeth are selected with respect to the nominal pressure angle .alpha..sub.0 and nominal module m of the gear to be cut according to the following equation: m cos .alpha..sub.0 =M cos .alpha..sub.1. According to the present invention, a single hob cutter is sufficient to cut gears having a wide range of numbers of teeth.

Abstract: A gear hub for flexible gear couplings wherein the teeth of said hub are cut while the hub is being moved constantly through all of the positions that the hub would assume relative to the sleeve during operation with the hub shaft misaligned with the sleeve at the maximum angle of misalignment for which the coupling is designed.

Abstract: An hourglass worm wheel and method of hobbing same wherein the finished worm wheel (70) includes a mid zone (B) where the root surface and outside helix are cylindrical for a predetermined distance along the axis of the worm wheel. The method forming the mid zone includes a combination radial and axial feeding of a hobbing tool (58) rotating in synchronization with the rotating worm wheel blank (50).

Abstract: A method and apparatus for determining the angular position of a workpiece and for positioning the same relative to at least one tool. The workpiece has at least one set of teeth. Pulses are derived from a rotating reference workpiece and from a reference shaft which has a known gear ratio with the reference workpiece, and consequently also turns. A first phase measurement is undertaken between the pulses, the result of which is stored as the reference value. The reference workpiece is replaced with a workpiece which is to be machined and which is provided with teeth. A second phase measurement between the pulses of the refernece shaft and of the reference workpiece are undertaken in a second measuring operation. The reference value of the first phase meaasurement is compared with the result of the second phase measurement. The workpiece is turned relative to the reference shaft in conformity with the difference between the two measured values.

Abstract: A method of manufacturing hubs for flexible gear couplings is disclosed wherein the teeth of said hub are cut while the hub is being moved constantly through the position that the hub would assume relative to the sleeve during operation with the hub shaft misaligned with the sleeve at the maximum angle of misalignment for which the coupling is designed.

Abstract: The method is used for machining flanks of unhardened or hardened, spur-toothed or helical-toothed, internally toothed or externally toothed cylindrical gears by skiving. Basic rotation is produced between a tool and a workpiece. In addition, a helical motion between the tool and the workpiece is produced. The relative motion between the tool and the workpiece is executed with high accuracy, and any variations in the relative motion are corrected. The tooth number z.sub.0 of the tool, for minimizing the effect of the variations of the tool and its mounting, is fixed in such a way that, in the case of z.sub.0 .gtoreq.z.sub.2 (z.sub.2 is the tooth number of the workpiece, z.sub.0 is the tooth number of the skiving tool), the ratio i=z.sub.0 /z.sub.2, and in the case of z.sub.0 >z.sub.2, the reciprocal of the ratio 1/i=z.sub.2 /z.sub.0, result in an integral value or the ratio of two integral numbers, the amount of which is as small as possible.

Abstract: For the precision working of particularly hardened bevel gears, a method and an apparatus are disclosed in which the workpiece is moved during rolling contact with a bevel-gear-shaped tool having abrasive flanks. Workpiece and tool rotates in meshing relation with their axis spaced and crossed and each connected with a guide gear which also meshing engage and roll with one another. Both the workpiece-tool pair and also the guide-gear pair run each with backlash, however, on opposite flanks, so that the entire combination runs without backlash.

Abstract: A method is disclosed which envisages the use of a vertical axis equipment magazine with a number of stations, each occupied by a workholding device, and a change arm that is rotatable through a horizontal plane and which picks up devices singly from the magazine and transfers them to a work rest. The work rest itself is provided with a flat horizontal surface and a vertical cylindrical surface serving to support and locate the device, respectively, and a scraper is employed for the purpose of keeping these surfaces clean. A sensor detects any error in the position of the workholding device relative to the two surfaces.

Abstract: A process for controlling the tool infeed prior to machining a semi-machined gear comprises aligning the tool with the gear and feeding the tool radially inwardly in rapid traverse without making contact with the gear. The continuous rotating tool is then fed in incrementally in intervals of at least one gear revolution until the tool touches the gear for the first time. At this time the machining process is started.

Abstract: The method is used for measuring and/or controlling the position of a rotating reference element of a machine tool as a function of the position of a rotating main guide element. The two elements execute a basic movement with a transmission ratio which is constant in the ideal case. From the elements executing the basic movements pulse sequences are derived and their frequencies are made equal. The reference element executes an additional movement which, compared with the basic movement, occurs slowly and is predetermined as a function of the position of another moving element. To superimpose the additional movement, at least one of the signals describing the basic movement is shifted in phase relative to the reference element and a phase comparison is executed between the signals obtained, in such a manner that the resolution of the phase shift is distinctly finer than the distance between adjacent pulses of the signals derived from the main guide element and from the reference element.

Abstract: For the precision working of particularly hardened bevel gears, a method and an apparatus are disclosed in which the workpiece is moved during rolling contact with a bevel-gear-shaped tool having abrasive flanks. Workpiece and tool rotate in meshing relation with their axis spaced and crossed and each connected with a guide gear which also meshing engage and roll with one another. Both the workpiece-tool pair and also the guide-gear pair run each with backlash, however, on opposite flanks, so that the entire combination runs without backlash.

Abstract: A method and apparatus for determining the angular position of a workpiece and for positioning the same relative to at least one tool. The workpiece has at least one set of teeth. In a first measuring operation, a measuring wheel having a tooth construction is made to mesh with a set of teeth of a reference workpiece. Pulses are derived from the rotating measuring wheel and from a reference shaft which has a known gear ratio with the measuring wheel, and consequently also turns. A first phase measurement is undertaken between the pulses, the result of which is stored as the reference value. The reference workpiece is replaced with a workpiece which is to be machined and which is provided with teeth. A second phase measurement between the pulses of the reference shaft and of the measuring wheel are undertaken in a second measuring operation. The reference value of the first phase measurement is compared with the result of the second phase measurement.

Abstract: Gear teeth of the gear being worked are machined by rotating the gear with a gear-type machining tool moved radially into tangential contact with the gear being worked. The relative of rotation rates of the gear and the tool are determined by the number of gear teeth in both the gear and the tool. The tooth width of the gear-type machining tool, which may be a worm gear, is less than the finished measurement of the tooth space of the gear being worked. When the gear-type tool reaches the prescribed manufacturing center distance, it is contiguous with the gear from one frontal face to the other. Two flanks of the gear are machined by feeding either the gear or tool in a direction perpendicular to the radial direction of movement so that the teeth of the tool can machine the gear tooth flanks as the gear and the tool rotate. First one flank of each tooth of the gear may be machined and then, by reversing the movement direction, the other flank of the tooth is machined.

Abstract: A synchronous operation control apparatus for rotating a grinding wheel and a gear to be ground thereby in synchronism to grind teeth of the gear to a nicety. A pulse generator is connected to a rotational drive source for rotating the grinding wheel, and a counter is connected to an output terminal of the pulse generator. A division error is calculated from the number of teeth of the grinding wheel and the number of teeth of the gear which have been supplied in advance, to produce data for correcting the division error. A rotational drive source for rotating the gear is energized by frequency-divided pulses issued from the counter with a count as corrected by the data.

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: In a process for machining a spur gear by using a grinding worm having a curved tooth thickness smaller than the final measurement of the curved tooth gap of the spur gear to be produced, the grinding worm is first directed radially towards the spur gear until the desired distance between the axes is reached. Subsequently, a relative circular feed movement is carried out consisting of a positive or negative additional rotating movement of the gear or the worm. This additional rotating movement is superimposed on the corresponding basic revolution of the gear or the worm. In this way, first one flank and subsequently the other flank of each gear tooth is machined to its final dimension. With this process, a full linear contact exists between the grinding worm and the tooth flank of the gear during roughing independent of the amount of material to be machined. Due to the existing play, an effective cooling is possible so that high grinding outputs can be achieved.

Abstract: A method of manufacturing large gears by performing all steps required on a single vertical boring mill without removing the gear blank from the rotary table of the mill.

Abstract: Tooth flanks of a gear are produced with a cutter head rotating about a cutter head axis and equipped with cutters having internal or inner cutting edges and external or outer cutting edges. In order to obtain a further increase in the gear cutting capacity or output, while avoiding the therewith usually associated tooth flank errors, the cutter head axis is pivoted out of a normal within or into a plane, as the case may be. At the cutter head the external cutting edges are arranged at a first circle, the internal cutting edges at a second circle and such respective cutting edges are arranged in offset relationship from a uniform angle division or pitch through a predetermined respective angle. The external cutting edges and the internal cutting edges form with a normal to a tangential plane a respective predetermined angle.

Abstract: A double helical gear set having a pair of driving pinions meshed with a pair of driven gears, respectively, is aligned by providing accurately aligned integral or demountable pinions on one shaft and aligning the driven gears using a fixture which is operable to locate a keyway or other aligning device on each of the driven gears so that the driven gears can be timed or aligned on their support shaft. The fixture has a hub member which fits in the bore of the gear hub and includes a locating pin engageable with opposed flanks of adjacent teeth at corresponding points on the tooth profile such as the pitch point. The fixture includes interchangeable locating pin support members for use in aligning helical gears having different diametral pitches and helix angles.

Abstract: The hobbing machine is of simplified construction and is dedicated essentially to forming only a single type of gear or a narrow range of gears. To enable the machine to be of simplified construction, its drive train consists of only four gears and its hob head is mounted to pivot around the axis of the drive shaft for the work spindle. The arrangement of the four gears together with the pivotal movement of the hob head enables the hob spindle to be inclined at a predetermined setting angle relative to the work spindle and enables the center distance between the spindles to be selectively changed.

Abstract: A process for dressing a single or multiple-grooved worm or threaded workpiece by a single or multiple-grooved worm or threaded dressing tool includes the turning of the workpiece and tool with the dressing tool in a comb-type contact with the workpiece. By using an additional axial relative movement between the dressing tool and the workpiece, determined by the radial positioning and return movements, the contact points are displaced such that the desired grinding profile is produced on the workpiece. Since the entire surface area of the instantaneous contact points is significantly smaller than the entire profile area of the workpiece, the cutting forces which occur are relatively small, so that high dressing speeds can be obtained. It is also possible to make various flank corrections on the workpiece. The apparatus for carrying out the process is also disclosed.

Abstract: A method for generating a shape on the periphery of a non-rotating workpiece by orbiting a rotating hob in cutting engagement with the workpiece while moving the hob and workpiece relatively lengthwise of the workpiece.

Abstract: A method and control system for gear cutting machines such as hobbing equipment, shaper cutters and bevel-cutting equipment for achieving greater accuracy, productivity, and gears of increased quality while eliminating error, tedious calculations, labor and product variation is provided by employing a control system and utilizing a method of hobbing wherein optimum hob cutter efficiency is maintained by electronically monitoring and controlling hob input power, hob shift and workpiece feed to produce gears approaching the optimum theoretical calculated configuration. The method of cutting gears and the control system provides for the production of more accurate gears by eliminating the use of cams in shaper cutters and the use of change gears in hobbing machines and by properly controlling hob shift to result in an increased hob cutter life and provide higher production of optimally designed gears.

Abstract: A method and apparatus for effecting an automated exchange of a tool in hobbing machines. At least a pair of gripping devices are mounted on a shaft for relative sliding movement therealong and for selective locking engagement with the shaft so that a rotation of the shaft will effect a rotary movement of a selected one of the gripping devices. The rotary movement of the selected gripping device is between a storage position and a working position. The gripping device is capable of holding a tool which is to be exchanged for a worn out tool. The other gripping device is generally empty and is first moved into the working position to extract the worn out tool from the milling spindle. Thereafter, the gripping devices are shifted to bring the appropriate device having a new tool therein into a position so that it can be rotated with the shaft to bring the new tool into the working position and inserted onto the milling spindle.

Abstract: This invention concerns a method for the synchronization of a gear machining instrument that works according to the hobbing method. It has different drives for the tool and the work-piece. In the process, a series of pulses are produced, dependent upon the rotational speed of each drive. The occurrence of the pulses are compared digitally resulting in an analog control signal for the adjustment of the work-piece drive.

Abstract: An improvement of a globoid worm gear generating method based on the "basic member gear theory" and the "secondary action theory" both proposed by the same inventors is disclosed. In one form, the surface of a globoid worm generating tool is defined as the tooth surface of an intermediate gear by a conical surface whose semivertical angle .UPSILON., 0.degree..ltoreq..UPSILON..ltoreq.90.degree.. In another form, the surfaces of a globoid worm gear generating tool are defined by two conical surfaces whose semivertical angles are equal and satisfy the above condition and whose major axes as well as bottoms are coincident with each other so that both tooth surfaces of a worm may be simultaneously generated.

Abstract: The present invention relates to a method and apparatus for the production of an additional rotational motion of a helically toothed gear workpiece in an electronically, positively controlled gear processing machine operating according to the hobbing method which has separate rotating drives for workpiece and tool. In this process, a series of impulses are supplied to a controller. These impulses are compared to each other for the production of a control signal for the readjustment of the workpiece drive. The series of impulses are dependent upon the rate of rotation of each of the drives. An additional signal is supplied which is derived from the longitudinal advance of the workpiece in relation to the tool.