Abstract: Method for machining right toothed bevel gears, wherein:

Abstract: A machine for manufacturing bevel and hypoid gears comprising a machine column including a first side and a second side. A first spindle is movably secured to the first side with the first spindle being rotatable about a first axis. A second spindle is movably secured to the second side with the second spindle being rotatable about a second axis. The first and second spindles are movable linearly with respect to one another in up to three linear directions with at least one of the first and second spindles being angularly movable with respect to its respective side. The angular movement of at least one of the first and second spindles being about a respective pivot axis extending generally parallel with its respective side.

Abstract: A mechanical gear hob is equipped with an automatic stock divide device that enables the hob to cut or re-cut gear parts that already have teeth in them by automatically synchronizing the gear teeth to the hob cutter. The hob is equipped with a hob shift position sensor and a hob cutter rotary position sensor to input to a controller the lateral and rotary positions of the hob cutter. A stock divide sensor is mounted adjacent the worktable to determine the location of the gear teeth previously formed in the workpiece. A servomotor is mounted to the differential input shaft in the hob drive train and has a rotary position feedback to the controller as well. Stock divide is accomplished by an input to the differential, causing the workpiece to rotate relative to the hob cutter to bring the existing teeth on the workpiece into phase with the teeth of the hob cutter.

Abstract: A method for manufacturing a variable-diameter gear pair operable with a conjugate action therebetween includes the steps of providing a first workpiece and a second workpiece, each having a minor and a major diameter portion in spaced relation therefrom along a longitudinal axis. At least one gear tooth is formed within the first (second) workpiece for forming at least one first (second) gear body, wherein the at least one gear tooth within the first (second) at least one gear body curves outwardly in a radial and axial direction from the longitudinal axis, and wherein each of the at least one gear tooths includes a width dimension that changes in size between the minor and major diameter portions. Each of the first and second at least one gear bodies has the variable diameter and variable pitch for forming a gear pair operable with each other with a conjugate action therebetween.

Abstract: A bevel gear is generated using an annular milling cutter having a blade material made of a high-speed tool steel mounted to a main body, the blade material being coated with at least one layer of a film of a composition substantially comprising (Ti(1−x)Alx)(NyC(1−y)) (where, 0.2≦x≦0.85, 0.2≦y≦1.0), and dry cutting is performed at a cutting speed in the range from 20 to 400m/min without using a cutting oil. With this method, teeth can be generated at a greatly improved cutting speed without using any expensive tool such as cemented carbide, thereby realizing efficient production of a bevel gear at a reduced cost.

Abstract: A process and a machine for fine machining of the tooth flanks of geared workpieces with a driven tool in the form of a gear wheel or worm gear which is in meshing contact with a workpiece, the axes of tool and workpiece intersecting. During machining of the workpiece the tool is driven in a direction of rotation which remains the same and adjustable torque values are applied to the workpiece in one direction and subsequently in the opposite direction.

Abstract: This invention is directed to a method of using a two spindle Hurth-Module multi-spindle (or similar) cutting machine to accomplish face hobbing of hypoid and spiral bevel gear sets. A first cutter mounted on a first spindle would rough cut the gears and a second cutter mounted on a second spindle would finish the gears with both cutters using a face hobbing process. According to this process, multiple cutters are used for a single gear, but on a single machine, thereby reducing cutter wear, increasing cutter life, and raising production output of the multi-spindle machine by utilizing both spindles. In one embodiment, a fine pitch cutter is used to create the initial rough-cut of the gear, and a second coarse pitch cutter is used to create the finish cut of the gear.

Abstract: A method for manufacturing a variable-diameter gear pair operable with a conjugate action therebetween includes the steps of providing a first workpiece and a second workpiece, each having a minor and a major diameter portion in spaced relation therefrom along a longitudinal axis. At least one gear tooth is formed within the first (second) workpiece for forming at least one first (second) gear body, wherein the at least one gear tooth within the first (second) at least one gear body curves outwardly in a radial and axial direction from the longitudinal axis, and wherein each of the at least one gear tooths includes a width dimension that changes in size between the minor and major diameter portions. Each of the first and second at least one gear bodies has the variable diameter and variable pitch for forming a gear pair operable with each other with a conjugate action therebetween.

Abstract: Chip enclosure (150) wherein the interior portion comprises a primary suction port (152) and a secondary suction port (154). Both primary suction port and secondary suction port are connected via a short neck portion (155) to outlet (156) that is in communication with a source of vacuum. The bulk of chips formed as a result of machining are captured by the primary suction port (152) while any remaining chips fall to the lowest location of the chip enclosure (150) where they are drawn in to the secondary suction port (154).

Abstract: Centering device acting upon an already present first ring (14a) of a straight or double helical toothing of gears, sprocket wheels or pulleys to obtain the second ring (14b) of the toothing generated by a pinion shaped cutter (16), a central groove (19) separating said first ring and said second ring. The centering device comprising a retractable pin (20, 120), cooperating during the positioning step of the gear (13), with at least a tooth (15) of the first ring (14a), having a first waiting position (20a, 120a) and a second operating position (20b, 120b) defining the angular position of the gear (13) clamped on the rotary supporting base (18), the angular position being functionally correlated to the plane which contains the axis (25) of the gear (11) and the axis (26) of the cutter (16).

Abstract: A method of gear design perfects design of gear teeth geometry (30) instead of limiting gear-tooth design to present cutter geometry and manufacturing methods. A pair of varied-diameter cutters (22, 29), such as hypoid cutters, have a geometric form that generates variable diameter toothed elements. Structures of hypoid or other varied-diameter cutters are achieved with a cutting tool (9) having a design cross-sectional shape of an idealized space between gear teeth on both of a pair of cutters. The cutter tool is rotated and reciprocated in shaping or machining relationship to other cutter blanks (18) or workpiece (10) in design rotation on cutter axes of a cutting-machine spindle (5). The cutter axes have variable heights above the cutter tool. Simultaneously with shaping or machine cutting either cutter blank, the angle of reciprocation and linear positioning of the cutter tool and height of center of the cutter axes are varied designedly.

Abstract: An apparatus and method for milling internal gears and splines using a pair of opposed milling cutters disposed internally in a gear or spline blank. The apparatus generally milling gear teeth on generally opposite sides of the blank with an indexing mechanism for manipulating the orientation of the milling apparatus with respect to the blank. Also disclosed are internal gears having milled teeth which are manufactured using the apparatus and the method.

Abstract: A method for producing a fillet on a gear as a function of a plurality of design criteria points in disclosed. The present method includes the steps of fitting a polynomial curve to the design criteria points, and producing the fillet on the gear, the fillet having a curved shape corresponding to the fitted polynomial curve. As a further step for control of the fillet, the actual shape of the fillet produced can be inspected and compared to the fitted curve, using a coordinate measuring machine or other suitable device. According to a further aspect of the invention, the fillet is produced using a tool having a curved surface corresponding to the polynomial curve.

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 method for determining front-face indexing errors of like cutting blades mounted in a face hobbing cutter head. The cutter head is rotatable about a cutter axis and the like cutting blades (e.g. inside cutting blades or outside cutting blades) each having a cutting edge and are arranged in a plurality of blade groups in the cutter head. The method comprises determining the angular position of the front face of one or more of the like cutting blades about to the cutter axis by rotating the cutting edge of one or more of the like cutting blades relative to an angular detecting means, such as a non-contacting probe. The measured front face angular positions are compared with respective theoretical front face angular positions and an angular difference, .DELTA..phi..sub.c, is calculated. A cutting blade front face index error, F.sub.d, is then calculated and this error amount may be compared to acceptable limits and the blade may be replaced of the cutter scrapped if such limits are exceeded.

Abstract: A method of machining one or more tooth slots in a bevel gear-shaped workpiece with a cup-shaped tool having one or more stock removing surfaces. The method comprises indexing the workpiece by rotation about a workpiece axis to bring one of the tooth slots to a final machining position. Simultaneously with at least a portion of the indexing, positioning the tool to contact the workpiece to commence machining the slot and infeeding the tool during the indexing while moving the tool with the indexing workpiece to maintain the tool positioned in the slot. The infeeding, movement of the tool, and indexing continuing at least until the final machining position is achieved.

Abstract: A method of feeding a tool to a predetermined depth in a workpiece in a machining process for producing at least one tooth surface on the workpiece. The workpiece being rotatable about a work axis and the tool being rotatable about a tool axis and includes at least one stock removing surface, The method comprises rotating the tool about the tool axis and contacting the rotating tool and the workpiece. The tool is fed relative to the workpiece along a feedpath to the predetermined depth wherein at least a portion of the feedpath is defined by a feed vector comprising at least first and second feed vector components. The first and second feed vector components are positioned in a plane defined by the work axis and the direction of the tool axis with the first feed vector component being substantially in the direction of the tool axis and the second feed vector component being substantially in the direction of the face width of the workpiece.

Abstract: The invention relates to a method for producing continuous corrections on a bevel gear, whereby by entering a plurality of corrections into the CNC control of the machine and interpolation between them, camber designs and even the designs of twists or the avoidance of twists on the tooth flanks can be performed by suitable superimposition of corrections on the inner and outer tooth tips with corrections of the plunger position.

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: 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: Disclosed herein is a process for feeding a tool relative to a workpiece in a machining process such as a process for forming bevel and hypoid gears. The method comprises feeding the tool from an initial contact position with the workpiece to a full depth position in the workpiece along a feedpath at least a portion of which is defined by a feed vector having at least two feed vector components lying in an axial plane. The first feed vector component being substantially in the direction of the axis of a theoretical generating gear and the second feed vector component being substantially in a direction perpendicular to the generating gear axis. The feed vector may include a third feed vector component lying in a normal plane. With this feedpath undesirable tool shifting and workpiece spiral angle changes are significantly reduced.

Abstract: At the gear manufacturing machine there are automatically fabricated longitudinally curved tooth gears, especially longitudinally curved tooth bevel and hypoid gears according to conventional stock-removal form or generating methods. In order to improve both the mechanical stability and kinematic stability, the gear manufacturing machine contains only so-to-speak "natural" gear manufacturing or cutting axes, and, in particular, does not contain any hypoid stock, however, a generating drum. With the method of operating such gear manufacturing machine it is possible to fabricate hypoid gears during the generating operation by performing an additional movement of the workpiece in the lengthwise direction of the tooth pitch cone.

Abstract: Disclosed herein is a process and apparatus for grinding tooth surfaces of spur and helical gears by a generating method. The outer tooth surfaces of a theoretical ring gear are conjugate to the grinding surfaces along the width of a generally hourglass shaped grinding wheel. The grinding wheel is rotated which in turn causes the theoretical ring gear to rotate. A work gear is rotated in mesh with the internal tooth surfaces of the theoretical ring gear and simultaneously is traveresed in mesh across the width of the grinding wheel with the center of the work gear moving in a path about the center of the theoretical ring gear.

Abstract: A method for, via skiving, finishing the flanks of the teeth of a cylinder wheel that is provided with internal or external spur or helical gearing is generated. The right and left flanks of the teeth are provided in separate operations and, to produce helix modifications, the center distance, and/or the additional rotation, of the workpiece relative to the tool are altered over the face width of the gear. During axial movement, one or at the same time several of the setting parameters center distance, offset of the tool, swivel angle, and additional rotation are automatically altered in such a way that the distortion of the flanks that would be generated at conventional skiving of crowned gears is compensated for and a tool is used for the finishing that at the right and left flanks has a cutting edge geometry that conforms to the effect on profile of the mean setting parameters that are effective during material removal by the respective cutting edge.

Abstract: Prior art non-generated, tip-relieved spiral bevel gears had tip-relieved surfaces that were nonuniform from the toe to the heel thereof. The subject tip-relieved spiral bevel gear is adapted to be manufactured by a gear generating machine, and includes a plurality of modified gear teeth individually having a convex tooth face and a relatively uniform tip-relieved surface on the convex tooth face from the toe to the heel portion thereof essentially parallel to the face angle at the outer tip surface. A two-pass method of machining the modified gear teeth is described.

Abstract: A method is disclosed wherein standard generating motions for the production of bevel and hypoid gears are modified by the substantially simultaneous inclusion of additional controlled motions which enable a desired tooth surface geometry to be produced on the gears. The additional motions comprise varying the position of intersection of the theoretical generating gear axis and the pitch plane and/or varying the orientation of the tooth surfaces of the theoretical generating gear with respect to the body of the theoretical generating gear. A CNC machine is preferably utilized for carrying out the inventive process. The inventive process is applicable to generating processes of both the face milling and face hobbing type.

Abstract: A method of forming a relief at the toe end of the teeth on a bevel gear is disclosed. The width of the blades that cut the longitudinally extending convex or concave profiles of the flanks of the teeth is increased to a dimension greater than the width of the tooth slot at the toe end whereby additional stock is removed from the toe end of the flank opposite the flank being cut by the blades. The relief is formed at the toe end of each tooth with the relief being on the same flank profile for all teeth. Lapping interference is eliminated. A separate chamfering operation is not required.

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: For manufacturing a pinion of a pair of mating bevel gears having contact-line tooth bearing or crowning in accordance with the method developed by Litvin et al, the cutter radii of respective outer and inner blade edges in the duplex or double-cut method and therewith the centers of rotation of the cutter heads as well as the center of rotation of a generating gear are altered in relation to the settings for manufacturing the mating or meshing gear. This would require cutter heads provided with adjustable cutter radii. In order to render possible the use of commercially available cutter heads, provision is made for achieving the alternation of the cutter radii by inclination of the cutter-head axes.

Abstract: A method and apparatus for finishing bevel gears has a pair of bevel gears which are rotatably engaged in a meshing fashion while being imparted with a brake force therebetween and one of the bevel gears is rocked against the other along a tooth profile direction extending between a tooth top and tooth root of a gear tooth in a manner such that the rocking bevel gear swingably rocks around its pitch apex of the base pitch cone thereof. Further, the bevel gears finish contacting gear tooth surfaces of at least one of the bevel gears both by rotational contact and by sliding contact by rocking motion.

Abstract: A computer controlled machine for forming longitudinally curved tooth bevel and hypoid gears having a minimum number of movable machine axes for setup and operation. The movable axes include three rectilinear axes (X, Y, and Z) and three rotational axes (T, W and P). The rectilinear axes are arranged in mutually orthogonal directions. Two of the rotational axes (T and W) provide for rotating tool (26, 27) and work gear (42, 43), respectively. The third rotational axis (P) provides for adjusting the relative angular orientations of tool axis (T) and work axis (W). Pivot axis (P) is positioned with respect to both tool axis (T) and work axis (W) at fixed inclination angles. A method of opeating the computer controlled machine provides for controlling the movable axis (X, Y, Z, T, W, and P) in response to setup and operating parameters of conventional bevel and hypoid gear generating machines.

Abstract: A process for the discontinuous profile grinding or milling of gear wheels with wheel-type or shank-type tools which includes setting approximate parameters for the workpiece to be worked by the tool so as to avoid large profile deviations, determining by calculation or trial the profile of the workpiece following work thereon, comparing the work profile with the predetermined profile of the finished workpiece, and resetting the parameters as necessary to correspond the actual work profile with the required profile for the workpiece.

Abstract: A process for the making and/or finishing of a crown wheel using a metal-cutting tool, the crown wheel being intended for meshing with a predetermined cylindrical gear. The metal-cutting tool is a rotary disc-type element whose working transverse section lying in the plane of the axis of rotation corresponds essentially to the tooth profile of the cylindrical gear. The disc-type element is placed in such a way relative to the crown wheel to be made that the tooth profile of the element coincides with the tooth profile of the cylindrical gear when it is engaged with the crown wheel. The disc-type element is put into a to and fro linear motion perpendicular to its axis of rotation and is at the same time tilted about an axis which coincides with the axis of rotation of the cylindrical gear when it is engaged with the crown wheel. The tooth profile of the element meshes with the crown wheel to be made and finishes the tooth flanks according to the generating principle.

Abstract: A workpiece gear to be finished is held in mesh with a gear finishing tool with substantially no backlash therebetween. The gear finishing tool is then driven in mesh with the workpiece gear, and the workpiece gear is rotated in synchronism with the driven movement of the gear finishing tool. Simultaneously, the gear finishing tool and the workpiece gear are moved reciprocally with respect to each other in the direction of a tooth trace for finishing gear surfaces of the workpiece gear. With this gear finishing method, gears can be finished highly accurately with no profile error and at an increased rate. An apparatus for carrying out the gear finishing method is of a simple construction.

Abstract: This method is for finish machining the teeth of rough machined bevel gears having longitudinally curved teeth where finish machining is undertaken subsequent to case hardening. To permit economical fabrication of such bevel gears at least in mass production, the bevel gears are ground as workpieces by a tool designed as a hypoid gear and provided with at least one abrading surface on tooth flanks of its toothing. The workpiece and the tool are brought into mesh and positively and synchronously rotarily driven in the ratio of their respective tooth numbers. Displacement of the tool axis relative to the workpiece axis as well as speeds of the tool and the workpiece are selected such that a relative sliding velocity arising between the tool and the workpiece lies within the range of conventional surface speeds for grinding. All concave tooth flanks of the workpiece or all convex tooth flanks of the workpiece or both are continuously ground in a single operation with a feed motion.

Abstract: A method for manufacturing precision gate-rotors and gate-rotor supports a single-screw mechanism by cutting the complex tooth profiles in a cylindrical gate-rotor blank. The cylindrical blank is rotated about its center axis as a cutting tool is translated in a fixed two-axis plane, one axis being the centerline of the cylindrical blank and the second axis being a line extending radially therefrom. This process may be carried out by a multi-axis, numerically controlled milling machine.

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: An apparatus for manufacturing or machining externally toothed gears using a hyperboloidally or similarly formed, internally or externally toothed tool with abrasive tooth flanks. The tool and workpiece roll on one another about respective axes which cross at a distance. The tool has a sufficient axial dimension so that it is in engagement with the workpiece teeth from one side surface to the other of the workpiece. The workpiece and tool are coupled with guide wheel pairs. Each guide wheel pair runs with potential for backlash, but the overall gearing is such that no such backlash can occur.

Abstract: A method of manufacturing bevel and hypoid gear pairs according to an imaginary mating gear cutting process. The tooth spaces are cut by means of a face-mill cutter head rotating about an axis of rotation. In order to overcome heretofore prevailing limitations on the gear diameter, cone angle and shaft angle of gear pairs, either the gear or the cutter head performs an arcuate generating movement about a generating axis in order to produce one of the gears, whereby a machining axis is adjusted relative to the generating axis in accordance with the position of the axes of both gears of the gear pair. In one advantageous embodiment, the same machining axis adjustment is also employed for fabricating the mating, non-generated gear.

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: A method and apparatus for shaping by generating for producing profiles on workpieces, especially on cylindrical gears. The workpiece and a shaping tool rotate continuously according to a fixed preset transmission ratio. The shaping tool additionally carries out an oscillating movement in the direction of its axis of rotation and thereby generates small cuts on the workpiece during at least two shaping rotations. The small cuts generated after each shaping rotation on the circumference of a circle of contact of the workpiece are provided on the workpiece displaced, relative to the small cuts made during the previous shaping rotation. The apparatus for carrying out the method includes a rotatably driven shaping tool, which carries out a stroke movement in the direction of its axis of rotation, and a rotatably driven clamping device for the workpiece, whereby the rotating motions of the shaping tool and of the clamping device occur continuously according to a fixed preset transmission ratio.

Abstract: Apparatus for milling a gear for a double enveloping worm gear drive. A rotating milling cutter is advanced toward a workpiece spindle to mill a flank of a gear tooth by tilting the milling cutter supporting frame about an axis that passes through the axis of rotation of the workpiece spindle to form a predetermined change in the helix angle from the top to the root of the tooth. The initial tilt setting of the cutter is adjusted to suit the root helix angle.

Abstract: A gear blank is integrally formed with a shaft or other central structure protruding axially from what is to be the toothed face of the gear. A spiral bevel gear is then cut by the face mill generation method, but with the cutter distance exceeding the outer cone distance. The cutter does not intrude into the area occupied by the shaft. The resulting gear has a negative spiral angle and a reverse tooth curvature.

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: The present invention relates to a bevolute gearing system which transmits torque between non-intersecting shafts at right angles to each other. The bevolute gear system includes a pinion gear which is flat and in one plane. The pinion gear is designed to include teeth which are shaped in the form of an involute spiral. The bevolute gear system includes a second gear which is also designed to include teeth which are shaped in the form of an involute spiral. The second gear is mounted on a non-intersecting axis at a right angle to the axis of the pinion gear. The bevolute gearing system of the present invention reduces the thrust loads to negligible values for the bearings of both the pinion gear and the second gear. In addition,. higher mechanical efficiencies, wider tolerances on alignment of the gears, interchangeability between the gear and the pinions to produce different ratios and a substantially eliminated gear noise are a few of the many advantages disclosed in the present invention.

Abstract: In a method of manufacturing gears with rolled or generated tooth flanks by cutting-out tooth slots or spaces with at least one face-mill cutter head performing a rotational movement about a cutter head axis, wherein the production capacity or efficiency is increased in that for rough cutting the tooth slots, during a first working step, the face-mill cutter head and the workpiece perform a plunge-cut movement with respect to one another. Hence, the cutters of the face-mill cutter head initially contact the workpiece at a predeterminable plunge-cut position between end regions of a tooth slot or space which is to be fabricated. For finish cutting the tooth slots, during a further working step, there is performed a generating movement between the face-mill cutter head and the workpiece.

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.

Abstract: A method of producing pairs of mating spur gears by cutting tooth gaps with a rotating end cutter head, wherein, in order to manufacture the one spur gear, one of the elements--the spur gear or the end cutter head--carries out an arcuate or circular rolling movement about an axis which coincides or approximately coincides with the gear axis of the other gear, and the other gear is produced by a cutting-in depth or plunge cut operation without any rolling movement.