Abstract: An apparatus for grinding cylindrical gears by means of a generating method, comprising two substantially plate-shaped grinding wheels for machining a right tooth flank and a left tooth flank of the gear by means of a practically point-shaped contact zone disposed at a respective lateral edge of each grinding wheel. A respective grinding support is provided upon which there is mounted an associated one of the grinding wheels, and means pivotally mount each grinding support at the region of the associated grinding point.

Abstract: A marine gear drive has two drive pinions for coupling to respective high-speed and low-speed engines and both pinions connected through intermediate gears to a common larger gear adapted to be coupled to a propeller shaft. The drive pinions, intermediate gears and larger gear are disposed in only two planes and one drive pinion is in the driving train from the other drive pinion to the larger gear. An arrangement for a twin propeller drive, with each propeller driven by high-speed and low-speed engines as aforesaid, counter-rotates the propellers without reversing the direction of rotation of the drive inputs.

Abstract: A generating method and apparatus for grinding cylindrical gears by means of two substantially plate-shaped or dished grinding wheels which machine a right tooth flank and a left tooth flank by means of practically point-shaped contact zones disposed at their related lateral edge. Between the gear and both grinding wheels there is accomplishd a to-and-fro generating motion in relation to the base circle or cylinder of the gear. The connection line between the contact zones of the grinding wheels is maintained at such a spacing from the base circle that in each end or terminal position of the generating motion one grinding wheel machines a tooth tip and at the same time the other grinding wheel machines a tooth root.

Abstract: Apparatus for machining gear teeth has a template control arrangement for varying the tooth flank shape longitudinally of the flanks. This arrangement comprises co-operating wedges, one fixed to the machining tool and the other to a moving tool carrier that makes the working stroke of the tool, the tool being displaceable relative to the carrier by the wedges to vary the tool position radially of the workpiece as it moves along the flanks. The carrier wedge slides in the carrier transversely to the working strokes and the template follower is fixed to slide with it, whereby the variation of the tool radial position is directly proportional to the template profile.

Abstract: A correction device for the rolling tape tension on a gear grinding machine, especially a form grinding machine for spur and helical cylindrical gears, comprising tapes subjected to an initial basic tension at rest, the tapes being attached at one end to a rolling block, and there occurring between the rolling block and the tapes a relative rolling action. The tapes are attached at their other end to a tape stand which is movable to-and-fro. At the tape stand intermediate pieces or tape clamps are mounted on a device which imparts an additional torque on the rolling block. A gauging device measures the tension in the rolling tapes and compares it with the initial tension of the system at rest.

Abstract: Gear tooth testing apparatus with a rotary test gear mounting has a mechanism for controlling the relative movements of a test probe and of the gear under test, the motions being interconnected by a lever pivotable about the gear mounting axis. The lever has a second pivot connection to a straight-edge that rolls on a rolling cylinder co-rotating with the gear to generate an involute motion, and a third pivot connection to an auxiliary slide associated with the probe. The lever is longitudinally displaceable with respect to all three pivot axes whereby its position relative to the pivot axes at different settings of the apparatus is controllable in a manner limiting the necessary size of the apparatus for a given working capacity.

Abstract: For grinding the flanks of gear teeth to modify an involute tooth profile determined by the generating method of grinding, the tooth flank area is associated with a system of co-ordinates and a grinding programme is employed that specifies involute modifying grinding feed in terms of the co-ordinates. By comparison of actual and programmed feed positions at instantaneous points in the co-ordinate system, feed corrections are applied at those points to obtain the programmed profile. By interpolation between successive comparison points, incremental feed corrections are obtained to give a smoother change of profile.

Abstract: A heavy duty dog clutch has co-axial driving and driven shaft elements each with a toothed connection to an intermediate sleeve that is axially displaceable to make and release one of said connections. The toothing of the releasable connection is helically formed so that a given direction of driving torque tends to screw together the helical toothing. One of the shaft elements is capable of axial displacement by the reaction to said torque in the helical toothing and this causes a pair of abutment surfaces on the shaft elements to bear against each other to engage the clutch fully.

Abstract: Gear pitch testing apparatus has a computer control for programming relative displacements between a gear and a pair of probes, and means for automatically comparing test data with stored reference values to indicate deviations in the gear under test. Initial setting of the apparatus for a test sequence requires the operator only to control the relative displacements of the gear and probes to synchronise them approximately, the coarse adjustment thus obtained then being automatically modified in an electronically controlled fine adjustment stage to co-ordinate the movement between the gear and the probes accurately and allow such characteristics as absolute cumulative pitch error to be evaluated.

Abstract: A gear tooth profile testing apparatus has a pair of displaceable measuring devices, one of which is movably mounted on an adjustable base plate and has the other device movably mounted on it. A probe mounted on said other device has biassing means urging it against the profile under test. Drive means displace one of the devices, which transmits signals of relative movements between the two devices to a computer. The computer receives from the other device signals of its movements relative to the base plate. The computer compares these measurements of probe movement with reference values to evaluate deviations in the measured profile.

Abstract: A feeler device has a feeler element pivoted on a carrier for measurement of relative movements between the element and carrier. The element can be located in alternative end positions from which the relative movements take place. The end position is selected by adjustment of a rotatable ring that has a camming surface acting on springs which provide the biassing action that causes one or other end position to be assumed.