The article discusses the issues of improving the technology of cutting teeth of cylindrical gears using modular precast disk milling cutter in various production conditions for gear milling, reducing the cost of tooling materials and facilitating the manufacture of precast disk mills by changing the design. The essence of this design is that when cutting teeth into gears with an involute profile, radial runout is eliminated to a minimum, since the gear cutting operation is carried out on the machine in which the turning was performed. The proposed new gear processing technology – with an involute profile shape and engineered efficient design of prefabricated disk cutters. The main place in the article is given to the design parameters of gear cutting mills, as well as their advantages and disadvantages. Much attention is paid to the determination of the structural and geometric parameters of cutters with various cutting patterns. The described methods are applicable for the design of tools in small-scale production of gears.

To date, use of moment-transmitting joints with an EP-profile in lieu of splined and keyed joints has been suppressed by lack of specialized highly productive domestic equipment with an acceptable price tag. In this connection, means of implementing conversion of a different kind of moment-transmitting joints to a noncircular profile on the basis of procedures and equipment that exist at establishments involved with the building of farm machinery are under development at the Tashkent State Technical University. The procedure of fabricating splined joints was adopted as a base. The typical procedure for the machining of slotted openings in farm-machine and compressor building consists in pull broaching in a single or several passes and heat treatment with subsequent calibration; in that case, a degree of accuracy corresponding to a quality grade of approximately 9 is attained. After grinding the external surface, splined shafts with a setting along the external diameter are machined on a slot-milling machine with subsequent heat treatment. In the majority of cases, the shafts are not machinod after heat treatment, although more precise splined shafts, which can be subjected to slot grinding, have recently come into increasingly broader use. This operation, however, is not very productive.For the pull broaching of noncircular openings and subsequent machining, it is necessary to work out the design and fabrication procedure for the pull broaches, arbors and gage calibers, the noncircular profiles of which should correspond with an accuracy to quality grades of 6-7. When there are no special grinding machines, various models of back-off lathes and thread grinders are suitable for this purpose. The following scheme is used to form an EP-profile [1]: a rotating shaR is machined by a harmonically oscillating "cutting plane," the oscillation frequency of which exceeds the rotational speed of the shaR by a factor of a whole number equal to the number of faces on the EP-profile. In that case, harmonic oscillations are impart~ to the tool by a cam-eccentric, which is kinematically linked with the rotating mechanism of the shaft being machined. The "cutting plane" is simulated by the face of the grinding wheel on the backing-off lathe, or the periphery of the wheel on the thread grinder. In the latter case, no EP-profile is formed, but rather the equidistance of a sinoid similar to the EP-profile with an accuracy to 0.01-0.02 nan. To generate a profile that approaches as closely as possible the EP-proffle, we can, in this ease, turn the grinding wheel about the axis normal to the shaft being machined by an angle defmed by the dimension of the EPprofile and the width of the grinding wheel. In that case, deviations from the correct profile do not exceed limits corresponding to a quality grade of 6-7, and depend primarily on the machine's precision.The machining of noncircular openings consists mostly in single-pass pull broaching after drilling and fmishing by boring or countersinking. Occasionally, we are restricted only to ...

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This article presents the results of a study of the process of internal fluid leakage in the design of a gear pump with a biaxial connection. It is known that the volumetric efficiency mainly depends on the leakage of the working fluid through the gaps formed by the tooth heads and the pump casing, as well as between the end surfaces of the gears and the side walls of the casing. In addition, additional leaks occur along the contact line of the teeth. To reduce radial leaks, the gap between the gears and the pump casing is minimized, and to reduce end-leakage, the side walls are automatically pressed against the end surfaces of the gears by liquid under operating pressure. The design of the pump shows that the main internal fluid leaks occur in the gap between the gears and the housing. Naturally, these leaks require excessive energy consumption and, thereby, reduce the efficiency of the pump. The natural way to combat this circumstance is to reduce the marked gaps to a minimum. This is possible using an additional element - a biaxial sleeve. The dependence of the spring force on the fluid flow rate and the guaranteed gap between the ring gear and the pump casing has been analytically established. They are characterized by a drop in force with an increase in clearance and a rise in flow rate. This is due to an increase in the dynamic force in the gaps, which must be compensated by the spring.