PORTABLE MACHINE TOOL FOR WORKING END FACES Russian patent published in 2000 - IPC

FIELD: metal cutting, namely apparatuses for working end ring-shape surfaces, possibly in power engineering industry branches, for example at repairing operations in nuclear power plants. SUBSTANCE: portable machine tool includes cutting head having stationary body and movable body with mechanism for radially feeding tail spindle with cutter holder, reduction gear of drive unit kinematically joined with movable body, mechanism for securing machine tool on worked part, two counterweights, two coaxial central thrust bearings, at least two coaxial radial bearings. Support provided with flexible members for mounting reduction gear of drive unit is mounted with possibility of fixation onto outer lateral surface of worked part by means of said flexible members. Mechanism for radially feeding tail spindle is in the form of differential screw and two nuts. One nut is mounted on movable body; another nut is rigidly joined with tail spindle. Kinematic connection between movable body and mechanism for radial feed of tail spindle is in the form of two mutually engaged cylindrical gear wheels and two mutually engaged cone gear wheels. One cylindrical gear wheel is mounted in stationary body coaxially with rotation axle of movable body; other cylindrical gear wheel is mounted on shaft placed in movable body in parallel to its rotation axis. One cone gear wheel is mounted on said shaft, other cone gear wheel is mounted with possibility of free axial motion on differential screw of mechanism for radial feed of tail spindle. Movable body is mounted on stationary one by means of two coaxial central thrust bearings and at least two coaxial radial bearings embracing the above mentioned shaft with cylindrical and cone gear wheels and rotation axle of movable body. One counterweight is secured to movable body diametrically opposite relative to cutter holder. Another counterweight is secured to end of differential screw opposite to cutter holder. Mechanism for fixing machine tool onto worked part is in the form of mounting plate with apertures. At least one of said apertures is designed for basing and joining with cutter head and at least two of said apertures are designed for fixing assemblies for securing mounting plate to end face of worked part with possibility of radial shift. EFFECT: enhanced accuracy of basing, increased rigidity, lowered vibration of "machine tool-cutter-worked part" system, reduced time period for mounting-dismounting machine tool onto worked part with possibility of manual performing of such operations. 4 dwg