Atlas Copco Tools Ab

Mats C Holmin

Sten Herman Olsson

Lars T Skogsberg

Knut Christian Schoeps

John Robert Christian Friberg

Torbjörn Rafael Sjöblom

Christa Maria Karlberg, Legal Representative

Nils Gustav Erland Karlberg

Bengt G Wallerius

A number of pre-production calibration tightenings are performed at a screw joint identical to a screw joint used in production and using the same impulse wrench as to be used in production tightening. The value of one or more tightening related parameters are registered at the attainment of the desired pre-tension level, and those parameter values are used to statistically form a basis for a reference set-up. The tightening parameter values registered during production tightening are compared to the reference set-up, and an indication is obtained as to discrepancies between the reference set-up and the actually registered parameter values to get an indication as to whether the impulse wrench is malfunctioning and/or the screw joint is faulty.

Method for quality checking a screw joint tightening process performed by a torque impulse wrench

Torque impulse tool with automatic power shut-off comprising two inertia

An angle type power nutrunner having a housing (10) with a rotation motor, an angle head (15) with an output shaft (13), and a thread connection (21) including a lock nut (22) for securing the angle head (15) to the housing (10). The housing (10) is provided with a first group of radial holes (25) disposed in a circumferentially directed row and the angle head (15) is provided with a second group of radial holes (26) disposed in a circumferentially directed row, and a key pin is arranged to positively define alternative angular positions between the angle head (15) and the housing (10) by engaging selectively one hole each of the first and second groups of holes. The pitch of the first group of holes (25) is different than the pitch of the second group of holes (26) for enabling a small angle adjustment of the angle head (15) in relation to the housing (10).

Angle type power nutrunner

A torque responsive release clutch mechanism for a pneumatic power nutrunner having a housing (16) with an air inlet passage (11) and an air motor (12). The clutch mechanism includes a driving clutch half (22) with pockets (33) for two or more torque transferring balls (24), a bias spring (38), and an axially displaceable thrust element (34) for transferring the bias spring load to the balls (24), and a driven clutch half (23) having cam surfaces (25) for cooperation with the balls (24), wherein the driving clutch half (22) includes means (36, 44, 45) for feeding pressure air to the cylinder chamber (30), and the thrust element (34) has a cylindrical skirt portion (43) for sealing guidance in the cylinder chamber (30). A valve (44, 45, 48, 49) is arranged to accomplish a bias spring (38) compressing air force on the thrust element (34) as the latter has been initially displaced a certain distance by the balls (24) at release of the clutch.

Torque responsive release clutch mechanism

A vibration insulated power tool handle, comprising a tubular grip portion (10), a mounting means (11) for rigid mounting on a tool housing, and an elastic vibration insulating leaf spring membrane (12) interconnecting the grip portion (10) and the mounting means (11). The spring membrane (12) is formed with a central opening (19) for receiving a screw (21) of the mounting means (11) and is connected by its periphery to a socket portion (16) on the grip portion (10).

Vibration insulated power tool handle

A vibration damped hand held rotary grinding machine comprising a housing (10) with at least one handle (17, 18), a rotation motor (11), an output shaft (13) drivingly coupled to the motor and having a mounting (14) for attachment of a grinding wheel (15), and a sector-shaped non-resilient safe guard (19) which is rigidly attached to the housing (10) and surrounding partially the grinding wheel (15) and which has an arc-shaped rim portion (20) encircling partially the grinding wheel circumference. A vibration damping inertia device (22; 22a, 22b) is rigidly associated with the safe guard (19) on or adjacent the rim portion (20), such that the center of gravity of substantially all axial plane cross sections through the inertia device (22 22a, 22b) is located at a radius (R.sub.1) of at least 90% of the rim portion (20) radius (R). Preferably, the safe guard (19) is semicircular and th einertia device (22; 22a, 22 b) extends from both ends of the safe guard rim portion (20).

Growing community of inventors

Stockholm, Sweden

Mats C Holmin