US 6,431,294 B1 · Percussive tool

Abstract

A percussion drill 10 has a tubular fluid transmitting body 14, with a drill bit 16 mounted on a drill bit support 20 itself mounted in body 14 via a spring 22 and salines 24. A mass 28 is spring mounted in the body 14 and is movable to impact on a face 26 of the support 20. Mounted to the mass 28 is a rotating valve 32 comprising two valve plates 34, 36. Each plate 34, 36 defines a slot 38, 40, such that rotation of one of the valve plates 36 relative to the other moves the slots 38, 40 into and out of alignment; the change in alignment of the slots 38, 40 alters the flow of drilling fluid through the valve 32, so altering the drilling fluid pressure force acting on the mass 28, so causing mass 28 to push against the spring 30, and impact on the drill bit support 20 providing a percussive act ion at the drill bit 16.

Claims24

Dependent claims

A percussion drill comprising:

a fluid transmitting body;
a drill bit support coupled to the body;
a mass movable relative to the body for impacting on the drill bit support;
means associated with the mass for creating a fluid pressure force on said mass;
a rotating valve located in the body for controlling flow of fluid through the body to produce a varying fluid pressure force on the mass and induce acceleration of the mass;
and
a valve motor for driving said valve.

4 more elements

Dependencies are inferred from the claim text.

Percussive tool

Life of this patent

Percussive tool

Life of this patent

Abstract

Claims24