US 7,306,047 B2Granted

Impact hammer drill

AssigneeHitachi Koki Co., Ltd.

InventorsHiroyuki Oda, Yukio Terunuma, Masayuki Ogura

Life of this patent

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Abstract

An impact hammer drill capable of performing drilling operation at a high speed with low noise and without requiring a large thrust. The drill includes a main shaft rotatable by an output shaft of a motor, and a spindle having an impact-receiving section and disposed over the main shaft slidably in its axial direction and rotatable together with the rotation of the main shaft. A piston is reciprocatingly slidably disposed over the main shaft for impacting against the impact-receiving section. A piston drive unit is disposed for driving the piston with a compressed fluid. A compressed fluid supplying unit is disposed for supplying the compressed fluid to the piston drive unit. A drill bit is attachable to the spindle. When performing drilling operation, the drill bit is imparted with a combined rotational motion and the reciprocal impact motion.

Claims12

Dependent claims

A drilling machine comprising:

a frame having one end;
a motor fixed within the frame and having an output shaft extending toward the one end of the frame;
a rotation shaft extending toward the one end of the frame and having an axis, the rotation shaft being coupled to the output shaft of the motor so as to rotate therewith, the rotation shaft including a slidable section disposed over an end portion of the rotation shaft which is configured so as to be slidable with respect to the rotation shaft and so as to prevent rotation of the slidable section with respect to the rotation shaft, the slidable section having one end provided with a drill bit attachment section and another end serving as an impact-receiving section;
a piston extending in parallel with an axial direction of the axis of the rotation shaft, and slidable in a reciprocatory manner in the axial direction to impact the another end of the slidable section;
a piston drive unit reciprocally driving the piston with a compressed fluid;
and
a compressed fluid supplying unit disposed within the frame for supplying the compressed fluid to the piston drive unit.

4 more elements

A drilling machine comprising:

a frame having one end;
a motor fixed within the frame and having an output shaft extending toward the one end of the frame;
a rotation shaft extending toward the one end of the frame and having an axis, the rotation shaft being coupled to the output shaft of the motor so as to rotate therewith, the rotation shaft including a slidable section having one end provided with a drill bit attachment section and another end serving as an impact-receiving section;
a piston extending in parallel with an axial direction of the axis of the rotation shaft, and slidable in a reciprocatory manner in the axial direction to impact the impact-receiving section;
a piston drive unit reciprocally driving the piston with a compressed fluid;
and
a compressed fluid supplying unit disposed within the frame for supplying the compressed fluid to the piston drive unit;
wherein the compressed fluid supplying unit comprises:
a coupling unit adapted to be coupled to a compressor which generates the compressed fluid;
an impact path forming portion that forms an impact path which communicates the coupling unit with the piston drive unit;
and
an impact path flow controlling unit disposed at the impact path for controlling a flow rate of the compressed fluid running through the impact path;
and
wherein the rotating shaft comprises:
a main shaft having one end, one end portion, and another end drivingly coupled to the output shaft, the main shaft being formed with grooves extending from the one end of the main shaft in the axial direction of an axis of the main shaft;
and
a cylindrical spindle functioning as the slidable section disposed over the one end portion of the main shaft, and slidable in the reciprocatory manner relative to the frame and the main shaft, the spindle having an inner peripheral surface, a front end functioning as the drill bit attachment section, and a rear end functioning as the impact-receiving section, the spindle also having protrusions protruding from the inner peripheral surface, each protrusion being slidably engageable with each groove to allow the spindle to be axially moved relative to the main shaft but prevent the spindle from being rotated relative to the main shaft.

14 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/049,688Filed 4 Feb 2005
Priority: JP P2004-0319629 Feb 2004
Published: US 2005/0173140 A111 Aug 2005
Granted: 11 Dec 2007
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

B25D 9/04
Portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated…
B25D 16/00
Portable percussive machines with superimposed rotation , the rotational movement of the
B25D 17/22
Devices for cleaning or cooling tool or work: using pressure fluid
B25D 2216/0023
Details of percussion or rotation modes: tools having a percussion-and-rotation mode