# US 4,399,978 A · Hand tool with variable inclined head

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- Number: US 4,399,978 A
- Document ID: US4399978A
- Status: Granted
- Kind: A
- Application number: 06/352,810
- Filed: 1982-02-26
- Granted: 1983-08-23
- Earliest claimed: 1982-02-26
- Inventors: Charles H. Moore
- Web page: https://patentgrep.com/patent/US4399978A

## CPC

- B25G 3/38: Hinged, pivoted, swivelling, or folding joints
- B25D 1/00: Hand hammers {(handles therefor B25G1/00; attachment of handles to the hammer head B25G3/00)}; Hammer heads of special shape or materials
- B25G: HANDLES FOR HAND IMPLEMENTS (attaching the blades or the like to handles of hand tools for soil working A01B1/22; handles of hand implements for harvesting A01D1/14; handles integral with brushware A46B)
- B25D: PERCUSSIVE TOOLS {(percussive machines for forging B21J; hand-held drilling machines, in general B23B45/00, for wood B27C3/08; drilling machines, used for mining or quarrying, with reciprocating tool which is turned intermittently when out of contact with the working face E21B1/00)}

## Abstract

A small hand tool such as a carpenter's hammer is disclosed as having a head which is pivotally connected crosswise to its handle. The head is provided with abutment faces which at different inclinations of the head to the handle are selectively aligned with the blunt end of a latch rod threadedly connected to the handle within a provided axially extending bore. Rotation of a larger-sized operating knob at the rearward end of the handle effectively advances and retracts the latch rod to releasably lock the hammer head to the handle in the selected position to which it is adjustable thereon.

## Claims

### Claim 1

In a carpenter's hammer or like small hand tool having an elongate handle and a tool head mounted crosswise of the handle, the improvement wherein
the tool head embodies an intermediate attachment portion of rigid metal having a pair of work portions projecting laterally from opposite sides of the attachment portion, one of said work portions being a solid butt useful in pounding;
the elongate handle being of rigid metal and containing a longitudinally extending, axially-centered through-bore which opens through both the forward and rearward ends of the handle;
a pair of parallel spaced hinge ears integral with and projecting axially of the forward end of the handle;
the rearward end of said tool head attachment portion disposed in said space between the hinge ears; and
a pivot pin pivotally connecting said attachment portion to the hinge ears, the axis of said pivot pin intersecting the longitudinal axis of said tool head attachment portion and said handle through-bore at right angles thereto;
the surrounding periphery of the tool head attachment portion embodying first, second and third planar abutment faces circumferentially spaced about said axis of the pivot pin and radially spaced equidistantly from said pivot pin axis at a distance less than the separation of the pivot pin from the forward end of the elongate handle;
the through-bore of the elongate handle having a circumferentially threaded wall portion immediately behind the forward end of the elongate handle;
a rigid metal latch rod in said handle through-bore extending axially thereof;
said rod having a planar forward end disposed normal to the axis of said rod and an exteriorly threaded portion by which it is threadedly connected to the handle, said externally threaded portion of the latch rod being disposed immediately behind its forward end;
a hand grip portion fixed to and surrounding the rearward end of said elongate handle for manual grasp in use of the tool;
an externally accessible knob operatively connected to the rearward end of the latch rod beyond the handle and its hand grip portion such that when rotated in one direction the forward planar abutment end of the latch rod is drawn into the forward end of the handle bore freeing the tool head to swing on the pivot pin and when rotated in the counter direction is moved outwardly therefrom into the space between the handle hinge ears so as to positively engage that one of the abutment faces of the tool head attachment portion aligned therewith and to lock the tool head to the handle;
the threaded forward portion of the latch rod having an axial length greater than that of the threaded portion of the handle such that the latch rod remains connected to the handle both when its forward end is fully retracted into the through bore of the handle and when expanded to engage with a selected one of the abutment faces of the tool head attachment portion aligned with the axis of the through-bore;
said knob having a diameter greater than that of the elongate handle such that the tool head can be positively locked both in the positions to which the tool head is adjusted on its hinged connection to the elongate handle and to prevent slippage of the user's grip on the tool in his use thereof.