US2589047A

US2589047A - Claw hammer with extensible fulcrum

Info

Publication number: US2589047A
Application number: US176902A
Authority: US
Inventors: Harvey H Brown; Leland W Williams
Original assignee: NAILMASTER Inc
Current assignee: NAILMASTER Inc
Priority date: 1950-07-31
Filing date: 1950-07-31
Publication date: 1952-03-11
Anticipated expiration: 1969-03-11

Description

March 11, 1952 H. H. BROWN EI'AL 2,589,047 I CLAW HAMMER WITH EXTENSIBLE FULCRUM Filed July 31, 1950 Inventor:

Harvey H. Brpyn Leland W- WI/llG/DS Patented Mar. ll, 1952 UNITED STATES PATENT OFFICE CLAW HAMMER WITH EXTENSIBLE FULCRUM Application July 31, 1950, Serial No. 176,902

4 Claims.

This invention relates generally to hand tools and more particularly to a claw hammer having an extensible fulcrum member.

A primary object of this invention is to provide a claw hammer capable of pulling nails without bending the same, So that these nails may be reused.

Another object of this invention is to provide a claw hammer with an extensible fulcrum so that the ease of pulling nails is increased and the tendency to mar the surface of the material in which the nail is lodged is decreased.

Yet another object of this invention is to provide an extensible fulcrum construction whereby a substantially conventional configuration of the head of the hammer is achieved when the fulcrum member is retracted, and the balance of the hammer is maintained.

Yet another object of this invention is to provide an extensible fulcrum construction which can be used with almost all types of claw hammers, the unit being self-contained and insertable into a conventional claw hammer by merely providing a bore in the end of the handle upon which the head of the hammer is secured.

Yet another object of this invention is to provide an extensible fulcrum member construction wherein the fulcrum member per se is merely rotated to 90 degrees in order to lock the same in extended position, there being no latches or exposed mechanism to interfere with the normal use of the hammer.

A last object to be mentioned specifically is to provide an extensible fulcrum assembly for claw hammers wherein a minimum of adaptation of conventional claw hammers is necessary in order to incorporate this extensible fulcrum assembly, the device being relatively inexpensive and practicable to manufacture, simple, safe and convenient to use, and adapted to give efiicient and durable service.

With these objects definitely in view, this invention resides to certain novel features of construction, combination and arrangement of elements and portions as will be hereinafter described in detail in the specification, particularly pointed out in the appended claims, and illustrated in the accompanying drawings which form a material part of this application, and in which:

Figure l is a view, in perspective of a hammer head and a portion of a hammer handle, with this invention incorporated therein and with the fulcrum member retracted;

Figure 2 is a side elevational view, portions be- 2 ing broken away to show the underlying portions largely in vertical section;

Figure 3 is a view, similar to Figure 1 but showing the fulcrum member extended and locked by turning the same through degrees;

Figure 4 is a vertical sectional view taken substantially on the line 4--4 in Figure 2; and

Figure 5 is a view, in perspective of the fulcrum member assembly removed from the hammer.

Similar characters of reference designate similar or identical elements and portions throughout the specification and throughout the different views in the drawings.

Referring now. to the drawings in detail, this invention is adapted to be used with a hammer which is essentially conventional and will have a handle [0 with a portion 12 of rectangular crosssectional shape to fit within a conventionally provided recess [4 in the hammer head IS. The hammer head is provided with opposed lateral recesses I8 which are separated from the central recess H by walls 20 of reduced thickness, these walls being preserved in order to prevent undue weakening of the hammer head. The lateral recesses l8 communicate with a transverse recess 22 on the side of the head It remote from the handle [0.

The device includes a fulcrum member which is generally U-shaped with side plates 24 and an end plate 26. An elongated pin 28 is axially disposed with reference to the fulcrum member and is integrally secured to the inner face of the end plate 26. When the fulcrum member is retracted the side plates 24 are recessed in the lateral recesses l8.

The pin 28 is slidably received in an aperture 30 in an end plate 32 of an elongated bushing 34 which is tightly secured within the bore 38 provided axially of the portion I2 of the handle II]. It is important to note that the elongated bushing 34 has an axial bore 39 of approximately the same transverse dimension as the portion of the bore 38 which is not enlarged by the bushing when the latter is driven into the handle. The immediately foregoing sentence refers to hammers wherein the handle is constructed of wood or some other material which is slightly deformable, it being remembered that the elongated bushing 34 is slightly tapered. This bushing 34 will also be provided with sharpened ridges 36 to prevent inadvertent withdrawal of the bushing from the bore 38 in the hammer handle.

In order that the fulcrum member may be biased into retracted position, as indicated in 3 Figure 1, the spring 40 of helical type is compressed between the apertured end plate 32 and an element 42 secured to the inner end of the pin 28, this element ordinarily taking the form of a split washer 42 secured in an annular groove, not shown, in the said inner end of the pin 28.

The operation of this invention will be clearly understood .from a consideration of the foregoing description of the mechanical details thereof, taken in connection with the above recited objects and the drawings. In recapitulation, it might be added that the side plates 24 are of a dimension corresponding generally with the dimensions of the lateral recesses l8, and side plates 24 fit within these recesses l8 when the fulcrum member is in retracted position, as indicated in Figure 1. When it is desired to extend the fulcrum member, the operator grasps the fulcrum member by the side plates 24, which may be knurled, if desired, and pulls outwardly against the action of the spring 40, until the side plates 24 clear the head l6, and the fulcrum member is then rotated 90 degrees about the pin-28-as axis, and the sideplates 24 then allowed to enter the transverse'recess 22. The fulcrum member is then prevented from retraction and the claw hammer-is used for withdrawing nails, without the bending of these nails when the heads of the nails are disposed at some considerable distance from the material in which the shanks of the nails are lodged. Obviously, the fulcrum member is automatically'retracted when the same is pulled outwardly slightly from the head I6 and again rotated through 90 degrees.

It will be clear that all of theabove recited objects are amply achieved by this invention and further description would appear unnecessary.

Having described the invention, what claimed-as new is:

1. In a-claw hammer, a-handle having a-bore in one end and a head tightly secured on said one end of the handle, an elongated tubular bushing secured in said bore, a pin extending rotatably and slidably into said bushing, a coiled spring coaxial with said pin and within said bushing and engaging said pin and bushing to bias said pin against withdrawal from the bushing, a fulcrum member carried by the outer end of said pin, and means to hold the. fulcrum member extended outwardly from said head in a direction axial of said pin and against the action of said spring.

2. Apparatus according to claim 1, and wherein said means comprises a side plate integral with said member and disposable laterally of said head when the member is retracted and disposable transversely of the head when the member is extended.

3. Apparatus according to claim 2 and wherein said side plate is provided in duplicate, and said head is laterally recessed to receive the side plates when the member is retracted.

4. Apparatus according to claim 1, and wherein said pin has an element on the end thcreQfIemote from said fulcrum member; and said bushing has an ,end plate ,apertured to accept said pin and disposed adjacent said member, and said spring is compressed between said end plate and said element.

HARVEY H. BROWN. LELAND W. WILLIAMS.

REFERENCES CITED The followingre'ferences are of record ,inthe file of this, patent:

UNITED STATES PATENTS Number Name. Date 651,629 Jordan et al., June 12, .1900 736,797 Steele Aug. .18, .1903 856,097 Palmer. June V4, 1907 1,410,407 Luttrell Mar. 21, 1922