Information
-
Patent Grant
-
6477922
-
Patent Number
6,477,922
-
Date Filed
Monday, October 25, 199925 years ago
-
Date Issued
Tuesday, November 12, 200222 years ago
-
Inventors
-
-
Examiners
- Morgan; Eileen P.
- Danganan; Joni B.
Agents
-
CPC
-
US Classifications
Field of Search
US
- 081 20
- 081 21
- 081 22
- 081 25
- 081 26
-
International Classifications
-
Abstract
An impact tool having a head structure including first head piece, a second head piece and an elongated handle structure. With a lengthwise section of the handle structure being arranged in operative association with and maintaining the first and second head piece of the head structure in operative combination relative to each other. A woven fiber material is arranged about and epoxied to the lengthwise section of the handle structure arranged in operative association with the first and second heads to enhance the interface therebetween.
Description
FIELD OF THE INVENTION
The present invention relates to hand held manually operated tools and, more particularly, to impacts tools such as hammers and the like having a head structure including two separated members which are joined by an elongated handle structure.
BACKGROUND OF THE INVENTION
Impact tools such as hammers, axes, picks and other hand held manually operated striking tools are well known and have been used for centuries. Each of these tools come in a variety of shapes and sizes. The specific construction of the impact tool varies widely according to the desired specified use.
Such tools are typically provided with a one-piece head structure formed from steel or the like and usually includes two metallic impact or striking surfaces. Carpentry hammers typically have a metal striking head at one end and a claw configuration at an opposite end. Alternatively, the hammer can include heads formed from a softer material such as lead or hardened rubber material to provide nonmarring impact surfaces.
Hammers typically have included a handle extending away from the head structure to provide the hammer with a generally T-shaped configuration. The one-piece head structure is typically created from a forging operation to add strength to the head structure of the impact tool. Typically, a lengthwise portion of the handle fits through a bore or opening provided in the one-piece head structure. A wedge or other suitable fastening device is driven into the free end of the handle to fasten the handle to the head structure.
When a tool such as a hammer is moved to strike a surface of an object, part of the kinetic energy developed through the hammer's swing is utilized in doing the desired work on the object being struck, another part is dissipated as heat, while another part is converted into potential energy in the form of recoil or rebound of the hammer from the surface being struck. The distortion of the striking surface of the hammer has potential energy much the same way as a compressed spring. It is this potential energy that causes the hammer to recoil or bounce back from the surface of the object being struck. Moreover, hammers usually transmit some force of the impact to the user's hand, which will increase efforts and labor of the user, thus reducing the operating efficiency of the tool.
To reduce this problem, there have been developed hammers offering a “dead-blow” characteristic. For example, attention is directed to my U.S. Pat. No. 5,408,902, offering a composite hammer embodying a split head design wherein a non-load bearing internal head assembly is carried by a rigid outer load bearing framework which provides strength and stiffness to the tool. The “dead-blow” characteristic offered by my patented tool is accomplished through a split head tool design that remarkably reduces and substantially eliminates transference of the impact from the striking head to the user's hand.
While the invention disclosed in my U.S. Pat. No. 5,408,902 offers significantly improved results over other impact tool designs, there is and industry mandates a continuing effort to improve product technology. As a result of those continuing efforts, the present invention has been realized.
SUMMARY OF THE INVENTION
In view of the above, and in accordance with a preferred form of the present invention, there is provided an impact tool including a head structure with first and second members extending in opposite directions from each other but which are maintained in interconnected relationship relative to each other by a handle structure extending normally from and secured to the head structure.
In one form of the invention, the members of the head structure are formed from metal. In that embodiment wherein the impact tool is configured as a hammer, at least one of the members of the head structure is a striking head which can include an exposed metal striking surface. The other member of the head structure for the hammer can be configured as a claw or, alternatively, a second striking head with an exposed metal striking surface.
In a preferred form of the invention, each member of the head structure includes a working portion and an attachment portion. The attachment portion of each member of the head structure extends, at least partially, in surrounding relation relative to a lengthwise portion of the handle structure so as to prevent the member from becoming disassociated with the handle. Forming the attachment portion of a claw-like configured head with a clevis-like configuration appears beneficial to distribute forces imparted thereto during operation of the tool.
The handle structure includes an elongated handle formed from any of a myriad of materials selected from the class comprising; wood, plastic, metal, nylon, fiberglass, an elastomer, or suitable rigid material. In a preferred form, the handle structure further includes a wedge-like member driven into the free end of the handle. The wedge-like member serves to maintain the handle structure and head structure in secured engagement relative to each other.
In accordance with one aspect of the present invention, and while remaining interconnected through the handle structure, the members of the head structure are separated from each other in an axial direction. The spacing between the members of the head structure allows for movement of the head structure members in response to one of the head structure members being struck against a surface. That is, when one member or head of the head structure is struck against a surface, the spacing between the heads or members of the head structure allows the unstruck head to move toward and impact against the struck head thereby providing a secondary blow that inhibits the tool's struck head from rebounding from the struck surface and thereby dampening vibration through the handle.
In a preferred form of the invention, the attachment portions of the heads or members of the head structure are configured with confronting impact surfaces. The spacing mentioned above is provided between the impact surfaces on the heads or members of the head structure. The range of spacing between the members of the head structure varies and is dependent upon a number of factors. That is, the spacing between the members of the head assembly varies as a function of the mass distribution or geometry of the head structure members, the material from which the head structure members are formed, the timing of the collision between the head structure members, and the length of time the striking surface of the head structure striking member remains in contact with the struck surface. A spacing between the impact surfaces ranging between about 0.010 inches to about 0.070 inches appears appropriate.
To promote movement of the members or heads of the head structure moving toward each other in response to use, the tool of the present invention can further include elastomeric material disposed between the handle of the tool and the heads or members of the head structure. The elastomeric material has a hardness ranging between about 40 Shore A durometer hardness and about a 95 Shore A durometer hardness. Suffice it to say, the elastomeric material acts as a spring for returning the nonstruck head to a normal or operational position after moving toward and impacting with the struck head or member of the head structure. Accordingly, any suitable material which, during operation of tool, will initially compress and subsequently return the unstruck head to an operational position will suffice.
Another aspect of the present invention relates to configuring at least one of the members of the head structure from laminations. The other member or head of the head structure is captively received between laminations of the other member. After captively arranging the heads or members of the head structure relative to each other, the laminations are fixedly secured to each other. The handle of the tool extends through and is maintained in association with either of the members or heads of the head structure and extends generally perpendicular relative thereto.
With this aspect of the present invention, a striking plate or cap can be arranged in combination with the laminations. The striking plate defines a striking surface for the tool and, thus, inhibits separation of the laminations during use of the tool.
With the present invention, the head structure preferably comprises dual heads or members which are generally axially aligned relative to each other. Because the heads or members of the head assembly of the present invention can be manufactured separately, the manufacturing equipment and processes for forming the heads or members of the head structure are significantly simplified, thus, reducing manufacturing costs and thereby enhancing the selling price of the tool. Configuring one or more of the striking heads with laminations furthermore enhances the manufacturing process.
Arranging elastomeric material between the heads and the handle of the tool furthermore enhances this invention. The elastomeric material effectively isolates the heads from the handle and thereby significantly reduces vibration transfer from the head structure through the handle and to the user's hand.
The concept of splitting the heads of the head structure to allow for axial movement of the heads relative to each other furthermore enhances performance characteristics of the present invention. Thus, when one head or member of the head structure is struck against a surface, the other head or member of the head structure acts as a lagging mass and provides a secondary blow to inhibit the struck head from rebounding from the surface being struck. According, an advantageous “dead-blow” feel is provided to the tool. It has been found that vibrations normally experienced in the handle of the tool are not discernable with the tool designed in accordance with the present invention.
Still another aspect of the present invention involves arranging a skin of resin impregnated fiber material, preferably an arimid fiber material, along and about the lengthwise portion of the handle structure extending into operative association with the head structure of the impact tool. Preferably, an epoxy is used in combination with the fiber material or skin. Moreover, the fiber skin or material plus the epoxy defines a more cumbersome path for impact vibrations to traverse between the striking head of the head structure and the handle structure thereby significantly reducing vibration transference during use of the tool. Additionally, a cosmetic cover is preferably arranged beneath the head structure and extends about the handle of the handle structure to aesthetically cover any free ends of the fiber material extending from the head structure of the tool. As will be appreciated from an understanding of this aspect of the present invention, the presence of an epoxy material about that portion of the handle structure extending into operative combination with the head structure will enhance securement of the head structure and handle structure to each other while advantageously dampening vibrations whether the head structure is of a unitary design or of the two piece design as disclosed above.
These and other objects, aims, and advantages of the present invention will become more readily apparent from the following detailed description of the invention, the appended claims, and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a top plan view of an impact tool embodying features of the present invention;
FIG. 2
is a sectional view taken along line
2
—
2
of
FIG. 1
;
FIG. 3
is a sectional view taken along line
3
—
3
of
FIG. 1
;
FIG. 4
is an exploded perspective view of the members forming a head structure of the impact tool illustrated in
FIG. 1
;
FIG. 5
is a top plan view of the alternative embodiment of the present invention;
FIG. 6
is a sectional view taken along line
6
—
6
of
FIG. 5
;
FIG. 7
is a longitudinal sectional view of another alternative form of the present invention;
FIG. 8
is a top plan view of another alternative embodiment of the invention;
FIG. 9
is a sectional view taken along line
9
—
9
of
FIG. 8
;
FIG. 10
is a top plan view of yet another alternative form of the present invention;
FIG. 11
is a sectional view taken along line
11
—
11
of
FIG. 10
;
FIG. 12
is a top plan view of another alterative form of the present invention;
FIG. 13
is a sectional view taken along line
13
—
13
of
FIG. 12
;
FIG. 14
illustrates a top plan view of still another alternative form of the present invention;
FIG. 15
is a sectional view taken along line
15
—
15
of
FIG. 14
;
FIG. 16
is a top plan view of still another form of the present invention; and
FIG. 17
is a sectional view taken along line
17
—
17
of
FIG. 16
;
FIG. 18
is a partial longitudinal section of still, another embodiment of the present invention; and
FIG. 19
is a sectional view taken along line
19
—
19
of FIG.
18
.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
While the present invention is susceptible of embodiment in multiple forms, there are shown in the drawings and will hereinafter be described various preferred embodiments of the present invention with the understanding the present disclosure is to be considered as setting forth exemplifications of the invention which are not intended to limit the invention to the specific embodiments illustrated and described.
Referring now to the drawings, wherein like reference numerals indicate like parts throughout the views, there is shown in
FIGS. 1 through 3
an impact tool
10
constructed in accordance with the present invention. The tool illustrated in
FIGS. 1 through 3
for purposes of illustration is in the form of a hammer having exposed striking heads. It should be appreciated, however, the teachings of the present invention are equally applicable to other forms of impact tools such as axes, picks and the like tools.
In the example of the invention shown in
FIGS. 1 through 3
, and as is typical, hammer
10
has a generally T-shaped configuration and includes a head structure
12
with a handle structure
14
extending therefrom and in a generally perpendicular relationship therewith.
The head structure
12
includes first and second independent or separate heads or members
20
and
30
which, in the illustrated form of the invention, are generally axially aligned in a first direction relative to each other. The heads or members
20
,
30
extend toward first and second sides, respectively, of the tool
10
. In one form of the invention, the heads or members
20
,
30
of the head structure
12
are fabricated from a suitable metal or metal alloy. The head or member
20
of head structure
12
defines an exposed striking surface
22
while head or member
30
of head structure
12
defines an exposed striking surface
32
. As will be appreciated, the heads
20
,
30
and the striking surfaces
22
,
32
respectively, could be encased to limit marring of the surface struck or impacted with the tool without detracting or departing from the spirit and scope of the present invention. Moreover, the configurations of the heads or member
20
,
30
of head structure
12
can be other than that shown without departing or detracting from the spirit and scope of the present invention.
The handle structure interconnects the heads
20
,
30
of the head structure
12
to each other and extends in a second direction away from the head structure
12
to provide a generally T-shaped formation or configuration to the tool
10
. The handle structure
14
includes an elongated handle
40
, a lengthwise portion of which extends through and interconnects the heads or members
20
,
30
of the head structure
12
to each other. The handle
40
of handle structure
14
is formed from a class of materials including: wood such as hickory, plastic, metal, nylon, fiberglass, elastomeric, or composite materials. In the illustrated form of the invention, the handle
40
of handle structure
14
is preferably of one-piece construction between opposite ends
42
and
44
thereof to reduce the opportunity of vibrations passing therethrough.
As shown in
FIG. 2
, the head piece or member
20
of the head structure
12
includes a working portion
24
and an attachment portion
26
. Similarly, the head piece or member
30
of the head structure
12
includes a working portion
34
and an attachment portion
36
. Notably, a lengthwise portion of the handle
40
extends through and interconnects the attachment portions
26
,
36
of the heads or members
20
,
30
of the head structure
12
.
The head pieces or members
20
,
30
of the head structure
12
are configured to interconnect relative to each other to prevent their inadvertent separation from each other and from the handle structure
14
during use of the impact tool. To prevent the head pieces or members
20
,
30
from moving beyond a predetermined axial distance or becoming disassociated with the handle structure
14
during use the tool
10
, the attachment sections or portions
26
,
36
are each configured to surround more than a 180′ circumferential segment of the lengthwise portion of the handle
40
extending therethrough. In the illustrated form of the invention, shown in
FIG. 4
, each head piece or member
20
,
30
defines a bore
21
,
31
, respectively, extending therethrough for accommodating endwise reception and holding of a lengthwise portion of the handle
40
.
As shown in
FIGS. 2 and 3
, handle structure
14
furthermore preferably includes a wedge-like insert
16
is driven into the free upper end
42
of the handle
40
passing through the attachment portions
26
,
36
of the heads or members
20
,
30
, respectively, thereby facilitating securement of the head structure
12
to the handle structure
14
. Of course, adhesive or other forms of attachment devices can be used to secure the head structure
12
to the
40
handle structure
14
in addition to the use of a wedge-like member
16
without detracting or departing from the spirit and scope of the present invention.
The head pieces or members
20
,
30
of the head structure
12
are furthermore configured to prevent their axial displacement along the length of the handle
30
. As mentioned, the attachment sections or portions
26
,
36
of the head pieces
20
,
30
, respectively, are each secured to a lengthwise portion of the handle structure
14
extending therethrough. Moreover, the attachment sections
26
,
36
of the heads or members
20
,
30
of the head structure
12
are vertically arranged relative to each other to prevent their inadvertent displacement along the axial length of the handle
40
during operation of the tool
10
.
As shown in
FIGS. 2 and 4
, the attachment portion
26
,
36
of each head piece or member
20
,
30
is configured with an axially extending recess
23
,
33
shaped to complement an axial projection
25
,
35
defined on the heads or members
20
,
30
of the head structure
12
. As will be appreciated, and as shown in
FIG. 2
, when the head pieces or members
20
,
30
of the head structure
12
are assembled relative to each other, the axial projection
25
on the head or member
20
is accommodated within the complementary shaped axially extending recess
33
defined on the head piece or member
30
of head structure
12
. Similarly, and after the head pieces or members
20
,
30
of the head structure
12
are assembled relative to each other, the axial projection
35
on the head or member
30
is accommodated within the complementary shaped axially extending recess
23
defined on the head piece or member
20
of head structure
12
. Since the head pieces
20
,
30
are each secured to a lengthwise portion of the handle structure
14
extending therethrough, the relationship of the projections
25
,
35
coact with the recesses
23
,
33
to prevent displacement of the head pieces or members
20
,
30
relative to each other and along the length of the handle structure
14
even if the securement between the one of the head pieces or members
20
,
30
fails.
According to one salient feature of the present invention, the head pieces or members
20
,
30
of the head structure
12
are axially separated from each other by a predetermined axial distance. As shown in the drawings, the head pieces
20
30
of the head structure
12
are separated from each other in an axial or first direction extending generally perpendicular to the axis of the handle
40
a distance ranging between about 0.010 inches and about 0.070 inches. The distance separating the heads or members
20
,
30
of head structure
12
being substantially exaggerated in the drawings for purposes of explanation.
As shown in
FIGS. 2 and 4
, the head pieces or members
20
,
30
of head structure
12
are provided with complementary and confronting impact surfaces that are axially separated from each other by the predetermined distance mentioned above. In the illustrated form of the invention, an impact surface
27
is provided within the recess
23
on the head piece or member
20
of head structure
12
in spaced and confronting relationship relative to an impact surface
38
on the axial projection
35
of head piece or member
30
of the head structure
12
. Similarly, an impact surface
37
is provided within the recess
33
on the head piece or member
30
of head structure
12
in spaced and confronting relationship relative to impact surface
28
on the axial projection
25
head piece or member
20
of the head structure
12
.
In this, as well as the other illustrated forms of the invention disclosed herein, only one set or pair of complementary confronting impact surfaces necessarily needs to be spaced apart the preferable range of about 0.010 inches to about 0.070 inches. Other confronting impact surfaces defined on the head pieces or members
20
,
30
of the head structure
12
can be spaced a further distance apart from each other without detracting or departing from the spirit and scope of the present invention. As will be appreciated, and as shown, more than one impact surface can be defined on the head pieces or member
20
,
30
of head structure
12
without detracting or departing from the spirit and scope of the present invention as long as the axial spacing between the confronting surfaces is the same.
Another salient feature which distinguishes the present invention from heretofore known tools relates to isolating the two-piece head structure
12
from the handle structure
14
to significantly reduce vibrations transmitted to and through the handle
40
to the user. As shown in
FIGS. 1 through 3
, elastomeric material
50
is provided between the handle structure
14
and the head pieces or members
20
,
30
of the head structure
12
along the lengthwise portion of the handle
40
extending through the head structure
12
. Notably, the elastomeric material
50
, disposed between the head pieces
20
,
30
of the head structure
12
and the handle structure
14
, promotes axial movement of the unstruck head piece toward the head piece that is struck against a surface.
In the illustrated form of the invention, a sleeve
52
formed from an elastomeric material is disposed about and along the lengthwise portion of the handle
40
passing through the head structure
12
. The elastomeric sleeve
52
is secured to that lengthwise portion of the handle structure
14
passing through the head structure
12
and to each of the head pieces or members
20
,
30
of the head structure
12
as by adhesive or the like. As will be appreciated, and in addition to the wedge-like member
16
driven into the free end
42
of the handle
40
, the adhesiveness of the sleeve
52
to the heads or members
20
,
30
and to the handle portion
40
furthermore facilitates maintaining the head structure
12
in operable association with the handle structure
14
.
As will be appreciated by those skilled in the art, the elastomeric material can take a myriad of forms. In the preferred embodiment, an elastomeric composition having a Shore A durometer hardness ranging between about 40 and 95 appears to be best suited for this application.
Another embodiment of a tool embodying features of the present invention is schematically illustrated in
FIGS. 5 and 6
. This alternative form of impact tool is designated generally by reference numeral
110
. The elements of this alternative form of impact tool that are identical to or functionally analogous to those components discussed above regarding impact tool
10
are designated by reference numerals identical to those used above with the exception that this embodiment uses reference numerals in the
100
series.
In this embodiment of the invention, the head structure
112
and handle structure
114
are substantially similar to that discussed above. As mentioned above, the head structure
112
includes a pair of axially separated striking heads
120
,
130
. Moreover, the handle structure
114
includes an elongated handle
140
having opposite ends
142
,
144
.
The head piece or member
130
of the head structure
112
defines a bore
131
extending therethrough and through which a lengthwise portion of the handle structure
114
extends. The head piece or member
120
of the head structure
112
, however, defines a counterbore
121
which accommodates a lengthwise portion of the handle
140
of handle structure
114
. In the embodiment of the invention schematically illustrated in
FIG. 16
, the handle structure
114
furthermore preferably includes a wedge-like insert
116
. As shown, the head piece or member
120
of head completely therethrough. Notably, the counterbore
121
of head piece or member
120
can be structure
112
is provided with an aperture or opening
129
for permitting endwise passage of the wedge-like member therethrough and into the free end of the handle
140
thereby enhancing securement of the head structure
112
and handle structure
114
in operative combination relative to each other.
Notably, the counterbore
121
of the head piece or member
120
and the bore
131
of head piece or member
130
are each configured to accommodate elastomeric material
150
disposed, at least, on opposite sides of the handle structure
114
. As will be appreciated, and as discussed in detail above, the handle structure
114
and/or the elastomeric material
150
can be suitable secured to the head structure as through adhesive or the like.
Another embodiment of a tool embodying features of the present invention is schematically illustrated in FIG.
7
. This alternative form of impact tool is designated generally by reference numeral
210
. The elements of this alternative form of impact tool that are identical to or functionally analogous to those components discussed above regarding impact tool
10
are designated by reference numerals identical to those used above with the exception that this embodiment uses reference numerals in the
200
series.
In this embodiment of the invention, the head structure
212
is substantially similar to that discussed above. As mentioned above, the head structure
212
includes a pair of axially separated striking heads
220
,
230
. The head pieces or members
220
,
230
of the head structure
212
defines bores
221
,
231
, respectively, extending therethrough and through which a lengthwise portion of a handle structure
214
extends to hold the attachment portions
226
,
236
of the head pieces or members
220
,
230
, respectively, together in interconnected relationship relative to each other. Of course, with a simple change the bore
221
of head piece
220
could be configured with a counterbore like head piece
120
discussed above without detracting or departing from the spirit and scope of the present invention.
The handle structure
214
in this embodiment of the invention extends through and holds the head pieces
220
,
230
of the head structure
220
in axially separated relation relative to each other. In this embodiment, the handle structure
214
includes an elongated handle
240
with an enlarged head piece
241
toward that end that passes endwise through the attachment portions
226
,
236
of the head pieces or members
220
,
230
, respectively, of the head structure
212
. In this embodiment of the invention, at least the enlarged head piece
241
of handle structure
214
is formed from an elastomeric composition having a Shore A durometer hardness ranging between about 40 and 95.
The enlarged head piece
241
of handle
240
is sized to snugly fit within bores
221
,
231
defined in the head pieces or members
220
,
230
of the head structure
212
and be secured thereto as with adhesive. The handle structure
214
can further include a wedge-like member (not shown) driven onto the free end thereof, or any other suitable affixation device or method. As discussed above, attachment portions
226
,
236
of the head pieces or members
220
,
230
, respectively, extend at least partially in surrounding circumferential relation relative to a lengthwise portion of the enlarged head piece
242
thereby preventing complete separation of the head pieces or members
220
,
230
from the handle
240
. Although the attachment portions
226
,
236
of the head pieces or members
220
,
230
, respectively, of the head structure
212
appear different than the attachment portions
26
,
36
discussed above regarding head pieces
20
,
30
, they are intended to serve the identical function to that discussed above and are maintained in normally separated relation relative to each other.
Another embodiment of a tool embodying features of the present invention is schematically illustrated in
FIGS. 8 and 9
. This alternative form of impact tool is designated generally by reference numeral
310
. The elements of this alternative form of impact tool that are identical to or functionally analogous to those components discussed above regarding impact tool
10
are designated by reference numerals identical to those used above with the exception that this embodiment uses reference numerals in the
300
series.
In this embodiment of the invention, the tool
310
is configured as a carpentry hammer. The head structure
312
of the hammer
310
includes first and second pieces or members
320
,
330
, respectively, joined to each other by an elongated handle structure
314
extending generally normal to and away from the head structure
312
. The handle structure
314
includes an elongated handle
340
, a lengthwise portion of which extends through and interconnects the heads or members
320
,
330
of the head structure
312
to each other. The handle
340
is preferably formed from a class of materials including: wood such as hickory, plastic, metal, nylon, fiberglass, elastomeric composite materials. The handle
340
is preferably of one-piece construction between opposite ends
342
and
344
thereof. The handle structure
314
furthermore preferably includes a wedge-like structure or insert
316
forced into the upper free end
342
of the one-piece handle
340
of handle structure
314
. The insert
316
of handle structure
314
circumferentially expands that end of handle structure
314
passing, at least partially, through the head structure
312
thereby enhancing the securement of the handle structure
314
to the head structure
312
.
As shown, the first piece
320
of the head structure
212
is configured as a striking head with a striking surface
322
. The other piece or member
330
of the head structure
312
has a claw-like configuration including a pair of laterally spaced tines or members
339
and
339
′ extending away from handle
340
of the handle structure
314
.
To promote axial movement of the heads or members
320
,
330
of the head structure
312
, elastomeric material
350
is inserted between opposed sides of the handle
340
and attachment portions
326
,
336
of the heads or members
320
,
330
, respectively, of the head structure
312
. As will be appreciated, the elastomeric material furthermore isolates the head structure
312
from the handle structure
314
thereby inhibiting vibrations from being transferred along the length of the handle
314
to the user. In the illustrated form of the invention, the elastomeric material
350
is in the form of strips of elastomeric material
352
arranged between opposed lengthwise sides of the handle
340
and the heads
320
,
330
of the head structure
312
.
In this embodiment of the invention, the attachment portions
326
,
336
of the head pieces or members
320
have a clevis-like configuration to enhance distribution of the forces acting on the heads or members
320
,
330
of the head structure
312
. In the embodiment illustrated in
FIG. 9
, the attachment portion
326
of the head piece or member
320
of head structure
312
includes an axially elongated vertically spaced projections
360
. Each axially elongated projection
360
on head piece or member
320
defines an opening or aperture
362
circumferentially extending, at least partially, about a lengthwise section of the handle
340
to hold the striking head
320
to the handle structure
314
. In the illustrated embodiment, the opening
362
defined by the attachment section
326
is sized to fit snugly about the elastomeric material
352
fitted about the handle
340
.
The attachment portion
336
of the head piece or claw-like member
330
of the head structure is configured with a pair of elongated axially extending, vertically spaced projections
370
which, in the illustrated embodiment, are embraced by the projection
360
of head piece or member
320
. The projections
370
of the head piece or claw-like member
330
define a pair of vertically aligned openings or apertures
374
which circumferentially extend, at least partially, about a lengthwise portion of the handle
340
extending endwise therethrough. In the illustrated embodiment, the openings
374
defined by the attachment section
336
of the head piece or claw-like member
330
are sized to fit snugly about the elastomeric material
352
fitted about the handle
353
.
As shown in
FIG. 9
, the striking head
320
of head structure
312
is formed with axially elongated recesses
323
defining vertically aligned impact surfaces
327
for accommodating axial displacement of the attachment portion
336
of the claw-like member
330
there toward. Similarly, the claw-like member or head
330
of the head structure
312
is formed with axially elongated recesses
333
defining impact surfaces
337
.
As shown, each of the axially elongated projections
360
forming part of the attachment portion
326
of the striking head
320
is formed with an impact surface
328
at the distal end thereof Moreover, the axially elongated projections
370
forming part of the attachment portion
336
of the claw-like member
330
of head structure
312
each define vertically aligned impact surfaces
338
at the distal ends of the projections
370
,
372
, respectively.
As shown in
FIG. 9
, when the heads
320
,
330
are assembled relative to each other, the impact surfaces
328
on the head piece or member
320
of the head structure
320
are maintained in a predetermined spaced and confronting relationship relative to the impact surfaces
337
formed on the claw-like member or head
330
. Moreover, when the heads
320
,
330
are assembled relative to each other, the impact surfaces
338
at the distal ends of the projections
370
extending from the claw-like member
330
will be maintained in a predetermined spaced and confronting relationship relative to the impact surfaces
327
formed on the striking head
320
.
Still another embodiment of a tool embodying features of the present invention is illustrated in
FIGS. 10 and 11
. This alternative form of impact tool is designated generally by reference numeral
410
. The elements of this alternative form of impact tool that are identical to or functionally analogous to those components discussed above regarding impact tool
10
are designated by reference numerals identical to those used above with the exception that this embodiment uses reference numerals in the
400
series.
Tool
410
is again configured as a carpentry hammer. The head structure
412
of the hammer
410
includes first and second pieces or members
420
,
430
, respectively. The tool or hammer
410
further includes a handle structure
414
extending from the head structure
412
at a generally perpendicular relationship thereby providing a generally T-shaped configuration to the tool
410
.
As shown, the first piece
420
of the head structure
412
is configured as a striking head with a striking surface
422
. The other member
430
of the head structure
412
is configured with a claw-like design including a pair of laterally spaced tines or members
439
and
439
′.
In this embodiment of the invention, the striking head
420
is preferably of one piece construction and includes a working portion
424
and an attachment portion
426
. The attachment portion
426
of the striking head
420
is specifically configured to be captively received by the claw-like member
430
of the head structure so as to prevent its axial separation therefrom and yet allow a degree of axial movement along a predetermined path relative to the claw-like member or head piece
430
. In the illustrated embodiment, the attachment portion
426
of the striking head
420
is configured with an enlarged end portion
460
to retain the head
420
in captive but axially slidable relationship relative to head piece
430
.
The claw-like member
430
of the head structure
412
has a laminated configuration including first and second halves or pieces
470
,
472
which are the mirror image of each other and, when assembled, provide the entire shape to the claw-like member
430
of the head structure
412
. Each piece
470
,
472
of the claw-like member
430
defines a open sided cavity
473
having a shape corresponding to one half of the attachment portion
426
of the striking head
420
. Moreover, each piece
470
,
472
of the claw-like member
430
defines an open sided channel
474
conforming to one-half of the cross-sectional configuration of the lengthwise portion of the one-piece handle
440
extending endwise therethrough.
In the illustrated form of the invention, and as made possible by the laminated structure of the head piece
430
, the attachment portion
426
of the head piece
420
is captively received within a recess formed by the abutting cavities
473
defined by the pieces
470
,
472
of the head piece
430
of the head structure
412
while the handle
440
forming handle structure
414
extends only through the head piece or claw member
430
of the head structure
412
. The laminations
470
,
472
forming the claw-like member
430
of the head structure
412
are fixedly held to each other as by a series or plurality of rivets
480
or other suitable securement devices.
As shown, the handle
440
has a changing cross-sectional configuration along that lengthwise portion extending through the claw-like member
430
of the head structure. The changing cross-sectional configuration of the handle
440
is specifically configured to secure the claw-like member
430
along the length of the handle structure
414
. In the illustrated embodiment of the invention, a generally centralized lengthwise section of the handle
440
has a reduced outer configuration from those lengthwise sections of the handle
440
arranged adjacent upper and lower sides of the claw-like member
430
. Accordingly, the handle
440
is prevented from axially moving along its length relative to the claw-like member. Of course, configurations other than that exemplified may equally suffice without detracting or departing from the scope of the present invention. Notably, however, the laminated or lengthwise split configuration of the member
430
allows such a design to capture the handle structure
414
relative to the head structure
412
. Moreover, in the illustrated form of the invention, the handle
440
has a cross-sectional configuration which inhibits the handle
440
from rotating or turning relative to the head piece
430
. Furthermore, and to inhibit vibrations from transferring along the length of the handle structure, the handle
440
is preferably configured as a one-piece member.
To further reduce vibrations from being transmitted along the length of the handle structure, elastomeric material
450
is inserted between the lengthwise portion of the handle
440
and the that portion of head piece
430
arranged in surrounding relationship thereto. As will be appreciated, the elastomeric material
450
only needs to be positioned on opposite sides of the handle
440
to promote axial movements of the head pieces
420
,
430
toward each other. In the illustrated form of the invention, however, a sleeve
452
of elastomeric material is positioned along and about the lengthwise portion of the handle
440
extending through the head piece
430
of the head structure
412
. The elastomeric material has a hardness ranging between about a Shore A durometer hardness and about a 95 Shore A durometer hardness.
As shown in
FIGS. 10 and 11
, the attachment portion
426
of the head piece or striking head
420
of the head structure
412
is configured with an elongated shank-like projection axially extending from the striking head
420
with an impact surface
428
at a distal end thereof Moreover, the claw-like member
430
is configured with a recess
433
shaped to accommodate the shank-like projection
426
on the head piece or member
420
. Notably, an impact surface
427
is defined by the recess
473
. As will be appreciated, when the heads
420
,
430
are assembled relative to each other, the impact surface
428
on the striking head
420
and the impact surface
437
on the claw-like member
430
are in confronting but axially spaced relation relative to each other. The axial spacing having a predetermined distance therebetween. In the illustrated embodiment, an elastomeric material
481
is positioned between the impact surface
428
on the head or member
420
and the impact surface
437
on the claw-like member
430
to act as a spring for maintaining the axially spaced relationship between the confronting impact surfaces defined by the head or members
420
,
430
of the head structure
412
.
FIGS. 12 and 13
illustrate an alternative embodiment of the invention substantially similar to that illustrated in
FIGS. 10 and 11
. This embodiment of the invention includes substantially the same structure as discussed above regarding tool
410
with the exception of the manner by which the striking head
420
is secured to the claw-like member
430
. In this embodiment of the invention, the attachment portion
426
on the striking head
420
is configured as an axially elongated shank-like projection axially extending away from the striking head
420
and is slidably received for axial movement within a cavity
433
defined by the head piece or claw-like member
430
. That is, and with this embodiment of the hammer
410
, the axially extended projection
426
is arranged for endwise or axial sliding movement within the recess
433
in the claw-like member
430
defined by the two abutting laminations
470
,
472
.
As mentioned above, in this embodiment of the invention, a series of rivets or other suitable fasteners
480
serve to fixedly hold the laminations
470
,
472
to each other. In the illustrated form of the invention, the rivets or fasteners
480
are shown as extending through the laminations
470
,
472
and holding them in fixed relation relative to each other it will be appreciated by those skilled in the art, however, the fasteners do not necessary need to extend completely through both laminations
470
,
472
. Other alternative means of securing the laminations
470
,
472
to each other would equally suffice without detracting or departing from the novel spirit and scope of the present invention. In the illustrated form of the invention shown in
FIGS. 12 and 13
, at least one elongated fastener
480
axially extends through the shank-like axial projection on head piece
420
. The axially elongated projection
426
is provided with a throughbore
482
having a diameter greater than the diameter of the rivet or fastener
480
used to hold the laminations
470
,
472
in assembled relation relative to each other. As shown in the drawings, a bearing sleeve of elastomeric material
484
fills the void around the rivet or fastener
480
and the internal diameter of the bore
482
. The elastomeric material will have generally the same characteristics as mentioned above and will serve to maintain the impact surfaces
437
and
428
on the head members or pieces
420
and
430
of the head structure in predetermined axially spaced relation relative to each other while also allowing for the impact surfaces to collide with each other when the striking head
420
is stricken against a surface or object.
A further embodiment of a tool embodying features of the present invention are schematically illustrated in
FIGS. 14 and 15
. This alternative form of impact tool is designated generally by reference numeral
510
. The elements of this alternative form of impact tool that are identical to or functionally analogous to those components discussed above regarding impact tool
10
are designated by reference numerals identical to those used above with the exception that this embodiment uses reference numerals in the
500
series.
Tool
510
is similar in configuration to the tool
10
discussed above and shown in
FIGS. 1 through 3
. In this embodiment of the invention, the tool
510
includes a head structure
512
including first and second pieces or members
520
and
530
, respectively, which are axially aligned in a first direction. The tool or hammer
510
further includes a handle structure
514
extending from the head structure
512
in a second direction and generally perpendicular to the head structure
512
thereby providing a generally T-shaped configuration to the tool
510
.
The head pieces or members
520
and
530
of the head structure
512
are each formed from a series of laminations
529
and
539
, respectively, fixedly held to each other by a series of suitable rivets or fasteners
580
. Each plate or lamination
529
forming the head piece or member
520
is configured with a cutout
522
which, after the plates
529
are assembled relative to each other, define a recess
523
including at least one impact surface
527
. Moreover, each lamination or plate
529
of the head member or piece
520
has an extension
526
having an impact surface
528
at a distal end thereof. Each plate or lamination
539
forming the head piece or member
520
is configured with a cutout
532
which, after the plates
539
are assembled relative to each other, define a recess
533
including at least one impact surface
537
. Moreover, each lamination or plate
539
of the head member or piece
530
has an extension
536
having an impact surface
538
at a distal end thereof. Notably, when the laminated head pieces
520
,
530
are assembled relative to each other, the impact surfaces
527
,
538
and
537
,
528
, respectively, are arranged in confronting but predetermined spaced relationship relative to each other in substantially the same manner as discussed above.
In this embodiment of the invention, one each of the laminated plates
529
,
539
forming the laminated head pieces
520
,
530
of the head structure
512
is formed like the other except that one each of the plated
529
,
539
is sufficiently sized to permit a bore
521
,
531
to be provided therein for allowing a lengthwise portion of the handle structure
514
to extend endwise therethrough. As described above, the handle structure
514
furthermore preferably includes a suitably shaped member, such as a wedge-like member
516
, which is driven into or operative extends from the free end
542
of the handle
540
of handle structure
514
to facilitate securement of the head structure
512
to the handle structure
514
.
Such that either end of the head structure
512
can be used for striking purposes, a cap structure
570
fits about the ends of the laminations
529
,
539
of the heads or members
520
,
530
of the head structure
512
. As will be appreciated, the cap structure
570
defines a striking surface
525
,
535
for each head or member
520
,
530
of the head structure
512
. In the illustrated form of the invention, each cap structure
570
defines a peripheral wall or skirt
527
arranged in capturing and surrounding relation relative to the laminations
529
,
539
of the head or members
520
,
530
thereby inhibiting the laminations
529
,
539
from “separating” relative to each other as the tool
510
is used to strike a surface. The cap structure
570
is secured as through any suitable means to the ends of the laminations
529
,
539
forming the heads or members
520
,
530
of the head structure
512
. It is also within the scope of the present invention to configure the head structure of the impact tool
510
such that alternating laminations can be formed from an elastomeric material.
A still further embodiment of a tool embodying features of the present invention are schematically illustrated in
FIGS. 16 and 17
. This alternative form of impact tool is designated generally by reference numeral
610
. The elements of this alternative form of impact tool that are identical to or functionally analogous to those components discussed above regarding impact tool
10
are designated by reference numerals identical to those used above with the exception that this embodiment uses reference numerals in the
500
series.
The tool
610
is similar in configuration to the laminated tool
510
discussed above and shown in
FIGS. 14 and 15
. In this embodiment of the invention, the tool
610
includes a head structure
612
including first and second pieces or members
620
and
630
, respectively, which are axially aligned in a first direction. The tool or hammer
610
further includes a handle structure
614
extending from the head structure
612
in a second direction and generally perpendicular to the head structure
612
thereby providing a generally T-shaped configuration to the tool
610
.
The head pieces or members
620
and
630
of the head structure
612
are each formed from laminations
621
and
631
, respectively, fixedly held to each other by a series of suitable rivets or fasteners
680
. To reduce vibration transmission through the handle structure
614
and to allow the head pieces
620
,
630
of the head structure
612
to collide relative to each other, at least one other lamination
625
formed from an elastomeric material is sandwiched or inserted between the laminations
621
and
631
forming the head pieces or member
620
,
630
and is secured to each by the fasteners
680
.
The laminations
621
,
631
each define an impact surface
627
,
638
and
628
,
637
, respectively, arranged thereon. The impact surfaces
627
,
638
and
637
,
628
, respectively, on the laminations
621
,
631
forming the head pieces or members
620
,
630
of head structure
612
are arranged in confronting axially spaced relation relative to each other.
As shown, the handle structure
614
includes a one-piece handle
640
have a changing cross-sectional configuration along that lengthwise portion extending endwise through the elastomeric lamination
625
of the head structure
612
. The changing cross-sectional configuration of the handle
640
is specifically configured to secure the elastomeric lamination
625
along the length of the handle structure
614
. As shown, the lengthwise section of the handle
640
arranged in operative association with the head structure
612
preferably has an hourglass configuration. Accordingly, the handle
640
is prevented from axially moving along its length relative to the laminations
625
and, thus, relative to head structure
612
. Of course, configurations other than that exemplified may equally suffice without detracting or departing from the scope of the present invention. Notably, however, the laminated or lengthwise split configuration of the head structure
612
allows such a design to capture the handle structure
614
relative to the head structure
612
.
FIGS. 18 and 19
schematically illustrate still another embodiment of an impact tool embodying salient features of the present invention. This alternative form of impact tool is designated generally by reference numeral
710
. The elements of this alternative form of impact tool that are identical to or functionally analogous to those components discussed above regarding impact tool
10
are designated by reference numerals identical to those used above with the exception that this embodiment uses reference numerals in the
700
series.
Tool
710
is again configured as a carpentry hammer. The hammer
710
includes a head structure
712
and an elongated handle structure
714
extending generally normal to the head structure
712
. One of the salient features involving this embodiment of the invention concerns the composite structure of the hammer
710
. That is, in this embodiment of the invention, a skin or sock
702
extends about and along at least that lengthwise portion of the handle structure
714
extending into operative cooperation with the head structure.
In a preferred form of the invention, the skin
702
is fabricated from an arimid fiber material such as KEVLAR® marketed and sold by the DuPont Corporation. The arimid fiber material used in combination with the present invention has a unique combination of high strength, high modulus and toughness. The arimid fiber material or skin
702
is encapsulated or impregnated into an epoxy such as that sold and marketed by Ad-Tech as CER-
112
. This aspect of the present invention takes advantage of the natural tendency of the free ends of woven or braided fiber to fray and expand. As will be appreciated, and after the epoxy solidifies and hardens about the woven fabric or skin
702
, the epoxy impregnated into the fiber sleeve maintains the frayed ends of the sleeve
702
in a radially expanded configuration, as schematically illustrated in
FIG. 18
, and thereby enhances the interface between the head structure
712
and the handle structure
714
while furthermore preventing the handle structure
714
from pulling out or separating from the head structure
712
.
In one form, a cover
704
is disposed along and about a lengthwise portion of the handle structure
714
disposed beneath and in combination with the head structure
712
. The purpose of the cover
704
is to extend about a lengthwise portion of the epoxied and impregnated fiber material extending beyond the head structure
712
of the tool
710
. To maintain the distinctive character of the tool
710
, however, at least a lengthwise portion of the cover
704
is transparent or otherwise visually permeable to permit visual access to the material skin
702
while inhibiting inadvertent unwrapping or unraveling of the impregnated fiber skin
702
.
In that form illustrated in
FIGS. 18 and 19
, head structure
712
includes first and second pieces or members
720
and
730
, respectively. The members or pieces
720
,
730
of head structure
712
are joined by the elongated handle structure
714
extending, at least partially, therethrough.
As shown, the first member or piece
720
of head structure
712
is configured as a striking head with a striling surface
722
. In the illustrated embodiment of the invention, the other piece or member
730
of the head structure
712
has a claw-like configuration including a pair of laterally spaced tines or members
739
and
739
′.
In the illustrated form of the invention, and as made possible by the two-piece split head design, the head piece
720
includes an attachment portion
726
projecting away from and generally normal to the striking surface
722
. The head piece
730
likewise includes an attachment portion
736
defining an elongated opening
773
for endwise receiving the attachment portion
726
of head piece or member
720
. Notably, the opening
773
allows for radial expansion of the frayed free ends of the sock
702
in the manner described above. In the illustrated embodiment, the attachment portion
726
of head piece or member
720
has a generally semi-circular configuration extending axially away from the distal end of member
720
arranged opposite from the striking surface
722
to provide further space for expansion of the free ends of the braided sock
702
. Moreover, the distal end of the attachment portion
726
of head piece or member
720
defines an impact surface
728
arranged in confronting but spaced relationship to an impact surface
738
defined by an end wall of the elongated recess or opening
773
defined by head member or piece
730
. The confronting impact surfaces
728
,
738
on the heads
720
,
730
, respectively, are spaced from reach other in the same relationship described above to advantageously yield a dead-blow characteristic to the hammer
710
.
As shown in
FIGS. 18 and 19
, the attachment portion
726
of head piece or member
720
further defines an open ended recess or opening
727
extending therethrough. Similarly, the attachment portion
736
of the head piece
730
defines a throughbore or opening
737
for accommodating the handle structure
714
and which opens to an upper surface of the head piece or member
730
of head structure
712
. Notably, when the split head pieces or members
720
and
730
of head structure
712
are arranged in operative relationship relative to each other, as shown in
FIGS. 18 and 19
, the openings or recesses
727
and
737
defined by the attachment portions
726
and
736
of the head members
720
and
730
, respectively, of head structure
712
are in general registry with one another.
A lengthwise portion of handle structure
714
of tool
710
extends through the head pieces or members
620
,
730
of head structure
712
thereby joining them in operative combination relative to each other. In the embodiment of the invention schematically illustrated in
FIGS. 187 and 19
, handle structure
714
includes an elongated handle
740
, a member
716
extending endwise from that end of the handle
740
extending into the head structure
712
, and an elastomeric link
750
which operatively acts as a lengthwise extension of that portion of the handle
740
inserted into the head structure
712
.
The handle
740
of the handle structure
714
is preferably formed from a class of materials including: woods, such as hickory; plastic; metal; nylon; fiberglass; or other suitable rigid material. The handle
740
has opposed ends
742
and
744
. As shown in
FIGS. 18 and 19
, the end
742
of handle
740
is configured for insertion within the head structure
712
of the tool. In this regard, and to enhance its insertion within the head structure
712
, the end
742
of handle
740
preferably has an inwardly tapered configuration.
In the illustrated form of the invention, member
716
of the handle structure
714
has a generally wedge-like configuration but any suitable design would equally suffice without detracting or departing from the spirit and scope of the present invention. For example, a screw threaded into the free end
742
of the handle
740
would equally apply. Notably, member
716
axially extends from and is secured to the free end
742
of handle
740
of handle structure
714
. Moreover, the member
716
projects endwise through the openings
727
and
737
defined by the attachment portions
726
and
736
, respectively, of the heads or pieces
720
,
730
forming the head structure
712
.
To further reduce vibrations from being transmitted along the handle structure
714
during use of the tool
710
, handle structure
714
further includes the elastomeric link
750
for resiliently joining the head pieces or member's
720
,
730
of the head structure
712
to each other and to handle structure
714
. The elastomeric link
750
has a durometer hardness ranging between about 40 Shore A durometer hardness and about a 95 Shore A durometer hardness. As will be appreciated from an understanding of the present invention, the elastomeric link
750
acts as a spring for returning the nonstruck head of the head structure
712
to a normal or operational position after moving toward and impacting with the struck head or member of the head structure
712
. Accordingly, any suitable material which, during use of the tool
710
, will initially compress and subsequently return the unstruck head piece or member to an operational position relative to the struck head after the struck head has impacted with a surface will suffice.
Assembly of the impact tool
710
illustrated in
FIGS. 18 and 19
preferably involves the following steps and processes. The free end
742
of handle
740
, with the arimid sock to sleeve
702
arranged thereabout, is inserted into the head piece
730
of head structure
712
. The attachment portion
726
of head piece
720
is then inserted into the opening
773
and into operative relationship with the head member
730
. The epoxy or adhesive is the introduced through the openings
727
and
737
of the head pieces
720
,
730
, respectively, to impregnate and wet the arimid fiber sleeve
702
thereby enhancing the securement between the head structure
712
and handle structure
714
interface. Thereafter, member
716
of handle structure
714
is inserted into operative association with the free end
742
of handle
740
thereby causing outward radial expansion of the free end
742
of handle
740
and thereby further enhancing the securement between the head structure
712
and handle structure
714
interface. Next, an elastomer, such as polyurethane, is inserted or injected into the openings
727
and
737
of the head pieces
720
and
730
, respectively, to completely fill the voids and surround that portion of member
716
extending axially from the handle
740
. As will be appreciated, and when solidified, the polyurethane acts as the elastomeric link
750
joining the head pieces or members
720
,
730
of head structure to each other and to handle
740
.
The cover
704
can be arranged about the handle
740
of handle structure
714
prior to insertion of the handle
740
into operative association with the head structure
712
. After the head structure
712
and handle structure
714
are fixed to each other, the cover
704
is slidably moved into the position illustrated in
FIGS. 18 and 19
relative to the head structure
712
. Alternatively, and in a manner well known in the art, the cover
704
can be molded about the handle
740
of handle structure
714
after the head structure
712
and handle structure
714
are arranged in operative association relative to each other.
The split head impact tool described above has several advantages over heretofore known impact tools. Unlike other impact tools, the heads or members of the head structure of the present invention are formed separate from each other. As will be appreciated, separately forming the heads or members of the head structure facilitates interchangability and significantly simplifies the manufacturing process. Rather than having to forge an entire head assembly for a impact tool, various manufacturing methods or processes can be used to fabricate the heads or member so the head structure of then present invention in the most economical fashion possible. For example, the separate heads or members of the head structure may be individually forged, cast, or they can be formed as laminated formations depending on which manufacturing process best serves the manufacturers needs.
Unlike heretofore known impact tools, the separate heads of the head structure of the present invention are interconnected to each other by the handle structure of the tool extending therethrough. In a preferred form of the present invention, each head or member of the head structure includes a working end or portion and an attachment portion. The attachments portions or ends of the heads or members of the head structure are interconnected to each other by the handle extending therethrough in a manner heretofore unknown.
The split head design of the present invention advantageously offers a unique “dead blow” characteristic during use of the impact tool. This dead blow characteristic is enhanced when elastomeric material is provided between the heads and opposite sides of the handle structure. The elastomeric material between the heads and the handle structure serves to maintain impact surfaces defined by the heads of the head structure in a predetermined spaced relationship relative to each other. The predetermined spacing between the impact surfaces on the heads or members of the head structure ranges between about 0.010 inches and about 0.070 inches. The spacing between the heads of the head structure is dependent upon a number of factors including: mass distribution or the head configurations; the hardness of the elastomeric material between the heads and the handle structure; the time of the collision between the impact surfaces; the length of time the striking head of the head structure remains in contact with the struck surface; and, whether the struck surface is stationary or movable. These are a few of the considerations for setting the spacing between the heads of the head structure.
The separated head design offered by the present invention allows the unstruck head of the head structure to act as a lagging mass that suppresses the rebound of the struck head. That is, the split heads of the head structure of the present invention are permitted to axially move along a predetermined path relative to each other such that when one head of the head structure is impacted on a surface of an object, the other head of the head structure moves toward and collides with the struck head thereby providing a secondary blow keeping the struck head from rebounding and, thus, deadening the blow of the hammer or impact tool. Moreover, the elastomeric material between the head structure and the handle structure serves to isolate the handle from the heads or members of the head structure, thus, significantly reducing the vibrations transferred along the handle to the user.
The alternative laminated structure for the heads of the head structure furthermore allows one head of the head structure to be captured by the other head of the head structure to further simplify the present invention. End caps define a striking surface for the head structure of the tool and inhibits “splitting” of the laminations during use of the tool.
As will be appreciated by those skilled in the art, the composite structure of such an impact tool design offers several advantages regardless of whether the head structure embodies a split head design or is of unitary construction. First, using the arimid fiber material in combination with an epoxy offers increased strength between the head structure and handle structure interface. Second, such a composite structure isolates the head structure
712
from the handle structure
714
. Moreover, and because the skin
702
and epoxy add layers about that portion of the handle structure
714
passing into operative combination with the head structure
712
of the tool
710
, a more complex and complicated path needs to be traversed by the vibrations when the head structure
712
is struck against a surface. As will be appreciated, the more complicated path for vibrations to travel between the struck head and the handle advantageously yields vibration dampening characteristics during use of the tool
710
. Moreover, should a portion of the material skin or sock
702
extend beyond the head structure
712
and along a portion of the handle structure
714
, its appearance will undoubtedly add distinctiveness to the hammer design.
From the foregoing it will be observed that numerous modifications and variations can be effected without departing or,detracting from the true spirit and scope of the novel concept of the present invention. It will be appreciated that the present disclosure is intended to set forth exemplifications of the invention which are not intended to limit the invention to the specific embodiments illustrated. The disclosure is intended to cover by the appended claims all such modifications as fall within the spirit and scope of the claims.
Claims
- 1. A hammer, comprising:a head assembly including first and second members, each member of said head assembly including a working portion and an integral attachment portion, and wherein the attachment portions of said members extend to opposite sides of a longitudinal axis defined by a handle structure; and with said handle structure extending generally perpendicular to and through the attachment portions of said first and second members thereby operably interconnecting said first and second members of said head assembly to each other; and an elastomer arranged in operable association with said handle structure and the attachment portions of the first and second members of said head assembly such that confronting and spaced impact surfaces defined on said first and second members of said head assembly are maintained in spaced relation relative to each other by a predetermined distance measuring between about 0.010 inches and about 0.070 inches.
- 2. A hammer, comprising:a head assembly including first and second members, each member of said head assembly including a working portion and an attachment portion, with the attachment portion of each member extending to opposite lateral sides of an elongated axis defined by a handle structure; wherein said handle structure passes through and is secured to the attachment portions of said first and second members of said head assembly thereby limiting movement of the first and second members of said head assembly relative to the longitudinal axis of said handle structure, with said handle structure including an elongated handle extending generally perpendicular from said head assembly; and an elastomeric member arranged in operable association with the handle structure and said attachment portions of said first and second members.
- 3. The hammer according to claim 2 wherein said members of said head assembly are metal.
- 4. The hammer according to claim 2 wherein at least one of said members includes an exposed metal striking surface.
- 5. The hammer according to claim 2 wherein one of said members is configured as a striking head while the other member is configured as a claw.
- 6. The hammer according to claim 2 wherein said elastomeric member is formed from a urethane material having a durometer hardness ranging between about a 40 and about a 95 Shore A hardness.
- 7. An impact tool, comprisinga head assembly including first and second members, each member of said head assembly including a working portion and an attachment portion, and wherein each member of said head assembly further includes an impact surface arranged in axially spaced but confronting relation to an impact surface on the other member; handle structure defining an elongated axis, with said handle structure passing through and secured to the attachment portions of the first and second members extending to opposite sides of said axis thereby interconnecting said first and second members to each other; and elastomeric material disposed in operable association with said first and second members of said head assembly for maintaining said impact surfaces in predetermined spaced relation relative to each other, said elastomeric material acting as a dampener such that when one member of said head assembly is struck against a surface the unstruck member moves toward the struck member to provide a force that inhibits the struck member from bouncing from the surface and such that rebound of the impact tool is significantly reduced.
- 8. The impact tool according to claim 7 wherein at least one of the members of said head assembly has an exposed metal striking surface.
- 9. The impact tool according to claim 7 wherein one of the members of said head assembly is configured as a striking head while the other member of said head assembly is formed as a claw.
- 10. The impact tool according to claim 7 wherein the attachment portion of each member of the head assembly is arranged in surrounding relation relative to a lengthwise portion of said handle structure.
- 11. The impact tool according to claim 7 wherein the axial spacing between the confronting surfaces of the members of said head assembly measures approximately 0.010 inches to about 0.070 inches.
- 12. The impact tool according to claim 7 wherein both members of said head assembly are metal, and wherein said elastomeric member has a durometer hardness ranging between about 60 and about 95 Shore A hardness.
- 13. The impact tool according to claim 7 wherein said handle is formed from a class of materials including: wood, plastic, metal, nylon, fiberglass, or elastomers.
- 14. A generally T-shaped hammer, comprising:a head assembly including first and second heads, with said first head extending in a first direction and defining a striking surface thereon, said first head including an attachment portion extending away from said striking surface and to one side of an elongated axis, and with said second head extending in a second direction opposed to said first direction, said second head including an attachment portion extending to an opposite side of said elongated axis; handle structure extending generally normal to said first and second directions, said handle structure including an elongated handle whose longitudinal centerline defines said elongated axis, with a lengthwise section of said handle structure extending into operative association with the first and second heads and said head assembly thereby maintaining said heads in operable association relative to each other; elastomer material arranged in operative association with said first and second heads for maintaining confronting impact surfaces defined by said heads in a predetermined spaced relationship relative to each other; and a woven fiber material disposed about and epoxied to a lengthwise section of said handle structure extending into operative association with said head assembly to enhance the interface therebetween while adding strength to the hammer.
- 15. The hammer according to claim 14 wherein said woven fiber comprises an arimid fiber.
- 16. A shock absorbing claw hammer, comprising:a handle defining an elongated axis; and a head structure arranged in combination with and disposed at one end of said handle, said head structure including a striking head portion and a claw portion extending opposite from said striking head portion and defining a slit therebetween which opens to an exterior of said head structure, and wherein the striking head portion and the claw portion define confronting impact surfaces which are spaced a predetermined distance apart from each other, and wherein the head structure and handle combination is configured such that the impact surfaces are disposed to one side of the elongated axis with the spacing between said confronting impact surfaces collapsing upon a hammer strike thereby substantially eliminating vibrations in the handle resulting from the hammer strike.
- 17. The claw hammer according to claim 16 wherein said handle comprises part of a handle structure, and wherein said handle structure and said head structure comprise individual pieces.
- 18. The claw hammer according to claim 16 wherein said striking head portion and said claw portion comprise individual pieces.
- 19. The claw hammer according to claim 17 wherein said striking head portion and said claw portion of said head structure each include attachment portions, and wherein at least a lengthwise portion of said handle structure extends endwise through the attachment portions of said head portion and said claw portion.
- 20. The claw hammer according to claim 16 wherein the predetermined spacing maintained between the confronting impact surfaces of said striking head portion and said claw portion of said hammer ranges between about 0.010 inches and about 0.70 inches.
- 21. A shock absorbing claw hammer, comprising:an elongated handle defining an elongated axis and having opposed sides; and a head structure arranged in combination with one end of said handle, said head structure including a striking head portion and a claw portion extending opposite from said striking head portion, and wherein the striking head portion and the claw portion define confronting impact surfaces, and wherein the head structure and handle combination is configured such that the impact surfaces are outwardly disposed to one side of the elongated axis and outwardly from opposed sides of said handle, and with a predetermined spaced relationship between said impact surfaces being maintained by an elastomer disposed within the head structure and which allows the spacing between the confronting impact surfaces to collapse other upon a hammer strike thereby substantially eliminating vibrations in the handle resulting from the hammer strike.
- 22. The claw hammer according to claim 21 wherein said handle comprises part of a handle structure, and wherein said handle structure and said head structure comprise individual pieces.
- 23. The claw hammer according to claim 22 wherein said striking head portion and said claw portion of said head structure each include attachment portions, and wherein at least a lengthwise portion of said handle extends endwise through the attachment portions of said head portion and said claw portion.
- 24. The claw hammer according to claim 21 wherein said striking head portion and said claw portion comprise individual pieces.
- 25. The claw hammer according to claim 21 wherein the predetermined spacing maintained between the confronting impact surfaces of said striking head portion and said claw portion of said hammer ranges between about 0.010 inches and about 0.70 inches.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/US98/07479 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO98/48978 |
11/5/1998 |
WO |
A |
US Referenced Citations (22)
Foreign Referenced Citations (1)
Number |
Date |
Country |
412030 |
Feb 1991 |
EP |