Note: Descriptions are shown in the official language in which they were submitted.
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DUAL MULTI-BIT SCREWDRIVER
TECHNICAL FIELD
The present invention relates to a dual
screwdriver wherein the handle is made of two sections with
the rear section being disconnectable from the front section
and constituting a stub screwdriver. In particular the two
handle sections are interconnected in clamping function fit
and a storage magazine is provided about the periphery of
1o the rear wall of the front handle section by cavities having
at least a portion thereof formed of a thermoplastic
elastomer section which forms part of the handle to provide
improved retention of the bits while providing improved
torquing by the hand of a user.
BACKGROUND ART
Multi-bit screwdrivers are known wherein the bits
are stored within the handle of the screwdriver and are
accessible by disconnecting a portion of the handle. An
2o example of such multi-bit screwdrivers is shown and
described in U.S. Patent 4,552,044. With such screwdrivers,
it is necessary to change the screwdriver bit every time the
screw head has a different shape. Also with such
screwdrivers the handle is of a common size and when working
z5 in a restricted space that type of screwdriver may not be
usable.
Dual screwdrivers having a main screwdriver handle
and a disconnectable stub end which is convertable to a stub
screwdriver is also known as described in U.S. Patent
30 5,868,048. This particular patent describes a specific
system of interlocking the stub end handle section to the
main handle section and the bits are merely retained in a
loose arrangement in a hollow section of the handle.
Accordingly, these bits are easily lost and only a limited
35 amount of bits can be accommodated.
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U.S. Patent 5,881,615 describes a multi-bit
screwdriver wherein bits are secured about the outside of
the handle in grooves which are sized and shaped to receive
a single bit. The bits have opposed screw engaging heads
s and are retained in the grooves by sliding panels slidingly
connected to the handle. The panels only cover a portion of
these grooves. Accordingly, when a person grasps the
handle, his hand is exposed to irregularities which makes it
very uncomfortable. Also, during the torquing application
io of the handle, stress is imposed upon these sliding panels
which can often break. The panels also break when the
screwdriver is dropped on a hard surface. Another
disadvantage of such screwdriver handles is that the sliding
panels may be accidentally displaced thereby accidentally
~s releasing a bit. Also, if one of these sliding panels
break, then the groove is no longer useable and the grasping
of the handle is rendered even more uncomfortable to the
user' s hand and without storage space the loose bit becomes
lost and the utility of the screwdriver is impaired.
zo
SUMMARY OF INVENTION
It is a feature of the present invention to
provide a dual multi-bit screwdriver which substantially
overcomes the above-mentioned disadvantages of multi-bit and
z5 dual-type screwdrivers of the prior art.
Another feature of the present invention is to
provide a dual multi-bit screwdriver wherein the handle is
made of two sections and wherein the sections can separate
from one another to form two screwdrivers having handles and
3o shafts of different lengths.
Another feature of the present invention is to
provide a dual multi-bit screwdriver having a two section
handle and wherein the sections are disconnectable from one
another by exerting a pulling force and wherein when
35 disconnected provide access to a screwdriver bit magazine
protected by the stub handle section.
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Another feature of the present invention is to
provide a dual screwdriver having a multi-bit capability.
Another feature of the present invention is to
provide a dual multi-bit screwdriver wherein the screwdriver
s bit magazine has at least a section thereof provided with a
pliable thermoplastic elastomer to provide frictional
retention against the bit and wherein the thermoplastic
elastomer also extends in the outer handle surface to
provide improved friction retention with the hand of a user
~o person to improve torquing the torque transmitting shaft of
the main screwdriver body and the stub screwdriver body.
According to the above features, from a broad
aspect, the present invention provides a dual multi-bit
screwdriver which comprises a handle having a front and a
rear handle section removably interconnected together. An
elongated torque transmitting shaft extends axially from a
front end of the front handle section. The rear handle
section has a short torque transmitting shaft extending
axially from a front end thereof and extending within a
zo central inner bore of the front handle section when the rear
handle section is mated with the front handle section. Each
of the torque transmitting shafts have a chuck cavity at a
free end thereof for receiving a screwdriver bit in close
friction fit therein. A bit storing magazine is formed in a
z5 rear wall of the front handle section and extends about the
handle for storing a plurality of spaced-apart screwdriver
bits in friction fit retention therein with an end portion
of the bits projecting from the magazine sufficiently for
removal by finger engagement. The rear handle section has
3o cavity means to receive projection portions of the bits
stored in the magazine when the rear handle section is mated
with the front handle section.
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BRIEF DESCRIPTION OF DRAWINGS
A preferred embodiment of the present invention
will now be described with reference to the accompanying
drawings in which:
s FIG. 1 is a perspective view showing the dual
multi-bit screwdriver of the present invention;
FIG. 2 is a side view of the dual multi-bit
screwdriver of the present invention showing the two handle
sections separated from one another whereby to constitute
~o two screwdrivers;
FIG. 3 is a sectional side view of the dual
multi-bit screwdriver with the handle sections mated with
one another;
FIG. 4 is an end view showing a modified
configuration of the screwdriver bit storage magazine;
FIG. 5 is a view similar to Figure 4 showing the
configuration of the screwdriver bit storage magazine of the
screwdriver embodiment described herein;
FIG. 6 is an enlarged section view showing the
zo friction projection made in the thermoplastic elastomer
portion which projects into the cylindrical cavities of the
bit storing magazine;
FIG. 7 is a side view showing the construction
of the front handle section;
2s FIG. 8 is a section view of the handle section
along cross-section lines A-A of Figure 5;
FIG. 9 is a side view of the rear handle
section;
FIG. 10 is an inner end view of the rear handle
3o section shown in Figure 9; and
FIG. 11 is a section view along cross-section
lines B-B of Figure 10.
DESCRIPTION OF PREFERRED EMBODIMENTS
35 Referring now to the drawings and more
particularly to Figures 1 and 2, there is shown generally at
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the dual mufti-bit screwdriver of the present invention.
The screwdriver has a handle 11 which is comprised of a
front handle section 12 and a rear handle section 13 which
are mated in frictional clamping retention with one another.
s An elongated bit receiving torque transmitting shaft 14
extends axially from the front end 15 of the front handle
section 12.
As shown in Figure 2, when the rear handle section
13 is separated from its clamping friction fit with the
~o front handle section 12, the rear handle section 13
constitutes a stub screwdriver and it is also provided with
a short bit receiving torque transmitting shaft 16 extending
axially from the front end 17 thereof. As hereinshown a
screwdriver bit 18 is received within a chuck cavity 19 (see
Figure 3) formed at opposed free ends of the shaft 14.
Similarly, as shown in Figure 3, the front end of the short
bit receiving shaft 16 of the rear handle section 13 is
provided with a chuck receiving cavity 20 to also receive in
close removable fit therein a screwdriver bit 18. The
2o shafts 14 and 16 are provided with an annular groove 14' and
16', respectively, in their bit receiving chuck cavities 19
and 20. A spring bias bearing (not shown) is provided in
the bits 18 to engage with the grooves 14' and 16', as well
known in the art.
25 Both the screw bit receiving shafts 14 and 16 are
provided with frictional engagement means in the form of
shoulder flanges 21 and 22 for frictional retention in
locating slots 21' and 22' provided in the outermost
sections of the shaft receiving cylinders 23 and 24 secured
3o in the front handle section 12 and rear handle section 13,
respectively.
As shown in Figure 1, a plurality of flexible
projecting fingers 30 extend from a rear circumferential
body portion 31 of the front handle section 12 and
3s clampingly fractionally engage with clamping teeth
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projections 32 formed in the rear handle section 13, as will
be described later.
With specific reference to Figures 3 and 4 it can
be seen that when the screwdriver handle sections 12 and 13
s are disconnected from one another it exposes a bit storage
magazine which is comprised of a plurality of cylindrical
cavities 25 which are formed in the end walls 17 and 27 of
both the rear handle section 13 and the front handle section
12. The cavities in the front handle section have a cross-
~o section adapted to fractionally retain the bits 18 therein.
Figure 5 illustrates that more of these storage
cavities 25 can be formed in the end walls of these handle
sections wherein to provide multi-bit storage. For example,
if eight of these cavities were provided in the end wall and
15 two bits 19 mounted in the chucks 19 and 19' of the bit
receiving shaft 14 and with the bits 18 having opposed screw
heads, then this would provide eighteen options of screw
heads that can be engaged with each of the chuck cavities of
both the stub screwdriver formed by the rear handle section
zo 13 and the chuck cavity of the shaft attached to the front
handle section 12 thereby giving the screwdriver the
possibility of 36 different bit combinations with the use of
both screwdrivers formed with the handle sections.
Referring now to Figures 5 to 8 there will
zs described the construction of the front handle section 12
and its friction clamping fingers. These fingers 31 are
recessed from the outer periphery of the front handle
section and are provided with a transverse indent 33 at a
base thereof above the rear wall 31. The fingers are
30 located intermediate the cylindrical cavities 25 which form
the bit storage magazine. As hereinshown, the cylindrical
cavities 25 are of hexagonal cross-section and define six
wall sections, one of which is constituted by a pliable
thermoplastic elastomer 34 which is injection molded to the
3s rigid plastic body portion 35 of the handle, as shown in
Figure 8. The pliable thermoplastic elastomer 34
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constitutes an outermost one of the six elongated walls 36
of the cavities 25 and also forms an outer handle section 37
which provides improved frictional retention by the hand of
a user person to assist and improve torquing the torque
s transmitting shaft 14 which projects from the front end 15
of the front handle section 12. The thermoplastic
elastomeric wall section 34 is also formed with a projection
34', see Figure 6, to provide improved frictional retention
of a screwdriver bit disposed in the cylindrical cavity 25.
~o As shown in Figure 3, these bits project sufficiently from
the end wall 27 of the front handle section for finer
engagement.
Referring now to Figures 9 to 11, there is shown
the construction of the rear handle section 13. As
15 hereinshown it is also provided with pliable thermoplastic
elastomeric sections 40 disposed between a plurality of
flexible clamping teeth projections 32 spaced apart about
the periphery of the rear handle section and dimensioned for
flexible clamping engagement with the fingers 31 projecting
2o from the front handle portion 12. When the handle portions
are mated together, the elastomeric sections 40 and 37 are
in alignment with one another, and as previously described,
this enhances gripping and the application of torque to the
screwdriver, combined as shown in Figure 3 or to the stub
zs screwdriver.
As shown in Figure 10, the stub screwdriver is
also provided with cavities 25' dimensioned and aligned with
the cavities 25 provided in the front handle section 12.
These cavities merely receive the opposed screw head of the
3o bits stored within the cavities 25 and do not provide
frictional engagement thereof. Accordingly, the elastomeric
sections 40 are not provided with projections 34' as is the
case with the elastomeric portions 34 in the front handle
section.
35 In the particular embodiment as shown in Figures 5
to 11, which is the preferred embodiment, there are six of
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the cylindrical cavities 25 and dimensioned to receive
screwdriver bits 18 having opposed screw engaging heads.
The elongated torque transmitting shaft 14, as shown in
Figure 3, is provided with chuck cavities 19 and 19' at
s opposed ends thereof and also dimensioned to receive
screwdriver bits having opposed screw engaging heads.
Accordingly, the screwdriver results in a dual multi-bit
screwdriver having a capacity of storing eight screwdriver
bits having opposed screw engaging heads to adapt to sixteen
~o different types of screw heads with each the elongated
screwdriver combined or the stub screwdriver.
It is within the ambit of the present invention to
cover any obvious modifications of the preferred embodiment
described herein, provided such modifications fall within
15 the scope of the appended claims.
