U.S. patent number 3,675,516 [Application Number 04/742,987] was granted by the patent office on 1972-07-11 for wrench splines, spline drives and similar couplers.
This patent grant is currently assigned to Snap-On Tools Corporation. Invention is credited to Raymond G. Knudsen, Gene E. Olson, James W. Price.
United States Patent |
3,675,516 |
Knudsen , et al. |
July 11, 1972 |
WRENCH SPLINES, SPLINE DRIVES AND SIMILAR COUPLERS
Abstract
The invention involves multisided and specially shaped jaws or
splines in wrench sockets or other rotary drivers or couplers
configurated around an internal periphery to present uniformly
spaced flat driving sides, jaws, or flanks for flat
surface-to-surface engagement to impart torque turning loads to
complemental flat multifaced externally polygonal fastener faces or
driven coupler elements rather than to the corners thereof, and to
accommodate hexagon, double hexagon, triple square, and
complementally fluted or fluted or multi-splined nuts and the like.
The internal and radially extending peripheral splines are
configurated to present specially angulated engaging jaw sides or
flanks with intervening and alternately spaced complemental grooves
for flat surface engagement with the sides of either hexagon,
double hexagon, triple square, or complementally splined nuts or
the like without any corner engagement therewith.
Inventors: |
Knudsen; Raymond G. (Kenosha,
WI), Price; James W. (Kenosha, WI), Olson; Gene E.
(Kenosha, WI) |
Assignee: |
Snap-On Tools Corporation
(Kenosha, WI)
|
Family
ID: |
24987060 |
Appl.
No.: |
04/742,987 |
Filed: |
April 10, 1968 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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321955 |
Nov 6, 1963 |
3273430 |
|
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589153 |
Sep 14, 1966 |
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580496 |
Sep 19, 1966 |
3495485 |
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Current U.S.
Class: |
81/124.6;
81/176.15 |
Current CPC
Class: |
B25B
13/065 (20130101) |
Current International
Class: |
B25B
13/06 (20060101); B25B 13/00 (20060101); B25b
013/06 () |
Field of
Search: |
;81/53,181,90,121,119
;85/9,45 |
References Cited
[Referenced By]
U.S. Patent Documents
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3273430 |
September 1966 |
Knudson et al. |
3354757 |
November 1967 |
Grimm et al. |
3495485 |
February 1970 |
Knudsen et al. |
|
Foreign Patent Documents
Primary Examiner: Mehr; Milton S.
Parent Case Text
This invention is a continuation-in-part of our copending
applications Ser. No. 321,955 filed Nov. 6, 1963 (U.S. Pat. No.
3,273,430) and Ser. No. 589,153 filed Sept. 14, 1966, now
abandoned, and a continuation of our application Ser. No. 580,496
filed Sept. 19, 1966 now U.S. Pat. No. 3,495,485.
Claims
We claim:
1. A wrench or the like for fluted and standard nut fasteners or
the like having a peripherally closed socket defined by a plurality
of equidistantly spaced peripherally and radially disposed
di-hedral end jaws presenting angularly related straight flat side
jaw surfaces of substantially a range between 140.degree. and
150.degree. therebetween, said side flat jaw surfaces extending
substantially for the depth of engagement for flat
surface-to-surface contact with complementally fitting peripherally
disposed straight flat-sided geometric fasteners or the like for
aligned registry therebetween in longitudinal axial alignment with
said socket, and oppositely disposed flutes with flat side surfaces
defined by said flat side jaw surfaces extending radially to
project oppositely to said first named straight surfaces and
alternately therebetween in integral continuity therewith for
defining a continuous geometric fastener engaging member to impart
turning moments to fasteners in registry therewith, said oppositely
disposed flutes having a depth sufficiently greater than the most
outward corners of said geometric fasteners to avoid contact
therewith and eliminate fastener corner engagement in imparting the
turning load thereto.
2. A wrench structure or the like for fluted and standard nut
fasteners defined in claim 1 wherein the angularly related straight
flat side jaw surfaces tend to converge inwardly toward the axis of
the wrench socket to present outward angles of substantially
144.degree. and the flutes extend outwardly to accommodate the
fastener corners so that their open troughs face the same axis and
their closed ends are substantially concentric therewith to define
a peripherally closed socket for substantially the depth of
standard fasteners for effective registry with complementally
fitting fasteners.
3. A wrench or the like for fluted and standard nut fasteners
defined in claim 1 wherein the angularly related straight surfaces
define pointed corners that extend inward with outward nut flank
engaging surfaces of substantially 144.degree. extending from said
corners, said flank engaging surfaces having angularly disposed
extensions defining outward angles of substantially 45.degree. to
constitute the flat sides of alternately disposed flutes opening
inwardly to face the socket axis for registry with plural shapes of
geometric fasteners to impart a flat surface-to-surface torque load
for nut turning without any possible corner engagement
therewith.
4. A wrench for fluted and standard nut fasteners defined in claim
3 wherein the flutes are sufficiently deep relative to the plural
geometric fasteners to provide clearance with the nut fastener
corners and fluted complementally fitting fasteners.
5. A wrench or the like for fluted and standard nut fasteners
defined in claim 1 wherein the jaws are sharp cornered and the
flutes are substantially flat bottomed for alternate uniform
positioning around the interior periphery of said socket, said
flutes having angularly related oppositely symmetrical flat sides
extending radially toward the socket axis from their substantially
flat bottoms to define peripherally spaced fluted openings for the
reception of the fastener corners and complementally fluted
fasteners.
6. A wrench or the like for fluted and standard nut fasteners
defined in claim 5 wherein the flute sides are differently angled
relative to the jaw engaging sides, and said flute sides constitute
extensions thereof to define splines around the periphery of the
socket to provide flat surface-to-surface engagement in nut turning
plural complementally fitting fastener shapes.
7. A wrench socket or the like for fluted and standard nut
fasteners defined in claim 6 wherein the flutes and splines
constitute the solid configuration of the wrench socket for the
reception of nut corners and their sides, respectively, to provide
flat surface-to-surface flank nut surface engagement with the
corners thereof unengaged by said flutes.
8. A wrench or the like for fluted and standard nut fasteners
defined in claim 1 wherein said contiguous oppositely disposed
pairs of straight jaw surfaces have an outside angle of
substantially 216.degree. relative to each other.
9. A wrench or the like for fluted, splined, and standard nut
fasteners defined in claim 8 wherein said angularly related and
oppositely disposed pairs of straight jaw surfaces present sharp
corners and these are interrupted by circumferentially interposed
concavities to accommodate the corners of the geometric fasteners,
and the bisectors of said corners and concavities are on 15.degree.
radii of the wrench socket axis.
10. A wrench or the like for fluted, splined, and standard nut
fasteners defined in claim 9 wherein said oppositely disposed pairs
of straight jaw surfaces inwardly intersect and said
circumferentially spaced concavities extend outwardly to open
toward the socket axis to provide limited rotary play and
sufficient freedom of registry between the fasteners and the wrench
for improved nut or other fastener turning.
Description
This invention relates to wrench socket drives and more
particularly to improvements in a multisplined socket arrangement
which will accommodate geometric fasteners that are multisided
splines and multiples of hexagons such as but not limited to six,
12 and the like sides. The latter may consist of a double hexagon
or a triple square nut fasteners as well as standard single hexagon
nut fasteners or complementally spline-shaped external nut
configurations which appear to be the most commonly used shape
types.
It contemplates more especially a wrench socket or sockets which
are broached or otherwise shaped to provide a series of
circumferentially spaced and longitudinally extending splines that
are spaced by complementary longitudinal grooves of improved shape
and cross-section extending inwardly from the contiguous splines
which are also of improved shape and cross-section. The concept of
providing driving splines of such number and shape for longitudinal
or axial displacement in relation to hexagon, double-hexagon or
triple-square nut fasteners and to transmit turning or torsional
turning engagement thereto for rotary displacement of the fasteners
as a multisided flank drive therefor, involves splined engagement
with the fastener sides without impact with and free of all contact
of their multisided corners to prevent mutilation thereof.
This is accomplished without any appreciable relative movement in a
rotary direction which is limited to bare minimum and tolerable
play which is necessary and yet understandably small to insure free
registrable positioning between the wrench sockets and the nut
fasteners preparatory to turning for the tightening or loosening
application thereof relative to a threaded counterpart on a machine
or other assembled device. With the teachings of the present
invention, the wrench socket is splined to provide, in this
instance, twelve inwardly projecting splines with each presenting
angularly related and inwardly inclined sides from 45.degree. more
or less and presenting substantially V-shaped roots or spline tips
of between 140.degree. and 150.degree. more or less. The driven
complementary grooves alternate between the splines, and
accommodate the corners of the nut fasteners so that the mutilation
thereof in the region of the corners where fasteners are most
vulnerable, will be completely eliminated.
It is worthy of note that this type of wrench socket configuration
will accommodate also splined nut fasteners that are complements
thereof, but the primary objective is to transmit torsional or
rotary displacement to hexagon, double hexagon and 12-sided square
nut fasteners which are in common use and to provide a flank drive
therefor to more effectively sustain nut turning loads. This
insures surface-to-surface flat engaging contact between the
splines or radial jaws and the flanks of the nut fasteners
irrespective of whether or not the spline-shaped complemental
fasteners, the single hexagon fasteners, the double hexagon
fasteners or the triple square-shaped fasteners or their
counterparts in the form of coupler elements or shafts employed for
any specific purpose requiring torque or turning loads. With this
arrangement, the multisided driven elements are engaged away rather
than at their corners where such are prone to multilation. Straight
surface-to-surface contact and turning engagement for the flank
surface load transmitting contact is assured, and greater torque
loads can be transmitted with the spline or multijaw wrench
embodying the teachings of the present invention.
One object of the present invention is to provide an improved
multi-sided drive for a variety of different fasteners such as
spline nuts, hexagon nuts, double hexagon nuts and triple square
nuts or fluted coupler parts complementally fitted for flank
surface engagement therebetween.
Another object is to provide an improved and more versatile wrench
socket of the fluted type to insure surface-to-surface flank
engagement between its splines and the flanks of a variety of
multisided fasteners or coupler parts.
Still another object is to provide an improved multisplined wrench
socket or coupler element which is shaped to accommodate spline,
single hexagon, double hexagon and triple square shaped standard
nut fasteners for flank engagement with the multisides thereof and
without any possible mutilation of the fastener corners so that
torque turning capacities are increased without any change in the
design or wall thicknesses of the drivers.
A further object is to provide an improved spline driver or wrench
socket which is confined to flank engagement with multisided or
cornered driven members of different shapes to insure maximum
turning loads over an extended period of time without mutilation
thereto.
A still further object is to provide a spline socket or fluted
driver coupler element which has improved turning characteristics
for maximum load capacities and minimum mutilation of both the
driver and driven members.
Other objects and advantages will appear from the following
description of an illustrated embodiment of the present
invention.
In the drawings:
FIG. 1 is a perspective view of a driver element or wrench socket
embodying features of the present invention.
FIG. 2 is an end enlarged view of the socket illustrated in FIG. 1
in registry with either a single hexagon or double hexagon driven
element such as fastener nuts, each being superimposed over the
other to illustrate the possible different fasteners adapted
thereto.
FIG. 3 is an enlarged fragmentary sectional view taken through a
spline or protuberance comprising a preferred shape of one of a
plurality of circumferentially spaced teeth inside the socket.
FIG. 4 is an enlarged end view of the socket which is also adapted
to register with a splined complemental fastener nut or coupler
part to illustrate the fastener variations possible therewith.
FIG. 5 is an enlarged end view of the broached end of a socket like
that shown in FIG. 1, but adapted to register with a triple square
nut fastener or coupler driven member to illustrate yet another
type of driven fastener formation usable therewith.
The structure selected for illustration is not intended to serve as
a limitation upon the scope or teachings of the invention, but is
merely illustrative thereof. There may be considerable variations
and adaptations of all or part of the teachings depending upon the
dictates of commercial practice. The present invention is
exemplified, in this instance, by a cylindrical wrench socket 10
preferably though not essentially provided with a reduced
cylindrical base 11 having a polygonal axially positioned bore
therethrough, in this instance a square-shaped bore 12 for
receiving a correspondingly shaped but slightly smaller drive shaft
in registry therewith for detachable association in the customary
manner for imparting rotation or turning movement in tightening
fasteners registered or telescoped therein as will appear more
fully hereinafter.
The base 11 of the socket 10, merges in a somewhat enlarged
cylindrical body 13 that is interiorly broached or otherwise
polygonally shaped from the opposite end 14 thereof to present a
definite and precise polygonal socket 15 which shall be presently
described. The socket 15 usually communicates with the drive bore
12 so that the chips resulting from the broaching of the socket 15
will find their way through the bore 12. In the present embodiment,
a socket 15 is provided for a hexagon nut (FIG. 2), a double
hexagon nut superimposed on the single hexagon nut in FIG. 2, a
splined complemental nut (FIG. 4), and a triple square nut (FIG.
5). The driver or socket 15 has its larger end specially
configurated internally to provide a side drive or flank
surface-to-surface engagement relative to a complemental fastener
nut used in engines and other devices held assembled therewith.
The standard hexagon or double hexagon socket usually comprises a
series of equidistantly and alternately disposed relatively inward
and outward corners to correspond with and afford substantially
exact registry over the nut fastener sized therefor, and in the
case of a twelve splined or double hexagon socket 15, the nut can
be fitted therein every 30.degree. turn rather than 60.degree. and
for a triple square-nut every 30.degree. as well as with a
12-splined complemental nut to afford a double or triple bite
thereon in one-half or one-third of the usual arc of rotation for
greater accessibility in restricted spaces or locations. These
advantages are somewhat offset by the reduction in wall thickness
due to double or triple broachings with twice the outer corners
that reduce wall body thicknesses in the region thereof. It is
these corners in standard sockets that, for the most part, carry
the turning or torque load imparted to the fastener nut of four or
six or more corners and, therefore, the stress is the greatest in
the weakest regions around the periphery of the wrench socket 10,
although the same problems pertain to similarly shaped driven
members or couplers with their counterpart drivers.
To overcome this decided disadvantage and weakness, the wrench
socket 15 and for that matter its counterpart in a male drive
should such be desired for recessed heads of screw fasteners and
the like, is provided with a series of equidistantly spaced and
circumferentially disposed side engaging lands or jaws better
termed splines 16 of improved design, in this instance 12 in
number. The special shaped splines 16 extend inwardly toward the
axis of the socket 10, which alternate with equidistantly and
circumferentially spaced slots or flutes 17 preferably of special
shape and cross-section to provide flank surface-to-surface
engagement with fastener sides and allow the corners thereof to be
freely received within the flutes 17 as will be better understood
from the following description. The angular surfaces 18-19 of the
splines 16, intersect and converge to form inner spline corners 20
that align with radii, in this instance 30.degree. apart. These
splines 16 have their angularly converging surfaces 18-19 terminate
in spline root sides 21-22 which are relatively angled at
45.degree. to also constitute the sides of the flutes 17 contiguous
therewith.
The flute sides 21-22 terminate in a circumferential slightly
arcuate bottom 17 that is relatively flat and extend outwardly
while the opposite open portions thereof extend inwardly to receive
the spline ends 16' (FIG. 4) or sharp corners 23 of the single
hexagon nuts (FIG. 2) and the corresponding sharp corners 23-24 of
the double hexagon nuts shown superimposed on the single hexagon
fastener in the illustration (FIG. 2). These spline sides 21-22
define the angular sides of the flutes 17 which afford complete
clearance for the nut corners 23-24 to avoid any turning load
thereon and preclude mutilation thereof in that the turning impact
and load is concentrated away from the fastener corners 23-24 where
there is sufficient surface body to more effectively sustain the
torque turning load without any defacement, and there is
surface-to-surface engagement between the spline sides 18-19 and
the nut sides away from the outer corners 23-24.
While the hexagon and double hexagon fastener nuts are in registry
with the splined socket 15, only straight and extensive side nut
surfaces are under torque load and consequent stress and this takes
place in the thickest region of the socket wall 13 where it is the
strongest so that increased capacity is attained without varying
the thickness of the socket wall which are usually as thin as
possible for greater accessibility in tight or restricted places.
In either clockwise or counterclockwise turning rotation, this
surface-to-surface contact and load bearing engagement is
accomplished. In either event, the fastener nut corners 23-24 are
stressed or load bearing, and correspondingly the alternate troughs
or flutes 17 which are in the thinnest regions of the wrench socket
wall 13, are never under direct stress so that torque transmission
for tightening or loosening the fastener nuts are transmitted by
the strongest portions of the wrench sockets 10.
This is the converse of loading stress in the conventional wrench
sockets of both the single hexagon and double hexagon standard
design. In the latter especially, there is the greatest load in the
corners where the wall thickness is minimum and comparatively thin
owing to the twelve cornered configuration which eliminates
considerable body and, therefore, is substantially weakened and
less able to sustain repeated heavy loads over an extended period
of time. The nut corners are especially vulnerable to mutilation
with the standard hexagon and particularly double hexagon socket in
that the load engagement is at the corners which region are
susceptible to the greatest mutilation by reason of the limited
body engagement at these points. With the teachings of the present
invention and design, the greatest torque sustaining load is borne
by the comparatively large side surface engagement of both the
wrench socket 15 and the nut sides at points removed or away from
the corners of the nuts so that the nut turning loads are borne in
the strongest regions of both.
Thus the alternately spaced flutes 17 accommodate the nut corners
to eliminate any possible stress thereon and consequent mutilation
through the provision of side surface driving splines 16 which are
supported and reinforced by the thickest regions comprising the
inside socket corners which are the spline roots. The fastener nut
corners 23-24 are not, therefore, the engaging abutments for the
socket splines 16 so that the torque transmitting characteristics
of the wrench socket 10 are substantially increased without
increasing the thickness of the socket wall 13 which should be as
thin as possible for utmost accessibility in tight places, this
being in accordance with the dictates of commercial practice which
tends to thinner and thinner socket designs. This renders the
sockets more accessible in restricted nut locations on modern
engines and other equipment.
It is worthy of note that the angularity of the flute sides 21-22
is not critical so long as the torque transmitting engagement with
the fastener sides are substantially tangential in the region of
contact and the depth of the flutes 17 is sufficient to provide
minimum clearance for the nut corners 23-24 to insure that there is
no load thereon during nut turning, and that the turning load is in
the region of maximum socket wall thickness as explained supra,
rather than in the critical regions which are the outer recess
corners in standard socket constructions. Further, to provide for
direct tangential flank engagement with the use of spline-shaped
fasteners 25 (FIG. 4) as well as with other types of nuts described
above, flute sides 26-27 are provided to constitute relatively
angular extensions of the spline sides 18-19, and to attain the
most direct tangential side engagement in transmitting the torque
load their angle relative to each other is preferably though not
critically essential substantially 45.degree. (see FIGS. 2 and 3)
for substantially normal engagement with complemental splines 17'
comprising the periphery of a total spline fastener 25 (FIG. 4)
which also could be a shaft or other coupler element. This flute
angularity is also preferable for procuring substantially the same
directional surface-to-surface engagement with a single and double
hexagon (FIGS. 2) and a triple square fastener (FIG. 5) comprising
a standard nut 28 which are in use but not nearly as frequently as
the single and double hexagon fasteners. The corners 29 of the
triple square fastener 28 approach the outside ends 30 of the
flutes 17 more closely as illustrated, but in practice this limited
clearance is sufficient to avoid corner engagement with possible
eventual mutilation, and thus the same advantages accrue
therewith.
The greatest advantage not only is improved transmitting
characteristics and torque load capacities, but also the transfer
of the turning moment and its resultant stresses to the inside
spline socket surfaces 18-19 and the interior corners 20 thereof
where the wall thicknesses are the greatest rather than the least
as in standard socket formations, and the torque load is applied
for the most part to the side surfaces 18-19 of considerable
expanse compared to the restricted corners as previously occurred
so that the unit area load is minimum and both the socket 10 and
fastener nuts of the different types illustrated sustain the loads
in the regions of greatest strength. In the region of minimum
strength and thickness which in standard wrench sockets and
fasteners are at their outside corners, the improved construction
is relieved of all corner contact stress and strain by providing
the specially designed and contoured flutes 17-30 that are non-load
bearing at all times.
While the outside angularity (relative to the socket axis) between
the oppositely inclined fastener flank engaging surfaces 18-19 need
not be precisely limited within a matter of several degrees (more
or less), it has been found that with a specific angle of
substantially 144.degree. therebetween a very effective ratio
exists between required looseness for fastener registry with its
socket 15 and the desired region of engagement away from the
fastener corners, although the range between 140.degree. to
150.degree. for said outside angle or angles is deemed tolerable
and within the dictates of commercial as well as practical
considerations. Important too is the fact that these advantages can
be acquired without changing the shape, sizes, design or
specifications of the geometric fasteners which have, for the most
part, been standard for such long periods that it would be scarcely
possible to expect changes therein without extended resistance. For
these reasons, it is imperative or at least most desirable to
improve the design and structure of the sockets or turning drivers
utilized for nut turning and as couplers in other situations.
While we have illustrated and described a preferred embodiment of
the invention, it must be understood that our invention is capable
of considerable variation and modification without departing from
the spirit of the invention. We, therefore, do not wish to be
limited to the precise details of construction set forth, but
desire to avail ourselves of such variations and modifications as
come within the scope of the appended claims.
* * * * *