Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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1 rrhis application is a divisional of Applica-tion Serial
Num~er 319,891 filed January 18, 1979~
The present invention provides an economical apparatus
for splitting logs that is particularly suitable for home use.
Mechanical log splitters have ~een in use for commercial
applications, but no completely satisfactory device has been
available for the individual who desires to split logs for his
own use. The available commercial devices are both expensive
and hazardous to use making them unacceptable for home use.
Such splitters as have been made available at a price to qualiy
them for home use have either been ineffeckive, awkward to use
or excessively hazardous to operate.
It is an object of this inven-tion to provide a log
splitter that is easily operated, either manually or power-driven,
and which creates minimum hazard in its use.
It is another object to provide such a log splitter
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having a wedge with a single point that engages the end of the
log to be split.
It is still another object to provide such a device
which supports the log only in the central area of the bottom
surface.
Another object is to provide a log splitter having a
pointed splitting wedge having converging edges forming a point
and converging surfaces terminating at the same point.
Another object is to pro~ide a vertical log splitter
having a movable lower support for receiving the bottom end of
a log to be split and an upper splitting wedge secured to a
vertical frame by a quick-release hand-operated lock.
Still another object is to provide a log splitter in
which vertical forces are applied to split the log without the
generation of substantial lateral forces.
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1 To this end, in one o it~ ~spec-ts~ this inven-tion
provides in an apparatus for splitting a log, a combinatlon
comprising,
a frame,
a carriage mounted on said frame,
a wedge secured to said carriage and having a terminus
adapted to engage one end of a log to be split,
support rneans for the opposite end of said log, and
drive means ar;ranged to produce relative closing move-
ment between said support means and said carriage,
said support means having a ~irst surface generally
facing said wedge, a projection extending from said first sur~ace
in alignment ~ith said terminus in the direction of the path of
said closing move~ent, said projection having a second su~face
of at least one square inch generally ~acing said wedge and being
spaced from said first surface and adapted to engage said oppo-
site end o~ said log and prevent cont~ct between said log and
said first surface adjacent said pro~ection thereby to minimize
the generation of twisting moments
These and other objects will he ln p~rt pointed out
in and in part apparent from the follow~ng description of a pre-
ferred embodiment of the in~ention considered in conjunction with
the accompanying drawings, in which:
- Figure 1 is an elevational view o~ a log splitter
embodying the invention;
Figure 2 is a sectional view taken along line 2-2 of
Figure l;
Figure 3 is a plan view of a locking member used in
the log splitter;
Figure 4 is an elevational view of a power drive
attached -to the log splitter jack;
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1 ~igu.re 5 is a plan view of the drive o~ Figure a;
E`igure 6 is a partial sectional view of the drive taken
along line 6-6 of Figure 7; and
Figure 7 i.s a partial sectional view taken along line
7-7 of Figure 6.
The log to be split is supported in a vertical position
by an I-beam 2 having an upper projection 4 that engages the
central area of the bottom of the log. The log is split by a
wedge, generally ind.icated at 6 in Figures 1 and 2, having a
point 8 that makes initial contact with the upper end o~ the log,
The vertical design of the log splltter is advantageous in that
it permits logs of di~erent diameters to be centered readily on
the projection g and the wedge point 8. Such centering is dif~
ficult or imposs.ible with splitters in which the log is mounted
in a horizontal position. ~.
In order to split the log with minimum force and mini-
mum stroke, the wedge 6 is tapered in two directions. From a
front view as shown in Figure l, the point is formed by two
linear tapered edges lO and 12. The wedge 6 is also tapered in
the plane at 90 degrees from the front view of Figure 1 as shown
in Figure 2. The wedge 6 is formed of two steel plates 14 and
l~ which are curved on a radius as indicated at 18, positioned
to form an acute angle, and welded together near the bottom edge
to form a solid blade portion 20 that has a short linear taper ~:
that terminates in an edge along the bottom of the wedge and
30ins the radii 18 along its top. This double-tapered wedge
construction requires less force to cause initial penetration
than woul~ a conventional wedge that makes a line contact with
the end of the log and it also causes the log to split with less :~
penetration than would be required by a conventional single-taper ~ :
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1 wedge. As used herein, the term double-tapered wedge means a
wedge having two side surfaces that form an acute angle and which
meet along two edges that~ in another plane, form an acute anyle
with an apex at an e~tre~ne point of the wedge~ The wedge may be
formed in any deslred manner, as by two separate parts welded
together, or it may be cast as a single piece and machined to the
desired dimensions.
As shown at 24, khe plates 14 and 16 are welded along
their upper edges to a carriage 22 which is slidably posltioned
on two vertical standards, formed of steel pipe, by means of two
cylindrical guides 30 and 32, of square cross section~ arranged
to slide vertically on the standards 26 and 28~ The wedge is
manually adjusted yertically by means of a handle 34 secured to
the carriage 22 and locked in position b~ two qu~ck-release
clamps, generally indicated at 36 and 38~ These clamps axe nor-
mally maintained in locked position by two generally U-shaped
leaf springs 40 and 42 which are secured at one end area to t~e
carriage 22 with the free upper end of each spring exertin~ an
upward force on a stack of five locking members 44. Each of the
locking members is a flat steel plate having an enlarged rectan--
gular end portion 46 (Figure 3) with a central hole having a
diameter slightly greater than the outside diameter of the ~;~
standards 26 and 2~ so that when the locking member is canted
with respect to the standard, it binds against the standard and
is locked in position. Each of the locking members passes
through a rectangular opening 45 in a fulcrum member 47 and
pivots about the upper surface of the open~ng 45~ To prevent the
scoring of the standards 26 and 28 by the cla~ping action from
interfering with the free sliding movement of the guides 30 and :.
32, each of the openings in the locklng members is relie~ed~ in
,
1 the area adjacent the outer surace of the standard which passesthrough it, by a notch 50. The clamping force is thereEore
applied to areas indicated at 52 in Figure 3~ If this clamping
action scores the standards 26 and 23, it is of little conse-
quence because the score marks will occur in poxtions of the
standards passing through the corner sections of the rectangular
guides that do not engage the surfaces of the round standards.
When the handle 34 is grasped, the end portions of the
locking members 44 are enclosed in the grasp and moved against
the force of the leaf springs 40 and 42 into a generally horizon-
tal position releasing the lock on the standards and permitting
the entire carriage and wedge assembly to be moved vertically.
Upon release of the handle 34, the locks 36 and 38 re-en~age the
standards and secure the wedge assembly in position, locking
it securely against any upward force
In use the wedge assembly is lifted to its highest
position, the movement being limited by two top caps 53 threaded
onto the standards 26 and 28, and the log is placed verticall~
on the projection 4 and held in that position while the carriage
~0 and wedge assembly is lowered so that the wedge point 8 engages
the upper sur~ace of the log and holds it in position~ The
projection, 4 making essentially point contact with the log~
prevents the application of a transverse force to logs having an
angular lower end surface when the splitting force is applied,
~he projection 4, which may be of any cross-sectional shape, has
a surface area small in comparison with the end area of the
smallest log to be split and may, typically, have between one
and eight square inches, but must of course be functionally large
enough to maintain essentially point contact no matter what type
of wood is being split. The point contact of the wedge on the
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1 upper end also serves a similar func-tion and prevents the deve-
lopment o~ lateral forces on logs having an angular end surface.
This alignment o~ forces allows applica-tion of large splitting
forces wi-thout generating bending moments, permitting the use of
a lighter and simpler frame than would otherwise be required,
The design of the log splitter makes it possible to
split logs with a diameter larger than the distance between the
two standards 26 and 28, by placing the log off-center between
the projection 4 and the wedge point 8 and reducing the diameter
of the log by multiple splits.
The I-beam 2 is slidably supported on the standards 26
and 28 by two cylindrical guides 54 and 56, also of rectangular
cross section, which fit around the standards, The guides 54 ;~
and 56 are long enough to permit relatively free movement on the
standards in spite of any expected twisting or off-center forces
on the I-beam 2.
~ ith the log positioned between the I-beam 2 and the
edge 6, the splitting action is produced by forcing the beam
upwardly and driving the log into the wedge 6. The necessar~
~O force is conveniently produced by a hydraulic jack, generally
indicated at 60, which may be an ordinary automobile jack of the
kind intended to be operated by foot action~ ~.
The hydraulic jack 60 rests on a supporting I-beam 62
which in turn is supported by two parallel steel channels 64
that serve as a stable base ~or the splitting unit. The moy~ble
ra~ 66 of the jack 60 abuts the underside of the ~-beam 62 ~nd
advantageously may be positioned in a recess so the ram ~ill not
accidentally be dislodged during use,
The jack 60 has a handle 68 that is intended Eor ver-
tical reciprocal movement by foot action. When the handle is
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t forced down, the conventional cam mechan:Lsm opera-tes the jack in
the usual manner, the handle then being returned, by a spring 70,
to its upw~rd position upon release o~ the downward ~orce.
.~ovement of the handle forces the I-beam upwardly to produce the
compressive force between the log and the wedye 6.
When the log has been split, the hydraulic pressure in
the jack 60 is released by a foot-operated lever 72 and the
I-beam 2 is returned to its lowermo~;t position by two tension
springs 74 and 76 extending between the two beams 2 and 62.
For reasons o~ economy and to minimize the overall
hei~ht Oe the structure~ the jack 60 has a relatively short stroke,
for example, about six inches, which is sufficient with the wedge
structure already described to split most logs~ ~lowever, if a
longer stroke is needed to complete the splitting action, the
jack 60 is allowed to return to its retracted position, by opera-
tion of the lever 72, while the clamps 36 and 38 are held in
release position. The entire log-holding assembly is then moved
downwardly so that the full stroke of the jack 60 is again avail-
able to drive the wedge 6 farther into the log~ The log splltting
apparatus described is particularly sa~e to operate because of
the slow movement of the parts and the absence of lateral forces7
In order that the log splitter ma~ be easily moved from
one location to another, a pair of wheels 75 are attached near
the ends of the base channels 64, By tilt~ng the entire splitter
so that it is balanced on the wheels 75, lt can be moved readily
in the manner o~ a conventional hand truck~
The required manual labour is reduced and the speed of
the splitting operation is increased by the use of a power drive~
The electric drive system sho~n in Figures 4-7 is particularly
well adapted for this purpose. It is attached to the jack 60
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1 with a minimum of modifications so t~at it is poss:ible to add the
electr;c drive to the same jack that is used Eor manual operation.
A universal electric mo-tor 77 is coupled to a speed-
reducing transmis~ion, generall~ indicated a-t 7~, which may be
of any desired type, such as the one described in my U.S. Patent
3,574,489. The motor and speed reducing transmission are mounted
on the jack 60 by a pin 79 extending between the mounting brac-
kets 80 and 82 and through a mounting collar 84 on the housing
of the motor and speed reducing unit~ The pin 79 is used as a
pivotal mounting for the jack handle 68 in the manually-operated
embodiment. The housing îs also secured to the jack by an arm
86 extending between the housing of the speed reducer and a
collar ~8 around the body of the jack~
To produce the n~cessary reciprocating motion~ the
driven sha~t 90 ~rom the speed reducer 78 is secured to a drive
disk 92 mounted eccentrically on the shaft 90 and which ls
surrounded by a sliding collar assembly 94. This collar assembly ::
includes a pair of spaced arms 96 connected by a cross pin 98
which is maintained in abutment with the end of the jack piston
100 by a U-shaped clip 102, Rotation of the shaft 90 produces
a reciproca-ting motion of the piston 100 and causes the ram 66
of the jack to move upwardly. The pressure release of the jack
is controlled in the same manner as with the manually-operated
unit.
The electric drive unit is mounted directly on the
jack 60 and may be removed as an integral part with the jack
from the remainder of the log splitter assembly. Thus, the -~
electrically driven jack may be used for a wide variety of appli-
cations where economy is important and it is desired to $ake
advantage of the :Low cost of commercial hydraulic jacks~ It is
t.~
1 to be no-ted that ~he motor drive unit can be used to convert any
standard commercial hand-oper~ted hydraulic pump o~ sel~-contained
lifting jack in~o a power-operated unit at a fraction of the
cost of conventional systems. ~Jo modification of the pump is
required and there are no hoses or separate valving systems to
be provided. The drive configuration with its linkage method o~
attachment to the pump is simple, effective, and requires no
precision machining,
From the foregoing description o~ particular embodi-
ments of my invention it will the apparent that my invenkion i5
well adapted to meet the ends and objects herein set ~orth~ to
be economically manuactured, and that it is subject to a wide
variety of modi~ications to best adapt ~t ~oreach lntended
application.
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