Hydraulic wood splitter

A hydraulic wood splitter is disclosed which is configured for highly efficient and convenient wood splitting operation. In order to retain wood being split in proper position on the frame of the splitter, the construction includes a wood-retaining configuration for the wood-abutting splitting rams of the construction. Each ram includes a peripherally extending retaining lip which cooperates with an elongated slot defined by the frame of the splitter for retention of wood in proper position thereon. Additionally, the splitting wedge of the device is provided with a dual-tapered or double-beveled configuration for further facilitating convenient and efficient wood splitting.

TECHNICAL FIELD OF THE INVENTION 
The present invention pertains generally to hydraulically operated wood or 
log splitters attachable to a tractor or the like, and more particularly, 
to an improved hydraulic wood splitter having an improved wood-retaining 
and splitting construction. 
BACKGROUND OF THE INVENTION 
Hydraulically operated wood splitting devices are well-known and therefore 
have been provided in a variety of forms. One particularly efficient, 
highly versatile, and conveniently operated wood splitting device is of 
the self-elevating type such as disclosed in commonly assigned co-pending 
applications Ser. No. 485,964, filed Apr. 18, 1983, and Ser. No. 486,933, 
filed Apr. 20, 1983. These self-elevating wood splitters are desirably 
compact such that they may be used as attachments to tractors or other 
implements having a source of hydraulc power. In addition to being 
compact, these self-elevating wood splitters are capable of generating 
relatively high splitting forces, and therefore can be used efficiently 
for splitting relatively large logs or pieces of wood. Each of these 
self-elevating wood splitters includes a hydraulic actuator comprising a 
cooperating cylinder and ram which in combination generate the high 
splitting force necessary to cut large logs and pieces of wood. 
After initial placement of a log or piece of wood on the frame of a 
splitter, it is desirable that the log or piece of wood be retained on the 
wood supporting frame of the splitter during operation. However, it can be 
inconvenient for the user to manipulate the wood to keep the wood properly 
positioned on the splitter frame, particularly if the end portions of the 
piece of wood are disposed at an angle to the line of splitting force, 
since the forces generated can tend to dislodge or "cock" the wood from 
its desired position. Therefore, it is desirable to have the wood retained 
in proper position on the frame as conveniently and efficiently as 
possible to further facilitate efficient and convenient use of the wood 
splitting machine. 
To this end, the present wood splitter includes a wood-retaining frame 
construction including retaining means that are adapted to initially 
engage the log or wood to provide retention of the log on the wood 
splitter frame immediately upon beginning of the splitting operation. 
Additionally, the present splitter includes a splitting wedge having 
double-beveled or dual-tapered configuration which acts in combination 
with the retaining means of the splitter to further facilitate efficient 
operation. 
SUMMARY OF THE INVENTION 
The wood splitter of the present invention is desirably configured to 
automatically retain logs or other pieces of wood in proper position on 
the wood supporting frame of the splitter during splitting operations, 
even if the pieces of wood have end portions which are not disposed 
perpendicularly to the line of splitting force of the splitter. 
Additionally, the present hydraulic wood splitter includes a splitting 
wedge having a dual-tapered or double-beveled cutting portion to 
facilitate highly efficient cutting action. The inclusion of the 
dual-tapered cutting portion allows the high splitting forces generated by 
the wood splitter's hydraulic actuator to be translated into a high 
initial penetrating force for cutting knots or stringy material, and 
desirably provides the cutting edge with sufficient stiffness to resist 
rippling or any tendency of the cutting edge to follow the wood grain. The 
inwardly disposed portion of the dual-tapered wood cutting portion is 
defined by an included angle which is substantially less than the included 
angle defining the outermost splitting surfaces, thus allowing the 
splitting wedge to pass through wood relatively easily with less required 
splitting force. 
The wood splitter of the present invention is desirably adapted to be 
mounted on a tractor or like implement, and includes an elongated wood 
supporting frame which extends rearwardly of the tractor, and which 
includes a horizontal upper surface. The upper surface of the frame 
preferably defines an elongated slot which acts to maintain wood received 
upon the upper surface of the frame in proper position with respect 
thereto. 
The present splitter further includes splitting wedge means and splitting 
ram means associated with the wood supporting frame. The hydraulic motor, 
preferably comprising a double-acting hydraulic actuator, is mounted on 
the frame, and is operatively connected with one of the splitting ram 
means and splitting wedge means for relatively moving the ram means and 
wedge means toward each other for splitting of wood therebetween. In the 
illustrated embodiment, the splitting wedge means comprises a splitting 
wedge having a pair of oppositely disposed cutting edges, while the ram 
means comprises a pair of rams generally disposed at respective opposite 
ends of the frame for respective coaction with the cutting edges of the 
splitting wedge. It will be recognized, however, that while the present 
wood splitter has been illustrated as a so-called "double-acting" type, a 
wood splitter embodying the principles of the present invention may be 
configured as a "single-acting" type of splitter. 
Significantly, the ram means of the present splitter is configured to coact 
with the elongated slot defined by the splitter's wood supporting frame 
for retaining a piece of wood in proper position on the frame. The ram 
means comprises a generally vertically oriented ram having a ram face 
extending transversely of the wood supporting frame and perpendicular to 
the upper surface of the frame. The ram means further include retaining 
lip means extending about the peripheral portion of and projecting from 
the ram face. The peripherally extending, generally U-shaped configuration 
of the retaining lip means desirably acts to retain a piece of wood on the 
upper surface of the splitter's frame during splitter operation. The 
configuration of the lip means is such that the end portion of a piece of 
wood being split is penetrated by or confined within the peripherally 
extending lip means so that the wood is held in proper position on the 
splitter frame. Thus, efficient and convenient operation of the splitter 
is greatly facilitated. 
To further enhance the efficiency of the present splitter, it preferably 
includes a splitting wedge having a dual-tapered or double-beveled 
configuration. Specifically, the splitting wedge includes a pair of 
oppositely disposed, dual-tapered cutting portions respectively defining a 
pair of oppositely disposed cutting edges. Each dual-tapered portion of 
the splitting wedge defines a first outermost splitting portion having a 
pair of divergent first splitting surfaces, and a second splitting portion 
disposed inwardly of and adjacent to the first splitting portion, and 
having a pair of divergent second splitting surfaces. 
Notably, the first divergent splitting surfaces, which meet to form the 
cutting edge of the wedge, are defined by a first included acute angle 
which is substantially greater than a second included acute angle which 
defines the second splitting surfaces of the second splitting portion. In 
the preferred form, the first included angle is approximately twice the 
second included angle. By this configuration, the sharpness of the cutting 
edge is desirably maintained, and avoids the need for heat-treating of the 
cutting edge which would otherwise make the edge excessively brittle. The 
relatively lesser second included angle allows the splitting wedge to pass 
through wood more easily after initial penetration by the first splitting 
surfaces of the outermost first splitting portion. Again, highly efficient 
wood splitting is facilitated by this unique arrangement. 
Numerous other features and advantages of the present invention will become 
readily apparent from the following detailed description, appended claims, 
and accompanying drawings.

DETAILED DESCRIPTION 
While the present invention is susceptible of embodiment of in various 
forms, there is shown in the drawings and will hereinafter be described a 
presently preferred embodiment with the understanding that the present 
disclosure is to be considered as an exemplification of the invention and 
is not intended to limit the invention to the specific embodiment 
illustrated. 
With reference now to FIG. 1, therein is illustrated a wood splitter 10, 
embodying the principles of the present invention, mounted on the rear of 
a tractor, generally designated T. Wood splitter 10 is illustrated as 
including a self-elevating supporting arrangement generally of the type 
disclosed in co-pending applications Ser. No. 485,964, filed Apr. 19, 
1983, and Ser. No. 486,933, files Apr. 20, 1983. This self-elevating 
mechanism includes a pair of four-bar linkages 12 (one being shown) each 
including a top link 14 and bottom link 16 pivotally connected at 
respective ends thereof to a mounting plate 17 attached to tractor T. The 
opposite respective ends of links 14 and 16 are respectively pivotally 
connected at 18 and 20 to a mounting plate 22. It will be understood that 
in the typical construction, a pair of four-bar linkages 12 are provided 
on respective opposite sides of the splitter 10. 
As further illustrated in FIG. 1, splitter 10 includes a generally 
elongated splitter frame 24 connected to mounting plate 22 having an upper 
horizontal surface which defines an elongated slot 28. Additionally, 
splitter 10 can include a cutting table 26 for added convenience during 
splitting operations. 
The working action of splitter 10 is provided by a double-acting fluid ram 
or hydraulic actuator 30, as shown in phantom line in FIG. 1. Hydraulic 
actuator 30 is of conventional construction, and includes a piston 32 
moveably disposed within a cylinder 34. A hydraulic valve 36 is typically 
provided for operation of actuator 30, with fluid communication of the 
actuator with a suitable source of pressurized hydraulic fluid on tractor 
T being provided via hydraulic lines 38. 
To effect wood splitting, the present splitter includes splitting wedge 
means and splitting ram means, with actuator 30 operatively connected with 
one of the wedge means and ram means. Accordingly, cylinder 34 of actuator 
30 is fixedly connected with splitter frame 24, while piston 32 of the 
actuator 30 is operatively connected with a generally box-shaped beam 40 
at connection 42. Beam 40 is mounted within frame 24 for longitudinal, 
reciprocating movement with respect thereto in response to fluid 
pressurization of actuator 30. 
Splitting wedge 44 is fixedly connected to beam 40, and extends upwardly 
therefrom through elongated slot 28 for reciprocating movement 
logitudinally of splitter 10. Notably, wedge 44 is provided with a 
dual-tapered configuration at each of its oppositely disposed cutting 
portions. This construction is best illustrated in FIG. 4 which shows 
wedge 44 as including a central body portion 46, and a pair of oppositely 
disposed dual-tapered or double-beveled portions 48 respectively defining 
a pair of oppositely disposed knife-like cutting edges 50. 
The configuration of dual-tapered portions 48 has been found to 
particularly enhance the splitting efficiency of splitter 10. Each 
dual-tapered portion 48 includes a first outermost splitting portion 
having a pair of divergent first splitting surfaces 52 which define 
cutting edge 50. Each dual-tapered portion 48 further includes a second 
splitting portion disposed adjacent the first splitting portion including 
a pair of second divergent splitting surfaces 54. As shown in FIG. 4, 
first divergent splitting surfaces 52 are defined by a first included 
acute angle "alpha" which is sustantially greater than a second included 
acute angle "beta" which defines second divergent splitting surfaces 54. 
Significantly, this dual-tapered configuration has been found to provide a 
high initial penetrating splitting force at cutting edge 50 defined by 
splitting surfaces 52, with the more gradual taper of second splitting 
surfaces 54 allowing the wedge 44 to pass through wood more easily with 
less required force. 
In the preferred form, first included angle "alpha" is approximately twice 
the value of second included angle "beta." Angle "alpha" is preferably 
selected in the range of approximately 16 to 24 degrees, with an angle 20 
degrees having proved particularly suitable. Angle "beta" is thus 
preferably provided in the range of about 8 to 12 degrees. As also shown 
in FIG. 4, the length "y" of the first splitting portion including 
surfaces 52 comprises approximately 10 to 20 percent of the total length 
"x" of the dual-tapered portion 48. 
For wood splitting coaction with splitting wedge 48, splitter 10 includes a 
pair of wood-abutting rams 56 disposed at respective opposite ends of 
splitter frame 24. Significantly, each of splitting rams 56 is configured 
to act to retain a piece of wood on the upper surface of frame 24 during 
splitter operation, thus greatly facilitating convenient and efficient use 
of the splitter. 
As best illustrated in FIGS. 2 and 3, each splitting wedge 56 comprises a 
mounting member 58 fixed to splitter frame 24, and an upstanding ram face 
60 extending transversely of frame 24 and perpendicularly to its upper 
surface. A reinforcement member 62 extends between the ram face 60 and the 
mounting member 58 of each ram 56 to assure that the ram face 60 is firmly 
maintained in this generally vertical orientation. 
Notably, such ram 56 further includes a generally U-shaped retaining member 
64 extending about the entire periphery of ram face 60. Ram face 60 is 
recessed with respect to retaining member 64 to thus provide peripherally 
extending retaining lip 66 which projects perpendicularly from the surface 
of ram face 60. This unique configuration for each splitting ram 56 acts 
to retain a piece of wood in proper position on the upper surface of 
splitter frame 24 since retaining lip 66 will usually initially engage and 
penetrate of wood being split, thus resisting any tendency of the piece of 
wood to slip or become dislodged attendant to operation of hydraulic 
actuator 30. This retaining configuration of each ram 56 is particularly 
advantageous for splitting logs or pieces of wood having end surfaces 
which are not parallel to ram faces 60. For example, a log having a 
somewhat angled end surface, which of course may be the case in many 
instances, might otherwise tend to become dislodged from its proper 
position on frame 24 without the retaining action of lip 66. It will be 
appreciated that the peripherally extending nature of each lip 66 resists 
both sideways and upward movement of a piece of wood as it is subjected to 
splitting by coaction of wedge 44 and one of rams 56. 
From the foregoing, it will be observed that numerous modifications and 
variations can be effected without departing from the true spirit and 
scope of the novel concept of the present invention. It will be understood 
that no limitation with respect to the specific apparatus illustrated 
herein is intended or should be inferred. It is, of course, intended to 
cover by the appended claims all such modifications as fall within the 
scope of the claims.