Patent Publication Number: US-4258764-A

Title: Log splitting machine

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to wood splitters. An emerging energy consciousness has rendered such devices more popular. Splitters in which a ram for driving the wood into a cutter is driven by a hydraulic or air cylinder are commonly available on the market. 
     The drawback with such splitters is that they are somewhat slow and generally expensive. The prior art is repleat with various mechanical splitters, but none of them seem to be available in the market place. While the reasons for commercial failure of these mechanical devices are not known for certain, some of the drawbacks of such constructions can be appreciated by studying them. 
     For example the device disclosed in the patent to Power U.S. Pat. No. 946,705 discloses a crank driven ram to which an axe head is connected. The crank can be engaged with a pulley which is driven by a motor. However, this places a heavy load on the motor, particularly when the crank is first engaged. 
     The patents to Hauberg U.S. Pat. No. 1,231,525 and Schmidt U.S. Pat. No. 1,666,795 both disclose devices which operate continually. Continual operation may help to minimize overload problems, but such continual operation is of course dangerous. One would have to be very careful to avoid getting his hands and arms cut while trying to feed wood to a continually operating machine. 
     The relatively high cost and slow operation of air and hydraulic cylinder wood splitters and the past failure of mechanical alternatives illustrates the long felt need in this art for an effective mechanical splitter. 
     SUMMARY OF THE INVENTION 
     In the present invention, the ram of a wood splitter can be selectively engaged or disengaged with a motor driven flywheel to drive the wood against a cutter or to drive a cutter against the wood. The drive train between the motor and flywheel includes clutch means which effectively disengages the motor if the load on the flywheel becomes too great, thereby preventing motor overload. 
     The splitter employs a unique rack and pinion driven ram mounted on a beam which in turn is fitted with wheels and a hitch so that the entire device is portable. 
     These and other objects, advantages and features of the invention will be more fully understood and appreciated by reference to the written specification and appended drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevational view of a wood splitter made in accordance with the present invention; 
     FIG. 2 is a fragmentary side elevational view with the motor, cover and wood holding frame removed; 
     FIG. 3 is top plan view of the splitter with the motor, cover and wood holder frame removed; 
     FIG. 4 is a slightly elevated perspective view of the mechanism for activating the ram; 
     FIG. 5 is an elevated perspective view of the clutch for engaging and disengaging with the flywheel; 
     FIG. 6 is an elevated perspective view of the weighted idler which acts as an overload clutch to prevent the motor from being overloaded, and 
     FIG. 7 is a top plan view of the splitter. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the preferred embodiment, the wood splitter 1 (FIGS. 1-3) of the present invention comprises a ram 10 slidably mounted on an elongated beam 2 for ramming a piece of wood against a cutter 20. Ram 10 can be selectively engaged or disengaged from flywheel 30 which is driven by a motor 40. The drive train 50 includes a pivotally mounted weighted idler wheel 60 which serves as a clutch to effectively disengage motor 40 in the event that the load imposed upon flywheel 30 becomes too great. 
     Elongated beam 2 is a hollow steel beam which includes a hitch assembly 3 at the front end thereof (FIG. 1) and a leg 5 secured thereto towards the rear and extending downwardly therefrom and being joined to an axle assembly 6 for a pair of spaced wheels 7 such that the entire splitter is trailerable (FIGS. 1-3 and 7). Also secured to the front of beam 2 on the underside thereof is a bracket 9 which facilitates connection of hitch 3 to beam 2 and which also serves as a pivot mounting for a front stand 4. Stand 4 can be pivoted to an up position located generally parallel to and just beneath beam 2 and the interconnection between bracket 9 and standard 4 is such that standard 4 can be locked in said up position. 
     Most of the mechanism of splitter 1 is normally covered by a metal housing 8 (FIGS. 1 and 7). However, housing 8 has been shown removed, as has motor 40, in FIGS. 2 and 3 so that the internal workings of splitter 1 can be more fully understood and appreciated. 
     Ram 10 includes a head 11 which is a steel plate welded to the end of ram 10. Ram 10 itself is a steel bar with a rack 12 formed throughout most of its length from the rear end thereof approximately three quarters of the way towards the front. Ram 10 slides in a guide 13 which is formed by small metal plates welded to beam 2 on either side of ram 10. Ram 10 is also guided as it slides along beam 2 by means of a carriage assembly defined by a pair of carriage legs 14 which extend downwardly from head 11 on either side of beam 2 and by a carriage roller 15 extending therebetween beneath beam 2. 
     Welded to the rear of ram 10 is a kickout plate 17 which has a sloped leading edge 17a. Also welded thereto is a bracket 18a to which is secured a cable 18 which extends rearwardly from ram 10. Cable 18 extends over a pulley 16 which is rotatably mounted within the hollow interior of beam 2. Cable 16 then runs forwardly for distance approximately as long as ram 10. Its end is joined to a very heavy spring 19, which is comperable to a garage door spring, which is located within the hollow interior of beam 2 and which is joined to the front end of beam 2 by means of an eyebolt assembly 19a (FIG. 2). The tension in spring 19 can be adjusted by tightening or loosening the nut in eyebolt assembly 19a. The assembly of cable 18 and spring 19 and their related components serve as a return for ram 10 and pull it rearwardly to its starting position after it has completed a forward log splitting stroke. 
     Cutter 20 is a relatively thin hardened steel blade with a sharp leading edge 21. It is welded to the front of beam 2 so that it projects upwardly therefrom in line with the path which the head 11 of ram 10 follows. Head 11 will stop short of engagement with splitter 20, but the stroke of ram 10 is sufficiently great that a piece of wood placed on beam 2 will be split in two as it is driven over and past cutter 20. 
     Flywheel 30 comprises any heavy wheel. It has been found that a conventional automobile or trailer tire 33 mounted on a rim 34 is operable as flywheel 30. Flywheel 30 is mounted in a conventional manner on an axle 31. Axle 31 is in turn carried in conventional bearing assemblies 35 generally at either end thereof which in turn are mounted on steel plate platforms 36 which are welded to and which project laterally from either side of beam 2. Thus, axle 31 extends across beam 2 and across and above ram 10. 
     Flywheel 30 is fixedly joined to axle 31 so that it rotates with it. Also fixedly secured to axle 31 at a point on the inside of the bearing 35 which is closest to flywheel 31 is a clutch cog 32 (FIGS. 3 and 5). Clutch cog 32 forms one half of the clutch assembly which selectively engages or disengages ram 10 with flywheel 30. 
     Motor 40 is a conventional four cycle engine of approximately four horse power. A gasoline engine of the type manufactured by the type &#34;Tecumseh&#34; or by others is satisfactory for purposes of the present invention (FIGS. 1 and 7). Motor 40 is mounted on metal platform 42 which includes another metal brace 43 welded therebeneath. Both platform 42 and brace 43 are welded to the side of beam 2. 
     The drive train 50 between motor 40 and flywheel 30 can best be seen by reference to FIGS. 2 and 3. It comprises first a minor pulley 51 mounted on the motor drive shaft 41. It in turn drives a major pulley 52 by means of drive belt 54. Major pulley 52 is mounted on an axle 53 which is also common to a minor sprocket 55. A metal platform 58 is welded to the side of beam 2 and projects laterally therefrom. Major pulley axle 53 is rotatably carried in spaced bearings 59 which are mounted on platform 58. Minor sprocket 55 drives a major sprocket 56 by means of a chain 57 extending therebetween. Major sprocket 56 is fixedly mounted on one end of axle 31 whereby motor 40 drives flywheel 30 through drive train 50. 
     Weighted idler wheel 60 rests against the top of drive belt 54. It is rotably mounted on a small axle 60a which is carried on a generally L-shaped bracket 61 (FIGS. 3 and 6). The rearwardly extending leg of L-shaped bracket 61 is in turn welded to a sleeve 62 which is pivotally joined to a small axle 63 which in turn is welded to bracket 64 which is welded to beam 2. 
     The weight of idler wheel 60, including to some extent the weight of generally L-shaped leg 61 causes idler wheel 60 to bear down on belt 64 just sufficiently to enable motor 40 to rotate flywheel 30 through drive train 50. When there is no load on flywheel 30, there is very little slippage on belt 54 and motor 40 brings flywheel 30 up to speed relatively quickly. In the event of an overload, however, idler wheel 60 is sufficiently light that minor drive pulley 51 readily slides with respect to belt 54 thereby preventing motor 40 from being overloaded. 
     The clutch and drive linkage between flywheel 30 and ram 10 comprises first a pinion 70 which is rotatably and slidably carried on fly wheel axle 31 (FIGS. 3, 4 and 5). Pinion 70 can be shifted from left to right on axle 31. However, if preferably is always in engagement with rack 12 of ram 10. Welded to one side of pinion 70 is a clutch cog 71 which is designed for clutching engagement with clutch cog 32. Thus when pinion 70 and clutch cog 71 are shifted towards clutch cog 32, clutch cog 71 and 32 engage, thereby causing pinion 70 to rotate with flywheel 30, which in turn drives rack 12 and ram 10 forwardly. 
     The control mechanism for shifting pinion 70 and clutch cog 71 begins with a pair of radial pinion guide plates 72 which are also fixedly secured to pinion 70 on the side opposite cog 71 and which are spaced from one another slightly (FIG. 4). Pinion guide plates 72 rotate and shift with pinion 70 and clutch cog 71. 
     Plates 72, pinion 70 and clutch cog 71 are shifted by means of pinion guide levers 81 which project downwardly to either side of guide plates 72 and which include cam roller bearings 82 projecting inwardly towards one another and into the space between guide plates 72. Pinion guide levers 81 are in turn fixedly mounted on a control shaft 80 which extends above and generally parallel to beam 2 (FIGS. 2 and 4). Control shaft 80 is pivotally mounted at one end in a front standard 86 and at the other end in a rear standard 87. Front standard 86 is welded to one of the projecting platforms 36 (i.e. that on the side of beam 2 which is opposite flywheel 30). Rear standard 87 is welded to and projects upwardly from platform 58 which serves as the mounting platform for major pulley axal 53 of drive train 50. 
     Also fixedly secured to and projecting upwardly from control shaft 80 is a handle lever 83. By pulling handle lever 83 to one side, one rotates control shaft 80 and thereby pivots guide levers 81. This in turn causes guide plates 72 to shift towards clutch cog 32, which shifts clutch cog 71 into engagement with clutch cog 72. A return spring 84 is secured at one end to handle lever 83 and at the other end to platform 58 so as to pull handle 83 back to its original position when pressure from handle 83 is released, thereby shifting clutch cog 71 out of engagement with clutch cog 32. 
     Also fixedly secured to control shaft 80 is a downwardly projecting kick out lever 85 (FIGS. 2 and 4). It includes an enlargement 85a on the bottom end thereof (FIG. 2). The enlarged end 85a of kick out lever 85 is in alignment with a kick out plunger 90 mounted in a mounting bracket 92 which is secured to platform 36 on the side of beam 2 away from flywheel 30 (FIG. 4). The tip of kick out plunger 90 is in alignment with the leading edge 17a of kick out plate 17 on the rear of ram 10. Thus as the sloped leading edge of kick out plate 17 engages the tip of plunger 90 (FIG. 4), plunger 90 is gradually pushed away from ram 10 and the head 91 of plunger 90 in turn engages the enlarged end 85a of kick out lever 85 so as to push lever 85 laterally away from ram 10. This pivots control rod 80 which in turn pivots guide levers 81, which in turn shifts guide plates 72, pinion 70 and clutch cog 71 away from clutch cog 72, thereby causing the clutch cogs to disengage and allowing ram 10 to be returned by the action of spring 19. Thus in spite of an operator holding lever 83 over, the system automatically disengages at the end of the stroke of ram 10 by means of the interaction kick out plate 17, kick out plunger 90 and kick out lever 85. 
     A pair of wood guide rails 100 are mounted on either side of beam 2 and project just slightly above the level of beam 2 (FIGS. 1 and 7). These help hold a piece of wood in place on beam 2 between the head 11 or ram 10 and the cutting edge 21 of cutter 20. To help prevent a piece of wood from riding up over cutter 20, a wood hold down arm 101 is pivotally mounted to housing 8 at one end so that its free end pivots up and down over beam 2. A handle 102 projects upwardly from hold down 101. By placing a piece of wood under hold down arm 101 and applying pressure with one hand against handle 102, one can minimize the chances of a piece of wood riding up as it is forced against cutter 20. Further, safety can be facilitated by securing a shroud to hold down arm 101 such that the piece of wood and the cutter 20 are shrouded during the actual splitting operation. 
     In operation, the user starts the motor 40 which in turn rotates flywheel 30 through drive train 50. The user grasps handle 102 and lifts hold down arm 101. He then places a small log or piece of wood on beam 2 between the wood guide rails 100. He then pulls handle 83 towards him. This pivots control shaft 80 which in turn pivots guide levers 81 which in turn shift guide plates 72, pinion 70 and clutch cog 71 towards clutch cog 32. Clutch cog 71 is thus forced into engagement with clutch cog 32 and the rotation of flywheel 30 causes rotation of pinion 70. Rotation of pinion 70 in turn drives rack 12 and ram 10 forwardly so as to push the block of wood into and past cutter 20, thereby splitting it. 
     When ram 10 first begins to push a block of wood against cutter 20, a heavy surge load is placed on the system which is absorbed by the inertia of flywheel 30. However, if the load is too great, it might stall motor 40 and cause damage, but for the action of pivotally mounted idler 60 which is sufficiently light that minor pulley wheel 51 on motor output shaft 41 slips with respect to belt 54, thereby preventing an overload in spite of the loads imposed on flywheel 30. 
     As ram 10 nears the end of its stroke, the leading sloped edge 17a of kick out plate 17 engages the tip of kick out plunger 91 and drives it laterally away from ram 10. It in turn pushes kick out lever 85 over, which pivots control shaft 80 and guide levers 81. This pivoting action pulls guide plates 72, pinion 70 and cog 71 away from clutch cog 32, thereby causing clutch cog 71 and 32 to disengage. Upon such disengagement, return spring 19 pulls on cable 18 and pulls ram 10 back to its original position. Pinion 70 is simply rotated in reverse as ram 10 returns. 
     The entire splitter 1 is highly portable. Front stand 4 can be rotated in an up position and hitch 3 can be secured to a trailer hitch on a vehicle. Splitter 1 then trails along behind the vehicle. Of course, it is understood that the above is merely a preferred embodiment of the invention and that various changes and alterations can be made without departing from the spirit and broader aspects thereof as set forth in the appended claims which are to be interpretted in accordance with the scope and content of the prior art and the doctrine of equivalents.