US 3319739 A
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P. W. MORSE SELF- PROPELLED AERIAL PLATFORM May 16, 1967 4 Sheets-Sheet 1 Filed May 27, 1965 INVENTOR. PETER W. MORSE BY f ATTORN May 1967 P. W. MORSE 3,319,739
SELF-PROPELLED AERIAL PLATFORM FIGZ INVENTOR. PETER W MORSE ATTORNEY May 16, 1967 P. w. MORSE SELFPROPELLED AERIAL PLATFORM 4 Sheets-Sheet 5 Filed May 27, 1965 INVENTOR. PETER W. MORSE I ATTORNEY y 16, 1967 P. w MORSE SELF-PROPELLED AERIAL PLATFORM 4 Sheets-Sheet 4 Filed May 27, 1965 INVENTOR. PETER W. MORSE United States Patent fiice 3,319,739 SELF-PROPELLED AERIAL PLATIFURM Peter W. Morse, 207 Arnold St, West Wrentham, Mass. @2093 Filed May 27, 1965, Ser. No. 459,318 3 Claims. (Cl. 1822) My present invention relates to aerial platforms and more particularly to a self-propelled mobile platform.
The principal object of the present invention is to provide a mobile aerial platform which permits the complete operation of the device by the workman on the platform in either raised or lowered position.
Another object of the present invention is to provide an aerial platform which is hydraulically operated in both the lifting and the drive mechanisms.
A further object of the present invention is to provide a self-propelled hydraulic platform which is actuated by separate hydraulic cylinders and valves connected by flexible steel cables to the control platform, thus eliminating cables and pulleys and reducing the amount of hydraulic piping necessary.
Another object of the present invention is to provide a self-propelled aerial platform with a simple hydraulic drive mechanism Which permits movement in all directions and eliminates the need for separate brakes.
A further object of the present invention is to provide a self-propelled aerial platform having a minimum number of readily assembled parts and which is simple in construction and easy and economical to manufacture and assemble.
With the above and other objects and advantageous features in view, my invention consists of a novel arrangement of parts more fully disclosed in the detailed description following, in conjunction with the accompanying drawings and more particularly defined in the appended claims.
In the drawings,
FIG. 1 is a perspective view of a self-propelled aerial platform embodying my present invention with the platform in raised position.
FIG. 2 is a perspective view, taken from the side, of the vehicle with the platform in lowered position.
FIG. 3 is a perspective view, taken from above, of the front portion of the device showing the drive mechanism.
FIG. 4 is a perspective view of the rear portion of the device showing the boom arm mounting.
FIG. 5 is a diagram of the hydraulic hookup.
Mobile self-propelled aerial platforms are normally designed for a wide variety of industrial and constructional work. However, they are particularly applicable to farm aerial work in orchards. By making the worker mobile, that is, lifting and swinging him in any direction, a considerable amount of time and effort is saved over the use of ladders. A self-propelled aerial platform permits one man to do the work of from two to four men. The present invention is designed to provide a self-propelled aerial platform which reduces the drive lift and control mechanisms to a minimum, while retaining and even increasing the capabilities of the device over similar devices now in use. One of the features of the device is the novel boom arm suspension permitting smooth easy lifting and controlled horizontal movement. There are no axles. The two driven wheels are each individually hydraulically driven thus permitting greater control and mobility. Furthermore, since a hydraulic system is being used, it is a simple matter to provide a safety feature that when the boom arm or wheels are at a standstill they are locked in position. If there is a power failure and the engine stops, the wheels remain locked in posi- 3,319,739 Patented May 16, 1967 tion. Thus there is no motion and everything is locked in position when the device is in neutral and not running. Separate brakes are not needed.
Referring more in detail to the drawings illustrating my invention, FIGS. 1 and 2 illustrate the device with the boom arm in both raised and lowered position. The mechanism is mounted on a horizontally positioned rectangular frame 10 preferably made of an Lbeam construction. The frame 10 comprises spaced parallel side rails 11, a transverse front rail portion 12, and a transverse rear rail portion 13. From each rear corner of the frame 10, a rail 14 extends .angularly upwardly and angularly inwardly, each terminating in an integral horizontal portion 15 which join at the rear pivot point 16. The side rails 11 are joined by spaced crossed strips 17, see FIG. 3, for supporting the various parts of the device hereinafter to be described. Angle irons 18, at each side, connect the side rails 11 with the tapered front rails 14 for additional strength, and the tapered front rails 14 are additionally connected by a cross bar 19.
The device is mounted on suitable rubber tire Wheels. The rear wheel 2t is rotatably mounted at the lower end of a short angular channel bar 21 terminating in a fiat horizontal portion 22 which is swivelly mounted in a hearing 23 mounted at the apex point 16 where the rails 15 meet. This permits free rotatable swivel movement of the rear wheel 2!}. Each front wheel 24 is rotatably mounted on a disc support 25 which is eccentrically fixed to a bar 26 bolted to the front rail 12, see FIG. 3. Each front wheel is driven through a sprocket chain 27 and sprocket wheel 28 mounted on a hydraulic motor 29. Each hydraulic motor on each front wheel is individually controlled. This permits driving one motor at a time to provide a turning movement. The hydraulic motors are of a conventional type providing approximately 3600 inch lbs. wheel torque on a 1500 lbs. hydraulic pressure. Power is necessary but speed is not. Therefore, the vehicle is capable of a maximum self-propelled speed of approximately three miles per hour.
The platform support is mounted towards the rear of the device. A heavy short vertical I-beam 31) is mounted on the cross beam 19, see FIGS. 2 and 4. A second and slightly longer vertical I-beam 31 is hinged to the front of the I-beam 30 at 32 and 33. This permits the beam 31 to swing on the hinges 32 and 33 through an arc of approximately 40. A boom arm 34 of hollow construction is provided with reinforced side plates 35 at the rear end which are pivotally mounted at 36 at the top of the boom arm 31. At the front end, the boom arm 34 is provided with reinforced side plates 37 which is pivotally mounted at 38 to vertical plates 39 supporting the horizontal platform 40. The top of the plates 39 are pivoted at 41 to a rod 42 extending in spaced parallel relation over the boom arm 34 to a pivoted point 43 on a vertical post 44 positioned behind the boom arm 31. With this arrangement, .as the boom arm moves upwardly, the rod 42 changes its angular position so that the platform is always retained in horizontal position regardless of whether it is raised as in FIG. 1 or lowered as in FIG. 2.
Raising and lowering of the boom arm is accomplished by a large hydraulic cylinder 45 having its piston pivotally mounted to the plates 35 at 46 forwardly of the boom arm pivot point 36. The bottom of the cylinder 45 is pivotally mounted at 47 to an angle support 48 extending from the bottom of the vertical boom arm I-beam 31. Angular motion of the I-beam 31 and its associated boom arm 34 and platform 40 is provided by a horizontally mounted cylinder 49. The cylinder 49 is mounted below a plate 50 covering the horizontal portions 15 of the rails at the rear. The piston 51 extending from the cylinder 49 is pivoted to the end of a triangular plate 52 extending from the side of the vertical I beam 31 as shown in FIG. 4. Thus the horizontal reciprocal movement of the piston 51 causes swinging movement of the I-beam 31 on its pivots 32 and 33. As stated hereinabove, the I-beam 31 can swing in an arc of approximately Power to operate the various units is supplied by the hydraulic unit shown in FIG. 3 and illustrated diagrammatically in FIG. 5. Only a comparatively small engine is required, the engine 53 being approximately nine horsepower. The engine 53 drives a pump 54 through the belts 55, the pump 54 delivering approximately ten gallons per minute. The outlet line 56 from the pump 54 carries the oil under pressure (approximately 1500 lbs. per square inch) through a relief valve 57 to a parallel stack valve 58. The parallel stack valve 58 has four sets of controls with a common pressure line and a common dump line. The outlet of the valve 58 connects through a line 59 to the oil reservoir 60. The oil reservoir 60 is connected through another line 61 back to the pump 54.
Now referring to FIG. 5, control of the four stations of the parallel stack valve 58 is by means of stainless steel cables of the Bowden type. The first cable 62 controlsthe first portion of the valve 58 which leads through lines 63 and 64 to one front wheel motor drive 29. The sec- 0nd cable 65 similarly controls the other front wheel bydraulic motor 29 through lines 66 and 67. It is not necessary to reverse the engine to reverse the unit. Movement of the cables 62 and 65 in one direction will cause the oil under pressure to fiow through one pair of lines and back through the other pair to turn the wheels so that the device moves forwardly, and movement in the opposite direction reverses the flow of the oil to reverse the motors 29 and reverse the unit. Neutral position locks the oil in the lines and thus locks the motors 29 and acts as a brake. Since there is no flow of oil through the lines when the valves are in neutral position, failure of the engine 53 will have no effect on the braking action of the motors 29.
The next cable control 68 controls the portion of the stack valve 58 which controls the lines 69 and 70 leading to the piston 49 for operating the horizontal position of the boom arm. And finally the cable 71 similarly controls the pressure flow to lines 72 and 73 for operating the piston 45 for raising and lowering the boom arm. With this hookup, it is unnecessary to have lengthy oil pressure lines leading directly to the end of the boom arm so that the operator can control the device. It is only necessary to bring the cables 62, 65, 68 and 71 up to the operator where he can move levers to move the unit forward or rearwardly to move one wheel and lock the other wheel for turning movement to raise and lower the boom arm and for swinging the boom arm in a 40 arc regardless of its vertical position.
If desired the parallel stack valve may be equipped with another station for connecting hydraulic power tools to the basic unit. However, it is well known that pneumatic pressure affords a quicker response in the operation of tools. To this end the unit may be supplied with a compressor motor 74 and tank 75 operated from the original motor 53 by the belt drive 76. Tools such as sprayers, pruning shears and similar tools can easily be operated by running the air lines to the platform. Recommended operating pressure is approximately to lbs. per square inch on the air compressor.
Now referring again to FIG. 2, a vertical plate 77 is mounted in spaced parallel relation in back of the valve 58. Each of the valve stations is connected through the plate 58 with a rigid tubular line 78 carrying the cables 62, 65, 68 and 71. These cables now extend beneath the front cross plate 19 and up through a triangular shield 79 mounted on the rear of the device above the rails 15. The cables now extend upwardly and into the hollow boom arm 34. From the boom arm 34 they extend upwardly along the vertical portions of the platform 40 to a lever control station 80. The platform itself is protected by guard rails 81. Similarly, the power tools 82 are connected by lines 83 to the compressor tank 75. The motor and belt drive mechanism is covered for protection by a shield 84.
With the parts assembled as hereinabove described, operation of the device is obvious. As can be seen in FIG. 2, the lowermost position of the boom arm places the platform virtually on the ground. The operator steps into the guard rail portion 31 on to the platform 40 and moves the lever which operates the cable 71. This controls all line pressure through the lines 72 and 73 to the cylinder 45 and piston 46 for raising the boom arm. When a desired height is reached the operator merely places the valve into neutral position locking the parts in the place where they have stopped. Now operation of the levers for operating the cables 62 and 65 will turn the front wheels 24 either forwardly or in reverse as desired. Also, operating just one of the cables and thus only one of the wheels will cause a turning movement. Note that in any event the rear wheel 20 merely operates as a caster. As can be seen in FIG. 1, the boom arm can then be raised and the operator can then move the lever for operating the cable 68 which controls pressure to the cylinder 49 and piston 51 for moving the boom arm horizontally to any desired position. The operator can then operate the pneumatic tools for either spraying, pruning or any other work desired. In the illustration in FIG. 1, the boom arm is illustrated as being used for work in an apple or similar tree. With the need for moving up and down a ladder and climbing trees eliminated, and the use of power tools, one workman can do a considerable amount of work with less effort than from two to four men. The small motor uses very little gasoline and develops a considerable amount of line pressure. By driving each front wheel independently axles and differentials are eliminated. The boom arm suspension provides a considerable amount of strength, the lift capacity being in the neighborhood of 500 lbs. The hydraulic system permits easy and finger tip control and movement in any direction without leaving the platform. The oil lines may be provided with check valves to ensure oil flow in one direction only. The use of the parallel stack valve ensures a lock in neutral position at each unit which not only ensures a safe locking action in the desired position, but ensures safety against power failure of the engine.
By the use of small I-beams rigidity and strength is provided to withstand the strain of lifting the boom arm. Note that although the boom arm is only provided with a 40 are horizontally over the front wheels 24, any greater are would be unsafe because it would cause a tipping of the unit. Such additional movement can only be possible if the unit is bolted down or provided with side supports. Since the various parts and valves are of conventional type and easily obtained, the device can be readily manufactured and assembled. Other advantages of the present invention will be readily apparent to a person skilled in the art.
1. A self-propelled aerial platform comprising a rectangular frame, a raised rearwardly extending portion extending from the rear edge of said frame, a supporting wheel swivelly mounted beneath the rear end of said extending portion, a drive wheel mounted on each side adjacent the front end of said frame, a fixed vertical mast extending from said rear raised portion of said frame, said mast comprising a vertically mounted I-beam, vertically spaced hinges on the front edge of said fixed I-beam, a second I-beam having complementary vertically spaced hinges mounted on said hinges in front of said fixed I- beam, said second I-beam having a horizontal hinge movement limited to 40 by the contact of the adjacent edges of said I-beams, a boom arm pivotally mounted adjacent the upper end of said second I-beam, a platform mounted on the other end of said boom arm, means for maintaining said platform in horizontal position in any vertical position of said boom arm, means for pivoting said boom arm vertically, said pivoting means comprising a hydraulic cylinder mounted on said second I-beam, the lower end of said cylinder being pivotally mounted adjacent the lower end of said second I-beam, and a piston extending from said cylinder and having its free end pivotally attached to said boom arm, means for swinging said boom arm horizontally on said hinged mounting, means for driving each front wheel independently, and means on said platform for controlling said pivoting, swinging and wheel driving means.
2. A self-propelled aerial platform as in claim 1, in which said horizontal swinging means comprises an arm extending laterally from one side of said second I-beam, a hydraulic cylinder horizontally mounted on said raised frame portion, a piston extending from said cylinder, the free end of said piston being pivotally attached to the outer end of said laterally extending arm.
3. A self-propelled aerial platform as in claim 1, in which a motor is mounted on said frame, a hydraulic pump is operatively connected to said motor, an oil reservoir is mounted on said frame, an oil line connects said reservoir with the inlet of said pump, and a line extends from said pump outlet to a plurality of control valves and from said valves back to said reservoir, said valves forming part of a parallel stack valve, said stack valve having individually controlled valve portions each controlling the operation of one of said pivoting, swinging and driving means.
References Cited by the Examiner UNITED STATES PATENTS 2,674,500 4/ 1954 Hukari 182-2 2,750,155 6/1956 Nixon 182-2 2,905,262 9/1959 Zwight 182-2 2,954,092 9/ 1960 Trump 182-2 2,980,667 2/1961 Bercaw 182-2 3,066,756 12/1962 Broderson 182-2 3,085,648 4/1963 Benedetto 182-2 3,127,952 4/1964 Baerg 182-2 3,156,313 11/1964 Peterson 182-2 20 REINALDO P. MACHADO, Primary Examiner.