Claims:
I claim
1. Agricultural irrigation apparatus including, in combination, a frame; plural wheel means carried by said frame for enabling translational movement of said frame thereby; means for coupling to an external pressured water delivery hose; winch means mounted to said frame and including a revolvable winch drum, a cable wound thereon and constructed for anchoring to stationary field structure, and an input mechanical drive coupled to said winch drum; a fluid motor having a fluid inlet coupled to said coupling means, a fluid outlet, and rotary mechanical output means coupled to said input mechanical drive of said winch means for winding said cable upon said winch drum; water delivery structure coupled to said fluid outlet; fluid bypass means coupled across said fluid motor for shunting fluid therearound; control means for metering fluid-flow through said fluid bypass means; and means coupled to said control means and responsive to the condition of a predetermined length of cable remaining unwound upon said winch drum for actuating said control means, whereby to shunt all incoming fluid through said bypass means and around said fluid motor and thereby stop said fluid motor and winch drum revolvement.
2. The apparatus of claim 1 wherein said winch means is of the selectable free-spooling type.
3. The structure of claim 1 wherein said cable includes an abutment proximate its outer end, said appartus including lever means pivoted to said frame, linkage intercoupling said lever means with said control means, said cable being oriented and said abutment being constructed for said abutment to engage said lever means and thereby pivot the same, whereby to actuate said control means.
4. The apparatus of claim 1 wherein said control means is adjustable for varying the amount of fluid bypassing said motor under winch drive conditions.
5. The apparatus of claim 1 wherein said winch means includes braking means for automatically braking the same at times when said fluid motor is in a quiescent state. of said curved portion and said water delivery system.
6. Agricultural irrigation apparatus including, in combination, a frame; plural wheel means carried by said frame for enabling translation movment of said frame thereby; means for coupling to an external pressured-water delivery hose; winch means mounted to said frame and including a revolvable winch drum, a cable wound thereon and constructed for anchoring to stationary field structure, and an input mechanical drive coupled to said winch drum; a fluid motor having a fluid inlet coupled to said coupling means, a fluid outlet, and rotary mechanical output means coupled to said input mechanical drive of said winch means for winding said cable upon said winch drum; water delivery structure coupled to said fluid outlet; fluid bypass means coupled across said fluid motor for shunting fluid therearound; control means for metering fluid-flow through said fluid bypass means; and means coupled to said control means and responsive to the condition of a predetermined length of cable remaining unwound upon said winch drum for actuating said control means, whereby to shunt all incoming fluid through said bypass means and around said fluid motor amd thereby stop said fluid motor and winch drum revolvement, wherein said cable includes an abutment proximate its outer end, lever means pivoted to said frame, linkage intercoupling said lever means with said control means, said cable being oriented and said abutment being constructed for said abutment to engage said lever means and thereby pivot the same, whereby to actuate said control means, said lever means including a pair of coplanar sheaves, said cable passing between said sheaves, said abutment beng constructed to abuttingly displace said sheaves and hence said lever means.
7. Agricultural irrigation apparatus including, in combination, a frame; plural wheel means carried by said frame for enabling translational movement of said frame thereby; means for coupling to an external pressured-water delivery hose; winch means mounted to said frame and including a revolvable winch drum, a cable wound thereon and constructed for anchoring to stationary field structure, and an input mechanical drive coupled to said winch drum; a fluid motor having a fluid inlet coupled to said coupling means, a fluid outlet, and rotary mechanical output means coupled to said imput mechanical drive of said winch means for winding said cable upon said winch drum; water delivery structure coupled to said fluid outlet; fluid bypass means coupled across said fluid motor for shunting fluid therearound; control means for metering fluid flow through said fluid bypass means; and means coupled to said control means and responsive to the condition of a predetermined length of cable remaining unwound upon said winch drum for actuating said control means, whereby to shunt all incoming fluid through said bypass means and around said fluid motor and thereby stop said fluid motor and winch drum revolvement, wherein said winch means includes braking means for automatically braking the same at times when said fluid motor is in a quiescent state, and wherein said braking means comprises brake pad structure pivoted to said frame, brake cable means secured to said brake pad structure, a pulley block pivoted to said frame and secured to said brake cable means, said winch cable passing through said pulley block in a manner to pivotally displace the same upon the presence of tension in said winch cable, owing to revolvement of said winch drum and travel of said apparatus, whereby to pull said brake cable means and thereby release said brakes.
8. The apparatus of claim 7 wherein said braking means are spring biased toward brake-set condition.
9. The apparatus of claim 7 wherein said frame includes means for selectively releasing said braking means, for transport.
10. Agricultural irrigation apparatus including, in combination, a wheel-carrying horizontal frame, said frame including a horizontal, curved rearward portion having a longitudinally oriented water supply input; a water delivery system upstanding from and mounted to said frame; means for powering said frame mounted thereto; and conduit means intercoupling said curved rearward portion to said water delivery system.
11. Agricultural irrigation apparatus including, in combination, a wheel-carrying frame, said frame including a curved rearward portion having a water supply input; a water delivery system upstanding from and mounted to said frame; means for powering said frame mounted thereto; and conduit means intercoupling said curved rearward portion to said water delivery system, said frame being essentially rectangular in form, said curved portion having a rearwardly extending U-configuration defining two fluid-flow branches, transverse brace means secured to said frame and bracing said upstanding delivery system, at least a portion of said brace means comprising conduit communicating with one branch of said curved portion, bypass valve means interposed between said portion of said brace means and said one branch, and fluid motor means interposed between the remaining branch of said curved portion and said water delivery system.
Description:
The present invention relates to creeper-type irrigation units and, more particularly, to a new and improved fluid driven winch drive type unit the improvements and advantages of which shall be described hereinafter in detail.
In the past, a number of different types of moving irrigation apparatus for farm use have been devised. Those of which the inventor is aware have proved deficient in a number of respects as to versatility in operation, automatic braking upon the application of water pressure and also at run termination, and so forth.
The present invention relies upon the concept of a generally rectangular frame having four wheels, two on each side. The frame is made of sufficiently strong material as to be able to withstand all anticipated loads, e.g., hose sizes and anticipated pressure surges; in addition, incoming water from an attached hose is routed directly through a portion of the frame itself and through bracing to an upstanding central distribution system. Adjustable bypass valve means and also a water-pressure-to-mechanical-torque convertor are utilized to supply both water to the distribution system but also to apply torque to a self-contained winch. The winch may be set either to free-spool condition, so as to permit a winch cable to be easily withdrawn from the winch proper, or to drive condition such that the winch is positively coupled back to the drive leading from the convertor as aforesaid, so that revolvement of the winch and winding up of the winch cable will automatically cause the unit to progress forwardly. The winch drive is much preferred over supplying torque to the wheels carried by the frame, since there is, first, a direct pulling to a predetermined destination i.e. "deadman," second, the terrain might be muddy or slippery, and third, vastly greater amounts of torque would have to be supplied at the wheels to achieve a similar movement of the frame.
The unit includes braking means that can be released during transit of the unit, that are automatically applied at and prior to the application of water pressure to the inlet connection of the frame, ahd likewise that are released upon unit movement and then re-applied upon reaching a predetermined point of travel thereof.
The apparatus as described herein is designed to be fully capable of creeping forwardly along its run and in addition, to dragging a standard agricultural hose having an inside diameter of 41/2 inches, a length of 660 feet and a weight of 500 pounds. The unit will likewise withstand a line pressure connection of 100 psi, with 80 to 95 pounds pressure at the nozzle discharging from 400 to 900 gallons per minute.
Accordingly, a principal object of the present invention is to provide a new and improved, creeper-type irrigation apparatus.
A further object is to provide water spraying apparatus which contains a frame a portion of which conducts fluids leading to a water-pressure-to-mechanical-torque convertor.
A further object is to provide, in water spraying apparatus, suitable braking means with associated structure effectively applying the brakes on termination of a given run of the unit.
A further object is to provide means for shunting fluid flow around the convertor automatically upon the completion of a travel by the unit.
A further object is to provide creeper-type agricultural sprayer apparatus wherein structure is provided for automatically applying brakes and terminating torque input to a self-contained winch system of creeper-type sprayer apparatus.
A further object is to provide manually operable brake release means to accommodate apparatus of the type described for transit.
An additional object is to provide creeper-type irriga-tion apparatus incorporating a water turbine drive, with appro-priate bypass valve means such that the driving torque applied to the unit can be varied.
The features of the present invention may best be understood by reference to the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a plan view of one embodiment of the irrigation apparatus of the present invention.
FIG. 2 is a side elevation of the structure illustrated in FIG. 1.
FIG. 3 is a fragmentary perspective view of the rear right-hand portion of the structure of FIG. 1, to the bottom left of the page.
FIG. 4 is a section taken along the line 4--4 in FIG. 1.
FIG. 5 is an enlarged perspective view of a bellcrank mounted to a forward portion of the frame in FIGS. 1 and 2.
FIG. 6 is a continuation of the structure of FIG. 1 of the right-hand side thereof, showing the tongue portion and braking structure actuator of the invention.
FIG. 7 is a continuation of the forward portion of the structure of FIG. 2, being a contamination thereof at the right-hand side of FIG. 2.
FIG. 8 is a fragmentary view of the structure of FIG. 7 wherein the unit has completed its course of travel toward the deadman or anchor in the field, the deadman and cable combination including means for automatically actuating the equipment such that brakes are applied and drive torque is terminated.
FIG. 9 is a fragmentary side elevation, partially broken away, of a pulley unit incorporated in the central portion of FIG. 7.
FIG. 10 is a front elevation of certain composite lever structure illustrated in FIG. 7.
FIG. 11 is a section taken along the line 11--11 in FIG. 9.
FIG. 12 is a fragmentary, left-side elevation taken along the line 12--12 in FIG. 10.
FIG. 13 is an enlarged detail of the bypass valve of FIG. 1 wherein the actuating handle or linkage thereof has been changed from closed to open condition.
FIG. 14 is a fragmentary perspective view of certain brake-dog structure which may be used in releasing the brakes, for unit travel.
FIG. 15 is a fragmentary plan view of a structure essentialy identical to that shown in FIGS. 1 and 6, but which has a rear portion modified to incorporate a fluid turbine itself containing an adjustable bypass valve construction.
FIG. 16 is a side elevation of the structure shown in FIG. 15.
FIG. 17 is a fragmentary perspective view of the structure of FIG. 15 and is similar to that shown in FIG. 3.
FIG. 18 illustrates the control handle in operative position.
FIG. 19 illustrates the control handle in bypass position.
In FIGS. 1 and 2 hose coupling unit 10 is connected to and interiorly communicates with hollow frame-conducit portion 11 which serves in effect as a water-flow divider. Hollow structural member 12 is connected and communicates with the latter and proceeds forwardly to constitute a portion of frame 13. Structural member 12 may be partitioned at 14 or otherwise constructed such that water flow through lower branch A, as indicated, will proceed upwardly and inwardly via brace conduit 15. The latter is welded to and otherwise communicates with the interior of member 12.
Frame member 16 may be solid or closed-ended and is welded or otherwise secured at 17 to branch B of hollow conduit frame 11. Frame member 16 likewise proceeds forwardly, with frame members 12 and 16 being joined to a structural receptacle 18, the latter receiving and preferably being affixed to tongue 19.
Water-pressure-to-mechanical-torque convertor 20 may comprise simply a water turbine or fluid motor and has its input side 21 operably connected to member 11 as indicated, with the output of the water turbine at W' being welded to discharge conduit 22 and communicating with the brace-conduit 15.
The riser 23, see FIG. 3, extends upwardly to its attachment flange 24, and the same is used to mount a revolving spray unit 25 thereto. The latter is conventional in construction and may take the form of the high-pressure, high-volume discharge sprayer or gun known under the tradename Big Gun. Convertor 20 has its conventional rotor output at 26 connected via flexible or sleeve coupling 27 to transmission 28. The latter is connected via a conventional gear-reduction gearbox 29 to conventionl winch drum 30. Winch drum 30 may be conventional in form and include a conventional clutch 31 adapted for free-spooling. Thus, upon the movement of clutch lever 32, the winch drum 30 may be brought either into or out of engagement with its drive via gearbox 29, in a conventional manner. Braces 33 and 34 are tied to frame 13 and support the winch drum unit. Brackets 35 and 36 are welded to frame 13 and include upstanding pivots 37 and 38 for pivotally receiving brake levers 39 and 30. Each of the brake levers 39 and 40 is provided with a brake shoe 41, 42, the latter prferably taking the form of a friction pad such as a rubber pad backed by metal plate 43, 44. Tension springs 45 and 46 are secured between levers 39 and 40 and respective eye-bolts 47 and 48 which are respectively attached to the forwardly extending support braces 33 and 34. The function of springs 45 and 46 is to keep the brake shoes or friction pads 41 and 42 against the respectiv wheels W in the absence of the application of tension to brake lines 49 and 50. As to the latter, the same may comprise ropes, cables, or other elongate, flexible connectors. Elongate connector 51 will generally comprise a conventional twisted-wire winch cable and will be wrapped around and anchored to the winch drum 30 in the manner shown in FIG. 1.
Adequate bracing may be supplied the structure as at brace 52 to the rear of the unit in FIG. 1 and also medial brace 53, disposed centrally with respect to the unit. Four wheels W will be supplied to the unit U, in general, with two of the wheels being shown in dotted line in FIG. 1 but the opposite wheel mounts at W" merely being indicated.
Of importance is the interpositioning of bypass valve 54 within the frame conduit structure 12. Thus, in reality, the hollow structural member 12 may comprise in fact two lengths of conduit 55 and 56 which are joined together and communicate with bypass valve 54. The bypass valve 54 may be of standard design and include a butterfly valve interior provided with handle 57. Handle 57 may have a pivoted, interiorly threaded collar 58 which threads onto the threaded portion 59 of shaft 60. Shaft 60 is provided with a crank handle 61; tubular lever 62 pivotally receives shaft 60 via retainer nut 63 and includes a pivot aperture at 64 receiving upstanding pin 65. Upstanding pin 65 comprises a pivot journal for arm 66. Arms 66 and 67 radially extend in opposite directions from center post 68, of bell-crank E, see FIG. 5. Center post 68 may be tubular in construction, if desired, and may be mounted over an upstanding pin 69 welded to frame 13. In any event, the structure of FIG. 8 will constitute a bell-crank in that an axial movement of lever 70 to the right in FIG. 1 -- the same being pivoted by pin 71 to lever 67 -- will simultaneously effect a thrusting to the left of lever 62 and, accordingly, a movement of handle 57 such that there is a tendency to open the bypass valve at 54.
FIG. 6 is an extension of FIG. 1, illustrating the tongue 19 proceeding forwardly from box 18. Likewise, FIG. 7 is an extension of the structure shown in FIG. 2.
In resuming a consideration of the structures of FIGS. 1, 2, 6 and 7, it will be seen that the connecting bracket 72 is bolted to tongue 19 by straps 73 and 74 and the provision of bolts 75 and 76. The rearward bolt, 76, see FIG. 7, may in effect serve as a pivot or a fulcrum for composite lever 77. The latter is secured to the lever of tie-rod 70 by means of bolt 78 passing through tie-rod knuckle 86. Tension spring 79 is secured by eye-bolt 80 to tongue 19, see FIG. 7, pulling the upper portion of composite lever 77 forwardly. The forward end of spring 79 is secured to an eye-bolt 81 which is anchored by nut means 82 to the cross-brace 83 of composite lever 77. The latter includes upstanding lever members 84 and 85 which include the bolt means 78 for connecting the bifurcated or knuckle end 86 of lever 70 to such composite lever 77. The lower ends of members 83 and 84 are welded to an open housing 87 including a pair of journaled sheaves 88. Cable 51 passes in the direction shown in FIG. 7. Elongated connector or cable 51 proceeds forwardly through the sheaves 88, that are centrally there-between, and is anchored to a "deadman" 89 such as a pole, an anchor, a truck, or other stationary or semi-stationary means. Vice grips, a fixed collar or other suitable means at 90 is secured to and about the elongate connector 51 such that the same will not slip in either direction.
The tongue 19 has a hollow interior and includes a horizontal pivot bolt 91 secured by nut 92. Pivot bolt 91 mounts a pulley member or pulley block 93 which simply comprises a box-type housing 94, open at opposite extremities, and provided with journaled pulleys 95 and 96. The same may be journaled in place by pin 97. A horseshoe-type connector 98 may likewise be provided in the box construction. It will be noted that solely pivot bolt 91 proceeds through the tongue construction, see FIG. 6. Accordingly, the pulley housing unit is free to be rotationally displaced solely about its pivot bolt 91.
FIG. 7 shows the condition where the unit is travelling toward deadman 89. Cable 99 is tied to brake release cables 49 and 50 and routes over pulley 99' to member 98.
In operation, the unit shown in FIG. 1 is positioned as desired on the ground, the water hose being connected to coupling 10. Prior to the turning on of the water clutch lever 32 will be actuated so as to free-spool the winch drum 30, enabling calbe 51 to be drawn outwardly therefrom and attached to suitable deadman as at 89 in FIG. 8. Thus, the elonate connector or cable 51 will be stretched clear across the field or a portion of the field which is to be watered. At this point, no tension will be supplied the brake calbes 49 so that springs 45 and 46 will be operative to apply pressure to the brake pads against the wheels or tires at W. This is because the levers 39 and 40 are fulcrumed about pins 37 and 38, with the springs appearing on one side of the fulcrum and the brake pads appearing essentially on the other side of the fulcrum.
At this point, the water is turned on and the valve 54 is opened by the adjustment of crank 61. It will be noted that crank 61 serves with its threaded collar 58 as a manually adjustable speed control, since the same controls the volume of water proceeding through bypass valve 54 to the water gun and, hence, controls the flow through water turbine or convertor 20.
It is to be noted taht the initial force of the water through the system does not tend to move the system since the brakes have already been locked in place by the action before mentioned
The water proceeding along route B and through the water turbine 20 turns the output drive of the water turbine which is translated through coupling 27 and the gear reduction system to the winch drum at 30. Since the clutch handle 32 will have been previously returned to a non-free-spool condition, then the winch drum will commence to revolve and tend to wind up the elongate connector or cable 51. In doing so the winch drum in its revolvement draws the unit forwardly, owing to the anchoring of the deadman 89 in FIG. 7. It is noted that tension on the elongate connector 51 pivotally displaces the pulley strudture at 93 in FIGS. 7 and 9 in a counter-clockwise direction, thereby exerting a pulley action upon cable 99 and the brake cable release cables 49 and 50. This, in turn, draws the forward extremities of levers 39 and 40 inwardly so as to withdraw the brake or friction pads from the wheels, thus allowing the same to move freely forwardly.
When the unit has reached the end of its run, then fixed collar 90 disposed upon elongate connector 51 will engage the sheaves at 88, tending to pivot the composite lever 77 about pivot bolt 76 in a clockwise direction, see FIG. 8. Such an action exerts a pulling action to the right, see FIG. 7, upon lever 70. By virtue of this action and the effect of rotation of the bell-crank unit E including arms 66 and 67, there is a thrusting to the left of lever 62. This action tends to open bypass valve 54, shunting the water there-through to the sprinkler gun 25. The water turbine is hence "starved" of a water flow drive and so the unit U comes to a halt. The condition of stoppage of the unit, is illustrated in FIG. 8 wherein it is shown that the lever has been pivoted and the rear extremity of pulley unit 93 has been raised. It will be noted that the clockwise rotational displacement of the pulley unit 94 in FIG. 8 tends to reduce the tension in cable 99 and brake cables 49 and 50 as to permit the brakes to reset.
FIG. 3 illustrates a right side upper perspective of the rearward and right portion of the unit of FIG. 1. FIG. 4 is essentially, of course, a rear view and is taken along the section line 4--4 in FIG. 1.
FIG. 12 illustrates a detail, partially broken away, of the composite lever construction 77 in FIG. 10, a central portion thereof being broken away to disclose the eye-bolt 81 connecting to the spring 79 in FIG. 7. Spring 79 serves to keep the lever 77 displaced in a counter-clockwise direction.
FIG. 11 is simply a detail taken along the line 11--11 in FIG. 9, illustrating a representative pulley mounting that can be used relative to bolt 91.
In returning to a consideration of the operation of the unit, it will be seen that subsequent to the automatic stoppage of the unit as seen in FIG. 8, then the water supply may simply be turned off, the cable or elongate connector 51 disconnected from the deadman 89 used, and the deadman replaced to another position for a future watering path.
At this point it should be noted that structural features of the unit of FIGS. 1-12 provide for an automatic braking of the unit during the commencement of the application of water pressure thereto. Further, such water pressure operates not only to produce a spray but also to drive the unit, namely the winch drum thereof, but use of a water turbine as at 20. There is an essential advantage to the using of a winch drive here since, first, reliance is not had upon traction of the wheels but rather upon the positive winding up action of the winch itself to a predetermined goal pulley. It is well known in the art that wheel drives per se are quite unsatisfactory in areas where there is mud or other moisture; further, a much higher torque would have to be applied to the wheels than simply to the winch drum. Secondly, it is to be noted that there is an automatic regulation of bypass valve 54 so as to supply not only a control for the speed of the water turbine 20 but also an automatic shut-off thereof when the unit has reached its destination as shown in FIG. 8. It is to be noted that at the end of the run there is an automatic re-application of the brakes plus a shunting of the water through the bypass valve so that the water turbine will be ineffective to drive the unit further forwardly.
FIG. 13 is a detail of the bypass valve 54 in FIG. 1. Thus, the handle position (57) shown in FIG. 13 indicates a bypass valve "open" condition wherein the water turbine tends to shut-off; in the handle position shown at 57 in FIG. 1, the bypass valve is closed or more nearly closed.
For convenience purposes, there may be supplied dogs 100, pivoted at 101 to respective brackets 102, for holding outwardly levers 40 and 39 during transport of the unit so that the brakes at 41 and 42 will not be applied against the wheels. Brackets 102 will simply be mounted to the frame 13. When the desired location is reached, then the dogs will simply be manually pivoted upwardly and released, thus applying the brakes preparatory to turn-on of the water at the water hose connection at 10.
FIG. 9 is simply a side elevation, partially broken away, of the pulley unit 93 in FIG. 8, and FIG. 10 is a front view of the composite lever construction 77 including eye-bolt 81.
It will be recognized that there are in existence various convertors, e.g., water turbines htat have self-contained, manually selectable bypass valve features. A representative one is known in the trade as a Berkeley Water Motor, No.4B4MA, manufactured by the Berkeley Pump Company at Berkeley, Calif. Such may be purchased from any supplier, and one such water turbine is shown in FIGS. 15-19 at 103. Control 104 of water turbine 103 is a conventional handle or lever that can be pivoted from full-flow condition through the water turbine to no-flow condition therethrough and through the incorporated bypass valve. Thus, the rotor of the water turbine is actuated by the throw of lever 104 in one direction, but will be rendered inoperative during the throw of the lever in another direction. Dotted line 105 represents a linkage as between threaded shaft 106 and the lever control of the water turbine including the self-contained bypass unit.
In such event, frame member 11A in FIG. 15 may be partitioned at 107 and include a flow channel at 108 leading to the water turbine 103. See also FIGS. 16 and 17.
Structure 109 will simply comprise frame structure but not water conduit. Brace 52 will be supplied as well as additional frame structure as at 13A. It will be noted that there is no bypass valve disposed in line 13A; rather, the same simply comprises frame structure. Frame structure 110 and 111 are likewise solely frame structure, may be tubular, but are not water conducting. Rather, there will be a conduit 112 communicating with upstanding conduit 113 leading to the water gun or other water spray equipment utilized. Conduit 112 of course will include the composite output from the water turbine, that is, that passing through the self-contained rotor thereof and also that passing through the bypass.
FIGS. 18 and 19 illustrate that with various orientations of control lever or handle 104 the water turbine may be in fully operative condition, see FIG. 18, or water flow may bypass the operative portion of the turbine by being shunted therearound as in FIG. 19. Crank 61 will still be used of course to adjust the ratio of water going through the water turbine rotor as against the water passing through the bypass valve. Different settings may possibly be used to different water prssures.
The structure illustrated in FIGS. 15-19 operates essentially identical to that seen in FIGS. 1-14. The forward portion of the unit relative to FIG. 15 can be identical to that shown in FIG. 1.
While a water-turbine type of fluid motor or fluid-pressure-to-mechanical-torque convertor, is preferred for use in the present invention as at 20 in FIG. 1 and 103 in FIG. 15, by way of example, yet the present invention might also employ other types of fluid motors thereat such as those of the piston and of the rotary type. For convenience of terminology in the claims appended hereto, the term fluid motor as used therein will include all types of such convertors, namely water-turbine type motors, gear-type, rotary, piston-type and other fluid motors.
What is provided therefore is a winch-driven water spray agricultural unit that is water driven by virtue of water pressure. Automatic convertor shut-off and brake application is supplied upon the completion of the unit's run.
While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art the various changes and modifications which may be made without departing from the essential features of the present invention and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.