US2907502A - Ballast discharge device - Google Patents

Description

Oct. 6, 1959 K. M. LANG BALLAST DISCHARGE DEVICE Filed April 29, 1957 INVENTOR.

KEITH M. LANG BY Kara/ k United States Patent @fice 2,907,502 Patented Oct. 6, 1959 2,907,502 BALLAST DISCHARGE DEVICE Keith M. Lang, Minneapolis, Minn, assignor to General Mills, Inc., a corporation of Delaware Application April 29, 1957, Serial No. 655,622 4 Claims. (Cl. 222-557) This invention relates generally to a ballast control system and more specifically to a ballast control system for discharging magnetically permeable shot type ballast.

Ballast control systems employ a variety of ballast materials depending upon the particular need requirement. In manned balloon flights the use of a metallic shot type ballast is utilized quite extensively. The shot type ballast consists of metal particles about one-eighth the size of air rifle pellets. These shot are usually made of steel or other metals with magnetic properties. The shot, unlike air rifle pellets, are not rounded but are largely irregular in shapeand have high hardness. Such irregularity and hardness in the shot makes it more difficult to control them when used as ballast.

A known ballast control system which has been employed heretofore has utilized an electromagnetic valve to discharge the shot. Disadvantages have been encountered in this type of unit however. One particular disadvantage is the use of an electrical source needed to energize a magnet. Further, on manned balloon flights a power failure would make ballasting diificult with the likelihood ofendangering the balloon personnel.

Having pointed out some of the disadvantages of prior devices it is therefore an object of the present invention to provide an improved mechanical shot type ballast control which can be manually actuated to discharge, at a predetermined flow rate, magnetically permeable ballast at the discretion of balloon flight personnel.

Another object of the invention is to provide an inexpensive, positive action, ballast control which will discharge irregularly shaped magnetically permeable ballast at known rates without endangering the lives of balloon flight personnel.

Other objects and advantages will become apparent in the following specification and the appended drawings in which: t

Figure 1 is a side elevational view of a balloon with a supporting structure suspended from its lower end;

Fig. 2 is an enlarged partial sectional perspective view of the gondola of Fig. 1; and showing details of the ballast control;

Fig. 3 is an isometric view like Fig. 2, showingthe unit with a supply of ballast;

Fig. 4 is a cross-sectional view of the ballast valve of Fig. 3; a

Fig. 5 is a sectional view showing the ballast build up on the top surface of a magnet mountedon the valve plate; and

Fig. 6 is an isometric of the ballast valve shown as an integral unit.

In planning a balloon flight many factors are taken into consideration-the design of the balloon, the altitude to which it will ascend, rate of ascent, the time it will remain aloft and the weight to be carried aloft. Included in the weight is the amount of ballast to be carried aloft. In computing the amount of ballast, the size of the balloon, the time .it'will remain aloft and weather conditions must be considered.

4 Due to the eflect of atmospheric thermodynamics, pressure changes at altitude over a period of time will cause expansion or contraction of the gas within the balloon which in turn causes it to ascend or descend from a given altitude. The ascension of the balloondue to expanding gases can be controlled by venting'the excess. gas. However descent of the balloon which may occur because of contraction of the gases due to pressure changes or a small rupture of the balloon, or the like, is controlled by the amount of ballast that is dropped. For example, if a balloon is to remain aloft for a period of eight (8) hours and during the eight hour period it is anticipated that due to contraction of the gases the balloon will lose 500 feet in altitude, it is then necessary to dischrage enough ballast to compensate for the contraction of the gases so that the balloon can maintain the prescribed altitude.

As shown in Fig. 1, during manned balloon flights a personnel carrier in the form of a gondola 2 is suspended beneath the balloon 4.

For illustration purposes the gondola 2 is shown as being separated into compartments 6 and 8. Compartment 6 is larger and its purpose is to support the flight personnel and equipment while compartment 8 has the provisional purpose of housing the ballast and ballast control valve.

Compartment 6 is not shown in complete detail but its design and position depend upon the number of flight personnel and their equipment to be carried therein.

Referring now to compartment 8. A floor or supporting structure 10 separates compartment 8 from compartment 6 and the ballast supply bin or hopper 12 is secured thereto. The supply hopper 12 extends downwardly from the floor l0 and is provided with an inclined lower surface 14 terminating in a vertical discharge spout 16 which isprovided with a flanged lip 18 extending normal thereto around its outeredge.

Secured to the lip 18 such as by screws 20 is a mechanical valve shown generally at 22. The valve 22 is provided with top and bottom support plates 24 and 26 which are located normal to the discharge spout 16. The top and bottom support plates 24 and 26 are held in a spaced relation with each other by being made an integral part of the discharge tube 16. p

A vertical shaft 28 is interposed between the support plates 24 and 26 near their ends opposite the discharge tube 16 and is press-fit mounted in suitable sealed ball bearings '38 and 40. The shaft 28 extends downwardly beneath the support plate 26 and is secured by a key 42 to a valve plate 44 which is positioned parallel to support plate 26. a

The valve plate 44 is identical in outward configuration to support plate 26 and by the provision of the key.42 is movable laterally by rotation of the shaft 28. The valve plate 44 is provided in its end subjacent the discharge tube 16 with a permanent type magnet (Alnico). 46 which is press-fitted into an opening 66. As can. be seen from the drawings when the valve plate 44 is positioned beneath the discharge tube 16 the magnet is in alignment with opening 36. When not dropping ballast the valve plate 44 is substantially aligned beneath the support plate 26. To maintain positioning of the valve plate 44 a spring 48 is provided and surrounds the shaft 28. The spring 48 is attached at its upper end in an opening 50 of the support plate 24. The other endof the spring 48 is attached to shaft 28 in opening 52. The action of the spring 48 is such that when the valve plate is manually moved from its normal position beneath the support plate 26, then upon release of plate 44 it will return to its normal position. In other words, valve plate 44 is spring closing. I

The valve plate 44 is provided with a vertical stop 54 which engages the support plate 26 to prevent misalignment of the valve plate when it is returned to positionbeneath the support plate 26.

The actuation of the valve plate 44 in the present embodiment is by the manual operation of a flexible cable] 58. The cable 58 is secured to a tab 60 on the valve plate 44 and extends upwardly through a conduit 61 to an actuator bar 62 in compartment 6. The conduit 6h is curved at its lower end so that the cable 58 is positioned substantially normal to and parallel with the valve plate 44. To open the valve plate 44 an operator within the compartment 6 lifts the actuator bar 62 of cable 58 to overcome the pressure of the spring 48. Upon release of the bar 62 the spring 28 once more returns the valve plate 44 to a normally closed position.

Referring now to the operation of the ballast control, the hopper 12 is filled with a supply of ballast pellets 64 and the valve plate 44 is in a normally closed position beneath the supporting plate 26. As the hopper 12 is filled through opening 30 ballast flows gravitationally into the pro-calibrated opening 36 of the discharge tube 16. The size of the discharge tube 16 will -vary in size depending upon the ballast flow rate requirement of the ballast that is to be discharged. As stated earlier in the specification, the individual ballast particles 64 are irregularly shaped and as they flow into the discharge tube 16 the lowermost particles 64a are attracted to the magnet 46. Tlhere the ballast particles 64a build up on the surface of the magnet 46. As can be seen in the drawings, the valve plate 44 is spaced from the supporting plate 26 by a spacer 27 which is integral with valve plate 44. The purpose of such spacing is to provide sufficient clearance between the valve plate 44 in its movement relative to the support plate 26 to prevent jamming of the particles.

When an operator Within compartment 6 elects to drop an amount of the ballast 64 he lifts the actuator bar 62 as above described, permitting the ballast within the discharge tube 16 to dropthrough the opening 36 and free of the gondola 2,. It is to be pointed out that While the magnet 46 is sufiicient to attract the lowermost particles 64a, the force applied to the valve plate 44 is sufi'icient to move the magnet 46 from beneath the discharge tube 16 even though a number of particles remain on magnet 46.

Under normal conditions an operator in discharging the ballast is concerned with the amount of ballast that is being released. Therefore immediate release of the actuator bar 62 allows the spring 48 to return the valve plate 44 to a closed position. A substantially predetermined amount of ballast will be released with each rapid opening and closing of the valve plate 44, and by counting the number of quick openings of the valve plate 44 the operator can multiply this by the known amount released with a single quick opening and determine the over-all amount of ballast discharged. 7

Should, however, the need arise, as in the case of a ruptured balloon he can by holding the valve plate .4 open-discharge the entire amount of ballast to lighten the loading of the balloon.

After a portion of ballast 64 has been released the remaining ballast in the hopper 12 continually refills the discharge tube 16.

Another embodiment of the valve is shown in Fig. 6. The support plates 24a and 2612 are cast integral With the discharge tube 16a. The valve plate 44a is attached to the shaft 28a in the manner previously described and is provided with an integral stop 54a. The spring 48 returns the valve plate 44a to a closed position and the valve operates as the embodiment of Fig. 2 described hereinabove.

However, with cast construction the mechanical failure of the various parts is minimized and the costs of manufacturirtg and assembling the unit are reduced.

in the art.' It is therefore my intention not to limit my invention to the particular form disclosed but cover all modifications and improvements falling within the scope .of my invention. v

Now, therefore, I claim:

1. In a non-jamming discharge device for discharging magnetically permeable particles, the combination including a supply hopper for said particles, a discharge tube means connected to said supply hopper for gravitationally discharging said particles therethrough, a valve plate provided with a permanent magnet pivotally mounted on said discharge tube means and movable between discharge and closed position, said permanent magnet substantially aligned with one end of said discharge tube means when said valve plate is in a closed position said valve plate and permanent magnet being spaced from said one end to an extent to exceed the maximum diameter of a magnetically permeable particle, said permanent magnet causing particles from the discharge tube means to collect thereon, thereby completing the closure of said valve when said valve plate is in the closed position.

2. In a ballast discharging device the combination including, a ballast supply hopper for gravitationally supplying ballast to a discharge :tube means, a discharge tube means connected to said hopper for the transmission of ballast therethrough, a movable valve plate pivotally mounted on said discharge tube means movable in a plane substantially normal to said-discharge tube means between a discharge and closed position, a magnetic means mounted on said valve plate and alignable with the outlet of said discharge tube when in said closed position for attraction of ballast thereto, whereby closure ofsaid valve plate maintains the ballast in said discharge tube means. I

3. In a discharge device for discharging ballast particles the combination including, a ballast particle supply hopper for supplying ballast particles, a discharge tube means connected to said hopper for the gravitational transmission of ballast therethrough, a movable valve: plate pivotally mounted on said discharge tube means and movable between a discharge and closed position,

said pivotally mounted valve plate located a spaced distance from the discharge end of said discharge tube means. of an extent to allow the maximum dimension of a ballast particle to pass under said discharge tube means upon pivoting of said valve plate, permanent magnet means integral with said valve plate and substantially alignable with said discharge tube when the valve plate is in the closed position, whereby closure of said valve plate maintains the ballast in said discharge tube and said permanent magnet attracts some of the ballast particles sufficient to close the spaced distance between the discharge end of the discharge tube means and said permanent magnet.

4. In a discharge device for discharging ballast particles the combination including a ballast particle supply hopper means provided with an outlet opening, a movable valve plate pivotally mountedon said hopper means and subjacent thereto, said valve plate being movable between a discharge and-a closed position, said pivotally mounted valve plate located a spaced distance from the opening of said supply hopper means of an extent to allow the maximum dimension of a ballast particle to pass between said opening and said movable valve plate, permanent magnet means integral with said valve plate and substantially alignable with said opening when the valve plate is in the closed position, whereby closureoi 'said valve plate maintains the ballast in said hopper means and said permanent magnet attracts some of the ballast particles sufficient to closethe spaced distance between theopening of said hopper means and said permanent magnet.

References Cited in the file of this patent UNITED STATES PATENTS

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