US2042739A - Powder bin discharge structure - Google Patents

Description

June 2, 1936. c. H. SMITH POWDER BIN DISCHARGE STRUCTURE Filed March 7 ATTORNEYS INVENTO Patented June 2, 1936 UNFTED STATES PATENT OFFICE POWDER BIN DISCHARGE STRUCTURE Application March 7, 1934, Serial No. 714,429

20 Claims.

This invention relates to powder bin discharge structure and is designed to control the discharge of powder and to maintain a constant ample flow during discharge. It consists in a bin provided with characteristic bridge-breaker structure, and in a powder bin attachment constituting a separate unit applicable to bins of various kinds and sizes and provided with bridge-breaker structure insertable into the taper opening of the bin hopper and with means of attachment to the bottom of the bin.

In the drawing in which the invention is illustrated as applied to powder bins of the travelling type:

Fig. 1 is a front elevation of an overhead travelling bin in position over a mixing machine to which powder is to be delivered, but which forms no part of the present invention.

Fig. 2 is a side elevation corresponding to Fig. 1.

Fig. 3 is a detail transverse vertical section through the bin hopper and the bin discharge structure.

Fig. 4 is a horizontal section on the line IV-IV, Fig. 3, and

Fig. 5 is a detail vertical section corresponding to Fig. 3, parts being broken away, illustrating the discharge position with the valve almost fully open.

Continuous uniform powder flow, difiicult to maintain because of the formation of powder bridges, is insured under ready control by individual operators as will appear from the following detail description.

The bins I, to which the invention is shown as applied, are of the overhead travelling type mounted for movement from the filling platform, not shown, to the place of discharge and resting, as by the lugs 2, upon the respective side and end carriage frame members 3, l, within which the bin is supported. The carriage has roller wheels 5 which run on spaced track girders 6, extending to the filling platform, and one set of which is driven through reducing gearing l, 8, by pulley 9 operated by hand rope or chain It which drives, in either direction, the axle l I mounted on the carriage and to which both it and the gears 1 are fast, gears 8 being fast to the adjacent wheels 5.

The structure is shown in Figs. 1 and 2 in its discharge location which is directly over the removable funnel l2 of the mixer I3 which forms no part of the instant invention.

Referring now to the remaining and detailed views in which is illustrated the preferred embodiment of the device, it will be seen that the discharge control structure is of such a nature that the bridge-breaker is supported thereby solely at the bottom of the conical hopper portion I 4 without obstruction thereof by any support within the bin itself. The discharge control structure may be constructed as an inde- 5 pendent removable and replaceable unit constituting a powder bin attachment having the bin mouth [5 whose out-turned flange I6 may, as shown, be secured to the flanged collar I! at the bottom of the hopper M by bolts l8 with an in- 10 termediate rubber or etc. gasket I 9 forming a moisture tight joint. The hub 20 upstanding out of the bin mouth and coaxial therewith is supported therefrom by spider arms 2|, which constitute the only fixed obstruction extending across the path of powder flow to the bin mouth discharge. This opening is commanded by a valve 22 shown in closed and open positions, respectively, in Figs. 3 and 5 and having let into its conical surface a valve seal gasket 23 of suitable somewhat yielding material, as rubber or leather, seating against the edge 24 of the bin mouth discharge so as to provide a moisture tight or hermetic closure to protect the powder as does the attachment joint above described. The spider 25 arms 2! are so located with reference to the bin. mouth discharge as to enable the operator, when the valve is open, to reach and remove a foreign obstruction which may get into the powder and be stopped by the spider arms. Several lumpbreaker pins 22' may be threaded into the valve body. This valve has a co-axial stem 25 shown as removably secured to it by cross bolts 26 and located within and threaded through the upstanding hub 20, the stem and hub being correspondingly screw-threaded at 2'! and 28 as shown. The otherwise open end at the bottom of the hub 29 is closed by a metal Washer 29 beneath which is a gasket 30 of suitable softer material, as leather, rubber or etc., the edges of both fitting a rabbet in the internal wall of the hub and being pushed into place and the soft gasket compressed by the bushing 3! itself fitting the shoulder of an adjacent rabbet in the hub end and held in place and to the spider structure by the Washers 32 and bolt heads 33 beneath them and making a powder-tight joint with the unthreaded lower end of the valve stem. Working in of powder through the bottom of the hub is thus prevented and the stem and its screw-threaded connection protected. The valve also carries a cylindrical guard 34 co-axial with the bin mouth and spaced therefrom and from which depends an inwardly inclined canvas shroud 35, which serves to direct the discharging powder to the funnel l2 or other destination, but which, owing to its flexibility, does not obstruct travel of the bin. This guard and shroud are secured to the valve preferably by the handle means 36, which is best made multiple, having radial arms 3? let into the grooved bottom of the valve at 38, the structure being held thereto by the bolted plate 39. The valve is thus mounted for rotation and for axial movement in opening and closing.

The upper end of the hub is reduced in diameter sufficiently to form at its base a shoulder fill on which rests rotatably a hollow bridgebreaker shaft M, which fits closely, but rotatably, the reduced portion of the hub. Bridge-breaker means, preferably the arms or pins 42 shown, are carried by the shaft at longitudinal intervals. In general, these are so constructed and located that they perform the bridge-breaking function throughout a substantial vertical height or zone, the arms being arranged in pairs whose members are diametrically opposite and which, in general, are oppositely inclined up and down respectively so as to operate in different and adjacent zones. The arms are preferably all located in a common plane, those at one side of the shaft being inclined downward and those at the other being inclined upward. The pins of the lowest pair immediately above the spider arms 2! are screw-threaded at 53 into a collar 45 fast to or integral with shaft 4! as by welding. It will be-noted that to avoid the spider arms one of these pins is not inclined downward but projects directly outward. The next pair of bridgebreaker members have at their inner ends hexed heads 55 and are screw-threaded at 46 into a fixed collar All and terminate in reduced pins 58, which project inward into a corresponding annular groove 49 in the exterior reduced surface of the hub 20, rotation of the bridge-breaker shaft being thus permitted but endwise movement prevented. The next pair of bridge-breaker arms is of like nature and similarly secured as indicated by use of the same reference numerals, but the reduced end portions 5?) project almost to the valve stem and serve a function shortly to be stated. The next pair is conveniently formed from a single piece of wire passing through the hollow shaft and having therein an intermediate horizontal portion 5! and having ends extending outward from the shaft and respectively inclined upward and downward. It will be observed that by reason of the deflection of the arms the lateral dimension, or diametrical spread, of each pair of arms is less than the total length of the arms themselves and that this spread increases as the pairs are located further outward on the hollow shaft, the extreme lateral or transverse dimension being greater than the diameter of the discharge opening or tapered end of the conical hopper into which the bridge-breaker shaft is introduced. The reverse inclination of the fixed arms allows and facilitates this notwithstanding the greater lateral dimension just referred to, but to permit a still wider lateral extension of the uppermost pair of arms 52, 52, they are foldably mounted on a head 53, which fits within and closes the upper end of the hollow shaft 4| and is bolted thereto. Each said arm may be turned upward and inward about its respective pivot pin 54 for insertion through the taper hole, but when free to do so the arms drop to the position of use, as shown in Fig. 3 wherein they rest against the seats 55 on the head 53.

Maintenance of a continuous even and. rapid powder fiow is of the greatest importance, and bridging of the powder in the hopper interferes with such flow. It is not necessary or desirable, however, to operate the bridge-breaker when the valve is closed, or only slightly open, 5 since undesirable packing and possible jamming of the powder would occur. The bridge-breaker and the valve in the instant construction while operatively connected are, as will shortly appear, so related that they do not move together until 10 .the valve has been opened almost to its maximum extent, or if preferred until it is completely open, the bridge-breaker not being brought into play until then. In fact if the powder does not bridge and the desired flow continues, it is 15 not necessary to operate the bridge-breaker at all. Accordingly a lost motion or deferred-action operative connection between the valve and the bridge-breaker is provided, the operation of the bridge-breaker being thus subordinated to the operation of the valve. In the illustrated structure this is accomplished by the following means: Valve stem carries a diametrical cross pin 55 projecting radially outward at both sides of the stem and which constitutes one of the 25 clutch members, the other being'the annular sleeve 57 having the diametrical clutch'groove 58, from which the pin is normally spaced in the direction of the length of the valve stem, the sleeve being prevented from turning, but permitted limited axial movement, by its cross slot 59 intowhich project the reduced ends 66 of the bolts 6! threaded through collar 52. Spring 63 beneath the sleeve 51 re-acting against it and the internal ends 50 of the adjacent pair of bridge-breaker arms urges the sleeve toward the pin 56, thus insuring the continued pressing of the sleeve 5'! yieldingly against the pin when rotation of the stem 25 and consequent downward axial progression in the opening of the valve brings the pin into contact with said sleeve and groove which does not occur until the valve has almost reached its limit of opening. The clutch members are then maintained in clutched relation and the bridge-breaker may be repeatedly swung back and forth about its axis, as found desirable by the attendant, without the necessity of complete or repeated rotation. The arrangement is such that the powder flow can be readily controlled by an attendant, as will be apparent, and the structure not only performs its intended functions, but protects the screwthreading of the hub and stem from powder and the powder against entrance of moisture when the valve is closed. The bin is provided with a cover tightly closed as by an arrangement of cams.

I claim:

1. Powder bin discharge structure comprising a bridge-breaker adapted to be supported within a powder bin on fixed structure at the bottom of the bin, and a valve commanding the discharge opening of the bin, operatively related to the bridge-breaker and having its stern threaded through a nut in said fixed structure, the threads 65 being enclosed against access of powder thereto.

2. A powder bin discharge control device comprising in combination a powder bin having a hopper bottom, a bin-mouth in communication with the discharge outlet from said bottom, a valve commanding the bin-mouth, means for opening and closing the valve, a bridge-breaker within the bin, and a deferred action clutch having clutch members respectively connected to the valve and to the bridge-breaker and relatively movable from an unclutched into a clutched relation after the valve has neared the limit of its opening movement.

3. A powder bin discharge control device comprising a powder bin having a hopper bottom, a bin-mouth therefor, a coaxial hub upstanding from the bin mouth, a valve commanding the bin-mouth and having its stem screw-threaded through said hub, a hollow bridge-breaker shaft rotatably mounted on said hub outside of the valve stem, and clutch members respectively connected to said valve stem and said shaft located in positions of axial separation when the valve is closed and subject to relative movement lengthwise of the shaft into clutched position after the valve has neared the limit of its opening movement.

4. A control device for powder bins as set forth in claim 2 in which the bin-mouth has a spider providing an internally screwthreaded hub or axial nut member, a valve commanding the bin-mouth and having the stem threaded through the hub or nut member, handle means for rotating said Valve and stem, a hollow enclosing shaft concentric with the valve stem, rotatably mounted on the hub member and excluding powder from the threads, bridge-breaker members carried by said shaft, a clutch member connected to said shaft and movable lengthwise of it, a companion clutch member carried by the valve stem and adapted for deferred coaction with the clutch member, and resilient means urging the first named clutch member toward clutching position and for maintaining the clutched relation when established.

5. A powder bin discharge control device comprising a powder bin having a hopper bottom, a bin-mouth therefor, a retaining shield spaced from and enclosing the bin-mouth and an enclosing shroud of flexible material depending from said shield, a valve commanding the binmouth and carrying said shield and shroud, a bridge-breaker carried by the bin-mouth, manual handle means exterior to the bin-mouth for opening and closing the valve, deferred action operative connections between the valve and the bridge-breaker having clutch members separated when the valve is in closed position, connected respectively to the valve and to the bridgebreaker and movable into clutched relation after the valve has neared the limit of its opening movement.

6. A powder bin attachment comprising a powder receiving and discharging bin-mouth adapted for attachment to the bin adjacent its discharge outlet, a valve commanding said mouth and carried thereby, means for opening and closing the valve, a bridge breaker upstanding from the binmouth for introduction into the bin through its discharge outlet and for location within the bin, and clutch connections between the valve and the bridge-breaker separated from each other in the closed position of the valve and timed for relative movement into clutched position after the valve has neared the limit of its opening movement.

7. An attachment for a powder bin of the hopper bottom type comprising an upstanding bridge-breaker having a greater maximum lateral dimension than the corresponding dimension of the taper end of the hopper bottom and insertable into the bin through said end, a valve controlling powder delivery from the bin, 21 support for said bridge-breaker and for said valve,

deferred action operative connections from the valve to said bridge-breaker, and manual operating means exterior to the bin for actuating the valve.

8. A powder bin attachment comprising a powder receiving and discharging bin-mouth adapted to be clamped to the bottom of the bin beneath and in communication with the bin, an internal spider carried by the bin-mouth and having an elongated upwardly extending hub, a valve commending the bin-mouth and having its stem upstanding from the valve and screw-threaded through the hub, a hollow shaft mounted rotatably on the hub coaxial therewith and exterior thereto and shutting off access of powder to the threads of said stem and hub, bridge-breaker members carried by said shaft, clutch members rotatable respectively with the valve stem and the shaft, and means for rotating said valve stem to open and close the valve and cause relative axial travel of said clutch members and, near the limit of valve opening movement, their mutual engagement and the consequent operation of the bridge-breaker.

9. A bin-mouth assembly adapted for incorporation in and attachment to a powder bin adjacent the discharge opening of its conical hopper and including a bin-mouth having rotatably mounted thereon a bridge-breaker shaft coaxial therewith and having at intervals lengthwise thereof opposed outwardly extending reversely inclined arms arranged in pairs, the pairs of arms relatively distant from the opening in the bottom of the bin having a radial spread greater than the diameter of the opening in the bottom of the bin and a total length in excess of their radial spread, a valve carried by the bin-mouth coaxially with said shaft, handle means carried by the valve for operating it, and clutch connections between the valve stem and the bridgeb-reaker shaft subject to relative axial movement by valve operation and timed relatively to the movement of the valve to be brought into clutched position only after the valve has neared the limit of its opening movement.

10. A bin-mouth assembly adapted for incorporation in and attachment to a powder bin adjacent the discharge opening of its conical hopper and including a bin-mouth provided with means for supporting co-axially therewith an upstanding bridge-breaker shaft having at intervals lengthwise thereof opposed outwardly extending arms arranged in pairs, the pair of arms furtherest distant from the outlet of the bin having a radial spread greater than the diameter of the opening in the taper end of the hopper, the arms of this uppermost pair being hinged to the bridgebreaker shaft for folding for purposes of insertion into the bin through the taper end of the hopper and being normally supported in reversely inclined positions by seats on the shaft below and adjacent the points at which they are hinged, manual means for rotating and giving axial travel to the valve to open and close it, and deferred action operative connections between the valve and the bridge-breaker shaft timed to actuate the latter only after the valve has neared its fully open position.

11. Powder bin discharge structure according to claim 1 in which the valve has an axial stem having below its threaded portion an unthreaded portion at its lower end adjacent the valve, a tube enclosing the valve stem and preventing access of powder to the enclosed portion and a packed joint in the fixed structure through which the unthreaded portion is slidable.

12. A powder bin attachment comprising apowder receiving and discharging cup-shaped bin-mouth adapted for attachment to the bin adjacent its discharge outlet and in continuation thereof, a valve commanding said mouth and carried thereby, means operable from without the bin-mouth for opening and closing the valve, and shield structure carried by the valve, extending above and below the valve seat and spaced from and enclosing the bin-mouth, said spaced shield structure including an enclosing flexible shroud depending below the bin-mouth.

13. A cup shaped structure adapted for attachment to the taper end of the hopper of a powder bin in extension thereof and rotatably supporting an upstanding hollow bridge-breaker shaft coaxial with the cup shaped structure and adapted for insertioninto the hopper through its taper end, a valve commanding the powder discharge outlet from the cup structure having its stem within the bridge-breaker shaft and movably supported on said structure for axial opening and closing movement, and lost motion deferred action connections within said bridgebrealrer shaft between the valve and said shaft.

14. An attachment for a powder bin of the hopper bottom type comprising fixed structure adapted to be secured to the taper end of the hopper bottom in extension thereof, an elongated upstanding bridge-breaker shaft rotatably mounted on said fixed structure and having at intervals along the shaft transverse-bridgebreaker arms located in a common plane and having radial extension from the shaft greater at locations further up the shaft than near its bottom, but having less radial extension than length, being inclined to the shaft axis, the arms being arranged in pairs, arms at one side of the shaft being inclined downward and arms at the other side of the shaft being inclined upward, the maximum lateral extension of the bridge-breaker being greater than the corresponding dimension of the opening through the taper end of the hopper through which the bridge-breaker is introduced into the hopper, a valve commanding the discharge outlet from the hopper movably mounted on the attachment structure, and means for operating the valve and the bridgebreaker.

15. A powder bin discharge structure comprising in combination a powder bin having a hopper bottom narrowing downwardly to form a discharge end opening, fixed structure carried by the hopper bottom at its lower end, a valve mounted on said fixed structure for vertical movement and commanding the hopper discharge, a bridge-breaker shaft movably supported on the fixed structure and provided with a pair of fixed reversely inclined arms at opposite sides of the shaft, said pair of arms having a maximum lateral spread greater than the corresponding dimension of the discharge end opening of the hopper, but being introducible with the bridge-breaker shaft into the hopper through said discharge end, and means for operating the valve and the bridge-breaker.

16. Powder bin discharge structure comprising in combination a powder bin having a hopper bottom, a bridge-breaker mounted on fixed structure for movement within the hopper bottom, a valve commanding the outlet therefrom, means for opening and closing the valve, and means for subordinating the operation of the bridge-breaker to the operation of the valve, including deferred action operative connections between the means for opening and closing the valve and the bridgebreaker.

l'l. Powder bin discharge structure comprising in combination a powder bin having a hopper bottom narrowing to a discharge outlet, 2. bridgebreaker mounted on bin structure for rotation within the hopper, a valve mounted on bin structure for rotation, oscillation and vertical movement commanding the discharge outlet from the hopper and having handle means fast thereto, and deferred action operative connections between the valve and the bridge-breaker for operating the latter from the former and only in subordination thereto.

18. Powder bin discharge structure comprising in combination a powder bin having a hopper bottom, abridge-breaker carried by the bin on fixed structure at its bottom, extending within the bin and mounted for movement on said structure, a valve commanding the bin outlet and also carried by the bin and mounted on said fixed structure, means for opening and closing the valve, and operative connections between the said valve and said bridge-breaker, the only fixed interceptor projecting into the path of powder flow being located within reach of the attendant through the valve-controlled passage for the removal of foreign objects when the valve is open.

19. Powder discharge structure comprising in combination a powder bin having a hopper bottom, an upstanding bridge-breaker, a valve commanding the outlet of the hopper, means for operating the valve, and deferred action operative connections between the valve operating means and the bridge-breaker, the valve, the valve operating means, the deferred action operative connections and the bridge-breaker being all mounted as a unit on structure removably fixed to the hopper at its bottom, and the bridgebreaker being insertable as a part of said unit into the hopper through its discharge opening.

20. An attachment for a powder bin compris-

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