US2801035A - Power-operated loading gate for centrifugal machines - Google Patents

Description

y 1957 J. HERTRICH 2,801,035

POWER-OPERATED LOADING GATE FOR CENTRIFUGAL MACHINES Filed Sept. 17, 1953 3 Sheets-Sheet l IN V EN TOR. JOSEPH HERTRIC/L Dscsassn, Br ELISE HERT RIC/1L EXECUTE/X J. HERTRICH July 30, 1957 POWER-OPERATED LOADING GATE FOR CENTRIFUGAL MACHINES Filed Sept. 17, 1953 3 Sheets-Sheet 2 Egw2- IN V EN TOR. JOSEPH HERVE/[IL Dscsaszo,BV 551/255 l/E'JPTP/L'Il, fxecqrklx c-QLMQ I I z ATTORNEYS.

illll United States Patent POWER-OPERATED LOADING GATE FOR. CENTRIFUGAL MACHINES Joseph Hertrich, deceased, late of Hamiiton, Ohio, by Elise Hertrich, executrix, Hamilton, @hio, assignor to The Western States Machine Company, Hamilton, Ohio, a corporation of Utah Application September 17, 1953, Serial No. 380,860

Claims. (Cl. 222-504) This invention relates to improvements in loading gates or spout discharge mechanisms, particularly for loading charges of sugar massecuite or magma into sugar centrifugals.

In the sugar manufacturing industry, the separation of.

sugar crystals from mixtures of sugar crystals and syrup is carried out by treating charges of the mixture in centrifugal machines of the filtering type. A supply tank, or centrifugal mixer, is usually provided adjacent to a group of centrifugal machines to hold acomparatively large quantity of the mixture, and loading spouts or chutes extend from the bottom of the supply tank to positions permitting charges of the mixture to be discharged from the spouts and loaded into the baskets of the respective centrifugals. Each loading spout is equipped with a loading gate for controlling the loading operations. In order to minimize the manual labor involved in operating the loading gates associated with the centrifugal machines grouped around a supply tank, such actuation is preferably performed automatically, for example, by pressure fluid operated devices.

Accordingly, an object of'the present invention is to provide a fluid pressure operated loading gate construction, for centrifugal mixer tanks and the like, which will operate more efliciently than known constructions and is particularly suitable for automatically controlled operation supervised from a remote control center.

Another object is to provide a loading gate construction of the described character wherein the gate body, through which the material flows from the related loading spout, has an improved facing at one end against which the gate slidably bears, with the facing being formed to minimize the frictional resistance to sliding movement of the gate and to provide a wiping action for avoiding scoring of the slidably contacting surfaces and for preventing the build-up of crystal and syrup deposits on such surfaces thereby to ensure proper sealing of the gate against the facing when the gate is in its closed position.

Another object is to provide a loading gate construction of the described character, wherein the initial portion of the gate movement from its closed position is automatically effected upon relaxation of the pressure fluid applied force urging the gate toward its closed position so that the pressure fluid applied force needed for opening the gate is minim zed and the gate opens, at least partially, in response to failure of the fluid pressure operated actuating means to afford a visual indication of such failure.

A further object of the invention is to provide means for urging the gate against the facing with a substantially constant yieldable force during movement of the gate toward and away from its closed position and a wedging action on the gate at the conclusion of its movement toward the closed position thereof for tightly seating the gate against the facing of the gate body, and wherein, upon release of the pressure fluid applied force urging the gate to its closed position, such wedging action results in a component of that force which acts parallel to the facing in the direction of movement of the gate toward its open position and has a magnitude greater than the frictional resistance to movement of the gate toward its open position so that the gate then automatically opens, at least partially, to assist in opening of the gate and toaflord a visual indication of the release of the pressure fluid applied force.

In accordance with the invention a loading gate construction is provided with a facing on the gate body having relatively narrow bearing strips thereon for sliding contact with the gate and formed of a hard, wear resistant material, with the bearing strips being inclined relative to the direction of travel of the gate between the open and closed positions of the latter so that the bearing strips produce a wiping action on the contacted surface of the gate to avoid scoring of the latter andthe build-up of accumulated crystal andsyrup deposits, and means urging the gate against the bearing strips with a yieldable force to ensure sealing of the gate against said strips during movement of the latter to and away from its closed position. Further, the movements of the gate between its open and closed positions are guided by contacting guide members on the gate and gate body having inclined or wedging portions engageable during the concluding portion of the movement of the gate toward its closed position to then clamp the gate against the facing of the gate body, with the wedging portions being inclined sufliciently relative to the path of movement of the gate so that the component of the above mentioned yieldable force acting parallel to that path of movement and in the direction tending to open the gate is greater than the frictional resistance to movement of the gate in said direction whereby the gate automatically opens, at least partially, upon release of the pressure fluid applied force used for closing the gate.

The foregoing and other objects, features and advantages of the invention and a suitable manner of practicing the same will be apparent from the following description of an illustrative embodiment of the invention, when con-- sidered in connection with the accompanying drawings, wherein:

Fig. 1 is a fragmentary side elevational view, partly in section, showing portions of a centrifugal mixer having a loading spout extending therefrom, portions of a centrifugal machine arranged to be loaded from the spout, and a gate construction embodying the present invention and associated with the loading spout;

Fig. 2 is a front elevational view of the gate construction shown in Fig. 1;

Fig. 3 is a front elevational View, on an enlarged scale, ofda facing included in the gate construction of Figs. 1 an 2;

Fig. 4 is a fragmentary sectional View taken along the line 4-4 of Fig. 2, but on an enlarged scale;

Fig. 5 is a fragmentary sectional view taken along the line 5-5 of Fig. 2, but on an enlarged scale; and

Fig. 6 is a fragmentary sectional view taken along the line 6-6 of Fig. 5.

Referring to the drawings in detail, and initially to Fig. 1 thereof, a gate construction embodying the present invention is there illustrated and generally identified by the reference numeral it The gate construction 10 is shown associated with a loading spout or chute 12 extending laterally and downwardly from the lower portion of a mixer tank 14 to a position overlying the curb or casing 16 and rotatable basket 18 of a sugar centrifugal. The basket 18 is suspended in the usual manner-from a centrifugal spindle 20, which is adapted to be rotationally driven at high speed by suitable means (not shown) in order to separate syrup from each charge of sugar massecuite or magma in the basket and expel the and the lower endsof the H being connected by a lower cross-member 28 underlying the lower, margin; offthe spout outlet which isdefined bythe openipg' 30 irr the gate body, The upper legs '32 of the forward end wallor facingproject-abovethegate body and provide a slideway for a gate 34in movement of the latter away from and to clo'sed position across spout'outlet opening 30; a

7 As seen in Fig. 3, the forward end wall 'or facing;.24 has narrow bearing strips 36 and 3 8 thereon and against which the smooth rear face 'of closure or;gate; 34 is slidably engaged. Bearing strips 36 and 38 are formed of hard, we ar resista'nt metals which are welded tojhe, forwardface of end wall 2 4. For example, bearing strip 38, which extends around the opening 30, ispreferably formed'of a weld of high speed cutting tool metal, such as, Stellitewhichis an alloyiof steel with cobalt, chromium'jandtung sten, while bearing strips 36, extending upwardly from the lower corners of strip 38, are preferably forrned of stainless steel weld. It will be noted that the upper portions 36a of bearing strips 36 and the side portions 38a of bearing strip 38 are angled or inclined relative to the direction of movement of gate 34 away from and to its closed position, as indicated bythe arrow 40 (Fig. 3). Thus, while the bearing strips are narrow to minimize the area of the gate contacted at any time byfsuch strips and hence the frictional resistane mmevemem of the gate, the angled or inclined. character of portions 36a'and 38a of the bearing strips provides a wiping action across the rear face of gate.

34 auringmovemerit of the latter and transfers the area of contact laterally across the rear face to prevent scoring of the 'latteralonglines extending 'parallelfto the direction'of movement of the gate. The above mentioned wiping action further serves to remove accumulated crystal and syrup deposits from the rear face of' gate 34 wh'i'chfif left on the gate, might interferewith smooth seating of thegate against bearing strip 38 in its closed position across opening 30 and thereby cause leaking of the mixture past the imperfectly seated gate. The removal of accumulated deposits by the wipingtaction also prevents such deposits from interferingwith, or resisting,tmovement of the gate toward and away from its closed'position. v

Sliding movement of the gate 34 on the bearing strips 36 .and '38 away from and back to its closed position is effected by gate actuating mechanism including a cross 'head 42 which extends transversely across the outer or front side of the gate and has rearwardly turned or directed end portions 44 (Fig. 5) embracing the opposite side edge of'end wall '24 of the gate body. The 'rear edges of end portions 44 are inwardly flanged, as at 46, behind endwall 24, and guide members 48 and 50 (Figs. 5 and'6) are interposed between each of the flanges 46 and the rear face of the related side edge portion of end wall 24. The top and bottom ends of guide member 48 are formed with lips or rims 52 overlying and underlying, respectively, the-upper and lower edges of the adjacent end portion 44 and flange 46 at the related end of cross-head 42 so that each guide member 48 is constrained to move vertically with the cross head relative to gate body 22 and'the adjacent guide'member 50 which is secured to'end wall 24 of the gate body, as by machine screws 54. r

Each guide member 48; is formed with a forwardly end, to a fitting 9ti provided on theend of a pistonrrod extending from a piston (not shown) within a related clined rear surface which is parallelto the inclined front surface of wedge shaped extension'48a. The inclined surfaces of extensions: 48a and 50a (Fig. 6) are shown to incline forwardly in the upward direction so that, when such inclined surfaces slidably engage each other as a result of downward movement of cross-head 42,- the latter is urged rearwardly toward gate 34 for increasing the pressure of the latter against the bearing strips on end Wall 24; Further, extensions 50a are vertically disposed to engage. extensions 48a whenthecross head, and with it the gate 34, move through the con eluding portion of their downward movement eifective to cover the spout outlet opening 30.

In order to cause gate 34 to move vertically with cross head 42, bolts 56 extend through suitable pads at the opposite ends of the cross head (Fig. 2) and are loosely received in vertically elongated recesses 58 (Elgllti) formed in the front facezor gate e4, inns, the cross head 42 is free tomove through alirnited distance in-' dependently of gate 34 before bolts .56 irnpactl against' the walls of the corresponding" recesses 58, and such impact is helpful in achieving initialmovernent of the gate toward or away from its closed position; a

In order to'adjust the pressure of gate 34 against bear i ing strips 36 and 38 on end wall 24, pressureexerting 'shoes 60 are received in suitable vertical grooves in t-he rear surface of cross head 42 adjacent the opposite ends of the latter. Lugs 62, at the top and bottom ends of each shoe 60, embrace the upper and loweredges of the cross head (Fig.4) to constrain the related shoe to move vertically with the cross 'head. The cross head carries adjustable devices, generally identified by the numeral 64, for exerting variable, rearwardly directed pressures against the related shoes 60 for transmission, by "the latter, tothev gate 34. v Each'of the pressureexertingde vices 64 preferably includes a tubular member or sleeve 66 threaded into a suitable tapped bore in the: cross. head and accommodating a compression spring 68 bearing rearwardly against the related shoe 60. Each of'the sleeves 66, at its forward end defines a tool receiving socket 70 for facilitating screwing of the sleeve, more or less, into the cross head to vary the compressive force. of the related spn'ng.

Vertical'movement of 'cross head 42 is achieved by structure which includes links 72.pivotal.ly mounted, at

their lower ends, on stub shafts 74 extending laterally from the opposite ends of the cross head. The upper ends of links 72 are pivotallyv connected, as at 76, to the free ends of related bifurcated arms 78-Whi'ch extend radially from, and are fixed to, arock shaft 80 journalled in suitable bearingEbrackets'82formed on the top of gate body 22; Thus, angular displacement or oscillation of rock-shaft 80 is translated by the arms 78 and links 72 into vertical displacement of cross head 42.7 At one end, shaft 80 is provided with a handle: 84 for use in rockingthat shaft in an emergency. However, during normal operation, rocking of shaft'80 to displace the cross head 7 and, with it, gate 34 toward and awaylfrom'the closed position of the latter is effected by pressure fluid, preferably hydraulic, operated means. 1

Such pressure fluid operated means preferably includes actuating arms 88 fixed to shaft 80 adjacent the opposite ends of the latter and each connected pivotally, at its free cylinder 92. Each cylinder 92 is -rockably mounted at oneend ona suitable fixed .supportbracket, for example,

otherof the ends of the cylinder from a suitable source able surfaces of wedge- shaped extensions 48a and 50a are inclined sufficiently relative to the front face of end wall 24 so that the component Fa (Fig. 6), parallel to that front face, of the force P, which is the normal reaction of the wedge-shaped extension 50a to the force F exerted by wedge-shaped extension 48a in response to the action of springs 68, is greater than the frictional resistance to movement of gate 34 away from its fully closed position.

The above described device operates in the following manner:

In closing the illustrated gate construction, pressure fluid is supplied to cylinders 92 in the direction producing a pull on fittings 90 to effect counter-clockwise rocking of shaft 80, as viewed in Fig. 1. Such rocking lowers cross-head 42, and with it the gate 34, while springs 68 urge the gate against bearing strips 36 and 38. When the cross head and gate have been lowered to the position in which the wedge-shaped extensions 48a moving with the cross head engage the relatively fixed wedge shaped extensions 50a, further downward movement of the cross head, by the continued action of the cylinders 92, causes movement of the cross head laterally toward gate 34 to further compress springs 68 until the inner surface of the cross head directly contacts shoes 60 and urges the latter against the gate with a force greater than that normally exerted by the spring 68. Thus, a relatively great force acts against gate 34 in its closed position to urge the gate against bearing strips 36 and 38 and thereby to provide an effective seal about the spout outlet opening 30.

When the supply of pressure fluid to cylinders 92, in the direction causing closing of gate 34, is interrupted, either intentionally or as a result of a failure in the pressure fluid supplying system, the force acting downwardly on the cross head is removed, yet the springs 68 still act to produce the force F (Fig. 6) and the upward component Fa of the reaction F to that force is suflicient to overcome the frictional resistance to movement of the gate away from its fully closed position and to cause initial upward movement of the gate to the point where the gate is loose and sufiiciently open to allow a limited flow of material through the gate opening 30. In the event of a failure of the pressure fluid supplying system, this automatic opening movement will give a visual indication of the failure so that a person supervising the centrifugal operation from a remote control station may notice the failure and immmediately take steps for its correction.

The above described steeply sloped relation of the surfaces of extensions 48a and 50a also facilitates the opening of the gate by the normal action of the fluid pressure cylinders 92 in the event of sugar material crystallizing so as to freeze the gate in closed position. Further, its desired visual indicating function is promoted through the conjoint provision of the thin bearing strips 36 and 38 on end wall 24, for these strips, by limiting the frictional resistance to movement of gate 34, make it feasible to produce through the inclination of the extensions 48a and 50a a force component or reaction fully suflicient to overcome the inertia of the closed gate including such frictional resistance to its movement. present invention, the gates associated with a plurality of loading spouts may be safely and efliciently controlled or operated from a remote control center from which the gates are visible, and the visible discharge of material under a supposedly closed gate provides an indication vof improper functioning in the pressure fluid operated control system associated with that gate.

Although the illustrated embodiment of the invention is a loading gate adapted especially for a mixer or loading By virtue of the spout of the so-called refinery type, it will be apparent thatthe invention may be embodied in other forms and designs of apparatus without restriction to either the details or the specific arrangements of the illustrated embodiment. In the case of a tank and spout of the socalled plantation type, the gate body and actuating mechanism may be mounted so that the cross head and gate move me substantially horizontal plane, to allow material to flow almost vertically downward from the tank and spout. It is therefore desired that the invention be accorded a scope fully commensurate with its novel contributions to the art, as intended to be set forth in the appended claims.

What is claimed is:

l. A loading gate assembly comprising a hollow body adapted to form an end portion of a loading spout, said body forming a spout outlet and a face at the end of said outlet, said end face surrounding said outlet and having a portion extending to one side thereof, said end face being formed with narrow bearing strips of a hard wearresistant metal elevated from its surface and extending around said outlet and along said side portion, a gate fitted to slide on said bearing strips from a fully closed position covering said outlet to an open position in which it is displaced to said side thereof, yieldable means for pressing said gate against said end face, means connected with said gate for moving said gate along said bearing strips between said positions, power operated means operative to apply a powerful force through said gate moving means in the directions of the gate movements, means including inclined surfaces engaged by said gate moving means during a terminal part of the path of closing movement of said gate, whereby said gate moving means when moved by said force in said terminal part of said path, clamp said gate against said bearing strips under an extreme localized pressure to prevent leakage between said facing and said gate.

2. A loading gate assembly according to claim 1; wherein portions of said bearing strips are angled relative to the path of travel of the gate to wipe the contacted surface of the latter and distribute the wear over said surface.

3. A loading gate assembly comprising a hollow, open ended gate body adapted to form an end portion of a loading spout and having an end wall with an opening therein to define a spout outlet, said end wall having parallel, opposite longitudinal edges and an end face surrounding said spout outlet with a portion extending to a side of the latter; raised, narrow bearing strips of hard, wear resistant metal on said face of said end wall and extending around said outlet and along said side portion, a gate rectilinearly slidable on said bearing strips in a direction substantially parallel to said longitudinal edges between a fully closed position covering said outlet and an open position at said side of the outlet, a crosshead extending across said gate and loosely embracing said parallel longitudinal edges for movement therealong, said crosshead being connected to said gate and carrying yieldable means that constantly press said gate against said bearing strips, and actuating means for effecting rectilinear sliding movement of said gate and crosshead away from and to said fully closed and open positions of the gate.

4. A loading gate assembly according to claim 3; wherein parts of said bearing strips extending along said side portion are angled relative to the latter to wipe the contacted surface of said gate during sliding movement of the latter and distribute the wear over said contacted surface.

5. A loading gate assembly comprising a hollow body adapted to form an end portion of a loading spout, said body forming a spout outlet and a face at the end of said outlet, said end face surrounding said outlet and having a portion extending to one side thereof, said end face being formed with narrow bearing strips of a hard wearresistant metal elevated from its surface and extending around said outlet and .along said side portion, a gate ment of said gate; whereby said gate moving means when moved -by saidforce' in said terminal partrof said path, clamp said gate against said bearing stripsunderanex treme localized pressure to prevent l'e'ak'age betweensaid facing and said gate; the angle'ofsaidinclined surfaces and-thefo'rc'e ofsaid yieldable=-means when said gate sliding-meansareirrengagement with said' surfaces being such that they'pr oduee-a component ofthe last mentioned fOrceF-in-gate'openingdirection-suflieientinitself to move said gate sliding meansand thegateawayfrom' said fully closed-position in the eventof a-failnre of 'the power supply to said poweroperated means:

6. A loading gate-assembly comprisinga hollow body adapted to forrnan end portion'of a loading spout,said body forming aspout outlet and having'a face at the end of saidoutlet, said end face surrounding said outlet and havinga portion extending to one side thereof, a gate fitted to slideon said face from afully closed position coveringsaid-outlet to an open position in which it is displaced to said side thereof, yieldable means for pressing said gate against-said end face, means connected with the gate. for moving saidgate along'said endface between said positions, means inc1uding"incli-ned-- surfaces engaged by said lgate moving means during a" terminal part of the path of closing-,movement of said-gate for clamping said gate tightlyjagainst said end face;'the angle of said surfaces and the force of said yieldable means when said gatemoving means are-in engagement with said surfaces producing a component of said force in'gate opening direction suflicient in itself tomove said gate moving means andsaid gate away from said fully closed position, whereby. the gate will be automatically displaced to a partially opentpositionjn the absence of agate closing force appliedthrough said gate moving means.

7. A loading gate assembly comprising a hollow body adapted. to form-an end-portion of a' loading spout, said body forming a spout outlet'and'having a face at the endof said outlet, said end face surrounding said outlet and. having a portion extending to one side thereof, said endfacebeing formed with narrow bearing strips of a hardwear-resistant metal elevatedfrom its surface and extending around said outlet and along said side portion, a gate 'fittedto slide on saidbearing strips from a fullyv closed position covering said-outlet to an open position, in which ittis displaced to saidside thereof, yieldablemeans for pressing said gate against said bearing strips, meansv connected. with the gate formoving said gate. along said bearing stripsbctween said positions, meansincluding inclined surfaces engaged bysaid gate moving means during a terminal part of the path of closing movement of saidgate for clamping said gate tightly against said bearing strips, the angle of said surfaces and the force of said yieldable means whensaid' gate moving means are in engagement with said .surfaces producing a' component of said force in gate opening direction sufiicient in itself to move said gate moving means and said gate away from said fully closed 7 position, whereby the gate will be automatically displacedto a partially open positionin the absence of a gate closing force applied through said gate moving means. I

8.1Aloading-gate assembly comprising'a hollow body adapted .to. form an end portion of a lbading spout, said body: forming. a spout outlet and having a-face atthe end:.,of said .outlet,'said'end face surrounding saidoutlet and having --'aportion extending toone side thereof; a

gate fitted to'--slideon-- said facefr'om a fully closed posi tioncovering saidoutlet toanopen-position in wliiclr it is. displaced to said side thereofiayieldablemeans for; press ing said gate against said"endface;means-=including a" crosshead connected with the gate -for -rnoving said gatealong said-end face hetweerrsaid positions, parallel elon-f gated guides-fixed on---opposite sides oflsaid body behind; margins-of said end faceand extendingimthe direction ofumovement :ofsaid gate; saidicrossheadextending across" the. front of said gate and-havingbackwardly-andim wardly turned opposite end portionsformedtoengage andf slide along. said 'guide's 's'aid guides including-inclined surfaces engaged by said end portions duringQa' terminal part ofthepatl'r of closing movement'of 'said gate for displacingsaid crosshead toward-=said end' face=- to. clamp; said. gate thereagainsL-the-angle of 'said sur faces. and. the: forceaof said yieldable= means when said endportions are in. engagement with said-inclined surfaces producinga component of. said force-in" gate openingdirection. sufiicientin itself. to move said crossheadand said 'gateaway frornzsaidfullyw closed position, where by the gate willbeautomatieally.displaced to apartially open position'in theabsenceofa gate closingforceap- .plied through .said. gate. movingmeans;

9. A loading gate; assembly comprising a hollow gate body adapted to: formgan endzportiontof 'a loading spout, a facing mounted on,.and. surrounding the opening at, one

end of saidbody to definefla spoutoutlet, said facinghaving portions extended laterally away from said out--- let to onesideof saidbody, narrow bearingr strips, of relatively hard wear'resistant, material'fixed to; said fac ingwith partsof said s'tripsrsurrounding. said outlet and 1 other parts thereof extending away fromsaidsurrounding parts .and along said laterally extended facing portions at opposite sides of said'outlet;v said; strips having top surfaces elevated from said facing;and lying ina common flatplanega gate fitted to bear. and slide on saidstrip surfaces, means for pressing said gatetightly against" said surfaces, and meansfor sliding said gate on said having portions extended laterally away from said out-- let to one sideofsaid body, narrow bearing stripsof relatively hard wear resistant material fixed to said facing. with parts of said strips surroundingsaid outlet and other:

parts thereof extending away from said surrounding parts:

and along said laterally extended facing portions at op-' posite sides of. said outlet, said strips having top surfaces elevated fromsaid facing andlying in a commonzfiat' plane, a gate fitted to bear. and slide on said strip sur- 7 faces, means for pressing said gate tightly against said surfaces, and means for sliding said gate on said surfaces in the direction of said extended'portions between a closed position in which said gate closessaid outlet and.

; a position in which it is displaced to said one side there-.

of, both said surrounding parts and said other parts of said strips atopposite sides-of saidoutlet having top surfaces-extending at angles to said' direction to wipe and distribute Wear over contacted surfaces of said gate;

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