US2209257A

US2209257A - Fin-drum drier

Info

Publication number: US2209257A
Application number: US227001A
Authority: US
Inventors: Albert G Blank
Original assignee: Proctor and Schwartz Inc
Current assignee: Proctor and Schwartz Inc
Priority date: 1938-08-26
Filing date: 1938-08-26
Publication date: 1940-07-23
Anticipated expiration: 1957-07-23

Description

y 1940- A. .G. BLANK 2.209257 FIN-DRUM DRIER Filed Aug; 26, 1938 3 Sheets-Sheet. 1

Azza j 6% I BLANK FIN-DRUM DRIER Filed Aug. 26, 1938 3 Sheets-Sheet 2 yjie il 5y;

Patented July 23, 1940 UNITED STATES FIN-DRUM DRIER Albert G. Blank, Philadelphia, Pa., assig'nor to Proctor & Schwartz, Incorporated, Philadel phia, Pa., a corporation of Pennsylvania Application August 26, 1938, Serial No. 227,001

16 Claims.

This invention relates to improvements in what is known in the art as a fin-drum drier. Driers of this type normally include a hollow drum or cylinder which is provided on its outer peripheral surface with a multiplicity of parallel, circumferentially extending ribs or fins. The ribs or fins are spaced apart laterally and form a corresponding series of circumferentially extending grooves in the outer surface of the drum, which receive the material to be dried.

'The material to be dried is applied to the drum in either a liquid, semi-plastic or plastic state. Moisture is-driven out of the material by heat applied to the drum, usually by steam admitted to the interior of the drum through one or both of the trunnions by which the drum is normally supported for rotation about its longitudinal axis.

The dried material is usually removed from the grooves in the face of the drum by sharply pointed needles or blades operating in the grooves between the circumferential ribs, with the needles or blades pressing against the walls or surfaces of the grooves and ribs and acting as scrapers for cleaning from said surfaces portions of the dried material which tend to adhere thereto.

The scrapers are usually supported en masse by a rigid common carrier which normally extends substantially parallel to the axis of the drum, in spaced relation to the peripheral surface of the drum.

Different kinds of 1 materials require diiferent drying temperatures. It is, therefore, necessary to heat the drum to the temperature required for the particular material being treated. As a result of the heating of the drum to various temperatures, and the subsequent cooling of the drum, the drum is susceptible to variations in its axial length, i. e., as the drum heats and cools expansion and contraction of the drum in the direction of its axial length occurs. Such expansion and contraction results in variations occurring in the lateral spacing of the ribs and grooves on or in the peripheral face of the drum.

The scrapers operating in the grooves are usually more or less rigidly connected to the common carrier and, prior to the present invention,

the common carrier has been of a more or less rigid construction and was not afiected in any material way by variations in the temperature of the drum adjacent which the carrier was mounted.

With the scrapers rigidly connected to the rigid carrier and operating in the grooves of the drum, which as .noted above were susceptible to variations in their lateral spacing, the scrapers did not operate efficiently, because, as the drum expanded and contracted causing the lateral. spacing of the ribs and grooves to vary, the

scrapers were thrown out of alignment with the grooves which caused the operating ends of the scrapers to be flexed laterally, more or less, as a result of the scrapers each being rigidly connected to the rigid carrier and held firmly thereby'at one end while the opposite operating end.

of each scraper was confined in a groove formed between adjacent ribs of the drum and by which the operating end of the scraper was moved laterally'with respect to the fixed end of the scraper in accordance with variations in the length of the drum.

The object of the present invention is to mount the scrapers in such a manner that the lateral spacing of the scrapers can be varied in accordance with the variations occurring in the spacing of the ribs and grooves, to compensate for such variations and thereby provide more efficient contacting of the scrapers with the walls ofv the grooves and ribs.

The object of the present invention may be attained by any oneof a number of different methods embodying various forms of mechanism, the simplest and preferred form of which will be fully disclosed hereinafter, reference being had to the accompanying drawings, of which Fig. l is a diagrammatic plan view illustrating a drum of the fin or groove faced type with a scraper carrier mounted adjacent thereto, in accordance with the principles of the present in vention;

Fig. 2 is an enlarged transverse sectional elevation, illustrating a portion of the drum and the carrier, taken on the line 2--2, Fig. 1; and

Fig. 3 is a face view of those portions of the drum and carrier shown in Fig. 2 and illustrating the scrapers operating in the grooves of the drum between the adjacent ribs thereof.

In order that a more thorough understanding may be had of the type of apparatus to which the present invention more particularly relates, reference is made to the common assignees prior patent to Alpheus O. Hurxthal, No. 2,068,181, dated January 19, 1937. As shown in said patent, and as shown diagrammatically in Fig. 1 of the accompanying drawings, the drum l is of a hollow cylindrical shell construction. The drum or cylinder I is provided at its opposite ends with supporting trunnions 2 and 3 respectively. The trunnions 2 and 3 are rotatably mounted in vOperatingin each of the grooves 8 is a scraper needle or blade 9.] For most efiicient operation,

the scrapers 9 should engage substantially the entire area of the surface of the walls of the grooves.

Prior to the present invention, as shown in the above mentioned patent, jthejscrapers were rig-' idly secured to a common carrier which extended, parallel to the axis of the drum. As noted above, when the temperature 'of-the. drum varied,

the drum expanded or contracted axially. The

carrier for the scrapers, however, remained in a rigid fixed'condition. Consequently, the scrapers .were' thrown out of alignment with the grooves causing the operatingends of thescrapers to be' .fiexed from contactwith the entire surface of the grooves. Y 1 r In the presentcase the scrapers 9 are mounted on a hollow carrier III. The carrier 1 is provided withports II andxI2 at one or both ends of said carrier and which communicate with the hollow interior I3 of the carrier I0. I The ports and ,I2 areconnected, by pipes Ilaand I2a'res'pec- '40 the carrier I9 efiects variation in the lateral spacing of the scrapersQ, to compensate for the .ti-vely, to a suitable source of temperature controlling medium, such as steam for examplaby which the temperature of the carrier I0 maybe raised or lowered in accordance with variations in the temperature of the drum I and whereby the carrier III is ca'usedto expand or contract longitudinally in accordancm-zwith the axial expansion and contraction of the drum I.

The longitudinaliexpansion and contraction of variations in the spacing of the ribs .1 and grooves 8'which occurs as a result of the axial expansion and contraction of the drum I, wherebythe blades 9 are caused to maintain a more efiicient, constant and uniform contact with the base'and side wall surfaces of the grooves and ribs'for more thoroughly removing dried material from said 'walls which has adhered thereto.

It is preferable to control the direction in which the expansion and contraction of both the drum and the carrier occur with respect to some definite point or plane in both the drum and the carrier. Preferably, the drum and carrier are anchored against axial or longitudinal movement at points located in' a common plane extending transversely to each. -While such an anchorage point may be located anywhere between the opposite ends of the drum and carrier to permit expansion and contraction in opposite directions at both sides of and with respect to the common anchorage plane it is more convenient to have the anchorage located at one end of the drum and carrienwhereby all the expansion and contraction will take place at one side of the anchorage solely. In order to provide theabove -noted anchorages the drum I is provided with an annular shoulder I which makes firm contact with one end It of the bearing 4, to prevent relative movement in one direction between the drum and the bearing 4. Movement of the drum in the opposite direction with respect to the bearing 4 is prevented 'bya collar I'I secured to the trunnion comes appreciable.

2, as by one or more set screws I8, and having one surface I9 of the collar engaging the second end 20 of the bearing 4. Thus, with the one end 2| of the drum anchored against axial movement, the expansion and'contraction of the drum will occur at one side of the bearing 4 and with respect to the anchorage plane indicated by the line x.-x in Fig. 1.

In order to permit the above-noted axial expansion and contraction in the drum, the trunnion 3 located at the second end of the drum I or rigidly secured to the one end 21 Ofxthe carrier ID. The flange or fitting 25 is rigidly secured'to' the portion or side of the frame work 6 of the machine to which the bearing 4 forthe drum I is likewise rigidly secured. Thecarrier Ill, in the present instance, for the purpose of illustration, is shown as being secured to? the.

frame work 6 by suitable bolts '26, 26.

The opposite end of. the carrier IILlike th second end'of the drum I, is mounted inithe frame 6 in such a .manner as to permit free carrier II]. As a matter of illustration, the second end of the carrier I0 is slidably mounted in a free bearing 39 formed in or on or secured as by cap screws 3| to that portion of theframe 6 to which the free bearing 5 for the drum I is'secured.

From the above itwill be clear that, as the axial length of the drum I increases or decreases in accordance with a rise or fall in the temperature of said drum, it is possible, by controlling the temperature of the carrier I0, to cause said carrier to expand or contract longitudinally, sufficiently to compensate for the variations in the axial length of the drum I. Suchexpansion and contraction of the carrier ID will produce variations in the later'alspacing of the scrapers 9 which will correspond substantially to the variations occurring in the lateral spacing of'the ribs I and grooves 8 in the peripheral 'face of the-drum I.

Obviously, the variations in the spacing between any two. or betweenany relatively small number of the ribs 1 and grooves 8 is extremely slight and normally would produce no perceptible difference in the functioning of any'correspond ing two or relatively small number of adjacently disposed scrapers 9. However, when it is considered that there is a relatively large number of ribs and grooves in the drum and a correspondingly largenumber of scrapers on the carrier, the difference in the distance between the first rib at one end of the drum and the last rib at the opposite end of the drum when the drum is cool and between said first and last ribs when the drum is heated-to the maximum extent be- When the scrapers operating in the grooves are rigidly secured to arigid non-variable carrier this difference distributed along the length of the drum is sufiicient to throw the scrapers out of line with the respective grooves and cause inefficient operation of the scrapers. However, when the carrier I0 is of the expansibleand contractable type disclosed'herein .20 ing a flange or fitting integrally formed-with longitudinal expansion and contraction ofthe. Y

no such misalignment of scrapers and grooves is presented. l

In view of the fact that variation within any small group of ribs and grooves is rather insignifican't it is practical tolproduce the scrapers 9 in the form of relatively short comb sections, one of which is shown in Fig. 3. A number of scrapers 9 are grouped together by being cut from a single plate 32, by making a series of kerfs 33 inwardly from one edge of said plate and leaving a solid back bar 34 along the opposite'edge of said plate. A number of these comb sections are mounted on the carrier 10in end to end relation to each other.

The back bar 34 of each of the above mentioned combs is secured to a swinging frame 35 by

bolts

38, 35. Each swing frame 35 is provided with ears '31, 31 which are disposed at opposite ends respectively of a bracket 33. Each bracket 38 is secured to the carrier ID by means of cap screws 38. A pivot rod 40 extends through and beyond each bracket 38 into the ears 31, 31 of the associated swing frame 35, with its axis substantially parallel to the longitudinal axis of the drum I and the carrier l0. Axial movement of the pivot rod 40 with respect to the bracket 38 and ears 3? is prevented by a set screw4l threaded into the bracket and having bearing against said pivot rod.

Adjustment of the scrapers 9' in a direction transversely of the drum l and carrier HI, and whereby the proper pressure of the ends of the scrapers against the surface of the drum may be accurately controlled, is elfected by means of nuts 42 and 43 threaded onto adjusting rods 44 which are rigidly secured in the swing frames 35 and project therefrom through slots 45 formed in extensions 46 of the brackets 38, thrust blocks 4'! and 48 being provided on said adjusting'rods '44 between the nuts 42 and 43 and the bracket extensions 46. I

The slight variations indistances between small groups of the ribs 1 and grooves 8 are, compensated for by expansion and contraction of the back bar 34 of each of the scraper comb sections, said back bar being heated by conduction from the carrier 1 0 through the brackets 38 and swing frames 35 and from the drum l through the scrapers 9 themselves. Consequently, variations in the temperature of the drum 1 and carrier 10 are reflected in the back bars 34 of the scraper comb sections, causing the back bars of said comb sections to expand and contract longitudinally together with the drum 1 and carrier H2 causing a minute variation in the lateral spacing of the individual scrapers 9, 9 on each back bar 34 and thereby compensating for the minute differ ences between the lateral spacing of a relatively small group of ribs 1 and grooves 8 and a correspondingly relatively small group of scrapers 9 which respectively occupy said grooves.

The heating of the carrier, It and the conse quent longitudinal expansion and contraction thereof efiects Variation in the lateral spacing between the groups of scrapers 9, 9, formed on the several back bars 34, 34 which are mounted in laterally spaced relation to each other along the carrier In.

In the present instance the drum 1 is heated to the desired temperature by steam admitted through the trunnion Z byrmeans of a steam pipe 49, circulation within the drum being provided by the return or exhaust pipe 59 in the manner illustrated in the previously mentioned patent to Hurxthal, No. 2,068,181, said pipe 50 also serving to evacuate condensation from the lower portion of the interior of the drum I. In a like manner, inthe present instance, condensation in the lower portion of the hollow carrier I0 is evacuated through the lower ports [2 in said carrier.

While the drum I and carrier In in the present instance have been described as being heated by means of steam admitted to the interiors of said elements, it is obvious that gas or electrical heating appliances may be utilized as asubstitute for the steam in either the drum or the carrier or in both without departing from the spirit of the present invention.

I claim: a 1

1. A device for use with a drum having later-' ally spaced circumferential ribs and grooves intermediate said ribs, wherein said drum is subject to axial expansion and contraction producing variations in the lateral spacing of said ribs and grooves, said device comprising laterally spaced surface scrapers respectively operating said grooves between adjacent'ribs, and thermo sensitive means for varying the lateral spacing of said scrapers to compensate for said variations occur-ring in the lateral spacing of said ribs and grooves.

2. A device for use with a drum having later ally spaced circumferential ribs and grooves intermediate said ribs, wherein said drum is subject to axial expansion and contraction producing variations in the lateral spacing of said ribs and grooves with means disposed at a predetermined point along the length of said drum for preventing axial movement of the drum at said point and causing said expansion and contraction of the drum to be effected relative to said point, said device comprising laterally spaced surface scrapers respectively operating in said grooves between adjacent ribs, and thermo-sensitive means and grooves with means disposed adjacent one end of said drum for preventingaxial movement of said end of said drum and causing said expansion and contraction to be effected relative to said end, said device comprising laterally spaced surface scrapers respectively operating in said grooves between adjacent ribs, and thermo-sensitive means similarly anchored for expansion and contraction with respect to said end of said drum for varying the lateral spacing of said scrapers to compensate for said variations occurring in the lateral spacing of said ribs and grooves.

4. A device for use with a drum having laterally spaced circumferential ribs and grooves intermediate said ribs, wherein said drum is subject to axial expansion and contraction producing variations in the lateral spacing of said ribs and grooves,. said device comprising laterally spaced surface scrapers respectively operating in said grooves between adjacent ribs, and a thermosensitive carrier for said scrapers extending substantially parallel to the axis of said drum for effecting longitudinal expansion and contraction of said carrier for varying the lateral spacing of said scrapers to compensate for said variations point and. causing said expansionand contracloo occurring in thelateral spacing of said ribs and grooves. V

55' A device for use. witha'dru'm having'laterallyspaced circumferential ribs and grooves intermediate said ribs, wherein said drum is subjectto axial expansion and contraction produc-.

ing variations in the lateral spacing of said' ribs and grooves with means disposed at. a predetermined point along the length of said drum for preventing axial movement ofthe drum at said tion of the. drum to be effected relative to said point, said device comprising laterally spaced surface scrapers respectively operating' in said grooves between adjacent ribs, a thermo-sensitive carrier for said scrapers extending substantially parallel to the axis of said drum, and means disposed ata predetermined point along the length of said carrier for anchoring said'carrier against longitudinal movement at said point, tempera- .ture variations occurring in said thermo-sensitive carrier efi'ecting longitudinal expansion and con-'- traction of said carrier relative to said anchorage for varying the lateral spacing of said scrapers to compensate for said variations occurring in the lateral spacing of said ribs and grooves.

6. A device for use with a'drum having laterallyspaced circumferential ribs and grooves intermediate said ribs,wherein saiddrum is subjectto axial expansion and contraction producing variations in the lateral spacing of said ribs and grooves, with means disposedadjacent one end -.of said drum for anchoring said end of said drum against axial movement and causing said expansion and contraction .to be effected relative to said end, said device comprising laterally spaced surface scrapers respectively operating in said-grooves between adjacent ribs, a thermo-- sensitivefcarrier for said scraper extending sub- 1 40 stantially parallel to the axis of said drum, means foranchoring the end of said carrier lying adjacent the anchored end of the drum against lonjgitudinal movement, temperature variations occurring in said thermo-sensitive carrier effecting longitudinal expansion {and contraction of said carrier for varying the lateral spacing of said scrapers to compensate for said variations occurring in the lateral spacing of said ribs and 5 grooves. j 50 '7. A device for use with a drumhaving laterally spaced circumferential. ribs and grooves intermediate'said ribs, whereinsaid drum is subject to axial expansion and contraction producing variations in the lateral spacing of said ribs and grooves, said device comprising laterally spaced surface scrapers respectively operating in, said grooves between adjacent ribs, a thermo-sensitive carrier for said scrapers extending substantially parallel to the axis of said drum, and means for rigidlyconnecting said scrapers in groupsto said carrier, temperature variations occurring in 'said thermo-sensitive carriereffecting longitugrooves: between adjacent ribs a thermo-sensitive carrier for said scraper extending substantially parallel to'the axis of said drum, and means-for heating said carrier to effect longitudinal expan sion and contraction thereof for varying the lateralvspacing of said scrapers to compensate for said variations occurring in the lateral spacing of said ribs and grooves. I j

I 9. Ade'vice for use with a drum having laterally spaced circumferential ribs and grooves intermediatesaid ribs; iwherein'said drum is subject to axial expansion and'co-ntraction producing variations in the lateral'spacing of said ribs and grooves, said device comprising laterally spaced surface scrapers respectively operating in said form'of an elongated hollow element adapted to support a plurality of scrapers in laterally spaced relation along said element,'and means for heating the interior of said element to effect longitudinal expansion and contraction thereof for varying the lateral spacing between the scrapers therealong. a

11. A scraper carrier for drum driers in the form of anelongated hollow elementadapted to support 'a plurality of scrapers in laterally spaced relation along said' element and ports communieating with the hollow interior of said element for admitting and exhausting'a suitable fluidic heating mediumto said interior for heating said element and thereby effecting longitudinal expansion and contraction thereof and a consequent variation in-the lateral spacing of the scrapers therealong. 12.-'A scraper'carrier for drum driers in the form' of an elongated hollowelement'adapted to support a plurality of scrapers in laterally spaced relationalong said element and ports'communieating with the hollow interior of said element adjacent the opposite 'ends respectively thereof fofad-mitting and exhausting a suitable fiuidic heating medium to said interior for heating said element and thereby effecting longitudinal expansion and contraction thereof'and a consequent variation in the lateral spacing of the scrapers therealong. 13.'A scraper carrier for drum driers in the form of an elongated hollow element adapted to support a plurality of scrapers in laterally spaced relation along said element,.means for securing said scrapers-to said element in groups, and means for heating theinterior of saidelement to effect longitudinal expansion and contraction thereof for varying the lateral spacing between the said groups of scrapers therealong.

14. A scraper carrier for drum driers in the form of an elongated hollow element adapted to support a plurality of scrapers in laterally spaced relation along said element, means for securing said scrapers to said element in groups comprising a series of back'bars to each of which a plurality of scrapers is attached, means for connecting said back bars to said element in laterally spaced relation to each other therealong, and means for heating the interior of said element to effect longitudinal expansion. and contraction thereof for varying the lateral spacing between the said groups of scrapers therealong.

15. A scraper carrier for drum driers in the form of an elongated hollow element adapted to support a plurality of scrapers in laterally spaced relation along said element, means for securing said scrapers to said element in groups comprising a series of back bars to each of which a plurality of said scrapers is attached, a series. of swing frames pivotally connected to said element in substantially aligned laterally spaced relation to each other for respectively supporting said back bars, and means for heating the interior of said element to effect longitudinal expansion and contraction thereof for varying the lateral spacing between the said groups of scrapers therealong. 16. A scraper carrier for drum driers in the form of an elongated hollow element adapted to support a plurality of scrapers in laterally spaced relation along said element, means for securing said scrapers to said element in groups comprising a series of back bars to each of which a plurality of said scrapers is attached, a series of swing frames pivotally connected to said element in substantially aligned laterally spaced relation to each other for respectively supporting said back bars, adjusting means for controlling the positions of said swing frames relative to the longitudinally bisecting plane of said element, and means for heating the interior of said element to efiect longitudinal expansion and contraction thereof for varying the lateral spacing between the said groups of scrapers therealong.

ALBERT G. BLANK.