US2240989A - Degreasing of metal articles - Google Patents

Description

N. R. HOOD EI'AL 2,240,939.

DEGREASING OF METAL ARTICLES I May 6, 1941.

Filed Jan. 9, 1939' 3 Sheets-Sheet 1 1 oooooboooo m w n VOP 0 w s n ..R.B IA. .L

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May 6, 1941. N. R.'HOOD ET'AL- 2,240,939

DEGREASING 0F METALYARTICLES Filed Jan. 9, 1939 s Sheets-Sheet 2 NOrma n Rog Hood BY, Sarpue r'nes Spence!I ATTORNEY -N. R; 000 ETAL DEGREASING OF METAL ARTICLES May 6, 1941.

Filed Jan; 9, 1939 3 Sheets-Shegt 3 m rm. nH

.DR 2w m N U m N A M M s Y B 'wheels 3| in the direction indicated.

above the horizontal, rests on the edges of discs 38. To prevent the sheets sliding out while they are below the level of axle I fixed guides III concentric with the carrier are provided. Within the perforated axle 'l are two pipes II and HA, connected to a source of liquid solvent (not shown) and having a row of perforations along their length so disposed that jets of solvent can be projected radially to strike almost tangentially the sheets held in the rotating guides when they are disposed some 30-40 on either side of the vertical, one pipe projecting solvent on one surface of the plates and the other on the second surface. Conveniently solvent which thus enters the vapour compartment is allowed to collect in the lower part and can be drawn on through an overflow (not shown) leaving a depth of liquid sufficient to cover coils 28. The liquid drawn oif is diverted to a still distilling solvent at a high rate, and the distillate is returned to the jet pipes by a pump which forces a stream of solvent out through the jets. A duct 35 is also provided inside the axle I through which air can be sucked under a small pressure from the space between the plates when they are almost vertically above.

the solvent bath. A condensing coil 31 running along the inside of the axle to which cooling water can be supplied also facilitates the recovery of vapour from the spaces between the sheets in the guides above the axle.

The mechanism for supplying metal sheets and driving the carrier comprises a chain wheel I 6 connected to a source of power (not shown) which, through endless chain I8 drives chain wheel l9 and chain wheel 30, the former of which. through eccentric 20. link 2|, arm 22, pawl 23 and ratchet wheel 24 coaxial with carrier 6 and rigidly attached thereto, imparts an intermittent progressive rotary motion to the carrier in the direction of the arrow, while the latter (chain wheel 30) drives endless bands 5 around chain Through chain wheels and chains indicated generally at 3, end chain wheel 3| also rotates spider 2, while by means of ball bearings 4 sheets delivered by the spider 2 are held above moving bands 5 until a projection 32 thereon comes up against the edge of the sheet and carries it forward. In this way scratching of the metal sheet' throughv relative motion of sheet and bands is prevented. Ball bearings 8 and guides 9 are also provided to direct sheets leaving the band into the space between two guides in the rotating member. One sheet is thus shown in position. v

The mechanism for removing the sheet com-- I prises an endless chain l4 passing over pulleys 49 one of which is free, and the other of which is driven through gears 26, 21 and shaft 36 from the same source of power as wheel I 6. The chain is oriented vertically above axle I of the carrier 6,

extends well beyond the side of the degreasing compartment. and carries several pairs of spring clips I3 (in Figure 3 three pairs are shown) the clips of each pair being spaced apart along the chain by a distance less than-the width of the metal plates to be treated. The clips are of sucha length that as they are carried by the portion of the chain beneath the pulleys they are able to grip that part of the plate in the guide vertically above axle I which projects out of the carrier.

The clips are of course narrow enough to avoid fouling the plate in the adjacent guide.

To avoid complicating the drawing they have been omitted from Figure 2. Each clip I3 comprises an arm 39 fixed to a link of chain I4, and carries-on one side two ball races 42 and 43 at different levels, while on the other side is a fixed member H to which is pivoted a second arm 44 carrying above the pivot an outwardly projecting ball race 45. The lower ends of arms 39 and 44 are bent to form laws 46 normally held closed by the action of coil springs 41. Jaws 46 have forklike projections 48 pointing in the direction of progression of the clips, which act as guides to Each of the pair of clips is similar except that in the leading clip of each pair ball race 45 is at a higher level than the ball race 45 of the following clip, for the purpose which will be subsequently explained.

To operate the clips there are provided guides I5, l5A,and I5B. Guides I5B extend substantially the whole distance between the chain wheels 49 carrying chain at such a height and in such a position that while clips I3 are moving along beneath ch'ain I 4, ball races 42 and 43 hear one against each of them. Guides I5A are parallel to guides I 5B and comprise two members one above the other, the upper extending from beyond the carrier 6 on the side opposite to that at which the sheets are removed from carrier 6 to vertically above the forward portion of a sheet in the carrier and at the level of the ball race of leading clip I 3, while the lower guide I5A extends from the same side of carrier 6 to vertically above the rear portion of the sheet and is at the level of the ball race 45 of the following clips I3. Herein forward" means towards the side of the degreaser from which the sheets are removed.

The distance between guides I5A an'd I5B is such that chain I4 carries the clips between them, and that while ball races 42, 43 of each clip bear against guide I513 springs 41 of the leading clip l3 are compressed by the ball race 45 hearing against the upper guide I5A thus opening jaws 46, and springs 41 of the following clip I3 are compressed by the ball race 45 bearing against the lower guide I5A thus opening jaws 46 of that clip. The difference in length of upper and lower guides ISA corresponds to the distance apart of the following and leading clips I3, so that when ball race 45 of the former comes to the end of the lower guide, ball race 45 of the latter reaches the end of the upper guide. Further movement of chain l4 then carries the ball races past the guides thereby simultaneously .releasing each of springs 4'l' thus closing jaws 45 causing each clip to grip the sheet in the carrier at the same time, and. carry it out of the carrier to beyond the degreasing apparatus. Figure 3 shows one sheet 41 about tobe gripped by clips I3.

To release the sheet from the clipsa similar pair of guides I5 are provided beyond the degreasing compartment which coact with ball races 45 in a corresponding fashion to open simultaneously the jaws 46 of each spring clip, thereby releasing the sheet. Further movement of chain I4 will carry the clips'beyond guides I5 whereupon the jaws 46 will close and they will travel back along the upper side of the chain 'and down between guides I5B and I5A again thereby causing the jaws to open. They will then pick up another sheet and so on. To direct the clips between the guides and to enable pressure on ball races 42 to be applied gradually thereby facilitating smooth working the ends of the guides at which the clips enter may be bent outwards as shown inl igure- 2.

In the above apparatus the various movements, introduction and removal of the sheets to be the 310? position the last traces of vapour are removed by a slight suction createdin theduct 35., At the 310 position the plate is removed treated, rotation of the carrier and so'forth are all brought about by one prime mover, and the timing of each movement so that the whole operation proceeds smoothly is brought about" by appropriate choice of the length of band 5 elements 2|, 22 and the diameter of elements platesat but a small angle and each plate is" separated from its neighbour, no diificulties are experienced in securing adequate flushing, drainingand vapour treatment, and yet a large numby clips l3, carried beyond the side of the apparatus and released from the clips by the. action of guides I5, to be delivered to a chute or other receptacle.

Since the liquid solvent is jetted onto the --ber of plates can be treated simultaneously.

It, 20, 26, 21, etc. It can thus be arranged, that while arm 22 is moving towards the vertical (the .carrier being prevented from moving with it by pawl 25 being thus-at rest)'-'clips ii are in posltion to pick up a sheet between the two guides vertically above the axle and carry it beyond the side of the apparatus, and simultaneously the bands 5 deliver a sheet over bearings 8 into a slot in the rotating carrier. When these two operations are completed, arm 22 starts to move in the opposite direction, and,

arm 22 coacting with pawl 23, the carrier is rotated to bring the next guide carrying a degreased sheet into the vertical. position, while the next empty guide is .brought into position to receive a sheet. At the same time a sheet (indicated at I) is fed into spider 2 by hand ready to be placed on bearings l and conveyed along band! to be delivered into the carrier when it is next at rest, while clips 13 are made arm 22.

In using the apparatus sheets fed into the Moreover, even with such a small rate of movement of the carrier 6-e.g. 1 revolution in two minutes-that no disturbance of the vapour level is caused it is possible to treat as many as 1000- 1500 sheets per hour.

Many variations of the, invention are possible; for example,- more than two jetting pipes may be provided and it may be arranged that while tor the last jetting treatment pure solvent is used, earlier jetting is carried out with less pure solvent. Thus the lower part of the vapour zone may divided into two by a vertical partition in the plane of the axis of the' carrier and pure solvent supplied to pipe HA; this will collect in the right hand division of the vapour zone spider by hand travel along the band to be inserted into the carrier in the manner above indicated, and then pass into the degreasing zone. The further operation of the plant can be understood by following the treatment of one plate as it passes through, its position being indicated by the angle through which it has travelled after being inserted .into the carrier.

At 40, the cold sheet enters the-vapour zone, and solvent condenses thereon, to drain oil and be replaced by fresh condensate which in turn.

drains off. This treatment, of course, continues as the plate moves through the vapour zone until it attains the temperature of the vapour;

thereafter vapour will not be condensed, and any adherent solvent liquid will evaporate. At

. IO-80 one surface of the sheet is washed by jets angle between successive slots.

between the plane in which a plate leaves the apparatus andthe plane in which it enters it and may be pumped thence directly to pipe ll, tocollect in the left hand division whence it may be delivered to a still for purification and redelivcry to pipe HA.

In another variation of our invention the plates may be given two separate vapour treatments before removing them from the apparatus by providing the rotating carrier with an odd number of slots and arranging that each movemerit of the carrier rotates it through twice the If the .angle corresponds to an even multiple of the angle. between successive slots, a plate .on first emerging from the vapour will be carried past both the position where clips can coact with them and where a new plate would be'delivered into the same slot, so that it is immersed for a second time in the vapour. On emerging for the second time, however, it will be brought into position where clips l3 can remove it from the apparatus, and the empty slot will be brought into position to receive another plate. The cooling which the plate will receive while it is rotating above the vapour after its first immersion ensures that condensate will form on it during its second immersiom.

Further if it is not so. important to avoid scratching of the plates it'would be possible to dispense with the spider 2 and put in its place a hopper adapted to take a number of plates in a horizontal position the lowest of which will rest on the ball bearings 4. A stop would be arranged on the delivery side of the hopper so that only the lowest plate'would move when the projection" came round and forced this lowest plate on to the travelling band 5.

The apparatus can also be adapted for use with a liquid solvent in 'which case the depth of the liquid would be such as to reach to the axis, the air draught through the duct 35 would have to be increased so as to dry the plates which in "this case would be cold. If necessary a duct carrying heated air could be brought into the towards the axis; between the 270 position and 7 chamber near the top so that it will 'play on the plates. Ducts u and'l l-A might be omitted but a the'movement of liquid over the plates induced by the jets from II and HA would probably be found useful. The heating and cooling coils 28 and I! could also be omitted.

This invention is a valuable advance in the art as it gives a compact device eflicient in operation which will deal with a, large output andwork in a continuous and simple manner ,to deliver the plates both degreased 'and completely dry.

.As many apparently widely different embodijmen ts of this invention may be made without compartment and adapted to maintain at least rier after they have emerged from the solvent vapour.

aportion of the solvent in the vapour phase, a

cooling element situated above the heating element adapted to condense the solvent and thereby prevent the solvent vapour from rising,

above the level of the cooling element, a carrier adapted to rotate within the compartment and adapted to hold a plurality of metal sheets spaced apart from each other and held radially in the carrier which is so disposed within the compartment that as the carrier rotates the metal sheets are firstly completely immersed in the solvent vapour and then lifted completely above the solvent vapour, and spray means positioned at the axis of rotation of the carrier to create at least one distinct zone of relativelynarrow arc in which a stream of solvent. in the liquid phase can be passed over the sheets while said sheets are immersed in the solvent vapor.

2. An apparatus for the degreasing of metal sheets comprising a compartment adapted to contain a solvent for the grease, a carrier adapted to rotate withinthe compartment, and adapted to hold a pluralityof metal sheets spaced apart from each other and held radially in the carrier which is so disposed within the compartment that as the carrier rotates the metal sheets are flrstly completely immersed in the solvent and then lifted completely clear of the solvent, and means whereby at least one stream of solvent can be passed over the sheets from the axis of the carrier in a radial direction while the sheets are immersed in the solvent.

3. An apparatus for the degreasing of metal sheets comprising a compartment adapted to contain a solvent for the grease, a carrier adapted to rotate within the compartment, and adapted to hold a plurality of metal sheets spaced apart from each other and held radially 5. An apparatus as claimed in claim 2 in which means are provided to rotate the carrier with an intermittent motion, means being provided to place each metal sheet in position in the carrier at a time when the carrier is stationary; further means being provided for removing each sheet, after degreasing, from the carrier while the carrier is stationary. I

6. An apparatus for the degreasing of metal sheets comprising. a compartment adapted to contain a solvent for the grease, a carrier adapted to rotate within the compartment, and adapted to hold a plurality of metal sheets spaced apart from each other and held radially in the carrier which is so disposed within the compartment that as the carrier rotates the metal sheets are flrstly completely immersed in the solvent and then lifted completely clear of the solvent, and means to rotate the carrier with an intermittent motion, means being provided to place each metal sheet in position in the carrier at a time when the carrier is stationary; said means comprising a moving belt. and guides adapted to lead the plate into its correct position in the carrier above the level of the solvent; further means being provided for removing each sheet, after degreasing, from the carrier while the carrier is stationary, said means comprising clips carried on a travelling belt which clips are adapted to close on the sheet when the sheet is above the level of the solvent and carry it out of the compartment.

clips can'ied on a travelling belt which clips are adapted to close on the sheet when the sheet is above the level of the solvent and carry it out of the compartment.

8. An apparatus for the .degreasing of metal sheets comprising a compartment adapted to contain a volatile solvent for the grease, a heat,-

. ing element situated near thebottom of the comin the carrier which is so disposed within the compartment that as the carrier rotates the metal sheets are firstly completely immersed in the solvent and then lifted completely clear of the solvent, means whereby at least one stream of solvent can he passed over the sheets from the axis of the carrier in a radial direction while the sheets are immersed in the solvent, and means for passing a stream of air over the sheets and'towards the axis of the carrier after they have emerged from the solvent.

4. An apparatus asclaimed in claim 1 in which means are provided for passinga stream of air over the sheets and towards the axis of the carpartment and adapted to maintain at least a portion of the solvent in the vapour phase, a

cooling element situated above the heating element adapted to condense the solvent and thereby preventing the solvent vapour from rising above the level of the cooling element, a carrier adapted to rotate within the compartment round an axis approximately level with the surface of the solvent vapour and adapted to hold a plurality of metal sheets spaced apart from each other and held radially in the carrier in such a manner that as the carrier rotates the metal sheets are first completely immersed in the solvent vapour and then lifted completely above the solvent vapour, at least one duct situated within the axleof the carrier adapted to spray liquid and means driven from the same source of power as rotates the carrier comprising a. spider adapted to deliver the metal sheets one by one on to a moving band which is adapted to coach with guides and bearings to deliver the said metal sheets to the carrier when the carrier is stationary: further means also driven from the same source of power comprising a. travelling band, spring clips adapted to coact and be operated by guides in such a. manner as to grip a cleaned metal sheet in the carrier and carry it Outside the compartment at such a time as the carrier is stationary.

NORMAN ROY HOOD.

SAMUEL BARNES SPENCER.

CERTIFICATE OF CORRECTION. Patent No. 2,2l|.0,989. May 6, 191 1.

NORMAN ROY HOOD, ET AL.

It is hereby certified that error appears in the printed specifi of the above numbered patent requiring correction as follows: Page h, sec- 0nd column, line 5, claim 5, for the 'claim.reference numeral "2" read l-; and that the-said Letters Patent should be read with this correction therein that the same may conform to the 'recorc i of the case in the Patent Office,

Signed and sealed this 17th day of June, A. 'D. 19m.

cation' Henry Van Arsdale,

(Seal) Acting Commissioner of Patents.

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