US2194282A - Feeding mechanism - Google Patents

Description

March 19, 1940. F. JOHANNESEN El AL FEEDING MECHANISM Filed Dec. 22, 1933 MNNN QR aw INVENTORS Patented Mar. 19, 1940 UNITED STATES PATENT OFFlCE FEEDING MECHANISM Frank J ohannesen, Erie, Pa., and Frank Swenson, Teaneck, N. J., assignors to Linotype Parts Company, New York, N. Y., a partnership Application December 22, 1938, Serial No. 247,226

6 Claims. (01. 22-80) This invention relates to feeding mechanisms adapted for releasing. heavy Weights and. of which their movement is regulated by a substantially sensitive control. It especially relates to automatic feeding mechanisms adapted for releasing at intervals an ingot or pig touching the surface of a molten metal, whereby to maintain the surface of this metal at'a substantially constant height while definite quantities thereof 10 are withdrawnfrom the melting pot.

Automatic feeding mechanisms of this type are being. used in type casting machines and the .like; but while, in a general sense, such metal feeders are known to give a certain amount of satisfactory service, they nevertheless lack definite reliabilityand certain other necessary qualifications required bythe industry.

. It has been found that it is not alone essential to provide feeders which will give fairly satisfactory service, but it is also efipected that they are absolutely reliable in operation during any period; that their mechanism is rugged and simple in design; that they are fool-proof, and that their release mechanisms, employed for controlling the feed device of the ingot, be very sensitive,so that the withdrawal of even a comparatively insignificant quantity of metal from the pot, will result at once into a definite response for a. release of the ingot and causing it to move into the molten metal until its surface level has again reached its normal height.

. A distinct'advantage of such a sensitive and quick control is, that the capacity of the melting pot'can be reduced and made comparatively small, so that not alone less space will be required for 'the pot, but the quantity of fuel for heating the metal is decreased.

'Itis therefore one of the objects of the present invention, to provide a feeding mechanism 40 wherein the ingot release, which is actuated by a float swimming on the surface of the molten metal, is sumciently sensitive to positively respond to a change in weight of the float, and which change is of a degree ranging to within a small fraction of the actual weight of the It is another object of this invention, to provide a feeding mechanism with a pendulum escapement for actuating a stop member, whereby .50 to not alone make the operation of the mecha- 55 vide an efiective control-'brake device, and this of a type,'wherein the brake surfaces can be hardened without causing slippage. The life of the feeding mechanism, due to the absence of wear on these hardened surfaces, is thereby prolonged indefinitely. 5

the claims, are attained by the inventiondisclosed in the drawing, wherein:

Fig. l is a front elevational, partly diagram- 19 matic view of the metal feeder, shown applied in operative association with a melting pot.

Fig. 2 is an enlarged front elevation of the metal feeder, with its cover almost completely removed. Y 5

Fig. 3 illustrates a side elevation of the metal feeder, on line 3-3, Fig. 2.

.Fig. 4 shows a partial rear View of a ratchet drive, and Y a Fig. 5 a side viewof a control element. 20

Referring to the drawing, the automatic metal feeder l, is of a self-actuating type. It is independent of any moving parts of the type casting machine and is therefore not operatedby any pre-determined stroke of somelever on the ma- 25 chine. The release of the ingot 2 is solely depending on the height of level of the metal 3 l in the metal pot 4, thereby insuring an even flow of metal in direct proportion to the amount withdrawn. so

The ingot or pig 2, which is connected to the feeder l by means of a chain 5, has at its top an auxiliary weight. 6, which serves no other purpose but to supply sufficient weight for continuing the operation of the feeder mechanism 35 while the length and therefore the pulling force of the ingot has been reduced to almost nothing, or at least to a small fraction of its former size. When this occurs, the circular stop member. 1 at the other end of the chain 5 will have reached ,40 an obstruction on the feeder housing and thus prevent the auxiliary weight 6 from moving into the molten metal.

The iron float 8,v swimming on top of the metal surface, is suspended by a light-weight chain 9, which is fast to a transversely located pin Ill, adjustably held' in a threaded binding post ll, Fig. 2. The float 8 may thus be located in almost any position, depending on the location' of the melting pot and the shape of its opening. The operating mechanism of the metal feeder I is confined within a cast metal housing [5, ad-

' justably mounted to a stationary tube or rod I 4.

A cover I6 is held to the top surface of the housing by suitable screws 11.

The feeder chain 5 engages the sprocket wheel l8, which is fast to a ratchet wheel l9 freely rotatable on a shouldered stud or post 20, which is either driven or screwed into the bottom part of casing I 5. A spring operated pawl 2|, adapted to engage the teeth of the ratchet whee1l9,is movably held on adriving gear.22 by means of a shouldered screw 23. Gear 22 engages an intermediate pinion 24 which is fast to the hub 25 of an intermediate gear 26 freely rotatable with pinion 24 on a stationary pin 21 driven into the base of casing I5.

Intermediate gear 26 engages a driven .pinion 28, to which is securely heldp'an escapement or star wheel 29. The driven ,pinion with itsstar wheel is free to rotate on the shouldered stud or post 20. Suitable lugs 30 on the inner surface of cover I6 serve the purpose to position both'the gear 25 and the 'driven pinion 28 in an axial direction.

In order to positively maintain the stationary post 20in a rigid condition, a bearing plate 3! is provided, which snugly fits'onto the rounded inner surfaces of the casing wall 32 and which is held to "the casing by'fiat head screws 33.

The driving force exerted by the ingot on the sprocket wheel will tend to rotate the sprocket and'the star wheel in 'a counter-clockwise direction. W'hen'rotating, their speed will be retarded however by the presence of an escapement lever or pallet arm 34 of the pendulum type and of which its pallets 35, placed 180 degrees apart, interact with the teeth of the star wheel, thereby causing the arm 34 to oscillate.

The escapement lever '34, which ispreferably made of sheet metal, has'riveted to its upper end a T-shaped bearing block 36, adapted to receive a shouldered fulcrum screw 3'! which is held in the middle of the extreme upper section of housing [5. Underneath this screw an opening or clearance hole 38is 'providedin arm 34 for clearing'the circular hub 25. Below this opening, a still largerclearance hole 39 in arm is adapted to permit the'star wheel to rotate within the confines'of'the escapement' arm.

At the lower end part of this swinging arm is riveted a grooved pin-engaging block 40, adapted to operatively connect with a circular pin 4|, which is securely fastened to an oscillatable brake drum 42,'provided atboth of its faces with. trunnionsor pivot pins 43, 44.

Trunnion 43 is rotatably held in a mounting 'block'45, which is secured to casing I5'by a screw 46 and rigidly positioned by two steady pins on this block and entering the base of easing I5. A b1"; ge member 48, supporting trunnion 44, is held to the upper surface of the mounting block by means of screws'49. The bridge members feet (not shown) are provided with suitable steady pins adapted to enter'the holes 50 adjacent the screws 49.

In order to control the number of strokes or oscillations required for the release of a definite quantity'of pig metal, a sensitive control device is provided and which comprises a hardened brake lever-52, adapted to engage the hardened cylindrical surface of the brake drum 42. The brake leveris fulcrumedon apivot pin 53, fast in the mounting block 45 and has at its other extremity an adjustable screw and nut 54, which are adapted to regulate the height of a hardened contact pin55, .of which its lower surface engagesa hardened lever surface 56 of a cylinder 51' rotatably held at both its end portions in the mounting block 45 and the recessed housing section 15 respectively.

The cylindrical force lever 51 is provided with a rod 58, extending from the right side to the 5 left and to the outside of the casing, where it engages an indent 59 in a movable beam or control bar 60. The latter is held vertical and is guided by:shoulder screws 6|, 62, engaging slots 63 of said bar. The thread of the upper screw 10 5| engages the wall of casing 15, while the lower screw 52 is held in the lower end portion of mounting "block 45 protruding from the casing.

The weight of the vertically movable bar 80 is overcome by a flat spring 65, secured to the 15 lower surface of block 45 by suitable screws 86 .and which is adapted to engage at its free end a slot'BT, cut transversally on the inner, wide surface of bar 60.

The lower end part of this bar is bent at right angleand is 'adapted'to'maintain the threaded post which, with its float supporting pin I0, may be rotated into any suitable position and thereafter *locked by means of a nut 68. The narrow front surface of bar 60 is flush with the upper surface of the mounting block 45, which again is substantially flush with the finished upper surface of easing IS.

The function of the flat spring 85 is, to not alone lift'the vertical bar GDwith the attached a light-weight chain"9,'but to also press the hardened brake lever 52 against the brake drum 42 by means of the force lever 5'1, 58 engaging bar 60.

Forthe reason that the star wheel 29 has been speeded up by a gear ratio of approximately 6:1; that the blowsof this'wheel are received by the angular faced pallets of the pendulum, and that furthermore an increased leverage in this pendulum actuates the brake drum 42,it is evident, thatthe force still residing in this drum will be comparativelyismall.

To arrest the movement of the oscillating drum by the small forced the flat'spring 85, the pivot pin 53 of the brake lever 52 has been locatedina most favorable manner relative to "the adjustable contact pin 55 at its other end,

so that'the force required on'the brake lever is reduced bymorethan'three times the amount needed .forstopping the drum. This leverage has been further augmented by a greatly magnified lever ratio, obtained by the construction of the very short force lever 57' and its lengthy extension '58, engaging the vertical beam 60. The active'movement of the brakev lever 52 to and from the brake drum may thus be made extremely short, requiring less than ,6 of an inch travel.

It is therefore quite evident-that the spring power required'for arresting the oscillating movement of the brake drum is very small, and that in consequence thereof, the least amount of variation on the surface of the molten metal and therefore on the weight of the float 8, will at once causea definite and very reliable reaction on the feeding mechanism.

It has been found by actual tests, that the force required to either release or to arrest the movement of the approximately twenty-five pound weight of the ingot 2, by means of the lever 58, is not more than three ounces. Even though both the contact surfaces of the brake drum 42 and the brake lever-52 are hardened and polished, a three ounce force, coming from either the float chain 5 or the reacting spring'65, will therefore definitely'operatethefeeding mechanism without causing slippage. That the sensitiveness of the instance, have to melt a larger quantity of cold ingot metal than in the other. Should the operator cast large slugs, leads or rules, it is evident, that if the ingot does not feed almost continuously, but during long intervals only, its metal can not melt fast enough to keep up with the metal withdrawn. The result is, that the feeding mechanism keeps dropping cold metal into the pot, which may result into a so-called "low pot, and of which the effect would be hollow instead of full castings or slugs.

The pig may ultimately rest on the bottom of the pot and under extreme conditions, may

even unhook from the feeder chain. Should the operator leave the machine and not notice that all of the cold ingot metal had not been melted, the gradually dissolving metal could create an overflow of metal from the pot, which might damage electrical and other parts of the machine.

Even though the operator should be careful in overcoming the above mentioned possible defects, he would, nevertheless, be forced to slow up production, on account of the ingot metal melting slower when not fed in short and progressively continuous steps during high speed type casting operations.

Raising the degree of sensitiveness of the floatoperated release mechanism, will therefore produce the novel result of eliminating possible defects which might occur during type casting operations, and by furthermore increasing the eficiency. The latter would be characterized by a higher speed in production and a consequent reduction in cost of operation.

The invention described, comprises therefore a novel self-actuating type of metal feeder which is independent of any Dre-determined actions or strokes of an outside machine and which feeder reacts to the slightest depletion of metal from the melting pot. Its locking action is positive, permitting no slippage. This in turn permits the introduction of hardened surfaces at places where wear might occur, extending thereby the life of the mechanism by a considerable degree.

Due to the sensitiveness of the releasing action, this feeder can therefore be applied for 'melting off the very last piece of metal of the ingot or pig, if so desired. In order to place a new ingot onto the chain 5, the operator will simply pull down the chain disk 1. This will make the ratchet device operate until the ingot carrying weight 6 has been raised to the height desired.

Having described the invention, it is evident, that various modifications thereof may be apparent to those skilled in the art, without departing from the spirit and scope of the invention, and it is therefore understood that the same is only to be limited by the scope of the prior art and the appended claims.

What we claim is:

1. A feeding device of the type adapted to feed metal ingots to a melting pot,comprising a casing, an element carrying an ingot to be fed to the pot and driven by the weight of said ingot, gearing driven by said element, supports for said gearing, a star wheel driven by said gearing, and

an escapement lever driven and oscillated by said star wheel, said supports being sustained in said casing and located to penetrate the plane of operation of said lever, the form of said lever being adapted to permit said supports to extend from the rear to beyond the front surface of said lever, whereby to substantially decrease the magnitude of space required for said feeding device, a brake element oscillatably driven by said escapement lever and having a friction surface, and a friction lock lever adapted to engage said friction surface, whereby to stop the movement of said ingot.

2. A feeding device of the type adapted to feed metal ingots to a melting pot, comprising an element carrying an ingot to be fed to the pot and driven by the weight of said ingot, gearing driven by said element, a star wheel driven by said gearing, and an escapement lever driven and oscillated by said star wheel, a brake element oscillatably driven by said escapement lever and having a friction surface, a friction lock lever adapted to engage said friction surface, a float-operated lever operatively associated with said friction lever, whereby to compound the leverage and to increase the sensitiveness of operation of said friction lock lever, and means for varying the space relation required for sensitiveness in operation between said brake element and said lock lever.

3. A feeding device of the type adapted to feed metal ingots to a melting pot, comprising a casing, an element carrying an ingot to be fed to the pot and driven by the weight of said ingot, gearing driven by said element, supports for said gearing, a star wheel driven by said gearing, and an escapement lever driven and oscillated by said star wheel, said supports being sustained in said casing and located to penetrate the plane of operation of said lever, the form of said lever being adapted to permit said supports to extend from the rear to beyond the front surface of said lever,

whereby to substantially decrease the magnitude of space required for said feeding device, a brake element oscillatably driven by said escapement lever and having a friction surface, and a friction lock lever adapted to engage said friction surface whereby to stop the movement of said ingot.

4. A feeding device of the type adapted to feed metal ingots to a melting pot, comprising a casing, an element carrying an ingot to be fed to the pot and driven by the weight of said ingot, gearing driven by said element, supports for said gearing, a star wheel driven by said gearing, and an escapement lever having a support and being driven and oscillated by said star wheel, said gearing supports being sustained in said casing and located to penetrate the plane of operation of said lever and being arranged with said lever support in a substantially straight line, the form of said lever being adapted to permit said gearing supports to extend from the rear to beyond the front surface of said lever, whereby to substantially decrease the magnitude of space required for said feeding device, a stop element operatively associated with said escapement lever, a lock lever 7 iclriven by the weight of-v said ingot, gearing driven ?by'said element, a star wheel driven by said gearing, an escapement lever driven and oscillated "byxsaid star wheel, a brake element oscillatably driven by said escapement lever and having a friction surface, and a friction lock lever adapted to engage said friction surface, whereby to stop the movement vof said ingot.

6.-In an automatic feeder mechanism of the .10 type adapted to feed metal ingots to a melting

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