US979196A - Multiple power-rammer. - Google Patents

Description

H. M. PLAISTED. MULTIPLE POWER BAMMER. APPLIGATION FILED sEPT.1a, 1909.

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H. M. -PLAisTEn MULTIPLE POWER BAMMER.

APPLICATION FILED SEPT. 13, 1909.

979,196. Patented 1380.20., 1910.

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I'ARQLD 141. ELAISTED, OF GRANITE CITY, ILLINGIS.

MULTIPLE POWER-RAMMER.

Application filed September 13, 1909.

To alt ltai/wm it may concern:

le it known tnat I, Hattem) M. PLais'rnD, a citizen of the Trlnited lttates, residing at Granite City, in the county of Madison and State of illinois, have invented certain new and useful linproyements in lilultiple Power-lamniers, of which the following is a specification.

My invention concerns improven'ients in power ranuners adapted for employment in compacting the sand in the molds, its leadinksaim bcir he elimination of a number of objectionable features in the devices now on the market and presented for public approvai.

in my new form of device, the individual rammers or stamping feet are divided into grcups operaned successively, whereby to secure a better coinpacting and ramming effect than as if the plungers were all forced down together. n my appliance, the sand has u chance to work somewhat sidewise, which results in a more iiniform density in the flask and also le -ns the reaction on the machine. 'llc secure the best etl'ect the rainmers are made .nall and are spaced closely together in ord r that they may work well into the curves of the pattern. instead of usino' compre 'ed air on both sides of the ers associated with and operating carers, which arrangement necessitates an a"'-tight connection at the lower ends the tubes or chambers in which the plungcrs reciprocate, the pistons and rammers in devices embodying my invention are actuated by subjecting one side only of the pi ons to the action of compressed air and sucticn. the other sides of such pistons being acted on by atmospheric pressure. By such means the pistons and ramming feet are forced down under suitable pressure and are raised by the action of the suction, that is, by lowering the pressure on the tops of the pistons whereby to make the same less than that of the atmosphere. rlhese, with other features of novelty and improvement, can be fully understood from the following detailed description of a preferred embodiment of the invention which is illustratcd in the accompanying drawings forming part of this specication, and throughout the various views of which like reference characters refer to the same parts.

ln these drawings,-Figure 1 is a partial elevation and partial section of my improved power rammer, illustrating the action of the Specification of Letters Patent.

Patented Dec. 2t), 1910.

Serial No. 517,442.

same en the sand in a mold flask; Fig. 2 is a plan view of the construction shown in Fig. 1; Fig. 3 is a fragmentary elevation of that end of the device equipped with the handle for operating the valve; Fig. 4 is a vertical section on line -d of Fig. 1; Fig. 5 is an enlarged view of one of the rammers or stamping members, and illustrates the chamber or casing partially broken away to more clearly show the internal construction; Fig. 6 is a horizontal section through the device on an enlarged scale, illustrating the zigzag or wave-like partition or wall between the two chambers supplied with the pair of groups or sets of plunger tubes; and F ig. is a section of the valve and its casing, showing the valve in a position connecting both sets of tubes to the atmosphere.

Referring now to the drawings for an understanding of the construction illustrated therein, it will be noted that the mold flask has the pair of longitudinal walls l0, l() cross connected at intervals by the transverse bars 11, 11, the power rammel' being mounted on a pair of channel tracks 12, 12, and adapted for movement thereon so that the ramming feet or stamping slices may be brought over all parts of the mold and its sand contents. The rammer, thus movable on the top flanges of the parallel tracks 12, 12, consists of a casting 13 supplied with four flanged wheels or rollers 14, the treads of which are adapted to roll on the top surfaces of the upper flanges of the channel tracks. To facilitate the mounting ofth-ese rollers upon this casting, the latter may be provided with a plurality of outwardly eX- tended arms 15, on which the rollers may be suitably mounted and supported. ln order that the rammer may be held tinedly in position on these tracks during the ramming operation, the casting 13 has flanges 1G at its opposite ends underlying the top flanges of the tracks and provided with set screws 17 adapted to bear against such flanges and hold the rammer immovably in positionfor operation on the sand 18 in the mold, in which any suitable pattern 19 may be embedded. The casting or member 13 is hollow and is divided into two chambers or compartments 2O and Q1 by a thin zigzag or serpentine partition or wall 22, each compartment near the side of the casting having an upwardly extended passage 223 and 24, respectively, coimnunicating therewith. The bottom of this main casting or member 13 has a considerable number ot' cylindrical recesses 25 extended iuawardly .thereinto beyond the chambers t1() and 2l., such cylindrical holes receiving the upper ends ot a plurality ot' vertical 'tubes 25, all of which pass through one or the other compartment 2t? or 2l, being apertured in its side at 2T to etlect communication between the particular chamber or compartment through which it passes and the interior ol' the tube. The lower end ot each ot' these tubes or casings has a bushin litted therein and axially apertured for the reception and reciprocation therein of a rod or shat't 29 having at its lower end a rammer or stampingtootththe upper end ot each rod or shat't being equipped with a pair ot' pistons or plungers 3l and having an airtight tit with the cylindrical inner surface ot the tube or casing. Near its lower end, each ot these tubes has one or more apertures 8?) (Fig. l) to obtain communication with the external atmosphere, so that the under surface oit the piston 3Q is at all times subjected to atmospheric pressure. The particular arrangement and disposition ot these tubes and. ra mmers with respect to the two compartments 2O and 2l is clearly indicated in Fig. G, substantially halt of the same being associated with each oit such compartments.

On top ot the casting 125, l bolt a valve casing Bt having' a conical valve seat 35 in which is mounted and adapted to turn a conical valve 3G having extended transversely therethrough two curved passages 37 and 3S (Fig. il), the valve being maintained in suitable association with its seat by a coiled expansion spring 39 acting on the head et the valve and mounted between the latter and a gland Ll screwed in the side of the casing. The valve stem Ll-l protrudes through this gland outside oi' the casing and has keyed thereon a mutilated gear it?, with the teeth otl which mesh those otl a toothed segment #t3 lifted on a rotatable shaft it revoluble in suitable bearings and equipped with a downwardlv-extended actuating handle a5. It should therefore be apparent that by swinging the handle t5 the valve 3G may be oscillated to change the connections or arrangements ot' passages in the valve casing. The hollow interior ot the valve casing '-l is connected above the valve to a pipe --l-t connected to any suitable means for creating l suction or producing a pressure less than that of the external atmosphere. The cavity within this valve casing` 3st has a lateral branch t7 connected to a supply pipe 48 which is in communication with a device, not shown, tor compre sing air or supplying steam or the like. under pressure, this pipe ttl being equipped, as is indicated in Figs. l and 2, with a shutotll valve 14.9. ttt one side ot the valve 3G, the cavity or recess in the valve casing has a passage extended downwardly and connnunieating with the upper end ot the passage 23, the opposite side ot the easing having a similar passage 51 in communication with the passage Q4. Bts is indicated perhaps most clearly in Figs. l and 7, the casing Slt, near the top part ot the valve llt), has two small ports 52 and on opposite sides otl the casing and leading to the outer air. lt should also be noticed, as is shown in these same iigures, that the valve seat is cut away on opposite sides at the points 5t and to permit the air to pass through passages 37, and 38, 53, respectively, iter a purpose hereinafter indicated.

rlhe operation of tl improved raminer is practically as t'ollows: i'lssum'ing that the .tiask or mold casing l() has been supplied with the sand 1S and a pattern it) has been embedded therein, the set screws 1T ot the ramming device are loosened and the whole appliance is rolled along on the channel tracks l2 until all ot the ramming teet or stamping members are above one of the spaces between a pair ot the crass bars ll connecting the opposite sides oit the tlaslr, as is indicated, tor example, in Fig. et, the number ot' such ramming elements being so chosen and the members so arranged that they can readily etlect the entire rannning operation between a pair of such cross bars without moving the device on the tracks. lllhen the rammer has been properly brought to position, the retaining screws 17 are turned so as to hold the appliance immova bly in place during the ramming operation. lt is to be understood, ot course, that to facilitate and. ellect this travel of the rammer, the pipes LLl-G and l-S are either made tlcxible or supplied with tlexible connections, as would obviously be necessary tor this purpose. rssuming that the valve 49 is open, the handle i5 is swung to the full-line position shown in Fig. 4l, el:- t'ecting the turning ot the valve 36 so as to bring about the connection et the passages as indicated in this ligure. The con'ipressed air, or other luid under nfessure, passes from the pipe 'fl-S through the valve 49 andv passage 4,7, through the curved port or passage 38 ot the Yalve, and thence through the registering passages 5l and 2st to the chamber or compartment. 20, such fluid entering the plurality ot tubes 2li tln-ough the apertures Q7 and acting upon the top surlfaces ot' and forcibly pressing down the pistons 31, which, as will be readily umlerstood, are directly connected with the shatts or rods 2) and the stamping teet, or rammers 30. rlhe result ot this action ot' the compressed luid is a forcible chmnward pressure ot these rammers, that is, one halt ot the total number ot rannners. on the sand in the mold, the pressure et' the (luid on the top sides ot the pistons 3l he' souuwvhat greater than the atmospheric pressure acing on the bottom surfaces of the pistons t the same time that these rannners are descending, the ranimers of the other group are beingI lifted or raised, because the suction appliance, acting through the pipe 46, valve port 3T, passages 50 and Q3, compartment 2l and the interior of the tube 26, operates to reduce the pressure on the top surfaces of the pistons bl below that of the atmosphere acting on the bottoni surfaces of the pistons Consequently', all of the rannners associated with the chamber Q() are raised by the atmospheric pressure, as will be readily understood. The operator then swings the handle Ll5 to the dotted-line position shown in Fig. 4f, and during such movement of the handle, the valve assumes the position indicated in Fig. T, which, as should be obvious, establishes,communication temporarily, or momentarily, between both of the chambers 2O and 2l and the outer air. permitting the escape of the compressed fluid from the chamber 2l and the entrance of the outer air into the chamber "30. while the connection with the suction and with the supply of compressed fluid is cut ott by the body of the valve, as is clearly indicated. When the handle has reached the dotted-line position, however, the port 37 has moved sufficiently to establish connection or communication between the passages 4T and 50, causing the entrance of the compressed fluid into the chamber 2l and the connection of the chamber 2O with the suction appliance, causing a reversal of the operations above described, that is, compelling a forcible descent of the pistons previously raised and the elevation of the pistons and raminers previouslyv pressed down. This operation and movement of the valve through its actuatinghandle can be continued until the sand in the mold flask has been sulficiently compacted and condensed, and when it is desired to elevate the entire number of rannners. it is merely necessary to close the valve et), thereby shutting off the supply of compressed air or steam, and moving or rocking the valve 3G so as to apply7 the suction appliance to first one set of tubes and then the other, the atmospheric pressure thereupon causing the elevation or raising of all of the plungers and maintaining them in that position. After this has been accomplished, the ramnier can be moved along on the tracks. as will be apparent, so as to bring the stamping feet over a new section of the mold.

Consideration should be paid to a number of features of this device, among which may be mentioned Lhe fact that no air-tight connection is maintained between the bushings QS and the rods or shafts so that any cutting of the bushing or rod due to the elevation of sand on the latter in no way interferes with the satisfactory and success- `ful operation of the appliance, the bushing 2S merely acting as a guide for the stamping feet during their reciprocations. lt is further to be noted that by dividing the rammers into groups and having them act successively, the sand is permitted to move somewhat sidewise and then be struck by the other group of rammers, which results in a more eflicient and satisfactory compacting or condensing of the sand in the mold flask. Attention is also directed to the fact that the air or fluid pressure on one side only of the pistons is varied or controlled to effect the sliding or `reci grocating action of the rammers, and that liy varying the pressure of the compressed fluid admitted to the passage 47, the stamping effect or force of the rammers may be modified without changing the action ot the suction which effects their raising or elevation.

Especial attention is directed to the fact that by establishing communication with the outer air at each oscillation of the valve, that is, permitting the compressed fluid to escape from the tubes and permitting the outer air to rush in and fill the partial vacuums in the tubes, a considerable saving is effected in the work necessary for the fluid compression appliance and-the suction apparatus. Owing to this peculiar construction, in which the tubes 26 are inserted in the casting 13 so that their upper ends extend beyond the chambers 20 and 2l, cushions are established in these ends of the tubes so as to diminish and cushion the shocks due to the upward movements of the pistons and attached rammers.

It is one feature of this invention that the rammers ought to be small in size and considerable in number to obtain the best results, and in order to permit the rammers to work well into the curves of the various patterns which may be employed. By opening and closing the valve 36 more or less, the amount of pris 1re on the descending pistons may be readily controlled to obtain the best results in each particular case, although ordinarily 'the control of pressure may be readily effected by the valve 49 if necessary.

The structural features of this particular embodiment of this invention have been entered into in the illustration and description with some degree of particularity, but it is to be understood, -and will be appreciated by those skilled in this art, that many minor mechanical changes may be made in this construction without departure from the substance of the invention and without sacrificing any of its substantial benefits or advantages. For instance, instead of a rocking valve of the type indicated, a slide valve somewhat similar to that of a steam engine may be employed if found to be desirable or feasible.

1 claim:

1. ln a rammel.' oi' the character described, the combination of a plurality of ramming members, and pneumatic means adapted to act successively upon the various members and on one end only of the members and in conjunction with the atniospheric pressure to alternately extend and retract said members, substantially as described.

2. ln a rainmer oi' the character described, the combination ot' a plurality of groups of ramming members, and pneumatic means to successively extend and retract each group, substantially as described.

8. ln a multiple power rammer ot the character' described, the combination of a plurality of chambers, a plurality ot groups ot' rammersa plurality of pistons connected to and actuating said rammers and slidable in said. chambers, and pneumatic means acting on one side only of said pistons to eX- tend and retract the groups of rammers successively, substantially as described.

t. ln a multiple power rammer of the character described, the combination ot a plurality of chambers, a plurality o't rammers, a plurality of pistons connected to and actuating said rammers and slidable in said chambers, and means to 'force said pistons and rammers in one direction by applying a pressure greater than atmospheric to one side oi" said pistons and to move said pistons and rammers in the opposite direction by malring the pressure on the same side of said pistons less than atmospheric, the opposite side of said pistons being subjected to the pressure of the atmosijihere, substantially as described.

5. ln a multiple power rammer of the character described, the combination of a pair of sets ot' chambers, av pair of groups of rammers, a pair of groups ot pistons connected to and actuating said rammers and slidable in said chambers, and means to force one group of said pistons and rammers in one direction by applying a pressure greater than atmospheric to one side otl said pistons and to move the other groups ot' pistons and remmers in the opposite direction by making the pressure on the corresponding sides oit their pistons less than atmospheric, the opposite sides otl all o1" said pistons being subjected to the pressure of the atmospliere, substantially as described.

6. in a device of the character described, the combination ot a pair of groups oi" piston chambers, a pair of sets of pistons slidable in said chambers and in communication with the atmosphere on one side, rammers operated by said pistons, a connection with a source of fluid under pressure greater than atmospheric, a connection with a suction appliance, and means between said connections and chambers adapted in one position to admit to the chambers of one group and on one side of the pistons therein a supply of said liuid to torce said raminers against the sand in the mold flash, said means at the same time connecting the chambers of the other group and the corresponding sets ot their pistons to said suction appliance to cause said second group ot pistons and rammers to move away from the flask, said means being capable olf reversing the connections specitied, whereby said groups of rammers may be alternately driven into and driven from the flask, substantially as described.

7. 1n a device of the character described, the combination of a pair ot groups of piston chambers, a pair of sets oii pistons slidable in said chambers and in communication with the atmosphere on one side, rammers operated by said pistons, a connection with a source ot' fluid under pressure greater than atmospheric, a connection with a suction ap pliance, and a single valve between said conncctions and chambers and adapted in one position to admit to the chambers ot one group and on one side of the pistons therein a supply of said fluid to iorce said rammers against the sand in the mold Hash, said valve at the same time connecting the chambers of the other group and the corresponding sides ot the pistons to said suction appliance to cause said second group oit pistons and rammers to move away from the flask, said valve being capable of reversing` the connections speciiied, whereby said groups of ram y mers may be alternately driven into and away from the flask, substantially as described..

8. in a device of the character described, the ctmibination of a pair oit' groups of piston chambers, a pair ot sets or' pistons slidable in said chambers and in communication with the atmosphere on one side, rammers operated by said pistons, a. connection with a source of tluid under pressure greater than atmospheric, a connection with a suction appliance, and means between said connections and chambers adapted in one position to admit to the chambers of one group and on one side ot' the pistons therein a supply of said vduid to force said rannners against the sand in the mold tiask, said means at the same ime connecting the chambers ol the other group and the corresponding sides ot' their pistons to said suction appliance to cause said second group oit pistons and rammers to move away trom the flash, said means being capable of reversing the conncctions specified, whereby said groups of rammers may be alternately driven into and away -trom the Hash, said means being constructed to connect the chambers of the two `groups with the external atmosphere during change from one ot said connections to the others, whereby to permit the compressed tiuid oi one set ot chambers to escape to the external atmosphere and to permit the outer air to e ter the chambers previously subjected te suction, siibstantiully as described.

i). in u power rammer of the character deseril. ed7 the combination of u plurality of compartments provided With fluid Cushions at their upper ends, pistons reeiprocable in said compartments, rzimniers operated by suid pistons, and means to Yury the fluid pressure in smid compartments on one side only of said gstons above und below ntmospherie pressure to cause their reeiprocutien, the oth r sides of said pistons being subjected to atmospheric pressure, substantiaH i us described.

HAROLD M. PLAISTED. ifitnesses 'YEXDELL C. FLETCHER, E. A. 1WALGr-nu.

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