US1089895A - Process of applying abrading material to grinding mechanism. - Google Patents

Description

J. A. BBGHTEL.

PROCESS OF APPLYING ABRADING MATERIAL 'I'O GRINDING MECHANISM.

APPLICATION FILED JANv 15, 1913.

mfimw Patented Mar. 10, 1914.

4 SHEETS-BHEET 1.

WITNESSES: IN V EN TOR.

W/w v V4 (A J. A 'BBOHTBL.

PROCESS OF APPLYING ABRADING MATERIAL 'IO GRINDING MECHANISM.

AZ-PLIUATION FILED JAN.15, 1913. j fli jgfigwfi Patented Mar. 10, 1914..

-; SHBE'1S-BHEBT 2.

2 a. I M 4 m M N W mnm H v 1 r a L w a.

L A. BECHTEL.

P11003555 0F APPLYING ABRADING MATERIAL To GRINDING msommsm. APPLICATION FILEDJAN. 16, 1918. g gggfigg Patentefl Mar. 10, 1914-,

4 SHEETS-SHEET 3.

m M m m" E J. A. BBGHTEL. PROCESS OF APPLYING ABRADING MATERIAL PO GRINDING MECHANISM. APPLICATION FILED JAN,15, 1913.

1,089,895 Patented Mar. 10, 1914.

4 SHEETS-SHEET 4.

ATTORNEY UNITED snares rirrnrrr carton,

JOHN A. BECHTEL, 0F TARENTUM, PENNSYLVANIA, ASSIGNOR TO PITTSBURGH PLATE GLASS COTEPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENN- SYLVANIA.

Specification of Letters Patent.

Application filed January 15, 1913.

Patented Mar. 10. 1911.4.

Serial No. 742,224.

To all whom it may concern:

Be it known that 1, JOHN A. Bnorrrnn, a citizen of the United States, residing at Tarentum, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Processesof Applying Abrading Material to Grinding Mechanism, of which the following is a specification.

The invention relates to a process for applying ahrading material to grinding mechanism, and involves the use of apparatus such as that illustrated and described in my co-pending application Serial No. 715,126, filed August 14:, 1912. The invention has for some of its primary objects the provision of a process wherein the amount of apparatus for its practice is reduced to a minimum, and of such simple character as to be easily operated by unskilled labor; the provision of a process wherein the abrading material is prevented from setting; the provision of a process in which the mixture of abrasive and water is circulated in such manner as to equalize the capacity of the system for all the grades employed; the provision of a process whereby that portion ofthe abrading material not suitable for the grinding work being done at any particular time is separated and held in readiness for future operations; the provision of a process in which the waste of ahrading material is substantially eliminated, and the provision of a process wherein abrasive of different degrees of fineness or the same degree of fineness may be simultaneously supplied to a plurality of grinding machines without interference.

One type of apparatus bywhich the process may he practised is illustrated in the aceoi'npanying drawings, wherein Referring first to the general arrangenient of parts as shown in Figs. 1 and 2, i\-.-:.L are grinding tables which may he of any approved type and driven in the usualmanner; 13- 15 and C-C are the runners ordinarily employed in the grinding of plate glass, which runners are 01 the usual construction and supported in the usual way; D-D are the troughs or drainage receptacles lying beneath and encircling the F is a drainage pit or sump to which the mixture of sand and water from the troughs D-D is conducted through the passages G; H is a rotary pump for carrying the mixture of sand and water in the sump F to the grading tank E; H is a bin containing fresh sand which is adapted to be supplied from time to time from the bottom of the bin to the sump F through the door I; and K-K are troughs leading from the grading apparatus to the two grinding mechanisms, such troughs communicating at their lower ends with transverse conductors Ti perforated on their lower sides and extending across the grinding tables so as to supply the mixture of sand and water uniformly over such tables. In the arrangement just described, one grading apparatus is illustrated as taking care of two sets of grinding mechanism, but it will be understood that this arrangement is merely illustrative,

and that the grading mechanism may be used with any desired number of grinding inechauisms dependip upon its capacity. In operation, the material supplied through the troughs K to the grinding tables, after use upon such tables is drained into the troughs D and returns to the pit or sump F from which it is pumped to the grading tank It by means of the pump H, so that the material is used over and over again, the material too linefor use being washed out over the top of the tank as hereinafter described, and fresh sand being supplied. from the bin H from time to time to take the place of i readily understood by rei'erence to figs. i and 5. The lower portion 1 of the grading tank E 1s conical 1n form, while the in s pump being provided with an inlet s e etior carrying the materialto be graded,

irons thesurnp' F to the pump, and has an "let pipe 5 leading intothe lower end of illustrated, two sets. oi pipes 6 and tion oi the tank and have connected to their ends which lead through the sides of the tank,.the flexible pipes 8 and 9. Either into troughs K leadingto the grinding mechanisms. The other flexible pipe or see which do not'lead to the troughs K pee ll. leading to the sump Susded in the cylind cal portion 2 of the it are pair-of flexible tubes 12, which open at their upper ends and at lower ends pass through the side of the "tan": and carry the flexible tubes 13. These flexible tubes 13 can be made to discharge either into the troughs K or into the boxes a The tubes 12 are suspended by means the cores lower end of each of the cords 13 being died with a chain 15 which may be to engage a securing device (not shown) whereby the upper ends of the flexibl pipes 12 may be held at any desired eleoverflow opening 16 provided :ent the upper edge of the tank, fromwhich. opening a pipe 1? (Fig.1 5) conducts the waste material such as mud and sand'too fine for use, tothe sewer or. some other waste receptacle.

portions 2 of the tank is an outlet pipe 18 .extendingdown into the tank as indicated serve a function to he hereinafter described.

As indicated in Fig. 3', the bottom of the sand bin H is'forined with converging walls 23--5E3, and the joining edges of these sidessiope toward the sunip F as indicated in Fig. "l. oi this arrangement, the a be readily conducted to being controlled by or the sandidown the characterfoi the grading apparatus portion 2 thereof is cylindrical, lhe it is driven-from. a motor (Fig. 5

Qrfiding tank E.. In the fornrof appa iroin diiierent levels in the conical por-" forced up through the gradin tank or both oi the pipes 8 and 9 may be directed s harge into the boxes 10 provided with,

1' passing over the pulleys 1e,

intermediate the ends of the cylindrical in dotted lines and governed by the valve 19,: andleading to the trough 20 are twobranches 21'. This trough 2O surround ng ditches D -D; underneath. the tables and l. In order to iainclined bottomof the'bin, the pipes 26 are provided along'the inclined sides of the bottom as indicated in Fig. 3,'and a third pipe 27 extends along theextreme lower edgeof the .bin. These pipes are supplied withwater outlets, and by this means the feeding of the sand out of the bin and to the sump F- is greatly facilitated,- and all of. the sand-in the bin may be fed .out without difiiculty.

The ball check valve 28 governs'the'openin at the lower end ofthe draining tank, sue ball valve being operated by means of the rope 29 extending-over the pulleys shown.

It will be seen that whenthe pump is operated, the material from the sum F is the'sand in the water is grade according to its size,- thelarger particles occupying a p'o sitionadjacent the bottom of'the tank, and the grades becominghfiner'and finer asv the.

top of the tank is approached. For the first 1 rough grinding of the plate of glass, the

coarse grades of'sand are required, and in the operation of the apparatus when the grinding is first-be un the flexible pipe 8 connected to the pipe 6 is introduced into the trough K, the other pipes 9 and 13 carrying the finer grades 01. sand and being in position so as to discharge into the box 10. W hen the grinding has progressed for a given time, and a finer grade of sand is re quired, the pipe or hose 8 is withdrawn from the trough K and the pipe or hose QIinserted in such trough. ,After thev grinding with thisparticulargrade has been concluded, the

upper end of the pipe or hose 12 is lowered to a position adjacent the'lower end of the cylindrical part 2 of the tank or tea level in the tank occupied by the exact grade de-. sired, and the pipe 13 is placed in the trough K,'.the pipes 8 and 9 at such time discharging into the box 10.- Asthe'grinding pro-' grosses and liner and finer grades of sand and are required, the pipe 12 is'raised step by step by means of chain 15 at the end of cord 13 until the finest grade of sand is. used, and the grinding operation is concluded. The several links-in the chain; not only serve to secure p'ipe12 in the proper position by engaging with the stop not shown, but it also enables the operator to determinetheexact position of the free end of theflexiblefipipe- 12 in the grading. apparatus so he "thereby knows the exact. gradejofabrasiye being de flivered to thei'grinding. mechanism at any stage of the oporation n is desirable'during'the opera-i911 s just describedthat the upward. velocity; inthe tank may be-such that none of the sand suitable for use shall be Washed through the. outlet- 16," and in orden to regulate this up- ;ward-velocity of the water through the up perpprtion of the tank and prevent a Waste ojfanyotthe' grinding sand, the-outlet pipe 18 controlled by the valve-19 is provided.

order to wash it out.

The opening of this valve 19 reduces the up- 'ard velocity of the water in the tank above the lower end of the pipe 18 to such an extent that only the mud and those portions of the sand unsuitable for grinding are washed away through the overflow 17. The mixture thus withdrawn through the outlet 18 passes through the trough 20 and thence through the pipe 22 to the trough or gutter I) (see l), and thence back to the sump F. The material thus withdrawn is therefore not wasted, but is returned for use, and the returning of the mixture to the gutter D performs a useful function in that it assistsin washing out the gutter and keeping it clean, thus reducing or eliminating the amount of clean water which would otherwise have to be. furnished to the gutter in The mixture of fine sand and water, because of its specific gravity, constitutes a better washing medium for the coarse sand in the trough than clear water. The placing of the valve 19 above the inlet to the pipe 18 is advantageous in that the head of water at the valve 19 and its velocity is reduced, thus reducing the cut ting action of the sand on the valve. Similarly the use of the trough 20 is advantageous, as the pipes 21 discharge into such trough at relatively low velocity, whereas if such pipes were connected directly with the pipe 22, the suction from such pipe 22, due to the added head, would increase the velocity. of flow pastthe valve 19 and the consequent cuttingaction of the sand.

It will be seen from the foregoing that the operation of the apparatus is substantially continuous and that the amount of waste is reduced to a minimum. Any desired quair tity of any desired grade of sand may be withdrawn from the tank at any time without disturbing the grades above or below the, point of withdrawal, and the apparatus is always in condition for use. When the grinding mechanism is not beng operated, all of the pipes or hose 8, 9, and 1.3 discharge into the box 10, and the material is returned to the sump F and again circulated through the apparatus. The pump H may thus be made to operate continuously, regardless of the operation of the grinding mechanism, and as a result, the sand in the water is maintained continuously in suspension, and there is no clogging of the parts due'to the mttling of the sand. v

It will also be readily understood that no matter whether one or more grinders are in operation or Whether. no grinder at all is in operation, the discharge from the various pipes leading from the grading tank remains constant, thus insuring the same upward velocities in all of the liorizontal planes in the grading tank so that irrespective of the clniracter of the work that is being done, the val. will always lie at approximately the same position in the grading apparatus, thus insuring a uniformity of operation not easily otherwise obtained.

It will also be apparent that due to the small capacity of the lower part of the conical portion of the'cone, the capacity of the grader to hold the larger grades of coarser particles is comparatively small in proportion to that part of the grading apparatus which holds the finer portions of grading material; but inasmuch as these coarser grades are continuously discharging from the lower portion of the cones into the sump 1*, the capacity of the system to hold the lower grades is increased by the capacity of the sump F. This increase of the capacity of the system is very advantageous as it enables the apparatus to be operated under widely varying conditions as regards the amount of coarse sand that is. introduced into the system from the bin H. If it were not for this feature of the apparatus and too great a quantity of sand was introduced into the system, the coarse sand would accumulate in the bottom part of the grader E and seriously interfere with its operation. On the other hand, the upper portion of the tank above acts as a collector or trap for fine sand, such fine sand accumulating until the desired proportion of sand to water necessary for the best results in grinding is secured. This upper portion of the tank thus constitutes a supplemental grader superposed upon the lower part of the tank.

Furthermore, the labor of getting the sand'into suspension again, incident to an intermittent operation, is eliminated,.and the apparatus is in condition for operation just as soon as the grinding mechansm is in 105 shape to receive the sand. Another advantage incident to the process is due to the factthat a plurality of grinding mechanisms may be fed from the same grading apparatus, and this operation may be carried on 110 whether the stage of grinding is the same inv the various grinding mechanisms or not; that is, rough grinding may be carried onin one grinding mechanism while fine grinding is being carried on in another mechanism, 115 such function being incident to the fact that one grade may be withdrawn from the apparatus without interfering with the position of another grade.

As a further function incident to the use 120 of the regulating valve 19, it will be seen that the use of this valve permits any de-' sired upward velocity of fluid inthe tank below the lower end of the pipe 18 without I increasing the velocity above such lowerend 125 or without washing away any of the sand suitable for use, through the overflow 16. This permits the changing of the speed of the pump H to give any desired grade from the pipes 6, 7 or 12, without increasing the overflow and consequent waste. It will be seen that all of thesand inthe system is always ready for use, so that the capacity of the system is governed only by the combined capacity of the sump and grading tank.

Another great advantage of the process is that no valves are required to regulate the character of the mixture, which, from the various operations in the tank, -"goes either to the sump or the grinding table, it being extremely diflicult to get a valve which will stand the cutting action'of the sand and remain tight, and it is extremely important that when the finer gradesof sand are being conducted to the grinding table, io'ne of the coarser grades should be allowed to get onto the grinding table, as this would greatly impair the quality ofthe work done.

It will also be readily understood that by use of the swinging conductor 12 which is adapted to be raised and lowered through a wide range in the grading tank, it is pos si is, at will, to withdraw any of the grades from the grading tank without disturbing any of the other grades or without with drawing all of any of the grades contained therein, so that it is possible by gradually and uniformly raising the end of the fleiii ble conductor 12 while still. retaining a large quantity of all of the grades of the abrasive accurately gradedv in the grading vessel, to withdraw successively a portion of each of these grades ranging from the coarsest to the finest, each grade following the precedrne byimperceptible changes so that the character of the surfaces being ground on the grinder can be readily brought frointhe state of roughness to the state of extreme fineness desired, in the most natural manner and in the shortest possible period of time. It will be apparent that the invention is capable of embodiment in various forms of structure without departing trom'the spirit of the process.

may be similarly varied to supply any desired number of grades. The grading tank shown is of conical fOrni-anddischarges by gravity, but it will be apparent that this is not necessarily the case, as the mixture might charge from such pipe be directed to grinding mechanism. Similarly as to the feature of continuously circulating the new terial through the tank W1thOUt-PQSS1Dg to "the grinding machine when such grinding machine is out of operation, such method of The number of grinding mechanisms fed from a single grading tank- 'may be varied to suit conditions, and the a number of withdrawing pipes in the tank operation being just as applicable to a grad-I invention. 7 p

The process is obviously not limited in its application to the grinding of the faces of sheets of plate glass, but may be utilized in other glass grinding or smoothing operations, and on various substances-besides glass wherein abrasive-and'water are employed, the drawings and description be- Other avithcut departing from the spirit of the ing merely illustrative of one important use of the process. In some cases it may be desirable to use only one grade of abrasive with each grinding or smoothing HIQChEL nism and shift the article from a mccha-I nism supplied with one grade of abrasive.

to another mechanism supplied with an other finer grade of abrasive, the number of shifts and mechanisms being dependent upon the character of the surface being reduced. v n Having thus described my invention, what I claim as new and d sire to secure by Letters Patent, is the following:

1. The method of applying abrasive to grinding mechanism, which consists in grading the abrasive in suspension in water a receptacle, conducting any desired grade to the grinding mechanism, collecting the drainage of abrasive and water from' the grinding mechanism, conducting portions of the grades m the receptacle not being used to the drainage collected and returning the drainage to the grading receptacle during the period in which the said desired grade is being conducted to the grinding mechanism, the

said operation being conducted in an uninterrupted cycle.

2. The. method of applying abrasive to grinding mechanism, which consists in sup- I plying a mixture of one of the grades of the abrasive and a liquid from a grading receptac-le to thegrinding mechanism and re-- turning the mixture'to the receptacle in an uninterruptedcycle, while maintaining the other grades of. abrasive in the receptacle in suspension in the liquid, and simultaneously circulating such other grades to a position removed from the receptacle and back through the receptacle to their original'positions in the receptacle.

3. The method of handlingiabrasive for grinding mechanism, which consists in grading the abrasive in suspension in water in a receptacle, conducting mixture of the abrasive and water to the grinding mochanisni and thenceto a drainage receptacle and back-to the grading receptacle in an uninterrupted cycle during the grinding operation, and continuously circulating the mixture of abrasive and water to the drainage receptacle and back to the grading receptacle when the grinding operation is not being carried on, the portion of the abrasive in the receptacle at such time being graded by the circulation.

4. The method of applying abrasive to grinding mechanism, which consists in collecting a mixture of abrasive and water from a grinding mechanism, forcing such mixture upward through a grading tank containing a mixture of abrasive and water, thereby grading the mixture, conducting a portion of the mixture from one level in the tank to the grinding mechanism, and simultaneously returning other portions of the mixture from other diiterent levels in the tank to the mixture collected fronrr the grinding mechanism, the cycle being sub stantially a continuous and uninterrupted one aslong as the grinding continues.

5. The method of applying abrasive to grinding mechanism, which consists in col lecting a mixture of abrasive and water from a grinding mechanism, forcing such mixture upward through a grading tank containing a mixture of abrasive and water, thereby grading the mixture, conducting a portion of the mixture from a level intermediate the top and bottom of the tank back to the mixture collected from the grinding mechanism without passing to such mechanism, whereby the upward velocity of the water in the tank above the said level is reduced, and conducting portions of the mixture in the tank below and above the said" levelsuccessively to the grinding mechanism, the operations of forcing the mixture upward through the grading tank, conducting a portion of'the mixture from the said level in the tank; and conducting another portion of the mixture to the grinding mechanism being carried on simultaneously.

6. The method of applying abrasive to av plurality of grinding mechanisms operating simultaneously, which consists in gradlng the abrasive in suspension in water in a receptacle, simultaneously conducting por tions of the .diiferent grades or the same grade to the different grinding mechanisms, dependin upon the stage of grinding of each madhine, efid, returning thedrainage from the grinding mechanisms to the said receptacle the circulation from the receptacle to the grinding mechanisms and back being an uninterrupted one.

7. The method or applying aln-asire to a plurality of grinding mechanisms operating ,imultaneously, which consists in collecting the mixture of the abrasive and water from the various-grinding mechanisms, forcing such mixture upward through a grading tank containing a mixture of abrasive and water, thereby grading the mixture, and conducting portions of the mixture from ditt'erent levels in the tank simultaneously to the said grinding mechanisms, the said operations constituting a continuous cycle.

8. The method of applying abrasive to a plurality of grinding mechanisms operating simultaneously, which consists in. collecting the mixture of the abrasive and water from the various grinding mechanisms, forcing such mixture upward through a grading tank containing a mixture of abrasive and water, thereby grading the mixture, conducting portions oi": the mixture from different levels in the tank simultaneously to the said grinding mechanisms, and at the same time conducting portions of the mix ture in the grading tank containing grades of abrasive not being used backto the drainage collected from the various grinding mechanisms without passing to such mechanisms, the said operations constituting a continuous cycle.

9. The method oi :qmlying abrasive to grinding mecl'ranism which consists in collecting the mixture oi abrasive and water from the grinding mechanism, eliminating the superfluous water and finest abrasive from 'the mixture, returning the coarsest abrasive to the grinding mechanism during the period in which such. coarsest abrasive is required in the grinding operation, and returning such coarsest abrasive directly to the mixture collected from the grinding mechanism without passing to the grinding mechanism, when such coarsest abrasive is 'not required by the grinding mechanism, the said operations constituting a continuous cycle.

In testimony whereof I have hereunto signed my name in the presence oi. the two subscribed witnesses.

JOHN A. BECI-IEEL.

Witnesses:

Ln'rrrm A. M'i'uus, Anonwon'rn M A max

Images