US2651888A - Snagging grinder - Google Patents

Description

Sept. 15, 1953 s. E. coMsTocK, 3RD 2,651,838

SNAGGING GRINDER Filed May 15, 1952 2 Sheets-Sheet 1 m V /0 a INVENTOR. 6ve 5 E COM57'0C/(3m Patented Sept. 15, 1953 new UNITED STATES FA'i'Ehi'l' @FFICE SNAGGING GRINDER George E. Comstock 3d, Holden, Mass., assignor to Norton Company, Worcester, Mass., a'corporation of Massachusetts Application May 13, 1952, Serial No. 287,530

8 Claims. 1

The invention relates to snagging grinders. One object of the invention is to provide a snagging grinder which can be operated with ttle effort. Another object is to provide a thoroughly safe snagging grinder. Another object is to provide a snagging grinder of rugged yet simple construction and which is versatile so that it can snag small or large billets, short or elongated castings and can therefore be used for a variety of purposes in a steel plant or foundry. Another object of the invention is to provide a snagging grinder capable of operating with higher pressures between the grinding wheel and the work piece than have hitherto been achieved in actual practice. Another object is to provide an economical grinder from the standpoint of grinding cost per unit volume of work. Another obiect of the invention is to provide a power operated snagging grinder so arranged that the operators station is internally of the area occupied by the machine whereby the grinding wheel may be driven to send the detritus away from the machine and a dust collector systern for one or many machines can be installed to collect the detritus without being in the way of the operator or operators. Another object is to provide a snagging grinder of such characteristics that it is movable along a track to produce the traverse between grinding wheel and Work piece whereby several machines can be Figure 2 is an axial horizontal sectional view Figures 6 and '7 are fragmentary views illustrating modifications of the invention.

Referring first to Figures 1 and 3, secured in any suitable manner to the floor In of the building where the grinder is located is a pair of parallel rails H H forming a track. The rails II can be embedded in a concrete floor and/or wooden ties can be used as in the case of a railroad track. A platform 12 constitutes the body of a car which runs on the rails l I; heavy bearing brackets is are secured to the under side of the platform 52 and receive axle shafts l l on which are flanged wheels it: which rest upon the rails ll.

One of the axles "it has secured thereto a sprocket gear it which can be driven by a chain extending from the gear 55 to a sprocket pinion 68 driven by a fluid motor !9. This fluid motor is is reversible and is secured to a plate which is secured to one end of the platform i2.

Referring now to Figure l, a valve lever 2i a short portion 22 extending at right angles to the upstanding part of the valve lever and the outer end of the short portion 22 is connected by a link 23 to a flange 2d projecting from the cap 25 of a valve casing lit. A valve piston 2'3 with three lands is movable in a bore in the casing 26 which the lands snugly fit. The valve casing 2% has a pressure channel 28 a pair of exhaust channels 2t. 1' provide four duplicate valve casings '25 with the same moving parts and channels and these are aligned and bolted together with bolts 3! Each valve casing 2% has a pair of channels 3! and 32 for sending oil to and receiving oil from the piece of apparatus which the particular valve controls. Referring now to Figures 1 and 3, I provide a tank 33 which contains a supply or" oil which is the hydraulic fluid to actuate the apparatus. 011 the cover of the tank 33 is a motor (i whose motor shaft is coupled to a pump 36.

The output side of the pump 36 is connected to piping which is connected to all of the pressure channels 28 by being connected to one thereof through an end cap 33 since these pressure channels 28 are cross connected to each other by a cross channel it which extends through each valve casing 25 and between them, suitable gaskets being provided to prevent leakage and the outer ends of the cross channel being blocked by the end cap 38 and another end cap il at the other end of the set of valve casings 25. Exhaust piping t2 extends to the end cap ll and is connected to a cross channel which cross channel 63 likewise extends through each valve casing 26 and between them connecting all of the exhaust channels 29 together, and the same gaskets and the caps es and Li: prevent leakage. The piping 32 runs to the tank 33 to return the fluid thereto. In the piping 31 is a relief valve 49 the exhaust side of which is connected to the tank 33 and thus the system can be set to cause each of the pieces of apparatus to exert just so much force and no more. The intake side of the pump 36 is connected to the bottom of the tank 33 by means of piping 45.

The control apparatus has four valve levers, the valve lever 2! already identified and valve levers 52, 53 and 54; these are all alike and their connections to valve pistons corresponding to the valve piston 2'! are all alike, in fact Figure 4 could be a section through any of the valve casings. Whenever any of the hand levers 2!, 52, 53 or 59 is moved to the right, Figure 4., the channel 3! is connected to pressure and the channel 92 is connected to exhaust.

The fluid motor I9, adapted to be operated by oil under pressure, is connected by piping 58 to the channel 3| and by piping 51 to the channel 32. When oil flows to the fluid motor i9 through the piping 58 and returns from the motor I9 through the piping 5'I, which is when the operator sitting upon the stool 89 draws the lever 2I towards him, the motor I9 revolves in such direction as to move the car to the operators left which is to the right in Figure 3, conversely when the operator pushes the valve lever 2I away from him, oil goes to the motor I9 through the pipe 5! and leaves it through the pipe 56 and this causes the car to move to the operators right, which is to the left in Figure 3.

Referring to Figures 1 and 3, secured to the top of the platform I2 of the car is a base casting 63 having a massive central upstanding forked portion 63 and. a pair of lateral upstanding forked portions 95. With its lower end located in the forked portion 96 and connected thereto by a heavy rock shaft 99 is a large upstanding rocker 6? having a forked top 68. Extending through the forked top 88 and connected thereto by a pin 99 is a horizontal overhead lever I0. A large depending lever II of generally open box shape is connected by a pin I2 to the front of the lever 79, the pin 72 extending through and between the sides of the lever II and through the lever "59. A grinding wheel I5 is located between a pair of disc-like enlargements E6 of the bottom of the sides of the lever II and is ournalled therein on an axle shaft TI to which the grinding wheel and also a double pulley I8 are secured.

Referring now to Figure 2, the disc-like enlargements it are connected by integral peripheral connecting portions 79 which form with the enlargements I9 a Wheel guard for the grinding wheel l5 to keep the sparks and swarf from spraying upon the operator; the grinding wheel is intended to rotate clockwise as viewed in Figure 1 although because the stool 69 is not in line with the grinding wheel I5 that is to say is well removed from the plane of rotation of the grinding wheel I5, the grinding wheel could rotate counter-clockwise without great detriment but it is preferred not to have the swarf land upon the machine or any part thereof.

Referring now to Figure 1, one of the sides of the lever II has an upwardly and rearwardly extending portion 89 while the opp osite side of the lever II has an upwardly and rearwardly extending offset portion 8I and located between these portons 39 and 8| is a bored enlargement 82 of a plate 83 and a pin 84 extends through the ends of the portions 80 and BI and through the bored enlargement 82 of the plate 89 thus pivotally mounting the plate 83 for movement up and down. Mounted on the plate 33 and secured thereto by bolts 85 is an electric motor 88 having on its armature shaft 81 a double pulley 98 connected by belts 89 to the double pulley "58. Of course the pulley 88 is keyed or otherwise fastened. to the shaft 81, the pulley I8 is keyed or otherwise fastened to the axle shaft ll, and (see now Figure 2) a bushing 99 extending through the hole in the grinding wheel :5 is keyed to the axle shaft 'I'I while a nut 9I mounted on the threaded end of the bushing 99 and the opposite flanged end of the bushing 99 grip the sides of the grinding wheel 15 so that it can be driven by the rotation of the axle shaft ll, and as is customary suitable blotters, not shown, are interposed between the side of the wheel and the nut Stand also between the side of the wheel and the flanged end of the bushing 99. Suitable bearings 92 and 93 are provided in the disclike enlargements 16 to journal the axle shaft l'l' and a nut and Washer 94 secures the pulley '58 to the axle shaft 11 which is tapered at the end as shown. Thus whenever the motor 35 is energized, the grinding wheel 15 will be rotated, and I provide means to tighten the belts 89 at will as follows.

Extending through a boss 95 at the front end of a forwardly extending portion 96 of the lever II is a stud 91 having a vertically bored enlargement 98 in threaded engagement with a screw 99 passing therethrough and the screw 99 has a reduced upper end I00 which extends through a hole in the plate 83 and the reduced end I99 just fits the hole so that the resulting shoulder on the screw 99 can thrust the plate 83 upwardly while a washer and cotter pin IIlI on the upper end of the screw 99 serves to hold the parts from disengagement. By turning the screw 99 to raise it the belts 89 are tightened.

On the rear end of the lever I9 is a rearwardly extending forked enlargement I95 receiving the enlarged end I06 of a piston rod I01 Whose piston, not shown, is located in a cylinder I99 having a head III] with an integral shaft III extending therefrom, the shaft I I I having on the lower end thereof an enlargement I I2. The rocker 61 has a rearwardly extending forked portion H3 receiving the enlargement II2 through which and through the forked portion extends a pin Il thus articulating the cylinder I09 to the forked portion II3. Similarly the piston rod I9! is articulated to the rearwardly extending forked enlargement I05 by means of a pin II5 extending through the enlargement I05 and the enlarged end I06.

Between the upwardly and rearwardly extending portion 80 and. the bored enlargement 82 is an enlarged end II8 of a piston rod II9 having a piston, not shown, in a cylinder I2! having a head I22 with an integral shaft I23 extending therefrom, the shaft I23 having an enlarged end I24 located in the rearwardly extending forked enlargement I05 and connected thereto by a pin I25 passing through the forked enlargement I95 and the enlarged end I24. Thus the cylinder I2I is articulated to the forked enlargement I95 while the piston rod I I9 is articulated to the portion 89 of the lever II.

The rocker 61 has on each side thereof a pair of laterally extending integral parallel flanges I39, each pair receiving the enlarged end I 3I of a piston rod I32 having a piston, not shown, in a cylinder I34 having a head I 35 with an integral shaft flanges its are articulated to th'e'pistoirro'ds I3 2 and the cylinders forked portions 55. v

Referring now to Figure 5, the several channels 3| and 32 are differentiated by the identification, below each pair, of one of the valve levers 2!, 52, 53 and 54. The channel 3! of the valve controlled by the lever 52 is connected to piping I4! I34 are articulated to the and the channel 32 of the same valve is connected to piping M2. The piping MI is connected to hoses M3 and M4; the hose M3 is connected to the bottom of the left hand cylinder I34 (Figure 3) and the hose Hi l is connected to the top of the right hand cylinder [3d (Figure 3). The piping M2 is connected to hoses M5 and M6; the hose IE5 is connected to the top of the left hand cylinder I3 5 while the hose M5 is connected to' the bottom of the right hand cylinder I35.

The channel 3| of the valve controlled by the lever 53 is connected to piping i5! and the channel 32 of the same valve is connected to piping 52. The piping I5] is connected to a hose which is connected to the top of the cylinder while the piping I52 is connected to a hose 55% which is connected to the bottom of the cylinder W9.

The channel SI of the valve controlled by the lever 54 is connected to piping l6! and the channel 32 of the same valve is connected to piping E62. The piping [Si is connected to a hose iSi which is connected to the front end of the cylinder lZl while the piping M2 is'connected to a hose Hid which is conn cted to the front end of the cylinder I2 I,

The motor 3 1 is energized by a cable llli while the motor 8t is energized by a cable ill. The cable ill and parts of the piping I5], 152, [Bi and lti. are carried by a vertical support it. extending upwardly from the car platform i2 This support H2 has a rearward extension lit supporting a hose H5 which receives both cables lit and ii! and extends to a swivel support i'it mounted on a stanchion Ill secured to the floor it}. Because the hose H5 is much longer than the distance between the extension [l3 and the swivel support H6 when. the former is right opposite the stanchion l'il, the car can move quite a distance along the rails it without breaking the hose H5 or the cables lit and iii therein. The operator of course has available switches controlling the stopping and starting of the mo tor but it has not been deemed necessary to illustrate these.

it will now be seen that with the hand lever M the operator can move the car to a position to grind any part of the billet or steel plate or whatever it is that needs to be ground along the length thereof, that by means of the hand lever E2 the operator can tilt the rocker 6? which is an inverted pendulum to tilt the grinding wheel 15 in order to use the corner thereof to dig deep into the metal, that by means of the hand lever 53 the operator can raise and lower the grinding wheel and by means of the hand lever 54 he can move it towards and away from the car. The work piece, of course, will be supported on any suitable support extending parallel to the track 6 H, II. It will be noted that the rock shaft is at about a convenient level for the work piece whereby the grinding wheel can be tilted without any corresponding up or down movement.

When the operator draws the lever 2: towards him the rocker or pendulum 6i swings to the right, Figure 3, and when he pushes the lever 52 away from him the rocker or pendulum 6'! swings to the left, Figure 3. When the operator draws the hand lever 53 towards him, the grinding wheel '15 rises and when he pushes the lever 55 away from him the grinding wheel i5 descends. When the grinding wheel contacts the work piece it presses against it with a force governed by the setting of the relief valve is. This relief valve can have a hand wheel, lever or knob to set the pressure since adjustable relief valves are well known. However it will be noted that the weight of the motor 86, the wei "it of the depending lever H and most of the wei it of the overhead lever are added to the find pressure force. When the operator draws the hand lever 5 towards hiin the grinding wheel '55 moves forward and when he pushes the hand lever 54 away from him the grinding wheel "it moves toward the rear of the machine. These statements are made on the basis of the connections as shown but it will readily be understood that the connections can be reversed wherever and whenever desired and that includes the piping 56 and El to operate the motor H9.

The valve pistons 2'? are normally maintained in neutral position by means of a device well known for such purpose consisting of a pair of washers 89 and till with an interposed spring 5&2, the assembly being held on a reduced end portion of the piston 2? by a nut M33 and the washer therefore contacting a shoulder of the piston 2?. The Washer 98:"? cannot rise above the position shown in Figure 4- on account of a shoulder in the casing 25 while the wash r ifil cannot descend below the position shown in Figure l by reason of a shoulder in a cap It will be seen whenever a valve piston is in the neutral or central position as shown in Figure 4, the fluid is locked in the cylinder or cylinders operated by the valve or, in case of the motor it, no fluid will flow through the motor. This feature is of importance especially in the case of the cylinders 53 because when the operator releases the hand lever .22 the inverted pendulum ii'i is held wherever he has put it. It is of importance also in the case of the cylinder 525 because the fluid locked in this cylinder holds the depending lever ll against the thrust of the grinding wheel. By means of the hand lever 53 controlling the cylinder Hi5 the opera-tor can cause the grindin wheel is to press against the work piece with the combined forces due to the pull of gravity on the overhead masses and the fluid pressure, or he can hold the grinding wheel at a fixed level by releasing the hand lever 53. Furthermore since there is a slight arcuate motion to the grinding wheel produced by operation of the cylinder iZi, the operator can use this arcuate motion as a fine downfeed.

It may be desired for some operations to allow the overhead weights to give the grinding pressure and to provide power means merely to lift the grinding wheel at will. In this aspect of the invention the pins lid and Hi; can be connected by power mechanism which will pull but not push as for instance by substituting a chain for the integral shaft i l i. This modification is illustrated in Figure 6 in which the chain is numbered 190. A further modification is illustrated in Fig'- ure 7 in which the head H and the pin H4 are connected by a spring ISI. This modification has the following advantage: if the grinding wheel 15 is on the work piece and the operator works the hand lever 53 so that the spring I9] is relaxed, the grinding pressure equals the pull of gravity on the entire mass carried by the overhead lever 10 with, of course, due allowance for masses to the right of the pin 69. Now if the operator moves the lever 53 to admit a little fluid through the hose [53 to shorten the connection, the spring 19! will be flexed somewhat thus creating a force which is subtracted from the total gravitational force thus diminishing somewhat the pressure between the grinding wheel and the work piece and the operator can continue to diminish this force until it reaches zero and eventually the grinding wheel is raised. Thus, in the embodiment of Figure 7, the operator can adjust the grinding pressure and this is a considerable advantage for lots of snagging operations.

It will thus be seen that there has been provided by this invention snagging grinders in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. A snagging grinder comprising a rock shaft, an inverted pendulum mounted on said rock shaft, an overhead lever articulated to said inverted pendulum at a point well above said rock shaft said overhead lever extending in a horizontal direction well away from said inverted pendulum, a depending lever articulated to said overhead lever at a point well removed from the point of articulation of said overhead lever in said horizontal direction, a grinding wheel shaft mounted in said depending lever at a point well below its articulation to said overhead lever, whereby a grinding wheel on said shaft can be tilted by moving said inverted pendulum, said grinding wheel can be raised or lowered by moving said overhead lever and said grinding wheel can be moved forwardly and rearwardly by moving said dependin lever, power means to move said overhead lever to raise the grinding wheel, and power means to move and to hold said depending lever.

2. A snagging grinder according to claim 1 in which the power means to move the overhead lever is also adapted to move it to press the grinding wheel downwardly and to hold it at any position in which it is put.

3. A snagging grinder comprising a car, power means to move said car, an inverted pendulum mounted on said car, power means to move and to hold said inverted pendulum, an overhead lever articulated to said inverted pendulum at a point well above said car said overhead lever extending in a horizontal direction well away from said inverted pendulum, a depending lever articulated to said overhead lever at a point well removed from the point of articulation of said overhead lever in said horizontal direction, a grinding wheel shaft mounted in said depending lever at a point well below its articulation to said overhead lever, power means to move and to hold said inverted pendulum, power means to move said overhead lever to raise the grinding wheel shaft, and power means to move and to hold said depending lever.

4. A snagging grinder as claimed in claim 3 in which said power means to move said overhead lever is also adapted to move it to press downwardly the grinding wheel shaft and to hold said overhead lever at any position in which it is put.

5. A snagging grinder as claimed in claim 4 having a motor mounted on said depending lever at a position remote from said grinding wheel shaft, a pulley on said motor, a pulley on said wheel shaft mounted in said depending lever at a pulleys.

6. A snagging grinder as claimed in claim 3 having a motor mounted on said depending lever at a position remote from said grinding wheel shaft, a pulley on said motor, a pulley on said grinding wheel shaft and a belt connecting said pulleys.

7. A snagging grinder as claimed in claim 1 having power means to move and to hold said inverted pendulum, and having spring means coupled to the power means to move said overhead lever to raise the grinding wheel whereby the weight of the depending lever can be counteracted to a varying amount by the power means and the spring means to produce varying grinding pressures.

8. A snagging grinder as claimed in claim '7 having a motor mounted on said depending lever at a position remote from said grinding wheel shaft, a pulley on said motor, a pulley on said grinding wheel shaft, and a belt connecting said pulleys, whereby the Weight of the motor is added to that of the depending lever to produce grinding pressure and the grinding pressure can be counter-acted to a varying amount by the power means and the spring means to produce varying grinding pressures.

GEORGE E. COMSTOCK 31).

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,308,933 Cavicchi July 8, 1919 2,073,400 Cumming Mar. 9, 1937 2,137,140 Lewis Nov. 15, 1938 2,308,843 Wilson Jan. 19, 1943 2,559,295 Grossenbacher July 3, 1951 2,569,291 Davis 1 Sept. 25, 1951

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