US2354509A - Abrasive cutoff machine - Google Patents

Description

July 25, 1944. s. c. DREI-1ER 2,354,509

ABRASIVE CUT-FF MACHINE Filed Nov. 25, 1942 2 Shee`ts-Sheet 1 STANLEY C. DREHER- July 25,1944. s. c. DREHER 2,354,509

ABRAS IVE CUT -OFF MACHINE Filed Nov. 25. 1942 2 Sheets-Sheet 2 Patented July 25, 1944 ABRASIVE CUTOFF MACHINE Stanley C. Dreher, Cincinnati, Ohio, assignor to The Minute-Man Machine Co.,

Cincinnati,

Ohio, a corporation of Ohio Application November 25, 1942, Serial No. 466,873

(ci. 519s) Claims.

My invention relates to abrasive cut-off machines wherein the structural material being cut is held in position on a work table by means of a clamp, while a revolving abrasive cutting wheel is brought down onto the material so as to cut it. Upon the work table, there is preferably some gauging means so that the length of the portion to be cut off may be readily predetermined.

It is an object of my invention to provide, in an abrasive cut-ofi machine of the above type, a. fluid-actuated clamping means and a. fluid-actuated cut-oiI-disk feeding means which will preclude the vnecessity of the operator manually holding the work while it is being cut or manually feeding the cutting disk to the work.

It is a further object of my invention to provide a huid-actuated arrangemet such that by the turning of a single valve, the work will be first clamped onto the work table in its predetermined position, before the abrasive cut-oi disk comes in contact with the work, thus insuring that the work is tightly held in position before and at all times during the cutting operation.

It is a further object of my invention to provide, with the above described mechanism, a work gauge which cornes in contact with the work when it is positioned on the table, but is out of contact and away from the work while it is being cut, thus preventing any cramping of the work due to the expansion of the material while being cut, and the possible breakage of the cut oiI disk.

It is also an object of my invention to provide an abrasive cut-off machine having all of the above advantages, and which may be manufactured at a relatively low cost, and which may be operated speedily and satisfactorily at a minimum of expense.

These and other objects of my invention, which will be set forth hereinafter or will be apparent to one skilled in the art upon reading these speclncations, I accomplish by that certain construction and arrangement of parts of which I shall now describe an exemplary embodiment. Reference is made to the drawings which form a part hereof and in which:

Figure 1 is a plan view of my novel cut-off machine.

Figure 2 is a front elevation of my novel cutofI machine with portions broken away.

Figure 3 is a side elevation of my novel cut-off machine.

Figure 4 is a cross-section of the cylinder and piston of the work clamp taken on the section line 4-4 of Figure 2. A

Figure 5 is a cross-,section ofthe actuating valve taken on the section line 5-5 of Figure 2.

Figure 6 is a cross-section of the actuating valve shown in Figure 5, but in its actuating position.

Figure 7 is a plan view, with portions broken away, of one form of abutment gauge.

Figure 8 is a plan view of another embodiment of my machine.

Figure 9 is a perspective view of portions of a movable gauging device included in the machine of Figure 8.

Figure 10 is a perspective view of a lever arrangement whereby my work-clamping means can be varied as tov position.

Figure 11 is a view of clamping means showing the abutment means in cross-section.

Figure 12 is a sectional view taken along the line I2l2 of Figure 8 and showing means for the adjustment of the positionof the abutment means. Y

Figure 13 is a partial plan view showing another form of gauging means.

Briefly, in the practice of my invention, I provide a work table or work support l, upon which is pivoted an arm 2, intermediate its length. The pivot point 3 is substantially at the rear edge of the table l, so the arm can swing in a vertical plane. Upon the end of the arm 2, overhanging the table, I journal an abrasive cut-oil disk 4 of the usual type. Upon the arm 2, I also mount a motor 5, which is connected to'the disk 4 for driving it. The drive may comprise a belted connection between sheaves on the motor shaft and on the disk shaft as shown. The motor 5 is preferably positioned on the arm 2, beyond the pivot point 3 so as to act as a counterbalance, slightlyv` overbalancing the arm 2 on its pivot3 so as to tend to raise the cutting disk. There is a spring 6 connecting the arm end 2 to a support 1, fastened to the frame of the machine. The spring 6 is preferably a coil spring, and is so arranged as to hold the end of the arm 2 carrying the disk 4 in its upper and non-cutting position. Suitable power connections are,- of course, made to the motor.

At the rear or back en d of the arm 2, I provide fluid pressure operating means. In the form shown, a piston 8 has its rod 9 connected to the arm. The cylinder ill, in which the piston operates, is pivoted to a support l2 on the frame oi the machine. Connected to the closed end of the cylinder I0, is a iiuid pressure line I3, connected through a valve I4 to a source of fluid under pressure. While I preferably use compressed air as my pressure fluid, it is to be understood that any other gas or a liquid may be used to accomplish my purpose.

From the above, it is apparent that upon applying uid pressure to the cylinder I through the line I3, the piston 8 will be forced upwardly, and the disk 4 will be moved toward the table I and into cutting operation, and through the desired cutting stroke.KV Upon relief of the pressure in the line I3 and the cylinder l0, the pull of the spring 6 will lift the arm and move the disk 4 away from the table I and out of ycutting position. In order to control the speed of the movement of the disk 4 from and to cutting position, I provide a dashpot which comprises the cylinder I5 enclosing the piston I6, the rod I1 of winch is connected by a link |48 to the rear end of the arm 2. The cylinder I5 is xedly mounted on a suitable support'and is closed at both ends, the piston rod passing through a suitable packing gland. A bypass pressure line I9, containing an adjustable needle valve 20, connects the ends of the cylinder so that the adjustment of the aperture-of the valve 20 will control the flow of liquid in both directions, determining the speed of movement ofthe piston I1, and hence, of the disk 4.

On the table I, I also provide a work clamp, comprising an abutment plate 2l which is preferably pivoted, as at'22, to the table I for horizontal arcuate movenent, to enable the work to be cut at any angle desired. There may be an arcuate slot 23 in the table top I, and the abutment 2| carries a bolt which rides in the slot 23 and which may be locked in a desired position, by means of a. wing nutr23a., so that the angle of the work to the plane of the cutting disk 4 can be adjusted.

I provide a clamp bracket 24, which is preferably mounted un a squared shaft 25 upon the back of the abutment 2|. There is a set screw 25a which may be manipulated to adjust the position of the bracket 24 along the abutment 2|.

Fastened to the bracket 24, is a cylinder 26, which may be parallel to the main arm of the bracket 24. The cylinder 26 contains a piston 21 which is resiliently urged -by means of a spring 28 towards the closed end of the cylinder 26. A piston rod 29 runs from the piston 21 out the end of the cylinder 26, and upon the end of this rodLI provide a clamping member 30. The shape of this clamping member will be one appropriate to the shape of the material being cut. An angular shape, as shown, is satisfactory when cutting round stock. 'I'he piston rod 29 may be keyed where it passes through the cylinder end to preventrotation.

A pressure line 3Ia is connected to the end of the cylinder 26 behind the piston 21. It is apparent that when fluid pressure is placed on the line 3Ia, the piston 21 will be forced downwardly, and the abutment 30 will be urged toward the abutment 2|, thus clamping any work placed against the abutment 2l. It is also apparent that when pressure is relieved on the line 3Ia, the spring 28 will urge the piston 21 towards the closed end of the cylinder 26 which, in turn, will move the abutment 30 away from the abutment 2I and release the work on the table. In the embcdiment of Figure 4, the cylinder 26 is held to the bracket 24 by bolt means 3Ia passing through a slot 32 in the bracket. This permits adjustment to bring the clamping means 30 in line with the center of work being clamped.

The pressure line I3 connected to the disk-feed cylinder, and the pressure line 3Ia connected to the clamp-feed cylinder, are connected together and branch into a common pressure line 34 (Figure 3). Such portions of these lines as require flexibility, may be of rubber or other flexible tubing. The remainder may be of metal piping. 'I'he common pressure line 34 is connected through the valve I4 to any suitable source of uii under pressure, as by line 35. 'I'he valve I4, as shown in Figures 5 and 6, comprises a valve plug 36 in a housing 31. The plug has a continuous channel 38 and a connecting channel 39. Figure 6 shows the valve plug turned so that pressure from the source will flow through the valve and out into the pressure line 34 and the connecting lines I3 andIa, and thus actuate both the disk-feeding piston and the work-clamp piston. When the valve plug 36 is turned (by a convenient handle for the purpose, such as shown at 40), to the position shown in Figure 5, the channel 39 of the plug connects with the line 34, while one end of the channel 38a connects with a vent orifice 4I, or a vent conduit, exhausting the pressure line 34, and permitting the disk-actuating piston and the clamp-actuating piston to return in their cylinders by reason of their respective springs.

In order to insure the clamping of the work prior to the action of the abrasive cut-off disk thereon, I make the diameter of the piston 21 of the work clamp less than the diameter of the disk-actuating piston 8. While I preferably insure the actuation of the work clamp rst by these differences in diameter of the respective pistons, it may also be desirable, and is within the province of my invention, to bring about this result -by other means, such as the overloading of the disk-actuating piston relative 4to the load of the work-clamping piston. In constructing my device, and depending upon the different resistances to the two pistons, and depending ,upon their relative surface areas, it may be that the work-actuating clamp will be completely'actuated before any movement at all of the cut-olf disk-actuating piston, or on the other hand, it may be that the cut-off disk-actuating piston will move to a slight extent before the work clamp actuating piston has completed its full stroke. In any event; within the contemplation of my invention, it is only necessary that the work be fully and substantially clamped prior to the contact of the periphery vof the cut-off disk 4 with the work.

In connection with my novel cut-off machine, I provide an abutment gauge, one form of which is shown in Figure 7. This gauge comprises a sleeve 42 having graduations thereon, as shown at 43. The sleeve is slidably mounted in a bracket 44 which is permanently fastened to the table I. I provide a thumb screw 45 which maintains the position of the sleeve 40 within the bracket. There is a rod 46 running through the sleeve 40 with each end projecting. Upon one end, I provide an abutment or gauging arm 41, which is at right angles to the rod 46. At the other end, and fastened thereto. I provide a knob 48. There is a. coil spring 49 which connects the rod 46, through the knob 48, to the sleeve 32. The spring 49 is so coiled that it maintains the gauging arm 41 to one side of the sleeve 48. However, when the knob 48 is manually turned, the gauging arm 41 may be positioned on the other side of the sleeve 40. The sleeve 42 is so mounted upon the table, that the gauging arm 41 is only within the path of the work when the knob 48 is manually turned as described, but when the knob 4I is released, the arm springs back out of the way of the work.

The abutting gauge is manipulated and adiusted by sliding the sleeve 42 in the bracket 44 5 ered and the weight of the arm i2 will cause the l until the predetermined indicia 4I registers with the edge ofthe bracket 44. Then the thumb y screw 4I is tightened, thus maintaining the position of the sleeve 42. The work is then placed on the table against the abutment 2l, the work- 10 man holding the work with one hand while he turns the knob 48 on the gauge with the-other. Thus, the gauging arm 41 comes into position in line with the work. The work is then slid up until it abuts against the arm 41. Thereupon, 15

theknob 4l is released, and the gauging arm 41 moves away from the work. The purpose of removing the gauging arm 41 from contact with the end of the work, is to prevent cramping the work during its cutting, by reason of the expanf 20 sion of the work due to the heat occasioned by the cutting disk.

The complete operation of the machine is as follows. The work is gauged, as described above,

and after the knob 48 of the gauge is released, 25

the valve plug 36 is turned from the position in Figure 5 to the position in Figure 6, by means of the handle 40. This permits the fluid under pressure to ilow through the pressure line I4 and the pressure lines and Il. Inasmuch as the cylinder and piston, 29 and 21, are of a smaller diameter than the cylinder and piston,v I and l, the work clamp abutment 2l will quickly travel down and clamp the work against the abutment 2l. Thereafter, 35

the piston l will bring the cut-olf disk 4 down onto and through the work. After the piece has been cut, the valve plug I6 is movedvto the position shown in Figure 5. This relieves the pressure on the pressure lines, and the work' clamp'y abutment 30 moves away from the work due to the spring 2B, while the disk 4 movesupwardly due to the combined weight of the motor l and the pull of the spring l. The dashpot I controls the return movement las to speed, while it also controls the advance movement or feeding movement of the disk 4.

In the provision of gauging means, it is frequently advantageous to have them automatic' Sla and I3 to the cylinders 26 30 4o of the cylinder.

shaft 53 to rotate in a counterclockwise direction, as shown in Figure 9. This will bring the arm to such a position as that shown in dotted lines, wholly below the plane of the work. Instead of relying on weight actuation, I may, of course, v

employ springs or other resilient means to draw the arm 52 downwardly when it is not pulled up by the rod I8.

In order to provide support for the work piece during gauging and before it is severed, I may employ one or more brackets, 60. As a matter of convenience, these brackets or supporting bars may be slidably mounted on the conduit 34 which. in this embodiment, runs along the frontedge of the table I. The bracket or brackets III, after they have passed the forward edge of the hole Il in the table top, are offset downwardly so as to lie in the plane of the table top. Thusthey support the work piece during the gauging operation, but may be so positioned as not to interfere with the depositing of the severed portion of the work piece onto the chute 5I.

Yet another form of gauge is illustrated in Figure 13, where the actual gauging abutment ll, operating across the perforation in the table top, is-fastened to the piston rod 62 of a fluid pressure cylinder 62. This cylinder may be slidably mounted as by means of a collar 64 on the con-A duit 34, and the external surface of the conduit may .be provided with graduations or indicia to aid in the positioning of the gauging abutment. The cylinder 63 contains a compression spring 6l bearing against the piston, while-the piston rod 62 passes through a gland at 'theforward end To this end of the cylinder, I make a fluid connection, as at 66, which may be connected by a-ilexible conduit 61 to the line 34, or to any pointl in the pressure system beyond the valve or valves which are employed. Normally 'lying within the plane rand` across the position of the work piece, the abutment 6I will thus be withdrawn from that position sohas to clear the Work as shown in dotted lines. in Figure 13, when fluid pressure is applied to the cylinder 62, and the application of this fluid pressure can in opera'tmn so as to require no movement'son 50 thus be caused to be automatic in its occurrence.

the part of the workman. One such gaugingl devvice is shown in connection with machinev of Figure 8. Here, the table l-lof'tl'na,` .f

machine is cut away, as at 50, to form an openL ing beyond' the cut'on plane of the`abra'sive 55.plateand is slotted, as shown at Y 10. A stud or disk 4. Beneath this opening, there may be.. arranged a chute 5I to carry away the cut pieces. A gauging arm 52 (see also Figure 9), is slidably,

but non-rotatably, xed to a shaft I Lwhich, in turn, is pivoted beneath the table I'fin. brackets@ I provide a means whereby a gauging abutment 52 may be moved down out of the plane of the work piece substantially at the start of the actual cutting operation. To this end, I provide another arm 51 on the shaft El, which may be conbolt, 1I, passes through the slot in the arm and is fixed to the table top. The abutment means 2 I, instead of being pivoted directly-to the table top, as in the machine of Figure 1, is in this instance pivoted to the plate 68, as at 12. At its other end, the plate is fastened to the carriage means 12, slidably mounted on a trackway 14 fastened to the edge' of the table top. The position of the 5 carriage along the trackway may be fixed by means of a thumb screw 15 threaded into the gauge and engaging the trackway. Thus, the plate 88. carrying with ittheabutment 2l, `can Ibe moved transversely to the table top when the bolt 15 is loosened, the carriage 13 sliding on the track 14, and the slotted arm 69 sliding on the bolt or stud 1 I. l

To facilitate the movement of the plate 6l, as

described, I pivot a shaft 16 in brackets" and 18 nected by a link or rod 58 to a pivotal stud or 75 beneath the table top. Non-rotatably affixed to the shaft 16, are arms 19 and 80, extending generally upwardly. Each of these arms is slotted at its free end, as shown in Figure 10. The arm 19, by means of its slot, engages a pin or the like,

. 8|, on the plate 68, while the arm 88 engages a stud 82 on the carriage 13. The arm 19, of course, operates through a suitable slot or perforation in the table top. The lever 88 is also non-rotatably fixed to the shaft 16 and extends forwardly beneath the table top to a position of access to the operator. By means of this lever, the operator can thus move the plate 68 and attendant parts toward or away from the front edge of the table. When the desired position is reached, the plate may .be xed in that position by means of the bolt 15.

The abutment member 2| may -be provided with a quadrant 84 having an arcuate slot 85, curvature of the slot being such that its center is at 12. A boit or studss is amxed to the pme sa and extends through the slot 85. It may be provided with a lock nut (not shown) as will be readily understood. The quadrant 84 may also be provided with indicia or graduations, as Shown.

In Figure 11, I have shown a modified mounting of the cylinder 26 on the bracket 24. The bracket is still slotted, as at 82, and a stud-like element 81 is thus adjustable along the slot. But this element is connected to the cylinder and through a pivot joint 88, which comprises two radially scored members positioned lin face-toface relationship, and held by a bolt or the like, 89. 'I'his permits the angularity of the-cylinder to be adjusted lwith reference to the substantially vertical arm of the bracket 24.

While I have shown, in Figures 3, 5 and 6, a single valve controlling the application of fluid under pressure to the various cylinders-where the conduit 34 passes along the front edge of the table, as in the machine of Figure 8, two or more valves may be employed. Here I have shown a valve 88 having a handle 9| and controlling the application of-uid under pressure to the cylinder I9. 'I'his valve may be a one-way valve. I have shown another valve, 92, connected in series with the valve 90. This valve is a two-Way valve and controls theapplication of iiuid under pressure not only to the line 34, but also to the line`8 la, which controls the clamping cylinder 26. 'I'he operating arm 93 of valve 92 may be connected to the handle 9| by a pivoted link 94. .'B`y proportioning the parts, it can be made certain in this structure that the clamping action of cylinder 26 is completed, if desired, prior to the down swing of the arm 2, as produced by the cylinder I0. A guard 85 may be provided for the cutting disk, as shown best in Figures 2 and 3. This guard may be pivoted, as at 96, to brackets on the front edge of the table top so that it may be swung out of position when it is necessary to change disks.

Modifications may be made in my invention without departing from the spirit of it. Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a machine of the class described including a table, a work gauge comprising an abutment, a. bracket on said abutment, a fluid pressure cylinder on said bracket, and a clamping means actuated by said fluid pressure cylinder and acting to clamp work against said table and said abutment, said abutment being movable with respect to said table whereby said bracket and hydraulic clamping means is movable with said abutment to selected positions on said table. 1

2. In a machine of the class described including a table. a work gauge comprising an abutment, a bracket on' said abutment, a uid pressure cylinder on said bracket, and a clamping means actuated by said iluid pressure cylinder and acting to clamp work against said table and said abutment, said abutment being movable with respect to said table whereby said bracket and hydraulic clamping means is movable with said abutment to selected positions on said table, and means for adjusting the position of said cylinder with respect to said bracket. l

3. In a machine of the class described including a table, a work gauge comprising an abutment, a bracket on said abutment, a iiuid pressure cylinder on said bracket, and a clamping means actuated by said uid pressure cylinder and acting to clamp work against said table and said abutment, said abutment being movable with respect to said table whereby said bracket and hydraulic clamping means is movable with said abutment to selected positions on said table, and means for adjusting the position of said cylinder with respect to said bracket, both -as to the position of attachment of said cylinder and its angular relation to said abutment. Y

4. In a machine of the class described a table, an arm pivoted on said table, a cutting disk journaled on said arm, a motor on said arm, and a drive between said motor and said cutting disk, :duid pressure means for moving said arm, an abutment on saidl table, uid pressure means for clamping Work against said table and said abutment, and means for applying iiuid pressure to said fluid pressure means in such manner that work can be clamped prior to the feeding of the disk thereagainst, said abutment means being pivoted 'on said table and bearing said clamping means whereby said clamping means are effective irrespective of the position o1' said abutment means.

5. In a machine of the class described a table, an arm pivoted on said table, a cutting disk jour- Analed on said arm, a motor on said arm, and a drivebetween said motor and said cutting disk. fluid pressure means for moving said arm, an abutment on said table, fluid pressure means for clamping work against said table and said abutment, and means for applying fluid pressure to said fluid pressure means in such manner that work can be clamped prior to the feeding of the disk thereagainst, said abutment means being pivoted to a plate, said plate being slidably mounted with respect to said table, said abutment bearing said clamping means, and said plate having means for adjustably fixing it in a plurality of positions on said table. i

6. In a machine of the class described a table, an arm pivoted on said table, a cutting disk journaled on said arm, a motor on said arm, and a drive between said motor and said cutting disk, fluid pressure means for moving said arm. an abutment on said table, fluid pressure means for clamping work against said table and said abutment, and means for applying fluid pressure to said iiuid pressure means in such manner that work can b e clamped prior to the feeding of the disk thereagainst, said abutment means being pivoted to a plate, said plate being slidably mounted with respect to said table, said abutment bearing said clampingmeans, and said plate having means for adjustably xing it in a plurality on said table, said table opposite the part thereof bearing said plate being cut away and provided with a chute beneath to receive cut work pieces, a gauge for gauging the length nf work pieces, and means for moving said gauge out of contact with work pieces prior to the severing thereof.

7. In a machine of the class described a table, an arm pivoted on said table, a cutting disk journaled on said arm, a motor on said arm, and a drive between said motor and said cutting disk, fluid pressure means for moving said arm, an abutment on said table, uid pressure means for clamping work against said table and said abutment, and means for applying uid pressure to said fluid pressure means in such manner that work can be clamped prior to the feeding of the disk thereagainst,V said abutment means being pivoted to a plate, said plate being slidably mounted with respect to said table, said abutment bearing said clamping means, and said plate having means for adjustably fixing it in a plurality of positions on said said table, said table opposite the part thereof bearing said plate being cut away and provided with a chute beneath to receive cut Work pieces, a gauge for gauging the length of work pieces, and means for moving said gauge out of contact with work pieces prior to the severing thereof, and means extending across the perforation in said table for affording partial support to a work piece during cutting but so positioned as to permit gravity delivery of a cut portion of a work piece to said chute.

8. The structure claimed in claim '7 wherein said plate is slidable in a fixed direction on ways provided in connection with said table, and including locking means for said plate, and means including a lever operable from the front of said table for moving said plate when unlocked.

9. The structure claimed in claim 7 wherein said plate is slidable in a xed direction on ways provided in connection with said table, and including locking means for said plate, and means including a lever operable from the front of said table for moving said plate when unlocked, and in which locking means is provided for said abutment means whereby it can be locked in selected angular positions on said plate.

l0. In a machine of the character described, a table, a cutting disk including a drive therefor. feed means for said cutting disk, work clamping means in connection with said table and gauging means in connection -with said table, and means for actuating said clamping means, said feed and said gauge means to move it from the path of said work, and a single control means for said actuating means whereby after the presentation of Work to the machine and against said gauging means the said work will be clamped, the gauge moved out of the way and the said work cut as a series of automatically occurring successive operations.

STANLEY C. DREI-IER.

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