US2251607A - Abrading machine - Google Patents

Description

Aug, 1941? c.-J. AsTRowsKl ETAL 2,251,607

\ ABRADING MACHINE Frank J. Fritz by JV 17 Ther" Attorney.

2 Sheets-Sheet 2 Inventors: Charles J. vovvsk= v FTaTwK J. Frtz,

Aug.5, 1941. c. J. AsTRowsKl Erm.

ABRADING MACHINE Filed June 28, 1959 Figi).

. narrow tolerances.

Patented Aug. 5, 1.941

UNITED STATES PATENT OFFICE ABRADING MACHINE Charles J. Astrowski and Frank J. Fritz, Schenectady, N. Y., assixnors to General Electric Company, a corporation of New York Application June 2s. 1939, serial No. 281,543

s claim. (ci. n n) A surface to be ground or honed within extremely' narrow limits of accuracy and for stopping the abradlng operation immediatelyrupon the finishlng of the surface to the desired dimension.

Another object of our invention is to provide an abrading machine including an improved ar'- rangement for coordinating automatically the positioning and operation of the abrading vtool and for automatically gauging the surface to be nishedto provide accurate and consistent iinishlngvof the surface of the work within very Further objects and advantages of our invention will become apparent as the following description proceeds, and the features of novelty which characterize our invention will be pointed out with particularity in the claims annexed to y and forming a-part of this specification.

For a better understanding of our invention, reference maybe had to the accompanying drawings in which in section of an automatic cylinder honing'machine embodying our invention: Fig. 2 is an enlarged detail view, partially in section, of the spindle of the machine shown in Fig. 1; Fig. 3 is a side elevation view showing the opposite side of the work holding support of the machine shown in Fig. 1,; and Fig. 4 is an enlarged view of a portion of the machine shown in Fig. 1 on the line 4-4 thereof.

In the illustrated embodiment of our invention, we have shown a honing machine'of the Fig. 1 is a side elevation view partly type utilizing a hone having expansible elements or abrading sticks and provided with a spindle j whereby the hone may be rotated and reciprocated with respect to the work. lTherotation or reciprocatimrzof the hone or abrading tool is effected lby operation of a motor and suitable shafts and 'levers and the movementof the abrading tool toward and away from the work as well as the expansion and contraction of the abrad= lng elements thereof is effected by a fluid pressure operated mechanism. The operation of the mechanism vto perform the several functions thereof is coordinated and the fluid pressure is controlled in such a manner that the finishing I of the honed surface may be effected consistently within extremely narrow limits of accuracy, a suitable 'gauging mechanism being provided to terminate the honing operation when the surface of the work has been finished to the required size. The honing machine illustrated is particularly adapted for high speed production of compressor cylinders and will accurately finish large numbers of such cylinders without requiringfmanual gauging of the cylinders during the honing operation or any adjustment by the operatorduring the operation on-'fa givenl piece of work', it being necessary merely to place the work in positionon the machiney'start the machine and remove the work after the machine has stopped automatically. y

Referring now to 4the drawings, in "Fig. 1 we haveshown a honing machine for honing thebores of refrigerant compressor cylinders and comprising a support or standard II) mounted on a base I'I and provided with a work support I2 and a spindle I3. The'spindle I3 is arranged to be rotated and reciprocated by operation of an electric motor Il which actuates a rocking crank I5 through a worm I6 and gear I1, crank 'I5 being slidably connected to a collar I8 mounted on the spindle I3 and being connected to be driven by the gear I1 through a link I9 and crank 20. Extension 2Iof the motor shaft rotates the spindle through a worm (not shown) nector 30a at the upper end thereof, to which 'me lever .la is pivoted at al, the rodszs and I 30 being connected by a link 32. In Fig. 1 the spindle has been shown in its raised position. We have shown a compressor block 33 having a cylinder bore 34 lsecured in place on the work support i2, the block being held between the stationary support I2 and movable clamp 3l ar A. ranged to'be raised and'lowered by operation of the lever 38 through a rack and pinion 31, 38. suitable guides 39 being provided for the clamp. The clamp 35 is provided with a bore 43 arranged to guide the abrading tool or honing elementI into the cylinder 34 of the work. In order to control the motor I4 we provide a switch mechanism 4I provided with start and stop buttons 42 and 43 respectively, the switch mechanism being arranged to connect the motor to suitable supply lines 44.

When the spindle is lowered into its working position a lower inclined face 45 of the forked connector 30a rests on an adjustable wedge 46l to the lower end of the spindle on an extension.

49 connected to the spindle by a ball and socket joint 58 having a removable collar 5I, the tool 26 being secured in the lower end of the extension 49 by a ball and socket joint 52. The hone comprises a plurality of honing sticks or working elements 53 held in suitable shoes 54 and retained by garter springs 55 in 4suitable slots or grooves in a cylindrical frame or quill 56. Each of the shoes 54 is provided with 'a pair of lugs 51 slidably mounted in holes in the quill 56 and engaging cones 58 secured on an operating rod 59 passing through the 'center of the tool. The spindle I3 and shaft 49 are hollow and are provided with rods 68 and 6I respectively held together by a slot and key connection 62 adjacent the ball and socket joint 68, the rod 59 being secured to the lower end of the rod 6I by a slot and key connection 63 whereby longitudinal movement of the rod effects movement of the cones'58 to force the honing sticks radially outwardly. In order to effect longitudinal movement of the rod 60 within the spindle, we provide a piston 64 mounted in a cylinder 65 near the top of the spindle and provided with compressed air inlets 66 and 61 at the top and bots tom thereof to effect downward and upward movement respectively of the rod. In Fig. 2 the gear 22 for rotating the spindle has not been shown, since it would be connected in the broken away portion. The collar lowering the spindle is rotatably mounted between collars 68 and 69 which are secured to the spindle. In order to supply compressed air to the cylinder V during rotation and reciprocation of the spindle, we provide a sleeve or collar 18 having annular grooves 1I and 12 arranged to communicate with the inlets 66 and 61 respectively and connected to flexible fluid pressure conduits 13 and 14 respectively. The collar 10 is arranged to be held stationarywhile the spindle is rotated therein, suitable oil sealed packings 15 and 16 being provided near the upper and lower end respectively of the collar 10. It is, therefore, evident that the honing spindle may be rotated and reciprocated without interfering with the desired communication between the compressed air supply conduits 13 and 14 and the upper and lower ends respectively of the cylinder 65.

yIn order to determine when the work has been nnlshed to the required dimension, we provide a gauge or gauging plug 11 arranged to test the size of the work after each stroke of the honing tool. The gauge 11 is mounted on a slide 8 extending throughv the work support I2 and into I8 for raising and the base II oi the machine. A locating plug or preliminary gauge 19 having a diameter slightly smaller than that of the gauge plug 11is arranged to enter the work ahead of the plug 11 and locates the plug 11 with respect to the cylinder bore. The plugs 11 and 19 are secured to the upper end of the slide 18 b v a cap screw 80. The slide 18 is biased upwardly toward the work by a helical spring`8I. In order to prevent the tool 26 from coming in contact with the gauge plugs we provide a pin or rod 82 extending upwardly through the work support I2 and clamp 35 and provided with a wheel 83 at the top thereofarranged to engage a disk 84 rigidly secured to the spindle I3. The rod 82 is secured to the slide 18 on a collar 85 and it is readily apparent that when the spindle moves downwardly to place the tool 26 in its working position, the disk 84 will press the rod 82 downwardly and move the slide 18 away from the work 33 against the pressure of the spring 8|. The disk 84 is rotated with the spindle and the wheel 63 is provided to prevent undue friction between the rod and the disk. Also attached to the collar 85 is a guide rod 86 which extends upwardly through the base Il and the lower portionk of the work support I2 as clearly shown in Fig. 3. This rod is provided in order to move thegauge plugs out of their gauging position when the work is being adjusted on the support. An arm 81 pivoted to the support I2 at 88 is provided with a pin 69 engaging the top of the rod 86. The handle 36 for operating the clamp 35 rotates a cam 90.which engages the arm 81 vand presses the rod 86 downwardly whenever thehandle 36 is rotated to move the clamp 35 away from the work. This arrangement keeps the gauging plugs out of the way during the handling of the work.

In order to control the movement of the spindle and the abrading tool toward and away from their respective working positions, we provide a valve 9I actuated by a solenoid 92 which is energized whenever the motor I4 is connected across the power supply lines 44. The valveSI is arranged to connect the duid supply lines for thepistons 28 and 64 to a suitable source of compressed air through a supply pipe or conduit .93. As clearly shown in Fig. 1, the solenoid placed in communication with the supply conduit 93 depending upon the position of two valve pistons 98 and 99 rigidly secured to the armature 94 on a valve stem |00. In its drop out" position the solenoid valve 9| connects the outlet connection 96 to the supply conduit 93 and in its pick up position it c onnects the outlet 91 to the supply conduit. When the solenoid valve is in its drop out position the outlet 96 conveys fluid under pressure to a conduit IOI to raise the pistons 28 and 64 and thereby retract the honing sticks and move the spindle away from its working position. When the solenoid is in its pick up position a supply conduit 91 conveys uid under pressure through a supply conduit I02 to lower the spindle to its working position and to move the honing sticks radially outward into their `working positions. In order to maintain the hone or abrading tool in its retracted position when the spindle is not in its working positool from its working position.

tion, we provide within the boss 41 a pair of valves comprising vducts or ports |03 and |04' in the rod 30 arranged to provide communication between the supply conduits and |02 and the flexible conduits 14 and 13 respectively when the rd 30 is in its lowermost position. The arrangement of the valve ducts |03 Land 04 and the-passages which they connect is' clearly shown in Fig. 4. The ducts |03 and |04 are arranged on opposite sides of the axis ofthe rod 30 so that they provide communication between the supply and delivery conduits only when the rod is in its lowered position.

The arrangement of the valve ducts |03 and |04 in the rod 30 insures actuation of the mechanism in a manner such that the honing sticks cannot be forced outwardly against the work when the honing tool is being moved toward or away from its working position uponoperation oi the piston 23. In the position of the spindle shown 1n Fig. 1, the rod :n is heid in as raised sure regulating device insures a constant vpredetermined pressure between the honing sticks and sure reV lthe work and highly yconsistent work is, performed by the machine lwithout the necessity of frequent adjustments of the setting of the hone. In order to prevent the passage of foreign matter to the pressure control device |03, we provide a suitable filter or strainer |03 at the inlet side oi the prestor. As soon as the compressor -cylinder has been finishedv to the desired size, the gauge 11 will position by fluid pressure admitted to the lower side of the piston 23 through the connection 30 and the conduit |0|. In this position, the valve ports |03 and |04 are, raised and communication between the supply conduits |0| and |02 and the ilexible conduits 13y and- 14 is cut of! by the rod 30.' Although the air pressure to the lower side of the hone expanding piston 04 has been cut oil,

the hone sticks are maintained in their retracted position by the garter springs il. If the,

motor is .now startedby pressing thel starting button 42, the solenoid valve will"be"' picked up and compressed air admitted to the connection 31 and the air will enter the top side of the cylinder 21-through the conduit |02`--and force the piston 23 downwardly thereby moving the tool into its working position. When the rod reaches its lowermost position the provide communication between the conduit |02 port `|04 will and the flexible conduit. 13 thereby admitting the top side of the piston 04 66 and expanding the hone, this operation being effected while the motor is rotating and reciprocating the spindle I3. When the honing operation has been completed, switch 4| is actuated to deenergize the motor and solenoid valve and iiuid pressure is thereby cut offfrom the conduit |02 and admitted to the conduit IDI. Since the conduit |0| is in direct communication with the flexible conduit 14 through the port |03; the fiuidpressure is immediately compressed air to through the inlet effective to force the piston 64 upward and return the honing sticks to their retracted positions. Since the weight of the spindle and its associated mechanism such as the arm I5 is great as compared with that of the parts connectedto the piston 64. the piston 04 is operated immediately and moves to its upper positionbefore the iiuid pressure can raise the piston 23 sufliciently to cut 0H the port |03. It is, therefore, apparent that the honing elements are retracted before the spindle is raised to remove the abrading This arrangement prevents bell-mouthing or other injuries to the work.

In order to obtain a high degree of accuracy and consistent finishing of large numbers of pieces of work, we provide a fluid pressureregulating device |05 in the 'conduitl02 between the inlet 91 and the inlet 03 of tlie cylinder 05. The

pressure maintained by the device |00 may be `ad justed by adjustment of athumb screw or other suitable device |00. the selected position being determined by a pressure gauge |01.l The presenter the cylinder. This movement of the gauge into the cylinder 'is utilized to stop the honing operation. and thereby prevent any further honing of the cylinder bore after It has been ilnislied tothe desired size. vIn order to stop the honing machine illustrated in Fig. l, we provide a bell crank |03 having an adjustable screw ||0 arranged to engage'the stop button 43 of the .switching mechanism 4|. When the gauge plug 11 enters the cylinder bore. the rod 32 follows the disk 34 and a lug secured to the rod' strikes against the stop button 43 to stop the motor I4 and deenergize the solenoidl valve 0| thereby operating the fluid pressure pistons to retract the labrading elements and'lift the spindle away from its working position.` f v The' operation of the honing machine described above is as follows: A piece of work such as the cylinder -block 33 is placed 'omthe work support duit |02 to force the piston 23 downwardly. -The spindle I3 is thus moved into its working position with'the honing tool 26 in the cylinder bore` 34 which is to be honed. As soon as the piston 23.

reaches'its lowermost position( the port |04 in the rod -30 provides communication between the conduit |02 and the iiexible conduit 13 and there-Y by forces the 'piston 34 downwardly inthe cylinder 65 and expands the hone by moving the abrading elements 53 radially outward into their working positions; Rotation and reciprocation oi' the honing tool 20 removes material from the cylinder. walls at a rate dependent upon the pressure maintained byA the regulating device |05 in accordance with the setting of` the adjusting screw |06. On each stroke of the spindle I3 as it reaches its upper position, the gauge block 13 enters the cylinder bore, and. as soon as the bore` has been iinished to the desired size, the gauge plug 11 follows thegauge plug 13 into the bore and allows the rod 82' to move upwardly until the lug` |I| strikes the bell crank |03 thereby pressing the stop button 43 of the switching mecha# nism 4| and'deenergizing the motor andsolenoid valve. The valve thereupon falls to its drop out position admitting compressed air to the flexible conduit 14 through the conduit I|0| and port |03 and contracting the hone by raising the piston 34. Compressed airis admitted also to the lower side of the piston 20 in the cylinder 21 and the piston is raised to lift the spindle I3 away from its working position. The retraction of the honing elements from their working positions is assured before the spindle can liit the tool from its position within the finished cylinder because the spindle and the partsof the mechanisrn which move therewith have a high moment of inertia as compared with that of the piston 64 and its associated mechanism. The entire honing operation iseffected within extremely narrow tolerances in a single operation of the automatic machine. Because of the automatic gauging it is unnecessary to stop and adjust the hone or to stop the machine in order to gauge the work,

From the foregoing, it is readily apparent that we have provided a simple and effective abrading machine and control which makes possible the finishing of large numbers of pieces within extremely n-arrowlimits of accuracy. Oversized finishing of bores or other surfaces is prevented as well as defects such as bell-mouthing.

While we have shown our invention as applied to a cylinder honing machine, other applications will readily be apparent to those skilled in the art. We do not, therefore, desire our invention to be limited to the particular construction shown and described and we intend in the appended claims to cover all modifications within the spirit and scope of our invention.

What we claim as new and desire to secure by Letters Patent of the United States, is:

1. In an abrading machine, a work support, an abrading tool movable toward and away from a working position and having an abrading element movable toward and away from a working position, means for operating said tool in its working position, fluid operated means for moving said tool toward and away from its working position, fluid operated means for moving said abrading element toward and away from its working position, common fluid pressure conduit means for conveying fluid under pressure to both of said fluid operated means to effect movement of said tool and said abrading element toward their respective working positions, common fluid pressure conduit means for supplying fluid under pressure to both of said fluid operated means to effect movement of said tool and said abrading element away from their respective working positions, a common source for supplying fluid under pressure to both of said conduit means, means for selectively connecting either of said conduit means to said source, and means for assuring positioning of said second-mentioned fluid operated means to hold said abrading element away from its working position before said first-mentioned fluid operated means can effect movement of said tool into or out of its working position.

2. In an abrading machine, a work support, an abrading tool movable toward and away from a working position and having an abrading element movable toward and away from a working position, means for operating said tool in its working.

position, fluid operated means including a rod for moving said tool toward and away from its working position, fluid operated means for moving said abrading element toward and away from its working position, a common source for supplying fluid under pressure to both of said fluid operated means, and means including valves arranged to be actuated by said rod for assuring positioningV of said second-mentioned fluid operated means to hold said abrading element away from its workingV position before said first-mentioned fluid operated means can effect movement of said tool into or out of its working position.

3. In an abrading machine, a work support. a clamping device for holding the work in position means, means for assuring positioning of said second-mentioned fluid operated means to hold said abrading element away from its working position before said first-mentioned fluid operated means' can effect movement of said tool into or out of its working position, means including a gauge for determining when the-work has been finished to the desired size and for terminating operation of said machine, and common means for moving said clamping device to and from its clamping position and for moving said gauge to and from its gauging position.

4. In an abrading machine, a work support, an abrading tool-movable toward and away from a working position and having an abrading element mov-able toward and away from a working position, means including a motor for rotating said tool and for reciprocating said tool with respect to said support. fluid operated means for moving said tool toward and away from its working posil' tion, fluid operated means for moving said abrading element toward and away from its working position, common fluid pressure conduit means for conveying fluid under pressure to both of said fluid operated means to effect movement of said tool and said abrading element toward their respective working positions, common fluid pressure conduit means for conveying fluid under pressure to both of said fluid operated means to effect movement of said tool and said abrading element away from their respective working positions, means for supplying fluid under pressure to both of said conduit means, means including a solenoid operated valve for selectively connecting either of said conduit means to said fluid supplying means, said solenoid valve being arranged when deenergized to connect said fluid supplying means to said second-mentioned fluid pressure conduit means, means including a gauge arranged to move over the surface of the work when the work has been finished to the desired size, a common electrical circuit for energizing said solenoid and said motor, and means including a switch arranged to be actuated by movement of said gauge over the surface of the work for deenergizing said circuit to stop said motor and to withdraw said tool from its working position.

5. In an abrading machine, a work support, an abrading tool movable toward and away from a working position and having an abrading element movable toward and away from a working position, means including a motor for rotating said tool and for reciprocating said tool with respect to said support, fluid operated means for moving said tool toward and away from its working position, fluid operated means for moving said abrading element toward and away from' its working position, common fluid pressure conduit means for conveying fluid under pressure to both of said fluid operated means .to effect movement of said tool and said abrading element toward their respective working positions, common fluid pressure conduit means for conveying fluid under pressure to both of said fluid operated means to effect movement of said tool andv said means including a solenoid operated valve for selectively connecting either of said conduit means to said uid supplying means, said solenoid valve being arranged when deenergized to connect said iiuid supplying means to said second-mentioned fluid pressure conduit means, said first-mentioned fluid operated means and the mechanism associated therewith having a greater moment of inertia than said second-mentioned fluid operated means and the mechanism associated therewith whereby fluid pressure supplied to said secondmentioned fluid pressure conduit means effects operation of said second-mentioned `fluid operated means before effecting operation of said first-mentioned iluid operated means.

6. In an abrading machine, a work support, an abrading tool movable toward and away from a working position and having an abrading element movable toward and away from a working position, means for operating saidtool in its working position, fluid operated means including a rod and a rod guide for moving said tool toward and away from its working position, fluid operated means for moving said abrading element toward and away from its working position, a common source for supplying vfluid under pressure to both of said fluid operated means, and means including valves formed in said rod and said rod guide for assur- 'ing positioning of said second mentioned iluid operated means to hold said abrading element away from its working position'before said rst mentioned uid operated means can eiect movement of said tool into or out of its working position.

7. In an abrading machine, a work support, an abrading tool movable toward and away from a working position and having an abrading element movable toward and away from a working position, means for operating said tool in its Working position, fluid operated means including a rod and a rod guide for moving said tol toward and away from its working position, fluid operated means for moving said abrading element toward and away from its working position, a common source for supplying fluid under pressure to both of said uid operated means, valve means selectively operable into either of two positions for controlling the operation of said machine, said valve means in one position connecting said source to both of said iiuid operated means to effect movement'of said tool and said abrading element into their working positions and in its other position connecting said source to both of said fluid operated means to eiect movement of said tool and said abrading element away from their working positions, and means including valves formed in said rod and said rod guide for assuring positioning of said second mentioned iluid opi erated means to hold said abrading element away .Y lfrom its working position before said first mentioned iiuid operated means can eiect movement of said tool into or out of its working position.

8. In an abrading machine, a work support, an abrading tool movable toward and away from a Working position and having an abrading element movablevtoward and away from a working position, means for operating said tool in its working position, uidroperated means for moving said tool toward and away from its working position, fluid operated means for moving said abrading element toward and away from its working position, a common source for supplying fluid under pressure to both of said uid operated means, valve means selectively operable into either of two positions for controlling the operation of said machine, said valve" means in one position connecting said source to both of' said fluid operated means to effect movement of said tool and said abrading element into their workingposltions and in its other position` connecting said source to both of said fluid operated means to effect movement of said tool and said abrading element away from their working positions, electrical means for actuating simultaneously said valve means and,

said means for operating said tool, .and iluid pressure regulating means arranged between said source and said second mentioned iiuid operated means for controlling the pressure between said abrading element and the work.

CHARLES J. ASTROWSKI. FRANK J. FRITZ.

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