US1918198A - Gauging mechanism for internal grinders - Google Patents

Description

y 1933. H. v. TORNLEBQHM 1,918,198

GAUGING MECHANISM FOR INTERNAL GRINDERS Filed Oct. '17, 1951 4 Sheets-Sheet 1 INVENTOR ATTORNEY y 3: H. v. TORNEBOHM 1,918,198

GAUGING MECHANISM FOR INTERNAL GRINDERS Filed Oct. 17, 1931 4 Sheets-Sheet 2 INVENTOR ATTORNEY July 11, 1933. H. v. TURNEBOHM GAUGING MECHANISM FOR INTERNAL GRINDERS 4 Sheets-Sheet 3 Filed 001;. 17, 1931 T, N w mm m WN a 4716? yd/demar 75'RNEBOHM $4 {7/ M 4; ATTORNEY y 1933- H. v. TORNEBOHM 1,918,198

GAUGING MECHANISM FOR INTERNAL GRINDERS Filed Oct. 17, 1951 4 Sheets-Sheet 4 I5 INVEI IITOR 14 41 616 Valdemar 7bR/v50//M Patented July 11, 1933 UNITED STATES PATENT OFFICE HILDING VALDEMAR TbRNEBOHM, GOT'IENBORG, SWEDEN, ASSIGNOR TO AKTIEBO- LAGET SVENSKA KULLAGERFABRIKEN, OF GOTTENBORG, SWEDEN, A CORPORA- irIoN or SWEDEN GAUGING MECHANISM FQR INTERNAL GRINDERS Application filed October 17, 1931. Serial No. 569,385.

. Thisinvention relates to a mechanism for automatically gauging the progress of the work in bore grinding mechanisms and has for an object to provide efiicient means for controlling or regulating the grinding operation upon the interior of the bore, which is being ground, reaching the predetermined dimension.

In automatic bore grinding machines, in which a gauging tool is intermittently brought into engagement with the Work for testing the progress of the grinding operation, and for cutting off the feed, when the bore has reached a certain predetermined size, as hitherto used, the gauging tool contacts with the end of the work and enters the bore only when the bore has been ground to size. Gauging mechanisms of this type, while permitting a considerable increase in production, as compared with hand gauging methods, have certain drawbacks. Since the gauge contacts with the end of the work and enters the bore only when the bore at this end has been ground to the proper dimensions, it follows that the gauge only checks the bore at its near end and that no check on the sizeof the bore at the other end or in the central portion of the work is obtained.

When grinding work of some length, or when several pieces of work are ground simultaneously, the diameter of the bore may vary somewhat along its length, due to the bending of the grinding wheel spindle under the grindin pressure and other causes. It is therefore apparent that the bore may, for instance, be oversize along its central and outer end portion without this defect becoming apparent, vwhen the ganging is carried out by the hitherto used methods., A still further disadvantage of the present method of gauging is thatthe end portion of the bore is not so well adapted for gauging purposes as the central portion, for which reason gauging at the end of the bore gives uncertain results.

My present invention provides an improved method and means for automatically checking the progress of a metal removing operation, such as grinding, within the bore of a work piece and consists mainly in the provision of a gauging mechamsm having a portion designed to enter the bore of the work piece and gauge the diameter of such bore at an intermediate point in its length. This is preferably done once for each complete traverse of the grinding element.

This device is intended for use in a bore grinding machine having a reciprocatory grinding wheel and is primarily designed for gauging across the diameter within the bore of a work piece at each outward traverse of the grinding wheel. The contacting element of the gauge, held in an inactive position, enters the bore at one end while the grindin wheel is moving toward theother end, an when so entered the contacting element is urged by spring pressure into its active or contacting position. The contact,

ing faces or points of the gauge represent its longest or gauging dimension, which dimension preferably corresponds to the finished diameter of the work piece.

The gauge is preferably pivotally supported and is tilted so that its longest or The preferred mode of carrying out -my invention is to employ a gauging instrument which is introduced into the work in an inactive position and which is yieldingly urged forward in an active or gauging position While within the work piece.

The preferred form of carrying out this invention is illustrated in the accompanying drawings, in which:

Figure 1 shows a side elevation of a grinding machine equipped with gauging mechanism according to the invention.

Fig. 2 shows a top view of the same machine.

Fig. 3 shows on a larger scale and partly in horizontal section a. top view of the work holding chuck and the gauging mechanism.

Fig. 4 is .an end View of the gauging mechanism.

Fig. 5 a detail View of the gauge.

Fig. 6 is an enlarged view of the parts shown in Fig. 3, some portions being broken away, this view showing the gauge within the work and in a. position which it assumes when the work has reached its predetermined, finished diameter, and

Fig. 7 is a still further enlarged View of "the gauging member showing this as applied to a work piece. which has not quite reached the prescribed diameter.

The grinding wheel 1 is shown carried by a spindle 2 rotatably mounted within a quill 3 which is supported on a carriage 4i mounted for reciprocation in a'well-known mannor on the machine frame 5. The amplitude of the excursions of the reciprocation of the -arriage are shown as being controlled by means of a pair of dogs 6 and 7 mounted on a wheel 8 and adapted to engage a stop 9 carried byv the machine frame for shifting a clutch (not shown) and causing the reversal of the carriage movement. The stop 9 in the illustration is fixed to the core of an. electro-magnet 10 in such a manner that when the magnet is energized the stop is withdrawn and permits the free passage .of either of the dogs 6 and 7. The reversing mechanism illustrated is well-known in the art and forms no part of the present invention.

The'carriage 4 is shown attached to a reciprocatory table 11 on which is mounted a plate 12, one side of which is formed as a cam 13. The plate may be adjusted in a direction longitudinally of the line of the carriage traverse and locked in position by means of a nut 14 on a bolt 15 slidable in a slot 16 formed in a guide 17 attached to the table 11.

The work pieces upon which the grinding wheel 1 in the illustration is designed to work are illustrated in Figs. 3 and 6 as a number of anti-friction bearing rings 18 which are held in the working position of the machine by means of a work holder which is mounted on the machine frame for rotation. In the illustration the work holder comprises a body portion 19 having at one end a flange 20 bolted to the flange 21 of a hub 22 secured to the hollow rotary spindle 23 of the machine. This spindle is mounted in bearings located in bearing boxes 24 and 25 the details of which need not be particularly described since they form no part of the present invention.

The forward or work holding end of the chuck body 19 is provided at its forward end with an outwardly flaring conical seat- 26 which receives the chucking jaws 27, the outward faces of which correspond with the taper of the face 26, which faces are preferably at the angle of repose. The inner faces 28 of the jaws 27 are formed to engage the work pieces. The outer or engaged face of the work pieces are, in the illustration, substantially cylindrical. Consequently the faces 28 are disposed on substantially cylindrical lines. l

The adjustment of the chucking jaws, which are quite similar to a well-known form of pilot bushing or collet of a pot chuck, is effected by means of a ring 29 having screw threaded engagement with the wall of a circular recess 30 formed in the front face of the body member 19. The ring 29 is shown furnished with spanner engaging sockets 31.

The rings are actually clamped in the aws by means of a removable front plate 32 shown as carrying a ring 33, and held to it by pins 34, such ring having screw threaded engagement with a thread 35 formed on the front end of the chuck body 19. The plate 32 has a ring-shaped work-piece engaging portion 36. It is also provided with spanner holes 37. w

The plate 32, in its contacting portion 36, presses the work pieces, the rings-18, inward and against the front end of a sleeve 38 which is located in the body 19 at a position which is free of the jaws 27; the sleeve in turn being pressed against the front face of the hub 22. The back end of the sleeve 38 is provided with a collar 39 which is dis posed in an annular groove in the back end of the body 19 so that a shoulder of this collar engages a shoulder of the body'as at 40 for preventing the-dislodgment of the sleeve when the clamping pressure is removed.

As the grinding wheel moves toward the left ,in the various figures of the drawings it enters the bore of the work pieces 18 held in the work holder or chuck l9, and the cam 13 engages a roll mounted on the arm 46 of the head of a T-lever 47 pivoted at 470 on the machine frame 5.

The roll is pressed outward by the cam turning the lever clockwise against the action of a spring 48 which is secured to the other arm 49 of the head of the T-lever. The spring 48 is also fastened to the eye of a pin 50 which passes through a boss 51 of the machine frame. The various parts of the gauging mechanism now have assumed the positions shown in Fig. 3.

The manner in which the gauging operation is performed is as follows: As the grinding wheel 1 moves outward in the bore 52 of the work pieces held in the chuck the table 11 moves toward the right and the roll 45 rolls up the cam face 13, the T-lever 47 being turned counter-clockwise under the action of the spring 48. The lever 47 is formed with an eye or opening 53 through which a tube 54 passes. This tube is really the gauge carrying member. The tube is shown provided at its outer end with a hose connection 55, by means of which coolant is supplied to the work and the grinding wheel. The tube 54 is attached to the lever 47 by means of pivots 56 in such a manner that as the lever swings back and forth a straight reciprocating movement is imparted to the tube which is slidably mounted in bearings at 57 and 58.

Surrounding the tube 54 is a second tube 59 which is slidably mounted in bearings at 60 and 61. The tube 59 is guided at its outer end by a collar 62 attached by means of an arm 63 to a sliding bar 64. This bar 64 is slidably mounted in bearings, one of which is formed in a boss 65 on the machine frame and the other of which is formed in the boss 51 to which the end of the spring 48 is at- An'adjustable stop device 71 engages the col-- lar 62 as the tube 59 moves toward the right under the influence ofthe coiled spring 66. Assuming that the grinding wheel 1 and the table are moving toward the right in Figs. 3 and 6, the lever 47 will then swing, under the influence of the spring 48, counter-clockwise moving the tube 54 and collar 69 toward the right. The spring 66, Working through the arm 63 and the bolt 68 keeps the lock nuts pressed against the collar 69.

In other words the bar 64, the arm 63, the collar 62 and the tube 59 move toward the right until they are stopped by the stop device 71. The movement of the lever 47 and the tube 54 is, however, continued until it is arrested by the gauge, the details of which are fully described below. The tube 54 is permitted to continue its movement after the movement of the tube 59 has been arrested due to the fact that as explained above the bolt 68'passes freely through the collar 69, thus permitting relative axial movement between the parts.

The form of the gauge member or work contacting element which is illustrated is quite similar to that shown and described in Patent No. 1,793,763 issued to me February 24, 1931 for Tolerance gauge. The enlarged illustration of this gauge is shown in Fig. 7. The form of the gauge illustrated in the patent is for checking maximum and minimum dimensions and is essentially a tolerance gauge.- The present machine is tube 54 continues its movement alone.

designed to check or register when the gauge I indicates the maximum dimension, but is not concerned so faras its gauge element is considered. The gauge comprises a body member 72 which comprises the equatorial zone of a sphere, the diameter of the great circle thereof being smaller than the diameter of the work pieces which are supplied to the machine and before they have been acted upon by the grinding wheel. A boss 73 is imposed upon such spherical surface and has a spherical outer surface concentric with the body portion. The boss 73 is shown as being, wholly disposed upon one side of the great circle 74 defining the equator of the spherical body.

The diameter 75, taken from the face of the boss 73 to a point directly opposite, represents the diameter of the .finished bore. This body 72 is shown mounted on the end of the tube 54 as follows: A hub or collar 76 is rotatably mounted on the tube 54 and is held in place by .a nut 77. This collar 1s shown provided with a pair of diametrically opposite holes into which extend pins 78' and 79 which are screwed into the body 72 of the gauge and form a pivot about which such gauge body may be turned. When the gauge body is turned in the position shown in Fig. 3 it may freely enter the work pieces provided, of course, its diameter 74 is less than the diameter of the work piece.

The body 72 can only be moved into. a position with its greater diameter 75 coincident with a diameter of the bore of the work piece when such latter diameter is at least as large as the diameter 75. The inner end of the tube 59 is provided with a sleeve 79 upon which is rotatably mounted a collar 80 held in place by a nut 81. The collar 80 is slidably mounted in the sleeve 38 in the chuck 19 and is caused to rotate with the latter by means of a screw 82 axially movable in a groove 83 in thesleeve 38. A link 84 is fixed to the collar 80 at one end, the other end being pivotally attached to the gauge body 72. The link 84 imparts the rotation of the chuck from the collar 80 to the gauge body 72 which thus rotates about the tube 54 with the same speed as the chuck or, in other words, with the same speed as the work pieces 18. Th1s 1s of importance in order to prevent wear on the gauge when it comes in contact wlth the work.

As previously shown, when the grinding wheel moves toward the right, that 1s to- -avard the. outer end of the bore, the two tubes 54 and 59 also move toward the right simultaneously and with the same speed until the movement of the tube 59 1s arrested by the stop device 71 after which tllie s the grinding wheel is withdrawn toward the outer end of the bore the gauge, which is mounted on the end of the tube 54, follows it at a distance regulated by the adjustment of the cam 13 and enters the bore of the work. When the gauge has proceeded a certain desired distance, which is regulated by the adjustment of the stop device 61, the movement of the tube 59 is arrested. The link 84 stops thus preventing the further movement of that side of the gauge to which it is attached. The tube 54 continues its movement under the influence of the spring 48 and the center of the gauge is therefore advanced in relation to the side, which is held stationary by the link 84.

The gauge is therefore tilted until its greatest diameter 75 is brought into engagement with the work. If the bore of the work is not yet in size the tilting movement of the gauge and consequently its axial movement in the bore of the work will be arrested. On the return of the grinding wheel towards the back of the bore the roll 45 is engaged by the cam 13 and the gauge is withdrawn leaving the way open for the grinding wheel.

If the bore has been ground to size the tilting movement of the gauge is carried farther. This allows the tube 54 to be advanced farther toward the right than before the hole is in size. A contact-85 on the collar 69 comes into engagement with another contact 86 thus closing an electric circuit 87 and energizing the magnet 10. The stop 9 is lifted allowing it to pass over the dog 6. It should be observed that contact always occurs when the gauge is on its way in, that is when the grinding wheel is on its way out. Since the stop 9 is then lifted, the dog 6 cannot reverse the movement of the carriage 4 and the carriage continues its movement removing the grinding wheel from the bore of the work.

It is apparent that other modifications of the device may be made without departing from the spirit'of the invention.

Having described my invention, I claim and desire to secure by Letters Patent:

1. In a device of the character described, the combination with a bore forming machine having a work holder and a working tool and having relative reciprocator movement between the work holder and the working tool and means for imparting the reciprocatory movement, of a gauge constructed and adapted, when in one angular position to freely enter the unfinished bore of the work piece and when in another lzrngular position to traverse the finished ore.

2. The combination with a bore forming the work holder when in one relative position, but unable to traverse such unfinished bore when in another relative position, means controlled by the relative reciprocatory movement for introducing the gauge into and causing it to traverse the bore, means for initially holding the gauge in the first above recited position, and elastically yieldable means tending to move the gauge into the second above recited position.

3. The combination with a work holder and a bore forming tool, of a gauge having two dimensions, its greater being equal to the finished diameter of the work piece, means for introducing the gauge into the bore tilted so that its greater diameter is out of gauging relation to the work piece and yieldable means for tilting the gauge to bring its greater diameter into a'position radially of the axis of the bore.

4. In a device'of-the character described, the combination with a bore forming machine having a reciprocatory working tool and means for reciprocating it, of a gauge constructed and'adapted, when in one position, to freely enter the unfinished bore of the work piece and when in another position to pass through the finished bore, means for carrying the gauge into the bore being formed in a work piece, means for normally holding the gauge in its first recited position, and means active on such holding means and tending to move the gauge into its second recited position.

5. The combination with a bore forming machine having a rotary work holder and a reciprocatory working tool and means for reciprocating it, of a gauge constructed and adapted to freelyenter andtraverse an unfinished bore of a work piece located in the work holder when in one relative position, but unable to traverse such unfinished. bore when in another relative position, a device controlled by the toolin its traverse for introducing the gauge into the bore and causing it to traverse the same at each withdrawal of the working tool, means for initially holding the gauge in the first above recited position, and elastically yieldable y means tending to move the gauge when so introduced into the secondabove, recited position. a

6. The combination with a bore forming machine having a rotary work holder and a reciprocato-ry working tool and means for reciprocating it, of a gauge constructed and adapted to freely enter and traverse an unfinished bore of a work piecelocated in the work holder when in one relative position, but unable to traverse such unfinished bore when in another relative position, a device controlled by the tool in its traverse for introducingthe gauge into the bore and causing it to traverse the same at each "withdrawal of the working tool, means for inireciprocat ory working tool and means for reciprocating it, of a gauge constructed and adapted to freely enter an unfinished bore of a work piece located in the work holder when in one relative position, but unable to assume another relative position'in such unfinished bore, a device controlled by the tool in its traverse for introducing the gauge into the bore at each withdrawal of the working tool, means for initially holding the gauge in the first above recited position, and elastically yieldable means tending to move the gauge when so introduced into the second above recited position.

8. The combination with a bore forming machine having a rotary work holder and a reciprocatory working tool and means for reciprocating it, of a'gauge constructed and adapted to freely enter an unfinished bore of a work piece located in the work holder when in one relative position, but unable to assume another relative position in such unfinished bore, a device controlled by the tool in its traverse for introducing the gauge into the bore at each withdrawal of the working tool, means for initially holding the gauge in the first above recited position, and elastically yieldable means tending to move the gauge when so introduced into the second above recited position, and -means actuated by the gauge introducing device for causing the reciprocation of the working tool to cease upon the gauge assuming such second recited position.

9. The combination with a bore forming machine having a work holder, a working tool mounted for reciprocation at one side of the'work holder, of a gauge constructed and adapted to freelyenter an unfinished bore of a work piece located in the work holder when in one relative position, but unable to traverse such unfinished bore when in another relative position, a bar mounted for reciprocation at the other side of the work holder, the gauge being loosely mounted on such bar, means for initially holding the gauge in the first abovk recited position,

and elastically yieldable means tending to move the gauge when introduced into the work piece into the second above recited .po-

sition, and meansactuated by said elastically yieldable means for causing the reciprocation of'the working tool to cease upon the gauge assuming such second recited pos1t1on. i 4

10. In a bore forming machine the com bination with a frame of a work holder. mounted on the frame, a carriage reciprocatory on the frame toward and from the work holder, means for reciprocatin the carriage, a working tool mounted on tie carriage, a gauge constructed and adapted to freely enter an unfinished bore of the work piece located in the work holder when in one relative position, but unable to assume another relative position in such unfinished bore, a bar mounted on theframe for reciprocation and means for recpircoating it comprising a T-shaped lever having its upright portion pivotally connected to the bar, one end of. its head being in position for the engagement of a cam mounted on the working tool carriage, such cam having aspring conrounding such bar and a link connecting the end of such sleeve to the gauge, and spring means between the T-shaped lever and-such sleeve tending to move the gauge into its second recited position.

11. In a bore forming'machine the combination with a frame of a work holder mounted on the frame, a carriage reciprocatory on the frame toward and from the work holder, means for reciprocating the carriage, a working tool mounted on the carriage, a gauge constructed and adapted to freely enter an unfinished bore of the work piece located in the work holder when in one relative position, but unable to assume another relative position in such unfinished bore, a bar mounted on the frame for reciprocation and means for reciprocating it comprising a T-shaped' lever having its upright portion pivotally connected to the bar, one end of its head being in position for the engagement of a cam. mounted on the working tool carriage, such cam having'a spring connected to the other side of the head of the T-lever and connected to the frame in such manner that the spring tends to move the bar toward the work holder and the cam engagement tends to move the bar away fromthe work holder, a tubular sleeve surrounding such bar and the gauge, and spring means between the T-shaped lever and such sleeve tending to move the gauge into its second recited posi-.

'tion, and a circuit closing device associated a link connecting the end of suchsleeve to angular position, means for introducing the gauge into and causing it to traverse the bore, means for' initially holding the gauge in the first above recited angular position, and means tending to move the gauge into the second herein above recited position.

Signed at Gottenborg, Sweden, this 26th day of September, 1931.

HILDING VALDEMAR TfiRNEBOl-IM.

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