US2797531A - Honing machine with automatic gaging device - Google Patents

Description

July 2, 1957 E. Y. sEBoRG HONING MACHINE WITH AUTOMATIC GAGING DEVICE Filed Aug. 1, 1955 5 Sheets-Sheet l van Je CRT-romv'f July 2, 1957 E. Y. SEBORG 2,797,531

HONING MACHINE WITH'UTOMTIC GAGING DEVICE K Y 5 Sheets-Sheet 2 Filed Aug. 1, 1955 July 2, 1957 E. Y. sEBoRG HO-NING MACHINE WITH AUTOMATIC GAGING DEVICE 5 Sheets-Sheet 3 vsn-ro a rrLe JWQS HoN'ING MACHINE WITH AUTOMATIC @AGING DEVICE Earnest Y. Seborg, Rockford, ill., assigner to Barnes Britt Co., Rockford, Ill., a corporation of illinois Application August 1, 195s, sensi No. 525,736 s Claims. (ci. sr-szi) This invention relates to automatic machines for honing work bores to'a finished diameter determined by an associated sizing device comprising a gaging plug which is moved into and out of feeling engagement with one end of the work fbore during a part of a reciprocation of the hone when the latter is spaced from the bore end to be gagcd.

In gages of the above character, as heretofore used, the plug has been moved into and out of feeling engagement with the bore end at comparatively high speed equal to the desired high speed of reciprocation of the hone itself. The resulting sudden impact with the bore not only interferes with proper centering of the plug in the bore, but is conducive to objectionable wearing oft` of the gaging surface particularly where the size of the bore necessitates a plug and its mounting having substantial mass.

The primary object of the present invention is to overcome the above difliculty by control of the velocity of the plug at the time of its engagement with the bore independently of the speed of the hone itself.

A more detailed object is to move the gaging plug into and out of feeling engagement with the work by an independent actuator adapted to actuate the plug in timed relation to the honing cycle but at a speed substantially lower than the speed of reciprocation 'of the honing tool.

The invention also resides in the novel manner of utilizing the hone actuating mechanism and its control for governing the feeling action of the gage plug.

A further object is to control the actuation of the gage plug in a novel manner such as to avoid unnecessary and repeated engagement with the Work during the short stroking of selected parts of the work bore.

Other objects and advantages of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings, in which,

Figure l is a side elevational view of a honing machine embodying the novel features of the present invention.

Fig. 2 is a fragmentary vertical sectional View of the gaging mechanism. Y

Fig. 3 is a fragmentary sectional View taken along the line 3-3 of Fig. 2.

Fig. 4 is a schematic view and Wiring diagram.

While the invention is applicable to other types of machines, it is shown in the drawings and will be described herein in detail as applied to a, horizontal honing machine in which a radially expansible and contractible honing tool 1i) is carried by the outer end of a hollow spindle li projecting horizontally from and journaled in a head l2. The latter is guided onV the machine base 13 for reciprocatior of the tool along the axis and back and forth within the Ibore 1'4 of a workpiece 15 mounted sta'tioriar'ily in supports 16 on" the base.

Prior to' a honing operation oh thev work bore 14, ail of the parts of the illustrated machine are in their normally deenergized conditions as'V shown in Fig. 4 with the hone tl"stationaryy in a retractedV position' spaced from one 2,797,531 Patented July 2, 1957 bore reaches a desired size as detected -by a gage 62 which is moved into and out of contact with one end of the bore during reciprocation of the hone and while the latter is 4remote from the gaged bore end thereby avoiding Contact of the hone with the gage. After the bore reaches the finished size, the lhone is vstopped Within the bore and, :following its collapse away from the b'ore wall, is shifted axially to its initial retracted position.

To start the honing operation, the hone is inched forwardly into the work bore by the manual depression of a forward push button switch 19 (see Fig. 4) lto open normally closed contacts 2i? in the energizing circuit of sa withdraw soleonid 21 and to close normally open contacts 22 thereby compie'ting an energizing circuit for a reciprocate solenoid 23 between two electric power lines L1 and L2 connected to a suitable source (not shown). Upon energization of the reciprocate solenoidZ-S, avalve 24 is actuated there-hy to block ahy-pass 25 to a sump I2.5 from the outlet of a motor driven hydraulic pump 27 and render pressure uid available to mechanism which herein is` hydraulically actuated and operates to shift the head 12 back and forth relative to the work, the motor 2.7a for the pump being energized continuously during the honing loperati-on.- l n n The head shifting mechanism 28 includesV a' reversible hydraulic motor 29 which is supplied pressure fluid vfrom the pump 27 through a reversing valve 30 whose movable element 3i is shifted back and forthkby pressure fluid under the control of a pilot valve 32. In the' normal condition of the latter existing when the reciprocate solenoid 23 is first energized (see Fig. 4), the reversing valve element 31 is disposed in one end position to direct fluid to the motor 29 for rotation of its output shaft l33 in a direction to advance the head toward the work 15. The motion of the output shaft 33 istransmitted tothe head 12 through gearing 34 'and a drum 35 whichL cooperates with aan idler drum 36 to support a cable 37 extending around the two and having a connection 38 withrthe head in` a manner well known in the art. As the head leaves 'its' farthest retracted position shown in Fig. V4, a dog 39 thereon moves out of contact with the actuator of a limit switch LS2 permitting the latter to close in another circuit extending through the reciprocate solenoid 23 in parallel with or by-passing the forward inching switch contacts 22.

After advance of the head 12 far enough to project the hone itl within the work bore 14, the forward inch switch 19 is released and a run switch 40 is closed manually. This completes a circuit for energizing a run relay CRI to close contacts CRl-l thereof for completing the by'- pass circuit for the reciprocate solenoid 23 through the limit switch LS2 andfcontacts CRl-Z to completen holding circuit for the relay through normally closed contacts 41 of the forward inch switch 19,- contac't's 42 of a return switch 43, and contacts GRZ-1 of a shutdovvngrelay CE2 respectively. The reciprocate solenoidZS thus is reenergized and the head continues its advance until a reversing dog 44 thereon closes a normally open reversing switch L33 at the limit of the advance stroke of the hone. At this time, the latter has overrun the remote end of the work bore as shown in Fig. 2. y u

Closure of the reversing Switch LSS completes a circuit to a reversing solenoid45 whichacts through a linkage 4e te rotate' the movable' ele'nient 47 f the pilot valve 32 for shifting the reversing valve element 31 to its other end position thereby energizing the motor 29 for rotation in the opposite direction to retract the head 12. When the latter reaches an intermediate retracted position in which the hone has overrun the rear end of the bore 14 but is still within the latter, the reversing dog 44 closes a normally open forward switch LS4 momentarily for energizing a forward solenoid 48 which acts through the linkage 46 to shift the pilot valve element 47 to its original position for returning the reversing valve element 31 to its starting position and reversing the motor 29 for another reciprocation of the hone 10 within the bore.

As soon as the run switch is closed to transfer control of the head movement to the reversing and forward switches LS3 and LS4, a spindle switch 49 is closed manually to energize a line contactor 5G having contacts 51 which complete a holding circuit around the spindle switch and contacts 52 which close for energization of a spindle motor 53 on the head through suitable line circuits (not shown). The spindle motor acts through gearing 54 to rotate the hone spindle 11 and drives a pump 55 which supplies pressure uid to a cylinder 56 having a piston 57 connected to a hone expander rod 58 for shifting the latter axially to expand the hone. The rod extends through the hollow spindle and carries cone-shaped cams 59 at its outer end engageable with followers on the honing stones 17 in a well-known manner to shift the stones radially and outwardly against the bore wall when the rod is shifted outwardly by the piston 57, a spring 60 acting on the rod to shift the same away from the hone to permit contraction of the stones by the garter springs 18 when the spindle motor 53 is deenergized. A suitable metering mechanism 61 controls the exhaust of pressure fluid from the rod end of the cylinder to determine the rate of hone expansion.

Reciprocation of the hone 10 under the control of the reversing switches LS3 and LS4 continues until the work bore 14 reaches a predetermined diameter as detected by the gage 62. The latter is of the type adapted to feel of one end of the work bore 14 during the honing operation and to give a signal such as actuation of a switch LS1 when the bore is of the desired size. In this instance the gage feels of the end of the work bore remote from the tool head 12,` and is mounted to reciprocate between an advanced position of feeling engagement with the bore as shown in Fig. 3 and a retracted position spaced from the bore end as shown in Fig. 2 farther than the overrun of the hone so as to avoid contact of the latter with the gage.

Herein, the gage 62 is a ring having an external diameter equal to the desired finished bore diameter and formed as one end of a sleeve 63. An enlarged portion 64 intermediate the ends of the latter is of spherical external contour and seats or fits closely in a mating surface 65 formed on a ring 66 abutting against a flange 67 through which the sleeve projects to expose the gage for contact with the work. The flange 67 projects inwardly from a wall 68 integral with a bracket 73 and having a cylindrical internal surface guiding a flanged end of a sleeve 69 for reciprocation toward and away from the ring surface 65, the sleeve having a surface 70 cooperating with thering surface to define a swivel socket for the ball 64 on the gage sleeve 63. A coiled spring 71 encircling vthe sleeve 69 acts in compression between the flanged and thereof and a ring 72 abutting a snap ring on `the curved wall 68 and urges the` sleeve 69 against the ball 64 and the latter against the mating surface 65 while permitting the gage to yield axially upon contact with the work. The bracket 73 spans and is slidably supported by spaced stationary guide bars 74 paralleling the axis of the work bore 14 and rigid with a base 75 secured to the machine base 13. A tube 76 integral with the bracket 73 projects forwardly therefrom to provide a housing for the gage 62.

The sizing switch LS1 is mounted stationarily on the gage base 75 for contact of its actuator pin 77 by a bolt 78 secured adjustably to an arm 79 which projects rigidly from the flanged sleeve 69. When the bracket 73 is advanced to bring the gage against the bore end and the bore is smaller than the desired size, the gage and the flanged sleeve 69 shift rearwardly of the bracket to compress the spring 71 and the bolt 78 remains out of contact with the actuator pin 77 as shown in full in Fig. 3. Upon entry of the gage rinto the bore as shown in phantom in Fig. 3, the bolt depresses the actuator pin 77 to actuatc the switch.

In this instance, the sizing switch LS1 is normally open and is located in the energizing circuit for the shutdown relay CR-Z and the withdraw solenoid 21 in series with the normally closed contacts 20 of the manual forward switch 19 and a switch 80 which is actuated as an incident to reversal of the pilot valve element 47. The latter switch normally is open but is closed by a cam 81 fast on the pilot valve shaft 82 when the pilot valve element is in its forward position in which pressure fluid is directed to the reversing valve 30 to shift the element 31 of the latter for advance of the head 12. The withdraw solenoid 21 controls a valve 83 having a movable element 84 which normally is urged by a spring 85 to an inoperative position shown in Fig. 4 but which, when the solenoid is energized, is shifted thereby to block the mov able element 31 of the reversing valve against shifting out of its forward position and to the left as viewed in Fig. 4 to its position for retraction of the head.

The gage 62 is adapted to feel of the work 15 and shift into the bore 14 to actuate the sizing switch L82 when the head is moving rearwardly so that closure of the sizing switch has no effect until the head reaches the end of its rearward stroke and the pilot valve element 47 has begun to shift to its forward position of Fig. 4 by the forward solenoid 48 upon closure of the forward switch L54 by the dog 44. 1n the initial shifting move ment of the pilot valve element, the switch is closed by the carn 81 on the pilot valve shaft 82 thereby completing the energizing circuit through the sizing switch LS1 for the withdraw solenoid 21 and the shutdown re lay CK2. The withdraw solenoid then shifts the blocking valve element 84 to its effective position to prevent shift of the reversing valve element 31 to the left and into its forward position, such blocking action taking place before the pilot element 47 has completed its shift into the forward position. Energization of the shutdown relay CR2 results in interruption of the holding circuit for the run relay CRI at the contacts CK2-1 and in interruption of the circuit for the spindle motor contacter Si) by opening of normally closed contacts CK2-2 of the shutdown relay. The reciprocate solenoid and the spindle motor 53 thus are deenergized to terminate the honing operation with the hone 10 collapsed but still disposed within the work bore 14 at the end thereof adjacent the head.

To shift the head 12 rearwardly to its fully retracted position for removal of the finished workpiece, the manila] return switch 43 is actuated to close contacts 87 for completing an energizing circuit for the reciprocate solenoid 23 through the now closed limit switch LS2 and contacts 88 for completing a circuit through the withdraw solenoid 21. The head then shifts rearwardly until the dog 39 opens the limit switch LSZ to interrupt the circuit through the reciprocate solenoid for stopping the head in its fully retracted position.

As noted above, the gage is shifted out of feeling engagement with the end of the work bore 14 each time the hone 10 overruns the bore end on its advance stroke. In accordance with the present invention, the speed of shifting of the gage into contact with the work is controlled independently of the speed of reciprocation of the hone and is made substantially lower than the desired high hone speed so as to avoid damage to the gage due to impact of the same with the work and also to facilitate centering of the gage in the work bore. To these ends, power operated mechanism 89 separate from the hone shifting mechanism 28 is provided for reciprocating the gage backland forth between its advanced and retracted positions. While the gage may be approached toward the bore and to a position adjacent the same at a rapid rate and then moved more slowly into contact with the bore end,-the rate of advance in this instance is uniform throughout the advance stroke of the gage as permitted by the substantial length of the bore which allows ample time for approach of the gage at a slow rate during the return stroke of the hone.

In the present instance, the gage shifting mechanism 89 comprises a hydraulic actuator having a cylinder 90 secured to the gage base 75 and a piston whose rod 91 parallels the guide bars 74 and is secured to the gage bracket 73 as shown in Fig. 2 for advancing and retracting the latter and the gage 62 when pressure uid is admitted to the head and rod ends respectively of the cylinder. Pressure fluid for the cylinder is supplied herein by a pump 92 driven by a motor 93 and is controlled by a valve 94 having a rotary element 95. The latter is shiftable back and forth between a retracting position in which the rod end of the cylinder is connected to the pump and the head end is' connectedV to a sump 96 as shown in Figi. 4 and anadvancing position in which the cylinder is connected to the pump and the rod end to the sump. While they speed of advance of the gage may be controlled by change of the capacity of the pump 92,

such control is effected in this instance by an adjustable valve 97 in the pressure tiuidy line 98` between' the pump and the rod end of the cylinder. In one machine constructed as described above with a separate power actuator for the gage, a satisfactory rate of advance of the gage was foundto be about one quarter of the speed of the hone which was approximately 60 feet per minute.

l Controlv of the gage shiftingv mechanism 89, particularly the valve 94, preferably iseffe'c'ted as an incident to reci-proca'tion of the hone 10 in the work bore 14. This is accomplished simply by securement of the valve element 95 tothe pilot valve shaft 82 so that, each time the pilot valve element 47 is positioned for advance of the head, the gage valve element 95 ispositioned for' retraction of the gage bracket 73 as shown in Fig. y4. Similarly, when the pilot element is positioned for retraction of the head, the gagevalve element 95 is shifted to admit pressure fluid to the head end of the' cylinder for advance ofthe` gage.y The gage thus is shifted in response to control of the movement of the head 1-2 andthe hone 10 and: moves into contact with the work bore while the hone is retracting and'away from the bore toits retracted position where it remains as the gage overruns the bore end.

In the finishing of' long work bores, it isV desirable in some cases to short stroke selected parts of the bore by reciprocation of the hone across such parts and through a range shorter than the bore. Such short stroking is accomplished inthe present instance by a manually operated overriding, control 99 whichis effectivetotchange thedirection of the hone at any point of' its range of reciprocationy within the work bore. This control comprisesahand? lever 100 which normally' is disposedinfa neutral position shown in Fig. 4 out is swingable in one direction to close a forward switch S1 and in the opposite direction to close a retract switch S2. These switches are connected in parallel with the head actuated forward switch L84 and reversing switch L33 respectively to energize the forward and reverse solenoids d8 and 45 of the pilot valve 32. To avoid simultaneous energization of the solenoids, normally closed safety switches 101 and 102 connected in series with the respective forward and retract overriding switches S1 and S2 are coupled mechanically to the reverse and the forward head actuated switches L83 and LS4 respectively for opening of the 6 associated Safety Switch when either 0f head tiltd switches is closed. A

To avoid unnecessary and repeated contact 'of the gage 62 with the work 15, the invention contemplates retention of the gage 62 in its retracted position during short stroking of the hone. For this purpose, the gage shifting mechanism S9 is disabled as an incident to operation of the overriding control 99 by the hand lever 100 and at a time when the gage is retracted. Such disabling is accomplished in this instance by a blocking valve 103 whose shiftable element 104 normally is urged to `an inoperative position by a spring 105 but, upon energiiation of a solenoid 106, is shifted against its spring to block the flow of pressure uid in the line 107 between the gage -reversing valve 94 and the head end of the cylinder 90. An energizing circuit for the solenoid 106 is completed between the lines L1 and L2 by closure of a switch S3 which is connected in tandem rt/ithv the retract switch S2 for closure of the two in unison bythe lever 100.

During normal operation of the head shifting` mechanism 2S under the control of the Areversing switches L83 and L84, the gage valve element 95 shifts with the pilot valve element 47 for advance and retraction of the gage respectively when the hone shifts forwardly toward the gage and rearwardly away from the same, the gage entering the bore 14 to close the sizing switch LS1 for termination of the honing operation while the hone is retracting. When the hand lever of the overriding control 99 is shifted to close the forwardl switch S1y for energiz'ation of the forward solenoidv 48, the gage blocking solenoid 106 and its valve 103 are inactive, but theV gage is retainedy in its retracted position due to shifting of the'valve' elerne'nt 95 with the pilot valve element as described above. When the handlever is shifted to close the reversing switch S2 for energizing the reverse solenoid 45,' the switch S3 is also closed for energiz'a'tion of the'blocking'solehid106; The blocking valve element 104* is shifted thereby to itsactive position and the gage is retainedin its retracted position. As soon as the handflever 100 is released to return to its neutral position, the blocking solenoid 106 is deenergized and controlI of -the gage positionreturns to the reversing valve 95 which, along with the pilot valve 32, is shifted back and forth in response to energi'z'ation and deen'ergiz'ation of the forward and reversing solenoidsV 4S and 45. l

From the foregoing, it will be apparentV that the' separate power actuated mechanism 89 for shifting'. the gage 62 not only enables the gage velocity to be' controlled independently of the speed of the hone 10, but also makes it p'ossibletor'ender'the gage inactive during short strok'- ing ofthe hone. The gage thus may be shifted into'feeling contact with the work 15 at a speed slow enough to avoid objectionable wearing off ofthe gaging surfaces while insuring' that the gage is centered with respect to the'bo're for properfe'eling action. By retaining the gage in its retracted position during short strokingthe service life of the gagefis increased due toelimination of unnecessary contact with the work. With the gage valve element 95 connectedv tothe pilot'valve shaft 47, the hone shifting'mechanism 28 is utilized to govern" the feeling movement'of the gage therebyy simplifying the control.

I claim' as irny invention:

1f. In a honing-machine', the'combina'tionof, a support for holding a workpiece having a bore to be honed, a head guided for reciprocation along the axis of said bore, a spindle journaled in and projecting from said head along said axis and carrying a honing tool at its outer end, reversible power actuated mechanism for advancing said head to project said tool into said bore and then to reciprocate the tool within the bore, a first control for ener gizing said mechanism to reciprocate said hone the full length of said bore and through opposite ends thereof, a second control for said mechanism selectively operable to override said irst control for reciprocation of said hone in said bore through a limited range shorter than the bore, a gage guided for reciprocation along said axis and into and out of contact with one end of said bore and adapted to enter the bore when `the latter'reaches a predetermined diameter, mechanism for advancing and retracting said gage into and out of contact with said bore end and including a power actuator, first control means for said gage mechanism operable to actuate the latter in the reciprocation of said head for retracting said gage away from said bore end during advance of said tool toward the bore end and advancing the gage into contact with the bore end during shifting of the head in the opposite direction, and second control means for said gage mechanism activated in response to operation of said overriding control for retaining said gage in a retracted position spaced from the bore during reciprocation of said hone in said limited range.

2. In a honing machine, the combination of, a support for holding a workpiece having a bore to be honed, a head guided for reciprocation along the axis of said bore, a honing tool carried by a spindle journaled in and projecting from said head along said axis, power actuated mechanism for advancing said tool into said bore and then to reciprocate the tool within the bore to hone the latter, a tirst control for said mechanism for reciprocating said hone the full length of said bore and through opposite ends thereof, a second control for said mechanism operable when actuated to override said first control and reciprocate said hone in said bore and through a limited range shorter than the bore, a gage guided for reciprocation along said axis and into and out of contact with the end of said bore remote from said head and adapted to enter the bore when the latter reaches a predetermined diameter, a reversible power actuator for reciprocating said gage into and out of contact with said bore end, means for energizing said actuator to retract said gage away from said bore during advance of said hone toward said bore end and to advance said gage into contact with the bore as an incident to retraction of the hone, and means for disabling said actuator with said gage retracted as an incident to actuation of said overriding control.

3. In a honing machine, the combination of, a support for holding a workpiece having a bore to be honed, a head guided for reciprocation along the axis of said bore, a spindlerjournaled in and projecting from said head along said axis and carrying a honing tool at its outer end, first power actuated mechanism for advancing said tool into said bore and then to reciprocate the tool within the bore at a predetermined speed to hone the bore, a gage guided for reciprocation along said axis and into and out of contact with one end of said bore and adapted to enter the bore when the latter reaches a predetermined diameter, a second power actuated mechanism for reciprocating said gage into and out of contact with said bore end, the speed of advance of said gage into Contact with said work by said second mechanism being substantially slower than said predetermined speed of hone reciprocation, a control for said first mechanism including a member shiftable back and forth to energize the mechanism to reciprocate the hone the full length of said bore and through opposite ends thereof, and a control for said second mechanism including said member and operable to energize the mechanism to shift said gage away from said one bore end during advance of said hone toward the end and to shift the gage into contact with the end as an incident to shifting of the hone in the opposite direction.

4. ln `a honing machine, the combination of, a support for holding a workpiece having a bore to be honed, a head guided for reciprocation along the axis of said bore, a spindle journalled in` and projecting from said head along said axis and carrying a honing tool at its outer end, power actuated mechanism for advancing said head to project said tool into said bore and then to reciprocate the tool within the bore and through opposite ends thereof, a gage guided for reciprocation along said axis and into and out of contact with one end of said bore and adapted to enter the bore when the latter reaches a predetermined diameter, mechanism for advancing and retracting said gage into and out of contact with said bore end and including a power actuator, and control means for said gage mechanism operable to actuate the latter in timed relation to reciprocation of said head to retract said gage away from said bore end while the tool is spaced from the bore end and to advance the gage into contact with the bore end during shifting of the tool away from the end, the speed of advance of said gage into contact with said work by said gage mechanism being substantially slower than the speed of reciprocation of said hone by said head reciprocating mechanism.

5. In a machine for honing the bore of a stationarily mounted workpiece, the combination of, a tool head guided for reciprocation along thc axis of said bore, a spindle journaled in and projecting from said head along said axis and carrying a honing tool at its outer end, power actuated mechanism for shifting said head to advance said tool into said bore and then to reciprocate the tool within the bore, said tool overrunning opposite ends of said bore at opposite ends of the tool reciprocation, a gage guided for reciprocation along said axis and into and out of contact with one end of said bore and adapted to enter the bore when the latter reaches a predetermined size, separate power actuated mechanism for reciprocating said gage between an advanced position of feeling engagement with said bore end and a retracted position spaced from the bore end farther than said tool when the latter overruns the end, the speed of advance of said gage into contact with said bore end by said gage mechanism being substantially slower than the speed of reciprocation of said tool by said head mechanism whereby to avoid damage to said gage by impact with the workpiece while facilitating centering of the gage in the bore, and means for actuating said gage mechanism in timed relation to reciprocation of said tool to advance said gage into contact with said bore end while the tool is spaced from the end and to shift the gage to said retracted position before the tool overruns the end in its return movement whereby to avoid contact of the tool with the gage.

References Cited in the file of this patent UNITED STATES PATENTS 1,799,763 Raule Apr. 7, 1931 1,996,842 Stevens Apr. 9, 1935 2,251,607 Astrowski Aug. 5, 1941 2,677,921 Grobey May 11, 1954

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