US2045488A - Lapping and honing machine - Google Patents

Lapping and honing machine Download PDF

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US2045488A
US2045488A US723981A US72398134A US2045488A US 2045488 A US2045488 A US 2045488A US 723981 A US723981 A US 723981A US 72398134 A US72398134 A US 72398134A US 2045488 A US2045488 A US 2045488A
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lap
laps
spindle
lapping
machine
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US723981A
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Oubridge William Arthur
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B37/00Lapping machines or devices; Accessories
    • B24B37/04Lapping machines or devices; Accessories designed for working plane surfaces
    • B24B37/07Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool
    • B24B37/08Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool for double side lapping

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  • This invention relates to lapping and honing machines of the type comprising a pair of relatively rotatable laps between which the work is carried by means of a cage or holder, and has for its object to provide improved means for moving one of the laps towards and away from the other for-the purpose of enabling the work to be placed in and removed from the .said holder or cage, and for regulating the pressure between the laps.
  • the separation of the two laps andthe control of the pressure between them is effected .by pneumatic means involving the provision in. association :with the spindle of one of said laps of the plun er or piston of a cylinder connected with a supply of air or gas under pressure controlled by appropriate valve mechanism.
  • the invention also includes a new or improved construction of the machine as a whole inwh'ich the mechanism controlling the rotary and axial movements of the upper Ilap is located below the bottom lap, the spindle of the former passing downwardly, through the centre of the latter.
  • Figure 1 is a vertical sectional view of the improved lapping machine.
  • thninvention is shown as applied to a lapping machine in which the upper lap 2 is supported and operated from below, but
  • the means employed for separating thelaps is not necessarily limited in its application to this type as it can obviously beapplied'to machines in which the'upper lap is supported and operated from above.
  • the tubular spindle 6 is itself rotatably mounted in upper and lower bearings 9 in *a central tubular member 10 of the bed or frame H of the machine.
  • the two laps are rotated simultaneously and in opposite directions from a horizontal shaft 52 which is mounted in bearings 13 carried by engaging a groove 32 in said collar.
  • the driving shaft [2 is drivenloy a belt pulley 19 which is free to rotate thereon and carries one member 20 of a clutch the other member 21 of which is keyed to the outer end of said shaft and carriesa split band 22 "adapted to be 15 expanded into frictional engagement with "the firstmember by means of a cam 23 the lever 24 of which is operated by a sliding collar '25 having :a conical end 26.
  • the plunger rod is pivotally connected by means which is pivoted at 31 in the frame ll and'at an intermediate ,part is pivotally connected with
  • the supply of compressed air to the working 35 cylinder is controlled by means of a valve 4'0 by turning which in the appropriate direction the interior .of the cylinder below orabove the plunger is placed. in communication with the air sup- In its simple form, represented in Figure 5,
  • valve 40 which may be conveniently arranged at'the front of the machine as shown in Figure 2 and is of the rotary plug type, has three-ports, viz: .an inlet port 4
  • valve may, as shown in Figure 4, be provided with an additional cylinder port 41 communicating with the upper end of the cylinder 34. In this case the valve plug would have.
  • the raising of the upper lap 2 is assisted by means of counterweights 49 which are attached to an adjustable fitting 50 on the lever 36 by cables 5
  • the purchase of the weights on the lever can be varied as the weight ofthe upper lap decreases with wear by adjusting the fitting 56 along the lever.
  • the said fitting is formed with a tapped hole 53 to receive the screw-threaded end of an axially immovable spindle 54 mounted rotatably in the lever and having itsouter end 55 adapted to receive a key whereby the spindle can be rotated.
  • the said holder will vary with the nature of the work to be lapped or honed.
  • the said holder consists of a circular plate 56 arranged between the laps and formed with a number of circular openings (not shown) to receive the rings.
  • a pair of lugs 51 are securedto the holder and theseserve to connect the holderwith a pair of crank pins 58.
  • the spindle 59 of each crank pin has secured. to it a sprocket wheel 60 and these are driven from a sprocket ,6l on the spindle 6 of the lower lap by means of an endless chain 62.
  • the crank pins By means of the crank pins the workholder is given a circular motion between the laps.
  • the crank spindles are mounted outside the pan 63 surrounding the lower lap so that the actuating mechanism for the holder is clear of the abrasive liquid in the pan.
  • the abrasive liquid is supplied to thelaps from a container 64 mounted upon the carrier plate 65 of the upper lap 2 and flows between the laps into the aforesaid, pan 63 surrounding the lower lap, being returned to said container through a pipe 66 by means of a pump which is not shown.
  • tubular spindle 6 is extended or raised so that its upper end projects an' appreciable distance above the normal level of the liquid in the said containerwhen the upper lap is lowered onto the bottom lap.
  • tubular battles 61, 68 are fitted between the upper bearing 5 and the cap 69.
  • the raising or extension of the tubular spindle has the further important advantage that it provides a better support for the spindle 3 of the upper lap against the stresses set up by the rotary movement of the latter.
  • a lappingand honing machine of the character described comprising a pair of relatively rotatable superposed laps, means for causing rotation of said laps, a work-holder located between said laps, and means extending through the rotational centers of both of said laps, said 45 means being connected to one of said laps and being adapted to have movement in an axial direction with relation to the other of said laps to cause movement of the former lap in an axial direction with relation to said other lap.
  • a lapping and honing machine of the character described comprising a pair of relatively rotatable superposed laps, a work-holder'located between said laps, means operating through the rotational center of the lower lap for moving the upper lap relatively to the lower lap along the axis of rotation, andmeans arranged below said laps'fo-r imparting relative rotary movement thereto.
  • a lapping and honing machine of the character described comprising a pair of relatively rotatable superposed laps, a work-holder therebetween, and power-operated means arranged below the laps and operating through the rotational center of the lower lap for moving the upper lap axially relatively to the lower lap.
  • a lapping and honing machine of the character described comprising a pair of superposed laps, a work-holder located between them, a rotatable tubular spindle carrying one of said laps, an inner rotatable spindle mounted in said tubular spindle and carrying the other lap, and power operated meansfor imparting relative axial movement to said spindles.
  • a lapping and honing machine of the character described comprising a pair of superposed laps, a-work-holder located between them, a rotatable tubular spindle carrying one of said laps, an inner rotatable spindle mounted in said tubular spindle and carrying the other lap, a lever connected with the spindle of one of said laps and means associated with said lever for separating said laps.
  • a lapping and honing machine of the character described comprising a pair of superposed laps, a work-holder located between them, a rotatable tubular spindle carrying one of said laps, an inner rotatable spindle mounted in said tubular spindle and carrying the other lap, a cylinder, a plunger working therein, a lever connected with said plunger and with the spindle of one of said laps and means for controlling a V supply of compressed air or gas to said cylinder.
  • a lapping and honing machine of the character described comprising upper and lower rotatable laps, a work-holdertherebetween, means for moving one lap relatively to the other in the direction of the axis of rotation, a tubular spindle for the lower lap extending through and above the upper lap when the latter is in its operative position with respect to the lower lap, a central spindle mounted in said tubular spindle and carrying the upper lap, and means common to both spindles arranged below the lower lap for rotating said spindles at different speeds.
  • a lapping and honing. machine of the character described comprising a lower lap, an upper l-ap, an abrasive liquid container carried by said upper lap, a tubular spindle for the lower lap extending above the normal level of the liquid in said container, a central spindle mounted in said tubular spindle and carrying said upper lap, a. driving shaft arranged below the lower lap and adapted to impart relative rotary movement to. said spindles and laps, a bearing in the upper endo-f said tubular spindle for said central spindle, and means associated with the upper and lower laps and adapted to co-operate together to prevent access of said abrasive liquid to said bearing.
  • a lapping and honing machine of the character described comprising a lower lap, an axially free upper lap adapted to co-operatetherewith, a work-holder located between said laps, driving mechanism operating from below said laps for imparting relative rotary movement thereto, power-operated means for separating said laps, and means associated with said upper lap for measuring the extent of its axial displacement consequent upon each lapping or honing operation.
  • a lapping and honing machine of the character described comprising a lower lap, an axially free upper lap superposed thereon, a workholder located between said laps, means operating through the rotational center of the lower lap for moving the 'upper lap relatively to the lower lap along the axis of rotation, driving mechanism for imparting relative rotary movement to said laps, a lever responsive to axial said upper lap consequent upon each lapping or honing operation.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Description

June 1936; w. A. OUBRIDGE 2,045,48
QLAIQPING AND HONING MACHINE Filed May 4, 1954 s Sheets-Sheet 1 Jame 23, W36. w. A. OUBRlbGE I 2,045,488
LAPPING AND HONING MACVHINE Filed May 4, 1934 5 Sheets-Sheet 2 23, 1936. V w QUBRHJGE 2,645,488
' LAPPING AND HONING MACHINE Filed Ma 4, 1934 3 Sheets-Sheet 3 Patented June 23, 1936 UNITED STATES PATENT OFFIE i Application May 4, 1934, Serial No. 723,981
In Great Britain May 8, 1933 10 Claims. v ((31. 51-118).
This invention relates to lapping and honing machines of the type comprising a pair of relatively rotatable laps between which the work is carried by means of a cage or holder, and has for its object to provide improved means for moving one of the laps towards and away from the other for-the purpose of enabling the work to be placed in and removed from the .said holder or cage, and for regulating the pressure between the laps. v, 7
According to the present invention the separation of the two laps andthe control of the pressure between them is effected .by pneumatic means involving the provision in. association :with the spindle of one of said laps of the plun er or piston of a cylinder connected with a supply of air or gas under pressure controlled by appropriate valve mechanism. r I
The invention also includes a new or improved construction of the machine as a whole inwh'ich the mechanism controlling the rotary and axial movements of the upper Ilap is located below the bottom lap, the spindle of the former passing downwardly, through the centre of the latter.
In the accompanying drawings,
Figure 1 is a vertical sectional view of the improved lapping machine.
alternate form of valve and its connections with the cylinder. 3 I
In the drawings, thninvention is shown as applied to a lapping machine in which the upper lap 2 is supported and operated from below, but
the means employed for separating thelaps is not necessarily limited in its application to this type as it can obviously beapplied'to machines in which the'upper lap is supported and operated from above. I
In the construction shown the upper lap 2 'is fixed to a spindle 3 which protrudes vertically through the centre of the lower lap '4 and is To- .ta'tably mounted in bearings =5 of substantial length in a "tubular spindle 6 to a flange '1 on which the lower slap is firmly secured by bolts .8. The tubular spindle 6 is itself rotatably mounted in upper and lower bearings 9 in *a central tubular member 10 of the bed or frame H of the machine.
The two laps are rotated simultaneously and in opposite directions from a horizontal shaft 52 which is mounted in bearings 13 carried by engaging a groove 32 in said collar.
of a cross-head 35 with the end of a lever 36 When the valve is turned to the position shown,
the frame of the machine. One end of this shaft carries a pair of bevel pinions l4, l5 keyed there to, said pinions meshing respectively with oppositely arranged bevel wheels I6, I 1. One of these bevel wheels .16 is fixed to the lower end of the tubular spindle .6 whilst the other ill is rotatably mounted in'a bearing l8 supported by the frame of the machine, and is in driving engagement with the splined lower end of the spindle 3 which is free to slide axially through it. I 10 The driving shaft [2 is drivenloy a belt pulley 19 which is free to rotate thereon and carries one member 20 of a clutch the other member 21 of which is keyed to the outer end of said shaft and carriesa split band 22 "adapted to be 15 expanded into frictional engagement with "the firstmember by means of a cam 23 the lever 24 of which is operated by a sliding collar '25 having :a conical end 26. "Thesaid collar is moved into and out of its operative position by means of ahand lever 21, Figure 2; mcuntedr at'the other side of the machine and connectedgby a bar 281to a crank 2'9 on a short spindle Sllthe other end of which carries a striking fork 3| 25 The raising ofthe upper lap by "pneumatic 0 power is effected "by means of a plunger 33 work- "Ingin a cylinder 34 fixed to the machine frame. The plunger rod is pivotally connected by means which is pivoted at 31 in the frame ll and'at an intermediate ,part is pivotally connected with The supply of compressed air to the working 35 cylinder is controlled by means of a valve 4'0 by turning which in the appropriate direction the interior .of the cylinder below orabove the plunger is placed. in communication with the air sup- In its simple form, represented inFigure 5,
I the valve 40 which may be conveniently arranged at'the front of the machine as shown in Figure 2 and is of the rotary plug type, has three-ports, viz: .an inlet port 4| communicating with a s'up- 45 .ply of compressed air or gas, a cylinder port 42 communicating with .the lower end of the cylinvalve plug has -a single transverse passage 44.
compressed air enters the cylinder through the pipe 45 below the plunger causing the latter to raise the lever 36 and thereby lift the upper lap '2 clear of the bottom lap, the splined lower end of the spindle 3 sliding through the bevel 55 wheel I I. The upper lap is maintained in the raised position by the air pressure so long as the valve remains open. When the valve is closed to inlet and opened to exhaust the upper lap is free to descend, its downward movement being controlled by the area of the exhaust port which may be varied by adjustment of a cook 46 so that as the upper lap, in descending, approaches the lower lap its movement is cushioned and slowed down.
Where it is desired to increase the pressure on the work beyond that due to the dead weightof the upper lap the valve may, as shown in Figure 4, be provided with an additional cylinder port 41 communicating with the upper end of the cylinder 34. In this case the valve plug would have.
two transverse passages, 44 and 48, one which establishes communication between the inlet port 4| and one end of the cylinder whilst the other establishes communication between the other end of the cylinder and the exhaust port 43.
. The raising of the upper lap 2 is assisted by means of counterweights 49 which are attached to an adjustable fitting 50 on the lever 36 by cables 5| passing over guide pulleys 52. The purchase of the weights on the lever can be varied as the weight ofthe upper lap decreases with wear by adjusting the fitting 56 along the lever. For this purpose the said fitting is formed with a tapped hole 53 to receive the screw-threaded end of an axially immovable spindle 54 mounted rotatably in the lever and having itsouter end 55 adapted to receive a key whereby the spindle can be rotated.
The form of the work-holder will vary with the nature of the work to be lapped or honed. For the purpose of lapping piston rings, for example, the said holder consists of a circular plate 56 arranged between the laps and formed with a number of circular openings (not shown) to receive the rings. At positions approximately 90 apart a pair of lugs 51 are securedto the holder and theseserve to connect the holderwith a pair of crank pins 58. The spindle 59 of each crank pin has secured. to it a sprocket wheel 60 and these are driven from a sprocket ,6l on the spindle 6 of the lower lap by means of an endless chain 62. By means of the crank pins the workholder is given a circular motion between the laps. The crank spindles are mounted outside the pan 63 surrounding the lower lap so that the actuating mechanism for the holder is clear of the abrasive liquid in the pan.
The abrasive liquid is supplied to thelaps from a container 64 mounted upon the carrier plate 65 of the upper lap 2 and flows between the laps into the aforesaid, pan 63 surrounding the lower lap, being returned to said container through a pipe 66 by means of a pump which is not shown.
In order to prevent the abrasive liquid finding its way from the lower lap' to the upper spindle bearing 5, when the machine is running with the upper lap in its operative position, the position of the upper end of the said bearing is such that, however much the lower lap 4 may be flooded, it is impossible for the liquid to reach and impair the efficiency of the said bearing. For this purpose the tubular spindle 6 is extended or raised so that its upper end projects an' appreciable distance above the normal level of the liquid in the said containerwhen the upper lap is lowered onto the bottom lap. As an additional precaution tubular baiiles 61, 68 are fitted between the upper bearing 5 and the cap 69. which closes the upper end ofthe spindle 3, said'bafiles telescoping with each other, one, 61, being fixed to the carrier plate 10 of the lower lap 4 and the other, 68, to the carrier plate 65 of the upper lap. The arrangement is such that before any of the liquid can possibly reach the bearing it must pass over the upper edge of the outer bafile 68 down between the two baflles and up again to the bearing 5. Incidentally, the raising or extension of the tubular spindle has the further important advantage that it provides a better support for the spindle 3 of the upper lap against the stresses set up by the rotary movement of the latter.
It will be understood that during the lapping or honing operation the permissible amount of material to be removed from the work is extremely small and some provision is therefore desirable for enabling the operator to know when the operation should be stopped. For this purpose there is associated with the upper lap 2 r a lever 16 which is pivoted to a fixed part of the machine, such as the adjustable pillar H on the pan 63, and rests freely upon a stud in the cap 69. When the upper lap is lowered into its operative position with respect to the lower lap 4, the free end of this lever enters the forked upper end 12 of a stationary'pillar '53 where it makes contact with the plunger 74 of a gauge 15 mounted upon said pillar. As the lapping or honing operation proceeds the upper lap, being free axially, adjustsitself to the work and this movement "is magnified at the free end of the lever where it makes contact with the plunger of the gauge. By this means an extremely fine reduction, such as a fraction of one thousandths part of an inch will show as a readily visible reading on the gauge so that the operator can work within very fine limits.
1. A lappingand honing machine of the character described comprising a pair of relatively rotatable superposed laps, means for causing rotation of said laps, a work-holder located between said laps, and means extending through the rotational centers of both of said laps, said 45 means being connected to one of said laps and being adapted to have movement in an axial direction with relation to the other of said laps to cause movement of the former lap in an axial direction with relation to said other lap.
2. A lapping and honing machine of the character described comprising a pair of relatively rotatable superposed laps, a work-holder'located between said laps, means operating through the rotational center of the lower lap for moving the upper lap relatively to the lower lap along the axis of rotation, andmeans arranged below said laps'fo-r imparting relative rotary movement thereto.
3. A lapping and honing machine of the character described comprising a pair of relatively rotatable superposed laps, a work-holder therebetween, and power-operated means arranged below the laps and operating through the rotational center of the lower lap for moving the upper lap axially relatively to the lower lap.
4. A lapping and honing machine of the character described comprising a pair of superposed laps, a work-holder located between them, a rotatable tubular spindle carrying one of said laps, an inner rotatable spindle mounted in said tubular spindle and carrying the other lap, and power operated meansfor imparting relative axial movement to said spindles.
5. A lapping and honing machine of the character described comprising a pair of superposed laps, a-work-holder located between them, a rotatable tubular spindle carrying one of said laps, an inner rotatable spindle mounted in said tubular spindle and carrying the other lap, a lever connected with the spindle of one of said laps and means associated with said lever for separating said laps. I
' 6. A lapping and honing machine of the character described comprising a pair of superposed laps, a work-holder located between them, a rotatable tubular spindle carrying one of said laps, an inner rotatable spindle mounted in said tubular spindle and carrying the other lap, a cylinder, a plunger working therein, a lever connected with said plunger and with the spindle of one of said laps and means for controlling a V supply of compressed air or gas to said cylinder.
7. A lapping and honing machine of the character described comprising upper and lower rotatable laps, a work-holdertherebetween, means for moving one lap relatively to the other in the direction of the axis of rotation, a tubular spindle for the lower lap extending through and above the upper lap when the latter is in its operative position with respect to the lower lap, a central spindle mounted in said tubular spindle and carrying the upper lap, and means common to both spindles arranged below the lower lap for rotating said spindles at different speeds.
8. A lapping and honing. machine of the character described comprising a lower lap, an upper l-ap, an abrasive liquid container carried by said upper lap, a tubular spindle for the lower lap extending above the normal level of the liquid in said container, a central spindle mounted in said tubular spindle and carrying said upper lap, a. driving shaft arranged below the lower lap and adapted to impart relative rotary movement to. said spindles and laps, a bearing in the upper endo-f said tubular spindle for said central spindle, and means associated with the upper and lower laps and adapted to co-operate together to prevent access of said abrasive liquid to said bearing.
9. A lapping and honing machine of the character described comprising a lower lap, an axially free upper lap adapted to co-operatetherewith, a work-holder located between said laps, driving mechanism operating from below said laps for imparting relative rotary movement thereto, power-operated means for separating said laps, and means associated with said upper lap for measuring the extent of its axial displacement consequent upon each lapping or honing operation.
10. A lapping and honing machine of the character described comprising a lower lap, an axially free upper lap superposed thereon, a workholder located between said laps, means operating through the rotational center of the lower lap for moving the 'upper lap relatively to the lower lap along the axis of rotation, driving mechanism for imparting relative rotary movement to said laps, a lever responsive to axial said upper lap consequent upon each lapping or honing operation.
WILLIAM ARTHUR. O'UBRIDGE.
US723981A 1933-05-08 1934-05-04 Lapping and honing machine Expired - Lifetime US2045488A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3035377A (en) * 1958-12-22 1962-05-22 Bovensiepen Hans-Friedrich Lapping machine
US3691694A (en) * 1970-11-02 1972-09-19 Ibm Wafer polishing machine
US4069621A (en) * 1976-06-17 1978-01-24 Intreprinderea "Mecanica" Plopeni Apparatus for machining bearing rolls
WO1999001255A1 (en) * 1997-07-04 1999-01-14 Lidköping Machine Tools AB Double face abrading machine
US6210259B1 (en) 1999-11-08 2001-04-03 Vibro Finish Tech Inc. Method and apparatus for lapping of workpieces

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3035377A (en) * 1958-12-22 1962-05-22 Bovensiepen Hans-Friedrich Lapping machine
US3691694A (en) * 1970-11-02 1972-09-19 Ibm Wafer polishing machine
US4069621A (en) * 1976-06-17 1978-01-24 Intreprinderea "Mecanica" Plopeni Apparatus for machining bearing rolls
WO1999001255A1 (en) * 1997-07-04 1999-01-14 Lidköping Machine Tools AB Double face abrading machine
US6176767B1 (en) 1997-07-04 2001-01-23 Lidkoping Machine Tools Ab Double face abrading machine
AU731846B2 (en) * 1997-07-04 2001-04-05 Lidkoping Machine Tools Ab Double face abrading machine
CN1078517C (en) * 1997-07-04 2002-01-30 利得雪平机器工具公司 Double face abrading machine
US6210259B1 (en) 1999-11-08 2001-04-03 Vibro Finish Tech Inc. Method and apparatus for lapping of workpieces

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