US 2818687 A
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R. A. QUIMBY INTERNAL GRINDING MACHINE Jan. 7,1958
5 Sheets-Sheet 1 Filed July 18. 195s INVEN TOR. RALPH A. QUIMBY I ih'oaugvs Jan. 7, 1958 .Filed July 18. 1956 R. A. QUIMBY 2,818,687
INTERNAL GRINDING MACHINE 3 Sheets-Sheet 2 INVENTOR. I RALPH A. QUIMBY ATTO RN EYS R. A. QUIMBY INTERNAL GRINDING MACHINE Jan. 7, 1958 3 Sheets-Sheet '3 Filed July 18, 1956 INVENTOR/ RALPH A. QUIMBY- BY 0M, (5m
ATTOR N EYS INTERNAL MA 2 Application July 18, 1956, Serial No. 598,580
8 (Llainrsa (Cl. 51-95) This invention relates to internal grinding machines and particularly to work sizing of a round workpiece which is supported by an outer peripheral surface and an end surface while being rotated and while the rotating abrading tool is being applied to an internal surface.
This application is a continuation-in-part of application Serial No. 354,197, filed May 11, 1953 issued as U. S. Letters Patent No. 2,758,427, dated August 14, 1956.
In the said co-pending application means are shown and described for precisely supporting a rotating workpiece on a fixed axis by support means in contact with an outer peripheral surface of the workpiece while the grinding tool is being applied to the internal surface. Also described and shown as associated with the peripheral surface support means is a rotating backplate positioned with respect to the peripheral support means so as to make contact with an end face of the rotating workpiece and against which the workpiece is urged by pressure means such as a pair of rolls in contact with the opposite end of the workpiece. The backplate together with its associated pressure means therefore acts to position the workpiece in an axial direction to keep it on the peripheral support.
In such machines it is desirable to rotate the workpiece by driving the backplate, the rotative force being imparted to the workpiece by frictional contact of the backplate. It is necessary to cause the workpiece to be urged against its peripheral support and one such method is to position the backplate on an axis which is eccentric to the support determined axis of the workpiece and in a relationship to it such that rotation of the backplate not only drives the workpiece but also urges it radially against the peripheral support.
In such a machine the most accurate means for sizing the workpiece for completion of the finishing operation is to gage the work and a desirable type of gage to use for finished work sizing is a plug gage which enters the work when the hole formed by the internal surface being ground has been sufllciently enlarged by the finish grinding operation.
Since it is necessary to mount the plug gage concentric with the support determined axis of the workpiece and since the plug gage has to be mounted on the same side of the workpiece as the backplate because of the fact that the grinding tool is applied to the workpiece from the opposite end it has been found necessary in prior machines also to mount the backplate concentric with the support determined axis of the workpiece so that the plug gage could be supported within the backplate. Such an arrangement thereby loses the advantage of mounting the backplate eccentric to the support determined axis of the workpiece.
Accordingly it is the object of the present invention to provide mechanism for supporting and rotating a plug gage concentric to the support determined axis of the workpiece in combination with means for supporting and rotating a backplate eccentric to the support determined atent O axis of the workpiece, in order to obtain the advantages of the use of an eccentric backplate while using a plug gage.
An embodiment of the invention is herein described in connection with the drawings in which:
Fig. 1 is an elevation view partly in section of the part of an internal grinding machine which embodies the invention.
Fig. 2 is a top plan view of part of the mechanism shown in Fig. 1 together with a drive motor and associated mechanism.
Fig. 3 is a view from the right-hand end of Fig. 1 taken along the lines 33 thereof.
Fig. 4 is a top plan view of part of the mechanism shown in Fig. 3.
In the drawings a work head indicated at A supports a workpiece W having an internal surface S, and an abrading tool T is supported on a tool head B for introduction into the workpiece W and application to the internal surface S. The work head A is supported on a traverse table 10 which is slidable on a base 12 and in a V-way 11 to the left and right as viewed in Fig. 1 to move the grinding wheel T relatively in and out of the work for loading work and truing the wheel T and for reciprocating the wheel T back and forth across the surface S during grinding.
The wheelhead B is slidable on Ways 13 on the base 12 in a direction transverse to the movement of the table 10 to feed the tool T against the workpiece surface S by suitable feed mechanism indicated at 15.
The traverse table 10 is actuated to the left and right by suitable mechanism which may be fluid pressure means including a piston 17 connected to the table 10 and operating in a cylinder 18. Fluid pressure is alternately supplied and exhausted to and from the cylinder 18 through fluid lines 19 and 20, a pressure line 21 and exhaust lines 22 and 23 and controlled by a valve 25 having a plunger 26 actuated to reverse the flow of fluid pressure to the cylinder 18 by an arm 31 pivoted at 32 and connected at 33 to a plunger rod 34. For oscillation of the tool T across the surface S during grinding the arm 31 is oscillated by a pair of dogs 38 and 39 attached to the table 10. The dog 39 is pivoted at 40 and is lifted out of the Way to allow the table 10 to run out to the left at the completion of grinding by a solenoid 42 having a plunger 43 whose upper portion 44 makes contact to raise the dog 39 when the solenoid 42 is energized by suitable gage operated control mechanism not shown. After the traverse table 10 has been moved out to the left to run the tool out of the work for reloading and truing, the table 10 may be run back into the work by operation of a handle 30 on the arm 31.
The workpiece W as best seen in Fig. 3 is supported on a fixed support-determined axis by a peripheral work support indicated at which may include arcuate shoe elements 51, 52 and 53. The support shoes 51 and 52 may be fixed and the support shoe 53 may be pivoted at 54 and locked in position during grinding by a reed 55 held against movement by a fluid pressure piston 56 as more particularly described and claimed in said co pending application Serial No. 354,197 issued as U. S. Letters Patent No. 2,758,427 dated August 14, 1956. The support elements 51, 52 and 53 make contact with the external peripheral surface P of the workpiece W. The workpiece W is thus held immovable radially while the tool T is being fed to the right as seen in Fig. 3 against the internal surface of the workpiece.
To hold the workpiece W on its peripheral support 50, a circular backplate 60 is positioned with respect to the support 50 so as to make contact with one end e of the workpiece W and a pair of rolls 62 and 63 carried on a yoke 65 pivotally mounted at 66 are urged against the opposite end e of the workpiece to force the workpiece against the backplate 60. The outer end 67 of the yoke 65 is urged outwardly, i. e., downwardly as viewed in Fig. 4, by fluid pressure means including a piston 68 operating in a cylinder 69 to urge the rolls 62 and 63 against the workpiece.
The backplate 60 is carried on a hollow spindle 70 which is rotatably mounted in bearings 72 and 73 supported on an upward extension 74 of the traverse table 10. The backplate 66 is mounted with its axis eccentric to the support-determined axis of the workpiece W. The eccentricity is exaggerated and for clarity is shown in the plane of the paper in Fig. 1. The plane of the eccentricity is best seen in Fig. 3. Thus when the backplate 60 is rotated in a clockwise direction as seen in Fig. 3 it not only drives the workpiece W by reason of its frictional engagement therewith but also exerts a component of force on the workpiece W tending to drive it downwardly against the peripheral support 50.
The backplate 69 is driven by an electric motor 3%) through a belt 81 and a pulley 82 mounted on the lefthand end of the backplate spindle 70.
A plug gage 85 is mounted concentric to the supportdetermined axis of the workpiece W and therefore eccentric to the axis of the backplate 6t and is carried on a gage spindle 86 extending through the hollow backplate spindle 70 and the backplate 60. The spindle 86 is slidable and rotatable in a sleeve 88 fixed in an upper extension 89 of the table thereby forming a cantilever support for the gage 85. The gage 85 is also rotated by the motor 80 as seen in Fig. 2 through a belt 949 and a pulley 91 fixed on the rear end of the gage spindle 86.
During reciprocation of the grinding tool T across the surface S of the workpiece W the gage 85 is also reciprocated relative to the workpiece and thereby kept clear of the tool T by means of a longitudinally slidable rod 95 seen in Fig. 1 whose right-hand end 96 makes abutting contact with an abutment face 97 on the base 12 moving the rod 95 relatively to the left as the traverse table 10 moves to the right. An upwardly extending arm 10-!) mounted on the left-hand end of the rod 95 makes contact with the outer non-rotatable portion 101 of a hearing 102 whose inner portion 103 is carried axially immovably relative to the gage spindle 86 between a shoulder 105 formed by a reduced portion 106 of the spindle and the pulley 91. A pair of springs 110 and 111 extend between the outer bearing portion 101 and the upwardly extending plug gage mount 89 and urge the spindle 86 and gage 85 to the right toward the workpiece W so that reciprocation of the gage 85 is caused by the rod 95 in one direction and by the springs 110 and 111 in the opposite direction.
Suitable means such as arm 115 pivoted at 116 is provided for actuation by movement of the gage into the work when the work has reached a predetermined size, and a switch 118 closed by the arm when the arm is moved in a counterclockwise direction by contact of the outer bearing member N11. to stop the feed of the wheel relative to the workpiece surface S and to withdraw the wheel from the work.
It will thus be seen that the present invention provides means by which a plug gage may be mounted concentric to the workpiece and eccentric to a blackplate on the same end of the work-piece eccentric to the workpiece.
1. In an internal grinding machine, means to support a workpiece for rotation on a support-determined axis, a hollow backplate arranged in proximity to said support means to make contact with one end of said workpiece, means including a hollow spindle rotatably to support said backplate on an axis eccentric to the said supportdetermined axis, a gage extending through said backplate and a bearing member supporting said gage on an axis concentric with said support determined axis.
2. In the combination as set forth in claim 1, said bearing member extending at least part way through said hollow spindle.
3. In the combination as set forth in claim 1, said bearing member axially slidably supporting said gage.
4. in the combination as set forth in claim 1, said bearing member rotatably supporting said gage.
5. In the combination as set forth in claim 4, means to rotate said gage.
6. In the combination as set forth in claim 1, said gage being rotatably supported by said bearing member and means to rotate said backplate and said gage.
7. In the combination as set forth in claim 6, a driving connection between said backplate and said gage.
8. In the combination as set forth in claim 1, a grinding tool applicable to a said workpiece in said support means, means to reciprocate the grinding tool relative to the backplate axially of the backplate to pass the tool back and forth across the face of the workpiece, and means to reciprocate the gage axially of the backplate in time with the said movement of the tool to keep the gage clear of the tool.
References Cited in the file of this patent UNITED STATES PATENTS 2,771,714 Schmidt Nov. 27, 1956