US2844921A - Grinding machine-steadyrest - Google Patents

Description

July 29, 1958 O E-. -HILL 2,

- GRINDING MACHINE-STEADYREST Filed Jan. '24, 1955 2 Sheets-Sheet 1 INVEN I'OR v ,O/vA E. HILL A TTOEIVEY July 29, 1958 o. E. HILL 2,

GRINDING MACHINE-STEADYREST I Filed Jan. 24, 1955 2 Sheets-Sheet 2 4 3 Ola A [fl 2 15 WA LDJOYL United States Patent GRINDING MACHINE-STEADYREST Application January 24, 1955, Serial No. 483,475

3 Claims. (Cl. 51-103) The invention relates to grinding machines and more particularly to a work steadying rest for supporting and v steadying a work piece during grinding.

One object of the invention is to provide a simple and thoroughly practical steadyrest for a grinding machine. Another object of the invention is to provide a twobearing shoe type steadyrest having a pair of pivotally mounted steadyrest shoes one of which engages the work piece in a horizontal plane passing through the work axis and the other being arranged to engage the work piece from below at a position adjacent to the line of contact between the grinding wheel and the work piece being ground. Another object is to provide a two-bearing shoe steadyrest in which a single piston and cylinder is provided to actuate both of the pivotally mounted arms to move the shoes into steadying engagement with the Work piece and to maintain them in position during a grinding operation. Another object of the invention is to provide a two-bearing shoe steadyrest with a single piston and cylinder actuated cam for swinging both of the shoes into and away from operative engagement with the work. Another object is to provide a multiple two-bearing shoe steadyrest each of which is provided with a pair of pivotally mounted work steadying shoes which are actuated by a cam mechanism controlled by a single piston and cylinder mechanism.

Other objects will be in part obvious or in part pointed out hereinafter.

In the accompanying drawings, in which is shown one of various possible embodiments of the mechanical features of this invention,

Fig. l is a front elevation of a multiple wheel grinding machine showing the multiple steadyrest;

Fig. 2 is a fragmentary vertical sectional view, on an enlarged scale, .through the grinding wheel feeding mechanism;

Fig. 3 is a fragmentary plan view, on an enlarged scale of the multiple steadyrest having parts broken away and shown in section;

Fig. 4 is a vertical sectional view, taken approximately on the line 44 of Fig. 3, through one of the steadyrests; and

Fig. 5 is a combined electric and hydraulic diagram of the wheel feed and steadyrest controls.

A multiple wheel grinding machine has been illustrated in the drawings comprising a base which supports a longitudinally movable Work table 11 on the usual fiatway 12 and V-way 13. The table 11 serves as a support for a headstock 14 having a headstock center 15 which may be driven by an electric motor 16 mounted on the upper surface of the headstock 14. The headstock center 15 serves as a support for the left hand end of a work piece 17 having a plurality of spaced portions thereon to be ground. The table 11 also supports a footstock 18 having a footstock center 19 which supports the right hand end of the work piece 17. r

A manually operable traversing mechanism is provided for traversing the work table 11 longitudinally to position Patented July 29, 1958 grinding wheels. A manually operable hand wheel 20 is provided for actuating the table traversing mechanism (not shown). This mechanism may be the well known traversing mechanism such as shown in the expired U. S. patent to C. H. Norton No. 762,838 dated June 14, 1904, to which reference may be had for details of disclosure not contained herein.

The base 1e also serves as a support for a transversely movable wheel slide 21 which is arranged to slide transversely on slideways (not shown) which are old and well known in the prior art. The wheel slide 21 supports a rotatable wheel spindle 22. The wheel spindle 22 is provided with a plurality of spaced grinding wheels 23, 23a, 23b, 23c and 23d, one wheel for each portion of the work piece to be ground. A driving motor 24 is mounted on the upper surface of the wheel slide 21. -The motor 24 is provided with a motor shaft having av multiple V-groove pulley 26 which is connected by multiple V-belts 27 with a multiple V-groove pulley 28 mounted on the right hand end of the wheel spindle 22 (Fig. 1). j I

A feeding mechanism is provided for imparting a transverse feeding movement to the wheel slide 21 and the grinding wheels 23. This mechanism may comprise a rotatable feed screw 30 (Fig. 2), the right hand end of which is rotatably supported in a slidably mounted sleeve 31. The left hand end of the feed screw 30 is slidably keyed within a sleeve 32 which is rotatably journalled in an anti-friction bearing 33. A feed'nut 34 meshes with or engages the feed screw 30 and is hand end of the sleeve 32. The shaft 36 carries a gear 37 at its left hand end which meshes with a gear38. The gear 38 is mounted on the right hand end of a rotatable shaft 39, the other end of which supports a gear 40 which meshes with a gear 41. The gear 41 is operatively connected to rotate with a manually operable feed Wheel 42. The feed wheel 42 is a conventional type feed Wheel such as is well known in the grinding art and includes a micrometer adjusting mechanism 43 for adjusting the position of a stop abutment 44 relative to the feed wheel 42. A feed pawl 45 is pivotally mounted on a stud 46 fastened to the front of the machine base 10. The feed pawl 45 is provided with an adjustably mounted screw 47 which is arranged to be engaged by a cam 48 carried by the stop abutment 44 when the feed wheel 42 is rotated in a counter-clockwise direction for imparting an infeeding movement to the wheel slide 21 and the grinding wheels 23. The feed pawl 45 is provided with a downwardly extending arm 49 which is provided with an adjustable screw which engages the actuating roller of a normally closed limit switch LS1, the function of which A power operated feeding mechanism is provided for imparting a rotary motion to the feed screw 30 comprismg a cylinder 50 which contains a slidably mounted piston 51. The upper surface of the piston 51' is pro vided with a rack bar 52 which meshes with a gear 53 mounted on a rotatable shaft 54. The shaft '54 is also provided with a gear 55 which meshes with the gear 40. It Will be readily apparent from the foregoing disclosure, that when fluid under pressure is admitted to the cylinder- 50 to cause the piston 51 to move toward the right (Fig. 5), a rotary motion will-be imparted to thefeed screw 30 to cause a forward feeding movement of the slide 21 and the grinding wheels 23.

wheel A power operated mechanism is provided for rapidly moving the wheel slide 21 to and from an operative position. This mechanism may comprise a cylinder 57 which is arranged in axial alignment with the sleeve 31 and the feed screw 30. The cylinder 57 contains a slidably mounted piston 58 which is connected by means of a piston rod 59 with the sleeve 31 so that when fluid under pressure is admitted to either end of the cylinder a rapid transverse feeding movement of the wheel slide 21 will be obtained. This feeding and rapid approaching mechanism has not been illustrated in detail since it is identical with that shown in the prior U. S. Patent to H. A. Silven No. 2,572,529, dated October 23, 1951, to which reference may be had for details of'disclosure not contained herein.

A work steadying rest is provided for steadying and supporting the work piece between centers during a grinding operation. This steadyrest may comprise a steadyrest base (Figs. 3 and 4) which is provided with a dove-tailed surface 66 which mates with a correspondingly shaped surface formed on a swivel table 11a mounted on top of the work table 11. A clamping block 67 is provided for clamping the steadyrest base 65 onto the swivel table 11a. An arm 68 is pivotally supported by a pair of axially aligned spaced opposed conically shaped set screws 69 which are supported by the base 65. The arm 68 is provided with an upwardly extending portion which supports an adjustable work steadying shoe 70 which is arranged to engage the work piece to be ground at a point substantially diametrically opposite the line of contact between the grinding wheel 23b and the work piece 17. The arm 68 is also provided with a horizontally extending arm 71.

A pivotally mounted arm is supported by a pair of axially aligned pivot screws 76. The upper end of the arm 75 is provided with an adjustable work steadying shoe 77 which is arranged to engage the lower surface of the work at a position adjacent to the line of contact between the grinding wheel and the work piece being ground. The arm 75 is provided with a horizontally extending arm 78. The arms 71 and 78 are provided with opposed plane surfaces 79 and 80. A compression spring 81 is provided between the arms 68 and 75 which is arranged to exert a pressure tending to maintain the arms 68 and 75 in inoperative positions. The steadyrest base 65 is provided with a rotatable shaft 82 having a cam 83 keyed thereon which is arranged to engage the plane surfaces 79 and 80 of the arms '71 and 78 respectively. In the position illustrated in Fig. 5, the cam 83 is positioned so that the plane surfaces 79 and 80 engage flat or plane faces on the cam 83 so that the compression of the spring 81 swings the arm 68 in a counter-clockwise direction and the arm 75 in a clockwise direction so that the work steadying shoes 70 and 77 are in inoperative positions as illustrated in Fig. 5.

When it is desired to move the Work steadying shoes 70 and 77 into operative supporting engagement with the work piece 17, the shaft 82 may be rotated in a clockwise direction to rotate the cam 83 thereby shifting the arm 68 in a clockwise direction and the arm 75 in a counter-clockwise direction to position the work steady shoes 70 and 77 in operative supporting engagement with the work piece 17.

A fluid pressure mechanism is provided for actuating the shaft 82 and the cam 83 comprising a cylinder 85 which contains a slidably mounted piston 86. The piston 86 is connected to the left hand end of a piston rod 87 (Fig. 4). An arm 88 is keyed onto the shaft 82 and is provided with a stud 89 at its upper end which supports a' roller 90. The roller 90 is arranged to ride in a verticalslot 91 formed in the side face of the piston rod 87.

When fluid under pressure is passed through a pipe 95 into a cylinder chamber 96, the piston 86 together with the piston rod 87 -will be moved toward the right piston 86 fluid within a cylinder chamber 97 may exhaust through a pipe 98.

A fluid pressure system is provided for supplying fluid under pressure to actuate the steadyrest comprising a motor driven fluid pump 100 which draws fluid through a pipe 101 from a reservoir 102 and passes fluid under pressure through a pipe 103. A relief valve 104 is provided in the pipe line 103 to facilitate exhausting excess fluid under pressure directly to the reservoir 102 so as to maintain a substantially uniform operating pressure within the fluid system.

A control valve 105 is provided for controlling the admission to and exhaust of fluid from the cylinder 85. The valve 105 is a piston type valve comprising a valve stem 106 having a plurality of spaced valve pistons 107, 108 and 109-formed integrally therewith to form spaced valve chambers 110, 111 and 112. A central passage 113 is provided to' connect the valve chambers 111 and 112. I11 the position of the valve 105 (Fig. 5) fluid under pressure from the pipe 103 passes through the valve chamber 111, through a pipe 114, through both a ball check valve 115 and a throttle valve 116, through the pipe 98 into the cylinder chamber 97 to move the valve piston 86-toward the left thereby shifting the steadyrest shoes 70 and 77 to inoperative positions.

The control valve 105 is normally held in a left hand end position by means of a compression spring 117. A

solenoid S1 is provided for shifting the valve stem 106 toward theright when energized. During this movement of the steadyrest shoes 70 and 77 to an operative position fluid within the cylinder chamber 96 exhausts through the pipe 95 into the valve chamber 112, through the central passage 113' into the valve chamber and exhausts through a pipe 118 into the reservoir 102.

It is desirable to rough grind the work piece to a predetermined extent before the steadyrest shoes are moved into an operative position. When an infeeding movement is initiated, the feed wheel 42 is rotated in a counterclockwise direction to cause an infeeding movement of the slide 21 and the grinding wheels 23 while the steadyrest shoes70 and 77 remain in inoperative positions out ofcontact with the work piece. After the grinding has proceeded to thedesired extent, the cam 48 engages the follower screw 47 and rocks the feed pawl 45 together with the downwardly extending arm 47 in a counter-clockwise direction thereby allowing the normally closed limit switch LS1 to close thereby closing circuit to energize the solenoid S1 to shift the valve stem 106 toward the right. When the valve stem 106 reaches its right hand end position, fluid under pressure from the pipe 103 enters the valve chamber 108 and passes through the pipe 95 into the cylinder chamber 96 to move the piston 86 toward the right thereby rocking the arm 88 together with the shaft 82 and the cam 83 in aclockwise direction to move the work steadying shoes 70 and 77 into operative supporting engagement with the work piece 17. During this movement fluid within the cylinder chamber 97 exhausts through the pipe 98, through the throttle valve 116, through the pipe 114 into the cylinder chamber 110 and exhausts through the pipe 118. By manipulation of the throttle valve 116, the rate of movement of the shoes into operative supporting engagement with the work piece may be readily controlled.

The work steadying shoes 70 and 77 are adjustably supported relative to the arms 68 and 75 respectively so that the shoes may be readily adjusted to accommodate work pieces of different diameters.

It may be desirable to employ a plurality of spaced steadyrests to provide an adequate steadying support for the work piece 17. As illustrated in Figs. 1 and 3, three steadyrests are shown each of which is substantially identical in construction except that only the center steadyrest is provided with the power actuating cylinder and associated pa-rts. As illustrated in Fig. 3 a steadyrest frame 65a is mounted on the swivel table 11a. This steadyrest is provided with a pivotally mounted arm 68a supported by a pair of opposed pivot screws 76a. The arm 68a is provided with an adjustably mounted work engaging shoe 70a. The steadyrest base 65a also supports a pivotally mounted arm 75a having an adjustably mounted steadyrest shoe 77a. The arm 75a is pivotally supported by a pair of opposed aligned pivot screws 69a carried by the frame 65a. The steadyrest base 65a is provided with a rotatable shaft 82a which is arranged in axial alignment with the shaft 82 of the steadyrest base 65. The shafts S2 and 82a are connected by a coupling 119. The shaft 82a is provided with a cam 83a for actuating the steadyrest shoes 70a and 77a.

A similar steadyrest base 65b is mounted on the swivel table 110. and is provided with a pivotally mounted arm 68a which supports an adjustably mounted work steadying shoe 70b. The arm 68a is pivotally supported by a pair of axially aligned opposed pivot screws 76b carried by the base 65b. The base 65b also supports a pivotally mounted arm 7511 which is provided with an adjustably mounted work steadying shoe 77b. The-arm 75b is pivotally supported by a pair of opposed axially aligned pivot screws 6% supported by the steadyrest base 65b. The steadyrest base 65b is provided with a rotatably mounted actuating shaft 82b which is arranged in axial alignment with the shaft 82. The shaft 82 is connected to the shaft 82b by means of a coupling 120. The shaft 82b is provided with a cam 83b for actuating the steadyrest shoes 70b and 77b. It Will be readily apparent from the foregoing disclosure that movement of the piston 86 (Fig. 4) will be imparted through the roller 90 and the arm 88 to import a rotary motion to the shaft 82 which is transmitted through the couplings 119 and 120 to impart a rotary motion to the shafts 82a and 82b so that the work steadying shoes on all of the steadyrests are simultaneously moved into operative supporting engagement with the work piece to be ground.

The operation of this improved steadyrest will be readily apparent from the foregoing disclosure. Assuming all of the adjustments to have been previously made, a work piece 17 having spaced portions to be ground is mounted in position on the headstock center 15 and footstock center 19 after which the motors 16 and 24 are started. The pump 100 is started and an infeeding movement of the grinding wheel is imparted either manually or by power rotating the feed screw to advance the Wheel slide 21 and the grinding Wheels 23 to grind the spaced portions on the Work piece 17. The grinding is continued to a predetermined extent until the cam 48 engaging the screw 47 rocks the pawl 45 and the arm 49 in a counter-clockwise direction thereby allowing the limit switchLSl to close so as to energize the solenoid S1. The closing of the solenoid S1 shifts the valve stem 106 toward the right so that fluid under pressure is passed through the pipe 95 into the cylinder chamber 96 to cause the piston 86 (Figs. 4 and to move toward the right so as to impart a clockwise motion to the arm 88 which serves to rotate the shaft 8282a-82b thereby rotating the cams 8383a83b to move the work steadying shoes simultaneously into operative supporting engagement with the work piece where they are maintained during the grinding operation. After the grinding operation has been completed, the feed wheel 42 is rotated in a clockwise direction to cause the wheel slide 21 together with the grinding wheels 23 to move to a rearward or inoperative position. During clockwise rotation of the feed wheel 42, the cam 48 allows the pawl 45 together with the arm 49 to move in a clockwise direction under the influence of a tension spring until the limit switch LS1 opens thereby deenergizing the solenoid S1 which serves to change the direction of flow of fluid to the steadyrest cylinder. automatically and simultaneously withdraw all of the steadyrest shoes from operative engagement with the work piece 17.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiments above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrated and not in a limiting sense.

I claim:

1. In a grinding machine having a rotatable work support and a transversely movable rotatable grinding wheel, a feeding mechanism to impart a transverse feeding movement to the grinding wheel, a steadyrest having a pivotally mounted arm, an adjustable steadyrest shoe thereon arranged to swing in a substantially horizontal direction, a second pivotally mounted arm, an adjustable steadyrest shoe thereon arranged to engage the underside of the work piece being ground, means normally to maintain said shoes in an inoperative position, means including a rotatable cam in engagement with both of said pivotally mounted arms simultaneously to swing said arms to move said shoes into operative engagement with a work piece being ground, and means actuated by and in timed relation with said feeding mechanism to actuate said cam to cause said shoes to move into an operative position when the grinding wheel has advanced to a predetermined extent.

2. In a grinding machine as claimed in claim 1, in combination with the parts and features therein specified of a plurality of spaced steadyrests each having a pair of pivotally mounted work steadying shoes, a rotatable shaft on each of said steadyrests, operative connections between said shafts, a cam on each of said shafts for actuating a pair of said shoes, and means including a single fluid motor operatively connected to impart a rotary motion to all of said shafts and cams simultaneously to move all of said shoes into operative engagement with a work piece being ground.

3. In a grinding machine as claimed in claim 1, in combination with the parts and features therein specified of a plurality of spaced steadyrests each having a pair of pivotally mounted work steadying shoes, a rotatable shaft on each of said steadyrests which are arranged in axial alignment with each other, operative driving connections between said shafts, a cam on each of said shafts each of which is arranged to actuate a pair of said shoes, a fluid motor on one of said steadyrests and operative connections between said motor and said shafts whereby movement of said motor imparts a simultaneous rotary motion to said shafts and cams simultaneously to move all of said shoes into operative supporting engagement with a work piece.

References Cited in the file of this patent UNITED STATES PATENTS 1,961,091 Smith et al. May 29, 1934 2,141,596 Crompton Dec. 27, 1938 2.160378 Balsiger May 30, 1939 2,399,608 Silven Apr. 30, 1946 2,419,170 Silven Apr. 15, 1947 2,567,620 Silven Sept. 11, 1951 2,693,060 Mader et a1. Nov. 2, 1954 2,693,062 Silven et al. Nov. 2, 1954 2,723,504 Alvord Nov. 15, 1955 FOREIGN PATENTS 850,861 Germany Sept. 29, 1952 912,061 Germany May 24, 1954

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