US2029510A

US2029510A - Hydraulic ball race grinder

Info

Publication number: US2029510A
Application number: US389492A
Authority: US
Inventors: Amos P Steiner; Edgar P Wine; Harold E Balsiger
Original assignee: Landis Tool Co
Current assignee: Landis Tool Co
Priority date: 1929-08-30
Filing date: 1929-08-30
Publication date: 1936-02-04
Anticipated expiration: 1953-02-04

Description

Filed Aug. 30, 1929 6 Sheets-Sheet l INVENTORS Amos P S'fcl'ner.

B Y Edgar-P Mine.

Harold E. Sal s/yer: ,l-TTORNEY Feb. 4, 1936.

A. P. STEINER ET AL HYDRAULIC BALL'RACE GRINDER Filed Aug. 30, 1929 6 Sheets-Sheet 2 INVENTORS Hmos P S/einen BY I Edgar P Wine.

W f- 50/31 er.

' A TTORNEY Feb. 4, 1936. A. P. ST EINER ET AL HYDRAULIC BALL RACE GRINDER Filed Aug. 30, 1929 6 Sheets-Sheet 3 uuu I-I-unmmu A TTORNE Y Feb. 4, 1936.

A. P. STEINER El AL HYDRAULIC BALL RACE GRINDER Filed Aug. 30, 1929 6 Sheets-Sheet 4 IN VEN TORs x Amos 1'? sveinei; L B Y Edgar Mae Hero/J 5d [J] 9 er.

r ?,,A TTORNEY I 1936 A. P. STEINER ET AL HYDRAULIC BALL RACE GRINDER Filed Aug. 30, 1929 6 Sheets-Sheet 5 Sank . Rf dY I I R Q 5 P mwwmm AEH Feb. 4, 1936. A. P-.-, STEINER ET AL 2,029,510

HYDRAULIC BALL RACE GRINDER Filed Aug. 30, 1929 6 Sheets-Sheet 6 grm'nfow Amod PSieiner j Edgar]? M/z'ne fiamld EBaldiger Patented Feb. 4, 1936 UNITED STATES HYDRAULIC BALL RACE GRINDER Amos P. Steiner, Edgar P. Wine, and Harold E. Balsiger, Waynesboro, Pa., assignors to Landis Tool Company, Waynesboro, Pa., a corporation of Pennsylvania Application August 30, 1929, Serial No. 389,492

22 Claims.

Our invention relates to semi-automatic hydraulically operated machines for grinding the bearing surfaces of ball races and is an improvement on our co-pending application Ser. No. 401,500 filed October 22, 1929 for Hydraulic ball race grinders.

Among the objects of the invention are to provide a simplified mechanism for operating the wheel base, to provide means to stop the grinding operatic-nautomatically when a piece of work has been ground to size and return'the various mechanisms to inoperative position, to provide positive slow-down means for the wheel base, to provide control means and timing means for the various mechanisms and to provide a new and improved work sizing device.

Referring to the accompanying drawings, which are made a part hereof and on which similar reference characters indicate similar parts.

Figure 1 is a front elevation of the machine,

Figure 2 is a plan view of a part of the work head oscillating mechanism,

Figure 3 a front elevation of the wheel base and automatic wheel feed mechanism,

Figure 4 is a sectional front elevation of the driving mechanism for the automatic wheel feed, I

figure 5 is a section on line 5-5 of Figure 3, showing the automatic feed screws and the valve shifting plunger,

Figure 6 is a right hand elevation of the wheel base and carriage,

Figure '7 is a plan view of the rear end of the wheel base feed showing a part of the wheel carriage control,

Figure 8 is a somewhat diagrammatic view in section showing the relation of the valves and fluid connections to the various mechanisms throughout the machine,

Figure 9 is a diagrammatic view of circuits and devices controlled by the sizing device,

Figure 10, a vertical section similar to Figure 6 to show in full lines the various relationships to each other of the piston rod, the carriage gears and shaft,

Figure 11, a section on line II--II of Figure 10,

Figure 12 is a view in elevation partly in section of the sizing device,

' Figure 13, a detail view of a crank for resetting the sizing device,

Figure 14, a plan view of the lower end of the sizing device,

Figure 15, a section on line I5-I5 of Figure 14, and

Figure 16, a section of the motor for operating the sizing device.

In the drawings reference character I0 indicates the bed of a grinding machine having a wheel carriage I I mounted to move longitudinally of the bed. A wheel base I2 is mounted upon the carriage II to move transversely of the carriage, the wheel base carrying a grinding wheel I3 suitably mounted thereon which grinding wheel is driven by means of a motor I4. The wheel base I2 may be manually adjusted transversely of the carriage II by means of a hand wheel I5. A bracket I6 is mounted on the bed I0 so as to be oscillated about a shaft I1 by means of a motor I8. stock I9 upon which the work is carried. The head stock I9 may be adjusted transversely of the bracket I6 on a slide 2I and may be adjusted longitudinally of the bracket I6 by means of an adjusting screw 22. The head stock may be driven by means of a motor 23 through any suitable driving connection enclosed in a housing 24. The head stock also carries a. sizing device 25 mounted thereon which sizing device comprises an arm 26 which carries a diamond 21 in its lower end which diamond is adapted to be positioned within the work to engage the work piece 26. The sizing device is movable into and out of operative positions by means of a motor 28. The

sizing device is positioned and operated so as 'to' require a minimum of space for its movement into and out of operative position. The sizing device 25 has a depending bracket 26 upon which is mounted a lever I which is pivoted at its lower end to a bent out portion of the bracket 26 by means of straps or hinges I6I, I62, best shown in detail in Figures 14 and 15. A suitable contacting element 21 is seated in the bent end portion I64 of the lever I60. The upper end of the lever I60 is free to swing and is moved in a clockwise direction by means of a spring I65 which is attached to a lug I66 on an arm I61. The arm I61 is attached by means of a bracket I68 to the upper end of the lever I60. The upper side of the arm I61 has a lug I69 through which passes a bolt I10. A spring I1I surrounds the bolt and is confined between the lug' I69 and the end of the lever I60. The side of the lever I60 opposite the spring has secured thereon a sleeve I12 through which the end of the bolt I10 is threaded. By means of the bolt I10 the angular position of the arm I61 with respect to the lever I60 may be adjusted. Triggers I13 and I14 are pivoted to the side of the casing of the sizing device 25 and their ends are adapted to engage the sharp edge 'of the upper portion of the lug I69. The triggers are each moved in a clockwise direction by means of springs I15. The triggers I13 and I14 carry arms I16 and I11 on their opposite ends. Means for resetting the triggers against the tension of the springs I15 consists of a crank I18 attached to the outer end of a shaft I19. The shaft carries an arm I which is adapted to engage a lug I8I on the end of the arm I 61 to swing the lever I60 counterclockwise. The shaft also carries a short arm I82 having a pin I83 which engages lugs I84 on The bracket I6 carries a head .the triggers I13 and I14 to move the triggers counterclockwise to reset the sizing device. The arm I80 is rotated in a counterclockwise direction by means of a spring I85. A pin I86 limits the action of the spring I85. Arm I11 serves to close

contacts

86 and 81 and arm I16 controls contacts H4 and 5' shown in Figure 9. No novelty resides in the switch and hence they are not shown as any suitable make and break switch may be used. The motor 28 is of the oscillating type and consists of a casing I81 having a shaft I88 mounted therein with blades I88 mounted on the shaft. The opposite chambers of the motor are divided by partition walls I80. Pressure fluid lines MI and I42 are connected to the motor chambers. The outer end of the shaft I88 has attached thereto a link I8I which is attached at its other end to the housing of the sizing device.

In operation the sizing device is moved to position the feeler in contact with the work which is to be ground. The triggers I13 and I14 are positioned so that they rest upon the top of the lug I68. When the work has been reduced nearly to finished size and the contacting element 21 moves in, it permits the lever I 68 to be rotated in a clockwise direction until the trigger I14 drops off the lug I68. This closes

contacts

86 and 81. When the work has been reduced to finished size the lever I60 moves to permit-trigger I13 to drop oil lug I68 so that contacts H4 and H5 are brought together. The sizing device controls a number of mechanisms including means for slowing down the rate of oscillation of the work head as the grinding nears the finished size, stops oscillation of the work when it is ground to size, stops the automatic feeding of the grinding wheel toward the work, removes the sizing device from the work, and returns the wheel base and the carriage to inoperative position, all of which mechanisms will be later described more in detail.

The wheel base and wheel carriage mechanism The means for feeding the carriage longitudinally of the bed of the machine and formoving the wheel base transversely to move the grinding wheel into and out of grinding position will now be described. The means for moving the carriage longitudinally of the bed of the machine comprises a cylinder 28 formed within the carriage II and having a piston 36 movable therein to which piston is attached a piston rod 3| which is secured to a bracket 32 on the bed of the machine. It will be seen therefore that the cylinder moves and that the piston remains stationary, being fixed to the bed of the machine. The cylinder 28 has a fluid port 33 at one end and port 34 at the other end, and a port 35 spaced from the port 34.

Fluid lines

36 and 31 are connected to the port 33 and ports 34 and 35 respectively. The ports 34 and 35 are connected through a spring pressed check valve 38, the valve being provided with a restricted opening to permit fluid to flow freely into the cylinder 28 through port 34 but to restrict its fiow out of the cylinder through port 34, the purpose of which is to slow down movement of the wheel carriage after the piston has closed off the port 35. The wheel carriage II is chambered also to provide a cylinder 38 in which a piston 40 operates. A piston rod 4I connects the piston to a bracket 12 on the wheel base I2. Fluid port 42 at one end of the cylinder and ports 43 and 44 at the other end of the cylinder provide for the passage of fiuid to and from the cylinder. A fluid line 45 is connected to port 42 and a fluid line 46 to ports 43 and 44. An adjustable check valve 41 controls passage of fluid from port 43 to line 46, this valve being spring pressed to permit fluid to freely flow into the line 43 and to restrict its flow from the port 43 to line 46 as was described with respect to ports 34 and 35.

In order to bring the grinding wheel into position it is necessary first to move the wheel base back so that the grinding wheel I3 may enter the work piece and then to move the wheel carriage axially of the work to position the grinding wheel 'within the work. This is accomplished by using a common direction valve 48, which, as shown in Fig. 8, is in positon to admit fluid from pump 56 through line 48, valve chamber 48 and out through port 5|, needle valve 52 through line 36 to cylinder 28 and through branch 53, valve chamber 54 and line 45 to port 42 in cylinder 38. In order that the grinding wheel may be positioned within the work before the wheel base moves the grinding wheel to grinding position in contact with the work passage through valve chamber 54 is delayed. This is accomplished by a valve 55 which is operated by a lever 56, one end of which comes into engagement with an abutment 51 on the bed of the machine as the grinding wheel reaches almost the end of its travel axially into the work to open communicalion between

line

53 and 45. A spring pressed K check valve 58 permits return of fluid freely through line 45 to line 53. As previously described the wheel carriage will move longitudina ly of the bed until it nears the end of its travel at which time piston 30 will close off port 35 whereby travel of the carriage is slowed down due to the restriction at 38 which permits fluid to pass slowly from port 34 into the line 31. The Wheel base likewise moves radially until it nears grinding position at which its movement is checked by the check valve 41 to permit slow travel of the wheel base to grinding position.

The valve 55 is biased toward position to close off the

line

53 and 45 by means of a spring 58. To return the carriage and wheel base to inoperative position valve BI is shifted by mechanism later to be described so that pressure fluid is directed through the line 60. Fluid then passes from line 48 through valve chamber 48 out through the port 62 to the line 60. Fluid pas:es from the line through the valve chamber 64 and line 46, check valve 41 and port 43 below the piston 40 to move the wheel base to the rear and this movement will be gradual at first until the piston 40 passes port 44 at which time fluid may enter the cylinder 38 through the port 44 to freely move the wheel base to the rear. The piston rod H has a collar 65 which strikes a lever 66 as the carriage nears its retracted position to shift a valve 61 to admit fluid from the line 60 through the valve chamber 64 directly to the line 31. This will freely admit fluid to the right of the piston 30 at first slowly through port 34 until port 35 is opened and then freely to retract the wheel carriage rapidly to the right.

The wheel feed mechanism consists of manual and automatic means for feeding the wheel into the work. The manual feed consists of the hand wheel I5 mounted on a shaft 68. A gear 68 is mounted inside the wheel base on the shaft and is keyed to the shaft so as to slide axially of the shaft. The gear 68 meshes with a gear 10 on the piston rod H which is screw-threaded at its outer end. The piston rod M is threaded through a bracket 12 depending from the wheel base I2. I

Rotation of the shaft 68 causes screw shaft 4| to rotate and move the bracket 12 and hence move the wheel base I2 transversely of the carriage II. The automatic wheel feed consists of the wheel base cylinder 39 and the piston rod 4| which have been described above and which lfaurnish the motive power for operating the wheel ase.

The wheel base I2 moves forward rapidly under hydraulic pressure until the slow-down mechanism previously described catches it and a front extension of the piston rod 4| strikes a lead screw 13. The front end of the rod 4| has an inclined surface 14 which engages a corresponding inclined surface 15 on a plunger 16 and depresses the plunger against the action of a compression spring 11. The lower end of the plunger engages an arm 18 which acts through shaft 19 to rotate an arm 80. By means of a link 8| the arm 80 rocks a lever 82 secured to a shaft 83. To the other end of the shaft is secured a lever 83' which engages a spool 84 on a valve stem 85. The valve stem 85 has

valve disks

86 and 66 in a valve chamber and a spring 85' is biased to hold the valves in closed position. By means of the lever 82 the valve is shifted against the tension of the spring to admit pressure fluid through the port 81 to move a piston 89 to the right. Pressure fluid entering this side of the piston is controlled by an adjustable needle valve 88. The piston 89 has a piston rod 90 to the outer end of which is attached a bar 9| having rack teeth on its upper side. These teeth mesh with a gear segment 92 which is mounted on the end of the lead screw 13. When the piston 89 moves from left to right the lead screw 13 is rotated to allow the wheel base to move forward. The speed of feed is determined by adjustment of the needle valve 88. Pressure fluid is supplied to the valve 86 from pump 50 through a line 1| and a starting and stopping valve 94 which is controlled by a solenoid 95. When the solenoid 95 is energized by.movement of the sizing device which closes contacts 96 and 91 the port 96 is closed by the valve disk 94. By mechanism above described contacts 96 and 91 are brought together by the sizing device just shortly before the work is reduced to'its finished size. When the wheel base I2 is retracted on completion of the work the plunger 16 is released and the spring 85 shifts valve 86 to the position to return the piston 89 and the lead screw 13 to the starting position.

' As shown in Figure 4 the supply of pressure fluid through port 81' is not restricted when directed to this side of the piston 89. When the valve 86' is shifted to open ports 81' to pressure fluid line 96 the screw 13 is quickly rotated to starting position. 91 indicates an exhaust line to a reservoir in the bed of the machine.

The valve for controlling oscillation of the head stock is shown in diagrammatic'form as a whole at 98. This valve consists of a piston rod 99 having valve disks I00, IOI, I02, I03, I04, I05 and I06 spaced along it. A compression spring I01 in the bottom of the valve casing presses against the lower side of the disk I06 to hold the valve disks normally in their elevated position. The disks may be manually moved in the valve chamber by means of a lever I08, or they may be moved down automatically by means of a solenoid I09. The solenoid I09 controls fluid passages H0 ,and III which admit pressure fluid above the piston l I2 to move the valve 99 down against the tension of compression spring I01. The disks are moved down when solenoid I09 is energized upon closing of contacts H4, H5. These contacts are closed by suitable mechanism in the sizing device after the work has been reduced to correct size. The control valve just described controls the operation of the motor I6 which oscillates stem H6. The shaft II8 has an arm |2I on its upper end which is engaged by dogs I22 on a ring I23 secured to and surrounding the oscillating frame I6. When the frame is oscillated the shaft H8 is rocked to reciprocate the piston II6 to open fluid ports to opposite sides of the motor I8. When the valve 99 and the valve II6 are inthe positions shown in Fig. 8 pressure fluid may pass from the source of pressure 49 through the valve 48 through line I to the valve chamber out through line I26 through valve I24, line I21 to the valve chamber, in the valve H6 and out through line I28. to the oscillating motor I8.

Exhaust fluid may pass from the motor through line I29, valve chamber of valve 6 and out through exhaust line I to a reservoir in the base of the machine. The oscillating motor will be caused to make one stroke at the end of which valve I I6 will be shifted to the left to allow presin valve 98 to the line I32 and to the exhaust line I33. Shifting of the valve I I6 will therefore reverse the stroke of the oscillating motor to cause continuous oscillation of the bracket I6 carrying the head stock on which the work is supported. When the work nears completion and contacts 96, 91 are brought together by the sizing device, the solenoid I34 is energized to move the valve stem in valve chamber I24 to restrict the flow of fluid from the line I26 to line I21 to cause the oscillating motor to slow down. When the Work has been finished contacts H4 and H5 are brought together to energize solenoid I09 to open communication between ports H0 and III to admit pressure fluid above piston II2 to pull down valve stem 99 toclose oif communication between pressure fluid line I25 and line I26 but to open exhaust lines I and I38 to line I32 so that both sides of the oscillating motor I8 are open to the exhaust line so that the head stock scribed.

The operator may lift the lever I08 to an intermediate position shown in dotted circle I31. When in this position valve disk I00 closes ofi pressure line I26 so as to stop oscillation of the motor I8. Valve disk I02 moves down to open communication between pressure line I25 and line I38. through line'I39 and needle valve I40. Pressure fluid then passes through line I25 to the motor I8 to move it to a position to swing the work toward the front of the machine when it maybe easily removed. When the valve stem is moved to this position disk I06 closes communication between line I38 and I32. Valve stem 99 is connected to valve 6| by a pivoted lever I53 so that depressing the valve stem 99 moves disk 6| to close port 5| and open port 62.

The sizing device itself is operated by a fluid motor 28 supplied by fluid lines I 4| and I42. Admission of pressure fluid from line I43 is controlled by a valve I44. This valve is operated by a solenoid I45. When the solenoid is energized the valve is opened to admit fluid to the motor 28 to swing the sizing device free from the work. The solenoid is in circuit with contacts H4 and H5 which are closed when the work is reduced to finished size. Line I54 is an exhaust to a fluid reservoir in the base of the machine.

The operation of the device is as follows: Assume the parts to be in position in which they are shown diagrammatically in Fig. 8, in this position the grinding wheel is within the work and is in working position to grind the work and the sizing device is positioned within the work. As the stock is removed within the work the sizing device follows it until the work is nearly finished 'to size, at which time mechanism within the sizing device closes contacts 96 and 91. This closes circuit through lines I49, I50, I48, solenoid 95, lines I41, and I 5| to close circuit with the battery I52. This first energizes solenoid 95 to move the valve 94 to close fluid line 96 to cut oif fluid to the motor 89. This stops movement of the wheel base toward the work and at the same time solenoid I34 is energized to move the valve I24 to restrict the fiow of fluid through the line I21 to slow down the oscillating motor I8. The machine continues to grind until the work is reduced to its finished size at which time contacts H4 and H5 are brought together to energize solenoid I09. This opens communication between pressure fluid lines III! and I II to admit pressure fluid above piston II 2 to move the valve stem 99 against the tension of the spring I01. This causes valve disk I00 to shut off fluid line I26 to stop oscillation of the motor I8. Fluid, however, may exhaust from the motor so that it may be freely manually moved. As the valve stem 99 is drawn down lever I53 is rocked on its pivot to move the valve 6| forward of its position as shown in Fig. 8 to close communication between fluid line 49 and port 5| and to open communication with port 62. Pressure fluid then first flows through line 60 to valve 64, line 46, check valve 41 and port 43 to the rear of the piston 40 to withdraw the wheel base to move the grinding wheel out of contact with the work. As soon as the piston 40 has cleared port 44 fluid freely flows through this port to quickly withdraw the wheel base. After the wheel base has reached its rear position the disk 65 rocks the lever 66 to shift valve 61 to open communication between

lines

60 and 31. This delivers pressure fluid through check valve 38 into port 34 at the right of piston to begin slow movement of the wheel carriage to the right. As soon as the carriage has moved far enough to clear the port pressure fluid is rapidly delivered to the cylinder 29 and the wheel carriage is rapidly withdrawn to the rear.

As the wheel base begins its withdrawal movement the tapered edge 14 on the piston 4I allows the plunger 15 to be moved forward by the spring 11. This allows the rockarm 18 to move up to shift valve 86 to close port 81' to allow pressure fluid to enter to the right of the piston to shift the abutting screw 13 to position it in the path of the wheel carriage for the next grinding operation. As the work reached its finished size closing contacts H4 and II 5 also closed a circuit through line I55, solenoid I45, line I5I to energize this solenoid to cause it to operate valve I44 to admit pressure fluid from the line I43 to the line I to the motor 28, to move the sizing device out of contact with the work.

It will be obvious to those skilled in the art that various changes may be made in our device without departing from the spirit of the invention and therefore we do not limit ourselves to what is shown in the drawings and described in the specification but only as indicated in the appended claims.

Having thus fully described our said invention, what we claim as new and desire to secure by Letters Patent, is:

1. A machine for grinding ball races coinprising a bed, a work carrier mounted to oscillate on said bed, a wheel carriage slidably mounted for longitudinal movement on said bed, a wheel base slidably mounted for transverse movement on said carriage, a grinding wheel rotatably mounted on said wheel base, a source of pressure fluid, fluid pressure means to move said carriage and said wheel base rapidly into grinding position, and positive acting means to slow the wheel base down to grinding speed, substantially as set forth.

2. A grinding machine comprising a bed, a wheel carriage mounted on said bed, a. wheel base mounted on said wheel carriage, a fluid motor to move said wheel carriage longitudinally of the base, a second fluid motor to move said wheel base transversely of the wheel carriage, and interconnected means controlling operation of said motors, said means causing operation of the first-named motor to move said wheel base forward to grinding position and then to operate said second motor to move the grinding wheel to contact with the work and pressure fluid operated means for determining the speed with which the grinding wheel is fed into the work by the said second motor, substantially as set forth.

3. A grinding machine comprising a bed, a wheel carriage mounted on said bed, a wheel base mounted on said wheel carriage, a fluid motor to move said wheel carriage longitudinally of the base, a second fluid motor to move said wheel base transversely of the wheel carriage pressure fluid means for controlling the speed with which the second fiuid motor moves the wheel base during grinding of the work, interconnected means controlling operation of said motors, said means operating to withdraw the grinding wheel from contact with the work and then to operate the second fluid motor to withdraw the grinding wheel out of grinding position with the work,

substantially as set forth.

4. A grinding machine comprising a bed, a work carrier mounted to oscillate upon the bed, a grinding wheel base, a grinding wheel rotatably mounted in the base, a sizing device mounted on the work carrier and having means adapted to move it to engage the surface of the work, and a circuit controlled by said sizing device adapted when closed to stop feeding movement of the grinding wheel toward the work and to reduce the rate of oscillation of the work head at a predetermined point in the grinding operation, substantially as set forth.

5. A grinding wheel comprising a bed, a work carrier mounted on said bed, means for oscillating the work carrier, a grinding wheel base, a grinding wheel mounted in the base, a sizing device mounted on the work carrier and adapted to engage the surface of the work, a circuit in said sizing device adapted to be closed by the sizing device when the feeding movement of the grinding wheel reaches a predetermined point, the said circuit controlling means to reduce the rate of oscillation of the work head, and a second circuit in said sizing device adapted to be closed by the sizing device at the completion of the work, this circuit controlling means to stop oscillation of the work carrier and rotation of the work and to move the grinding wheel to inoperative position, substantially as set forth.

6. A grinding machine comprising a bed, a work carrier mounted upon said bed, means for oscillating the work carrier, a grinding wheel support, a grinding wheel rotatably mounted on the support, a sizing device mounted on the work carrier and adapted to close a circuit to stop feeding movement of the grinding wheel and reduce the rate of oscillation of the work at a predetermined point in the grinding operation, and means controlled by said sizing device for stopping feeding movement of the grinding wheel and oscillation of the work, and means for stopping oscillation of the work carrier at a position in which the work may be freely accessible when the oscillating means is stopped, substantially as set forth.

7. A grinding machine comprising a bed, a work support and a grinding wheel support, the grinding wheel support comprising a. carriage movable longitudinally of the bed and a wheel base movable transversely of the bed, hydraulically operated means for moving the wheel carriage toward the work and the wheel base to a grindingposition, means for timing operation of the said hydraulic means whereby in moving into operative position the wheel carriage will first move approximately to the limit of its travel and then the wheel feed will be moved to position the grinding wheel in grinding position and a hydraulically operated abutment for controlling the rate of feed of said wheel into said work, substantially as set forth.

8. A ball race grinder comprising a bed, a work support, means for oscillating the work support, a grinding wheel support, the grinding wheel support comprising a carriage movable longitudinally of the bed, means for movingthe carriage comprising a cylinder in said carriage and having a piston rod movable in said cylinder and secured to the said bed, a' second cylinder in said carriage having a piston rod secured to the said wheel base, and a valve controlling motive fluid to the said cylinders, means associated with said cylinders for delivering fluid first to move the carriage forward to position the grinding wheel within the work and then to move the wheel ,base forward to position the grinding wheel in contact with the work, substantially as set forth.

9. A ball race grinding machine comprising a bed, a work support, means for oscillating the work support, a grinding wheel support, the

grinding wheel support. comprising a carriage movable longitudinally of the bed and a wheel base movable transversely of the bed, means for moving the carriage comprising a cylinder in said carriage having a piston rod movable therein and secured to the said bed, means for moving the wheel base comprising a cylinder in the said wheel carriage having a piston rod movable therein and secured to the said wheel base, pressure fluid lines to the said cylinders, a valve for controlling flow of fluid through said lines, restricted valves in said lines arranged so as to deliver fluid to withdraw the wheel base to move the grinding wheel out of contact with the work and then to move the wheel carriage to withdraw the grinding wheel out of the work, substantially as set forth.

10. A ball race grinding machine comprising a bed, a work support, means for oscillating the work support, a grinding wheel support, the grinding wheel support comprising a carriage movable longitudinally of the bed and a wheel base movable transversely of the bed, means for moving the carriage comprising a cylinder in said carriage having a piston rod movable therein and. secured to the said bed, means for moving the wheel base comprising a cylinder in the said wheel carriage having a piston rod movable therein and secured to the said wheel base, pressure fluid lines to the said cylinders, a valve for controlling flow of fluid through said lines, restricted valves in said lines arranged so as to deliver fluid to withdraw the wheel base to move the 'grlnding' wheel out of contact with the work and then to move the wheel carriage to withdraw the grinding wheel out of the work, and a sizing device controlling operation of said valve to withdraw thegrinding wheel from the work when the work has been reduced in size, substantially as set forth.

11. A grinding machine comprising a bed, a work holding element, a grinding element, a carriage mounted for longitudinal movement on said of said carriage to bring the grinding element and the work into contacting relationship and additional pressure fluid means for controlling the transverse movement of said base as the grinding element contacts with the work.

12. A grinding machine comprising a bed, a work support and a grinding wheel support, one

' of said supports comprising a carriage movable longitudinally of the bed and a base movable transversely of the bed, hydraulically operated means for moving the carriage toward the other support and the base to a grinding position, means for timing operation of the said hydraulic means whereby in moving into operative position the carriage will first move approximately to the limit of its travel and then the base will be moved to grinding position and a hydraulically operated abutment for controlling the rate of feed of said base for the grinding action, substantially as set forth.

13. A grinding machine including a bed, a grinding wheel unit, a work holdin unit supported by the bed in substantial alignment with the axis of the grinding wheel, hydraulic means for shifting one of said units in the direction of the grinding wheel axis for presentation of a work piece in circumscribing relation to the grinding wheel, additional hydraulic means for shifting said unit in a direction at right angles to the direction of said first movement for effecting the grinding contact of the wheel and the work piece, a grinding determinator, and means controlled by movement of the determinator for reversing the aforesaid movements of. said units.

14. A grinding machine comprising a bed, a work holding element, a grinding element, a carriage mounted for longitudinal movement on said bed, a base supporting one of said elements and mounted for movement on said carriage, a fluid pressure m,lotor adapted to move said carriage longitudina ly of said bed, a fluid pressure motor adapted to move said base transversely of said carriage and interconnected means controlling the operation of said motors, said means causing operation of said first motor to move said carriage forward to telescoping relationship of the grinding element and the work and then to cause said second motor to move said base transversely of said carriage to bring the grinding element and the work into contacting relationship, and additional pressure fluid means for controlling the transverse movement of said base as the grinding element contacts with the work,

15. A grinding machine comprising a bed, a work holding element, a grinding element, a carriage mounted for longitudinal movement on said bed, a base supporting one of said elements and mounted for movement on said carriage, a fluid pressure motor adapted to move said carriage longitudinally of said bed, a fluid pressure motor adapted to move said base transversely of said carriage and interconnected means controlling the operation of said motors, said means causing operation of said first motor to move said carriage forward to telescoping relationship of the grinding element and the work and then to cause said second motor to move said base transversely of said carriage to bring the grinding element and the work into contacting relationship, and hydraulically operated means for controlling cross feed movement.

16. A grinding machine comprising a bed, a Work holding element, a grinding element, a carriage mounted for longitudinal movement on said bed, a base supporting one of said elements and mounted for movement on said carriage, a fluid pressure motor adapted to move said carriage longitudinally of said bed, a fluid pressure motor adapted to move said base transversely of said carriage and means controlling the operation of said motors, said means causing'operation of said first motor to move said carriage in one direction and then to cause said motor to move said base in another direction at right angles to the first movement to bring the grinding element and the work into contacting relationship, and fluid operating means for controlling further transverse movement of said base.

17. A grinding machine comprising a bed, a work holding element, a carriage mounted for longitudinal movement on said bed, a base mounted for movement on said carriage, a grinding element mounted on said base, a fluid motor for moving said carriage longitudinally of said bed, a fluid motor for moving said base transversely of said carriage, interconnected means controlling the operation of said motors, said means causing operation of said first motor to move said carriage forward to move the grinding element within the work and then to cause said second motor to move said base ransversely of said carriage to bring the grinding element into grinding contact with the work, and pressure fluid means for controlling the feeding movement of the grinding element into the work.

18. A grinding machine comprising a bed, a work holding element, a grinding element, a carriage mounted for longitudinal movement on said bed, a base supporting one of said elements and mounted for movement-on said carriage, a fluid pressure motor adapted to move said carriage in both directions longitudinally of said bed, a fluid pressure motor adapted to move said base in both directions transversely of said carriage and interconnected means controlling the operation of said motors, said means causing operation of said first motor to move said carriage forward to telescoping relationship of the grinding element and the work and then to cause said second motor to move said base transversely of said carriage to bring the grinding element andv the work into contacting relationship.

19. In a grinding machine of the class described, the combination of a bed, a grinding wheel rotatably supported thereby for movement relative thereto, a work support mounted on the bed, a pair of hydraulically actuable pistons for movement at right angles to one another, means for stopping the movement of the grinding wheel toward the work support, and means connecting one of the pistons with the grinding wheel for effecting the movement thereof and the other of the pistons with the stopping means for effecting relative thereto, a work support mounted on the bed, a pair of hydraulically actuable pistons for movement at right angles to one another, means for stopping the movement of the grinding wheel toward the work support, means connecting one of the pistons with the grinding wheel for effecting the movement thereof and the other of the pistons with the stopping means for effecting its actuation, and a common hydraulic mechanism for actuating the pistons including a pressure source and conduits from the pressure source to the pistons.

21. In a grinding machine, the combination of a bed, a grinding wheel support, a grinding wheel mounted thereon for rotation, fluid pressure means for moving said grinding wheel support rapidly transversely of said bed to position the grinding wheel for grinding, means for controlling the movement of the wheel support for producing a slow continuing grinding feed including a screw, fluid pressure operated means for rotating said screw, and means operated by said firstnamed fluid pressure means for initiating the operation of said last-named fluid pressure means when said feed wheel is positioned for grinding. 22. In a grinding machine, the combination of a bed, a grinding wheel support, a grinding wheel mounted thereon for rotation, fluid pressure means for moving said grinding wheel support rapidly transversely of said bed to position the grinding wheel for grinding, means for controlling the movement of the wheel support for roducing a slow continuing grinding feed of the wheel support in the same transverse direction, including a screw, fluid pressure operated means for rotating said screw, and automatic means for initiating the operation of said last-named fluid pressure means when said grinding wheel is positioned for grinding.

AMOS P. STEINER.

HAROLD E. BALSIGER.

EDGAR P. WINE.