US2220471A

US2220471A - Grinding machine

Info

Publication number: US2220471A
Application number: US233838A
Authority: US
Inventors: Harold E Balsiger
Original assignee: Landis Tool Co
Current assignee: Landis Tool Co
Priority date: 1938-10-07
Filing date: 1938-10-07
Publication date: 1940-11-05
Anticipated expiration: 1957-11-05

Description

NOV. 5, 1940. BALSIGER 2,220,471

GRINDING MACHINE Filed Oct. 7, 1938 2 sneaks-sheet 1 a WWW Bnnentor Lw I HAR'OLD Earns/GER (Ittomeg NOV. 5, 1940. H, E BALSIGER 2,220,471

GRINDING momma Filed Oct. 7, 1938 2 Sheets-Sheet 2 ZSuventor (Ittomeg UNITED STATES PATENT OFFICE GRINDING MACHINE Harold E. Balsiger, Waynesboro, Pa., assignor to Landis Tool Company, Waynesboro, Pa.

Application October 7,

4 Claims.

My invention relates to grinding machines and particularly to the type known as chucking grinders.

It is an object of my invention to provide a 5 machine wherein the work and wheel will be separated automatically at the conclusion of the grinding operation.

It is a further object of my invention to provide means whereby a work ejector will be energized and the chuck opened after the work and wheel have been separated.

A further object is to cause the ejector to act before the chuck releases the work.. A further object is to cause the work ejector to return to normal position immediately upon performing its function.

Referring to the drawings:

Figure 1 is a partial plan view of the headstock.

Figure 2 is a wiring and piping diagram combined with an end view of a grinding machine cut away to show essential parts, and a plan view of the headstock partly in section.

The principal feature of my invention is the work ejecting mechanism and the method of operating same. Both the ejector and chuck are actuated by solenoids which are energized simultaneously. However, the chuck is actuated directly by a pressure operated piston and the solenoid actuates the valve which supplies the pressure mechanism to said piston. The ejector is actuated directly by its solenoid and the time required for the pressure medium to open the chuck permits the ejector to exert pressure on the work and when the chuck is opened the tension on the ejector is exerted to remove the work.

In the drawings numeral It indicates the headstock of a grinding machine, II a work piece mounted on a conventional chuck l2 of the expanding collet type, l3 a rod for operating said collet, l4 a piston at one end of said rod, l5 a. cylinder in which said piston is mounted, and IS a grinding wheel. The ejector mechanism consists of a forked member H for engaging the rear face of a work piece. Said member is attached to one end of a lever l8 pivoted at l9 to a housing 20. A spring 2| anchored in said housing and connected to said lever serves to hold forked member I! in inoperative position. The other end of said lever is pivotally attached to a lug 22 on the end plug 23 of a hollow cylindrical member 24. Within said cylinder is a spring 25 one end of which rests against the closed end of said cylinder. The other end engages one of a pair 1938, Serial No. 233,838

(or. 5l 105) of collars 23 and 21 threaded for adjustment on a rod 28. Said rod extends thru the closed end of said cylinder where it is connected to the armature 29 of a solenoid 30.

Fluid under pressure for operating chuck I2 is supplied by a pump 3| thru a reversing valve 32. Said valve is shifted in one direction by a solenoid 33 and in the opposite direction by a spring 34.

Grinding wheel I6 is rotatably supported on wheel base 40 which is slidably mounted on bed 4| for movement toward and from operative position. Said movement is effected by a piston 42 in cylinder 43 acting thru piston rod 44 which is connected to said wheel base. Fluid under pressure from said pump 3| is directed to one end or the other of cylinder 43 thru reversing valve 45. An elongated stem 46 on said valve is connected to a pivoted hand lever 41. Said lever is held in the position shown by latch 48 against the action of a spring (not shown). Said latch may be released either by push button 49 or solenoid 50.

Operation After the operator has placed an unground work piece on chuck l2, he pulls forward on lever 41 to shift valve and direct fluid under pressure to the rear of cylinder 43 to move wheel base 40 and grinding wheel Hi to operative position. .This movement of lever 41 releases normally closed switch 55 to close a circuit from line 2 thru line 56 and said switch to a timing mechanism 51, thru line 58 back to line I. The grinding operation continues until the end of the period for which the timing mechanism is set at which time said mechanism energizes solenoid to release lever 41. A spring (not shown) returns said lever to its initial position where it opens switch to stop timing mechanism 51. When said timing mechanism is stopped it resets itself for the next operation. Returning said lever 41 to its initial position also results in shifting valve 45 to a position to direct fluid under pressure to the rod end of cylinder 43 to withdraw the wheel [6 from grinding position. In the rear position of wheel base 40, normally closed limit switch 60 is released to close a circuit from line 2 thru line BI and line 62 to energize solenoid 33, and thru the normally closed contacts 63 of relay 54 to energize solenoid 30. Solenoid 30 immediately acts thru rod 28 to place spring 25 under tension since ejector fork ll cannot move until the work II is released from chuck l2. Solenoid 33 is energized at the same time as solenoid 30 and they function simultaneously. However, solenoid 33 shifts valve 32 to direct fluid under pressure to the head end of cylinder l5. Thus while valve 32 is being shifted. elector fork I1 is being urged against the work I I. Then when piston I4 is shifted to open chuck II, the tension in spring 25 is utilized to move lever I8 rapidly in a clockwise direction and fork ll being attached to said lever, removes the work piece II from the chuck l2. When lever I8 is in normal position as shown in the drawings an extension IB' on said lever holds a normally closed limit switch 10 in open position. When said ejector functions to remove a work piece from the chuck, switch 10 closes a circuit from line 2 thru line H to energize relay 64 and open the circuit thru contacts 63 and deenergize solenoid 30. At the same time a holding circuit for said relay is closed thru the normally open contact 12, line 82 and wheel base operated limit switch 60. When solenoid 30 is deenergized, spring 21 re-sets the ejector mechanism and opens the circuit thru switch 10. When wheel base 40 again moves forward, the operator having first placed a new piece of work on the chuck, it depresses limit switch 60 and opens the circuit to relay 64 and contacts 63 and I2 resume their normal positions. At the same time solenoid 33 is deenergized and spring 34 shifts valve 32 to direct fluid to the rod end of cylinder l causing piston M to pull rod l3 to expand chuck I2 and grip work piece II in preparation for the next grinding operation.

I claim:

1. A grinding machine comprising a bed, a wheel support slidably mounted thereon, a work support including a chuck and means for operating same, an ejecting mechanism for removing work from said chuck, mechanism including a solenoid for causing said ejector to exert pressure on a work piece at a predetermined time and before said work piece is released by said chuck, and means operable in response to movement of said ejector upon release of said work piece by said chuck for deenergizing said solenoid.

2. In a grinding machine a work support including a headstock, a chuck on said headstock, pressure means for operating said chuck to hold or release a work piece, a valve for controlling said chuck, a solenoid for operating said valve, an ejector for removing work from said chuck, a solenoid for operating said ejector, a switch operable to energize both said solenoids, and means whereby said ejector is caused to exert pressure against said work piece prior to the release thereof from said chuck.

3. A grinding machine comprising a bed, a grinding wheel support slidably mounted thereon, a work support including a'headstock mechanism, a chuck rotatably mounted thereon, an ejector for removing work from said chuck, means for moving said wheel support and said work support relatively and transversely toward and from grinding position, mechanisms responsive to said movement from grinding position for'initiating operation of said ejector and said chuck independently one of the other, and means for delaying the. operation of said chuck until after said ejector operating means has been actuated.

4. In a grinding machine, a work support including a headstock mechanism, a chuck rotatably mounted thereon, an ejector for removing work from said chuck, means for holding said ejector in inoperative position, mechanisms for actuating said chuck and said ejector, means for initiating operation of said ejector andv chuck independently one of the other, means for causing said ejector to exert pressure against said work piece prior to the release thereof from said chuck, and means set in operation by actuation of said ejector for rendering inoperative said ejector actuating mechanism and permitting return of said ejector to inoperative position.

HAROLD E. BALSIGER.