US2535490A - Automatic electric index fixture - Google Patents

Description

Dec. 26, 1950 M. H. EMRICK v 2,535,490

AUTOMATIC ELECTRIC INDEX FIXTURE Filed May 20, 1949 Til.

2 Sheets-Shee 1 3. 2 T lulu m @7' lo O47 I 5! l f mw@ wumlm ATTORNEY Dec. 26, 1950 M. H. EMRICK AUTOMATIC ELECTRIC `INDEX FIXTURE 2 Sheets-Sheet 2 Filed May 20, 1949 INVENTOR. MELVIN H. EMRICK ATTORNEY Patented Dec. 26, 1950 UNITED STATES PATENT OFFICE AUTOMATIC ELECTRIC .INDEX FIXTURE Melvin H. Emrick, Jamaica, N. Y.

Application May'20, 1949, Serial No. 94,340

l8 Claims. 1

This invention relates to index xtures for use in conjunction with various types and kinds of machines for intermittently positioning workpieces in a machine in automatically performing one or more operations on the workpieces. More particularly, the invention deals with a fixture of the character described, wherein positive means is employed for moving the workpiece table keypin into operative and inoperative positions in the successive indexing operations of the table. Still more particularly, the invention deals with a ixture of the character described having means for automatically braking the motor shaft in holding the xture at rest during the period of performing operations upon workpieces actuated by the fixture.

The novel features of the invention will be best understood from the following description, when taken together with the accompanying drawings, in which certain embodiments of the invention are disclosed and, in which, the separate parts are designated by suitable reference characters in each of the views and, in which:

Fig. 1 is a sectional plan view of a fixture made according to my invention, omitting the electric wiring employed.

Fig. 2 is a section substantially on the line 2-2 of Fig. 1 showing part of the construction in elevation and with parts broken away.

Fig. 3 is a section substantially on the line v3--3 of Fig. 1 on an enlarged scale and with part of the structure in elevation.

Fig. 4 is a diagrammatic view illustrating the wiring diagram; vand Fig. 5 is a partial section on the line 5-5 of Fig. 1.

My present invention is an improvement of Vthe invention shown and described in my prior application, Serial Number 75,770; filed February 11, 1949 and the present invention deals primarily with the method of actuating the keypin and the means for braking the motor shaft and change in the wiring consistent with the new structure employed.

In 'illustrating my invention, I have shown in Figs. 1 and 2 of the drawing a unitary casing IIJ, substantially similar to the casing of my prior application and this casing houses the operative parts of the fixture. The casing Ill is open at the bottom, as will appear from a consideration 'ci Fig. 2 and the casing has side walls II of the general cross-sectional form, seen in Fig. 1 of the drawing, the walls being offset, as seen at I2, for support of a capacitor I3.

Another offset wall I4 is opposed to the wall.

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2 I2 and to this latter wall is secured a bracket I5 for support of guide rods vI6 to position ,the xture in a machine. The left side of the casing I0, as seen in Fig. 1, has a box-shaped compartment I1 in which is disposed an electric ref lay mechanism diagrammatically shown in Fig. 4

at I8 and blankly outlined in Fig. 1.

The compartment .I1 has openings I9 and 20, through which circuit wires extend to the capacitor I3, a combination micro-switch and solenoid '2l and an electric motor 22. The micro-switch 2| `is supportedl in a bracket portion 23 in the casing at the right thereof, as seen in Fig. l. The lower portion of the casing has flange portions 24 at the corners thereof, for additional mounting in connection with Athe table or baseplate of a machine. The top of the casing has a rather heavy supporting plate 25, note Fig. l2 in connection with which the motor 22 is hung., the plate having a bearing portion 26 for a shaft 21 of a Geneva-type indexing element 28. The top 25 of the casing also has a depending bearing portion 29 for the shaft 30 of a drive unit 3l.

A motor shaft32 is coupled with va worm gear shaft 33 to a flexible coupling 34. The shaft 33 is mounted in another depending fork-shaped bearing 35 having a partial housing 36, note Fig. 1, for retention of lubrication therearound, particularly to lubricate the worm 31 on the shaft within said housing. The housing 36 is removed in the showing in Fig. v2 in order to clearly il lustrate the worm 31. Means for lubricating the housing 36 externally of the casing isseen at 38. It will be noted that the shaft 33 extends externally -of the casing terminating in a square or angular end 39, whereby a crank or other tool can be yutilized to turn the shaft vmanually whenever desired. On the shaft 30 is arranged a worm gear il which meshes with the worm 31.

The worm gear '40 comprises part of the drive unit 3 I. Another part of the unit incl-udes a cam groove 4I having a raised portion 42, which extends between the positions 43, 44, as Anoted in Fig. 1 of theA drawing. Leading up to the ends 43, 44 are bevelled surfaces 45 and 46 which join the lower surface 42' of the cam groove with the upper surface 42 thereof. The cam groove 4l controls operation of a plunger keypin 41;, note Fig. 5. The pin 41 is mounted in a bushing 48, secured in the top wall 25, the pin carrying, at its lower end, a stud 41 supporting a roller 49 which operates in the Vcam groove 4I to control movement of the pin 41 into and out of a series of circumferentially spaced apertures or sockets i in an index plate 5I of the machine.

The plate 5! is mounted for free rotation around a reduced end 21' of the shaft 21 in moving a workpiece or a series of workpieces on the plate 5I with respect to a forming tool of a machine. In Fig. 4 of the drawing, an upper portion of a tool is diagrammatically seen at 52.

In Fig. 5 of the drawing, the pin 4'! is shown in a recess. or socket 50 to key the plate 5| against rotation. The roller 49 of the pin is disposed in the cam groove 42.

Carried by and protruding from the lower surface of the drive unit 3|, or the worm gear 40 thereof. is a stud 53, upon which is mounted a roller 54. note Fig. 3. The roller 54 is adapted to enter successive notches 28 of the indexing element 28 in intermittent rotary shifting of the plate 5I for indexing the work thereon. In Fig. l of the drawing, the roller 54 is shown in a position preparatory to entering the notch or recess 28 of the element 2-8, the plunger keypin 41 being still in the raised position. As the gear 40 is rotated, the drive pin of the gear, represented by the stud 53 and roller 54, will start to enter the recess 28 as and when .the plunger keypin 4'.' has reached its lowermost position and disengages the plate 5I. Continuation of rotation of the gear 4!! will cause the element 28 to be actuated one sten. at which time, the drive pin will move out of the recess ZIB" and the keypin 4'! will again be moved into raised position by movement of the roller 49 onto the raised surface 42 of the cam groove.

lSupported in conjunction with the microswitch and solenoid unit 2! on a bracket 55 is a pivoted arm 5S carrying. at its free end a roller 51. Suitable means is provided to maintain the arm 56 and roller 51, such for example as the spring not shown. in operative position as, in other words, with the roller 51 in the path of movement of the drive pin 53 or the roller 54 thereon.

It will thus be seen that, as the drive pin passes the roller 51, tbe arm 56 is swung to the right to actuate a micro-switch element 2|' for purposes later described. 'This action takes place when the roller 49 is able to ride onto the inclined surface 45. At this instance, actuation of the micro-switch 2| will break the circuit to the motor 22 and, at the same time, actuate the solenoid 58 diagrammatically seen in Fig. 4 of the drawing, which operation will move a brake arm 59 to move the brake shoe 6'! on the arm into engagement with the shaft 33 so as to brake rotary movement of the motor shaft to bring the roller 49 to a stop position on the surface 42. substantially as seen in Fig. 1. In some instances. the use of the brake shoe 6I] and the means for actuating the same will not be necessary and suiiicient frictional engagement will be provided to stop the movement of the roller 49 on the raised surface 42 at a point where the drive pin 53 is still out of engagement with a notch of the Geneva 28.

One side of the casing has a suitable tting 6I through which circuit wires, diagrammatically seen at 62, are admitted into the box I1. These wires form a series of electric currents and are diagrammatically seen at'63 and 64 in Fig. 4 of the drawing. In this gure, the various mechanisms of the index xture are diagrammatically shown without regard for relative positions thereof one with respect to the other. The tool 52 has a trip arm 52', diagrammatically shown for actuating a micro-switch 65.

In the diagrammatic sketch, 66 represents a foot or hand switch controlling the machine operation and, at 61, is a suitable switch solenoid mechanism used to control spindle or tool actuation. Tracing the circuit, it will appear that the wire 63 extends to a solenoid actuated switch arm 58, actuated by a solenoid '69 in the relay mechanism I8. The wire 63 also extends to the control switch 65 and to the unit 51. From the latter, a wire 1I) extends to a contact 1! in the micro-switch mechanism ZI. Normally the switch arm 12 of the micro-switch mechanism is in engagement with a contact 13, which leads to a Contact arm 1li of the relay mechanism I 8. Also in this circuit is a wire 15 which goes to the solenoid 69 and then to a circuit wire 15 which extends to the micro-switch $5 and also to a circuit wire 'i1 having a contact 18 adapted to be engaged by the contact plate '$3 and also extending to the capacitor I3. From the capacitor I3 is a wire 19 which extends to the electric motor, another wire 11 extending from the wire 1'! to the motor and from the motor is a wire '8U which extends to a contact SI of the relay. The solenoid 58 is placed in the circuit by wires 82, =83; the wire `82 contacting the wire 8D and the wire 83 contacting the wire 11', as noted.

It will be understood that, in actuation of the solenoid B9, the circuits are completed through the plate 58 and contact 18 and the plate 14 and contact 8l. The indexer is automatically actuated in the following manner, assuming that the parts are in the position, as seen in Fig. 1, and operation is being performed upon the workpiece and the tool 52 or the spindle supporting the same is being moved into raised position out-of-engagement with the workpiece.

When the arm 52 strikes the micro-switch E5 to actuate the switch, this operation will close the circuit to the relay, thus putting the electric motor 22 into operation through the capacitor I3, which automatically puts the drive unit 3! into operation. In this operation, the keypin 4'! will be first released from engagement with the plate 5I; then the plate will be rotated one step, controlled by the feed motion of the Geneva element 28 employed and, as this operation is completed and the pin 41 again is moved into another key socket of the plate 5I, the arm 56 is tripped, as above stated, to actuate the switch element 2I' of the micro-switch 2 I, causing the contact 12 to move into engagement with the contact 1I, thus closing the circuit to the control switch 6'! to again put the machine driving the tool 52 into operation. In the movement of the contact 12 into engagement with the contact 1I, circuit is broken through the contact 13, thus automatically breaking the motor circuit, causing the motor to come at rest, whereupon the contact 12 is again moved into the closed circuit position with the contact 13, preparatory to the next descending operation of the tool 52. In other words, when the tool again reaches its raised position, the micro-switch 65 will again be actuated to repeat the above-described operation. Control through the switch 66 may be automatic or, this switch can be manually operated in each intermittent actuation of the element 22, depending entirely upon the type of work being performed on the machine or the degree of automatic operation which may be required.

In the above-described operation, if the brak mechanism is employed or, in other words, the

tions thereon. In other words, a machine `of this kind can be utilized where operations -on the workpiece `are performed by hand, in which event, suitable controls will be provided for intermittent actuation of the motor and feed of the work supporting table or plate 5|.

Having .fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An apparatus of the class described comprising a casing, a workpiece supporting plate rotatably mounted on the casing, a Geneva engaging said plate for imparting intermittent rotation thereto, a drive unit for actuating said Geneva, said unit having worm gear, means cornprising a motor driven worm engaging said worm gear for intermittently operating said Geneva, said unit including a cam portion, a lock pin slidably mounted in the casing and directly actuacted by the cam portion of said unit to control movement of the lock pin into operative and inoperative position with respect to said plate in intermittently retaining the plate in predetermined position, and means comprising a switch in the casing adjacent said unit and-in electric circuit with said motor and actuated by said unit to control intermittent drive of the unit.

2. An apparatus of the class described comprising a casing, a workpiece supporting plate rotatably mounted on the casing, a Geneva engaging said plate for imparting intermittent rotation thereto, a drive unit :for actuating said Geneva, said unit having worm gear, means comprising a motor driven worm engaging said worm gear for intermittently operating said Geneva,

said unit including a cam portion, a lock pin slidably mounted in the casing and directly actuated by the cam portion of said unit to control movement of the lock pin into operative and inoperative pcsition with respect to said piate in intermittently retaining the plate in predeterminted position, means comprising a switch in the casing adjacent said unit and in electric circuit with said motor and actuated by said unit to control intermittent drive of the unit, and means externally of the casing controlling the electric motor circuit.

3. An apparatus of the class described comprising a casing, a work-piece supporting plate rotatably mounted on the casing, a Geneva engaging said plate for imparting intermittent rotation thereto, a drive unit for actuating said Geneva, said unit having worm gear, means comprising a motor driven worm engaging said worm gear for intermittently operating said Geneva, said unit including a cam portion, a lock pin slidably mounted in the casing and directlyactuated by the cam portion of said unit to control movement of the lock pin into operative and inoperative position with respect to said plate in intermittently retaining the plate in predetermined position` means comprising a switch inthe casing adjacent said unit and in eleotriccircuit with said motor and actuated by said 4unit to control intermittent drive of the unit, means externally of the casing controlling the electric motor circuit; and an automatically a;crustedv brake' ele*- inent in the casing and operatively engaging the yshaft of the worm for checking rotation of-'the motor in stopping action 'of said unit. 4. An index iixtureof the character described comprisingl a casing, a table mounted for inter'- mittent rotary movement on said casing, indexing mechanism within the casing 'for' intermittent-ly actuating said table and to key the table in a plurality of indexing positions, said indexing mechanism including an electric motor, means comprising a switch in the casing adjacent said indexing mechanism and automatically actuated by said indexing mechanism to break` the circuit to said motor in intermittently stopping actuation of said mechanism, means comprising a switch externally of the casing for completing the circuit to said motor to actuate said indexing mechanism, the table 1xeying means of said mechanism comprising a pin, and said mechanism including a cam positively moving said pin into operative and inoperative positions.

5. An index iixture of the character described comprising a casing, a table mounted for intermittent rotary movement on said casing, indexing mechanism Within the casing for intermittently actuating said table and to key the table in a plurality of indexing positions, said indexing mechanism including an electric motor, means comprising a switch in the casing adjacent said indexing mechanism and automatically actuated by said indexing mechanism to break the circuit to said motor in intermittently stopping actuation of said mechanism, means comprising a switch externally of the casing for completing the circuit to said motor to actuate said indexing mechanism, the table keying means of said mechanism comprising a pin. said mechanism including a cam positively moving said pin into operative and inoperative positions, and means within the casing of the iixture operatively engaging a motor driven shaft to check rotation of said shaft in movement of the pin into operative position.

6. An index iixture of the character described comprising a casing, a table mounted for intermittent rotary movement on said casing, indexing mechanism within the casing for intermittently actuating said table and to key the table in a plurality of indexing positions, said indexing mechanism including an electric motor, means comprising a switch in the casing adiacent said indexing mechanism and automatically actuated by said indexing mechanism to break the circuit to said motor in intermittently stopping actuation of said mechanism, means comprising a switch externally of the casing for completing the circuit to Said motor to actuate said indexing mechanism, the table keying means of said mechanism comprising a pin` said mechanism including a cam positively moving said pin into operative and inoperative positions, means within the casing of the iixture operatively engaging a motor driven shaft to check rotation of said shaft in movement of the pin into operative position, and means automatically controlling actuation or said last named means.

7. An index xture of the class described comprising a casing, a workpiece supporting table rotatably mounted on the casing, a drive unit in the casing, said unit comprising a drive pin and a cam, means comprising an electric motor for intermittently actuating said unit, a member intermittently engaged by the drive pin for imparting intermittent rotary movement to said table, a key Apin directly actuated by said cam for movement into and out of key position with the table, a switch mechanism in an electric circuit to said motor, said mechanism including a switch element adjacent and automatically actuated by said unit controlling intermittent operation of the unit and said table.

8. An index xture of the class described comprising a casing, a workpiece supporting table rotatably mounted on the casing, a drive unit in the casing, said unit comprising a drive pin and a cam, means comprising an electric motor for intermittently actuating said unit, a member intermittently engaged by the drive pin for imparting intermittent rotary movement to said table, a, key pin directly actuated by said cam for movement into and out of key position with the table, a switch mechanism in an electric circuit to said motor, said mechanism including a switch element adjacent and automatically actuated by said unit controlling intermittent operation of the unit and said table, and electrically actuated brake means in said circuit for automatically stopping rotation of the unit in movement of said key pin into inoperative position.

MELVIN H. EMRICK.

No references cited.

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