US2883927A - Pneumatically operated identification marker - Google Patents

Description

April 28, 1959 E. EGBERT 2,883,927

PNEUMATICALLY OPERATED IDENTIFICATION MARKER Filed Dec. 5. 1955 Y 2 Sheets-Sheet 1 V T I I 44 a/ 45 39 25 45 27 20 44 24 3 I 30 26 28 34 33 g F 6! 6 l7 I INVENTOR. j W Lawrence E.Egberi /0- 2 7% fizz/r4 44 ATTORNEY Lawrence E. Egbert, Flint, Mich, assiguor to Herbert J. Booth, Flint, Mich.

Application December 5, 1955, Serial No. 550,885

2 Claims. (Cl. 101- The present invention relates to mechanisms that deliver hammerlike blows for stamping identification marks and symbols on metal parts. I

' An object of the invention is to provide a novel and improved marking apparatus which may be associated with metalworking machines for automatically or semiautomatically stamping marks on workpieces during multiple or individual construction of the workpieces or may be used as a bench machine for marking parts separate from the performance of construction operations thereon.

Another object of the invention is to provide an apparatus of the character set forth having therein a plunger that is actuated by a blast of compressed air of short duration and is spring-returned to its initial position immediately after application of said blast by a rapid dissipation of the spent blast.

, A further object of the invention is to provide, in an apparatus as outlined above, a novel pneumatic hammer unit in combination with a time-controlled. valve of a nature that is self-closed momentarily after being opened, and means for manually or automatically opening said valve.

A still further object of the invention is to provide, in an apparatus as set forth, a novel stand on which the pneumatic hammer unit and a control for actuation of the hammer of said unit are mounted and positioned relative to a workpiece rest on said stand, whereby a finger of a hand supporting the workpiece on the rest is used to actuate said control.

It is also an object of the invention to provide a device of the above-indicated character which is simple and substantial in construction, economical to manufacture, and thoroughly eflicient and practical in use.

' These, together with various auxiliary features and objects of the invention which will later become ap-. parent as the following description proceeds, are attained by the present invention, preferred embodiments of which have been illustrated by way of examples only in the accompanying drawings, wherein:

Figure 1 is a fragmentary plan view of a multiple work operation machine showing the improved identification marker attached thereto for performing a marking operation at one dwell station of the machine;

Figure 2 is a vertical enlarged section taken substan tially on line 2--2 of Figure 1;

Figure 3 is a cross section taken on line 3-3 of Figure 2;

Figure 4' is a side elevation with parts broken away and shown in section and showing the apparatus used as a bench machine; and v Figure 5 is a section and elevation view taken on line 5.5 of Figure 4. n

Referring now more specifically to the accompanying drawings wherein like numerals designate. similar parts throughout the various views, attention is directed first to Figures 1 and 2 wherein it will be. Seen that there is indicated, generally by the numeral 10., a per 2,883,927 Patented Apr. 28, 1959 tion of a metalworking machine of a nature for perform? ing multiple work operations to workpieces 11 as they are moved to different dwell stations of the machine. For the purpose of illustration, the machine 10 shown is of a type now extensively used in machining large pulleys, gear blanks, wheel hubs, et cetera, and is somewhat similar in construction to the machine disclosed in the patent to Edward P. Bullard, Jr., et al., No. 1,258,089, with the exception that all tool-carrying slides are raised and lowered simultaneously by a single vertical movable head in the performance of a series of different operations with different tools on a series of like workpieces. The machine has a stationary base 12, a turntable 13 with a plurality of chucks 14 thereon for the support of the workpieces 11, a vertically movable tool-carrying head 15, and a stationary upper frame 16. The turntable 13 indexes the workpieces to the different stations and directly beneath the different tools (not shown) 'on the head 15 for performing different oper, ations to the workpieces at different dwells of said workpieces. The tools carried by the head 15 and not shown may be of a number of different types; for example, tools that perform machining operations or dies for reforming workpieces.

The improved marker unit 20 for stamping identifie cation marks on the workpieces 11 is mounted at one of the dwelling stations of the machine and relative to a workpiece at the station by a pair of brackets '17 and 18 bolted to the base 12 of the machine, the marker being clamped to a horizontal arm 19 of the bracket 18. The bracket 18 is adjustable vertically on the bracket 17, and the marker 20 is adjustable horizontally on the arm 19 of the bracket 18 which permits proper positioning of the marker relative to workpieces.

The marker which was indicated generally by the numeral 20 has a housing consisting of an elongated cylindrical wall 21 and a pair of end Walls 22 and 23 with central openings 24 and 25, respectively, therethrough. Either or both of the end walls 22 and 23 may be constructed as a separate part and threaded upon the cylindrical Wall 21, as shown at 25, for at? tachment of the end wall 22 to the remainder of the housing. A piston 26, loosely fitted to the interior surface of the cylindrical wall 21 and having a rod 27 of reduced diameter fixed thereto and projecting forwardly through the opening 24 in the end wall 22, is mounted for reciprocatory movement in the housing. The opening 25 in the rear wall 23 of the housing is threaded and has screwed therein one end of a nipple 28 which has threaded on its opposite end a solenoid-operated lair valve 29 for controlling the flow of compressed air from an air supply hose into the housing to act upon the rear end of the piston 26 and force said piston forward.

About the rod 27, between the same and the inner surface of the cylindrical wall, and bearing at its'opposite ends on the end wall 22 and piston 26 is a compression spiral spring 30 for returning the movable plunger unit consisting of the piston and rod to its, initial position after actuation thereof forwardly by air from the valve 29. Another compression spiral spring 31 of shorter length is also located in the housing, but is between the piston 26 and the end wall 23. This last-mentioned spring acts as a buffer for absorbing the impact of the piston when returned by the spring 30.

In the free end of the rod 27, there is a socket iopening 32 into which is inserted and retained by a set screw 33 an end of a marker die 34. The marker die shown is of the simple, integral or one-piece type, but could just as well be the kind having an enlarged head that removably supports and retains a number of separate dies. Also in the rod 27 but along the side thereof is a longi tudinally extending key slot 35 into which projectea aeeape'r key 36 formed on the end of a screw 37 threaded into a radial opening 38 in the forward end wall 22 of the housing. The purpose of the key 36 is to retain the marker die 34- and plunger against turning movement so that all identification marks made by the marker die will be the same relative to their arrangement on the workpiece.

By having the piston 26 loosely fitted to the cylindrical wall, compressed air acting on the piston is permitted to escape around the piston and thus quickly decrease pressure behind the piston after the initial blast of :air has moved the piston forward a sufiicient distance to imbed the die marker into the workpiece. A plurailty of openings 39 are provided through the forward end wall 22 and outwardly of the central opening 24 therein for permitting air escaping past the piston to exhaust to the atmosphere. This construction, combined with the specific type of air valve 29 used, permits for quick return of the plunger of the marker by the spring 39 after marking a workpiece. The valve 29 is of the type that, upon energizing the solenoid, the air passageway therein is open for only a short and adjustable period of time independent of the length of time the solenoid remains energized. Thus,

air is delivered to the piston under high pressure in a blast of a short duration.

On the upper stationary frame 16 of the machine 10, there is mounted a microswitch 40 which has the movable circuit controlling arm 41 thereof in the path of movement of a trip member 42 carried by the vertically movable head 15 for causing an operation of the switch upon each upward movement of said head and prior to indexing the turntable to the next station. Leading from the switch 49 to the valve 29 and to the source of current are thin walled pipes 43 in which electric wires run for energizing the solenoid in the valve 29 upon each complete operation of the head 15 onto and off of the workpieces 11. Thus it can be seen that operation of the marker 20 is automatic during operation of the machine. While there is shown and described an electrically operated valve and means for automatically operating same, it is to be understood that an air-operated valve controlled by a separate valve and timed with operation of the machine can be employed so long as the valve at the entrance of air into the marker housing is capable of delivering a blast of air of a short duration upon each complete operation of the machine 10. It is further to be understood that the valve 29 may be of the type which is opened by energizing the solenoid thereof and which stays open only so long as the solenoid remains energized and that a spring-returned arm 41 of the switch 40 is in engagement with the trip member only so long as is required for said trip member to brush past said switch arm.

In the outer side of the cylindrical wall 21 of the marker housing, there is a pair of spaced annular grooves 44 that are semicircular in cross section and into which are received the bight portions of a pair of U bolts 45 which in turn have the end portions of their opposite legs extending through slotted openings 46 in the arm 19 of the bracket 18. Nuts 47 are located under the arm 19 and are threaded on the ends of the legs of the U-shaped bolts for clamping the marker housing in adjusted position to the bracket arm 19. This construction permits adjustment of the cylindrical housing both along and around its axis for proper positioning of the marker die 34 relative to the workpieces 11.

Figures 4 and illustrate the improved marking apparatus applied to and combined with a novel stand 50 workpieces 11 and the actuation of the microswitch 40 are manual.

The stand 50 has a hollow boxlike base 51 that is adapted to rest on or be clamped to the upper surface of the work bench or machine table. The upper horizontal wall 52 of the boxlike base provides an elevated platform upon which a V block 53 rests and is held against transverse movement by dowel pins 54 extending downwardly through openings in the wall 52. The microswitch 40 is mounted on the forward vertical wall 55 of the boxlike base 51 and, while being on the inside of said base, has its control, which is in the form-of a spring returned pushbutton 41 positioned exteriorly of said base. The positions of the pushbutton 41"- and the V block 53 are such that when a hand, as indicated in dotted lines in Figure 5, isholding a workpiece 11 on the V block 53, the index finger of the hand is at a location for convenient operation of the pushbutton 41 therewith.

A hollow inverted L-shaped post 56 extends upwardly from one side portion of the base 51 and has a solenoid-operated air valve 29 threadably connected, as at 57, to its upstanding vertical leg 58 and communicating with the hollow interior thereof. The other and horizontally arranged leg 59 of said inverted ,L- shaped post 56 extends over the base in spaced parallel relation thereto. Depending from the horizontal leg 59 and directly above a workpiece 11 in the V block 53 is a marker unit 20 identical in construction to the marker unit 20 previously described and shown in Figure 2. The die marker 34 on said unit is spaced a sufficient distance from the workpiece 11- to permit the momentum of the plunger of said unit to imbed the die into the workpiece. In this case, the marker unit is supported by threading the nipple 28 thereon and through which air enters said unit into an opening 60 in the lower wall of the horizontal leg 59. There is a lock nut 61 also threaded on the nipple 28 and engaging the wall of the leg for preventing turning movement of the marker unit. By having both legs 58 and 59 hollow and communicating at their connecting ends, a passageway 62 is provided for the flow of air from the valve 29 to the marker unit 20 Connecting the microswitch 40 to the solenoid-operated air valve 29 and to the source of current are Wires 63 for opening the valve upon manual actuation of the switch.

In view of the above description, taken in conjunction with the accompanying drawings, it is believed that a clear understanding of the construction, operation, and advantages of the improved invention will be quite apparent to those skilled in this art. A more detailed description is accordingly deemed unnecessary.

It is to be understood, however, that even though there are herein shown and described preferred em bodiments of the invention, various changes may be made without departing from the spirit and full intendment of the invention.

What is claimed is:

1. A pneumatically operated identification marker comprising a housing having a cylindrical wall, end walls on said housing and each having an opening therethrough that is centrally thereof, a piston in said housing and fitted relative to the inner surface of its cylindrical wall to permit an escape of air under pressure past said piston, a rod of reduced diameter fixed to one end of said piston and slidable through an opening in one end wall, said rod having a socket opening in its free end, a mark-er die rigidly supported in the socket in said rod, said end wall through which the rod extends having a plurality of other openings therethrough communicating the interior of said housing with the atmosphere, a compression spiral spring about said rod and between said piston and the end wall through which the rod extends, means rigidly supporting said housing in a position with said marker die spaced from and directed towards a workpiece to be marked by "said die, a

mechanism for delivering a blast of compressed air of a short duration to the interior of the housing through the central opening in the end wall opposite to that through which the rod slides, means for operating said blast-delivering mechanism, and a buffer spring in said housing between the piston and the end wall of the housing through which air is supplied to the housing.

2. An apparatus as defined in claim 1 wherein there is provided a longitudinally extending key slot in the side of the rod, and a key in said slot and removably supported on the end wall of the housing through which the rod extends.

6 References Cited in the file of this patent UNITED STATES PATENTS McDonough Dec. 17, 1918 Hauser Sept. 26, 1922 H'aupt 'Nov. 4, 1930 Vigne Sept. 26, 1933 Horling Sept. 28, 1937 Kovach Sept. 16, 1947 Triplett Mar. 20, 1951 Pannier Feb. 10, 1953 Zimmerman May 26, 1953

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