US3557649A

US3557649A - Centering and piercing process and apparatus

Info

Publication number: US3557649A
Authority: US
Inventors: Myron C Kirchner
Original assignee: NORTHERN METAL PRODUCTS Inc
Current assignee: NORTHERN METAL PRODUCTS Inc
Priority date: 1968-12-16
Filing date: 1968-12-16
Publication date: 1971-01-26
Anticipated expiration: 1988-01-26

Abstract

A process and apparatus for forming a plurality of precisely located openings in the flange of a metal frame for a shadow mask assembly. The apparatus includes expansible means for precisely locating the frame on a support prior to the formation of the openings by a plurality of piercing units. The apparatus also includes means engageable with a horizontally disposed midportion of the frame for sensing flatness thereof.

Description

United States Patent Inventor Myron C. Kirchner Itasca, Ill.

Dec. 16, 1968 Jan. 26, 1971 Northern Metal Products, Inc.

a corporation of Delaware Appl. No.. Filed Patented Assignee CENTERING AND PIERCING PROCESS AND APPARATUS 15 Claims, 9 Drawing Figs.

US. Cl 83/54, 83/180, 83/193, 269/481 Int. (1 B261 1/02 Field of Search 83/54, 178,

[56] References Cited UNITED STATES PATENTS 1,581,810 4/1926 Patrick 83/181 1,768,357 6/1930 83/181 1,878,520 9/1932 83/182 2,413,103 12/1946 269/48.1X 3,100,413 8/1963 Varga 83/180 Primary Examiner-Frank T. Yost Arrorney-Dressler, Goldsmith, Clement & Gordon ABSTRACT: A process and apparatus for forming a plurality of precisely located openings in the flange of a metal frame for a shadow mask assembly. The apparatus includes expansible means for precisely locating the frame on a support prior to the formation of the openings by a plurality of piercing units.

The apparatus also includes means engageable with a horizontally disposed midportion of the frame for sensing flatness thereof.

PATENTEU JAH26 1971 SHEET 3 OF 5 IAN EH70 Z 4 7 TOP/YE y:

. APPAR T BACKGROUND oF T na INVENTION Shadow mask assemblies for color television tubes are conventionally formed by securing the peripheral flange of a foraminous concave-convex sheet to an open rectangular frame. The frame is a one piece metal stamping that conven tionally includes three brackets on the sides thereof for mounting the assembly within a color television tube. In the shadow mask assembly with which the present invention is concerned, the mounting brackets are the'forrn of leaf springs havingend portions that are bent. inwardly toward the frame of the assemblyl A plurality of openings are provided in th s e b y rame th ch p n ng b i align d n of the bent spring end poi'tions so to allow thespi'ing end portion to flex inwardly of the assembly frame, when the assembly ismounted'within a color television tube. In order that the shadow maskassembl y will be correctly positioned within the color television tube, and to facilitate, subsequent manufacturing steps, it is essential that the above-mentioned openings be precisely located inthe frame of the assembly,

SUMMARY 01 T e INVENTION The present invention provides a novel centering means for accurately positioning'the frame of-a shadow mask assembly on a piercing machine, 'so that openings be formed in the frame at precise locations thereonYIfhe centering means includes. a plurality of expansible means, with a first expansible means being movable along one centerline of the frame, and withsecond and third, expansible means being spaced, equally from and movable paralleljwith the second center line of the frame. The frame of the shadow mask assembly includes 'a de- 3 horizontally disposed portion ofthe frame for sensing flatness thereof prior to the actuation of the centering means and the piercing means. v

Ban-3F DESCRIPTION. OF THE DRAWINGS FIG. 1 is a perspective view of a frame for a shadow mask assembly;

FIG. 2 is a top. plan view of the apparatus of the present invention; A i

FIG. 3. is an enlarged? fragmentary plan view of a portion of the apparatus illustratedjn. FIG. 2;

FIG. 4. is asectional view taken generally along line 4-4. of 7 FIG. 3;

FIG. 5 is a sectionalview taken generally along line 5-5 of no.3; nd1

EIGS. 6, and;6A-6 .C are schematic electrical diagrams of the control: system of the present invention.

oEsc rPno OF THE P EEERRBD M IMENT While this invention is susceptible of embodiment in many different forms, there is shown, in the drawings andwillherein be described in detailone specific embodiment, with the understanding that the present disclosure is to be considered as an exemplification. of the. principles ofthe'invention and is not intended to. limit the invention to the embodiment illustrated.

The scope oftheinvention. willjbe pointed out in the appended claims.

The locatingand piercingapparatus of the present invention is .illust 'ated'generally at 10in the drawings, and the shadow mask assembly frame that is operated upon by the ap- 75 paratus of the present invention is illustrated generally at 11 in FIG. 1. The frame 11 is an open generally rectangular sheet metal part for use in a generally rectangular color television tube. The frame 11 includes a generally horizontally extending midportion 12, with a peripherally continuous skirt 13 extending downwardly from the outer edge thereof. A flange 14 is offset outwardly from skirt l3 and extends downwardly therefrom. A further peripherally continuous flange 15 extends upwardly and inwardly from the inner edge of frame 10 portion 12. A plurality of mounting brackets 16 are secured to frame 11 for mounting the shadow mask assembly within a color television tube, and mounting brackets 16 are in the form of a leaf spring 17 having an inwardly bent end portion 18. Leaf springs 17 include a generally triangularly shaped opening 19 adjacent the bent end thereof, for cooperative engagement with a mounting stud on a color television tube, as is well known. The end of leaf springs 17 opposite from bent portion 18 are secured to a generally L-shaped support bracket 20. that are secured to the horizontal portion 12 of frame 11. The mounting brackets 16 are secured to the frame 11 with the leaf springs 17 extending downwardly at a slight angle, and with the bent end portions 18 of the leaf springs being positioned in alignment with square opening 21 in the skirt 13 of the frame 11. The openings 21 are formed by the piercing apparatus to be hereafter described, and before the openings 21 can be formed, the frame 11 must be accurately positioned relative to the piercing apparatus.

The locating and piercing apparatus 10 is illustrated in its entirety in FIG. 2, and the apparatus includes a base plate 22, with a plurality of expansible means 23-25 being mounted for movement relative to base plate 22. A plurality of piercing units 2628 are also mounted for movement relative to base plate 22.

The expansible means 23-25 are all structurally similar, and the structure thereof can be best understood from FIG. 5, where the expansible means is. shown in detail. Expansible means 25 includes a horizontally disposed lead screw 29 positioned above base plate 22 in parallel relationship therewith.

9 Lead screw 29 has oppositely threaded portions at opposite ends thereof, with one threaded portion being shown at 31 in FIG. 5. Generally identical support structure is provided at both ends of lead screw 29, and only the support structure at the right-hand end of lead screw 29, as viewedin FIG. 5, is illustr'ated and described in detail. Elements at the left-hand end of lead screw 29 which correspond to those at the righthand end of the lead screw, and which are illustrated, have been given the subscript a. A socket 32 is provided in the right-hand end of lead screw 29, and the end portion 33 of coupling member 34 is nonrotatably received in socket 32. A coupling member 34 at the right-hand end of lead screw 29 extends through an opening 35 in a shaft support block 36, and a pair of spaced bushings 37 are provided in the opening 35 to rotatably support the coupling member 34. The left-hand end of lead screw 29is also rotatably mounted in a support block 36a. Thrust bearings 38 are mounted on coupling member 34 adjacent block 36, and a bearing, retainer, in the form of a locknut 39, is securedupon coupling member 34 outwardly of 0 block 36,.

-Means is provided for connecting. the lead screw 29 to a source of rotary motion, and to this end, a coupling sleeve 41 is secured to the end of coupling member 34 that extends outwardly from locknut 39, and a worm shaft 42 is fixed within sleeve 41. Teeth 43-on shaft 42 mesh with a worm gear 44 on the output shaft of a motor 45 for rotating the lead screw 29. The motor 45 is mounted upon a support 46 that is secured to base 22.

Follower means 47 cooperate with the threaded portions of the lead screw 29, and the follower means 47 are in the form of a ball bearing nut 48 having an enlarged flange 49. The flange 49 of each ball bearing nut is secured to a slide member 51 that is mounted for movement with an upwardly opening slot 52in a mounting block 53 which is secured to the base 22. 1 A flange 54 extends laterally outwardly from the upper end of each slide 51, and an abutment means 55 is mounted upon flange 54. Each abutment means 55 is in the form of a metal roller 56 that is mounted upon a shaft 57 which extends downwardly through an opening in flange 54, with a nut 58 being threaded upon the externally threaded lower end of shaft 57. As is evident from FIG. 3,

rollers

56 and 56a are positioned in alignment with a centerline through the short sides of rectangular skin 13. Thus, when frame 11 is positioned upon support structure to be hereafter described, and when motor 45 is energized to rotate lead screw 29 in a first direction,

slide members

51 and 51a are moved outwardly until

rollers

56 and 56a engage the flange 14 of skirt 13. When both rollers engage the skirt, motor 45 is deenergized by electrical circuitry to be hereafter described, and the frame 11 is centered relative to the centerline along which

rollers

56 and 56a move.

Because of the structural similarities between expansible means 23 and 24 and expansible means 25, reference numerals in the 100 and 200 series are used to designate the elements of expansible means 23 and 24, respectively, which correspond to similar elements of expansible means 25.

As is evident from FIG. 2, lead screws 129 and 229 are parallel to one another and perpendicular to lead screw 29. Lead screws 129 and 229 are spaced equally outwardly from the centerline of the rectangular frame 11 that extends through the long sides thereof. As can be best seen in FIGS. 4 and 5, the grooves in the mounting

blocks

153 and 253 for supporting

slides

151 and 251, respectively, are positioned above groove 52 so as to support

lead screws

129 and 229 for rotation in a plane above lead screw 29. As will be hereinafter explained in connection with the electrical control means illustrated in FIG. 6 and FIGS. 6A6C, after

motors

145 and 245 are energized, the rollers associated with

slides

151, 151a, 251 and 251a move outwardly into engagement with the flanged portion 14 of skirt 13, and after both rollers of each set move into engagement with the skirt, the respective motors are deenergized. When only one roller of a set of rollers engages the skirt of the frame, the motor remains energized until both rollers of the set engage the skirt, and in this manner, the frame is precisely centered relative to the centerline through the long sides of the rectangular frame.

After the frame 11 is centered upon the base 22, piercing units 26-28 are actuated to form the holes 21 in the skirt 13. The piercing units are identical, and the structure thereof will be best understood from a consideration of FIG. 4, where piercing unit 26 is illustrated. The elements of piercing

units

27 and 28 which correspond to those of piercing unit 26 have been given similar reference numerals in the 100 and 200 series, respectively. As is illustrated in FIG. 4, where piercing unit 26 is illustrated. The elements of piercing

units

27 and 28 which correspond to those of piercing unit 26 have been given similar reference numerals in the 100 and 200 series, respectively. As is illustrated in FIG. 4, piercing unit 26 includes a punch 60 that is mounted for reciprocal movement into and out of hole piercing engagement with skirt 13 of frame 11, the punch 60 being illustrated in its innermost hole piercing position in FIG. 4. Punch 60 is carried within a socket 61 of a ram 62 of a hydraulic cylinder assembly 63. Hydraulic cylinder assembly 63 is a conventional one way device, with the ram 62 being urged inwardly by a spring, not shown, and with the ram being movable outwardly by fluid under pressure.

The hydraulic cylinder assembly 63 includes a rectangular housing member 64 that is welded, or otherwise suitably secured, to a mounting plate 65, which in turn is secured to the upper surface of an elongate rectangular carrier tube 66. A pair of mounting lugs 67 and 68 extend downwardly from tube 66, and a mounting shaft 71 is slidably received in aligned openings 69 and 70 in lugs 67 and 68, respectively. The outer ends of shaft 71 are slidably supported in bearing blocks 72 and 73 on base 22, and bushings 74 and 75 are provided in aligned openings 76 and 77 in bearing blocks 72 and 73, respectively.

A stop plate 78 is positioned outwardly of bearing block 72, and a screw 79 extends through an opening 80 in stop plate 78, with the end of screw being threaded into an internally threaded opening 81 in the end of shaft 71. A helical spring 82 surrounds screw 79, to urge the entire mounting structure for the cylinder assembly 63 to the left as viewed in FIG. 4. Thus, when fluid under pressure is admitted into the hydraulic cylinder assembly 63 to force the ram 62 outwardly thereof to move the punch 60 into hole piercing engagement with skirt 13, spring 82 absorbs the reaction force on the cylinder mounting structure and cushions the impact of the punch 60. A guide shoe 83 extends downwardly from tube 66 at the rearward end thereof, and slides within an upwardly opening slot 84 in mounting block 73 to guide the cylinder mounting structure.

A die yoke 85 is fixed to the upper surface of tube 66 inwardly of plate 65, and yoke 85 has a generally rectangularly shaped recess 86 in the upper surface thereof. Yoke 85 also includes a recess 87 in the outer face thereof in alignment with recess 86, and a generally L-shaped die block 88 is secured to yoke 85, with the die block including a first section 89 seated within recess 86 and a second section 90 seated within recess 87.

Rough locating means is provided on base 22 for initially retaining the frame 11 when it is positioned on the support structure. The rough locating means includes four upright guide posts 99 having rounded outwardly facing guide surfaces 990 that are adapted to engage the rounded corners of the skirt 13 of the frame when the frame is positioned on the support structure. Flatness-sensing means are associated with the rough locating means, and to this end, switch actuating plungers project upwardly from the upper surface of the guide posts 99 so as to engage the comers of the flat portion 12 of the frame 11. If the corners of the flat portion 12 of the frame are disposed in a common plane, the plungers 100 will be depressed an amount sufficient to actuate switching means to be hereafter described in connection with FIG. 6.

When the frame 11 is positioned on base 22, the horizontally disposed frame portion 12 is seated upon the upper surface of die block sections 86, 186 and 286. The downwardly extending skirt 13 is positioned outwardly of die block sections 87, I87 and 287. Openings 87a, 187a and 2870 are provided in the downwardly extending die block sections in alignment with the punches of the piercing units, with punch 260 being positioned in alignment with the centerline through the long sides of the frame and with punches 60 and being positioned in alignment with one another in offset relation with respect to the centerline through the short sides of the frame.

A holddown member 91 is secured to a flattened upper surface 92 on the ram 62 of the cylinder assembly 63, and when the ram 62 moves outwardly to force the punch 60 through the skirt 13, and into the die block opening 870, holddown member 91 moves into position above frame portion 12 (FIG. 4) to positively hold the frame during formation of the hole therein. A passage 95 is provided in die block 85 for receiving the piece of material punched from skirt l3, and the flange 97 of a downwardly inclined chute 96 is secured to die yoke 85 around passage 95. A centrally disposed circular opening 98 is provided in base 22, and a scrap container may be positioned below opening 98 for receiving the punched out pieces from chute 96.

The electrical control means for the above described apparatus is schematically illustrated in FIGS. 6 and 6A-6C. With reference to FIG. 6, the lines of the schematic diagram have been numbered consecutively from top to bottom 1-32 for ease of reference to the diagram. The electrical control means includes a plurality of relays 101116 positioned respectively in

lines

13, 15, l6, 18, 20, 21, 22, 23, 24, 26, 27, 28, 30, 31, 32 and 5. Relay 101 has normally open contacts 1010 in line 1 14 and normally closed contacts 102b in line 30. Relay 102 has normally open contacts 102a and b in circuit with motor 45 (FIG. 6A). Relay 103 has normally closed contacts 1030 in line 15, normally open contacts 103b in line 18, normally open contacts 1030 in line 28, and normally open contacts 103d in circuit with motor 45 (FIG. 6A). Relay 103 has normally open contacts 104a and b connected in circuit with motor 145 (FIG. 6B). Relay 105 has normally closed contacts 105a in line 18, normally open contacts 105b in line 27, and normally open contacts 105a in circuit with motor 145 (FIG. 6B). Relay 106 has normally open contacts 106a in line 20. Relay 107 has normally open contacts 107a in line 20. Relay 108 has normally open contacts 108a and b connected in circuit with motor 245 (FIG. 6C Relay 109 has normally closed contacts 109a in line 23, normally open contacts 10% in line 28, and normally open contacts 1090 in circuit with motor 245 (FIG. 6C). Relay 110 has normally open contacts 110a in line 24. Relay 111 has normally open contacts 111a in line 24. Relay 112 has normally open contacts 1120 in line 5, normally closed contacts l12b in line 13, normally open con tacts 112C in line 29, and normally closed contacts 112d in line 30. Relay 113 has normally open contacts 113a and b in circuit with motor 45 (FIG. 6A). Relay 114 has normally open contacts 114a and b in circuit with motor 145 (FIG. 6B). Relay 115 hasnormally open contacts 115a and b in circuit with motor 245 (FIG. 6C). Relay 116 is a time delay relay and has normally open contacts 1 16a in line 6.

The

metal rollers

56 and 56a cooperate with the metal frame 11 to define a switching means 56b in line 16, which is closed when both

rollers

56 and 56a move into engagement with skirt 13. The metal roller 156 cooperates with metal frame 11 to define a switch 156b in line 21, which is closed when roller 156 moves into engagement with the skirt 13, and roller 156a also cooperates with the metal frame 11 to define a i switch 156a in line 22 that is closed when roller 156 moves into engagement with the skirt 13.

Rollers

256 and 256a also cooperate with the frame 11 to define

switches

256b and 2560 in

lines

26 and 27, respectively.

Motor controllers 117--l19 are provided in lines 2-4, respectively, for controlling the speed of

motors

45, 145 and 245, respectively. Fuses f1-j3 are connected in series in line provided in line 13 for controlling energization of motors 45,

145 and 245 after the flatness sensing micro switches 100a- -100d in line 13 are closed by the flat portion 12 of frame 1 1.

To operate the locating and punching apparatus 10, the power switch 120 is closed to activate indicating light 120a, motor controllers 117119 and the primary of a transfonner 122 in line 7. Relays 1l3-115 are energized through the normally closed contacts 112d and 101b in line 30, and the energization of relays 113115 operates the closure of contacts 113a, 113b, 114a, 114b, and 115a and ll5b FIGS. 7A-6C) to energize

motors

45, 145 and 245 and to rotate the lead screws 29, 129 and 229 in a direction to move the rollers associated with the lead screws to a clearance position. When the rollers are in a clearance position, a limit switch 128 in line 30 is opened to deenergize the relays l13-l 15.

A frame 11 is then positioned on the support structure, with the skirt 13 of the frame positioned outwardly of the rounded surfaces 990' on rough locating members 99. The horizontally disposed midportion 12 of the frame is seated upon the upper surface of die blocks 88, 188 and 288, and if the frame portion 12 is generally planar, the actuators 100 associated with the locating members 99 close switches l00a100d in line 12, to energize flatness indicating means in the form of lamps L1- L4 in lines 9-12, respectively. If all of the lamps L1-L4 do not light, the piece is rejected, but if the switches 100a- -100d close, the circuit is conditioned for actuation of the sensirlg means and this situation is indicated by lamps L1--L4.

Operation of the centering means is initiated by depressing push buttons 123 which energizes relay 101 in line 13, and relay 101 is retained energized by a holding circuit including contacts 101a in line 14. When contacts 101a are closed, a circuit is completed to relays 102-112. Relay 102 is energized through normally closed contacts 103a of relay 103, and when relay 102 is energized, its contacts 102a and 102b (FIG. 6A) are closed to energize motor 45 and move

rollers

56 and 56a outwardly toward engagement with the skirt of the frame 1 1.

When both

rollers

56 and 56a make contact with the skirt l3, switch 56b in line 16 is closed to energize relay 103, thereby opening contacts 103a in line 15 to deenergize relay 102 and short circuit motor 45. When switch 56b is closed, lamp L5 in line 17 is energized to indicate alignment of the frame 1 1 in a first direction.

Energization of relay 103 closes relay contacts 103b in line 18 to energize relay 104 through normally closed contacts 105a and to energize relay 108 through normally closed contacts 109a. Energization of

relays

104 and 108 closes their respective contacts 104a and b and 108a and b in circuit with

motors

145 and 245, and the rollers associated with these mo- .tors are moved outwardly toward engagement with the skirt 13 of the frame 11. When both rollers 156 and 156a move into engagement with the skirt 13, switches 156b and 1560 are closed to energize relays 106 and 107 to close

contacts

106a and 107a in line 20 and thereby energize relay 105. Closing of contacts 106a and 1070 completes a circuit to lamp L6 in line 19. Energization of relay 105 opens contacts 105a to deenergize relay 104 and to short out motor 145 through contacts 1050.

When

rollers

256 and 256a move into engagement with the skirt 13 of the frame 11, switches 2561) and 2560 are closed to energize

relays

110 and 111, respectively. Energization of

relays

110 and 111 closes contacts 110a and 11 1a in line 24 to energize relay 109 and to complete a circuit to lamp L7 to indicate that proper alignment of the frame has been completed. When relay 109 is energized, contacts 109a in line 23 are opened to deenergize relay 108 and close contacts 108C to short out motor 245.

When relays 103, 105 and 109 are energized as described above, contacts 103c 105b and 10% in line 28 are closed to energize relay 112. Relay 112 opens contacts 112b in line 13 to deenergize relay 10l,'and relay 112 is retained energized through a holding circuit including contacts 1l2c and switch 121a in line 29. Energization of relay 112 also opens contacts 112d in line 30 to deenergize relays 1 13l 15.

When relay 112 is energized, contacts 112a in line 5 are closed to energize time delay relay 116 and close contacts 116a in line 6 thereby energizing booster solenoid 121. Booster solenoid 121 opens the switch 121a in line 29 to deenergize solenoid 121, and the energization of solenoid 121 is also utilized to actuate the piercing units 2628 by any suitable means responsive to actuation of the solenoid. For example, the energization of solenoid 121 may actuate an electric motor for operating pumps to provide fluid under pressure to the hydraulic cylinder assemblies. I

When relay 112 is deenergized contacts 112a in line 5 are opened to deenergize the time delay. relay 116, but due to the time delay, the relay 116 retains contacts 116a closed for a period of time to keep the solenoid 121 energized. When the time delay expires, contacts 116a open to deenergize the solenoid 121, it being understood that the time delay relay is of sufficient duration to allow the piercing units to accomplish the hole forming function. The completed piece is then removed and the cycle is repeated.

lclaim:

l. A process for centering and piercing a generally rectangularly shaped member having a depending skirt comprising: placing said member on a support with the skirt thereof being positioned outwardly of at least first and second expansible means, actuating said first expansible means to move abutments thereon outwardly into engagement with said skirt at opposite sides thereof, actuating said second expansible means to move abutments thereon outwardly perpendicularly to the direction of movement of the abutments on said first expansible means into engagement with said skirt at opposite sides thereof to precisely locate said member on said support moving at least a pair of piercing members into and out of hole piercing engagement with said skirt, and removing said member from said support.

2. A process as set forth in claim 1 wherein said member is positioned on said support with said skirt being positioned outwardly of a third expansible means that is actuated simultaneously with the actuation of said second expansible means to move abutments on said third expansible means outwardly parallel with the abutments on said second expansible means into engagement with said skirt at opposite sides thereof.

3. A process as set forth in claim 2 in which the abutments on said first expansible means are movable along a first center line of said member, and wherein the abutments on said second and third expansible means are movable in a direction spaced equally from and parallel with the second centerline of said member.

4. A process as set forth in claim 1 including the step of sensing a flattened portion of said member prior to the actuation of said expansible means.

5. A process as set forth in claim 1 wherein movement of said abutments is terminated in response to engagement of said abutments with said skirt.

6. A process as set forth in claim 1 including the step of reactuating said expansible means to move said abutments out of engagement with said skirt prior to removal of said member from said support. 7

7. A process for centering and piercing a generally rectangularly shaped member having a horizontal portion and a skirt depending therefrom, comprising: placing said member on a support with the skirt thereof being positioned outwardly of at least first and second expansible means, sensing a plurality of spaced locations of said horizontal portions and conditioning said expansible means for actuation only if said locations are disposed in a common plane, actuating said first expansible means to move abutments thereon outwardly into engagement with said skirt at opposite sides thereof to precisely locate said member on said support, moving at least a pair of piercing members into and out of hole piercing engagement with said skirt, and removing said member from said support.

8. A process as set forth in claim 7 wherein said sensing step is performed by sensing each corner of said horizontal portion.

9. Apparatus for providing a plurality of holes in a generally rectangularly shaped member having a depending skirt comprising: support structure; means associated with said support structure for locating said member thereon, said locating means including first, second and third expansible means, said second and third expansible means being parallel and said first expansible means being positioned at right angles with respect thereto, each expansible means having abutments thereon, the abutments on said first expansible means being positioned for movement along a first centerline of said member and the abutments on said second and third expansible means being positioned for movement along respective paths spaced equally outwardly from the second center line of said member, and means for moving the abutments of each expansible means outwardly into engagement with the skirt to center the member relative to the support structure; a plurality of tool means for forming holes in said member; and means mounting said tool means for movement relative to said support structure into and out of hole forming relationship with respect to said member.

10. Apparatus for providing a plurality of holes in a generally rectangularly shaped member having a depending skirt comprising: support structure; means associated with said support structure for locating said member thereon, said locating means including a plurality of fixed guiding members, each guiding member being positionable in one corner of said skirt; a plurality of tool means for forming holes in said member; and means mounting said tool means for movement relative to said support structure into and out of hole forming relationship with respect to said member.

11. Apparatus as set forth in claim 10 wherein said locating means further includes first and second expansible means positioned at right angles with respect to one another, each expansible means having abutments thereon, and means for moving the abutments of each expansible means outwardly into engagement with the skirt to center the member relative to the support structure.

12. Apparatus for providing a plurality of holes in a member including a horizontally disposed portion comprising: support structure; means for sensing a plurality of spaced sections of said horizontal portion to determine whether said sections are disposed in a common plane; means associated with said support structure for locating said member thereon; a plurality of tool means for forming holes in said member; and means mounting said tool means for movement relative to said support structure into and out of hole forming relationship with respect to said member.

13. Apparatus as set forth in claim 12 wherein said locating means includes fixed guiding members on said support structure, said sensing means being associated with said guiding members.

14. Apparatus for providing a plurality of holes in a generally rectangularly shaped member having a depending skirt comprising: support structure; means associated with said support structure for locating said member thereon, said locating means including first and second expansible means positioned at right angles with respect to one another, said first and second expansible means each being defined by a lead screw having oppositely threaded end portions, a slide member movable by each threaded portion of said screws, and an abutment on each slide member engageable with the skirt of said member; a plurality of tool means for forming holes in said member; and means mounting said tool means for movement relative to said support structure into and out of hole forming relationship with respect to said member.

15. Apparatus as set forth in claim 14 wherein said tool means are defined by a plurality of reciprocally mounted piercing elements, and means for moving said piercing elements toward and away from said member.

Claims

1. A process for centering and piercing a generally rectangularly shaped member having a depending skirt comprising: placing said member on a support with the skirt thereof being positioned outwardly of at least first and second expansible means, actuating said first expansible means to move abutments thereon outwardly into engagement with said skirt at opposite sides thereof, actuating said second expansible means to move abutments thereon outwardly perpendicularly to the direction of movement of the abutments on said first expansible means into engagement with said skirt at opposite sides thereof to precisely locate said member on said support moving at least a pair of piercing members into and out of hole piercing engagement with said skirt, and removing said member from said support.

6. A process as set forth in claim 1 including the step of reactuating said expansible means to move said abutments out of engagement with said skirt prior to removal of said member from said support.