US2344053A

US2344053A - Automatic drilling machine

Info

Publication number: US2344053A
Application number: US440745A
Authority: US
Inventors: James S O'callaghan
Original assignee: Individual
Current assignee: Individual
Priority date: 1942-04-27
Filing date: 1942-04-27
Publication date: 1944-03-14
Anticipated expiration: 1961-03-14

Description

Mam! 19447 J. s. CCALLAGHIAN 2,344,053

AUTOMATIC DRILLING MACHINE Filed April 2'7, 1942 V 4 Sheets-Sheet, 1

JLT" W (9kg znne ntor 9 atiomeu March 14, 1944. 5. O CALL AGHAN 2,344,053

AUTOMATIC DRILLING MACHINE Filed April 27, 1942 4 Sheets-Sheet 2 Gttomeg 4 Sheets-Sheet 5 Summer )3.

March 14, 1944. J.S. O'CALLAGHAN AUTOMATIC DRILLING MACHINE Filed April 27, 1942 i LEM March 14,1944. 2,344,053

J. 5. OCAl- LAGHAN AUTOMATIC DRILLING MACHINE Filed April 27, 1942 4 Sheets-Sheet 4 3maentor (1 torneg Patented Mar. 14, 1944 UNITED STATES PATENT OFFICE 6 Claims.

The invention relates to an improvement in automatic drilling machines, and one essentially adaptable for drilling a hole, or holes, in small objects.

The result sought for by the invention is a full automatic machine, or one which may easily be made full automatic.

The drilling machine constituting my invention shows the way in which the objective result above referred to may be secured, and consists of a combination which is characterized and attained by an association of elements, or parts, having such joint and co-operative action as to effect the objective end.

An example of a combination constituting my invention Will now be described in the light of the drawings, and afterwards claims made therefor in the light of such description.

In the drawings:

Fig. 1 is a side elevation of the machine.

Fig. 2 is a front elevation of the top structure ofthe machine shown in Fig. 1.

Fig. 3 is a top plan of the machine.

Fig. 4 is a section on the line 4-4 of Fig. 1.

Fig.5 is a section on the line 55 ofFig. 2.

Fig. 6 is a section on theline 6-6 of Fig. 1;

Fig. 7 is a cross section of certain of the working parts, later to be referred to, when in dormant position.

Fig. 8 shows especially the same elements as Fig. 7, excepting that the elements have been activated to assume an operative or working position.

Fig. 9 is a plan of the part, or object, drilled by the machine.

7 Fig. 10 is a cross section on the line Ill-J of Fig. 9.

Fig. 11 is a cross section of the mounting for the power drill hereinafter to be referred to.

Fig. 12 is a side elevation of various parts giving adjustability to the clamping head.

Fig. 13 is a plan of the clamping head shown in Fig. 12 disassoclated from its adjustable parts; and

Fig. 14 is a plan of the clamping head with the adjustable parts applied to it.

Referring to the drawings-! represents the frame of the machine having a top 2 with a vertical opening 3 through it at about the center of the table.

Located upon the top 2 are ways 4, 4, within which runs a slide having a forked fore end 6. This forked fore end of the slide is adaptable duced between the Ways 4, 4, forward of the forked end of the slide, so that the object will be moved by the slide to a determinate centralized position over the opening in the table top where the object is held clamped. The slide is moved by a lever I pivoted at 8 to the frame of the machine. This lever is under the control of a spring In and cam H. roll l2 held in constant engagement with the peripheral edge of the cam by the action of the spring I0. The cooperative action of these parts is such that the spring will act upon the lever to move the slide forward an amount sufiicient to localize the object over the opening in the table when so permitted by the cam, dependent upon the turned position thereof. As the cam turns another portion of its cam surface will act upon the lever to reverse the position of the slide. Thus a to and fro movement of the slide is obtained. The cam H is arranged upon a cam shaft l4 journalled to turn in supports [5 fixed to the frame of the machine.

Fixed to the top 2. by bolting, or otherwise, is a piece [1. This piece spans the opening in the top, leaving a passage l8 through the piece through which the object a to be drilled may pass. The head IQ of the piece overhanging the opening in the top forms a clamp member against which the object is held clamped, When positioned over the opening in the top, by the operation of the slide.

Bolted or otherwise fastened to the under side of the top 2, in circumscribed relation to the opening in the top, is an annular head 20 from which depends a tubular boss 2| with a vertical opening 22 through the head and boss. This opening is in axial alignment with the opening 3 in the top, but is of larger diameter than that of the opening in the top. Slidably contained within the openings 3 and 22 is a sectional plunger comprising a section 24 slidable within the opening 3 in the top, and

sections

25 and 26, respectively, slidable within the openin 22 in the top. Arranged upon the section 24 of the plunger and interposed between the section 25 and the under side of the top 2, is a coiled spring 28. Interposed between, and connected respectively, to the

sections

25 and 26 of the plunger, is a coiled spring 29. Projecting centrally from the top free end of the section 24 ofthe plunger is'a pin 30 adaptable to enter the opening 22 through the center of the object a when the object is positioned over the opening in the top as aforesaid. The section 26 of the plunger protrudes beyond to engage the object a to bedrilled, when introthe boss 2| in which it slides, and. the end of the The lever bears a cam plunger section, so protruding, has hearing engagement against a lever 32. This lever is pivoted to the frame at 33. The lever bears upon its free end a cam roll 38 which engages the working surface of a cam 35 on the shaft M. The parts are so co-ordinated that when the plunger is in its inactive position, as shown in Fig. '7, both springs 28 and 29 are under tension, the cam roll on the arm 32 being then yieldingly maintained by the springs in contact with the inactive portion of the cam. This action is initially obtained by th spring 28 which is then distorted to exert a force exceeding that obtained by the distortion of the spring 23. At this same time the pin borne by the section 24 of the plunger will lie substantially fiush with the upper surface of the top 2 in position to enter the opening 1) in the object a when the plunger'isactivated to move vertically upward. The upward movement or advance of the plunger follows upward movement imparted to the plunger section 128 by the cam 25. As the plunger section 26 ismoved upward by the cam, like movement is 'yieldingly applied to the plunger sections 24 and through the spring 25 and the pin 39 on the free end of the section 24 will enter the opening b in the object a to be drilled, thereby assisting in centralizing its position. At substantially this same-time, but following the centralizing cf the object by the pin, the object will be held clamped between the end of the plunger section 2e and the head 19 on the top 2. The clamping of the object is in fact yieldingly effected owing to the presence of the spring 28 between the plunger sections 25 and 2G. tracted as the plunger is moved upwardly, and thus becomes the active force for yieldingly activating the

plunger sections

26 and 25 for obtaining the centralizing and clamping of the object as aforesaid, thereby allowing for extremely quick action of the operating parts, and eliminating danger of breakage.

During the upward movement of the plunger for effecting the clamping operation the spring 28 will become highly compressed so that when the plunger is relieved of the activating force exerted by the cam which lifts it, it-will be returned to its normal position of rest by the spring 28. The spring 28 will then act to hold the spring 29 under a slight degree'of contraction in order to maintain engagement of the intermediate parts with the cam and eliminate all lost motion, thus ensuring that all the parts of the plunger will become instantly active when the plunger section-25 is again raised by the operation of the cam.

During the time that the objectis held clamped holes are drilled in it. For this purpose there is mounted upon the top 2 a set of power drills 40. These drills are preferably electrically driven. Each of these power drills has, afiixed to its side, a housing 42. The housing may be secured to the body of the power drill by straps 43 connecting with the housing and passed around the body of the drill. Each of these housings is mounted upon a cradle 45 fixed to the top 2. The several power drills with aflixed housings are set upon their cradles in an inclined position and with such placement that the ends of their drills 65 will normally lie contained within the clamping head 19, this head being provided with inclined openings 41 within which the ends of the drills are recessed. The inclination of these openings is such that when the drills are proiected downwardly from the openings, and the drill rotated,

This spring will become highly co-n- I er is relieved. means of an arm extending over it. One end of this arm is pivoted to a standardtl on they will severally drill the requisite holes in the clamped object.

During the operation of the machine the power drills, kept active, rotating the drills 46 borne by them, are moved forward in their entirety for drilling the holes in the clamped object in the following manner.

Each of the power drills is slidably mounted upon its cradle through a dovetailed connection i9 between the top of the cradle and the bottom of the housing. The bottom of each housing is provided with a rack 50. Engaging this rack for the purpose of moving the housing and power drill to which it is attached, back and forth, is a pinion-52 fixed to the shaft 53 journalled to turn within the sides of the cradle and provided outside the cradle with a crank arm 54 by which it may be turned. These crank arms are collectively under the control of a disk 55 through links 56 pivotally connected, respectively, to the crank arms and to the disk. The disk 55 is provided with a sleeve 58 slidable upon the boss 2|. Pivoted to the side of the sleeve is an arm 59. The opposite end of this arm is pivoted to a'lever 60 at'Bl. This lever is pivotally secured at 62 to the side of the frame. The :lever bears a cam roll 64 which is held in engagement with a cam 65, on the cam shaft 14, by means of a tension spring 66 interposed between the end of the lever and the top 2. This spring is in a state of tension, holding the cam roll 64 in constant engagement with the cam 65, and accordingly, through the connecting mechanism controlling the vertical position of the disk 55. When the disk is lowered, the power drills, through the intermediate connections which include the racks and pinions, will be projected forward for boring the :holes in the clamped object. Following further turning of its controlling cam 65 the disk will be raised, retract- .ing the power drills but leaving the ends of their drills 46 recessed within the head 19 of the clamping block.

After the drilling of the holes in the object a and its release from the parts holding it clamped, it is then subjected to the action of compressed --air. The air enters by wayof a pipe 68 which connects with branches-69, 10, and H.

These branches are so arranged as to direct the air acts to blow the object along the table to a position where it is directed by a guide'12 to pass through an opening 13 in the table and thence through a chute M'by which its passage is further directed. Compressed air which enters 'to :pass through the pipe 58 enters the machine by wayof .a pipe 1-8 which connects with the inlet end of a valve T! to the outer end of which pipe 68 is connected. The valve 1-] :is one of a com- :mon type in which its valve is a spring controlled valve normally held closed but which may be opened by a plunger 18 which, when depressed, will open the valve, but permitting its immediate closure when thepressure upon the plung- The plunger is depressed .by

the frame of the machine and the other end of the arm is arranged to be struck by a cam .roll .82 on a cam 83 on the cam shaft [4 asthe cam 83 is rotated by the rotation of the shaft.

As the cam is rotatedits cam roll will strike the arm 80 and momentarily depress the plunger, thereby providing for a momentary expulsion of compressed air, which is sufficient to expel the object from the table;

The cam shaft I4 is turned by means of an electric motor 84 through driven parts under the control of a foot treadle 85. To this end the electric motor is provided with a clutch 86 of common type normally inactive. The driven section of the clutch is provided with a shaft 81, and the clutch is rendered active for turning the shaft 8'! by pressure of the engaging end 88 of the foot treadle against the end of this shaft. When the foot is removed from the treadle the clutch will be thrown out. Arranged upon the shaft 81 is a pulley 89 around which renders a belt 96. This belt is in driving connection and a pulley 9| on a shaft 92 suitably journalled to turn on the frame of the machine. The shaft is provided with a Worm 93 which engages a gear 94 on the cam shaft l4. Thus the cam shaft is turned by the electric motor as long as the parts are rendered active by the depression of the foot treadle.

The various cams are disposed upon the cam shaft 54 in such order that they will severally perform their various functions in proper timed sequence to effect the resultant action attained by the machine, which includes the deposit of the article to be drilled in precise position to be clamped, the clamping of the object, the drilling of the object, and its ejection from its clamped position, the several operating parts being returned to their initial positions dependent upon the turned positions of the respective cams. All these operations take place during a single rotation of the cam shaft. In practice this rotation takes a little over a second, which means that each object is positioned, clamped, drilled, and ejected from the table, in a little over a second.

In order that the object, or article, to be drilled may be deposited over the opening in the table in the precise position it is to be clamped, the cam I l is so cut that it will operate through the lever l to move the slide 5, which positions the object, with a relatively rapid movement at the beginning of its throw, but with slow movement as approach is made to the position where the object is to be left, so preventing momentum displacing the object, the object remaining in the precise position at which it is left by the slide.

If by chance the machine lacks an object to be clamped during a phase of its operation then, in

such case, the plunger might be raised so far that the drills, then projected and operated, might engage the end of the plunger section 24 and disfigure it. This action, however, is prevented by a guard 5 borne by the plunger section 25. This guard in the normal working of the machine, when the plunger is raised, and the object held clamped, will not engage the under side of the top 2, but will stop just short of its under surface so as not to interfere with the proper clamping of the object. If there is no object to be clamped then this guard, on the upward stroke of the plunger, will engage the under side of the top and so prevent the section 24 of the plunger from being raised but a slight distance more than it would be raised if it were engaging an object for clamping it, thus ensuring that the drills when projected will not engage its top end.

The drills will strike the clamped object at points radially removed from the axial center of the object, dependent upon the vertical adjusted position of the object with relation to the drills. Accordingly, in order that variation may be .obtained in the location of the points where the drills first engage the clamped object away from its axial center, a vertically adjustable clamping head is provided against which the object is clamped by the operation of the plunger. This adjustable head has a set of adjustable pins 91 triangularly arranged passed through it. .The

head It! then no longer provides the clamping member against which the object is held clamped by the operation of the plunger but rather its adjustable pins 91; the part I9 of the clamping block being raised so far that the pins may provide this clamping member. The vertically ad'- justed position of these pins provides variation in the distance away from the axial center of the object, when clamped, that the drills will engage the top surface of the object. The pins 5'! are borne by a plate 98 adjustably secured to the head l9 by adjusting screws 99 and the adjustment is secured by the introduction of on or more shims I99.

I claim:

1. In an automatic drilling machine for drilling holes in objects held clamped in successive order, the combination comprising, the frame of the machine with top having an opening in it, a clamping head in fixed connection to said top and bridging said opening in spaced relation thereto, a slide by which the objects to be drilled will be successively deposited over said opening beneath said clamping head, means for reciprocating said slide including a cam, a reciprocating plunger including a part movable through the opening in said top for clamping said objects when deposited as aforesaid and for releasing them as said plunger is reciprocated, means for reciprocating said plunger including a cam, a power drill arranged upon said top in position to drill said objects successively held clamped when said power drill is projected from a retracted position, means for projecting said power drill and for effecting its return including a cam, means for removing said objects each from its clamped position after the drilling and release thereof including a cam, a common shaft bearing all of said cams, means for arranging the cams upon said shaft whereby they will operate successively in proper timed sequence during a single rotation of said shaft, and means for turning said shaft.

2. In an automatic drilling machine for drilling holes in objects held clamped in successive order, the combination comprising, the frame of the machine with top having an opening in it, a clamping head in fixed connection to said top and bridging said opening in spaced relation thereto, a slide by which the objects to be drilled will be successively deposited over said opening beneath said clamping head, means for reciprocating said slide including a cam, a reciprocating plunger including a part movable through the opening in said top for clamping said objects when deposited as aforesaid and for releasing them as said plunger is reciprocated, means for reciprocating said plunger including a cam, a power drill arranged upon said top in position to drill said objects successively held clamped when said power drill is projected from a retracted position, means for projecting said power drill and for effecting its return including a cam, a common shaft bearing all of said cams, means for arranging the cams upon said shaft whereby they will operate successively in proper {timed sequence during a single rotation of said ,shaft,.and'means 'for turningsaid shaft.

3. In a drilling machine .for objects .held

clamped in successive order, the combination comprising, a frame having a top with opening :in it, a clamping head afiixed to said top and arranged to bridge said opening, means whereby said objects will be successively deposited over said opening beneath said clamping head, areciprocable plunger operable through said opening in the top for clamping said objects against said head when deposited as aforesaid, a boss aflixed to said top within which said plunger is reciprocable, means for reciprocating said plung- -er,a'plura1ity of power drills mounted upon said top and set in position to simultaneously drill said objects in the successive order of their clamping upon the projection of said drills from a retracted position, means for slidably mounting :said power drills whereby they will be projected rand-retracted, mechanism for controlling the projected or retracted position of said power drills :including 'for each of said power drills an oscillatory crank arm, means for oscillating said crank arms including a reciprocating disk having pivsaid head when deposited as aforesaid, said plunger comprising a plurality of sections, one a top section adaptable to pass through the opening in said top, the others, an intermediate section ,and a bottom section each of larger diameter ;than the opening through said top, a spring interposed between and connected, respectively, to said intermediate and bottom sections, a spring interposed between said intermediate section and said top, means aifixed to said top within which said plunger is reciprocable, and means for reciprocating said plunger whereby it will intermittently engage and assist in the clamping of said objects as "they are successively deposited over the opening in the top and be returned to an inactive position.

5. In a drilling machine for objects held clamped in successive order, the combination comprising, a frame having a top with opening in it, a clamping head affixed to said top and arranged -to :bridge'said opening, means whereby said objects will be successively deposited over said opening beneath .said clamping head, a reciprocable plunger operable through said opening in the top for clamping said objects against said head when deposited as aforesaid, said plunger comprising a plurality of sections, one a top section adaptable "to pass through the opening in said top, the others, an intermediate section and a bottom section each of larger diameter than the opening through said top, a spring interposed between and connected, respectively, to said intermediate and bottomsections, a spring interposed between said intermediate section and said top, a guard borne by said intermediate section constructed and arranged to engage said top when said top section of the plunger rises unduly through said opening in the top during the projection ofthe plunger for lack of an object to be clamped, means afiixed to said top within which said plunger is reciprocable, and means for reciprocating said plunger whereby it willintermittently engage and assist in the clamping of said objects as they are successively deposited over the opening in the top and be returned to an inactive position.

,6. .In a drilling machine for objects held clamped in successive order, the combination comprising, a framehaving a top with opening in it, a clamping head afiixed to said top and arranged to bridge said opening, said clamping head having a plurality of adjustable pins passed through it into the space above said opening, means for adjustably fixing said pins, means for depositing the objects to be drilled in successive order over said opening and beneath said pins of the clamping head, and a reciprocable plunger operable through the opening in said top and engaging each object deposited as aforesaid whereby the object so deposited will be held clamped between said pins and the end of said plunger.

JAMES S. OCALLAGHAN.