US1930013A - Multiple drilling machine - Google Patents

Description

Oct. 10, 1933. c. L. MAHREN 4 4 1,9

' IULTIPLB DRILLING ucnxma Filed Oct. 17. 1932 2 Sheets-Sheet 1 lNvNTOK a mchh n Patented Oct. 10, 1933 MULTIPLE DRILLING MACHINE Carl Leonard Mahrn, Hoganas, Sweden, assignor to A.B. Coma Multiple Drill Machine Co., Malmo, Sweden, a corporation of Sweden Application October 17, and in Sweden 3 Claims.

The present invention relates to a multiple drilling machine especially for drilling brush heads and the like and having drills provided with screw-shaped stems rotatable by means of a reciprocable plate which is in engagement with said stems.

The object of the invention is to provide a multiple drilling machine which is capable of drilling, in one single operation, a practically unlimited number of holes the axes of which are inclined towards each other at any angle.

According to the present invention each drill stem is adapted to be fed in the direction of its own axis towards a fixedly positioned work piece said drill stems forming any angle with each other.

The invention is illustrated in the accompanying drawings, in which Fig. 1 is a vertical cross sectional View of an embodiment of the machine according to the invention, and

Fig. 2 is a vertical longitudinal sectional view of said embodiment of the machine.

While the machine shown in the drawings is a vertical one, it should be noted that the invention is not limited to said type of machines and, generally, horizontal embodiments should be preferred for reasons stated below.

In the embodiment of the machine shown in the drawings, 1 is a frame-work, four vertical columns 2 being secured to the upper surface of said frame-work. At equal height above said upper surface of the framework, the columns are provided with offset portions 4 forming transitions to the upper portions 3 of the columns, said upper portions having a smaller diameter than the lower portions of said columns 2. On the offset portions 4 a guide plate 5 is supported and clamped against said offset portions by means of nuts 6 provided on a screw threaded portion of the columns.

' The guide plate 5 is provided with a plurality of perforations the axes of which are parallel as viewed in the section according to Fig. 2 but inclined towards each other as viewed in the sec tion according to Fig. 1.

At th centre of one of the longitudinal sides of the frame-work 1 a vertical rod '7 is positioned, a feed lever 8 being pivoted to the upper end of said rod 7. Above the guide plate 5 said lever 8 is provided with a horizontal hole, and upon a pivot 9 in said hole a feed breast 11 is supported by means of perforated lugs 10, said breast thus normally being positioned at a distanee above the guide plate 5. At each corner the feed breast 11 is provided with a vertical hole, and by means of said holes it is guided upon the upper portions 3 of the columns 2. In the embodiment shown, both the guide plate 5 and the feed breast 11 are bent in the section according 1932, Serial No. 638,243, October 26, 1931 to Fig. 1 the concave side facing downwards. However, this is not a necessaryfeature but said members may also be fiat or have any other suitable shape.

A rectangular frame 12 has a hole in each of its corner portions said four holes forming guide members to the frame 12 upon the columns 2, said frame thus being reciprocable in a vertical direction on the columns whilemaintaining its horizontal position. To the frame 12 a substantially rectangular plate 14 is secured, said plate being provided with a plurality of slots 15 extending transversely to the frame 12. The slots may also be formed by mounting bars transversely to the frame, said bars forming slots between them, or in other suitable ways.

At the middle of each of the shorter sides of the frame 12 said frame is provided with a horizontal arm 12a carrying a horizontal crank arm 16, a connecting rod 17 being rotatably mounted upon said crank arm 16. Each of said connecting rods is rotatably mounted, at its opposite end, upon another crank arm 18, said crank arm 18 being in turn eccentrically mounted upon a fly Wheel 19. i The fly wheels 19 are mounted upon opposite ends of a shaft 20 mounted longitudinally of the frame-work 1 in bearings 22 provided in the short walls of the frame-work 1, and within said frame-work a belt pulley is secured to said shaft 20.

A plate 23 serving as a drill guide is connected to the upper surface of the frame-work 1 by means of screws 24 in such a manner as to form a suitable space between said upper surface and the lower surface of the drill guide 23. Similarly to the guide plate 5, the drill guide 23 is provided with perforations to the same number as those provided in said guide plate 5, said perforations of the drill guide being parallel as viewed in the section according to Fig. 2 but inclined towards each other in the section according to Fig; 1. Beneath the drill guide 23 a disc 25 of wood or other soft material is tenoned into the upper surface of the frame-work 1, the joint preferably being effected in such a manner as to make the disc 25 and adjacent portions of the upper surface form a flat surface.

In each perforation of the guide plate '5 a pin 26 is provided surrounded by a screw spring 27 adapted to maintain the upper end 28 of said pin 26, which is preferably rounded, in permanent contact with the feed breast 11 reciprocable in a vertical direction above the guide plate 5.

To the lower end of each of the pins 26 projecting from the lower side of the guide plate 5 a metal strip 29 twisted likea screw is connected, said metal strip extending through a slot 15 of the plate 14 and shaped as, or provided with, a drill 30 at its lower end, said drill preferably being in the form of an anger but provided with two edges. so as to enable it of boring in both directions of rotation. Each drill 30 extends into one of the perforations of the drill guide 23, the work-piece 31 being positioned beneath said drill guide 23 and the position of said work-piece being determined by adjustable guiding devices, such as screws 32.

The operation of the machine is as follows:

A work-piece 31, such as a brush head'whichv is to be provided with a number of perforations or bores not exceeding the number of perforations of the guide plate 5 and the drill guide 23, is positioned upon the disc 25 the under side of said brush head facing upwards. Here the feed lever 8 ought to be in raised position so as to allow the feed breast 11 to permit the springs 27 to keep the drills raised to such an extent as to enable the Work-piece, 31 to he introduced beheath the lower ends of the drills. On the other hand a stop or the like should be provided limiting the upwards movement of the feed breast 11 in order to prevent the pins 26 and the drills 30 from being pulled out of their perforations in the guide plate 5 and the drill guide 23 respectively.

By a belt passing around the belt pulley 21, driving power is transmitted from a source of power of any kind, such as an electric motor, to the shaft 20, said shaft together with the fly wheels 19 thus being rotated in one direction or the other. Hereby the connecting rods 17 will cause the frame 12 guided upon the columns 2 to reciprocate in a vertical direction, and since the slots 15 of the plate 14 are only slightly wider than the smallest, dimension of the strips 29 each strip, 29 together with its drill 30 is caused to rotate in one direction when the frame 12 is moving upwards and in the other direction when said frame 12 is moving downwards. The speed of rotation is dependent partly upon the speed of reciprocation of the frame 12 and partly upon the pitch of the screw line of the strips 29.

By a suitable pressure exerted upon the feed lever 8 in a downwards direction the drills are forced into the work-piece 31 to the extent desired the drills hereby cutting in both directions of rotation. If the perforations extend all through the work-piece the soft disc 25 prevents the drills from being broken when their extreme ends project beyond the work-piece.

When the boring operation is finished the feed lever B is raisedthe drills 30 then being extracted from the bored holes by the action of the springs 27 and again raised into their upper position. The work-piece 31 is removed-from the machine and then another work-piece may be introduced into the machine and bored.

It is evident that every desirable direction and position of the perforations of the work-piece may be obtained within very wide limits by changing the guide plate 5, the drill guide 23, the plate 14, and, if necessary, the feed breast 11. It is not necessary, of course, that the drills are parallel in the section according to Fig. 2 but, if desired, they may be inclined towards each other also in said section the only provisions being that the slots 15 of the plate 14 be directed in a manner allowing the reciprocation of the plate 14 without breaking the strips or spindles 29 and that the bending of the feed breast 11 be suitable for the purpose. Thus also perforations or bores which are inclined towards each other in the section according to Fig. 2, such as the perforations at the ends of several types of brushes, may bebored simultaneously with the other perforations. Generally, it is evident that an unlimited number of variations of the position, direction and number of the perforations or bores may be cfiected only by changing the parts mentioned above, or some of said parts, and by performing corresponding alterations of the number and position or the drills.

In the case of horizontal machines the advantage is gained that borings and the like accumulating upon the drill guide 23 in a vertical machine drop to the ground. In this case, it may also be advantageous to design the machine in such a manner as to make the under side of the work-piece visible during working whereby it may easily be ascertained whether a drill has become broken or otherwise made useless. If so, the machine is stopped and then the useless drill is easily replaced.

In order to prevent losses of lubrication materials and to protect against splashes of such material the machine may be provided with a protecting casing enclosing the machine above the frame-work and being provided with slots necessary for allowing the movements of projecting movable parts, such as the arms 12a.

The design of the machine may be varied in various manners within the limits of the invention, and accordingly the invention should not be considered to be limited to the embodiment shown in the drawings and described above, said embodiment forming an example only.

What I claim and desire to secure by Letters Patent is:

1. In a multiple drilling machine, drills, spindles provided on said drills, said spindles being screw-shaped, inclined towards each other and adapted to be fed longitudinally, and a plate provided with slots engaging said spindles and adapted to be reciprocated in order to rotate said spindles.

2. In a multiple drilling machine, drills, spindles provided on said drills, said spindles being screw-shaped, inclined towards each other and adapted to be fed longitudinally, pins provided on said spindles at the end opposite to the drills, a guide plate stationarily positioned and provided with perforations, said pins being rotatably and displaceably mounted within said perforations, springs actuating said pins in a direction outwards from said guide plate, and a plate provided with slots engaging said spindles and adapted to be reciprocated in order to rotate said spindles.

3. In a multiple drilling machine, drills, spindles provided on said drills, said spindles being screw-shaped, inclined towards each other and adapted to be fed longitudinally, pins provided on said spindles at the end opposite to the drills, a guide plate stationarily positioned and provided with perforations, said pins being rotatably and displaceably mounted within said perforations, springs actuating said pins in a direction outwards from said guide plate, a feed breast, a feed lever connected to said feed breast, said feed breast being adapted to be reciprocated by means of said feed lever in order to feed said pins longitudinally against the action of said springs, and

a plate provided with slots engaging said spindles .i

and adapted to be reciprocated in order to rotate said spindles.

CARL LEONARD MAHREN.

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