The present invention relates to a flange forming drill means for drilling a hole through the side of a pipe or the like and for forming a hole encircling flange, said means comprising: a body, a drive shaft rotatably journalled to the body, a drill rod and a drill bit fitted on the end of the drive shaft, an adjustment member which can be turned around the drill rod to thereby extend forming members beyond the jacket surface of the drill rod, supporting legs capable of supporting the device against the piece to be worked on and which are fitted on the body on either side of the drive shaft in parallel relationship therewith, a feeding nut secured to the supporting legs and which can be opened and closed for removal from and enga>_ ment with a feeding screw mounted on the drive shaft, whereby in the closed position of the feeding nut and with the drive shaft rotating the supporting legs project from the body outwards thus making the projecting forming members, which rotate along with the drill rod, to rise from below the edges of the hole and to form a flange this way.

Such a flange forming drill means is disclosed in US patents 3 592 038 and 3 714 808. That device has proven very useful when it is necessary to form a flanged hole through the side of a pipe e.g. for connection of a branch.

The object of this invention is to further develop the said device, so that after the drilling operation shifts, without interruption in the operation, automatically to the flange forming step.

This object is achieved with the above-mentioned type of device in such a manner that the feeding nut is arranged to close automatically by means of link mechanism when the supporting legs have moved a certain distance into the body. Thus, an essential feature in the invention is the utilization of the movement of the supporting legs' for automatic closing of the feeding nut.

Since also the forming members must be extended from the drill rod, after the hole has been drilled, simultaneously with the closure of the feeding nut, according to a preferred embodiment of the ivention, this has been arranged to happen automatically in such a manner that to the supporting legs have been secured brake bits at such a level that they respond to the adjustment member when the supporting legs have moved sai.d certain distance into the body, whereby the brake bits turn the adjustment member with respect to the drill rod and effect the extension of the forming members substantially simultaneously with the closure of the feeding nut.

In the following specification the invention is illustrated in more detail with reference made to the accompanying drawings, in which:

fig. 1 shows a device of the invention in side view and partially sectioned in a position where the hole drilling is finished and where the automatics according to the invention is ready to work.

^' fig. 2 shows a device of figure 1 in a condition in which the automatics have worked after the drill means has been urged a small distance downwards from the position of figure 1,

fig. 3 is a section taken along the line III-III in figure 1,

fig. 4 is a section taken along the line TV-IV in figure 1, and

fig. 5 is a section taken along the line V-V in figure 2.

The device comprises a body 1 to which is rotatably journalled a drive shaft 2 with a toothed gear 3 in its upper end rotated by means of a drive motor, not shown. To the lower end of the drive shaft 2 is connected a head portion 4 of the drill means, comprising a drill rod with its drd.ll bit 5, through the drill rod crosswise extending forming pins 6 as well as an externall'

smooth protective shield 7 enclosing an adjustment cone which • can be turned around the drill rod thus extending the pins 6 so as to project from the drill rod or to be retracted into the drill rod, as described in more detail in the parallel patent application No. The shield* 7 is in working " contact with the adjustment cone therein, so that the forming pins 6 can be retracted and extended by turning the shield 7 with respect to the drill rod 5. Turning of the protective cone 7 is possible after lifting said protective cone 7 slightly upwards in axial direction.

To the body 1 on either side of the shaft 2 there are slidably journalled supporting legs 8 whose hook-shaped ends 9 can be brought to engage the piece 10 to worked for supporting the dri I means with respect to said piece to be worked on. Supporting legs 8 are fitted with brake bits 11 which, after the hole has been drilled through the piece 10 to be worked on, lean against the conical lower face of the protective shield 7. With continued downward pressing of the drill means, the brake bits 11 lift the shield 7 in axial direction upwards, and thus, by the action of the friction, upon rotation of the device,between the brake bits 11 and shield 7, the protective shield 7 together with associated adjustment cone turns with respect to the drill rod 5 and effects the projection of the forming pins 6 from the rod 5, as depicted in figure 2.

Upper ends of the supporting legs 8 are secured to each other by means of a plate 12 which carries the feeding nut 13 which, on the other hand, can be brought to contact with a feeding screw 14 provided on the shaft 2. Nut 13 consists of two halves turning around an axis 15 and a spring 24 urges the halves of nut 13 towards a closed position, i.e. to engagement with the screw 14. The ends of the nut 13 halves, disposed opposite to each other relative to the axis 15, are designed as counter members for a cam portion 16, which in the first position depicted in figure 4 retains the halves of nut 13 open or disengaged from the screw 14 and in the second position shown in figure 5 allows the spring 24 to urge the halves of nut J_3

together and into engagement with the screw 1 . A latch 25 connected with the cam portion 16 keeps the nut closed and a spring 26 connected with an arm 17 urges the cam portion 16 towards said second position (figure 5) for forced closure of the nut 13. By means of the arm 17 the cam portion 16 is in working engagement with a pivotable lever 18 whose ends are designed as gripping means 19 by which the lever 18 is manually pivotable to the first position (figure 4) , in which the cam portion 16 opens the feeding nut 13. The cooperative counter faces of the cam portion 16 and feeding nut 13 are so designed that under the combined effect of spring 24 and spring 26 the cam portion 16 and lever 18 tends to turn in forced manner into its second position in which the nut 13 is allowed to close and the latch means 25 keeps it that way. For retaining the cam portion 16 and lever 18 in their first position (figure 4) there is fitted a retainer pin 20 which is longitudinally slideable in a guide means 21 connected with the body 1 and urged downwards by means of a spring 22 in such a manner that the limiting flange 23 responds to the top surface of the plate 12. With the supporting legs 8 in the figure 1 position, _' the retainer pin 20 keeps, by means of lever 18 and cam portion 16, ' the feeding nut in the position depicted in figure 4. When the drill means urged still further down from the position of figure 1, the plate 12 associated with the supporting legs 8 lifts the pin 20 upwards with respect to the body 1, whereby the lever 18 is released and the feeding nut 13 closed into the position of figure 5. Thus, the rotating feeding screw 14 and feeding nut 13 begin to push the supporting legs 8 out of the body 1. The body 1 pulls therealong the rotating drill bit with projecting forming means 6 upwards from the work piece 10, the edges of the hole bending upwards and forming a collar flange.

It is important to appreciate that in the device according to the invention the movement of the supporting legs 8 is used for automation of two different functional steps, Pirst of all, with the shield 7 responding to the brake bits 11, the forming

I pins 6 project from the drill rod and, secondly, almost

simultaneously thereafter the pin 20 loosens itself from the lever 18 and the feeding nut 13 closes. Both actions occur substantially simultaneously after drilling of the hole, when the drill means is pressed still a slight distance downwards with respect to the supporting legs 8.