US3550480A

US3550480A - Radial drilling machine

Info

Publication number: US3550480A
Application number: US755985A
Authority: US
Inventors: Hellmut Muller
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-08-28
Filing date: 1968-08-28
Publication date: 1970-12-29
Anticipated expiration: 1987-12-29

Description

Dec. 29, 1970 H. MULLER RADIAL DRILLING MACHINE Filed Aug. 28, 1968 l I l L I I INVENTOR H ELLMUT m u LLPEK United States Patent 3,550,480 RADIAL DRILLING MACHINE Hellmut Miiller, 91 Esslinger Strasse, 731 Plochingen (Neckar), Germany Filed Aug. 28, 1968, Ser. No. 755,985 Int. Cl. B2311 39/12 U.S. Cl. 77-28 7 Claims ABSTRACT OF THE DISCLOSURE A radial drilling machine includes a base frame and a vertically extending column of circular cross-section mounted for turning in the base frame and for movement up and down therein. A clamping arrangement is provided which can be clamped to or'released from the column to permit turning and which slides up and down in the frame while engaging a guide which prevents it from turning around the axis of the column. The top of the column carries a cantilever. arm mounted on rollers for horizontal back and forth movement with a boring head at one end and a motor and gearing at the other.

The invention is concerned'vvith a radial drilling machine and more particularly with a machine which has a vertical column with a circular cross section supported or a base frame so as to be rotatable and around its vertical axis and movable up and down. Radial drilling machines of the category characterized above and already known per se are less expensive in their construction than other known comparable arrangements which have a column rigidly and unrotatably supported on the said base frame and having a roller box rotatably arranged on the said column. However, these known arrangements have the disadvantage that the column, whilst moving up and down, may turn round so that the relative position in a horizontal plane between the tool and the work piece may be lost. However, with these machines to guide the column so as to render any rotatory motion impossible, would prevent the rotatory motion of the column and disadvantageously influence the function of the mechanism.

It is, therefore, an object of the present invention to avoid the above drawbacks and to reduce building expenses for the machine in question.

To obtain this, another object of the invention is to provide a section of that part of the column which is accommodated within the base frame to be'embedded in a holding device that surrounds partially at least the column and that is guided for an up and down movement along a vertical guide by means of a suitable extension and that can be rigidly locked with, and unlocked from, the column.

Yet another object of the invention is to provide a r machine of the aforesaid kind which allows on the one hand to go up and down with the column and to thereby maintain the exact relative position and on the other hand to selectively lock the column with the said base frame or make it rotatable about its longitudinal axis.

Another object of the invention is to obtain an easy rotation of the column without using constructive elements that are too costly.

A further object of the invention is to provide a machine of the kind here in question with which cantilever arm carries on its one end the boring head and on its other end the driving motor andif necessary-the gear to be interposed between the motor and the boring head. With cantilever arms constructed in the usual manner that have their weights unevenly distributed, it is possible that the column and the cantilever arm so disadvantageously presses against that part of the supporting frame "ice which has to bear the column that the relatively high pressure components and the high frictional forces might disturb the rotatory movement of the column unless expensive antifriction bearings are used. This drawback is eliminated by the present invention because the distribution of weights obtained in the above described way according to the invention results in almost equal loads on both ends of the cantilever arm, whereby a unilateral stress or load is avoided at the point where the column is supported by the base frame.

These and other objects, features, and advantages of the present invention will become further apparent from the following detailed description thereof, particularly when the same is read with reference to the accompanying drawings, in which:

FIG. 1 is a first form of embodiment of a radial drilling machine according to the invention in a schematical side view and in a partly vertical section,

FIG. 2 is a section taken along the line II--II in FIG. 1 of the arrangement according to FIG. 1,

FIGS. 3, 4 and 5 are side views partly in section of details of three modified forms of embodiment of the radial drilling machine according to FIG. 1.

The radial drilling machine shown in FIG. 1 has a column 1 which is rotatably supported on the base frame 2 at 3 and 4, and which can be moved up and down, for example, by means of the threaded spindle 5 and the nut 6, for instance, with the help of the driving wheel 7. At the upper end the column is rigidly connected with the roller box 8, within which the cantilever arm 9 together with the boring head 10 is guided so as to be displaceable to and fro longitudinally according to the arrow 11, in a manner known per se. The cantilever arm 9 runs on three pairs of rollers 40a, 40b, 40c mounted on the roller box 8 and is fixed and clamped in its position conveniently by being pressed against a slide way connected with the roller box by an appropriate clamping mechanism 41. The column 1 can be moved up and down according to the arrow 12. It is rigidly connected with the base frame by means of the column clamping mechanism 42.

In order to ensure on the one hand that the column is guided securely and unrotatably during the vertical up and down displacement of the column according'to the arrow 12 and to make possible, if necessary, on the other hand, a rotational movement of the column about its longitudinal axis 13 according to arrow 14, a section of that part of the column which is within the base frame 2 has been embedded according to the invention at least along a part of the periphery of the column into a holding device 15 that is guided so as to be movable up and down by means of a shoulder gliding along a vertical guide 16, and that can be locked with the column so as to be unrotatable or can be unlocked from it so that the rotational motion of the column around its longitudinal axis 13 may be prevented or may be made possible. Hereby, the holding device can be rigidly connected with the column by means of a clamping connection which in its ineffective position allows a rotation of the column around its longitudinal axis with respect to the holding device. With the embodiment according to FIGS. 1 and 2 the holding device consists of a plate-like form piece 15 that conveniently extends in a plane rectangular to the longitudinal axis 13 of the column, and which surrounds at one end the column as shown at 17, whereas at the other end it slidingly engages on the vertical guide bar 16. This vertical guide bar may have a circular cross section and may be afiixed to the base frame. The respective connections, for instance five in our drawing, are represented at 18. The said guide bar is embraced by the bifurcated end of the holding device with two projections or

extensions

19 and 20. and this holding device can be fixed in any position desired without clearance by means of the regulating or adjusting screw 21. The holding device can also slidingly embrace the guide bar by means of a ball bearing like part. With another embodiment of the invention the guide bar has on the side facing the column a cross section like an U and the holding device is guided with a pivot on this U-like guide. The form piece 15 surrounds the column ring-like and has on one side a slot 22 extending radially with respect to the longitudinal axis 13 of the column, whereby the ends 22a, 22b of the ring surrounding and enclosing the column can be clamped against each other in the zone of the slot in order to get a clamping connection between the holding device and the column by means of at least one screw 23 or by means of springs, magnets, by means of a hydraulic arrangement, etc., whereby the clamping force acts in a direction tangential to the peirphery of the column. The breadth of the plate-like holding device 15 decreases from an amount that slightly surpasses the diameter of the column 1 to an amount that is a little greater than the diameter of the guide bar 16, whereby the border zones 24a, 24b extend obliquely with approximatively the same angle with respect to a vertical plane, and whereby the shoulders or extensions 22a, 2212 which are held together by the screw 23 extend radially with respect to the column. This plate-like form piece is conveniently arranged on the lower end of the column 1.

With the conventional radial drilling machines the motor 43 and the gear 44 are attached to the boring head as indicated by the dotted lines. It can be realized that in this case and in particular when the cantilever arm has been displaced in outward direction the pressure exerted on the side facing the boring head of the bearing 4 and on the side turned away from the boring head of the bearing 3 is especially great, whereby the friction is increased and the rotatory movement is impeded or detrimentally influenced. In such cases there are eventually expensive antifriction bearings necessary. The change of the position of the motor as well as of the gear as indicated at 45 and 46 results in a balance of weight and consequently in a reduction of the pressure on the bearing surfaces and, therefore, in facilitating the rotatory movement so that eventually antifriction bearings are no more necessary.

With the embodiment according to FIG. 3 the holding device is again plate-like shaped, whereby it surrounds the column 25 like a ring. This column has a single longitudinal slot 27 or several slots beginning at the lower end of the column and extending vertically upwards in the direction of the longitudinal axis 26 of the column. By means of this slot or these slots the circumference of the column can be expanded so that the column and the holding device are clamped with each other.

With the embodiment according to FIG. 4 an electromagnetic shaft coupling known per se serves for locking or clamping the holding device 47 With the column 48, whereby the part 38 of the coupling is rigidly connected with the column 48 and the coupling part 37 is rigidly connected with the holding device 47. By switching in or out the electric current the column can selectively be rigidly locked with the holding device or unlocked therefrom.

As can be seen the guiding elements for the column and the holding device are removably attached to the base frame respectively to the column. Therefore, the radial drilling machine can be delivered and used with and without the holding device and the guiding elements according to the necessities of the users, whereby the holding device representing a constructive group for itself can be mounted without difiiculties to the machine.

It is suitable to actuate the clamping connections between the column and the holding device represented in FIGS. 2 to 5 by some remote control whether mechanical or electro-motive 0r electro-magnetic or hydraulic or pneumatic.

The device operates in the following manner: Whenever it is desirable to maintain the position during the up and down movement of the column, the cantilever arm and the holding device are locked in their position, whereas the clamping mechanism 42 for the column is released during the up and down movement of the column. It is recommendable to use for that purpose one of the remote controls mentioned above. During the operation itself, for instance, when boring it is suitable and convenient to actuate and lock the clamping mechanism 42 for the column, too. All clamped connections are loosened, and" released, if the machine has to pass over from a certain working position to another one.

It is of advantage for certain Working operations to make the arrangement, for example, by a serial connection of electric relays such that with the actuation of the push button Up or Down of the remote control, the holding device is blocked first, in order to have, for the up and down movement, a column that cannot swing or rotate at all.

Although my invention has been illustrated and described with reference to the preferred embodiments thereof, 1 wish to have it understood that it is in no way limited to the details of such embodiments, but is capable of numerous modifications within the scope of the appended claims.

Having thus fully disclosed my invention, what I claim is:

1. A radial drilling machine comprising in combination: a base frame; a vertically extending column of circular cross-section mounted on said base-frame for rotational movement about its longitudinal axis and movable up and down in vertical direction; drive means carried by said base-frame and operatively engaging said column for imparting to said column vertical up and down movement; a roller box attached to the upper end of said column, said roller box containing several guide rollers; a cantilever arm arranged at the upper end of said column and extending transverse to the said column, guide rollers on said roller box guiding the said cantilever arm so as to be displaceable in longitudinal direction; a tool carrying boring head supported on the one end of said cantilever arm; the said column having a portion contained within the said base frame, a holding device enclosing the said portion at least along a part of the periphery of the said column, said holding device having an extension, a vertical guide on said base frame, said extension operatively engaging said vertical guide so as to be vertically movable up and down.

2. The radial drilling machine set forth in claim 1, wherein the said cantilever arm carries on its other end the driving motor and the gear connecting the said driving motor and the said boring head.

3. The radial drilling machine set forth in claim 1, wherein a clamping device is provided for connecting said holding device rigidly with the said column, said clamping device allowing in its inoperative position a rotation of the said column with respect to the said holding device about the longitudinal axis of the said column.

4. The radial drilling machine set forth in claim 1, wherein the said holding device comprises a plate-like piece extending at least principally in a plane which is perpendicular to the longitudinal axis of the column, said holding device embracing with its one end the said column and slidingly engaging with its other end the vertical guide.

5. The radial drilling machine set forth in claim 4, wherein the said vertical guide comprises a guide bar attached to the said base frame and engaged by a forklike end of the holding device, the said connection between the said fork-like end of the said holding device and the said guide bar being adjustable by means of a screw means extending radially to the axis of the said bar.

6. The radial drilling machine set forth in claim 5, column in order to establish a clamping connection wherein the plate-like piece constituting the said holdbetween the said holding device and the said column. ing device is arranged on the lower end of the said column.

7. The radial drilling machine set forth in claim 6, References Cited wherein the piece constituting the said holding device encloses the said column and has a through-slot extending radially to the longitudinal axis of the said column, where- FRANCIS S. HUSAR, Primary Examiner by the two ends of the ring enclosing the said column may be pressed against one another by means of a clamping force directed approximately tangentially to the said 10 1436 5 German Printed Application, 1,208,976, Jan. 13, 1966.