US3232364A

US3232364A - Drilling apparatus

Info

Publication number: US3232364A
Application number: US271774A
Authority: US
Inventors: Fischer Artur
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-04-16
Filing date: 1963-04-09
Publication date: 1966-02-01
Anticipated expiration: 1983-02-01
Also published as: AT254490B; DE1184062B

Description

Feb. 1, 1966 A. FISCHER DRILLING APPARATUS 3 Sheets-Sheet 1 Filed April 9, 1963 INVENTOR.

ARTUR FISCHER BY MICHAEL S. S'TR/KER ATTOR 3 Sheets-Sheet 2 Filed April 9,

Fig.9

Fig.70

INVENTOR.

ARTUR FISCHER BY MICHAEL S SYRIKER IQTTORNEY Feb. I, 1966 A. FISCHER 3,232,364

DRILLING APPARATUS Filed April 9, 1963 3 Sheets-Sheet 5 IIIJI/ INVENTOR.

ARI'UR FISCHER BY lVl/CHAEL S. STRIKER #TTORNE) Patented Feb. 1, 1966 8 Claims. (Cl. 175-403 The present invention relates to drilling apparatus in general and, more particularly, to an improved drilling apparatus which is especially suited for making expansion-anchor holes in masonry, such as concrete, brick, stone, rock, plaster, mortar and similar building materials of brittle consistency. Such holes are often drilled to accommodate slotted parts of anchoring bolts which are thereupon caused to expand and to engage with great force the material of a wall construction or the like. The tools of drilling apparatus which are used for making holes in granite, concrete or the like must be mounted in such a way that they are held against rotation and against axial movements with respect to their supports. Furthermore, since the tools are subjected to considerable wear and tear, they must be mounted in a manner to permit rapid exchange without, however, aifecting the strength of the connection between the tool and its support when the apparatus is in actual use.

Accordingly, it is an important object of the present invention to provide a very simple but highly reliable connection between a drilling tool and its support and to construct such parts in a way to permit exceptionally simple and very rapid removal or reinsertion of the tool.

Another object of the invention is to provide a supporting member for drilling tools which is provided with novel means for normally preventing withdrawal of a tool and which may be coupled with the drive of a power drill or with a hand-operated drilling apparatus to transmit rotary motion to the tool. A further object of the invention is to provide a drilling apparatus for making holes in concrete or the like which may be manufactured at low cost and which may be coupled with solid rod-like tools or with specially configurated tubular drilling tools.

An additional object of the invention is to provide a novel connection between a drilling tool and its supporting member which is constructed and assembled in such a way that the tool is automatically locked to the supporting member when the drilling apparatus is in actual use.

A concomitant object of the invention is to provide a connection which forms an integral part of the tool and/ or of the supporting member.

With the above objects in view, one feature of the invention resides in the provision of a drilling apparatus, particularly for making expansion-anchor holes in granite, concrete, brick, plaster and the like. This apparatus comprises a rotary supporting member which may assume the form of an attachment adapted to be inserted into the chuck of a power drill and which comprises an end portion provided with an inwardly extending axial opening or bore, an elongated cutting tool having a toothed or conical cutting element at one end and a motion transmitting portion at the other end thereof, and means including a slot or groove provided in one of these portions and a projection provided on the other portion and slidably extending into the slot for drivingly coupling the supporting member with the tool. The projection and the slot may constitute a bayonet lock or, alternatively, the drilling apparatus may comprise special retaining means carried by the supporting member and engaging with the tool for normally preventing withdrawal of the motion transmitting portion from the opening in the end portion of the supporting member.

The tool may assume the form of a tubular body formed with a projection which extends tangentially from the motion transmitting portion or, alternatively, the tool may be a solid profiled rod with a substantially radial projection which is obtained by deforming the motion transmitting portion so that the cross section of that part of the motion transmitting portion which is adjacent to the projection is of smaller area than the cross section of the remainder of the tool.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved drilling apparatus itself, however, both as to its construction and the method of assembling its parts, together with additional features and advantages thereof, will be best understood from the following detailed description of certain specific embodiments with reference to the accompanying drawings, in which:

FIG. 1 is an exploded perspective view of a portion of a drilling apparatus which embodies one form of my invention;

FIG. 2 is a fragmentary partly elevational and partly sectional view of the parts which are shown in FIG. 1 and which are illustrated in partly assembled position;

FIG. 3 is a transverse section as seen in the direction of arrows from the line III-III of FIG. 2;

FIG. 4 is a fragmentary partly elevational and partly sectional view of the parts shown in FIG. 2 which are illustrated in fully assembled position;

FIG. 5 is a fragmentary partly elevational and partly sectional view of a modified drilling apparatus whose parts are shown in fully assembled position;

FIG. 6 is a transverse section as seen in the direction of arrows from the line VI-VI of FIG. 5;

FIG. 6a is a transverse section through a drilling apparatus which is very similar to the apparatus of FIGS. 5 and 6 but whose tool is retained in its supporting member in a slightly different way;

FIG. 7 is a fragmentary partly elevational and partly sectional view of an additional drilling apparatus wherein the tool is detachably secured to its supporting member by means of a threaded member;

FIG. 8 is a transverse section as seen in the direction of arrows from the line VIII-VIII of FIG. 7;

FIG. 9 is a side elevational view of a tool which may be used in certain of the drilling apparatus shown in FIGS. 1 to 8;

FIG. 10 is a transverse section as seen in the direction of arrows from the line X-X of FIG. 9, further showing a portion of a supporting member which may be used to receive and to rotate the tool of FIG. 9;

FIG. 11 is a fragmentary exploded view of a drilling apparatus wherein the supporting member and the drilling tool may be coupled by means of a bayonet lock which includes an L-shaped groove or slot provided in the periphery of the tool and a cooperating projection provided on the supporting member;

FIG. 12 is an end view of the supporting member as seen in the direction of arrows from the line XIIXII of FIG. 11;

FIG. 13 illustrates the parts of FIG. 11 in partly assembled position;

FIG. 14 is a transverse section as seen in the direction of arrows from the line XIVXIV of FIG. 13;

FIG. 15 shows the structure of FIGS. 11 and 13 in fully assembled position;

FIG. 16 illustrates the structure of FIG. 15 in a different angular position and in partial axial section taken along the line XVIXVI of FIG. 15; and

FIG. 17 is a fragmentary exploded view of a different drilling apparatus wherein the drilling tool is provided with a projection receivable in an L-shaped groove of the supporting member.

Referring now in greater detail to the drawings, and first to FIGS. 1 to 4, there is shown a portion of a drilling apparatus which is particularly suited for making expansion-anchor holes in concrete, plaster, brick and similar brittle building materials. Such holes are used to receive certain parts of anchor bolts, and the parts received in the holes are thereupon caused to expand so as to retain the bolts with great force even if the nature of the surrounding material is such that it is normally incapable of providing a strong support for a threaded bolt or a similar device.

The drilling apparatus comprises a rotary supporting member 1 which is normally of cylindrical shape and whose front end portion 11) is formed with an axial opening or bore 3 which extends inwardly from its end face 10 and which communicates with a laterally extending groove or slot 4. This slot may but need not extend all the way to the periphery of the end portion 1b and is substantially tangential to the bore 3, see particularly FIG. 3.

The end portion 1b carries a retaining device which assumes the form of a cap having an annular flange 5a and an inwardly extending annular collar 5b which is rigid with the flange 5a and which overlies and is adjacent to the end face 10. The collar 517 has a central opening 50 which communicates with an outwardly extending tangential recess 7, and this recess may be moved into registry with the front end of the slot 4 in response to rotation of the cap 5 about the end portion 1b of the supporting member. As shown in FIGS. 2 and 4, the end portion 112 is formed with a circumferential groove 1:: which receives an inwardly extending annular bead 6 at the rear end of the flange 5a so that the cap 6 is free rotate about but is held against axial movements with respect to the supporting member. If desired, the bead 6 may be fitted in its groove la with at least some friction so that the cap 5 is not likely to rotate with respect to the supporting member unless it is grasped by fingers or by a suitable tool.

The end portion 112 further comprises an internal shoulder 3a which extends into the bore 3 at a given distance from the end face 1c and which serves as an abutment or stop for the motion transmitting portion 2c at the rear end of a specially configurated drilling tool 2 best shown in FIG. 1. The tool comprises at its front end a cutting element 2a of toothed profile. The exact construction of this tool forms no part of my invention and the method of making it will be described solely for the purpose of completing the disclosure. In making the tool, one starts with an L-shaped blank or plate of tool steel which is thereupon rolled or convoluted about an axis parallel with one of its legs so as to form a tubular body and that the other leg extends tangentially from the tubular body. This laterally or tangentially extending non-convoluted leg then forms a fiat projection or lug 2d which serves to hold the tool 2 against rotation with respect to the supporting member 1 when the motion transmitting portion 20 of the tool is inserted into the bore 3. The projection 2d then fits into the slot 4 and cooperates with the walls bounding this slot to prevent angular displacements of the portion 2c with respect to the end portion 111. The rear end face 2c of the motion transmitting portion 2c abuts against the shoulder 3a and the axial length of the projection 2d is normally selected in such a way that its front end face is very near to or actually abuts against the inner side of the collar 5b when the end face 2e abuts against the shoulder 3a. This insures that the tool 2 is held against axial rovements with respect to the supporting member 1 (see FIG. 4) excepting, of course, at such times when an operator intentionally turns the cap 5 to a position in which the recess 7 registers with the slot 4 (FIG. 2) so that the motion transmitting portion 20 may be withdrawn from the end portion 112.

The teeth of the cutting element 2:: are preferably formed before the blank is convoluted to assume the shape of a tubular body. As a rule, the blank may be stamped from a larger sheet of tool steel or similar wearresistant material. The slot 2b which is best shown in FIG. 1 lends some elasticity to the tool and provides a path for the escape of concrete, brick, mortar or like material when the drilling apparatus is put to actual use. The projection 2d may form part of a comparatively long arm which is shortened by cutting, filing or in any other suitable way after the blank is convoluted into a slotted body of tubular shape.

The rear end portion 10 of the supporting member preferably assumes the form of a wedge which may be inserted into the drill chuck of a power drill or into the chuck of a manually driven drilling or boring apparatus. Of course, the supporting member may be coupled directly to the output shaft of an electric motor or to the output shaft or" a transmission which is driven by the motor of a drilling apparatus.

FIGS. 5 and 6 illustrate a portion of a slightly different drilling apparatus whose supporting member 11 is very similar to the supporting member 1 excepting that its end portion 11b need not be provided with a circumferential groove because the projection 12d which forms part of the motion transmitting portion 120 of a tubular tool 12 is releasably retained in the bore 13 in a slightly different way. This projection 12d again fits into a laterally extending slot 14 which is substantially tangential to the bore 13, and its front end face 12f (i.e., that end face which is turned toward the non-illustrated cutting element of the tool 12) is spaced inwardly from the end face of the portion 11b so that it may be engaged by a pin 18 which is fitted into a transversely extending eccentric bore 11) of the end portion 11b. In the embodiment of FIGS. 5 and 6, the pin 18 is nearly entirely concealed in the bore 11] and is held merely by friction so that it cannot be ejected by centrifugal force when the supporting member 11 is caused to rotate. The rear end face 12a of the motion transmitting portion 12 abuts against an internal shoulder 13a of the end portion 11b so that the shoulder 13a and the pin 18 cooperate to hold the tool 12 against axial movements with respect to the supporting member. Angular movements of the tool are prevented by the projection 12d which has a sliding fit in the slot 14 and which may be withdrawn from this slot as soon as the pin 18 is removed.

FIG. 6a illustrates a slightly different arrangement wherein the projection 22d of a tubular tool 22 is formed with a bore 22g which is in registry with the transverse bore 21 of the end portion 21b. The pin 18 is replaced by a threaded bolt 28 whose head 28a may be engaged by fingers and whose threaded terminal portion may be screwed into the threaded portion of the bore 21]. An important advantage of the arrangement shown in FIG. 6a is that the cutting tool 22 may be exchanged with little loss in time and that no special tools are necessary for such operation.

FIGS. 7 and 8 illustrate a supporting member 31 which is similar to the supporting member 11 and which serves to transmit rotation to and to support a slightly different tubular tool 32 having comparatively short projection 32d which extends tangentially from the motion transmitting portion 320, the latter being slidably received in the axial bore 33 of the end portion 31b of the supporting member and abutting against a shoulder 33a. The retaining means for the motion transmitting portion 320 comprises a comparatively short threaded member, such as a conventional screw 39 with aslotted head, and thisscrew is driven into a radial bore 31 of the end portion 31b so as to bear with its tip directly against the portion 320 of the tool. This portion 320 is resilient because the tool 32 is slotted so that the screw 39 will safely hold the tool against any axial movements. As shown in FIG. 7, the projection 32d extends all the Way to the periphery of the supporting member 31 to fill the respective section of the slot 34, and the arrangement is preferably such that the end portion 31b is formed with a depression which receives the head of the screw 39 so that this head stands in the way of the projection 32d and prevents axial movements of the tool even if the tip of the screw does not engage the motion transmitting portion 32:. Tthe head of the screw 39 thus cooperates with the internal shoulder 33a of the supporting member 31.

It will be readily understood that the screw 39 may be arranged in such a way that its head engages only against the front end face of the projection 32d or that its tip engages only the projection rather than the tubular portion 32c. For example, and referring to FIG. 8, the screw may be substantially perpendicular to and may bear with its tip against the underside of the projection 32d so that the arrangement would then resemble the one which is shown in FIG. 6a excepting that the screw would not extend through the projection.

, It is to be mentioned here that the

tubular tool

2, 12, 22 or 32 may be held against rotation even if that portion which fits into the respective supporting member is without a projection. All that is necessary is to provide a projection on the supporting member and to insert the tool in such a way that the projection fits into the longitudinal slot of the tool. Thus, and referring for example to FIG. 7, the supporting member 31 may be provided with a radially inwardly extending lateral lug which projects into the bore 33 and which may be received in the longitudinal slot of the tool 32 which latter is then without the projection 32d. This modification is so obvious that it can be readily comprehended without a separate illustration.

FIG. 9 illustrates a somewhat different drilling or cuting tool 42 which assumes the form of a solid rod and which is. preferably profiled in a manner best shown in FIG. 10. The tool comprises a conical cutting element 42a at One end and a motion transmitting portion 42c at the other end thereof, and this motion transmitting portion 42c comprises a substantially radially extending projection 42d which assumes the form of a flat lug and which may be fitted into a radial slot 44 provided in the end portion 41b of a rotary supporting member 41 shown in FIG. 10. The end portion 41b has an axial bore 43 which receives the motion transmitting portion 420. The projection 42d is formed by an upsetting or pinching machine as is evidenced by the small depressions 42/1 at both sides of this projection, i.e., the cross section of that part of the motion transmitting portion 421: which extends along the projection 4241 is smaller than the cross section of the remainder of the tool. By making the projection 42d in the just described manner, one can produce the tool 42 by cutting a predetermined length from an elongated bar or rod of tool steel, by sharpening one end of the thus obtained blank to form the conical cutting element 42a, and by thereupon upsetting or pinching the motion transmitting portion 42c to form the projection 42d.

The tool 42 may be held in the supporting member 41 by a cap such as the cap of FIGS. 14 or in a manner as shown in FIGS. 5-6 or 7-8. This too] is provided with a series of axially parallel reinforcing ribs and is releasably held in the supporting member by a pin 43. Drilling apparatus with tools of the type shown in FIGS. 9 and 10 are used for making holes in granite or in other hard building materials which are likely to deform or to break a thin-walled tubular tool.

FIG. 11 illustrates a portion of a drilling apparatus wherein an elongated tubular drilling tool 52 is coupled to a supporting member (see also FIG. 12) by means of a bayonet lock including an L-shaped groove or slot 54 provided in the periphery of the motion transmitting portion 520, and an internal projection 52d extetnding into the axial bore 53 of the end portion 51b. The motion transmitting portion 52c of the tool 52 is receivable in the bore 53 when the projection 52d is in registry with the open end of the axially parallel section 54a of the slot 54. The other end of this section 54a communicates with a second section 54b which extends circumferentially of the motion transmitting portion 520 and which resembles a portion of a helix. When the projection 52d slides in the section 54b in a direction away from the sec tion 54a (i.e., when the tool 52 is rotated in an anticlockwise direction, as viewed in FIG. 13), the end face 52c of the motion transmitting portion 52c comes into abutment with the bottom wall 53a of the bore 53 and cooperates with the projection to hold the tool against axial and angular movements (in one direction) with respect to the supporting member or vice versa.

FIGS. 13 and 14 illustrate the tool 52 and the supporting member 51 in partly assembled position. The projection 52d is located at the inner end of the section 54 and the tool is ready to be rotated in an anticlockwise direction, as viewed in FIG. 14, so that it will be wedged in the end portion 51b as soon as the end face 52e comes into abutment with the bottom wall of the bore 53. Such position of the

parts

51, 52 is shown in FIGS. 15 and 16.

In order to detach the tool 52, the operator merely rotates the supporting member 51 in a clockwise direction, as viewed in FIG. 15 or 16, and thereupon withdraws the tool from the bore 53. It willbe understood that, when the drilling apparatus is in actual use, the supporting member 51 is driven in a counterclockwise direction, as viewed in FIG. 15; otherwise, the projection 52d would return into the section 54a as soon as the non-illustrated cutting element of the tool 52 would abut against a solid body, such as a wall made of brick, concrete or the like. In other words, when the drilling apparatus is in actual use, the supporting member 51 must be rotated in a sense to move the projection 52d toward the closed end of the helical slot section 5411. The pitch of the section 54b is such that the projection 52d may enter this section but that the end face 52e is compelled to engage the bottomwall 53a at the time when or before the projection reaches the closed end of the section 54b.

, FIG. 17 illustrates a slightly modified drilling apparatus wherein the projection 62d is provided on the periphery, of the motion transmitting portion 62c forming part of a tubular drilling tool 62. This projection 62d formspart. of a bayonet lock and may be received in an L-shaped groove or slot 64 which is provided in the internal surface of the end portion 61b forming part of a rotary supporting member 61. The slot 64 has an axially parallel section 64a whose open outer end is located at theend face of the end portion 61b, and a helical section-64b which communicates with the inner end of the section 64a and which is inclined in such a way that the end face 622 of the motion transmitting portion 620 is compelled to abut against the bottom wall 63a of the axial bore 63 before or at the time the projection 62d reaches the closed end of the section 64b.

The

tool

52 or 62 may be manufactured at low cost by stamping a rectangular blank from a sheet of tool steel and by thereupon rolling the blank into the form of a tube. The projection 62d may be welded onto or otherwise secured to the motion transmitting portion 62c. In its preferred form, the

projection

52d or 62d assumes the shape of a hemispherical body. It goes without saying that the bayonet lock of FIGS. 11-16 or FIG. 17 may be used in connection with solid rod-shaped drilling tools of the type shown in FIGS. 9 and 10, and that it is not always necessary to form the

slot

54 or 64 with a helical section.

The main difference between the drilling apparatus of FIGS. 1 to 10 and the drilling apparatus of FIGS. 11 to 17 is that the bayonet lock serves as a means for holding the drilling tool against axial and angular movements with respect to the supporting member. On the other hand, the arrangement of FIGS. 1-10 is capable of holding the tool against angular movements in a clockwise or anticlockwise direction. Thus, when the tool and its supporting member are coupled by means of a bayonet lock, care must be taken to rotate the supporting member in a direction which will cause the

projection

52d or 62d to move toward the closed end of the helical slot section. Such precaution is not necessary when the connection between the tool and its supporting member comprises a retaining means such as the cap 5 or the pin 18.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic and specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a drilling apparatus, particularly for making holes in concrete and the like, in combination, a rotary supporting member comprising an end portion provided with an inwardly extending axial bore and with a slot extending substantially tangentially from and communicating with said bore; an elongated cutting tool of tubular shape, said tool having an annular cutting element at one end and an annular motion transmitting portion at the other end thereof, said motion transmitting portion being slidably received in said bore and comprising a substantially tangential flat lateral projection slidably received in said slot to hold said tool against rotation with respect to said supporting member; and retaining means detachably carried by said supporting member and releasably engaging said motion transmitting portion for normally preventing withdrawal of said tool from said end portion.

2. In a drilling apparatus, particularly for making holes in concrete and the like, in combination, a rotary supporting member comprising an end portion having an end face and provided with an axial bore extending inwardly from said end face, said end portion further having a slot extending laterally from and communicating with said bore and terminating at said end face; an elongated substantially tubular cutting tool having an integral annular cutting element at one end and a motion transmitting portion at the other end thereof, said motion transmitting portion being, received in said bore and having a substantially fiat elongated projection which is parallel with the longitudinal extension of said tool and is slidably received in said slot so as to hold the tool against rotation with respect to said supporting member; and retaining means for normally preventing withdrawal of said motion transmitting portion from said end portion, said retaining means comprising a cap having a rotatable annular flange permanently secured to said end portion and a collar rigid with said flange and adjacent to said end face, said collar having a central opening through which said tool extends and a recess extending outwardly from said opening, said recess being movable into registry with said slot in response to rotation of said flange to permit insertion or withdrawal of said motion transmitting portion from the end portion of said supporting member.

3. In a drilling apparatus, particularly for making holes in concrete and the like, in combination, a rotary supporting member comprising an end portion provided with an inwardly extending axial bore and having a slot extending substantially tangentially from and communicating with said bore; an elongated cutting tool having a rotary cutting element at one end and a cylindrically shaped motion transmitting portion at the other end thereof, said motion transmitting portion being slidably received in said bore and having a tangential lateral projection slidably received in said slot so as to hold the tool against rotation with respect to said supporting member; and retaining means releasably engaging said motion transmitting portion for normally preventing withdrawal of said motion transmitting portion from said end portion.

4. A combination as set forth in claim 3, wherein said retaining means comprises a pin received in a transverse bore provided in said end portion and engaging said motion transmitting portion.

5. A combination as set forth in claim 4 wherein said projection has a face which is turned toward said cutting element and wherein said pin engages said face.

6. A combination as set forth in claim 4 wherein said projection has a bore which is in registry with said transverse bore and which receives a portion of said pin.

7. A combination as set forth in claim 3 wherein said retaining means comprises a threaded member screwed into said end portion and engaging said motion transmitting portion.

8. A combination as set forth in claim 7, wherein said threaded member engages the projection of said motion transmitting portion.

References Cited by the Examiner UNITED STATES PATENTS 348,815 9/1886 Bailey 27991 598,173 2/1898 Brendner 279--9 1,149,398 8/1915 Nitteberg 2799 1,465,008 8/1923 Stephens 2799 X 1,471,714 10/1923 Veith 27989 X CHARLES F. OCONNELL, Primary Examiner.

BENJAMIN HERSH, Examiner.

Claims

1. IN A DRILLING APPARATUS, PARTICULARLY FOR MAKING HOLES IN CONCRETE AND THE LIKE, IN COMBINATION, A ROTARY SUPPORTING MEMBER COMPRISING AN END PORTION PROVIDED WITH AN INWARDLY EXTENDING AXIAL BORE AND WITH A SLOT EXTENDING SUBSTANTIALLY TANGENTIALLY FROM AND COMMUNICATING WITH SAID BORE; AN ELONGATED CUTTING TOOL OF TUBULAR SHAPE, SAID TOOL HAVING AN ANNULAR CUTTING ELEMENT AT ONE END AND AN ANNULAR MOTOR TRANSMITTING PORTION AT THE OTHER END THEREOF, SAID MOTION TRANSMITTING PORTION BEING SLID-