WO2008097084A1

WO2008097084A1 - Multi-spindle drilling machine

Info

Publication number: WO2008097084A1
Application number: PCT/NL2008/050063
Authority: WO
Inventors: Gerrit Cornelis Koese
Original assignee: Gerrit Cornelis Koese
Priority date: 2007-02-06
Filing date: 2008-02-05
Publication date: 2008-08-14
Also published as: EP2139632A1; NL1033347C2

Abstract

The invention relates to a multi-spindle drilling machine (1), comprising a plurality of drills (3) arranged in an initial pattern, which are each driven by a flexible spindle (5). The machine further comprises the same plurality of retraction mechanisms (10), which are designed for adjusting the drills (3) individually between an extended, operational position, wherein the respective drill (3) participates in the drilling process, and a retracted, passive position, wherein the respective drill (3) does not participate in the drilling process. The invention further relates to a coding system and coding method for coding workpieces with a unique pattern of holes with the aid of a drilling machine (1) according to the invention.

Description

P73971PC00

Title: Multi-spindle drilling machine

The invention relates to a multi-spindle drilling machine. Such a drilling machine is known from, for instance, EP 0 251 388 of applicant. With such a drilling machine, in one drilling pass, a number of holes can be drilled simultaneously. It is an object of the invention to provide an improved drilling machine of the type mentioned hereinabove in order to enlarge the possibilities of use of such a drilling machine.

To that end, a drilling machine according to the invention is characterized in that retraction mechanisms are provided with which each drill can be individually adjusted between an extended, operational position, wherein the respective drill participates in the drilling process, and a retracted, passive position, in which the respective drill does not participate in the drilling process.

Thus, a pattern of holes to be drilled with a drilling machine can be changed rapidly and simply. Rapidly, in that the individual drills can be adjusted simultaneously with the aid of the retraction mechanisms, and simply, in that the drills need not be loosened or slid in manually, one by one. As, furthermore, through suitable adjustment of the individual drills, a particularly large number of different patterns of holes can be effected, a drilling machine according to the invention is highly suitable for coding workpieces, for instance casts for the automobile industry. Here, each pattern of holes can serve as unique identification code on the basis of which, at all times, the workpieces can be identified and traced. Owing to the speed with which these patterns of holes can be adjusted and provided, this technique is also suitable for large series of workpieces, or mass production. In particular with such large numbers, but also with smaller series, it is preferred, when generating and adjusting the identification codes, or patterns of holes, respectively, to utilize a central control unit, such as a computer. With it, codes once provided can also be read out and stored, and a digital file can be linked to these codes in which file relevant information with respect to the workpiece can be stored.

In a further elaboration of the invention, the retraction mechanisms are substantially provided with respective spindles located on sides remote from the respective drills. As the retraction mechanisms are located at a distance from the respective drills, drills arranged in an initial pattern can be relatively closely spaced. This allows for drilling of a pattern of holes where the holes are relatively close together. It is possible, for instance, to arrange the different drills in a pattern such that the minimum distance between two neighbouring drills can be, approximately, 0.2 mm. In this manner, patterns of holes can be drilled where for instance all holes, for instance 30 - 40 holes, are within a square centimetre.

In the further subclaims, further advantageous embodiments of a drilling machine and a method according to the invention are described. In clarification of the invention, exemplary embodiments of a drilling machine according to the invention and the use thereof will be explained in further detail on the basis of the drawing. In the drawing:

Fig. 1 shows a multi-spindle drilling machine according to the invention;

Fig. 2 shows an embodiment of a retraction mechanism according to the invention for use in a drilling machine as shown in, for instance, Fig. 1;

Fig. 3 shows an alternative embodiment of a retraction mechanism according to the invention; Fig. 4 shows a multi-spindle drilling machine with an alternative retraction mechanism according to the invention; and

Fig. 5 shows, in further detail, the retraction mechanism of Fig. 4.

Fig. 1 schematically shows a first exemplary embodiment of a multi- spindle drilling machine 1 according to the invention, driven by a hand drilling machine 2. For a detailed description of such a drilling machine 1 and the operation thereof, reference is made to the above-mentioned patent EP 0 251 388 of applicant, the content of which is understood to be incorporated herein by reference. In the following, a summary description of the drilling machine 1 will suffice, insofar as necessary for a good understanding of the invention.

The drilling machine 1 comprises a number of drills 3 which are included in a drill guide block 4 in a particular, desired initial pattern. The initial (or mother) pattern may be a grid of rows and columns, for instance seven by seven, or a pattern of concentric circles. Naturally, other numbers and pattern configurations are possible.

Each drill 3 is driven by a spindle 5 of at least partly flexible design, which is bearing mounted in a housing 6 of the drilling machine 1 for rotation about a central drive wheel 8 which, in use, drives the spindles 5. To that end, the spindles 5 are each provided with a pinion 7 or friction wheel (as described in the earlier mentioned patent) engaging this drive wheel 8. In turn, the central drive wheel 8 is driven by external drive means, such as the already mentioned hand drilling machine 2 or the vertical drill column shown in Fig. 4.

Each spindle 5 may be designed to be solid or hollow and preferably has a relatively small thickness, for instance in the order of 1 mm. As a result, the drills 3 and the holes to be drilled therewith can be closely spaced, having a minimum interspace of, for instance, approximately 0.2 mm, and the total pattern of holes can have limited dimensions, for instance 30-40 holes per square centimetre. Furthermore, as a result, the spindles 5 are sufficiently flexible for assuming the curved position shown in Fig. 1. Preferably, the spindles 5 are connected to the drills 3 via detachable couplings 9 (shown only schematically) so that the drills .3 can be easily replaced. The drill guide block 4 and optional further guide provisions for the spindles too are preferably detachable so that, if desired, they can be easily replaced, for instance by blocks 4 with a different initial pattern. An advantage of the construction of the drill guide block with accurately positioned drills therein is that the drills can be driven at very high speed, which is favourable for the drilling time. With drills with a diameter of 4mm, a speed of, for instance, 30,000 rpm can be reached.

The drilling machine 1 can further comprise a depth stop 11, a handle 12 for ease of use and/or attachment means 13 for a balancing mechanism (not shown). Each spindle-drill combination 3 — 5 is further provided with a retraction mechanism 10 according to the invention, with which the drills 3 can be adjusted between an operational, extended position, wherein the respective drill 3 participates in the drilling of a pattern of holes, and a retracted position, wherein the drill 3 does not participate and hence will not form a hole during drilling. Preferably, the retraction mechanisms 10 are substantially provided on sides of the spindles 5 remote from the respective drills 3. On that side of the spindles 5, there is sufficient space for providing the retraction mechanisms 10 and the central drive wheel 8, even when the drilling machine 1 comprises a very large number of drills 3 to be driven. A drill 3 to be retracted is retracted by the respective retraction mechanism 10 in that the retraction mechanism 10 retracts the spindle 4 provided on the drill 3 to be retracted. The central drive wheel 8 drives the spindles 5 substantially on an end remote from the drills 3. The retraction mechanisms 10 can be designed in different manners. In the following, a number of exemplary embodiments will be described.

Fig. 2 for instance shows an embodiment wherein, with the aid of biasing means 14, in particular draw springs, a spindle-drill combination 3-5 is held in retracted position. The spindle 5 and drill (not visible in Fig. 2) can be moved to an extended position, with the aid of a piston-cylinder assembly 15, against the biasing force of the biasing means 14. The piston-cylinder assembly 15 is arranged in line with the spindle 5, in a bore 16 in the housing 6 of the drilling machine 1, and the spindle 5 is connected to the piston 15, via an axial bearing 18. As a result, the spindle 5 will be carried along in axial direction (i.e. in the direction of the longitudinal axis of the spindle) by the piston 15, but will be able to rotate freely about this longitudinal axis. As a result, the spindle 5 can be driven undisturbedly by the earlier mentioned drive wheel 8 and pinion 7 or friction wheel, both in the retracted position and in the extended position. The associated drill 3 is therefore also driven in the retracted position. Naturally, embodiments are possible in which the drill 3 is not driven in retracted position, for instance in that, in such a position, the earlier mentioned pinion 7 or friction wheel does not engage the drive wheel 8. The piston-cylinder assembly 15 may be driven pneumatically or hydraulically, via pneumatic or hydraulic circuits provided to that end.

Fig. 3 shows an alternative embodiment of a retraction mechanism 110 according to the invention, wherein a screw spindle 117 is utilized, which can be driven by, for instance, an electric motor 119 and optional suitable delay means 120. About the spindle 117, a worm nut 115 is provided which, depending on the direction of rotation of this spindle 117, moves upwards or downwards along the spindle 117as far as stops 121, 122 provided to that end. The worm nut 115 is connected to a spindle 105 by means of a bearing 118. Like the above mentioned axial bearing in Fig. 2, this bearing 118 ensures that the spindle 105 is carried along by the worm nut 115 when this latter moves along the spindle 117, and further ensures that the spindle 105 can rotate freely relative to the worm nut 115. As shown in Fig. 3, the spindle 105 is provided at a distance of the worm nut 115 with a pinion 107 or friction wheel which, in use, both in the retracted and in the extended position, engages the drive wheel (shown in Fig. 1). Naturally, the position of the pinion 107 or friction wheel can be adjusted such that it is in engagement with the drive wheel only when the drill is in extended position.

The retraction mechanism 110 can further comprise biasing means 114, such as, for instance, a spiral spring as shown. With it, any clearance between the worm nut 115 and the screw spindle 117 can be pressed away in order to prevent slip. In addition, these biasing means 114 can, again, be arranged for biasing the spindle-drill mechanism in the retracted position. Then, the spindle 117, motor 119, 120 and worm nut 115 serve only for moving the drill from this retracted position to the extended, operational position, against the biasing force. Fig. 4 shows a further embodiment of a multi-spindle drilling machine 101 according to the invention. The drilling machine 101 substantially corresponds to the embodiment shown in Fig. 1, but is included in a vertical drilling set-up. In this case, the drive wheel 108 of the drilling machine 101 is driven via an axis mounted vertically next to the drilling machine 101, and a suitable belt transmission 102. The drilling machine 1 is further provided with alternative retraction mechanisms 210, of which two are shown in Fig. 4, one in retracted position (on the left hand side) and one in extended position (on the right hand side). The mechanism 210 in retracted position is shown in further detail in Fig.5 and will be described further in the following.

With this alternative retraction mechanism 210, as in the embodiment according to Fig. 2, use is made of a pneumatically or hydraulically operable piston 215 for moving the spindle 205 and drill (not shown) from a retracted position to an extended position and/or vice versa. Here, in the exemplary embodiment shown, the piston 215 is arranged next to the spindle end 205 instead of in line therewith, and connected via a lever 224 to this spindle end 205 (at least via a number of intermediate elements, among which an axial bearing 218). Owing to the lever 224, the effective force on the spindle end 205 can be increased in order to thus provide sufficient counterforce to forces occurring during drilling. Like in the earlier described embodiments, the spindle 205 is, once more, connected (via bearing 218) to the piston for rotation and preferably driven during both the extended position and the retracted position (in that, in both positions, the pinion 207 or friction wheel remains in engagement with the drive wheel 208, as shown). Furthermore, again, biasing means may be provided for biasing the spindle with drill in one of the two positions, preferably the retracted position.

A drilling machine 1, 101 as described hereinabove can be advantageously used for coding workpieces with a unique identification code. To that end, the identification codes are translated into a desired unique pattern of holes, starting from the available initial pattern of the drills 3 (and drill guide block 4). Prior to drilling a code, the drills are positioned with the aid of the above described retraction mechanisms 10, 110, 210, into the correct position, Le. extended or retracted. Owing to these retraction mechanisms 10, 110, 210, this can be done very rapidly. After that, the entire drilling machine 1, 101 is brought into position and the set pattern of holes is drilled into the workpiece in one drilling pass. As all holes are drilled simultaneously, the time of application is short. This can be, for instance, in the order of 2 seconds. As a result, this technique is highly suitable for coding large series of workpieces.

According to an advantageous embodiment, the drills 3 can be detachably connected to the drive spindles 5, 105, 205, so that the drills can be easily replaced, for instance in case of wear or when holes of other dimensions are desired. For this connection, couplings can for instance be used as described in the Dutch patent application entitled "Coupling for connecting two elements in a manner restrained from rotation in one direction of rotation, and drilling machine equipped therewith", filed on the same day as the present application, by the same applicant. With these couplings, it is possible to position the drills 3 closely together, so that the total dimensions of the pattern of holes to be drilled can be reduced. Furthermore, these couplings can be detached simply and rapidly, without great loosening moments and/or special tools being required thereto.

According to a further advantageous aspect of the invention, the drilling machine 1 is preferably coupled to a central control unit (not shown) such as a computer. This computer can generate the desired identification codes / patterns of holes (by translating decimal serial numbers into a binary code) and, on the basis thereof, drive the retraction mechanisms 10, 110, 210. The provided codes or patterns of holes, respectively, are stored directly after drilling. Then, to this stored code, a data sheet can be linked, in which relevant information with respect to the workpiece with this code can be stored. The invention is not limited in any manner to the exemplary embodiments represented in the description and the drawing. All combinations of (parts of) embodiments described and/or shown are understood to fall within the inventive concept. Furthermore, many variations thereon are possible that are within the framework of the invention as set forth in the following claims.

Claims

1. A multi-spindle drilling machine, comprising a plurality of drills, arranged in an initial pattern, which are each driven by a flexible spindle, and the same plurality of retraction mechanisms, which are designed for adjusting the drills individually between an extended, operational position, wherein the respective drill will participate in the drilling process, and a retracted, passive position, wherein the respective drill will not participate in the drilling process.

2. A drilling machine according to claim 1, wherein the retraction mechanisms are provided substantially on sides of the respective spindles remote from the respective drills.

3. A drilling machine according to claim 1 or 2, wherein the respective spindles are connected to the retraction mechanisms such that they move along with the retraction mechanisms in a direction parallel to their longitudinal axis, and are freely rotatable about said longitudinal axis relative to the retraction mechanism.

4. A drilling machine according to claim 3, wherein the respective retraction mechanisms are designed for retracting the respective drills by retracting the respective spindles provided between the drills and the retraction mechanisms.

5. A drilling machine according to any one of the preceding claims, wherein the spindles are driven by a central drive element, both in the extended, operational position and in the retracted, passive position.

6. A drilling machine according to claim 5, wherein the central drive element is designed for driving the spindles substantially on an end remote from the drills.

7. A drilling machine according to any one of the preceding claims, wherein the retraction mechanisms comprise pneumatic, hydraulic, electric and/or piezo-electric drive means.

8. A drilling machine according to any one of the preceding claims, wherein the initial pattern in which the drills are arranged is a grid of rows and columns.

9. A coding system for coding workpieces with a unique pattern of holes, comprising a drilling machine according to any one of the preceding claims and a central control unit for translating identification codes into a unique pattern of holes, and for driving, on the basis thereof, the retracting mechanisms so that a pattern of holes to be drilled with the drilling machine corresponds to the desired unique pattern of holes.

10. A coding system according to claim 9, wherein the central control unit is further designed for coupling to each newly generated identification code or pattern of holes, respectively, a file for storing data relevant to the workpiece provided with the respective identification code or pattern of holes, respectively.

11. A method for coding workpieces, for instance casts for the automobile industry, with a unique pattern of holes, comprising the following steps: generating a unique identification code; converting this unique identification code into a unique pattern of holes, starting from the initial pattern of holes of a drilling machine according to any one of claims 1 - 8; - driving the retraction mechanisms of a drilling machine according to any one of claims 1 — 8, for realizing the pattern of holes determined in the previous step; drilling a pattern of holes in a workpiece with the aid of the drilling machine set in the previous step; repeating the previous steps, wherein for each new workpiece a new, unique identification code and associated pattern of holes is generated and realized, respectively.

12. A method according to claim 11, wherein the provided pattern of holes is read and is coupled to a file in which further data relating to the associated workpieces are stored, such as data about the conditions of manufacture, date, manufacturer, residence, etc.