WO2019008132A1

WO2019008132A1 - A machining arrangement and a method for attachment to and machining a working piece

Info

Publication number: WO2019008132A1
Application number: PCT/EP2018/068351
Authority: WO
Inventors: Rune GJERVOLDSTAD
Original assignee: Gjervoldstad Rune
Priority date: 2017-07-07
Filing date: 2018-07-06
Publication date: 2019-01-10
Also published as: NO20171129A1

Abstract

The invention relates to a machining arrangement (1) and a method for attaching such an arrangement to and machining a working piece (2), comprising; - a frame (3) comprising a first end (4) and a second end (5); - a rotatable attachment device (6), which rotatable attachment device (6) is translationally movable in the frame (3), the attachment device (6) being adapted to receive a tool part (7) for machining the working piece (2); - an elongated rod (8) running through the attachment device (6), where the rod (8) is adapted to be brought from a first position (9) where it is rotationally attached in the frame (3) to a second position (10) where it is rotationally locked to the frame (3); - wherein the rod (8) comprises threads along at least a portion of its length, the threads of the rod (8) being arranged to engage with a threaded hole (11) of the working piece (2) thereby securing the rod (8) to the working piece (2), - wherein the arrangement (1) comprises a support element (12) adapted to rest against the working piece (2).

Description

TITLE OF THE INVENTION

A machining arrangement and a method for attachment to and machining a working piece.

FIELD OF THE INVENTION

The present invention relates to machining equipment and methods for attachment to and machining working pieces. In particular the invention relates to machining equipment with strong, reliable and adaptable attachment means applicable to a wide range of surfaces.

BACKGROUND OF THE INVENTION

Generally, machining equipment can be divided into two categories of use:

stationary and portable.

Stationary machining equipment usually comprises large machines for use in factories, where the machining equipment is fixed in one location and the element to be machined, the so-called working piece, is brought to the machining equipment. Stationary machining equipment allows for a controlled environment, where preparations can be undertaken to fasten and stabilize the working piece before the machining operation.

Portable machining equipment, as the name suggests, comprises machining equipment which is brought to the working piece. This can be necessary in a wide variety of field situations such as construction, assembly, offshore work, on shipyards etc. A common denominator in such field situations is often that the working piece is situated in areas that may be difficult to reach, with limited space and unfavorable conditions to rig the machining equipment. Therefore, it is often desirable to reduce the size of the machining equipment and rigging structures to a minimum.

Portable machining equipment is often made to be hand held, and therefore the machining operation can require a substantial amount of support, stability and pressure. Without a structure to attach or fasten the machining equipment to the working piece, the operator is required to provide all the support, stability and pressure by virtue of his or her body. This can be tiring work, frequently resulting in unsafe and unhealthy working positions for the operator.

Portable machining equipment in the prior art tries to solve the problem of attachment in a number of different ways, but a recurring problem is that the attachment means and methods are often ill-suited for attachment to the working piece. Sub-optimal attachment to the working piece can lead the tool of the machining equipment to catch, get stuck or work lopsided during a machining operation, or worse - the equipment can fall down and do substantial damage to personnel and property. Attempts at solving this attachment problem in the prior art, have proposed to provide an electromagnetic device on the machining equipment, the electromagnetic device providing an attraction force to the working piece and thereby acting as the attachment means. A problem with this manner of attachment is that many materials are non-magnetic, and therefore an electromagnet will be of little or no use. Another problem can arise due to failure of the electromagnet or failure of its power source, leading to the equipment falling down. Also, electromagnetic machining equipment typically requires a lengthy arrangement, unsuitable for confined spaces.

Further attempts at solving this problem in the prior art, especially for rotating tools, have proposed to provide a rod for attaching the working piece to the machining equipment. Several documents in the prior art disclose rods running through the inside of the rotating tool, below are listed 3 such examples:

U.S. patent No. 5,393, 175, 1995, Courville describes a core drill assembly for drilling a circular hole in a working piece. The drill is fastened to the working piece by using a hollow shaft which is expanded in a hole provided in the working piece . The hollow shaft has a slanted cut at the end which is fitted into the hole in the working piece, so that when the shaft is compressed, it will expand against the walls of the hole. The hollow shaft has a threaded rod running through its center, where the rod is attached by nuts at both ends of the shaft. Tightening of the nut at the end distal to the working piece will cause compression of the hollow shaft, thereby securing the shaft to the working piece. This assembly depends on the grip between the expandable shaft and the working piece being strong enough to withstand both the rotational forces of the drill, and is sufficient to support the weight of drilling assembly against the working piece.

U.S. patent No. 5,782,588, 1998, Gardner describes a core drill for drilling a circular hole in a working piece. A threaded draw bar runs through the drill assembly and the working piece, where the draw bar is fastened to the working piece by nuts on both sides of the working piece. This assembly requires access to the distal side of the working piece; therefore, it cannot be used to drill holes into structures such as tanks or other areas where it is not possible to reach the distal side of the working piece.

U.S. Patent Application Publication No . 2009/0087273, Allen, describes a core drill assembly for drilling a circular hole in a working piece. The core drill comprises a threaded feed shaft mounted in the cutting tool, where the feed shaft bores a hole in the working piece ahead of the cutting tool to guide the cutting tool. This assembly cannot be attached to the working piece before the drilling operation is started, the feed shaft is simply adapted to guide the drill, and no means for attachment between the working piece and drill assembly are provided. None of the devices or systems known from the prior art show a device where the connection of the drilling assembly to the working piece is versatile, reliable and adaptable to a wide range of surfaces.

Therefore, there is need for a machining arrangement with improved means for connection to a working piece.

SUMMARY OF THE INVENTION

In view of this, the present invention aims at providing a machining arrangement for attachment to and machining a working piece, which overcomes the drawbacks in the prior art solutions so that the means and method of attachment between the machining arrangement and the working piece is improved.

It is an object of the invention to provide a machining arrangement comprising a threaded rod running through a body of the arrangement, where the rod is adapted for attachment to a working piece.

A specific objective of the invention is to provide the working piece with a threaded hole, such that the threaded rod engages with threads in the working piece hole thereby securing stronger and simpler attachment between the machining

arrangement and the working piece.

A further objective of the invention is to provide a rod for attaching the machining arrangement to the working piece, without requiring access to the distal side of the working piece.

A further objective of the invention is provide an arrangement where the rod is easily replaceable in a frame of the arrangement.

A further objective of the invention is to provide a means for attaching and supporting the machining arrangement to the working piece, the means being shaped to correspond with the working piece, thereby giving a superior fit between the arrangement and the working piece.

The present invention provides significant improvements in relation to known solutions, as the threaded rod of the machining arrangement allows for it to be stably connected to working pieces that may otherwise be hard to reach and machine.

Accordingly, the present invention relates to a machining arrangement for attachment to and machining a working piece comprising:

- a frame comprising a first end and second end;

- a rotatable attachment device, which rotatable attachment device is translationally movable in the frame, the attachment device being adapted to receive a tool part for machining the working piece;

- an elongated rod running through the attachment device, where the rod is adapted to be brought from a first position where it is rotationally attached in the frame to a second position where it is rotationally locked to the frame;

- wherein the rod comprises threads along at least a portion of its length, the threads of the rod being arranged to engage with threads of the working piece thereby securing the rod to the working piece,

- wherein a support element is adapted to rest against the working piece during machining of the working piece.

Thus, the threads of the rod may be engaged with threads of a working piece, enabling strong and reliable attachment between the working piece and the machining arrangement. An advantageous aspect of the invention, is that the rigging of the machining equipment requires a limited amount of space and can be fitted to a large variety of surfaces, without requiring access to the distal side of the working piece. References to distal and proximal sides of the working piece, refer herein to the far and hither side of the working piece comparative to the machining

arrangement respectively. Advantageously the arrangement can be used to machine tanks and other constructions where only the proximal side is accessible. The invention also facilitates an easy and fast replacement of the rod, which can be necessary since rods of different dimensions can be used depending on the required dimension of the threaded hole in the working piece. Advantageously, the support element provides increased friction and stability against the working piece, taking up torsional forces into the frame of the machining arrangement during machining, whilst the rod provides guiding of the tool part and locking of the machining arrangement to the working piece. The support element may also be advantageous when the machining arrangement is required to be supported against a working piece with irregular shape.

In an aspect of the invention, the support element may be adapted to be releasably connected to the frame. A detachable support element may thus be fitted to the working piece prior to attachment of the machining arrangement. This may be advantageous as the support element is preferably smaller and lighter than the entire machining arrangement, thereby being more easily adjusted and fitted to the working piece such that later attachment of the machining arrangement is

facilitated. This may ease the positioning of the machining arrangement, and especially the threaded rod to the working piece and alleviate the operator of having to carry the weight of the arrangement whilst engaging the rod into the threaded hole.

In an aspect of the invention, at least a portion of the support element adapted to rest against the working piece may be provided with a semi-cylinder shaped surface, so that the support element fits a cylinder- or pipe- shaped working piece. A support element in this aspect may be especially be suited to fit with pipes or similarly shaped working pieces. In an aspect of the invention, at least a portion of the support element adapted to rest against the working piece may be provided with a surface comprising flexible padding. Advantageously the support element will thus be adaptable to the shape of the working piece.

In an aspect of the invention, at least a portion of the support element is adapted to rest against the working piece may be provided with a curable material.

Advantageously, the portion comprising curable material of the support element will be moldable to the shape of the working piece.

In an aspect of the invention, the support element may be adapted to be welded to the working piece. Advantageously, this may provide an especially strong attachment of the support element to the working piece.

In an aspect of the invention, the rotatable attachment device may be guidable along the rod in the direction of the longitudinal axis of the rod. Advantageously, this allows the tool part to also be moved with the attachment device when fitted.

Thereby, the tool may be brought into contact with the working piece during machining operations.

In an aspect of the invention, the rotatable attachment device and the elongated rod may be coaxial. Advantageously, this centres the machining arrangement around the rod and allows for a variety of different designs for the frame and driving mechanisms. The threaded rod also advantageously provides a directional and stabilizing effect for the rotatable attachment during machining operations .

In an aspect of the invention, the elongated threaded rod may be rotationally attached to the frame at a first end, and comprises said threads at a second end of the frame. Advantageously, this aspect of the invention facilitates the threaded rod being adapted to be rotated at the first end, thereby screwing the rod into a threaded hole of a working piece. The rotational attachment at the first end of the frame may comprise a nut threaded onto the rod, or similar rotational attachment means allowing for rotation of the rod and translational movement in the direction of the longitudinal axis of the rod as will be apparent to the person skilled in the art based on the disclosure of the invention herein. In some aspects, the threaded rod may be adapted to be manually rotated, though the machining arrangement may also comprise driving means for rotation of the threaded rod.

In an aspect of the invention, at least one locking device may be arranged on the threads of the rod, the locking device being adapted to provide additional attachment between the rod and the working piece. Advantageously, the locking device may comprise a nut or similar locking means, threaded on to the rod at the first end of the frame, such that the nut may be screwed against the working piece once the rod has been engaged. In aspects, the locking device may comprise a nut, or similar locking means, fitted to a distal end of the working piece from the machining arrangement, this may be advantageous in cases where the rod extends through the entire working piece and where there is access to a free end of the rod extending beyond the distal side working piece.

In an aspect of the invention, the frame may comprise an electromagnetic device adapted to rest against a surface of the working piece. Advantageously, an electromagnetic device may provide additional connectivity to a working piece comprising magnetic material. Furthermore, the electromagnetic device may be useful when positioning the machining arrangement to the working piece and alleviate the operator of having to carry the weight of the arrangement whilst engaging the rod into the threaded hole.

In an aspect of the invention, the tool part may comprise any one of: a cutting, sawing, drilling, polishing and abrasive tool. Advantageously, the tool part may comprise any of the aforementioned tools or other tools which are suited for rotation as will be apparent to the person skilled in the art based on the disclosure of the invention herein.

In an aspect of the invention, the frame may comprise a linear actuator adapted for moving the attachment device in the direction of the longitudinal axis of the rod. Advantageously, the actuator may comprise any one of: a hydraulic piston, a rack and pinion and a pneumatic actuator.

In an aspect of the invention, the arrangement may comprise an internal motor arranged to rotate the attachment device and thereby the tool part. An internal motor may be advantageous in aspects of the invention where the machining arrangement is independent of external powering means, and comprises one single device. In aspects the internal motor may comprise any one of: a hydraulic motor, a pneumatic motor and an electric motor. An electric motor may be advantageous in aspects where the arrangement requires to be battery powered. Hydraulic and pneumatic motors may be advantageous in environments containing flammable or explosive material.

In an aspect of the invention, the arrangement may be adapted to be coupled to an external motor arranged to rotate the attachment device and thereby the tool part. This aspect may be advantageous where the machining arrangement is adapted for connection with other devices, such as a standard hand drill or similar, and where the external device comprises the external motor for driving and powering the machining arrangement. According to the environment, aspects of the external motor may comprise any one of: a hydraulic motor, a pneumatic motor and an electric motor.

In an aspect of the invention, the rod may form a first attachment means for attaching the arrangement to the working piece, wherein a second attachment means is releasably connected to the arrangement. The second attachment means can allow for increased rigging of the machining arrangement to the working piece, and may comprise frames, clamps or any other well-known attachment means that are suited for rigging machining equipment to a working piece as will be apparent to the person skilled in the art based on the disclosure of the invention herein.

The invention further relates to a method for machining a working piece with a machining arrangement, the arrangement comprising a frame, a rotatable attachment device carrying a tool part for machining the working piece, and an elongated rod comprising threads along at least a portion of its length, the rod running through the attachment device, the method comprising the steps of:

- providing a threaded hole in the working piece;

- placing the arrangement over the hole, so that the rod is aligned with the hole;

- attaching the frame to the working piece by attaching the rod to the working piece by engaging the threads on the rod with the threads of the hole and then rotationally locking the rod to the frame.

By providing a threaded hole in the working piece, the threaded rod may be screwed into the whole, enabling strong and reliable attachment between the working piece and the machining arrangement. An advantageous aspect of the invention, is that the rigging of the machining equipment requires a limited amount of space and can be fitted to a large variety of surfaces, without requiring access to the distal side of the working piece. Advantageously the arrangement can be used to machine tanks and other constructions where only the proximal side is accessible. The invention also facilitates an easy and fast replacement of the rod, which can be necessary since rods of different dimensions can be used depending on the required dimension of the threaded hole in the working piece.

In an aspect of the invention, the tool part may be guided along the rod in a direction of the longitudinal axis of the rod during a machining operation.

In an aspect of the invention, the method may start with the step of:

- providing the machining arrangement with a support element, where the support element is releasably connectable to the frame and adapted to rest against the working piece during the machining operation. Advantageously, this allows a variety of different support elements to be employed, no support element may also be used.

In an aspect of the invention, the method may comprise the step of shaping at least a portion of the support element to correspond with the shape of the working piece. This aspect may be advantageous if the working piece does not have a shape that corresponds to a standard shaped support element.

In an aspect of the invention, a portion of the support element may comprise a curable material, and the step of shaping the portion begins with placing the portion of the support element against the working piece and applying heat to the material until it has a shape corresponding to the working piece. This may be advantageous if the working piece has an irregular shape, such that it is not convenient to shape a support element to correspond with the working piece in another manner.

In an aspect of the invention, the method may comprise the step of choosing the shape of at least a portion of the support element to correspond with the shape of the working piece. This may be advantageous when there is a plurality of support elements with different shapes, for example support elements that are shaped to correspond with a pipe of a particular diameter.

In an aspect of the invention, the support element may be connected to the frame of the machining arrangement prior to placing the arrangement over the hole.

In an aspect of the invention, the support element may be fitted to the work piece prior to connecting the support element to the frame of the machining arrangement. This may be advantageous as the support element is preferably smaller and lighter than the entire machining arrangement, thereby being more easily adjusted and fitted to the working piece such that later attachment of the machining arrangement is facilitated. This may ease the positioning of the machining arrangement, and especially the threaded rod to the working piece and alleviate the operator of having to carry the weight of the arrangement whilst engaging the rod into the threaded hole. Fitting the support element to the working piece may be done in using adhesive, welding or any other similar technique that will be apparent to the person skilled in the art based on the disclosure of the invention herein.

In an aspect of the invention, the threads of the hole in the working piece may engage the rod when the rod is rotated in a certain rotational direction, this direction of engagement being the opposite rotational direction of the tool part when the tool part is machining the working piece. Advantageously, the rotation of the tool part during machining operations will thus bring the threaded rod into tighter

engagement with the working piece.

In an aspect of the invention least one locking device may be fitted to the rod, the locking device being adapted to secure the working piece against rotation in relation to the rod. Advantageously the locking device may be screwed onto the rod, thereafter being screwed against the working piece to fasten the rod and working piece together. The locking device may thus preferably comprise a nut, or similar device, which may be screwed on to the threaded rod on both the distal or proximal side of the working piece.

In an aspect of the invention the locking device may comprise a pin which is connected to the rod and adapted to engage with a part of the working piece. The pin may be arranged through the threaded rod, pinching on the outside or any other similar configuration, and a groove or similar depression may be made in the working piece for engagement with the pin. Throughout the description and claims different words and terms are used, the definitions of these and other characteristics of the invention will be clear from the following description of a preferential form of embodiment, given as a non- restrictive example, with reference to the attached drawings wherein;

BRIEF DESCRIPTION OF THE DRAWINGS .

Fig. 1 schematically illustrates an aspect of the invention, where an example of a frame for a machining arrangement is shown from a side perspective with its rod in a position prior to engagement with a working piece.

Fig. 2 schematically illustrates an aspect of the invention, where a support element is shown comprising a corresponding shape as that of the surface of the working piece.

Fig. 3 schematically illustrates an aspect of the invention, where a cross section of an example of a frame for a machining arrangement is shown from a side

perspective with its rod engaged in a blind hole of the working piece.

Fig. 4 schematically illustrates an aspect of the invention, where a cross section of an example of a frame for a machining arrangement is shown from a side

perspective with its rod engaged with a working piece, where the rod extends through the working piece.

Fig. 5 schematically illustrates an aspect of the invention, where an example of the driving and displacing assemblies of the machining arrangement are presented in a cross section.

Fig. 6 schematically illustrates an aspect of the invention, where a detachable support element has been fitted to the work piece prior to attachment with the frame of the machining arrangement.

DETAILED DESCRIPTION OF THE INVENTION

The inventive concept will now be described hereinafter with reference to the examples given in the accompanying illustrations.

A machining arrangement is shown schematically in a side perspective in Fig. 1, where an example of a frame 1 is shown comprising a column 13 extending between a first end 4 and a second end 5 of the frame. At the first end 4 of the frame, the column 13 is attached to a first beam 14, wherein an elongated threaded rod 8 is rotationally mounted in a through-going hole provided in the first beam 14.

At the second end 5 of the frame, the column 13 is attached to a second beam 15. The second beam 15 is also provided with a through-going hole, sharing the same concentric axis as the hole of the first beam 14. The hole of the second beam 15 has a sufficient size to allow a rotating tool part 7 to pass through. The second beam 15 may also have a support element 12 fitted on the outside of the second beam 15 facing the working piece 2. The support element 12 may comprise a variety of different designs, however, it will also be adapted to allow a rotating tool part 7 to pass through.

Figs. 2-6 show a cross section of the support element 12 according to different aspects of the invention. Though too numerous to all be illustrated herein, the support element 12 may comprise a variety of shapes, suited to the surface and composition of the working piece. One example is shown in Fig. 2 which illustrates a support element 12 comprising a semicircular shape facing the surface of a working piece 2, wherein the working piece 2 correspondingly has a semicircular surface. Typically, for machining a pipe shaped working piece 2, a support element 12 with a corresponding semi-circular surface facing the working piece 2 may be used such as Fig. 2 illustrates.

Fig. 3 illustrates the support element 12 resting against a working piece 2 with the rod 8 engaged with the working piece 2 in the second position 10. In the examples shown in Fig. 2 and Fig. 3, the hole 11 in the working piece 2 is a so -called blind hole, as it does not extend through the working piece 2. The invention described herein is especially useful as it can be rigidly fastened to a working piece 2 by the use of a blind hole. Conversely, Fig. 4 shows the machining arrangement 1 being engaged with the working piece 2, where the rod 8 is engaged in a through -going hole 11, and the arrangement 1 may thus comprise additional fastening equipment, such as a machine support 18, on the distal side of the working piece 2.

Fig. 6 schematically illustrates an aspect of the invention where a detachable support element 12 has been fitted to the working piece 2, prior to the frame 3 machining arrangement 1 being connected to the support element 12. In this aspect, the second beam 15 and the support element 12 will have corresponding connection means 26. This aspect of the invention advantageously facilitates the support element 12 to be shaped and fitted to a working piece 2 prior to attaching the frame 3 to the support element 12. This will be beneficial if the working piece 2 has an irregular surface, or it is otherwise hard to fit the machining arrangement 1 to the working piece 2. The connection means 26 may thus comprise a click-in-place function, simplifying the connection of the frame 3 to the support element 12. In this aspect, the operator will not require to hold the machining arrangement 1 whilst simultaneously attempting to engage the threaded rod 8 into the hole 11 of the working piece 2. The support element 12 may also be welded, or fitted with adhesives or other similar solutions, to the working piece 2 prior to connecting the frame 3 to the working piece 12.

Additionally, second attachment means may also be provided on the frame 3 of the machining arrangement 1. Though the second attachment means are not shown herein, Fig. 1 illustrates second connection means 21 for connecting a second attachment means to the frame 3. The second connection means 21 may comprise holes, threaded holes or any other connection means that are known to the person skilled in the art. The second attachment means are fitted between the second connection means 21 and the working piece 2, and provide extra fastening between the machining arrangement 1 and the working piece 2, and may comprise an external frame, a clamp or similar rigging equipment. Secondary connection means 21 may also arranged on the support element 12, or other suitable areas of the frame 3 as will be apparent to the person skilled in the art based on the disclosure of the invention herein.

A third beam 16 is perpendicularly and displaceably mounted in the column 13 and extends on either side of the column 13. The third beam 16 also comprises a hole sharing a concentric axis with the holes of the first beam 14 and the second beam 15. In the hole of the third beam 16, a rotatable attachment device 4 is mounted, sharing a concentric axis with the aforementioned holes of the first 14 and second beams 15. The rotatable attachment device 4 may comprise a chuck, clamp or similar attachment device, suited to attach a tool part 7 for rotational machining of a working piece.

In other aspects of the invention not illustrated herein, the first 14, second 15 and third 16 beams may be attached to a second column, whereby the ends of the first 14 and second 15 beams ends are connected to respectively the first and second ends of the second column, whilst the third beam 16 is displaceably mounted in the second column. Yet further variations of the frame are possible within the scope of the claims, and are not explained or illustrated in further detail herein as they are too numerous and will be obvious to the person skilled in the art based upon the disclosure of the invention herein.

Running through the aforementioned holes of the three beams, the elongated threaded rod 8 is arranged concentrically inside the attachment device 4 and tool part 7. In Fig. 1 , Fig. 2, Fig. 5 and Fig. 6 the elongated threaded rod 8 is shown in a first position 9, where the rod 8 may be rotationally mounted in the hole of the first beam 14. In the first position 9 the rod 8 may also be displaceable in the

longitudinal direction of the rod 8. The rotational attachment of the rod 8 at the hole in the first beam may comprise a nut 17, as illustrated in Fig. 1 , or any similar arrangement allowing for both linear and rotational displacement of the rod 8. In this aspect, the rod 8 may therefore be threaded along its entire length, however, the rotational attachment at the first end 4 of the frame 3 may be accomplished by other means known in the art. Thus, the rod 8 is usually displaced towards the first end 4 of the frame 3 in the first position 9, and may be displaced towards the second end 5 of the frame 3 and engaged with the working piece 2 in the second position 10, as illustrated in Fig. 2.

The working piece 2 in Fig. 1 is shown in a cross sectional view to illustrate the threaded hole 11 with which the rod 8 of the machining arrangement 1 is adapted to engage by screwing the rod 8 into the working piece 2. Thus, the rod 8 constitutes the principal attachment means for attaching the machining arrangement 1 to the working piece 2. In aspects of the invention, the rod 8 may be manually operated, i.e. it is manipulated and screwed by hand to engage with the working piece 2.

Whilst in other aspects, a driving mechanism may be arranged in the first beam 14 to automatically rotate or displace the rod 8. In an aspect, the rod 8 and the threaded hole 11 in the working piece may be provided with threads allowing engagement when the rod 8 is rotated clockwise. In this aspect the rotation of the tool part 7 will preferentially be counter clockwise during machining, thus ensuring that the rod 8 is not disengaged during machining of the working piece 2. In other aspects the rod 8 and hole of the working piece may be arranged for engagement when the rod 8 is rotated counter-clockwise, and the tool part 7 is rotated clockwise during the machining operation.

Fig. 3 displays an example of the machining arrangement with the rod 8 in the second position 10; the rod 8 is engaged with the threaded hole 11 of the working piece 2, and the nut 17 at the first end is tightened to rotationally lock the rod 8 to the first beam 14. A cross section of the support element 12 and working piece 2 are shown in Fig. 3, together with a machine support 18 also shown on the distal side of the working piece 2. On the proximal side of the working piece 2, a locking device 19 on the rod 8 exemplified as a nut, provides additional engagement between the working piece 2 and machining arrangement 1. Likewise, the machine support 18 is locked to the working piece by a nut 19 on the rod 8. The working piece 2 and machine support 18 each display a hole 22 located besides the axis and separated from threaded hole 11 , this hole 22 may be used to pass through fluids. The fluids may be for lubrication, and to clear the inner space of the support element 12 of shavings and filings.

In other aspects, not illustrated in the figures, the locking device 19 on the proximal side of the working piece 2 may take the form of an element running

perpendicularly to the longitudinal direction of the rod 8. For example, the locking element 19 may comprise a clamping or clasping device such as a clip, comprising two metal pieces adapted to press together over the rod 8. In this aspect, the rod 8 may preferentially be provided with cutting-outs allowing the clamping device to engage with the rod 8 without being free to rotate around the rod 8. In further aspects, the rod 8 may be provided with a hole running perpendicularly to the longitudinal direction of the rod 8. The locking element 19 may in these aspects comprise a pin to be inserted into the perpendicularly running hole, and the working piece 2 comprises a part that will engage the pin, thereby securing the rod 8 against rotation relative to the working piece. The part of the working piece 2 adapted to engage the rod 8 may comprise a screw, a bolt, a nail, a piece screwed to the working piece 2, or any otherwise projecting element that may be an integrated or fitted part of the working piece 2. The part of the working piece 2 adapted to engage the pin may also comprise a cutting-out, surrounding the threaded hole 11. Such that a pin or otherwise transverse element of the rod 8 will engage with a part of the working piece 2 as the rod 8 is threaded into the threaded hole 11.

An example of a possible driving mechanism of the machining arrangement is schematically illustrated in Fig. 5. The displacement mechanism of the third beam 3 is exemplified as rack and pinion gear. The rack 23 comprises a linear gear bar, and may be mounted along the length of the column 13. The pinion gear 24 comprises a traditional circular gear and may be mounted in the third beam 16 engaging the rack 23 on the column 13. Rotation of the gear 24 mounted in the third beam 16 will therefore cause the third beam 16 to be displaced along the column 13. The linear actuator may be powered by a manual hand crank or a motor driving mechanism according to what is most suitable. It will be obvious to the person skilled in the art based on the description of the invention herein that any other suitable linear actuator and powering arrangement of the actuator may be employed for the same purposes, such as hydraulic or pneumatic pistons.

As the rotatable attachment device 6 is mounted in the third beam 16, displacing the third beam 16 correspondingly guides the attachment device 6 and tool part 7 along the rod 8 in the direction of the longitudinal axis of the rod 8. Accordingly, the tool part 7 is advanced into, or out of, the working piece 2 during a machining operation.

In other aspects of the invention, where the arrangement comprises a plurality of columns, a second column may have a similar second linear actuator, mirroring the first linear actuator of the first column. However, the second column does not necessarily comprise a second linear actuator, whereby the third beam is simply displaceable in the second column, which is provided for support rather than to give additional power to the displacing system.

Fig. 4 furthermore illustrates an example of how rotational movement to the tool part 7 may be provided by a driving gear 25 mounted in the third beam 16. The driving gear 25 is connected to the attachment device, e.g. a chuck. The chuck is adapted to engage a tool part 7 such as a drill, saw or other cutting tool. The chuck may also receive other tool parts 7 adapted for grinding, sanding or other abrasive operations. The driving gear 25 in Fig. 4 is in engagement with a toothed belt 26 which drives the gear 25 and extends through and along the longitudinal axis of the third beam 16, past the column 13 to an input gear 27 located at the distal end (to the attachment device ) of the third beam 16. In other aspects, the driving gear 25 may form part of a bevel gear, whereby the driving gear 25 engages with a gear mounted on a shaft, the shaft running through and along the longitudinal axis of the third beam 16, past the column 13 to an input gear 27 located at the distal end of the third beam 16.

The input gear 27 may be connected to a driving shaft 28 of a motor, which may be internally integrated into the machining arrangement 1 by arranging the input gear 27 to be coupled to the driving shaft 28 which comprises an output shaft of the motor. In other aspects, the input gear 27 may have a connector for coupling an external motor to the input gear 27. The connector may comprise a shank or other type of shaft suitable for coupling to a power tool, or other external motor.

Now will be given some examples of the machining operation, according to different aspects of the invention as illustrated in Figs. 1 -4.

Prior to positioning the machining arrangement against the working piece 2, a suitable support element 12 is provided to rest against the working piece 2. Though it should be noted, in some aspects of the invention, a support element 12 may be permanently fitted to the frame 3, or there may be no need for a support element 12 for certain machining operations. The support element 12 can be shaped at the site of the machining operation, or it may be pre-prepared. Shaping the support element 12 can be done in a number of ways, as will be familiar to the person skilled in the art, such as cutting out or grinding down the element 12 to a shape that will fit to the working piece 2, or provide a surface with increased friction. Preferably, the surface of the working piece 2, to where the support element 12 is to be fitted will also be prepared, e.g. to provide increased friction. In some aspects of the invention, exemplified in Fig. 6, the support element 12 is fitted to the working piece 2 prior to fitting the support element 12 to the frame 3 of the machining arrangement 1.

If the shape of the working piece is irregular, it is conceivable that a mold can be taken of the working piece's 2 surface, such that support element 12 can be made by casting a support element 12 in the mold. In another aspect, the support element 12 may be fitted to the working piece 2 by providing a support element 12 where a part of the support element 12 consists of a curable material, for example a

thermoplastic. In this aspect, the portion of the support element 12 may be placed up against the working piece 2, and heat is applied to cure the material and thereby fitting the support element 12 to the working piece 2.

In aspects of the invention, the threaded hole 11 is made before any parts of the machining arrangement 1 , including the support element 12, are fitted to the working piece 2. The size of the rod 8, and the size and pitch of the threads of the rod 8 are chosen according to the torque requirements for the machining operation, the equivalent dimensions of the threaded hole 11 can thereafter be found and a suitable drill and tap can be chosen to create the threaded hole 11. A hole is then drilled in the working piece 2, the hole may either pass through the working piece 2 or comprise a blind hole. Thereafter, a tap is screwed into the hole, producing the desired threads in the hole. In some aspects of the invention, the machining arrangement may have means to accommodate a drill, tap and die to the rotatable attachment device, which may require temporarily replacing the rod 8. In these aspects the machining arrangement 1 may either be hand-held against the working piece 2, during the operation of making the threaded hole 1 1 , or fitted in some other way e.g. by a pre-fitted support element 12 as mentioned earlier. In some aspects of the invention a lubrication hole 22, may be made next to the threaded hole 11, also prior to the machining operation.

Prior to engaging the rod 8, a tool part 7 is chosen according to the machining operation to be performed, and fitted in the rotatable attachment device 6.

Fig. 1 and Fig. 4 show examples of a machining arrangement as it is being placed over the threaded hole 1 1, with a support element 12 being already arranged on the frame 3, and where the threaded hole 11 and the rod 8 are aligned along a common axis. In these aspects, the rod 8 is then moved from a first position 9 and down towards the hole 11, where the rod 8 is screwed into the hole 11, thereby engaging and locking the rod 8 in the second position 10.

Fig. 3 and Fig. 4 show examples of a machining arrangement 1 after the rod 8 has been screwed down to a sufficient length, the rod 8 is rotationally locked in the first end 4 of the frame 3 and is in the second position 10. The tool part 7 is then ready to machine the working piece 2. In the aspect illustrated in Fig. 4 a locking device, exemplified as a nut 19, has been screwed onto the rod 8, prior to the rod's 8 engagement with the working piece 2, whereby the nut 19 can be tightened against the working piece 2 after the rod 8 has been engaged in the second position 10 thereby providing additional rotational locking of the machining arrangement 1 to the working piece 2. An aspect of the invention exemplified in Fig. 4 also illustrates the rod 8 passing through the working piece 2 beyond the distal side and further through a machine support 18, which is locked to the working piece 2 by another locking device 20, exemplified as nut, threaded onto the rod 8.

Fig. 7 illustrates an embodiment of the invention in a perspective view. In contrast to the embodiments of Figs. 1-6, the frame 3 in this embodiment comprises a cylindrical housing 3 where a rod 8 extends from a first end 4 of the housing 3 to a second end 5. Accordingly, the frame 3 does not necessarily comprise a first beam 14 and second beam 15, but rather the cylindrical housing 3 takes the place of the column 13, first beam 14 and second beam 15. The rod 8 can thus be rotationally attached and/or locked to the rotational attachment plate 19 at the first end 4 of the cylindrical housing 3. Inside the cylindrical housing 3, the rod 8 runs through a gear 25, an attachment device 6 exemplified as a chuck and a tool part 7 exemplified as a circular blade. The gear 25 is coupled to the attachment device 6 for driving of the tool part 7, and is powered through an angular gear 26, corresponding to the toothed belt 26 of the other embodiments, in the third beam 16. The third beam 16 is connected to the cylindrical housing 3 via a pinion gear 24 coupled to a linear gear bar 23 mounted on the cylindrical housing 3, thereby allowing the third beam 16, gears 25,26 and consequently the tool part 7 to move translationally in the frame 3 along the rod 8. The pinion gear 24 is exemplified as being connected to a hand crank for driving the gear 24. A support element 12 is shown attached to the second end 5 of the cylindrical housing 3, partially attached around the perimeter of the housing 3, except for a recess 29 in the housing designed to let out shavings during machining. The support element 12 is shaped with a corresponding cylindrical shape to that of the housing 3, such that the tool part 7 can pass through the support element 12 and into a working piece 2. The support element 12 is thus arranged to rest against a working piece 2, and to take up torsional forces acting on the machining arrangement 1 during machining, whilst the rod 8 locks the arrangement 1 to the working piece 2 and provides guiding for the tool part 7 during machining.

The invention is herein described in non-limiting embodiments. A person skilled in the art will understand that there may be made alterations and modifications to the embodiments that are within the scope of the invention as described in the attached claims.

REFERENCE LIST TO THE DRAWINGS

1. Machining arrangement

2. Working piece

3. Frame

4. First end of frame

5. Second end of frame

6. Rotatable attachment device

7. Tool part

8. Elongated threaded rod

9. First position

10. Second position

11. Threaded hole

12. Support element

13. Column

14. First beam

15. Second beam

16. Third beam

17. Rotational attachment

18. Machine support

19. Locking device

20. Second locking device

21. Second connection means

22. Lubrication hole

23. Linear gear bar

24. Pinion gear

25. Driving gear

26. Toothed belt

27. Input gear

28. Driving shaft

29. Recess

Claims

1. A machining arrangement (1) for attachment to and machining a working piece (2) comprising;

- a frame (3) comprising a first end (4) and a second end (5) ;

- a rotatable attachment device (6), which rotatable attachment device (6) is translationally movable in the frame (3), the attachment device (6) being adapted to receive a tool part (7) for machining the working piece (2);

- an elongated rod (8) running through the attachment device (6), where the rod (8) is adapted to be brought from a first position (9) where it is rotationally attached in the frame (3) to a second position (10) where it is rotationally locked to the frame (3) ;

- wherein the rod (8) comprises threads along at least a portion of its length, the threads of the rod (8) being arranged to engage with a threaded hole (11) of the working piece (2) thereby securing the rod (8) to the working piece (2),

- wherein the arrangement (1) comprises a support element (12) adapted to rest against the working piece (2).

2. The machining arrangement (1) according to claim 1, wherein the support element (12) is adapted to be releasably connected to the frame (4)

3. The machining arrangement (1) according to any of the preceding claims, wherein the attachment device (6) is guidable along the rod (8) in the direction of the longitudinal axis of the rod (8).

4. The machining arrangement (1) according to any one of the preceding

claims, wherein the elongated threaded rod (8) is rotationally attached to the frame (3) at a first end, and comprises said threads at a second end of the frame (5).

5. The machining arrangement (1) according to any one of the preceding

claims, wherein the tool part (7) comprises any one of: a cutting tool, a sawing tool, a drilling tool, a polishing tool and an abrasive tool.

6. A method for machining a working piece (2) with a machining arrangement

(1), the arrangement (1) comprising a frame (3), a rotatable attachment device (6) carrying a tool part

(7) for machining the working piece (2), and an elongated rod (8) comprising threads along at least a portion of its length, the rod (8) running through the attachment device (6), the method

comprising the steps of:

- providing a threaded hole (11) in the working piece (2);

- placing the arrangement (1) over the hole (11), so that the rod (8) is aligned with the hole (13);

- attaching the frame (3) to the working piece (2) by attaching the rod (8) to the working piece (2) by engaging the threads on the rod (8) with the threads of the hole (11) and then rotationally locking the rod

(8) to the frame (3).

The method according to claim 6, the method starting with the step of:

- providing the machining arrangement (1) with a support element (12), where the support element (12) is releasably connectable to the frame (3) and adapted to rest against the working piece (2).

The method according to claim 7, wherein the support element (12) is connected to the frame (3) of the machining arrangement (1) prior to placing the arrangement (1) over the hole (11).

9. The method according to claim 8, wherein the support element (12) is fitted to the working piece (2) prior to connecting the support element (12) to the frame (3) of the machining arrangement (1).