BACKGROUND ART When working with tools with handles, having an upper handle part and a lower tool part, it is often important to be able to change the tool part easily. This applies especially when large areas are to be covered and having several complete tools would therefore be unnecessarily bulky and heavy to move. This is the case with cleaning work, for instance, where the predominant work procedure is dry and wet mopping of floors with the aid of so-called cleaning handles. During such work, there is a need to be able to change the tool part, the so- called rack, depending on the type of floor cleaning that is to be performed. It is also desirable to be able to use the same handle part for window cleaning, which requires another kind of tool part.

Occasionally, there is also a need to be able to connect an intermediate part, to extend or angle the handle, between the handle part and the

tool part. Different kinds of connections between the various parts are available. For instance, connections are commercially available in which the handle part is provided at its lower end with a threaded element that is screwed onto a corresponding threaded element on the tool part. However, the most common connection is a type where the handle part is provided at its lower end with an outer element, usually in the form of a tube, with a circular cross-section, into which an inner element, cohesive with the tool part or the intermediate part, can be inserted. The inner element is most commonly fashioned as a tube with an outer diameter slightly smaller than the inner diameter of the outer element. In some cases, the tool part is provided with an outer element into which an inner element on the lower end of the handle part can be inserted. The most common method of locking the parts to each other is to employ a cotter joint, which in its simplest form consists of a pin inserted from the outside through radially directed grooves in the inner and the outer elements. This provides a secure and cheap coupling but has the disadvantage that the pin easily can be lost when the coupling is opened. There is a more developed variation of the cotter joint, especially for cleaning tools, that is so widespread that it is regarded as standard on the market. Its inner element comprises a separate locking member in the form of a U-shaped spring piece, which is provided at it ends with outwardly directed locking dowels, the upper/outer ends of which act as control buttons. The locking member is inserted into a cavity in the inner element, which is provided with radially directed guide grooves for the locking dowels. The locking dowels thus protrude through the envelope surface of the inner element and are influenced by an outward radial force from the U-spring. The locking dowels also comprise an inner part with a cross-section greater than that of the guide groove.

Actuated by the spring force, the locking dowels are thus pressed towards an outer locking position. The outer element is provided with corresponding radially directed locking grooves. When a tool part is being connected, the inner element is inserted into the outer element

in the axial direction up to the position where the locking dowels encounter the outermost edge of the outer element. The locking dowels are then pressed in towards the centre of the inner element.

The upper parts of the locking dowels then serve as control buttons for the thumb and an opposite finger of the operator. The inner element is simultaneously inserted into the outer one, whereupon the control buttons slide into the space between the inner and the outer elements.

Thereafter, the inner element is displaced/turned to the locking position, whereupon the control buttons and the subjacent locking dowels are pressed out by the spring through the locking grooves in the outer element. If inserting the inner element into the outer one involves friction, this will present a risk of injury, especially as the outer element ordinarily is a tube with an outer edge that is relatively sharp. A particularly great risk of injury arises during the disengagement process when the upper parts of the locking dowels must be pressed into the locking grooves while, simultaneously, the inner and the outer elements are pulled apart. The fingertips of the operator must then be located in the space between the inner and the outer elements while, simultaneously, a relatively large tractive force is applied. When the parts then disengage from each other, often suddenly, there is a great risk of the fingertips being jammed between the usually sharp edges of the guide groove and the locking groove with consequent cutting injuries. Making the locking dowels higher does not help, as they must still be pressed into the space between the inner and the outer elements. An attempt to alleviate the problem described above is to introduce locking dowels with a bevelled edge.

This works poorly, however, as the corresponding edges of the locking groove are ordinarily unbevelled, for reasons of cost, and the locking dowels thus do not slide in under the space between the inner and the outer elements as easily as intended. Apart from the risk of injury, the coupling is difficult to operate, as the control buttons are small to be able to clear the locking groove, the size of which is limited. For the aforementioned reasons, the control buttons must additionally be

pressed into a depression, which renders control yet more difficult. A further disadvantage with this solution is that it is costly, as the locking member consists of a separate part that must be manufactured, stocked, and assembled.

DESCRIPTION OF THE INVENTION The primary object of the present invention is to provide a connection in accordance with the preamble that can be manipulated without risk of injury to the operator.

Another object of the invention is to provide a connection that is easy to access and to manipulate.

Yet another object of the invention is to provide an efficient connection that can be manufactured at a low cost.

These objects are achieved with a connection for detachably locking different parts on a broom handle or similar work tool, such as a handle part and a tool part, where the connection comprises an outer element on the one part and an inner element on the other part, the inner element being inserted into the outer element when the parts are coupled together, like tubes of different diameters, the outer element comprising radially directed locking grooves and the inner element comprising one or several outwardly spring-loaded locking dowels, which, in the locked position, engage the locking grooves of the outer element, as well as one or several control buttons, which, for disengagement, are depressed towards the inner element, whereupon the locking dowels are released from the locking groove and the inner element can be extricated from the outer element, the control buttons being completely or partially located outside the space between the inner and the outer elements when these elements are inserted into or extricated from each other.

The invention will now be further described with reference to the following drawings, which are intended to explain and not to limit the invention, of which Figure 1 is a partial view of a handle part; Figure 2 shows a handle part for floor mopping with a connection part in accordance with the invention; Figure 3 is a partial view of an outer element; Figure 4 is a partial view of an inner element in a preferred embodiment in accordance with the invention; Figure 5 is an end view of the inner element in accordance with Figure 4; Figure 6 shows a section of the outer element, viewed from the side; Figure 7 is a half-section of the inner element, viewed from the side; Figure 8 is a section showing, from the side, the inner element partially inserted into the outer one; Figure 9 is a section showing, from the side, the inner element when the locking dowels are in the space between the inner and the outer element; Figure 10 is a section showing, from the side, the connection between the inner and the outer elements in accordance with Figure 9 in a locked position;

Figure 11 is a view showing the connection in accordance with Figure 10 above; Figure 12 is various views showing a locking member in accordance with the invention; Figure 13 is a partial section showing, from the side, the locking member in accordance with Figure 12 while being introduced into the inner element; Figure 14 is a view from above of details in accordance with Figure 13; Figure 15 is a half-section showing the locking member in accordance with Figure 12 introduced into the inner element; Figure 16 is a view from above showing details in accordance with Figure 15; Figure 17 is a view from above of a variation of the outer element; Figure 18 is a view from above of an inner element with a locking member mounted in a position preparatory to engagement; Figure 19 is a lateral view, partially sliced through, showing the inner element in accordance with Figure 18 partially inserted into the outer element in accordance with Figure 17; Figure 20 is a view from above showing the connection in accordance with Figure 19 in a locked position; Figure 21 is a view from above of an inner element with spring locking dowels, fashioned in one piece with the same;

Figure 22 is a section of an inner element in accordance with Figure 21, seen from the side; Figure 23 is a view from above showing a connection device comprising an inner and an outer element in accordance with the invention; and Figure 24 is a view from above showing a variation of a device in accordance with Figure 23, where the spring locking dowels with the control buttons are manufactured in one piece with the inner element.

The invention can be applied to all kinds of tools provided with a handle where there is a need to be able to change the tool part easily, such as gardening tools, paint shanks and the like. The primary area of application, however, is broom handles for floor and window cleaning and particularly those intended for dry and wet mopping of floors.

Figure 1 shows a broom handle for dry mopping of floors, the tool part 4 being disengaged from the handle part 1, only partly shown. The lower end of the handle part 1 comprises a tubular outer element 2, provided with radially directed locking grooves 3 in the form of two through-running opposite holes in the envelope surface. An inner element 5 is connected to the tool part with conventional cardanic suspension. Preferably, the handle part comprises the outer element and the tool part the inner element, but the opposite can also be the case, of course.

Figures 3-7 show a preferred embodiment of the essential parts of a connection in accordance with the invention. The outer element 2 consists of a tube with a circular cross-section. The material can be metal or reinforced plastic. Locking grooves 3 are cut out near the end.

Preferably, the locking grooves consist of holes that pass through the envelope surface of the outer element on two opposite sides in a conventional way. These locking grooves are made by drilling or

punching and thus acquire unavoidably sharp edges, at least on one side. An inner element 5, suitably manufactured of injection-moulded plastic, comprises a tube part 12 with a circular cross-section having an outer diameter slightly smaller than the inner diameter of the outer element 2. A groove 7 is cut through the envelope surface of the tube part 12 in such a way that a tongue is formed. This tongue comprises a spring 6, fashioned in one piece with and of the same material as the tube part 12, an outwardly radially directed locking dowel 8 with a shape adapted to the locking groove 3, and a control button 10, cohesive with the locking dowel 8 by way of an arm 9. The control button 10 can be provided with coring-out to reduce the material thickness, thus facilitating manufacture. The rear tube part 11 of the inner element 5 has an outer diameter that is suitably greater than the tube part 12 and thus forms a stop edge when the inner element 5 is inserted into the outer element 2.

The front edge of the control button 10 is located level with the front edge of the tube part 11 and will therefore always be easily accessible outside the outer element 2. Preferably, the inner element 5 has the same locking device on the opposite side with a spring 6, a locking dowel 8, an arm 9, and a control button 10, as illustrated in Figures 5 and 7, so that a double locking mechanism is provided, but one or more than two locking devices can obviously also be considered. An essential advantage of an inner element 5 in accordance with the description, where the spring 6, the locking dowels 8, and the control button 10 are manufactured in one piece with the inner element, is that the production costs are reduced considerably. The reason for this is that no separate locking member has to be manufactured, stocked, or assembled. Another important advantage is that the locking member is manipulated outside the outer element in accordance with Figure 8.

In this context, the inner element 5 is inserted, in the axial direction, into the outer element 2, at the same time as the control buttons 10 are depressed towards the centre in the direction of arrows A. The locking

dowels 8, acted upon by the arms 9, are then also depressed in towards the centre to such a position that they can freely clear the space between 15 between the inner and the outer elements, as shown in Figure 9. Thereafter, the inner element 5 is displaced/turned to the locking position, whereupon the locking dowels 8 are pressed out, by the spring, through the locking grooves 3 in the outer element 2, which is illustrated in Figures 10 and 11. Engagement is facilitated if the anterior edge of the outer element 2 is upset outwards or worked in some other way so that a bevelled entry for the locking dowels is formed, which is not shown in the drawings. The inner element 5 can then be displaced to the locking position without the control buttons 10 having to be depressed towards the centre. During disengagement, the control buttons 10 are depressed in towards the centre of the inner element 5, whereupon the locking dowels 8 are released from the locking grooves 3 and the inner element 5 can be withdrawn from the outer element 2. During engagement as well as disengagement of the two elements 2 and 5 in accordance with the invention described above, the control buttons 10 remain outside the space 15 between the inner element 5 and the outer element 2. These control buttons 10 can therefore be manipulated by the fingers of the operator without any risk of injury. Moreover, they can be made higher and designed with a greater and more comfortable depression surface than would otherwise be possible. Besides the risk of injury being eliminated, they thus become more easily accessible and easily manipulated than known commercially available alternatives.

Figure 12 shows various views, in accordance with European viewpoint conventions, of a separate locking member 17 in accordance with the invention. The locking member 17 is suitably manufactured of injection-moulded plastic and consists, in its essence, of a U-shaped spring with locking dowels 8 and control buttons 10 at both free ends of the spring 6. The depression surface of the control buttons 10 extend towards the locking dowels 8 in a tapered portion 19. Stop surfaces 22

are fashioned below this portion 19. Coring-outs 18 are located on the underside of the control buttons 10, which is advantageous for production-engineering reasons. The locking member 17 is primarily intended for inner elements 5 manufactured of metal tubes, which cannot easily be provided with locking members fashioned in one piece with the same. During assembly, the locking member 17 is compressed and inserted into the space 13 in the inner element 5, in accordance with Figure 13 and 14. The inner element 5 is provided with an axially directed guide groove 20, suitably by punching. Figures 15 and 16 show a ready-assembled inner element 5, where the locking dowels 8 and the control buttons 10 are situated in the guide groove 20, with some clearance, and, actuated by the spring 6, are pressed to an outer locking position defined by the stop surfaces 22. Figures 17 and 18 show an outer element 2 and an inner element 5 in accordance with the above, in a preparatory assembly position. The locking groove 3 is provided with a gap 21, which gap constitutes an opening between the end of the outer element and the locking groove. The gap 21 is designed such that it corresponds, with suitable clearance, to the portion 19 on the control button.

The advantage of this design is that the control buttons 10 are closer to the locking dowels 8, without having to be pressed into the space between the inner and the outer elements during the assembly procedure.

Another advantage is that the gap 21 acts as a guide during engagement, making it easier to find the locking position. During the assembly procedure, in accordance with Figure 19, the control buttons 10 are depressed in the direction of arrows A, whereby the locking dowels 8 are depressed to such a position that they can freely clear the space 15 between the inner and the outer elements. Thereafter, the inner element 5 is inserted into the outer element 2 to a locked position in accordance with Figure 20, whereupon the locking dowels

8 are pressed out, by the spring 6, through the locking grooves 3 in the outer element 2. During disengagement, the control buttons 10 are depressed towards the centre as previously. The locking dowels 8 are thereby released from the locking grooves 3 and the inner element 5 can thereafter easily be withdrawn from the outer element 2. This coupling also exhibits the advantage of easy and safe manipulation, as the control buttons 10 remain located outside the space 15 between the inner element and the outer element during engagement as well as during disengagement. A further advantage of a separate locking member 17 in accordance with the above is that it can be assembled on inner elements 5 of varying shapes and dimensions, whereby investment costs for the means of production can be reduced.

Preferably, the control button 10 comprises a section that remains located axially outside the end of the outer element in the connected position, as previously described. However, an alternative embodiment can also be considered where the control button 10 is fashioned as a narrow rod that is long in the axial direction and placed above the locking dowel 8, as an extension of the tapered portion 19 in accordance with Figure 12. If the thus rod-shaped control button 10 is narrower than the locking dowel 8, the control button can pass freely through a gap 21 between the locking groove 3 and the end of the outer element 2 without impairment to the operation of the lock. In this embodiment, the control button 10 has a smaller depression surface than in the embodiments previously described. However, during engagement as well as during disengagement, the depression surface on the control button remains located radially outside the space 15 between the inner element and the outer element. Thus, this embodiment also exhibits the significant advantage of easy and safe manipulation.

Figures 21 and 22 show an inner element 5 with a spring 6 and a locking dowel 8, in one piece with the same, in accordance with the

embodiment depicted in Figures 4 and 5. In this case, however, the locking dowel is manipulated by way of its upper part acting as a control button in accordance with known technology. This design is still superior as regards production technology to commercially available alternatives.

Figures 23 and 24 show coupling devices, comprising an inner element 5 at one end and an outer element 2 at the other end. These two elements are joined in one piece with a conical part 22. In the embodiment in accordance with Figure 23, the coupling device is manufactured of a metal tube that has been tapered down to an inner element 5 and provided with a separate locking member 17 as previously described. In the embodiment in accordance with Figure 24, the coupling device is manufactured of injection-moulded plastic, with a locking member 6,8,9,10 in one piece with the inner element 5 as previously described. In both these embodiments, the outer element is provided with a locking groove 3 as previously. Such coupling elements can be permanently connected to parts, often tool parts, with inner elements of a conventional design, such as are in use in great numbers. Thereby, these parts can also be easily and safely connected and disengaged.

DESCRIPTION OF THE FURTHER DEVELOPMENT OF THE INVENTION A tool, known as a rack, is used for dry and wet mopping of floors. The rack is attached to the connection part with a gimbal mount that enables rotation of the rack while the same is in contact with the floor.

The rack is thus pivoted in relation to the handle with two axes that are at 90 degrees to each other. Sometimes, it may be necessary to be able to lock one of the rotational axes, so that the rack advances along the floor but cannot rotate about an axis perpendicular to the surface of the floor.

Figures 25 and 26 show a rack 51 attached to a connection part 5 via a gimbal mount 52. This consists of an attachment piece 53, which is screwed onto the rack. The attachment piece 53 is provided with two opposite bottom holes into which corresponding pins 55 are received.

These pins 55 are attached to a universal joint 54, which universal joint can thus rotate in the direction of arrow B. The universal joint 54 is provided with a hole, the centre line of which is turned 90 degrees relative to the axis of the pins 55. A shaft 57 is inserted into the hole, which shaft is attached to a fork 56, whereby the fork 56 can rotate in the direction of arrow A.

It is the rotation in the direction of arrow A that sometimes needs to be locked. A blocking member in the form of a T-shaped metal piece, the shaft of which is introduced into a central hole in the connection part 5 is commercially available. When the universal joint is locked, the metal piece is pulled out towards the universal joint and locked by turning the metal piece, whereby locking shoulders engage the underside of the connection part 5. This solution has the disadvantage that the metal piece is expensive to manufacture and difficult to assemble. In addition, it is not easily comprehensible to the operator and is difficult to handle, as several different movements are required for it to be operational.

These disadvantages are eliminated with a device in accordance with the invention, which consists of a blocking member 58, pivotably attached to the underside of the connection part 5. The fork 56 is thus provided with protrusions 59, forming an internal cylindrical envelope surface. A cylindrical peg 60 is inserted into this surface, which peg constitutes the upper part of the blocking member 58. These parts 58 and 59 can easily be manufactured of reinforced plastic by using an uncomplicated injection-moulding tool or, with minor modification, the existing injection-moulding tool for the connection

part 5. The blocking member 58 is also particularly easy to assemble, as it can be introduced from the side. Thus, the assembly process can easily be automated, which is desirable, bearing in mind the large volume of such tools that are manufactured. On a conservative estimate, the manufacturing costs are 25 per cent of the costs for existing blocking members. To the operator, manipulation is easy.

When blocking is desired, the blocking member 58 is turned down towards the universal joint 54, as illustrated in Figures 27 and 28. The lower locking surface of the blocking member thereby engages the upper surface of the universal joint, thus preventing rotation in the direction of arrow A in accordance with Figure 25. In addition, the manipulation process is easily comprehensible.

This embodiment is preferred, as it does not prejudice the mobility of the gimbal mount, but a pivotable blocking member attached to the upper surface of the universal joint is, of course, also conceivable, which member acts upon one of the legs of the fork 56 or upon the underside of the coupling member 5.

DESCRIPTION OF ONE EMBODIMENT OF THE INVENTION Figures 29-35 show an embodiment with a separate locking member 17 that is fitted into an externally open groove in the inner element 5.

This variation has the following advantages. The locking member is easily assembled and can be manufactured so that pre-tensioning is provided when it is fitted into the outer element 2, which is difficult to achieve if it is manufactured in one piece with the inner element. The locking member in accordance with Figures 12-20 also exhibits these desirable qualities, but in that embodiment the locking member is mounted by being pressed together and introduced into the space 13 in the inner element 5 in accordance with Figures 13 and 14. As the outer diameter of the inner element 5 is standardized at 20 mm in large parts of the market for broom handles, the width and height of the control

buttons 10, which must fit inside the space 13 during assembly, are thereby limited. This disadvantage is eliminated by the design in accordance with Figures 29-35. Figure 29 and the left part of Figure 32 show a separate locking member, somewhat pulled apart, with a substantially U-shaped spring 6 and locking dowels 8 and control buttons 10 at both free ends of the spring 6. The locking member is further provided with protrusions 71 and a guide groove 75. The locking member 17 is suitably manufactured of injection-moulded plastic. Figures 30 and 31 show an inner element 5 with a dowel- shaped end 70, intended to be inserted into an outer elements 2. The cross-section of the end 70 is thus fashioned so that is fits into the desired outer element. Figures 30 and 31 show a circular cross-section.

This cross-section is interrupted by outwardly open longitudinal grooves 73, intended for the locking member 17. The end 70 is thereby fashioned as an H-beam, the outer end of the waist 74 of which acts as a guide edge for the guide groove 75 of the locking member 17.

Furthermore, the guide groove 73 is provided with lateral groove 72, adapted to the protrusions 71 of the locking member 17. Figure 32 shows a preparatory assembly position, where the locking member 17 is somewhat pulled apart so that the protrusions 71 can be displaced across the edges of the groove 73 up to the lateral groove 72. During assembly, the waist 74 is guided into the guide groove 75. Figure 33 shows a view, partly sliced through, of an inner element 5 and a ready- assembled locking member 17, here shown in its uninfluenced span, which causes certain pre-tensioning during introduction into the outer element. Figure 34 shows a view from above of details in accordance with Figure 33. In this position, the protrusions 72 are introduced into the lateral grooves 72. The locking member is thereby secured to the inner element 5 and cannot be disengaged from the same without the two ends of the locking member being pulled apart.

By the guide groove 75 fitting onto the waist 74, the one end of the locking member will be unaffected if the other end is pulled out or depressed. This arrangement provides a secure coupling of the locking

member 17 to the inner element, albeit that the assembly is easy to execute. The control buttons 10 can thereby be made as high and as large as desired without assembly being obstructed. The lateral grooves 72 are deeper than the protrusions 71, as shown in Figure 33. The spring 6 of the locking member 17 can thus be inflected inwards when the control buttons 10 are compressed in the direction of arrows C in accordance with Figure 35. The locking dowels 8 are thereby depressed towards the centre of the end 70 to such a position that the outer element 2 can be connected to the inner element 5 as previously described.

DESCRIPTION OF FURTHER EMBODIMENTS OF THE INVENTION The invention can further be varied within the scope of the innovative idea in accordance with the following description, where Figure 36 is a view from above of an inner element with an assembly groove; Figure 37 is a side view of the inner element in accordance with Figure 36; Figure 38 is a side view of a locking member; Figure 39 is a section A-A of the locking member in accordance with Figure 38; Figure 40 is a view from above of the locking member in accordance with Figure 38; Figure 41 is a view, partly sliced through, of an inner element in accordance with Figure 37 with a locking member in accordance with Figure 38 in a position of commenced assembly;

Figure 42 is a view, partly sliced through, of the device in accordance with Figure 41 with the locking member ready-assembled and in the locked position; Figure 43 is a view, partly sliced through, of the device in accordance with Figure 42 with the locking member in the open position; Figure 44 is a view from above of a further variation of an inner element; Figure 45 is a view from above of an inner element in accordance with Figure 44 with an assembled locking member; Figure 46 is a side view, sliced through, of the device in accordance with Figure 45, partially inserted into the outer element; Figure 47 shows the device in accordance with Figure 46, fully inserted into an outer element; Figure 48 shows a device in accordance with Figure 46 with a variation of the locking member; and Figure 49 shows a device where the locking member is mounted on an outer element.

Figures 36 to 43 describe a variation of a coupling in accordance with the invention that makes large control buttons possible, despite the locking member being inserted into a tube part 12 on an inner element 5. This enables a simple modification to such inner elements that are adapted to the existing type of standard coupling in that only a minor adjustment to the injection-moulding tool is necessary. Figure 36 shows a standard inner element 5 where the tube part 12 is provided

with axially directed guide grooves 20. The inner element has been provided with an assembly groove 80 for a separate locking member 17 in accordance with Figures 38-40. The locking member 17 is suitably manufactured of injection-moulded plastic and is provided with a spring 6 and with locking dowels 8 and control buttons 10 at both free ends of the spring 6. The control buttons 10 are connected to the locking member 17 by arms 9, which are laterally displaced so that they pass each other when the control buttons are compressed. This lateral displacement, illustrated in Figure 39, enables the arms to be so high that sufficient bending strength is achieved without assembly being obstructed. Figure 41 shows how the locking member 17 is introduced into the inner space 13 of the tube part 12 via the assembly groove 80.

The locking member is therefore assembled from the end on the inner element that faces away from the outer element in the connected position. Thus, the control buttons 10 do not have to pass through the tube part 12. The control buttons 10 are depressed towards each other, whereby the arms 9 proceed past each other. The locking dowels 8 thereby come so close to each other that assembly is possible. The control buttons 10 are not introduced into any space whatsoever and their size is therefore not limited by the assembly process. Figure 42 shows the locking member in its assembled position, somewhat compressed compared with its uninfluenced position in Figure 38. The locking dowels 8 are therefore pressed outwards through the guide grooves 20 with a certain pre-tensioning and are therefore able to lock into an outer element in like manner as in previously described embodiments. Figure 43 shows how the compression of the control buttons 10 in the direction of the forces F presses the locking dowels 8 down into the guide grooves 20, whereby an outer element can be disengaged in like manner as in previously described embodiments.

Figures 44-49 show variations on the invention where the locking dowels 8 are turned inwards. An inner element 5 in accordance with Figure 44 is provided with a tube part 12 comprising radially directed

guide grooves 20 for connection to an outer element. Furthermore, the inner element comprises a guide groove 80 and attachment grooves 81 for receiving a locking member 17. Figures 45 and 46 show the inner element 5 in accordance with Figure 44 with an assembled locking member 17. This locking member 17 is suitably manufactured of injection-moulded plastic and comprises locking dowels 8 that are turned inwards, towards each other, and that are inserted into the guide grooves 20. An outer element 2 can thereby be coupled with the inner element via radially directed locking grooves 3. Figure 46 shows such an outer element 2 with the tube part 12 partly inserted into it, in the unlocked position. Moreover, the locking member 17 comprises arms 9, which connect the locking dowels 8 with the locking member, and swivels 82, which in this embodiment are 4 in number. The swivels 82 are pivotably journalled in the attachment grooves 81. The locking member further comprises a V-shaped spring 6 and control buttons 10. Preferably, this locking member 17 has a smaller reach in its unassembled state so that a certain pre-tensioning is provided when it is assembled on the inner element. The locking member 17 is secured against lateral displacement by the guide groove 80. The fit into the guide groove is provided with some clearance, however. The arms 9 and the spring 6 can thereby move during manipulation.

Figure 47 shows the locking member in its influenced position.

Actuated by the compressing forces from the fingers of the operator in the direction of arrows F, the spring 6 is deformed and the arms 9 are turned by way of the journalling of the swivels 82 about their respective attachment grooves 81. The locking dowels 8 are thereby raised from their locked position and an outer element 2 can be slid onto or pulled off the tube part 12. Figure 47 shows an outer element arranged for coupling, with the locking grooves 3 aligned with the guide grooves 20. Actuated by the spring 6, via the arms 9, the locking dowels 8 will therefore be depressed through the locking grooves 3 and the guide grooves 20, when the control buttons 10 are released, thus providing a reliable but easily manipulated coupling. For more secure

operation, the swivels 82 can be snapped into the attachments grooves 81 or be secured in any other known way against outward displacement in the radial direction, for instance by replacing the swivels 82 of the locking member 17 and the attachment grooves 81 of the inner element 5 with holes for the fitting of shafts for the arms 9 to pivot about. Figure 48 shows a variation of the locking member 17, journalled in the inner element 5 in a way similar to that described above and with the same manipulation properties, but where the integrated spring 6 has been replaced by a separate spring element 83, for instance a helical spring, a laminated spring, or a rubber spring element. Two opposite locking members 17 with inwardly-turned locking dowels 8 are shown in the drawing, but it is also conceivable to use a single or several locking members 17 co-operating with a spring element, which can be separate or integrated with the locking member.

Figure 49 shows a variation with the same arrangement as previously with inwardly-turned locking dowels, but where the locking member is disposed on an outer element 2 with a tube part 84 comprising guide grooves 20. In the inner space 85 of the tube part 84, an inner element 5 with guide grooves 3 can be introduced and coupled to the outer element 2 by the operation of the locking dowels 8, which form part of locking members in accordance with one of the variations described above or in some other way that is obvious to those skilled in the art.

Figure 49 describes a design where the locking member is mounted on an outer element, which is connected to the tool part, but a similar arrangement where a locking member with inwardly-turned locking dowels is mounted on an outer element that is connected to the handle part is, of course, also conceivable.