WO1999050028A1

WO1999050028A1 - Screw driving element

Info

Publication number: WO1999050028A1
Application number: PCT/EP1999/001582
Authority: WO
Inventors: Daniel Gasser
Original assignee: Sfs Industrie Holding Ag
Priority date: 1998-03-31
Filing date: 1999-03-11
Publication date: 1999-10-07
Also published as: DE29805902U1; AU3330299A

Abstract

The invention relates to a screw driving element for receiving and holding a fixing head and for driving the same during a drilling and/or threading process and/or during the process of screwing in screws (2) which have a head (5). The diameter of the screw driving element is as large as or only slightly larger than the outer diameter (DA) of the threaded area of the screw (2). The screw driving element is provided with a rod-like tool (8) having an application element (10) for a inner application element (5) on a screw (2). In addition, the screw driving element is provided with a holding sleeve (9) which is arranged such that it can be displaced in relation to the rod-like tool (8). The opening (12) of the holding sleeve (9) has a diameter (DÖ) which is as large as or slightly larger than the diameter (DA) of the head (3) of a screw to be received, and is therefore as large as or slightly larger than the diameter of the threaded area (4) which is connected to the head (3). The axial depth of the opening (12) in the holding sleeve (9) is a multiple of the axial height (LK) of the head (3) of a screw (2) to be inserted or is a multiple of the thread pitch (S) of the threaded section (4) of a screw (2). The screw (2) can therefore be pushed into the opening (12) to a corresponding depth and engages with the wall of the opening (12) over the greater part of the entire displacement area. In addition, the shaft of the screw (2) is at least supported on the mouth edge of the opening (12) in order to prevent tilting of said screw.

Description

Screwdriver element

The invention relates to a screwdriver element for receiving and holding a fastener head and for driving the same during a drilling and / or thread forming process and / or during a screwing process of screws with a head whose diameter is the same size or only slightly larger than the outside diameter of the Thread area of the screw.

When screwing in such screws, which generally have a large length, problems arise, in particular when they are attached for the drilling or screwing-in process, because when a corresponding pressure is applied, a lack of a firm connection between the screwdriver element and the head of the screw causes tipping can be done. Already known in the construction are complex screwdriver elements, which a screw by e.g. Hold the spring-loaded jaws in a position aligned with the axis of rotation of the screwdriver element in order to facilitate the screwing-in process. Although such designs can meet the requirement for a corresponding axis alignment, they are normally too complex in terms of their structure and therefore also cost-intensive.

The present invention has therefore set itself the task of creating a screwdriver element of the type mentioned, with which even screws with a relatively long length can be properly set and at the same time achieve this with structurally simple means.

According to the invention this is achieved by a rod-like tool that can be brought into active connection with a hand-held device or a screwdriver with an attack for an internal attack on a screw and a holder sleeve that is displaceably arranged relative to the rod-like tool, the opening of which is equal in diameter or insignificantly larger than the diameter of the Head of a screw to be received and thus of the thread region adjoining the head, the axial depth of the opening in the holder sleeve having a multiple of the axial height of the head of a screw to be inserted or a multiple of the thread pitch of the threaded section of a screw, so that the screw accordingly can be inserted deeply into the opening and is operatively connected to the wall of the opening at least over a large part of the entire displacement area and Shank of the screw to prevent the same from tipping over at least at the mouth edge of the opening.

Already when inserting the screw into the screwdriver element there is a good holding of the same, because the screw can be inserted deep into the screwdriver element or the holder sleeve provided according to the invention, so that at least a part of the thread of the screw is received in the opening. This enables an at least approximate alignment of the axis of the screw and the axis of the screwdriver element. The screw can therefore no longer tip out when attaching or screwing in, even if there is no exactly suitable guide for the threaded area in the opening of the holder sleeve. By pushing the screw deep into the opening of the holder sleeve, the possible pivoting angle of the screw in the opening is practically reduced to zero. During a setting process, the holder sleeve comes to rest on the workpiece to be fastened before the screw is finally placed, the head still lying in the lowest position within the screwdriver element. When the screwdriver element is turned further, the holder sleeve can slide back on the rod-like tool, so that the screw is released more and more, but the attack of the tool is still engaged with the internal attack on the head of the screw and continues to come out of the screwdriver element, i.e. the holder sleeve leads out. The rod-like tool and the head of the screw remain in constant engagement with one another for torque transmission. This ensures that the screwdriver element remains in the necessary engagement with the head of the screw even in manual assembly until the screw is finally set.

Since the task according to the invention can be solved with very simple constructive means, namely with a rod-like tool and a holder sleeve that can be displaced on it, a corresponding robustness is guaranteed at the same time when used in the construction site. The simple structural measures not only achieve an optimum effect, but also create a screwdriver element which can be produced at relatively low costs.

An advantageous measure is seen in the fact that the axial depth of the opening in the holder sleeve has at least three to five times the axial height of the head or a thread pitch of the thread area of a screw to be inserted, the deeper the opening is, the better the mutual axis alignment between the screw and the screwdriver element is optimized. Of course, the displacement of the holder sleeve on the rod-like tool must also be adapted to the depth of the opening, so that the length of the holder sleeve and thus also the depth of the The opening must be restricted to a certain dimension in order not to cause the screwdriver element to be too long in the axial direction. Since the screw must be able to move easily in the opening of the holder sleeve both with the area of the head and with the thread area, a fit cannot be sought. For this reason, a correspondingly large axial depth of the opening is advantageous for optimal axis alignment.

A simple design provides that the holder sleeve is designed as a hollow cylinder with a bottom arranged at one end, the bottom having a through hole for slidably receiving the rod-like tool. In order to achieve proper guidance during the displacement process of the holder sleeve on the rod-like tool, care is naturally also taken to ensure that the bottom of the holder sleeve is made relatively thick when viewed in the axial direction. Tilting and thus jamming of the holder sleeve on the rod-like tool can thereby be reliably prevented. It does not matter whether you are talking about a holder sleeve with a bottom and a through opening or a continuous holder sleeve which has two sections of bores with different diameters - on the one hand for receiving the screw head and the corresponding threaded area and on the other hand for passing the rod-like Tool - has.

So that the holder sleeve remains in its rest position and is always returned to it, it is expedient if the holder sleeve is slidably held on the rod-like tool in a spring-loaded manner. In this context, it is advantageous if the holder sleeve is held by means of a helical spring in a position in which the attack of the rod-like tool lies in the deepest point within the opening in the holder sleeve. This ensures that the screwdriver element, ie the mutual position between the holder sleeve and the rod-like tool, is always in the starting position when starting with a screwing process, i.e. a screw is inserted into the screwdriver element. As soon as the freely projecting end of the holder sleeve stands up on the workpiece into which the screw is to be screwed, the holder sleeve is pushed back against the force of the coil spring along the rod-like tool without the mutual engagement between the rod-like tool and the internal attack on the screw is affected.

For proper functioning of the screwdriver element, it is proposed that the length of the displacement path between the rod-like tool and the holder sleeve be the same or greater than the depth of the opening in the holder sleeve. This ensures that the tool can remain in engagement with the screw in the area outside the holder sleeve, in order to leave open the possibility of being able to screw in the screw to such an extent that it is sunk relative to the surface of the workpiece. For this it is necessary that the attack at the free end of the rod-like tool can be carried out beyond the free end of the holder sleeve, i.e. the holder sleeve must be able to be pushed back by the appropriate amount on the rod-like tool.

So that the screwdriver element is not only protected in the area of the coil spring, but also in the area of the rotating parts thereof, and also cannot be mechanically damaged, the screwdriver element is supplemented by a tube piece that at least covers the area of the coil spring and can be firmly connected to the screwing device. A cover which coaxially surrounds the screwdriver element is thus present. However, such a piece of pipe can also be used as a depth stop, namely when it is adjustable on the screwing device in the axial direction and, if necessary, lockable.

So that all sensitive and also those areas that could lead to injuries in the event of manual intervention are safely covered, it is proposed that the holder sleeve also protrude at least with a portion of its axial length into the tube piece in the rest position of the same. Accordingly, only a corresponding area of the holder sleeve protrudes beyond the free end of the pipe section, so that the rear end of the holder sleeve always protrudes - even if only slightly - into the pipe section.

Since the pipe section only forms a kind of protective cover, no guidance is required between the pipe section and the holder sleeve. It is therefore proposed that the pipe piece coaxially encloses the holder sleeve with radial play.

In one embodiment of the screwdriver element it is provided that the holder sleeve at its freely projecting insert end both in the area of the inner wall and in the - 5 -

Area of the outer boundary is rounded or chamfered. This makes the screw easier to insert into the opening of the holder sleeve, since the rounding or chamfer forms a kind of insertion funnel. In addition, the rounding or chamfering on the outer boundary of the holder sleeve when placing the same on the workpiece is advantageous because after the placement no sharp edge is used, even if it is not screwed in at right angles to the surface of the workpiece.

Further features according to the invention and special advantages are explained in more detail in the following description with reference to the drawing. Show it:

1 shows a screwdriver element according to the invention, the holder sleeve provided here being shown in a longitudinal section;

Fig. 2 shows a screwdriver element inserted into a screwdriver, a pipe section that can be connected to the screwdriver additionally covering a partial area of the screwdriver element.

A screwdriver element 1 is concerned with receiving and holding a screw 2 during a drilling and / or thread forming process and / or during a screwing-in process of such a screw. The screwdriver element 1 provided for this purpose is specially designed for screws 2 with a head 3, the diameter of which is the same size or only slightly larger than the outer diameter DA of the threaded area 4 of the screw 2. Such a screw 2 also has an internal attack 5 in the head 3. The further configuration of the screw 2 with an additional thread area 6 and a drill tip 7 is irrelevant to the present invention. Any type of screw, including a screw without a drill tip 7 or instead of a drill tip 7 with a penetration tip, with a continuous thread, etc., can be used and processed with the screwdriver element according to the invention.

The screwdriver element 1 consists of a rod-like tool 8 and a holder sleeve 9. The rod-like tool 8 has at one end an attack 10 which can be used in the internal attack 5 of the screw 2. At the other end of the rod-like tool 8, an insertion pin 11 is provided, which is designed here as a hexagon. The insert bolt 1 1 is used for engagement and for torque transmission in cooperation with a screwing device. - 6 -

The holder sleeve 9 is displaceably arranged relative to the rod-like tool 8 and has an opening 1 2, the diameter DÖ of which is the same size or slightly larger than the diameter of the head 3 and thus of the threaded region 4 adjoining the head 3. The axial depth T of the Opening 1 2 in the holder sleeve 9 is a multiple of the axial height LK of the head 3 of the screw 2 to be used. Furthermore, the axial depth T can additionally or exclusively correspond to a multiple of the thread pitch S of the threaded section 4 of the screw 2.

The screw 2 can be inserted correspondingly deep into the opening 1 2 of the holder sleeve 9, so that not only the head 3 but also the threaded section 4 is in operative connection with the wall 1 3 of the opening 1 2 over a large part of the entire displacement range. Thus, the screw 2 can be supported at least at the mouth edge of the opening 1 2, so that the screw 2 is prevented from tilting when it is attached or screwed in.

The axial depth T of the opening 1 2 is at least three to five times the axial height LK of the head 3 or a thread pitch S of the thread area 4 of the screw 2 to be used. Of course, the length of the axial depth T can vary, i.e. in the case of a screw head which is relatively large in the axial direction, the corresponding multiple can be reduced. It is clear that when using a screw head with an axial length which is a multiple of the usual axial height LK, the dimensioning of the axial depth T can no longer be derived from a multiple of the axial height LK of the head. If necessary, even the simple height is sufficient, since the screw head already has a corresponding axial height. In the case of a corresponding multiple of the height of the screw head or the thread pitch, it is assumed that the screw head or thread pitch is usually used.

The holder sleeve 9 is designed as a hollow cylinder with a bottom 14 arranged at one end, the bottom having a through hole 15 for slidably receiving the rod-like tool 9. Here, however, one can also speak of a continuous holder sleeve 9, in which two sections of bores of different diameters are present, on the one hand for the opening 1 2 and on the other hand for the through hole 1 5.

The holder sleeve 9 is spring-loaded slidably on the rod-like tool 8, for which purpose a coil spring 16 is provided, which the rod-like Tool 8 coaxially encloses. The helical spring 16 has the effect that the holder sleeve 9 is always held in a rest position, as shown in FIGS. 1 and 2. In this rest position, the attack 10 of the rod-like tool 8 is in the lowest position within the opening 12. The helical spring 16 is inserted between two ring-shaped stop elements 17 and 18, the stop element 18 following the displacement movement of the holder sleeve 9. An O-ring 20 inserted into a groove 19 on the rod-like tool 8 is provided as a counter-holder and thus as a mutual securing of the position between the rod-like tool 8 and the holder sleeve 9.

In the rest position, the attack 10 should be arranged in the lowest position within the opening 12 of the holder sleeve 9. For a screwing operation until the end of the same, the attack 10 must, however, be able to be carried out into a position in which it projects beyond the free end of the holder sleeve 9. Therefore, the length LV of the displacement path between the rod-like tool 8 and the holder sleeve 9 is equal to or greater than the depth T of the opening 12 in the holder sleeve 9.

At its freely projecting insert end, the holder sleeve 9 - see FIGS. 1 and 2 - is rounded or chamfered both in the area of the inner wall and in the area of the outer boundary.

As can be seen in FIG. 2, a pipe piece 21 is additionally provided, which can be connected to corresponding elements 22 of a screwing device. In addition to assuming a covering effect, the pipe piece 21 can also be used as a depth stop if this can be connected in an axially adjustable and fixable manner.

Even in its foremost rest position, the holder sleeve 9 projects into the tubular piece 21 at least with a portion of its axial length. The holder sleeve 9 is coaxially enclosed by the pipe piece 21 with radial play. The pipe piece 21 does not have to assume any guiding properties, but only has to form a cover for the area of the screwdriver element in order to prevent access to the mutually displaceable elements and to the coil spring

The rod-like tool 8 is usually made of a special steel, whereas the holder sleeve 9 can consist of both metal and plastic. Needed of course it corresponding strength and also a corresponding abrasion resistance and rigidity of the holder sleeve 9.

The spring load between rod-like tool 8 and holder sleeve 9 is expediently provided in order to be able to return the holder sleeve 9 to the starting position again and again. If such a tool is always used in an approximately vertical direction, it is also conceivable that the holder sleeve 9 is returned to this position solely by its own weight. In this case, the coil spring 1 6 can be omitted. For a better function of the entire screwdriver element, the version with an integrated coil spring 1 6 is always preferred.

Claims

- 9 patent claims

1 . Screwdriver element for receiving and holding a fastener head and for driving it during a drilling and / or thread forming process and / or during a screwing process of screws with a head whose diameter is the same size or only slightly larger than the outside diameter of the threaded area of the screw, characterized by one with a handheld device or a screwdriver

Rod-like tool (8) which can be brought into an operative connection with an attack (10) for an internal attack (5) on a screw (2) and a holder sleeve (9) which is displaceable relative to the rod-like tool (8) and whose opening (1 2) has a diameter (DÖ) is the same size or slightly larger than the diameter (DA) of the head (3) of a screw (2) to be received and thus of the threaded area (4) adjoining the head (3), the axial depth (T) of the opening (1 2) in the holder sleeve (9) has a multiple of the axial height (LK) of the head (3) of a screw (2) to be used or a multiple of the thread pitch (S) of the threaded section (4) of a screw (2), so that the screw (2) can be inserted correspondingly deep into the opening (1 2) and at least over a large part of the entire displacement range with the

The wall (1 3) of the opening (1 2) is operatively connected and the shaft of the screw (2) can be supported at least at the mouth edge of the opening (12) to prevent it from tipping over.

2. Screwdriver element according to claim 1, characterized in that the axial depth (T) of the opening (12) in the holder sleeve (9) at least three to five times the axial

Height (LK) of the head (3) or a thread pitch (S) of the thread area (4) of a screw (2) to be inserted.

3. Screwdriver element according to claim 1 and / or 2, characterized in that the holder sleeve (9) is designed as a hollow cylinder with a bottom (14) arranged at one end, the bottom (14) having a through hole (1 5) for sliding

Inclusion of the rod-like tool (8).

4. Screwdriver element according to claims 1 to 3, characterized in that the holder sleeve (9) is held spring-loaded displaceably on the rod-like tool (8). - 10 -

5. Screwdriver element according to claim 4, characterized in that the holder sleeve (9) is held by means of a helical spring (16) in a position in which the attack (10) of the rod-like tool (8) in the deepest point within the opening (12 ) lies in the holder sleeve (9).

6. Screwdriver element according to claims 1 to 5, characterized in that the

Length (LV) of the displacement path between the rod-like tool (8) and the holder sleeve (9) is equal to or greater than the depth (T) of the opening (12) in the holder sleeve (9).

7. Screwdriver element according to claims 1 to 6, characterized by an at least the area of the coil spring (16) covering, firmly connectable to the screwdriver pipe piece (21).

8. Screwdriver element according to claim 7, characterized in that the holder sleeve (9) protrudes into the tubular piece (21) at least with a portion of its axial length even in the rest position thereof.

9. screwdriver element according to claims 7 and 8, characterized in that the

Pipe piece (21) coaxially surrounds the holder sleeve (9) with radial play.

10. Screwdriver element according to one of claims 1 to 9, characterized in that the holder sleeve (9) is rounded or chamfered at its freely projecting insert end both in the region of the inner wall and in the region of the outer boundary.