Wood screw made of metal, method for producing a wood screw, and device for producing a wood screw

Abstract

The invention relates to a wood screw made of metal, comprising a screw shank and a screw head, wherein: the screw shank is provided at least partly with a thread for screwing into workpieces made of wood or wooden material, in particular solid wood, and the screw head is provided with a drive formation; the screw shank and the screw head are formed in one piece; and a contact washer, which is non-detachably connected to the screw head and / or the screw shank and is in the form of a part separate from the screw shank and screw head, is provided.

Description

[0001] Metal wood screw, method for manufacturing a wood screw and device for manufacturing a wood screw

[0002] The invention relates to a metal wood screw comprising a shank and a head, wherein the shank is at least partially threaded for screwing into workpieces made of wood or wood-based materials, in particular solid wood, and the head is provided with a drive mechanism, the shank and head being formed in one piece. The invention also relates to a method for manufacturing a wood screw and a device for manufacturing a wood screw.

[0003] When joining wooden workpieces or fastening workpieces made of other wood materials to a second wooden workpiece, a screw with a large bearing surface on the underside of the head is advantageous. For example, the material on which the underside of the screw head rests may be soft, allowing a large screw head to transmit higher axial forces. In other words, the resistance to the screw head being pulled out is increased. A large screw head is particularly beneficial when fastening soft insulation materials to a wooden facade or beams. Furthermore, a large screw head is advantageous when the workpiece on which the underside of the screw head rests is made of a brittle material.In this case, a screw head with a large surface area on the underside can minimize the occurrence of local stress maxima, so that in this case too the resistance of the connection to a pull-through of the screw head is increased.

[0004] It is common practice to use screws with washers, backing washers, or guide washers. Handling such guide washers can be difficult, or at least time-consuming, as care must be taken during tightening to ensure that the washer does not slip off the screw shank or become jammed against it.

[0005] The invention aims to provide an easy-to-use screw that can provide a large contact surface.

[0006] According to the invention, a metal wood screw with the features of claim 1, a method for manufacturing a wood screw with the features of claim 9, and a device for manufacturing a wood screw with the features of claim 14 are provided. Advantageous embodiments of the invention are specified in the dependent claims. A metal wood screw according to the invention has a screw shank and a screw head, wherein the screw shank is provided at least partially with a thread for screwing into workpieces made of wood or wood-based material, in particular solid wood, and wherein the screw head is provided with a drive element, wherein the screw shank and the screw head are formed in one piece, and wherein a washer is provided which is permanently connected to the screw head and / or the screw shank and is designed as a separate part from the screw shank and screw head.

[0007] A separate washer, permanently attached to the screw head and / or shank, enables the production of a simple wood screw with a large contact surface on a workpiece. In particular, the screw head does not need to be shaped using large amounts of material from a blank to create a large contact surface on its underside; instead, this large contact surface is at least partially provided by the washer. Since the washer is permanently attached to the screw head and / or shank, the wood screw according to the invention is very easy to handle, as the washer is captive and permanently fixed to the screw head and / or shank. According to the invention, the washer can be fixed to the screw head and / or shank in a rotationally fixed manner or be rotatable relative to the screw head and / or shank.

[0008] In a further development of the invention, the mounting washer is positively connected to the screw head and the material of the screw head extends in a radial direction at least on the top side of the mounting washer beyond the central opening of the mounting washer, wherein, when forming the screw head by means of cold forming, the material of the screw head is displaced in a radial direction beyond the central opening of the mounting washer at least on the top side of the mounting washer.

[0009] In the wood screw according to the invention, two components, in this case the washer and the screw blank, are positively connected. Typically, the head geometry of a screw is produced using forming processes, such as upsetting or extrusion, in two or more forming operations. The achievable head diameters are limited by the formability of the screw material. According to the invention, the head diameter is increased by joining two components. The washer is inserted into the screw's manufacturing sequence between the forming operations. During a forming operation, the washer is positively connected to the screw head while the screw head is simultaneously shaped. This shaping can, for example, involve pressing in a drive element or pressing out another shape on the screw head.Since the screw head is formed while the edge of the central opening of the mounting washer surrounds the screw head blank, the mounting washer, and in particular its central opening, functions as part of the tool, for example a die, which influences the material flow during the forming of the screw head. According to the invention, no separate joining operations take place; rather, the joining is part of an existing manufacturing sequence. After the mounting washer is positively connected to the screw head, the mounting washer can be either rotationally fixed or rotatable relative to the screw head.

[0010] In a further development of the invention, the material of the screw head extends radially beyond the central opening of the mounting disc on both a top and a bottom surface, with the material displacement being effected in particular by cold forming when shaping the screw head.

[0011] The washer is thus positively engaged in two opposite directions, parallel to the screw shank, and held in the screw head. A circumferential bead or several projections, which bear against one underside of the washer, can also be formed on the blank before the screw head is formed. This ensures that the washer is securely held on the screw head.

[0012] In a further development of the invention, a connection between the screw head and the washer is designed with respect to the rotatability of the washer and the screw head about the central longitudinal axis of the screw shank such that, when the wood screw is screwed into the workpiece, the washer rests with its underside against a workpiece and the underside is pressed against the surface of the workpiece, the screw head can rotate relative to the washer.

[0013] In this way, a very large contact area can be achieved, but on the other hand, once the underside of the washer rests on the workpiece, the torque for further screw tightening does not increase as much as with a washer rigidly connected to the screw head. This is because the screw head can rotate within the central opening of the washer. Consequently, the underside of the washer does not rotate on the workpiece surface but remains stationary. Only the screw head, and therefore also the screw shank, continues to rotate relative to the workpiece, thus further increasing the clamping force with which the underside of the screw head and the contact surface of the washer act on the workpiece surface.Even when unscrewing the screw according to the invention, the required torque is lower than if the contact washer were permanently connected to the screw head.

[0014] In a further development of the invention, a section of the screw head is pressed into the central opening of the mounting disc.

[0015] In this way, a screw can be pressed onto a washer without loss or captivity. The washer is thus precisely positioned and permanently connected to the screw head and / or shank. For example, the washer can be pressed onto the screw head before a thread is rolled onto the shank.

[0016] In a further development of the invention, the section of the screw head that is pressed into the central opening has radially projecting projections or ribs.

[0017] These ribs run parallel to the screw shank, but can also curve in a spiral shape relative to the shank. When the screw head is pressed into the central opening, the ribs penetrate the wall of the central opening in the washer, thus ensuring a reliable hold between the screw head and the washer.

[0018] According to the invention, the projections or ribs are primarily not intended for transmitting torque from the screw head to the contact washer, but for securing the contact washer to the screw head without play.

[0019] In a further development of the invention, a press fit between the screw head and the washer is designed and / or the radially projecting projections are designed such that when the wood screw is screwed into the workpiece, the washer rests with its underside against a workpiece and the underside is pressed against the surface of the workpiece, the screw head can rotate relative to the washer.

[0020] In this way, the press fit between the screw head and the washer can loosen if the underside of the washer rests on a workpiece surface and the static friction between the underside of the washer and the workpiece surface exerts a greater circumferential force than the press fit between the screw head and washer can withstand. This allows the screw head to rotate relative to the washer when the screw is tightened, preventing the tightening torque from increasing excessively after the washer's contact surface rests on the workpiece.

[0021] In a further development of the invention, a circumferential bead is formed on the screw shank or screw head and / or individual projections on the screw shank or screw head are designed such that an outer diameter of the screw shank or screw head in the area of ​​the bead or projections is at least partially larger than an inner diameter of the central opening of the contact washer, so that the contact washer is held captive on the screw head and / or screw shank.

[0022] Such a circumferential bead and / or individual projections on the screw shank or screw head can be formed by rolling, pinching, or another forming manufacturing process. The circumferential bead and / or the individual projections ensure that the washer is captive on the screw shank or screw head. If the circumferential bead is located on the screw shank, the washer is secured towards the screw head by the underside of the screw head and towards the screw tip by the circumferential bead and / or the individual projections.

[0023] In the method according to the invention, the pressing of the mounting washer with the screw head during the forming of the screw head is provided, thereby creating a positive fit between the screw head and the mounting washer.

[0024] In this way, the washer and screw head can be joined during a forming operation on the screw head. Compared to the production of a conventional wood screw, no further or additional forming operations are required. During such a forming operation, the inner circumference of the washer's central opening then becomes part of the tool, for example, part of a die.

[0025] In a further development of the invention, a section of the screw head is pressed into a through-opening of the mounting disc.

[0026] In a further development of the invention, a central opening of the mounting disc forms part of a die for shaping the screw head.

[0027] In a further development of the invention, the formation of a circumferential bead and / or individual projections on the screw shank or screw head is provided for axially holding the mounting disc, so that an outer diameter of the screw shank or screw head in the area of ​​the bead and / or projections is at least partially larger than an inner diameter of a through-hole in the mounting disc.

[0028] In a further method according to the invention for producing a wood screw according to the invention, the screw head is pressed section by section into a central opening of the mounting washer, thereby creating an interference fit between the screw head and the mounting washer.

[0029] In a device for manufacturing a wood screw according to the invention, a central opening of the mounting disc forms part of a die for shaping the screw head.

[0030] Further features and advantages of the invention will become apparent from the claims and the following description of preferred embodiments of the invention in conjunction with the drawings. Individual features of the different illustrated and / or described embodiments can be combined in any way without departing from the scope of the invention. In particular, individual features of the different illustrated and / or described embodiments can be combined with individual features of other embodiments without exceeding the scope of the invention. The drawings show:

[0031] Fig. 1 shows a sectional view of a first embodiment of a wood screw according to the invention.

[0032] Fig. 2 shows a cylindrical blank for manufacturing the wood screw of Fig. 1,

[0033] Fig. 3 shows the blank of Fig. 2 after a first forming operation,

[0034] Fig. 4 shows a representation of the blank from Fig. 3 and a sectional view of a

[0035] Mounting disc before placing the mounting disc on the blank of Fig. 3,

[0036] Fig. 5 shows a schematic sectional view of a wood screw according to a second embodiment of the invention.

[0037] Fig. 6 shows a blank for manufacturing the wood screw of Fig. 5 before forming a thread and a screw tip; Fig. 7 shows a top view of the blank of Fig. 6 before sliding on the washer.

[0038] Fig. 8 shows a view of the section plane AA of the blank in Fig. 7.

[0039] Fig. 9 shows a top view of the mounting disc,

[0040] Fig. 10 shows a top view of a wood screw according to a third embodiment of the invention,

[0041] Fig. 11 shows a view of the section plane CC in Fig. 10, where the section view is schematic.

[0042] Fig. 12 shows a side view of a blank for manufacturing the wood screw of Fig. 10.

[0043] Fig. 13 shows a top view of the blank 88 shown in Fig. 12.

[0044] Fig. 14 shows a view of the section plane AA in Fig. 13.

[0045] Fig. 15 shows a top view of the mounting disk 82 and

[0046] Fig. 16 shows a view of the section plane BB in Fig. 15.

[0047] Fig. 1 shows a schematic sectional view of a wood screw 10 according to the invention. The wood screw 10 is made of metal and has a screw shank 12 and a screw head 14. The screw head 14 has a larger diameter than the approximately cylindrical screw shank 12. A thread 14 is provided, at least partially, on the screw shank 12, which is designed for screwing into workpieces made of wood or wood-based materials, in particular solid wood. The design of a thread for screwing into workpieces made of wood or wood-based materials, as opposed to a thread for screwing into workpieces made of metal, plastic, or other materials, is known to those skilled in the art and will not be explained further.

[0048] The screw shank 12 terminates at a schematically depicted screw tip 18, the diameter of which gradually tapers to a point-like end in the region of the tip 18. The thread 16 extends to the area of ​​the screw tip 18, and, as is typical for a thread used in wood, the thread flank height decreases along the screw tip and towards the point-like end of the screw tip 18. According to the invention, the wood screw 10 can also be provided with a drill tip.

[0049] The screw head 14 is provided with a drive element 20, which in the illustrated embodiment is designed as an internal polygon. The specific design of the drive element 20 is not relevant to the invention. For example, the drive element 20 can also be star-shaped, internal hexagonal, external hexagonal, or in some other way.

[0050] As can be seen in Fig. 1, the wood screw 10 is provided with a washer 22, which is positively locked to the screw head 20. The screw head extends radially beyond a central opening in the washer 22 on the upper surface of the washer 22 (shown at the top in Fig. 1). Thus, in Fig. 1, the washer 22 is positively locked against upward movement by the screw head 14.

[0051] In the opposite direction, the underside of the screw head also extends radially beyond the central opening of the washer 22. Thus, in Fig. 1, the washer 22 is also positively locked to the screw head 14 in a downward direction.

[0052] An interference fit exists between the edge of the central opening of the washer 22 and the screw head 14, so that the washer 22 is rotationally fixed to the screw head 14 against typical torques. Alternatively, there may be no interference fit, in which case the washer 22 is rotatably fixed to the screw head 14.

[0053] A special feature of the wood screw 10 according to the invention is that the bearing washer 22 is press-fitted to the screw head 14 during its formation. The bearing washer is placed on a blank for the production of the wood screw 10 (see Fig. 4), and then the top surface of the screw head 14 with the drive element 20 is formed by means of a forming operation. During this forming operation, the material of the blank flows into the shape shown in Fig. 1, in other words, in a radial direction beyond the central opening of the bearing washer 22.

[0054] The wood screw 10 according to the invention can thus be manufactured without additional forming operations, compared to a conventional wood screw, wherein the washer 22 is positively connected to the screw head 14 by means of a press fit.

[0055] Within the scope of the invention, the mounting disc 22 can also be positively connected to the screw shaft 12 during a forming operation of the screw shaft 12, for example in such a way that the screw shaft 12 is sectionally compressed and thus thickened and in this way a press fit with the central opening of the mounting disc 22 is achieved.

[0056] In the manufacture of the wood screw 10 according to the invention, the screw head 14 is first formed and at the same time the washer 22 is positively connected to the screw head 14, as explained above, and only then is the thread 16 rolled onto the screw shank 12 and the screw tip 18 formed.

[0057] Fig. 2 shows a cylindrical blank 30 for manufacturing the wood screw 10 according to the invention of Fig. 1, wherein the contact washer 22 is not shown in Fig. 2.

[0058] Fig. 3 shows the blank 30 after a first forming operation. Only in the lower section is the blank 30 still cylindrical and has the same diameter as in the state of Fig. 2. To produce the screw head, a section of the cylindrical blank 30 of Fig. 2 was formed such that a contact bead 32 and a cylindrical body 34 above the contact bead 32 with a slightly smaller diameter than the contact bead 32 are formed.

[0059] The outer diameter of the body 34, as shown in Fig. 4, is matched to the inner diameter of the central opening of the contact disc 22, so that the central opening of the contact disc 22 can be slid onto the body 34 until it is stopped by the contact bead 32 and then rests on the contact bead 32. The diameter of the central opening of the contact disc 22 is therefore slightly larger than the diameter of the body 34 and smaller than the outer diameter of the contact bead 32.

[0060] As previously explained, when the contact disc 22 rests on the contact bead 32 of the blank 30 (Figs. 3 and 4), the screw head 14 with the drive element 20 is formed, for example, by pressing a punch into the blank 30 from above. The material of the body 34 of the blank 30 then flows radially outwards and is simultaneously pressed downwards, forming both the drive element 20 and the radially extending edge of the screw head 14 (see Fig. 1). As described, the contact disc 22 can thus be positively connected to the screw head 14 during a forming operation that creates the drive element 20 and the screw head 14. During the forming operation, the contact disc 22 forms part of the tool that limits and guides the flow of the material from the blank 30.

[0061] The press fit between the screw head 14 and the washer 22 is designed such that the washer 22 is attached to the screw head 14 without play and cannot be lost. Even when a contact surface of the washer 22 (located at the bottom in Fig. 1) is pressed against a workpiece surface, the screw head 14 cannot rotate relative to the washer 22. Alternatively, the washer 22 is rotatable relative to the screw head 14.

[0062] Fig. 5 shows a sectional view of a wood screw 50 according to a further embodiment of the invention. The wood screw 50 has a screw head 54 with the drive element 20 and a screw shank 52 with a thread 56 for screwing into wood or wood-based material. The screw shank 52 is provided with a tip 58. The thread 56 and the screw tip 58 are designed in the same way as the thread 16 and the screw tip 18 of the wood screw 10 of Fig. 1 and are therefore not described again. A washer 22 is positively connected to the screw head 54. Upward movement of the washer 22 in Fig. 5 is prevented by the edge of the screw head 54, which extends radially beyond the central opening of the washer 22.

[0063] A downward movement of the mounting washer 22, as shown in Fig. 5, is prevented by a circumferential bead 60, which is rolled onto the screw shank 52 below the mounting washer 22 and extends radially beyond the central opening of the mounting washer 22. According to the invention, the circumferential bead can also form part of the screw head and, for example, be arranged at the transition from the screw head to the screw shank.

[0064] Towards the tip 58, below the circumferential bead 60, another circumferential bead 62 is formed during the formation of the bead 60. The bead 60 is created by pressing a circumferential notch into the screw blank and is a manufacturing process. The material is thereby displaced from the notch between the two circumferential bead 60 and 62 both upwards and downwards, resulting in the circumferential bead 60 and the circumferential bead 62. According to the invention, the bead 62 can be omitted, for example, by using a different manufacturing process for producing the bead 60. The washer 22 is thus captive and securely attached to the screw head 54 of the wood screw 50.In the circumferential direction, the connection between the washer 22 and the screw head 54 can be designed such that the washer 22 can rotate relative to the screw head 54, at least when the underside of the washer 22 is already pressed against a workpiece surface. Alternatively, the connection is designed such that the washer 22 is rotationally fixed to the screw head 54.

[0065] Fig. 6 shows a blank 64 for manufacturing the wood screw 50 of Fig. 5. The washer 22 is already connected to the fully formed screw head 54. The screw shank 52, however, is still cylindrical, and starting from the state shown in Fig. 6, the thread 56 and the screw tip 58 are formed by rolling until the wood screw 50 of Fig. 5 is completed.

[0066] Fig. 7 shows a blank 70 for the production of the screws 50 according to the invention in a top view. The fully formed upper surface of the screw head 54 and the also fully formed drive element 20 are visible.

[0067] Fig. 8 shows a view of the section plane AA in Fig. 8.

[0068] It can be seen that the blank 70 below the finished top of the screw head 54 has a cylindrical section 72 with a first, larger diameter, followed on the blank 70 by a second cylindrical section 74 with a smaller diameter, which on the finished wood screw 50 forms the screw shaft 52 with the thread 56 and the tip 58.

[0069] To manufacture the wood screw 50, the mounting washer 22 shown in Fig. 9 is pushed onto the blank 70 shown in Fig. 8 from below until the central opening of the mounting washer 22 rests against an underside of the finished upper surface of the screw head 54. The central opening is thus located at the upper end of the cylindrical section 72 of the blank 70.

[0070] Subsequently, as explained with reference to Fig. 5, the two circumferential ridges 60, 62 are formed on the cylindrical section 72 of the blank 70 in order to then hold the contact disc 22 positively on the screw head 54.

[0071] Of course, within the scope of the invention, only the circumferential bead 60 can be formed without the circumferential bead 62. Alternatively or additionally, individual projections extending radially beyond the central opening of the mounting disc 22 can be formed in the section 72 of the blank 70 to secure the mounting disc 22 positively to the screw head 54. Such individual projections can be formed by rolling, but also, for example, by pinching.

[0072] Fig. 10 shows a wood screw 80 according to a third embodiment of the invention in a top view. The upper side of the screw head 84 with the drive element 20 can be seen in Fig. 10. A washer 82 is connected to the screw head 84.

[0073] Fig. 11 shows a view of the section plane CC in Fig. 10.

[0074] It can be seen that the screw head 84 is designed as a countersunk head and that a screw shank 92 adjoins the screw head 84, which is provided with a thread 96 and a screw point 98. The thread 96 and the screw point 98 are designed in the same way as the thread 16 and the screw point 18 of the wood screw 10 in Fig. 1, which have already been explained with reference to Fig. 1, and are therefore not explained again.

[0075] The screw head 84 is flush with its upper surface against the upper surface of the mounting washer 82. The mounting washer 82 has, as shown in Fig. 16, a central opening which tapers from its upper surface into a frustoconical shape and then becomes cylindrical from approximately half the thickness of the mounting washer to its end. The underside of the screw head 84 is shaped accordingly. Consequently, the screw head 84 tapers from its upper surface into a frustoconical shape and then continues in a frustoconical shape to a length corresponding to the thickness of the mounting washer 82.

[0076] The underside of the screw head 84 is pressed into the central opening of the mounting washer 82, creating an interference fit between the cylindrical sections of the screw head 84 and the central opening of the mounting washer 82. To ensure an interference fit, several radially projecting projections 86 are provided on the cylindrical section adjoining the frustoconically tapered section of the screw head 84 (see Fig. 12). The projections 86 are evenly distributed around the circumference of the cylindrical section of the underside of the screw head 84 and extend parallel to the central longitudinal axis 100 of the blank shown in Fig. 12 or the screw shank 92 (see Fig. 11).

[0077] When the screw head 84 is pressed into the central opening of the support washer 82, the projections 86 penetrate a short distance into the wall of the central opening of the support washer 82 in its cylindrical section and thereby ensure a reliable press fit of the screw head 84 in the central opening of the support washer 82.

[0078] The projections 86 can be designed, or the diameter of the central opening of the mounting washer 82 in its cylindrical section can be designed, such that after exceeding a predefined torque between the mounting washer 82 and the screw head 84, the projections 86 either shear off and / or the projections 86 can move relative to the then enlarged central opening of the mounting washer 82. This allows the screw head 84 to be rotated relative to the mounting washer 82 when the underside of the mounting washer 82 is already pressed against a workpiece surface and the wood screw 80 is still to be driven further into the workpiece.

[0079] Fig. 12 shows a side view of the blank 88 for manufacturing the wood screw 80 according to the invention. The projections 86 running parallel to the central longitudinal axis 100 on the cylindrical section of the outside of the screw head 84 are clearly visible.

[0080] Fig. 13 shows a top view of the blank 88 of Fig. 12. The drive element 20, already formed on the blank, can be seen.

[0081] Fig. 14 shows a view of the section plane AA in Fig. 13. The section plane runs between two projections 86, compare Fig. 12.

[0082] Fig. 15 shows a top view of the mounting disc 82. It can be seen that the central opening of the mounting disc 82 initially has a frustoconical tapering section, which, as shown in Fig. 16, has a cone angle of 90° and then transitions into a cylindrical section until the end of the central opening on the underside of the mounting disc 82.

[0083] When the blank 88 is pressed into the central opening of the mounting disc 82, the projections 86 penetrate the circumferential wall of the cylindrical section of the mounting disc 82, thereby ensuring a reliable press fit of the blank 88 in the central opening of the mounting disc 82. After the blank 88 has been pressed into the mounting disc 82, the thread 96 and the screw tip 98 are rolled onto the cylindrical section of the blank 88 below the screw head 84.

Claims

Patent claims 1. Metal wood screw with a screw shank and a screw head, wherein the screw shank is at least partially provided with a thread for screwing into workpieces made of wood or wood-based material, in particular solid wood, and the screw head is provided with a drive feature, wherein the screw shank and the screw head are formed in one piece, characterized in that a washer is provided which is inseparably connected to the screw head and / or the screw shank and which is designed as a separate part from the screw shank and screw head.

2. Wood screw according to claim 1, characterized in that the washer is positively connected to the screw head and the material of the screw head extends radially beyond the central opening of the washer at least on the top side of the washer, wherein, when forming the screw head by means of cold forming, the material of the screw head is displaced radially beyond the central opening of the washer at least on the top side of the washer.

3. Wood screw according to claim 2, characterized in that the material of the screw head extends radially beyond the central opening of the mounting washer on both a top and a bottom surface, wherein in particular the material displacement is effected by cold forming when forming the screw head.

4. Wood screw according to claim 1, 2 or 3, characterized in that a connection between screw head and washer is designed with respect to a rotatability of washer and screw head about the central longitudinal axis of the screw shank such that when the wood screw is screwed into the workpiece, the washer rests with its underside against a workpiece and the underside is pressed against the surface of the workpiece, the screw head can rotate relative to the washer.

5. Wood screw according to one of the preceding claims, characterized in that a section of the screw head is pressed into the central opening of the mounting washer.

6. Wood screw according to claim 5, characterized in that the section of the screw head which is pressed into the central opening has radially projecting projections or ribs.

7. Wood screw according to claim 5 or 6, characterized in that a press fit between screw head and washer is formed and / or the radially projecting projections are formed such that when the wood screw is screwed into the workpiece, the washer rests with its underside against a workpiece and the underside is pressed against the surface of the workpiece, the screw head cannot rotate relative to the washer.

8. Wood screw according to one of the preceding claims, characterized in that a circumferential bead is formed on the screw shank or on the screw head and / or individual projections are formed on the screw shank or on the screw head, such that an outer diameter of the screw shank or the screw head in the area of ​​the bead or the projections is at least partially larger than an inner diameter of the central opening of the bearing washer, so that the bearing washer is captive on the screw head and / or on the screw shank.

9. Method for manufacturing a wood screw according to one of the preceding claims, characterized by pressing the bearing washer with the screw head during the forming of the screw head and thereby creating a positive fit between the screw head and the bearing washer.

10. Method according to claim 9, characterized by pressing a section of the screw head into a through-opening of the mounting disc.

11. Method according to claim 9 or 10, wherein a central opening of the mounting disc forms part of a die for shaping the screw head.

12. Method according to claim 9, 10 or 11, characterized by forming a circumferential bead and / or individual projections on the screw shank or screw head for axially holding the mounting disc, such that an outer diameter of the screw shank or screw head in the area of ​​the bead and / or projections is at least sectionally larger than an inner diameter of a through-hole in the mounting disc.

13. Method for manufacturing a wood screw according to any one of the preceding claims 1 to 8, characterized by pressing the screw head section by section into a central opening of the mounting washer and thereby creating an interference fit between the screw head and the mounting washer.

14. Device for manufacturing a wood screw according to one of the preceding claims, wherein a central opening of the mounting disc forms part of a die for shaping the screw head.

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