Device for guiding tools on a workpiece parallel to a workpiece edge

Abstract

Device for guiding tools (14) on a workpiece (11) parallel to a workpiece edge (18), comprising: • a guide rail (12) along which the tool (14) can be moved linearly, • a one-piece or multi-piece spacer, • a one-piece or multi-piece workpiece stop, • a one-piece or multi-piece coupling element for detachably connecting the spacer to the guide rail (12), characterized in that the workpiece stop is attached to the spacer and is guided exactly parallel to the longitudinal axis of the guide rail (12) and can be fixed at selectable intervals between the workpiece edge (18) and the longitudinal axis of the guide rail (12).

Description

[0001] The present invention lies in the technical field of woodworking tools. Generic woodworking tools are shown in DE 20 2022 107 096 U1, US 2020 / 0 215 713 A1, US 2014 / 0 026 725 A1 and DE 10 2019 131 527 A1 and can also be seen at https: / / www.youtube.com / watch?v=3ZNiUh0dHP0.

[0002] Among other things, when cutting or formatting larger workpieces, especially wood-based panels, it becomes impractical or unwieldy to use a panel saw, for example, beyond a certain size. This involves guiding the panel over the tool. A stationary panel saw, where the saw unit moves perpendicularly across the panel, is not always available or may not be cost-effective to purchase if large panels only need to be cut occasionally. This is particularly relevant for hobby woodworkers with limited budgets and workshop space. A similar problem arises when other tools are to be used in the same way, for example, when routing grooves parallel to a workpiece edge.

[0003] An alternative is to guide the saw unit along a guide rail placed on the workpiece. Parallel fences are commonly available for this purpose; these are attached to standard guide rails. These parallel fences typically consist of two adjustable rails, each with a workpiece stop attached to one side and the other side to the guide rail. Two of these adjustable rails are always used to align the guide rail parallel to a side or edge of the workpiece. For a parallel cut, the workpiece stops must be aligned along the adjustable rails to the same distance from the guide rail. A length scale on both adjustable rails is usually used for this purpose.A disadvantage of these parallel stops is that strict parallelism cannot be truly achieved, as reading errors can always occur when aligning the two workpiece stops on the adjustment rails. Furthermore, inaccuracies can arise because the mounting of the parallel stop's adjustment rails to the guide rail is not precisely centered on the edge of the guide rail's long side. This is because a groove in the guide rail is typically used for this purpose, and the mounting in this groove is often not self-centering. Another disadvantage is that the often quite long rails of the parallel stop require a complex mounting process, making handling more difficult, as quick attachment or removal of the parallel stop from the guide rail is not possible.

[0004] The present invention is therefore based on the objective of providing a device that offers higher precision and allows a strictly parallel alignment of a guide rail to a workpiece edge while simultaneously simplifying handling.

[0005] The problem is solved according to the invention in the form of a first solution by a device having the features listed in claim 1, i.e. by a: Device for guiding tools (14) on a workpiece (11) parallel to a workpiece edge (18), comprising: • a guide rail (12) along which the tool (14) can be moved linearly, • a one-piece or multi-piece spacer, • a one-piece or multi-piece workpiece stop, • a one-piece or multi-piece coupling element for detachably connecting the spacer to the guide rail (12), characterized in that the workpiece stop is attached to the spacer and is guided exactly parallel to the longitudinal axis of the guide rail (12) and can be fixed at selectable intervals between the workpiece edge (18) and the longitudinal axis of the guide rail (12).

[0006] The problem is also solved by a method of claim 9. An embodiment of the invention is described below with reference to the Fig. 1 to 3 explained. Fig. Figure 1 shows a top view of an adjustment rail (1a) with an elongated hole (2) and a connecting element (3a) attached to the end face of the adjustment rail (1a). It also shows a stop (4a) attached below the adjustment rail (1a) with two positioning pins (5) and two positioning holes (6). The stop (4a) is movable along the direction of movement (10) and can be fastened to the adjustment rail (1a) with a knurled screw (7). Fig. Figure 2 shows a top view of a workpiece (11) with a guide rail (12) placed on it, a cutting line (19), and a saw (14) movable along the guide rail (12) in the cutting direction (15). Two magnets (13a and 13b) are also shown, which are slidably mounted in a groove (17) of the guide rail (12) and can be fixed in selectable positions along the groove. Adjustable rails (1a and 1b) with magnetic connecting elements (3a and 3b) are detachably connected to each magnet (13a and 13b). Two stop guides (4a and 4b) are also shown, which rest against the workpiece edge (18) and are each fixed to the adjustable rails (1a and 1b). A cutting width (16) is also indicated, defined by the distance between the workpiece edge (18) and the cutting line (19).In this case, the cutting line corresponds to the outer longitudinal edge of the guide rail (12) along which the saw blade of the saw (14) is guided. Fig. Figure 3 shows a top view of two stop riders (4a and 4b) attached to the adjustment rails (1a and 1b), which are connected to each other by the positioning pins (5) of the stop rider (4b) engaging in the positioning bores (6) of the stop rider (4a). The two connecting elements (3a and 3b), which have the same width as the stop riders (4a and 4b), also touch each other.

[0007] In this embodiment, the device is formed from two adjustable rails (1a and 1b) with their respective connecting elements (3a and 3b), two magnets (13a and 13b), two stop lugs (4a and 4b), and the guide rail (12). The two adjustable rails (1a and 1b) form a spacer, the two stop lugs (4a and 4b) form a workpiece stop, and the connecting elements (3a and 3b) together with the magnets (13a and 13b) form a coupling element.

[0008] The device can be operated as follows: First, the desired machining width or cutting width (16) is marked on the workpiece (11). Starting from the workpiece edge (18), a mark is made on the workpiece (11) at the desired cutting width (16) using a suitable measuring tool, e.g., a tape measure. The guide rail (12) with the cutting line (19) is then aligned with this mark. Initially, it is irrelevant whether a workpiece edge (18) on the left (as shown) or right side of the guide rail is selected.

[0009] Next, the two knurled screws (7) are loosened, and the two stop riders (4a and 4b) are positioned outside the workpiece (11) and beyond the workpiece edge (18), respectively. They are then connected by engaging the positioning pins (5) of stop rider (4a) in the positioning holes (6) of stop rider (4b). The two stop riders (4a and 4b) and the two connecting elements (3a and 3b), which have the same width as the stop riders (4a and 4b), then touch, and the adjustment rails (1a and 1b) align parallel to each other. The magnets (13a and 13b) are then moved in the groove (17) of the guide rail (12) to approximately the height of the mark on the workpiece (11), and the two connected adjustment rails (1a and 1b) are attached to the guide rail (12) using the magnetic connecting elements (3a and 3b).The adjustment rails (1a and 1b) are aligned perpendicular to the longitudinal axis of the guide rail (12). The two interconnected stop riders (4a and 4b) are then moved together until they touch the workpiece edge (18), and the knurled screws (7) are tightened. The set distance between the stop riders and the connecting elements (3a and 3b) is now precisely identical (synchronized) and fixed for both adjustment rails (1a and 1b). The two adjustment rails (1a and 1b) can now be separated and placed on the workpiece (11) as far apart as possible (preferably near the upper and lower workpiece edges) to optimally support the guide rail against rotation. Finally, the magnets in the groove (17) of the guide rail (12) are adjusted to approximately the same distance.The adjustment rails (1a and 1b) are set according to the selected positions and the adjustment rails (1a and 1b) are reconnected to the guide rail (12) via the magnets (13a and 13b) and the connecting elements (3a and 3b). The guide rail (12) can now be moved away from the workpiece edge (18) as far as necessary (in the . Fig. (2 to the right) until the two stop riders (4a and 4b) rest against the workpiece edge (18). If necessary, the guide rail can now be attached to the workpiece (11) using conventional means such as clamps. In this case, the adjustment rails (1a and 1b) with the stop riders (4a and 4b) can then be removed. This is particularly necessary for such cut-offs where the adjustment rails (1a and 1b) are used on the cut side of the workpiece, i.e., on the side of the cutting line (19) of the guide rail. The prior synchronization of the stop riders (4a and 4b) ensures a perfectly parallel cut with the saw (14) guided along the guide rail (12) in relation to the workpiece edge (18). If further sections are to be made on the same panel or on other panels, the parallel fence can be easily removed from the guide rail (12) without tools and reattached for the next cut.

[0010] Further embodiments are described in the dependent claims and in the following description.

[0011] The essential concept of the invention is that the guide rail is positioned at selectable intervals by means of a one-piece or multi-piece spacer, ensuring strict parallelism to a chosen workpiece edge. This parallelism is mechanically enforced. The moment the one-piece or multi-piece workpiece stop engages the selected workpiece edge, the guide rail is also precisely aligned parallel to that edge. Reading errors (such as those encountered with a design using two spacers where the distance must be individually adjusted via scales) are eliminated by this approach. This enforced parallelism can be achieved as described in the exemplary embodiment or through other designs. For example, a scissor mechanism or a parallelogram design would be advantageous.In this case, the workpiece stop would preferably be a single piece and could be continuously adjusted parallel to the longitudinal axis of the guide rail. In the case of the scissor-type design, one side of the scissor mechanism would be slidable along the groove, whereby fastening in the groove or fastening with magnets that slide within the groove would also be advisable.

[0012] Another key aspect of the invention is the easy (especially tool-free) attachment of the spacer to the guide rail, which is simultaneously very precise and unambiguous because the attachment is backlash-free: the magnetic attachment of the spacer to the guide rail eliminates any inaccuracies – here, too, there is a mechanical constraint of a backlash-free and unambiguous attachment, unlike, for example, if a clamping element were used that engages in the groove of the guide rail, where the position perpendicular to the longitudinal axis of the guide rail would not be clearly defined. Furthermore, the simple attachment and removal of the spacer eliminates the need to handle an otherwise very cumbersome construction – which is particularly relevant for longer spacers.

[0013] Furthermore, the use of a length scale on the spacer and a corresponding mark on the workpiece stop is planned. This eliminates the need for a mark on the workpiece as described in the exemplary embodiment. Since the exact cutting line varies depending on the saw and saw blade, as well as the guide rail used, the length scale is designed to be calibrated, specifically so that the zero position of the length scale can be precisely set to one side of the saw blade, allowing the exact cutting width to be read directly from the mark on the workpiece stop.

[0014] Another advantageous embodiment relates to a one- or multi-part retractable spacer with a similarly one- or multi-part workpiece stop that can be attached in various positions along the spacer. The spacer could, for example, lie flat on the workpiece between the workpiece stop and the guide rail and—like a tape measure—retract or roll up automatically beyond the workpiece stop, thus achieving a more favorable form factor (especially with shorter cutting widths). A further advantage would then be a (calibratable) length scale applied to the spacer.

[0015] In a further embodiment, the device is designed to be compatible with a perforated grid plate. The device is intended to allow the longitudinal axis of the guide rail, or a workpiece or workpiece stop, to be moved precisely perpendicular to one or more rows of holes in the grid and fixed in a desired position. This can be achieved, for example, by attaching cylindrical positioning elements to the underside of the spacer in various selectable positions. These elements are inserted or clamped into the selected holes of the grid plate with minimal or no play. In particular, expanding bolts are also provided that expand when fixed (e.g., by screwing) to the spacer, thus securing the spacer in the hole without any play.

[0016] The device is designed to be attached to the guide rail on both the side of the cutting line and the opposite side. If the same (external) groove of the guide rail is to be used in both cases, one possible solution is to allow the connecting element and spacer to be used on either side, the workpiece stop to be mounted on either side of the spacer, and the connecting element to be designed so that it can be attached to or in the groove from either side. Furthermore, the connecting element(s) are designed to be interchangeable to ensure compatibility with different guide rails.

[0017] In a further embodiment, the two adjustment rails and stop riders, and optionally also the connecting elements, are mechanically connected to each other. This connection allows not only for synchronizing the distance between the workpiece edge and the guide rail, but also for changing the distance between the adjustment rails. This can be achieved, for example, by round bars that are guided linearly in the stop riders and / or connecting elements by means of, for example, bores and can be clamped at selectable intervals. This eliminates the need for synchronizing the stop riders.

[0018] The main advantages achievable with the invention compared to conventional parallel stops for guide rails consist of higher precision with regard to parallelism, e.g., during a separation cut of a workpiece, since the device is backlash-free and the parallelism is mechanically enforced, and at the same time simplified handling through the easy-to-use coupling element, which at the same time allows for a clearly defined positioning of the spacer on the guide rail. Reference symbol list 1a Adjustment rail 1 1b Adjustment rail 2 2 elongated holes 3a Connecting element 1 3b Connecting element 2 4a Stop tab 1 4b Stop lever 2 5 positioning pins 6 positioning holes 7 knurled screw 10 Direction of movement 11 Workpiece 12 Guide rail 13a Magnet 1 13b Magnet 2 14 saw 15 Cutting direction 16 cutting width 17 Nut 18 workpiece edge 19 Section line

Claims

Device for guiding tools (14) on a workpiece (11) parallel to a workpiece edge (18), comprising: • a guide rail (12) along which the tool (14) is linearly displaceable, • at least two adjustment rails (1a and 1b) each with a stop (4a and 4b) and each with a coupling element, wherein a coupling element is attached to one end of each of the adjustment rails (1a and 1b) and is prepared to detachably attach the adjustment rails at different positions along the longitudinal axis of the guide rail (12), wherein each stop (4a and 4b) is slidably attached to one of the adjustment rails (1a and 1b) along the longitudinal axis of the adjustment rails (1a and 1b) and can be fixed in a selectable position, characterized in that the two stop (4a and 4b) have means for temporary mutual connection, so that an adjustment rail attached to the guide rail for a first adjustment rail can be (1a and 1b),The set distance between the stop rider and the guide rail is automatically transferred to a second adjustment rail attached to the guide rail (12) when the two stop riders (4a and 4b) are connected. This results in a stop edge for the workpiece (11) formed jointly by both stop riders (4a and 4b), which is strictly parallel to the longitudinal axis of the guide rail and thus forms a workpiece stop for the workpiece (11). After the length synchronization has thus been achieved, the adjustment rails (1a and 1b) can be separated from each other again to adjust a larger distance between them. Device according to claim 1, characterized in that the adjustment rails are designed to be rollable in and out. Device according to one of the above claims, characterized in that at least one of the at least two adjustment rails (1a or 1b) has a length scale and the associated stop rider (4a or 4b) has a marking for the length scale, for setting a distance between a workpiece edge (18) and a cutting line (19) of the tool (14) guided on the guide rail (12) and wherein the imaginary zero point of the length scale is optionally adjustable. Device according to one of the above claims, characterized in that at least one of the at least two adjustment rails of the spacer is prepared to receive one or more cylindrical positioning elements at selectable positions on the underside, for backlash-free fastening of the adjustment rails of the spacer in a perforated grid plate and alignment of the longitudinal axis of the guide rail (12) perpendicular to a row of holes of the perforated grid plate. Device according to one of the above claims, characterized in that the coupling element is formed from a permanent magnet (13a or 13b) which is slidable in a groove (17) of the guide rail (12) and / or can be fixed in a selected position along the groove (17) and a ferromagnetic connecting element (3a or 3b) which is connected to the adjusting rail (1a or 1b). Device according to claim 5 characterized in that the connecting elements (3a and 3b) have the same width as the stop riders (4a and 4b) and / or are designed to be connectable to each other. Device according to one of the above claims, characterized in that the stop riders (4a and 4b) have an upper groove in the width of the adjustment rails (1a and 1b) with which the stop riders (4a and 4b) are guided when moved along the adjustment rails (1a and 1b) and the adjustment rails (1a and 1b) have elongated holes through which the stop riders (4a and 4b) are fixed with a screw from the top of the adjustment rails (1a and 1b) at the selected distance to the guide rail (12). Device according to one of claims 5 to 7, characterized in that the adjustment rails (1a and 1b) and the connecting elements (3a and 3b) are prepared to be used on both sides, in particular such that the stop riders (4a and 4b) can be attached to the top or bottom of the adjustment rails (1a and 1b) and the connecting elements (3a and 3b) are prepared to be attached with a first side from the side of the cutting line (19) to the guide rail (12) and with a second side to be attached to the side of the guide rail (12) opposite the cutting line (19). Method for aligning a guide rail (12) for a tool (14) parallel to a workpiece edge (18) of a workpiece (11) to be machined, comprising the steps: a) placing the guide rail (12) on the workpiece (11), b) positioning the guide rail (12) at a desired distance to a selected workpiece edge (18), c) attaching two adjustment rails (1a and 1b), each having a stop (4a and 4b), to the guide rail (12) parallel to each other and perpendicular to the guide rail (12), d) connecting the two stop (4a and 4b) to each other so that a common contact edge for the selected workpiece edge (18) is formed, e) moving the connected stop (4a and 4b) until they are in contact with the selected workpiece edge (18) with the common contact edge,f) Fixing the two stop riders (4a and 4b) to the respective adjustment rails (1a and 1b) g) Separating the two stop riders (4a and 4b) and thus the two adjustment rails (1a and 1b) from each other, thereby increasing the distance between the adjustment rails (1a and 1b) to such an extent that the guide rail (12) is sufficiently supported laterally so that it cannot be rotated or pivoted horizontally relative to the selected workpiece edge. or: a) Setting a desired cutting width (16) by moving and fixing a first stop rider (4a) on a first adjustment rail (1a) using the scale on the first adjustment rail and a marking on the first stop rider (4a), b) Connecting the two adjustment rails (1a and 1b) to each other via the stop riders (4a and 4b) and connecting elements (3a and 3b),so that a common contact edge is obtained for the selected workpiece edge (18) and for the guide rail (12), c) fixing the second stop rider (4b) on the second adjustment rail (1b) at the transferred position, d) separating the two adjustment rails (1a and 1b) from each other, e) increasing the distance between the adjustment rails (1a and 1b) by moving or loosening and reconnecting them to the guide rail (12) to such an extent that the guide rail (12) is sufficiently supported laterally so that it cannot be rotated or pivoted horizontally relative to the selected workpiece edge.

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