WO2010142582A1

WO2010142582A1 - Scroll saw with an adjustable work table

Info

Publication number: WO2010142582A1
Application number: PCT/EP2010/057672
Authority: WO
Inventors: Helmut Scholz
Original assignee: Proxxon S.A.
Priority date: 2009-06-11
Filing date: 2010-06-02
Publication date: 2010-12-16
Also published as: DE102009025108B4; DE102009025108A1

Abstract

The invention relates to a scroll saw (10) comprising a bearing structure (12) for placing said scroll saw (10) onto a support, a worktable (20) supported by the bearing structure for supporting a workpiece which is to be sawn, an upper arm (22) extending in the longitudinal direction of the scroll saw (10) and below the work table (20), and a first clamping device (26) which is placed on the upper arm (22) and which is used to clamp a saw blade (30) above the work table (20) and a second clamping device for clamping the saw blade (30) below the work table. In order to allow the saw blade to pass along a straight connection line between the first and the second clamping devices (28), a continuous opening is arranged in the work table (20) between the first (26) and the second clamping devices. According to the invention, the work table (20) is arranged on the bearing structure (12) in such a manner that it can be displaced in the longitudinal direction of the scroll saw (10), and the opening (32) allows the saw blade (30) comprising a longitudinal slot (36) extending in the longitudinal direction of the scroll saw to extend up to the edge of the work table (20). Said work table (20) can be displaced in a position in which the connection line between the first and the second clamping devices (26, 28) extends in a spatial manner close to the work table (20).

Description

DECANTER SAW WITH ADJUSTABLE WORKING TABLE

Technical area

The present invention generally relates to a scroll saw, especially a scroll saw with adjustable work table.

State of the art

The term "scroll saw" generally refers to the motorized version of the fret saw. <br /> <br /> Scroll scroll saws are used in particular for precise curve and internal cuts, comprising a base housing that can be set up on a workbench and serves, among other things, as a supporting structure for a work table Base frame mounted saw arm extends over the work table and carries an upper chuck for the saw blade In the base housing below the work plate, a lower chuck blade is mounted vertically below the upper saw blade chuck unit The jigsaw blade is clamped and extended between the lower and upper chuck In the case of scroll saws of a first design, the lower clamping device has an electric drive mechanism which, during operation of the saw, causes an alternating lifting movement of the saw blade Clamping device here is a passive Hubteil integrated, which exerts a corresponding counterforce on the saw blade so that it is always subject to the right voltage. Such a scroll saw is sold, for example, by the applicant under the name "MINIMOT ™ scroll saw DS 220 / E". In scroll saws of a further type, the saw blade is clamped between two substantially parallel pivot arms, wherein the pivot arms are each pivotally mounted about a horizontal axis. The pivot arms are connected to a drive to produce the strokes of the saw blade.

The workpiece to be sawn is placed on the worktable of the scroll saw and pressed lightly against the fretsaw blade by hand. It can be done by hand freely on the work table, so that even complicated curved cuts can be executed precisely. In addition, the scroll saw can include a height-adjustable guide shoe that holds the saw blade on the workpiece surrounds. It is also known to install a blowing device in the scroll saw, and bring the blown air via flexible air ducts to the interface to blow away the sawdust and thus to ensure a clear view of the cutting line. In various sawing work, frequent loosening and clamping of the saw blade are required. In particular, when making internal cuts in a workpiece, the saw blade must first be passed through a prepared opening before the saw blade can be secured between the upper and lower jigs. Various devices are known for clamping the saw blade, which are relatively quick and easy Allow loosening and clamping of the saw blade. Such a quick-release device is known for example from utility model DE 20 2004 003 854 111.

The known quick release devices have indisputably contributed to simplify the loosening and clamping of the saw blade. Nevertheless, in particular the clamping remains a tricky matter.

From US Patent 5,228,376 a scroll saw with sliding work table is known. The work table is slidably mounted on two rods extending parallel to each other in the longitudinal direction of the scroll saw, which are coupled via a rotary joint to the support structure of the scroll saw.

Object of the invention

An object of the present invention is to simplify the clamping of the saw blade. This object is achieved by a scroll saw according to claim 1.

General description of the invention

A scroll saw usually includes a support structure for setting up the scroll saw on a base (such as a workbench), a supported by the support structure work table for supporting a workpiece to be sawn, extending in a longitudinal direction of the scroll saw above the work table upper arm, as well as a first jig attached to the upper arm for clamping a saw blade above the work table and a second clamping device for clamping the saw blade below the work table. For passing the saw blade along a straight line (hereinafter referred to as a connecting line) between the first and second jigs, a through hole is formed in the work table between the first and second jigs. In the scroll saw according to the invention the work table is slidably mounted on the support structure in the longitudinal direction of the scroll saw, and the opening for passing the saw blade comprises a longitudinal slot extending in the longitudinal direction of the scroll saw to an edge of the work table. Further, the worktable is slidable to a position (hereinafter referred to as maintenance position for the sake of simplicity) in which the connection line between the first and second jigs is spatially adjacent to the worktable. The scroll saw according to the invention simplifies the clamping of the saw blade in that the first and second clamping device are more accessible and, secondly, both are simultaneously in the field of vision of the user when the work table is moved to the maintenance position. Not negligible is also the advantage that the threading of the saw blade through the opening is eliminated. Due to the fact that the connecting line between the first and the second clamping device lies beyond the edge of the work table in the (imaginary) extension of the longitudinal slot, the user merely needs to clamp the saw blade and push the work table back into the working position. Sawing operations that require frequent replacement or re-tensioning of the saw blade can save a significant amount of time thanks to the present invention.

Preferably, the scroll saw comprises a guide shaft extending in the longitudinal direction of the scroll saw, to which the work table is slidably mounted with respect to the support structure. In this case, the shaft can be fastened to the support structure and the work table can be displaced as a slide on this shaft. In the preferred embodiment of the invention, however, the guide shaft is fixed to the work table, and the support structure has at least one sliding bearing on which the guide shaft can slide in the longitudinal direction of the scroll saw. In the maintenance position of the work table is preferably located on a stop on the support structure.

In the working position of the work table, the connecting line between the first and the second clamping device extends through the opening in the work table (ie not on the work table over). To ensure safe sawing in the working position of the work table is preferably locked in the working position.

According to an advantageous embodiment of the invention, the scroll saw comprises a tilting device for tilting the work table to a running in the longitudinal direction of the scroll saw axis of rotation. The tilting device allows to adjust the angle of inclination of the work table and gives the user the opportunity to make oblique cuts. Preferably, the scroll saw has a blocking device, which allows the tilting of the work table only in the working position. Such a blocking device could comprise a first blocking element on the support structure and a second blocking element on the work table, which are arranged so that they engage with each other when the work table is moved from the working position in the direction of the maintenance position. Once the blocking elements are engaged with each other, the worktable can no longer be tilted. Of course, the blocking elements also prevent a displacement of the work table from the working position if the work table is not aligned horizontally. Preferably, the opening for the passage of the saw blade has a subsequent to the longitudinal slot transverse slot, so that the work table can be tilted in the working position, without the saw blade comes into contact with it. The tilting device preferably comprises a hinge, via which the support structure and the work table are rotatably coupled to each other about the rotation axis. In order to set the angle of inclination of the work table, the work table according to an advantageous embodiment, a circular arc portion with a toothing, which lies in a plane perpendicular to the axis of rotation and is centered on the intersection of this plane and the axis of rotation. According to this embodiment, a lever with a latch element is provided on the support structure, which lever is mounted rotatably on the support structure about a lever axis parallel to the rotation axis, such that it assumes a first and a second angular position can, wherein the pawl member is in the first angular position of the lever with the toothing of the circular arc portion is engaged and spaced in the second angular position of the toothing of the circular arc portion. Further, the pawl member has an adjusting device by which a linear position of the pawl member on the lever in the first angular position is substantially tangential to the circular arc portion adjustable. This embodiment of the tilting device enables a rapid coarse adjustment of the angle of inclination in that the pawl element is brought into engagement with the toothing on the circular arc section. The fine adjustment of the inclination angle is done via the adjusting device. Preferably, the adjusting device is such that the position of the pawl member is at least a distance changed, which corresponds to the pitch (arc length of the pitch circle between two adjacent, equilateral tooth flanks) of the teeth.

The lever on which the pawl element is arranged, is preferably biased by a spring element in the first angular position. The lever may further comprise a locking element, by means of which the work table in the

Working position can be locked. Preferably, the locking element has a beveled end face on which the circular arc portion when moving the

Working table comes into working position into rest, whereby the lever is pressed in the second angular position. The lever may also have an actuating arm with which the user can bring the lever in the second angular position to make the rough adjustment. For a secure fixation of the

Worktable in the desired angle of inclination is preferably one

Locking screw provided for locking the lever in the first angular position.

Brief description of the figures

Further details and advantages of the invention can be taken from the following detailed description of a possible embodiment of the invention with reference to the accompanying figures. 1 shows a perspective view of a scroll saw according to the invention, the work table being in the working position; FIG. 2 is a perspective view of the scroll saw of FIG. 1 with the work table in the service position; FIG.

FIG. 3 is another perspective view of the scroll saw of FIG. 1 with the worktable in the service position; FIG. FIG. 4 is a perspective view of the scroll saw of FIG. 1; FIG. wherein the work table is tilted;

Fig. 5 is a perspective detail view of the blocking elements, which prevent a displacement of the work table when it is tilted;

FIG. 6 shows a further perspective detail view of the blocking elements from FIG. 5 with the work table tilted; FIG.

FIG. 7 shows a further perspective detailed view of the blocking elements from FIG. 5 when the work table has been moved out of the working position; FIG.

Fig. 8 is a detail view of the tilting device of the scroll saw.

DESCRIPTION OF AN EMBODIMENT OF THE INVENTION The scroll saw 10 shown in FIGS. 1 to 4 comprises a support structure 12 with which the scroll saw 10 can be mounted, e.g. can be placed on a workbench. In our example, the support structure 12 comprises a base plate 14 supporting the motor 16 of the scroll saw, and a support structure 18 to which the work table 20 and upper and lower swing arms 22, 24 are mounted. The pivot arms 22, 24 extend parallel to each other in the longitudinal direction of the scroll saw above and below the work table 20 and each have at one end a clamping device 26, 28 for the saw blade 30. The pivot arms 22, 24 are each pivotally mounted about a horizontal axis and coupled to each other so that they remain parallel to each other in their pivoting movement and move the saw blade 30 substantially along a line alternately upwards and downwards. The pivot arms 22, 24 are driven in a manner known per se by the motor 16.

The work table 20 has between the first and the second

Clamping device 26, 28 a through opening 32 for passing the saw blade 30 along the running between the jigs 26, 28 straight line. The work table 20 is in the longitudinal direction of the scroll saw 10th slidably mounted and tilted transversely to the longitudinal direction on the support structure 12. The opening 32 for the passage of the saw blade 30 comprises, on the one hand, a longitudinal slot 36 extending in the longitudinal direction as far as the front edge 34 of the work table 20 and, on the other hand, a transverse slot 38 adjoining it. The work table 20 can be moved between a working position (FIG ) and a maintenance position (FIGS. 2 and 3). In the working position, the connecting line between the first and second jigs 26, 28 passes through the opening 32 in the work table 20. In other words, the geometric intersection of the connecting line with the plane defined by the work table 20 lies within the working surface bounded by the work table 20. In the maintenance position, the line connecting the first and second jigs passes the work table 20. In this case, the point of intersection of the connecting line with the plane defined by the work table 20 lies outside the working surface delimited by the work table 20, more precisely, in the imaginary extension of the longitudinal slit 36 beyond the front edge 34 of the work table 20. Advantages of the movable work table 20 are, as already explained above, that the clamping devices 26, 28 are more easily accessible, and that the threading of the saw blade 30 through the opening 32 is eliminated.

In the working position of the work table 20 can be tilted transversely to the longitudinal direction to facilitate oblique cuts. As best seen in Figure 4, in the scroll saw 10, a rotary thrust joint is present, which allows moving and tilting of the work table 20. On the underside of the work table 20 is fixed as a guide shaft extending in the longitudinal direction of a circular cylindrical rod 40 which is supported by plain bearings 42 on the support structure 12. The plain bearings 42 allow both an axial and a rotational movement. However, blocking elements prevent the worktable 20 from being tilted when not in the working position. The plain bearings 42 can also serve as stop elements which prevent axial movement beyond the working or maintenance position. In the example shown, the axis of rotation of the tilting device extends horizontally under the work table at a certain distance from the working surface and parallel to the vertical plane, which is spanned by the saw blade and the pivoting arms. Because in this configuration the intersection of the line between the jigs 26, 28 and shifts the work surface, when the work table 20 is tilted, the transverse slot 38 is necessary to avoid that the saw blade 30 and / or the work table 20 is damaged when tilted. In another embodiment of the invention in which the geometry is chosen such that the axis of rotation of the tilting device extends in the working plane and intersects the connecting line between the clamping devices, the transverse slot can be shorter or optionally omitted (if the longitudinal slot is wide enough).

Detailed views of the blocking elements are shown in Figures 5 to 7. A first blocking element (in the form of a rail 44) is arranged on the support structure 12 and a second blocking element (in the form of a C-shaped profile piece 46) on the work table 20. The two blocking elements are arranged so that they engage with each other when the work table 20 is moved from the working position in the direction of the maintenance position. In Figure 5, the work table 20 is in the working position and is aligned horizontally. The blocking elements are not in engagement with each other, so that the work table 20 can be inclined relative to the horizontal plane. In Figure 6, the work table 20 is tilted in the working position by a certain angle. Figure 7 shows how the blocking elements cooperate when the work table is displaced in the longitudinal direction. The C-shaped profile piece 46 engages a corresponding flange of the rail 44th

The tilting device will now be described in more detail with reference to Figures 4 and 8. The work table 20 has a shaped part 48 with a toothed circular arc section 50, which lies in a plane perpendicular to the axis of rotation and is centered on the intersection of this plane and the axis of rotation. A lever 52 with a pawl element 54 is rotatably mounted on the support structure 12 about a lever axis parallel to the axis of rotation, so that the lever 52 can assume a first and a second angular position. In the first angular position of the lever 52, the pawl member 54 engages the toothing of the circular arc portion (FIG. 4) while being spaced from the toothing of the circular arc portion 50 in the second angular position of the lever 52 (FIG. 8). The pawl member 54 includes an adjustment screw 56 and a pulley 58, whose position on the lever 52 in the tangential direction to the circular arc portion 50 with the adjusting screw 56 is adjustable. About the teeth comes a coarse adjustment of the angle of inclination of the work table 20, because the disc 58 can engage only in certain angular intervals (eg 10 degrees) in a tooth gap of the toothed circular arc portion 50. For fine adjustment, the disk 58 can be moved by turning the fine adjustment screw 56 along the axis of the fine adjustment screw 56. In this case, the position of the disk 58 can be changed at least by a distance corresponding to a pitch of the toothing of the circular arc section 50. This ensures that all tilt angles can be set within a certain range (eg from -30 degrees to 50 degrees). On the molding 48, a scale 68 allows the user to read the angle of inclination of the work table 20, or set to a precise value.

The lever 52 is biased by a spring element (shown in the example as Schraubenzugfeder 60) in the first angular position and further comprises an actuating arm 62, with which the user can bring the lever 52 against the spring force in the second angular position. Finally, a locking element 64 is attached to the lever 52, with which the work table 20 can be locked in the working position. The locking element 64 in the form of a latching nose has a beveled end face which is arranged on the lever 52 such that the shaped part 48 comes into contact with the bevelled end face when the work table 20 is moved into the working position and presses the lever 52 into the second angular position. Due to the restoring force of the spring element 60, the lever 52 snaps back as soon as the work table 20 has reached the working position and locks it. To then move the work table 20 back to the maintenance position, the lever 52 is manually pressed into the second angular position and the work table 20 is moved. To fix the lever 52 in the first angular position is a locking screw 66. If this screw is tightened, it must first be solved to move the work table 20 or adjust the inclination angle. The locking screw 66 clamped with the locking element 64, the molding 48 and thus the table firmly in the set position, thus preventing unintentional actuation of the rocker arm. Explanations:

10 scroll saw

12 carrying structure

14 base

16 engine

18 support structure

20 work table

22 Upper swivel arm

24 lower swivel arm

26 Upper jig

28 Lower clamping device

30 saw blade

32 opening

34 leading edge

36 longitudinal slot

38 transverse slot

40 pole

42 plain bearings

44 rail

46 C-shaped profile piece

48 molded part

50 toothed circular arc section

52 levers

54 pawl element

56 Adjustment screw

58 disc

60 tension coil spring

62 operating arm

64 locking element

66 locking screw

68 scale

Claims

claims

1. scroll saw (10), comprising a support structure (12) for setting up the scroll saw on a base; a work table (20) carried by the support structure for supporting a workpiece to be sawn; an upper arm (22) extending above the work table in a longitudinal direction of the scroll saw; a mounted on the upper arm first jig (26) for

Clamping a saw blade (30) above the work table; a second clamping device (28) for clamping the saw blade below the work table; the worktable between the first and second jigs having a through opening (32) for passing the saw blade along a straight line connecting the first and second jigs

Clamping device comprises; characterized in that the work table in the longitudinal direction of

Scroll roller is slidably mounted on the support structure, that the opening for passing the saw blade extends in the longitudinal direction of the

Scroll saw up to an edge of the work table extending longitudinal slot

(36), and that the work table is displaceable to a maintenance position in which the connection line between the first and the second

Clamping device runs spatially next to the work table.

2. scroll saw according to claim 1, comprising a extending in the longitudinal direction of the scroll saw guide shaft (40) on which the worktable is slidably mounted with respect to the support structure.

3. scroll saw according to claim 2, wherein the guide shaft is fixed to the work table, the support structure has at least one sliding bearing (42) through which the guide shaft can slide in the longitudinal direction of the scroll saw.

4. scroll saw according to any one of claims 1 to 3, wherein the support structure has a stop on which the work table in the maintenance position is applied.

5. scroll saw according to any one of claims 1 to 4, wherein the work table is displaceable in a working position in which the connecting line between the first and the second clamping device through the opening in the work table, and wherein the work table can be locked in the working position.

6. scroll saw according to claim 5, comprising a tilting device for tilting the work table to a running in the longitudinal direction of the scroll saw axis of rotation.

The scroll saw according to claim 6, comprising a blocking device (44, 46) which permits tilting of the work table only in the working position.

The scroll saw according to claim 7, wherein the blocking device comprises a first blocking element (44) on the support structure and a second blocking element (46) on the work table, and wherein the first and second blocking elements are arranged to engage each other when the work table is moved from the working position in the direction of the maintenance position.

A scroll saw according to any of claims 6 to 8, wherein the opening (32) for passing the saw blade has a transverse slot (38) adjoining the longitudinal slot,

The scroll saw according to any one of claims 6 to 9, wherein the tilting device comprises a hinge via which the support structure and the work table are rotatably coupled to each other about the rotation axis, wherein the work table has a circular arc portion (50) with a toothing, in a plane is perpendicular to the axis of rotation and centered on the intersection of this plane and the axis of rotation, wherein on the support structure, a lever (52) with a pawl member (54) is provided which is rotatably mounted about a lever axis parallel to the axis of rotation on the support structure, in such that it can assume a first and a second angular position, wherein the pawl member is in the first angular position of the lever with the toothing of the circular arc portion is engaged and spaced in the second angular position of the toothing of the circular arc portion; and that the pawl member has an adjusting device (56) by which a position of the pawl member on the lever in the first angular position is substantially tangential to the circular arc portion adjustable.

11. scroll saw according to claim 10, wherein the lever (52) by means of a spring element (60) is biased in the first angular position.

12. scroll saw according to claim 11, wherein the lever comprises a locking element (64), by means of which the work table can be locked in the working position.

13. Scroll saw according to claim 12, wherein the locking element (64) has a beveled end face, such that the arcuate portion comes when moving the work table into the working position with the bevelled end face in support and presses the lever in the second angular position.

The scroll saw according to any one of claims 10 to 13, wherein the lever comprises an actuating arm (62).

A scroll saw according to any one of claims 10 to 14, comprising a locking screw (66) for fixing the lever in the first angular position.