EP4275853A1 - Sawing device with an emergency braking unit and method for readying a triggered emergency braking unit for use - Google Patents

Abstract

A sawing device (10) is described with a frame, a circular disk-shaped saw blade (12) which is rotatably mounted with respect to the frame, and an emergency brake unit (24). The emergency brake unit (24) comprises a blocking element (26), an actuator unit (32) and a control unit (34). The blocking element (26) has a bearing section (38) and a head section (42), which is designed to selectively engage in the saw blade (12) for braking. The actuator unit (32) is coupled to the blocking element (26) at least in a normal position of the blocking element (26) in such a way that the blocking element (26) can be selectively brought into engagement with the saw blade (12) by means of the actuator unit (32). In addition, the blocking element (26) can optionally be removed from the frame separately from the actuator unit (32) and/or separately from the control unit (34). A method for making a triggered emergency brake unit (24) of a sawing device (10) ready for use is also presented. In this context, a blocking element (26) is dismantled separately from the actuator unit (32) and/or separately from the control unit (34) and an unused blocking element (26) is mounted.

Description

The invention relates to a sawing device with a frame, a circular disk-shaped saw blade which is rotatably mounted with respect to the frame, and an emergency brake unit.

In addition, the invention is directed to a method for preparing a triggered emergency brake unit of a sawing device for use.

Sawing devices with emergency braking units are known from the prior art.

The emergency brake unit serves to stop the rotation of the saw blade if there is an impending or existing risk of injury. In this way, injuries to users of the sawing devices are avoided or at least reduced in severity. In other words, safe operation of the sawing device is guaranteed.

Particularly in applications in which the emergency brake unit is expected to be triggered comparatively frequently, it is important in the interests of work efficiency that a saw with a triggered emergency brake unit can be made ready for use again quickly and easily. Only then can you continue working on the processing task in a timely manner. In this way, safe operation of the sawing device can be combined with high work efficiency. From an economic point of view, the costs of triggering the emergency braking unit and making a triggered emergency braking unit ready for use should also be as low as possible.

It is therefore the object of the present invention to provide sawing devices and associated methods for making a triggered emergency brake unit ready for use
AS:TOP
improve so that increased work efficiency can be achieved with a known high level of operational reliability.

The task is solved by a sawing device with a frame, a circular disk-shaped saw blade which is rotatably mounted in relation to the frame and an emergency brake unit. The emergency brake unit comprises a blocking element, an actuator unit and a control unit, which is designed integrally with the actuator unit or is coupled to the actuator unit in terms of signaling. The blocking element comprises a bearing section, via which the blocking element is mounted on the frame, and a head section. The head section is designed to selectively engage in the saw blade for braking. The actuator unit is coupled to the blocking element at least in a normal position of the blocking element in such a way that the blocking element can be selectively brought into engagement with the saw blade by means of the actuator unit. In addition, the blocking element can optionally be removed from the frame separately from the actuator unit and/or separately from the control unit. In the present case, the normal position of the blocking element is to be understood as the position in which it has not yet engaged with the saw blade. The normal position can therefore also be referred to as the untriggered position. In addition, dismantled separately from the actuator unit and/or separately from the control unit means that the blocking element can be dismantled from the sawing device without the actuator unit and/or the control unit of the emergency brake unit having to be dismantled at the same time. Of course, this does not include mounting elements, bearing elements, holding elements and fastening elements by means of which the blocking element is mounted. In other words, the blocking element can be individually dismantled with respect to the actuator unit and/or the control unit. The blocking element can therefore be replaced alone or individually. The actuator unit and/or the control unit remain mounted on the sawing device during such an exchange. This means that the blocking element can be dismantled quickly and easily. This applies in principle to all operating states of the sawing device and the emergency brake unit, but in particular to a state after the emergency brake unit has been triggered, ie when the blocking element is in the Saw blade engages or has engaged the saw blade. This means that the emergency brake unit and the sawing device can be put back into operation quickly and easily after the emergency brake unit has been triggered. This means that a processing task can be continued and completed in a timely manner. The fact that the blocking element can be individually replaced also means that triggering the emergency brake unit and making the triggered emergency brake unit ready for use incurs comparatively few costs.

In a preferred embodiment, the blocking element can be dismantled separately from all other components of the emergency brake unit. In other words, the blocking element can be individually dismantled with respect to all other components of the emergency brake unit. The effects and advantages explained are particularly high.

In a further preferred embodiment, the blocking element, the actuator unit and the control unit of the emergency brake unit can each be dismantled separately from all other components of the emergency brake unit. In other words, the blocking element can be individually dismantled with respect to all other components of the emergency brake unit. In addition, the actuator unit can be individually dismantled with respect to all other components of the emergency brake unit. In addition, the control unit of the emergency brake unit can be individually dismantled with respect to all other components of the emergency brake unit. Individual components of the emergency brake unit can therefore be easily replaced, repaired and/or maintained.

In a first alternative, the control unit of the emergency brake unit can be designed integrally with a motor control unit, which serves to control a drive motor designed to drive the saw blade. In a second alternative, the engine control unit and the control unit of the emergency brake unit are designed separately. However, they can be connected to one another in terms of signaling so that the drive motor can be deactivated easily and reliably when the emergency brake unit is triggered.

The effects and advantages of the invention mentioned are particularly clear in comparison to known emergency braking units for sawing devices. With such emergency braking units The blocking element, the associated actuator unit and the control unit are designed as a module. After the emergency brake unit is triggered, the entire module, ie both the blocking element and the actuator unit and the control unit, must always be replaced.

In this context, a sawing device with a circular disk-shaped saw blade can also be referred to as a circular sawing device or simply as a circular saw. Examples of such sawing devices are cross-cut saws, table saws, hand-held circular saws and plunge saws.

Blocking elements for emergency braking units of sawing devices are also colloquially referred to as brake wedges. This is the case regardless of whether the blocking element is wedge-shaped or acts as a wedge.

It is also understood that the emergency brake unit is coupled to a sensor unit for detecting an actual or imminent contact with the saw blade by a user and is operated depending on a detection result of the sensor unit. In this way, the emergency braking unit can be triggered in a timely and targeted manner. Injury to the user of the sawing device can be completely prevented or at least limited in severity.

In this context, the actuator unit of the emergency brake unit can comprise an actuator that can be triggered selectively, in particular depending on the detection result. By means of the actuator, the blocking element, more precisely the associated head section, can be brought quickly and reliably into engagement with the saw blade. The actuator includes, for example, a lifting magnet or a shape memory alloy actuator. It is also possible to use a preloaded spring, which can be released using a fusible wire, as an actuator.

The sawing device can include a guide element. The guide element is designed to guide the blocking element at least along a guide direction which runs at least in sections parallel to a circumferential direction of the saw blade. That is This is particularly important when the blocking element engages the saw blade with its head section. In such a situation, the kinetic energy of the rotation of the saw blade must be specifically introduced into the blocking element and absorbed by the blocking element. The guide element prevents the blocking element from being deformed or displaced in an undesirable manner. A guide along a guide direction that runs at least in sections parallel to a circumferential direction of the saw blade allows the blocking element to move parallel to the circumferential direction. A movement parallel to an axial direction of the saw blade is prevented by the guide element. A movement in a direction radial to the saw blade can be permitted or prevented depending on the application. The guide element consequently ensures that the saw blade is braked with high reliability by means of the blocking element.

According to one embodiment, the blocking element is connected to the frame via a bearing element. The bearing element can be individually removed from the sawing device, i.e. from the frame. In this embodiment, both the bearing element and the blocking element can be individually dismantled. The unique demountability of the bearing element causes the unique demountability of the blocking element. In other words, the bearing element must be dismantled in order to be able to dismantle the blocking element. Further components of the emergency brake unit do not need to be dismantled. On the one hand, the individually removable bearing element allows the blocking element to be reliably stored on the frame, so that comparatively high forces can also be transmitted between the blocking element and the frame. On the other hand, the blocking element remains easy and quick to dismantle.

The sawing device can include a locking mechanism by means of which the bearing element can be selectively locked to the frame and selectively unlocked from the frame. The bearing element is therefore secured to the frame in such a way that it does not separate from the frame in an undesirable manner.

Examples of locking mechanisms include a thread into which the bearing element is screwed, an eccentric mechanism via which the bearing element is clamped and locking wings which are arranged at one end of the bearing element and positively engage behind an associated frame section in the locked state.

In one variant, the guide element is mounted on the frame by means of the bearing element. The bearing element thus serves both to support the blocking element and to support the guide element. Compared to storing the blocking element and the guide element with separate, specific bearing elements, components can thus be saved. This allows the sawing device to be constructed in a comparatively simple and compact manner.

In another alternative, the blocking element is mounted on the frame by means of a fixed bearing element. In addition, a holding element is provided for holding the blocking element on the bearing element. The blocking element can be reliably stored on the frame using the fixed bearing element. In particular, comparatively high forces can be transmitted between the blocking element and the frame. To dismantle the blocking element, only the holding element has to be dismantled or moved into a release position. This means that the blocking element can be removed quickly and easily.

The holding element can also be individually removable from the bearing element. In this embodiment, both the holding element and the blocking element can be individually dismantled. The unique demountability of the holding element causes the unique demountability of the blocking element. In other words, the holding element must be dismantled in order to be able to dismantle the blocking element. Further components of the emergency brake unit do not need to be dismantled.

Examples of holding elements include a nut that is screwed onto the bearing element and locking rings that are positively or non-positively coupled to the bearing element.

In one embodiment, the holding element is formed by a section of the guide element. A section of the guide element is therefore designed to to hold the blocking element on the bearing element. In particular, such a section of the guide element blocks a movement of the blocking element along an extension direction of the bearing element, ie along an axial direction of the bearing element. In this context, the guide element can be mounted separately on the frame, so that it can optionally assume an operating position in which it holds the blocking element on the bearing element and can assume a release position in which it enables the blocking element to be dismantled from the bearing element.

The bearing element can be a bearing pin. The blocking element can be rotatably mounted via the bearing pin. Such a bearing element has a comparatively simple structure and can reliably store the blocking element. The rotatable bearing ensures that the blocking element can be easily and reliably brought into engagement with the saw blade.

In one embodiment, the blocking element comprises a coupling section via which the blocking element is coupled to the actuator unit at least in the normal position. The coupling section can be positioned at an end of the blocking element opposite the bearing section. The blocking element can thus be selectively brought into engagement with the saw blade by means of the actuator unit via the coupling section. Positioning the coupling section at an end of the blocking element opposite the bearing section ensures that the blocking element can engage with the saw blade with high reliability and precision. Undesirable interactions between the coupling section and the bearing section are excluded or at least reduced to a small extent.

In this context, a clamping element can be provided which, at least in the normal position, non-positively couples the actuator unit to the blocking element. Alternatively, a form-fitting element can be provided which, at least in the normal position, positively couples the actuator unit to the blocking element. The actuator unit and the blocking element are therefore simple and reliable, at least in the normal position coupled way. Such a coupling can also be released and restored quickly and easily when the blocking element is replaced.

In an end position, the blocking element can be decoupled from at least a section of the actuator unit. The end position refers to a position of the blocking element after it has been brought into engagement with the saw blade by means of the actuator unit, i.e. a position after the emergency brake unit has been triggered. Because the coupling to the actuator unit has already been released, the blocking element can be particularly easily removed from the emergency brake unit and replaced with an unused blocking element.

The actuator unit can also be individually removable from the frame. Again, the singular dismantling ability refers to the remaining components of the emergency brake unit. If necessary, the actuator unit alone can be replaced without having to dismantle other components of the emergency brake unit at the same time. The emergency brake unit is therefore particularly easy to repair. It is emphasized that in a preferred embodiment the actuator unit is designed to be used in a plurality of triggering processes of the emergency brake unit. By default, the actuator unit does not have to be replaced after the emergency brake unit has been triggered.

Preferably, at least one of the blocking element and the actuator unit can be removed without tools. In other words, at least one of the blocking element and the actuator unit can be dismantled by hand, in particular without tools. This makes dismantling particularly easy.

According to a variant, in the normal position, the bearing section and the head section are essentially the same distance from a central axis of the saw blade. Consequently, the blocking element is, on the one hand, arranged in a space-saving manner within the sawing device and, on the other hand, positioned so that the head section of the blocking element only has to overcome a comparatively small distance in order to engage in the saw blade. Furthermore, such an arrangement can reliably introduce forces into the blocking element support over its bearing section. Overall, the saw blade can be brought to a standstill comparatively quickly and reliably.

In addition, it can be provided that the blocking element comprises a deformation section which lies between the bearing section and the head section and/or connects the bearing section and the head section to one another. The deformation section can be arcuate and designed to be plastically shortened along an arc circumferential direction in order to brake the saw blade. The kinetic energy of the rotation of the saw blade can therefore be reliably and specifically converted into a plastic shortening of the deformation section. This is caused in particular by the arcuate shape of the deformation section and its position between the bearing section and the head section. Therefore, rotation of the saw blade can be stopped in a comparatively short time. Since the deformation section is specifically designed to be plastically shortened along the circumferential direction of the arch, it can absorb a comparatively large amount of kinetic energy with respect to the installation space required by the deformation section and convert it into a plastic shortening. This also means that forces resulting from the braking of the saw blade are reliably and specifically absorbed by the deformation section. As a result, only comparatively small forces act on the other components of the emergency brake unit. The same applies to components of the sawing device. Consequently, the functionality of the remaining components of the emergency braking unit and the components of the sawing device are not affected by a braking process brought about by means of the blocking element. This applies in particular to the saw blade, which can continue to be used when the sawing device is put back into operation.

The arcuate deformation section preferably runs concentrically to the circular disk-shaped saw blade.

• Demontieren des Blockierelements separat von einer Aktuatoreinheit der Notbremseinheit und/oder separat von einer Steuerungseinheit der Notbremseinheit, wobei das Blockierelement in das Sägeblatt eingreift oder mit dem Sägeblatt in Eingriff stand,
• Montieren eines unbenutzten Blockierelements.

Furthermore, the task is solved by a method for making a triggered emergency brake unit of a sawing device ready for use. The sawing device includes a circular disk-shaped saw blade. The emergency brake unit has a blocking element that does this is designed to selectively intervene in the saw blade in order to brake the saw blade. The procedure includes the following steps:

• Dismantling the blocking element separately from an actuator unit of the emergency brake unit and / or separately from a control unit of the emergency brake unit, wherein the blocking element engages in the saw blade or was in engagement with the saw blade,
• Installing an unused blocking element.

In this context, a state arises in which the blocking element engages with the saw blade or was in engagement with the saw blade when the emergency brake unit was triggered and the saw blade was braked by means of the blocking element. In the case of emergency brake units of the type relevant here, as a result of the emergency brake unit being triggered, the blocking element, which is damaged and/or deformed by the triggering, must be replaced by an unused blocking element. As already mentioned, against this background, dismantling the blocking element separately from an actuator unit of the emergency brake unit and/or separately from a control unit of the emergency brake unit means that the blocking element can be dismantled from the sawing device without simultaneously removing the actuator unit of the emergency brake unit and/or the control unit The emergency brake unit must or must be dismantled. As already mentioned, this does not include mounting elements, bearing elements, holding elements and fastening elements by means of which the blocking element is mounted. In this context, one can also speak of a singular dismantling of the blocking element, with singular again referring to the actuator unit and/or the control unit of the emergency brake unit. The blocking element can therefore be replaced alone or individually in order to make the sawing device ready for use. The actuator unit and/or the control unit of the emergency brake unit remain or remains mounted on the sawing device during such a replacement. The blocking element can therefore be quickly and easily replaced with an unused blocking element. This means that the emergency brake unit and the sawing device can be made ready for use quickly and easily after the emergency brake unit has been triggered. A processing task can can therefore be continued and completed in a timely manner. The fact that the blocking element can be individually replaced also means that triggering the emergency brake unit and making the triggered emergency brake unit ready for use incurs comparatively few costs.

In a preferred embodiment, the blocking element is dismantled separately from all other components of the emergency brake unit. In other words, the blocking element is dismantled individually with respect to all other components of the emergency brake unit. The effects and advantages explained are particularly high.

In a further preferred embodiment, the blocking element, the actuator unit and the control unit of the emergency brake unit are each dismantled separately from all other components of the emergency brake unit. In other words, the blocking element is dismantled individually with respect to all other components of the emergency brake unit. In addition, the actuator unit is individually dismantled with respect to all other components of the emergency brake unit. In addition, the control unit of the emergency brake unit is individually dismantled with respect to all other components of the emergency brake unit. Consequently, individual components of the emergency brake unit can be easily replaced, repaired and/or maintained.

In one variant, when mounting the unused blocking element, the unused blocking element is coupled to an actuator unit of the emergency brake unit. So the actuator unit is not replaced. By coupling, the blocking element can be selectively brought into engagement with the saw blade by means of the actuator unit in a subsequent operation of the sawing device.

In one embodiment, in order to dismantle the blocking element, a bearing element, by means of which the blocking element is mounted in the sawing device, is dismantled. Alternatively, a holding element is removed from a fixed bearing element, by means of which the blocking element is mounted in the sawing device. This can happen in both variants Blocking element can be dismantled quickly and easily. This can preferably be done without tools.

The holding element can be formed by a section of a guide element and the removal of the holding element from the fixed bearing element can include moving the guide element into a release position. The movement into the release position includes, for example, folding, pivoting, rotating and/or pushing the guide element. The guide element is preferably not separated from the frame of the sawing device. In this way, the holding element can be removed from the fixed bearing element particularly quickly and easily. The blocking element can therefore be replaced particularly quickly and easily.

Figur 1

eine erfindungsgemäße Sägevorrichtung in einer perspektivischen Ansicht, wobei die erfindungsgemäße Sägevorrichtung eine Notbremseinheit umfasst, die mit einem Blockierelement ausgestattet ist und mittels eines erfindungsgemäßen Verfahrens einsatzbereit gemacht werden kann,

Figur 2

die Sägevorrichtung aus Figur 1 in einer Seitenansicht, wobei ein Führungselement der Notbremseinheit fortgelassen ist,

Figur 3

Teile der Sägevorrichtung aus den Figuren 1 und 2 in einer separaten Ansicht,

Figur 4

eine Detailansicht des Blockierelements,

Figuren 5 bis 8

Teile der Sägevorrichtung aus den Figuren 1 und 2 zu verschiedenen Zeitpunkten nach dem Auslösen der Notbremseinheit,

Figur 9

einen Verlauf einer vom Blockierelement aufgenommenen Kraft über der Zeit nach dem Auslösen der Notbremseinheit,

Figur 10

Teile der Sägevorrichtung aus den Figuren 1 und 2 beim Montieren des Blockierelements,

Figuren 11 bis 14

alternative Ausführungen zum Halten des Blockierelements in einer Normal stellung,

Figur 15

Teile einer Sägevorrichtung gemäß einer alternativen Ausführungsform,

Figur 16

Teile einer Sägevorrichtung gemäß noch einer alternativen Ausführungsform,

Figur 17

Teile einer Sägevorrichtung gemäß einer weiteren alternativen Ausführungsform, und

Figur 18

eine zusätzliche Ausführungsform einer erfindungsgemäßen Sägevorrichtung.

The invention is explained below using various exemplary embodiments shown in the accompanying drawings. Show it:

Figure 1

a sawing device according to the invention in a perspective view, the sawing device according to the invention comprising an emergency brake unit which is equipped with a blocking element and can be made ready for use by means of a method according to the invention,

Figure 2

the sawing device Figure 1 in a side view, with a guide element of the emergency brake unit omitted,

Figure 3

Parts of the sawing device from the Figures 1 and 2 in a separate view,

Figure 4

a detailed view of the blocking element,

Figures 5 to 8

Parts of the sawing device from the Figures 1 and 2 at different times after the emergency brake unit is triggered,

Figure 9

a curve of a force absorbed by the blocking element over time after the emergency brake unit has been triggered,

Figure 10

Parts of the sawing device from the Figures 1 and 2 when installing the blocking element,

Figures 11 to 14

alternative versions for holding the blocking element in a normal position,

Figure 15

Parts of a sawing device according to an alternative embodiment,

Figure 16

Parts of a sawing device according to yet another alternative embodiment,

Figure 17

Parts of a sawing device according to a further alternative embodiment, and

Figure 18

an additional embodiment of a sawing device according to the invention.

The Figures 1 and 2 show a sawing device 10 with a circular disk-shaped saw blade 12. In the example shown, the sawing device 10 is a cross-cut saw.

The sawing device 10 comprises a base assembly 14 and an arm assembly 16 rotatably mounted thereon.

The base assembly 14 has a support surface 18 on which a component to be processed, i.e. to be sawn off or sawn in, can be positioned.

Furthermore, the saw blade 12 can be set in rotation about a central axis A by actuating a drive motor M coupled to it and can be brought into interaction with the component to be machined by displacing the arm assembly 16 relative to the base assembly 14.

The arm assembly 16 is shifted relative to the base assembly 14 manually in the example shown.

The arm assembly 16 or, more generally speaking, the sawing device 10 comprises a frame 20 on which a drive shaft 22 is mounted in a rotationally drivable manner. The drive shaft 22 is drivingly coupled to the drive motor M. The saw blade 12 is fixed on the drive shaft 22, so that the saw blade 12 can be driven in rotation in a known manner.

The sawing device 10 is also equipped with an emergency brake unit 24, which is in the Figures 3 and 4 can be seen in detail.

For better visibility of the emergency brake unit 24 is in the Figures 1 and 2 in an area G, a housing part is not shown. On the one hand, such a housing part serves to remove workpiece particles, for example sawdust or dust, which are generated by using the sawing device 10. On the other hand, in the illustrated embodiment, a section of the handle provided at the end of the arm assembly 16 is formed by means of such a housing part. Furthermore, the housing part serves to cover the saw blade 12.

The emergency brake unit 24 comprises a blocking element 26, which is rotatably mounted on the sawing device 10 via a bearing element 28 fixed to the frame 20 in the form of a fixed bearing pin 30 in such a way that it can selectively engage in the saw blade 12 to brake the saw blade 12.

In addition, the emergency brake unit 24 includes an actuator unit 32, which is designed to selectively bring the blocking element 26 into engagement with the saw blade 12.

In the example shown, the actuator unit 32 includes an electrically controllable lifting magnet, which is not shown in more detail in the figures.

The emergency brake unit 24 also includes an associated control unit 34.

In the illustrated embodiment, the control unit 34 is designed and arranged separately from the actuator unit 32 (see, for example, Figures 3 to 8 ). The actuator unit 32 and the control unit 34 are coupled via a signal line for signaling purposes.

This configuration means that the actuator unit 32 and the control unit 34 can be dismantled separately from each other. This makes replacement, repair or maintenance easier.

The control unit 34 is coupled to a sensor unit known per se for detecting actual or imminent contact with the saw blade 12 by a user.

The actuator unit 32 can thus be operated depending on a detection result of the sensor unit.

The emergency brake unit 24 also has a guide element 36, which is mounted on the frame 20 and guides a movement of the blocking element 26 along a guide direction F, as will be explained in detail below.

The blocking element 26 is located in the Figures 3 and 4 in a normal position. In this position, the blocking element is arranged parallel to a circumferential direction U of the saw blade 12.

The blocking element 26 is made up of three sections.

The blocking element 26 includes a bearing section 38.

In the illustrated embodiment, the bearing section 38 is sleeve-shaped, i.e. the bearing section 38 comprises a circular cylindrical bearing opening 40, which is delimited by a wall 41 with a substantially constant wall thickness.

The fixed bearing pin 30 is accommodated in the bearing opening 40, so that the blocking element 26 is rotatably mounted on the frame 20 of the sawing device 10 via the bearing section 38 and the bearing pin 30.

The blocking element 26 further comprises a head section 42.

The head section 42 is provided at an end of the blocking element 26 opposite the bearing section 38.

The head section 42 is designed to engage in the saw blade 12 when the emergency brake unit 24 is actuated, i.e. driven by the actuator unit 32, in order to ideally brake it to a standstill.

In this context, the head section 42 includes a coupling section 44.

The coupling section 44 is positioned at an end of the blocking element 26 opposite the bearing section 38.

The coupling section 44 is also positioned radially on the outside of the head section 42.

The coupling section 44 serves two different functions.

On the one hand, the coupling section 44 is designed to introduce an actuating force generated by the actuator unit 32 into the blocking element 26, so that the head section 42 can engage in the saw blade 12.

On the other hand, the coupling section 44 serves to hold the blocking element 26 at least in the in Figures 3 and 4 to fix or lock the normal position shown relative to the frame 20. The head section 42 is thus prevented from engaging with the saw blade 12 in the normal position.

The functions of force introduction and locking can be implemented separately from one another or together, ie combined. The latter is the case in the embodiments Figures 1 to 10 the case.

Here the coupling section 44 includes two coupling openings 46.

In addition, a U-shaped positive locking element 48 is provided, which is fastened on the one hand to the actuator unit 32, e.g. B. positively, and on the other hand has complementary knobs to the coupling openings 46, which engage in the coupling openings 46. The form-fitting element 48 is therefore positively coupled to both the blocking element 26 and the actuator unit 32.

Thus, on the one hand, an actuating force generated by the actuator unit 32 can be introduced into the blocking element 26 via the positive locking element 48. On the other hand, the blocking element 26 is locked in the normal position relative to the frame 20 via the positive locking element 48 and the actuator unit 32.

It goes without saying that, alternatively, the coupling openings 46 and the associated knobs can also be omitted. Instead of the U-shaped positive locking element 48 then a likewise U-shaped clamping element is used, which is clamped on the coupling section 44, ie is non-positively connected to the blocking element 26 in the area of the coupling section 44. Such a clamping element can be fastened to the actuator unit 32 in a form-fitting or non-positive manner.

The head section 42 further comprises an incision zone 50.

In the illustrated embodiment, the incision zone 50 is characterized by a two-row pattern of through openings 52. For the sake of clarity, there are in the

Figures only provide some of the through openings 52 with a reference number.

By means of the through openings 52, the material of the head section 42 is specifically weakened in the area of the incision zone 50, so that after the emergency brake unit 24 is triggered, the saw blade 12 cuts into the head section 42 gently and over as large an area as possible.

This results in a reliable coupling between the saw blade 12 and the blocking element 26, which is necessary for reliably braking the rotation of the saw blade 12.

A connection zone 54 is provided essentially between the coupling section 44 and the incision zone 50.

In the embodiment shown, the connection zone 54 also includes through openings 56. Again, for better clarity, only some of the through openings 56 are provided with a reference number in the figures. However, the diameters of the through openings 56 of the connection zone 54 are chosen to be significantly larger than the diameters of the through openings 52 of the incision zone 50.

The connection zone 54 serves, on the one hand, to transmit an actuating force from the coupling section 44 into the incision zone 50. On the other hand, the incision zone 50 is coupled to the deformation section to be explained below via the connection zone 54.

In this context, the through openings 56 of the connection zone 54 serve to ensure sufficient rigidity of the connection zone 54 with the lowest possible mass and thus the lowest possible mass inertia.

In addition, the head section 42 is equipped with a guide surface 58.

The guide surface 58 rests on a guide counter surface 60 of the guide element 36.

Due to the geometry of the head section 42 and the guide counter surface 60, the head section 42 is subjected to a force in the direction of the saw blade 12 when it is shown in the illustration Figure 4 is moved clockwise along the circumferential direction U of the saw blade 12. For this purpose, the guide surface 58 has a normal with an extension component radially outwards.

As is clear from the above explanations, through openings are used in the head section 42 shown in the figures in order to create areas of different rigidity and different resistance to cutting by the saw blade 12. It goes without saying that, as an alternative to the through openings, this can also be achieved by providing different materials in the different areas of the head section 42. In this context, it may be particularly important to use materials of different ductility.

Lying between the head section 42 and the bearing section 38, the blocking element 26 comprises a deformation section 64.

The deformation section 64 connects the bearing section 38 and the head section 42 with each other.

The deformation section 64 is arcuate overall, in the exemplary embodiment shown it is arcuate.

An arc circumferential direction 66, ie the curved longitudinal extension direction of the arcuate deformation section 64, runs essentially parallel to the circumferential direction U of the saw blade 12.

In the illustrated embodiment, an outer circumference of the saw blade 12 and the arcuate deformation section 64 also run concentrically, with the central axis A representing the center.

The deformation section 64 extends in the in Figure 4 illustrated embodiment over a section of the arc circumferential direction 66 with a center angle of approximately 60 degrees.

The circumferential extent of the deformation section 64 is therefore essentially twice the circumferential extent of the head section 42. The head section 42 is therefore circumferentially shorter than the deformation section 64.

Also with regard to a circumferential extent of the bearing section 38, the deformation section 64 is many times longer.

In addition, the deformation section 64 is further spaced from the outer circumference of the saw blade 12 in a radial direction with respect to the central axis A of the saw blade 12 than the head section 42 and the bearing section 38.

In other words, both the head section 42 and the bearing section 38 project radially inwards with respect to the arc circumferential direction 66 relative to the deformation section 64.

In this context, the radial distance D of the deformation section 64 from the saw blade 12 is selected so that it is greater than zero in all operating situations of the emergency braking unit 24. This also applies in particular to an end position of the blocking element 26, which will be explained later.

In other words, the distance D of the deformation section 64 is selected so that it does not contact the outer circumference of the saw blade 12 in any operating situation.

The deformation section 64 further comprises a structure 68 which is plastically deformable in the arc circumferential direction 66.

In the in the Figure 4 In the embodiment shown, this structure 68 is formed from a total of eleven ring segments 70.

The ring segments 70 are arranged adjacently along the arc circumferential direction 66 with a slight overlap.

Each of the ring segments 70 has a wall 72 with a substantially constant wall thickness t.

The walls 72 each define an axially continuous cavity 74.

For the sake of clarity, only some of the ring segments 70 as well as only some of the walls 72 and some of the cavities 74 are provided with a reference number in the figures.

The structure 68, which is plastically deformable in the arc circumferential direction 66, therefore comprises a total of eleven cavities 74 arranged adjacently along the arc circumferential direction 66.

Due to the slight overlap of the ring segments 70, a crescent-shaped cross section results for each cavity 74.

Furthermore, a filling material 76 is arranged in each of the three cavities 74 that are arranged adjacent to the bearing section 38.

In the embodiment shown, the filling material is a rubber material.

Furthermore, the blocking element 26 is made of an aluminum alloy.

The filling material 76 results in a different stiffness of the deformation section 64 in the area of the cavities 74 provided with the filling material 76 than in the area of the unfilled cavities 74. The deformation section 64 therefore comprises two areas with different stiffnesses or, more generally, a stiffness curve.

It goes without saying that the rigidity can be specifically adjusted by appropriate selection of the filling material 76 as well as the number and position of the cavities 74 filled with the filling material 76.

Overall, the structure 68 causes a rigidity of the deformation section 64 along the arc circumferential direction 66 to be smaller than a rigidity of the head section 42.

In addition, the structure 68 has target deformation points 78. These are located in the in Figure 4 illustrated embodiment in each of the sections of the ring segments 70 that project radially furthest inwards and radially furthest outwards.

For the sake of clarity, only some of the target deformation points 78 are provided with a reference number in the figures.

The deformation section 64 is therefore designed to be plastically shortened along the arc circumferential direction 66 in order to brake the saw blade 12. This will be explained below using the Figures 5 to 8 explained.

In this context the shows Figure 5 the emergency brake unit 24 and in particular the blocking element 26 in the normal position already described. This means that the actuator unit 32 has not yet been actuated to effect emergency braking.

Accordingly, no force acts on the blocking element 26 (cf. Figure 9 ).

As has already been explained, the blocking element 26 is held in the normal position via the positive locking element 48 and the actuator unit 32.

The position Figure 5 corresponds to the situation at 0 milliseconds in the diagram Figure 9 .

It is now assumed that the emergency brake unit 24 is triggered at zero milliseconds (0 ms). This results in the actuator unit 32 being actuated and the head section 42 being acted upon in the direction of the saw blade 12. In the exemplary embodiment shown, this is done via the positive locking element 48.

It is understood that the drive motor M is deactivated and/or decoupled from the drive shaft 22 at the same time.

In Figure 6 A situation is shown that arises one millisecond (1ms) after the trigger. Again the situation can be in Figure 6 the force curve at 1ms in the Figure 9 be assigned.

In this situation, the saw blade 12 has cut into the incision zone 50, so that a force coupling between the saw blade 12 and the blocking element 26 has arisen. Due to the clockwise rotation of the saw blade 12, the in Figure 6 At the time shown, the head section 42 already differs from the initial situation Figure 5 taken along a certain circumferential distance along the circumferential direction U of the saw blade 12.

This resulted in the connection between the positive locking element 48 and the actuator unit 32 being released.

The coupling between the form-fitting element 48 and the head section 42 has remained in place in the present case.

It is understood that, alternatively, the connection between the positive locking element 48 and the head section 42 can be separated and the connection between the positive locking element 48 and the actuator unit 32 can be maintained.

In this context, the guide element 36 ensures that the blocking element 26 cannot escape being driven by the saw blade 12 either in the radial direction or in the axial direction. The blocking element 26 is therefore guided along the guide direction F by means of the guide element 36.

The entrainment by the saw blade 12 also caused at least those three ring segments 70 that are arranged adjacent to the head section 42 to be deformed.

More precisely, these ring segments were compressed along the arc circumferential direction 66.

In the Figure 7 the emergency brake unit 24 is shown after another millisecond has elapsed, ie 2 milliseconds after triggering.

The head section 42 is still coupled to the saw blade 12.

However, all ring segments 70 are now compressed along the arc circumferential direction 66, so that the deformation section 64 is already significantly shortened plastically along the arc circumferential direction 66.

The kinetic energy of the rotation of the saw blade 12 is converted into the plastic shortening of the deformation section 64 in order to brake the saw blade 12.

Figure 8 the emergency brake unit 24 shows five milliseconds (5ms) after activation. At this point in time, the saw blade 12 is essentially stationary, ie it no longer rotates.

The deformation section 64 is now essentially completely compressed, i.e. the cavities 74 are essentially closed by pushing the deformation section 64 together along the arc circumferential direction 66.

The Figure 8 shows the emergency braking unit 24 at the end of an emergency braking process. The associated position of the blocking element 26 is also referred to as the end position.

In order to be able to put the emergency brake unit 24 and the sawing device 10 into operation again, i.e. in order to make a sawing device 10 whose emergency brake unit 24 has been triggered ready for use again, the blocking element 26 must now be replaced.

For this purpose, the blocking element 26 can optionally be removed from the frame 20 separately from the actuator unit 32. The blocking element 26 can therefore be dismantled in a single manner. This will be in conjunction with Figure 10 explained.

As already mentioned, the blocking element 26 is rotatably mounted on the frame 20 via the fixed bearing pin 30.

So that the blocking element 26 cannot be separated from the bearing pin along an axial direction of the bearing pin 30, a holding element 80 for holding the blocking element 26 on the bearing pin 30 is provided.

In the illustrated embodiment, this holding element 80 is a side wall section of the guide element 36, ie a section of a wall of the guide element 36, which prevents axial displacement of the blocking element 26.

When the guide element 36 is in its in Figure 10 is the operating position shown in dashed lines, the blocking element 26 is consequently held on the bearing pin 30.

The guide element 36 is rotatably mounted on the frame 20 via a further bearing element 82, which is also designed as a bearing pin.

This allows the guide element 36 to be moved into a release position for dismantling the blocking element 26, which is in the Figure 10 is shown with solid lines. In the release position, the holding element 80 is removed from the bearing element, ie from the bearing pin 30.

So that the guide element 36 does not undesirably assume the release position, it can be locked in the operating position by means of a locking mechanism 84 (see next to Figure 10 also Figure 3 ).

The locking mechanism 84 includes a first through opening 86 on the guide element 36 and a second through opening 88 on the frame 20.

Furthermore, the locking mechanism 84 has a locking pin 90.

The locking pin 90 is equipped with locking wings 92 at a first end and with an operating lever 93 at a second end opposite the first end.

The locking pin 90 can thus be inserted into the through openings 86 and 88 and moved into a rotational position by means of the operating lever 93, in which the locking wings 92 engage behind a section of the frame 20.

In another rotational position, the gripping behind is released so that the locking pin can be pulled axially out of the through openings 86 and 88.

By means of the locking mechanism 84, the guide element 36 can be selectively locked to the frame 20 and optionally unlocked from the frame 20. This of course also applies to the holding element 80 formed by the guide element 36.

No tools are required to operate the locking pin 90 and thus to dismantle the blocking element 26.

To individually dismantle the blocking element 26, only the locking pin 90 is unlocked and removed from the frame 20. The guide element 36 is then moved into the release position and the blocking element 26 is pulled off the bearing bolt 30 along an axial direction, i.e. dismantled from the frame.

An unused blocking element 26 is subsequently mounted.

For this purpose, the bearing section 38 of the unused blocking element 26 is placed on the fixed bearing pin 30.

Furthermore, the unused blocking element 26 is coupled to the actuator unit 32.

Then the guide element 36 is moved back into the operating position and locked there by means of the locking pin 90.

In addition, the actuator unit 32 must be returned to its initial position. This can be done using the control unit 34.

Now the sawing device 10 is ready for operation again and the emergency brake unit 24 is ready for use again.

At the in the Figures 1 to 10 In the emergency brake unit 24 shown, the head section 42 is always both selectively brought into engagement with the saw blade 12 by the actuator unit 32 and held in the normal position by the actuator unit 32 in such a way that the head section 42 does not inadvertently come into contact with the saw blade 12.

In the Figures 11 to 14 Alternatives for locking the blocking element 26 in the normal position are shown. As usual, the force is applied via a pressure piece coupled to the lifting magnet of the actuator unit 32, which is designed to apply an actuating force to the head section 42 in the direction of the saw blade 12. The pressure piece can be designed as a plunger.

In this context, the alternative is as follows Figure 11 the blocking element 26 is held in the normal position by means of a spring-loaded pin 94. For this purpose, the spring-loaded pin 94 engages in an associated recess 96 on a circumferential end face of the blocking element 26.

The actuator unit 32 corresponds to the actuator unit 32 of the embodiment from the Figures 1 to 10 . If this is triggered, it presses the blocking element 26 in the direction of the saw blade 12. As a result, the pin 94 is pressed out of the recess 96 against the spring force.

In the alternative according to Figure 12 a magnet 98 and a counterpart 100 made of ferromagnetic material are provided. In the example shown, the magnet is attached to the guide element 36 and the counterpart 100 to the head section 42 of the blocking element 26.

The pairing of magnet 98 and counterpart 100 is selected such that the head section 42 and thus the counterpart 100 can be detached from the magnet 98 against a magnetic force by means of the actuator unit 32 when the emergency brake unit 24 is actuated.

In the alternative according to Figure 13 is a leaf spring element 102 attached to the frame 20 via a first end. A second end of the leaf spring element 102 is accommodated in a recess 104 which is arranged on the front side of the blocking element 26. This keeps the blocking element 26 in the normal position.

The actuator unit 32 again corresponds to the actuator unit 32 of the embodiment from the

Figures 1 to 10 . If this is triggered, it presses the blocking element 26 towards the saw blade 12. This deforms the leaf spring element 102 so that its free end jumps out of the recess 104 and releases the blocking element.

With the alternative Figure 14 Two balls 106, 108 are provided, each of which engages at different ends of one of the coupling openings 46.

The balls 106, 108 are spring-loaded so that they can be pushed out of the coupling openings 46 when the actuator unit 32 is actuated and can thus release the blocking element 26.

The Figure 15 shows sections of an alternative sawing device 10.

In the following, only the differences to the sawing devices 10 already explained will be discussed. Identical or corresponding elements are given the same reference numbers.

The differences concern the blocking element 26.

Unlike in the previous embodiments, the deformation section 64 now includes hexagonal ring segments 70. This means that the walls of the 72 of the ring segments 70 each form hexagons and the through openings 74 defined by these walls 72 each have a hexagonal cross section.

Another difference is that two radially adjacent rows of ring segments 70 are now provided. Each of these rows of ring segments 70 also has 16 ring segments 70. There are therefore more ring segments 70 provided in each row than, for example, in the blocking element 26 Figure 4 .

The plastically deformable structure 68 of the blocking element 26 Figure 15 can also be referred to as a honeycomb structure.

For the sake of clarity, only some of the ring segments 70 as well as only some of the walls 72 and some of the cavities 74 are provided with a reference number.

The target deformation points 78 are now formed by those sections of the walls 72 of each ring segment 70 which include the corner of the hexagonal cross-section that projects radially furthest inward and the corner of the hexagonal cross-section that projects radially furthest outward.

Each ring segment 70 therefore comprises two target deformation points 78, one radially inner and one radially outer.

The through openings in the head section 42, more precisely the through openings 56 in the connection zone 54, now also have hexagonal cross sections. In addition, they are arranged slightly differently than in the blocking element 26 Figure 4 .

Another alternative sawing device 10 shows sections Figure 16 .

Again, only the differences from the previous embodiments are explained.

The sawing device 10 off Figure 16 has a significantly smaller saw blade 12 than the previously explained sawing devices.

The blocking element 26 does not differ from the blocking element 26 in terms of its shape Figure 10 . It was only scaled proportionally.

This can be done in particular by comparing the size between the blocking element 26 and the actuator unit 32, which is in the embodiments according to Figures 10 and 16 is identical.

Another alternative sawing device 10 shows sections Figure 17 .

Again, only the differences from the previous embodiments will be discussed. These again concern the blocking element 26.

In the embodiment according to Figure 17 the head section 42 of the blocking element 26 is designed differently.

On the one hand, its front side is no longer pointed, but rather blunt.

On the other hand, compared to the previous head sections 42, this is longer along the arc circumferential direction 66.

This also entails an increased number and changes in the size and position of the through holes 56 in the connection section 54.

After the total length of the blocking element 26 along the arc circumferential direction 66 has remained the same, the deformation section 64 is now made shorter. This now includes only a total of seven ring segments 70. The wall thickness t of the associated walls 72 was compared to the embodiment according to Figure 4 enlarged.

For the sake of clarity, only some of the ring segments 70 as well as only some of the walls 72 and some of the cavities 74 are provided with a reference number.

An additional embodiment of a sawing device 10 shows Figure 18 .

The sawing device 10 is now designed as a table saw.

Otherwise, particularly with regard to the emergency brake unit 24, the above explanations apply in an analogous manner.

It is noted that in all of the aforementioned embodiments, the actuator unit 32 can also be individually removable from the frame 20. This serves to easily repair the emergency brake unit 24 in the event that a defect occurs in the actuator unit 32.

The actuator unit 32 can also be dismantled without tools.

Reference symbol list

10

Sawing device

12

saw blade

14

Basic assembly

16

Arm assembly

18

Support surface

20

Frame

22

drive shaft

24

Emergency braking unit

26

Blocking element

28

Bearing element

30

bearing pin

32

Actuator unit

34

Control unit

36

Leadership element

38

Storage section

40

Warehouse opening

41

wall

42

Head section

44

coupling section

46

Coupling openings

48

Positive locking element

50

incision zone

52

Passage opening

54

Connection zone

56

Passage opening

58

Guide surface

60

Guide counter surface

64

deformation section

66

Arc circumferential direction

68

plastically deformable structure

70

Ring segment

72

Wall

74

cavity

76

filling material

78

Target deformation point

80

Holding element

82

Bearing element

84

Locking mechanism

86

first passage opening

88

second passage opening

90

Locking pin

92

Locking wings

93

Control lever

94

Pen

96

deepening

98

magnet

100

counterpart

102

Leaf spring element

104

deepening

106

Bullet

108

Bullet

A

Central axis of the saw blade

D

Radial distance of the deformation section from the saw blade

M

drive motor

U

Circumferential direction of the saw blade

F

Direction of leadership

G

Area for a housing part, not shown

t

Wall thickness

Claims (15)

Sawing device (10) with a frame (20), a circular disk-shaped saw blade (12) which is rotatably mounted with respect to the frame (20) and an emergency brake unit (24), the emergency brake unit (24) having a blocking element (26), an actuator unit ( 32) and a control unit (34), which is integrally formed with the actuator unit (32) or is coupled to the actuator unit (32) in terms of signals, wherein the blocking element (26) has a bearing section (38) via which the blocking element (26) is mounted on the frame (20), and comprises a head section (42) which is designed to selectively engage in the saw blade (12) for braking, wherein the actuator unit (32) is coupled to the blocking element (26) at least in a normal position of the blocking element (26) in such a way that the blocking element (26) can be selectively brought into engagement with the saw blade (12) by means of the actuator unit (32), and wherein the blocking element (26) can be dismantled from the frame (20) either separately from the actuator unit (32) and/or separately from the control unit (34). Sawing device (10) according to claim 1, comprising a guide element (36) for guiding the blocking element (26) at least along a guide direction (F), which runs at least in sections parallel to a circumferential direction (U) of the saw blade (12). Sawing device (10) according to claim 1 or 2, wherein the blocking element (26) is connected to the frame (20) via a bearing element, the bearing element being singularly removable from the sawing device (10). Sawing device (10) according to claim 3, comprising a locking mechanism by means of which the bearing element can be selectively locked to the frame (20) and selectively unlocked from the frame (20). Sawing device (10) according to claim 2 and claim 3 or 4, wherein the guide element (36) is mounted on the frame (20) by means of the bearing element. Sawing device (10) according to claim 1 or 2, wherein the blocking element (26) is mounted on the frame (20) by means of a fixed bearing element (28) and a holding element (80) for holding the blocking element (26) on the bearing element (28) is provided . Sawing device (10) according to claim 6, wherein the holding element (80) can optionally be individually dismantled from the bearing element (28). Sawing device (10) according to claim 2 and claim 6 or 7, wherein the holding element (80) is formed by a portion of the guide element (36). Sawing device (10) according to one of the preceding claims, wherein the blocking element (26) comprises a coupling section (44) via which the blocking element (26) is coupled to the actuator unit (32) at least in the normal position, the coupling section (44). is positioned at an end of the blocking element (26) opposite the bearing section (38). Sawing device (10) according to one of the preceding claims, wherein in an end position the blocking element (26) is decoupled from at least a section of the actuator unit (32). Sawing device (10) according to one of the preceding claims, wherein the blocking element (26) comprises a deformation section (64) which lies between the bearing section (38) and the head section (42) and / or the bearing section (38) and the head section (42 ) connects with each other,
wherein the deformation section (64) is arcuate and is designed to be plastically shortened along an arc circumferential direction (66) in order to brake the saw blade (12). Method for making a triggered emergency brake unit (24) of a sawing device (10) ready for use, wherein the sawing device (10) comprises a circular disk-shaped saw blade (12) and the emergency brake unit (24) has a blocking element (26) which is designed to optionally be inserted into the saw blade (12) to intervene to brake the saw blade (12), the method comprising the following steps: - Dismantling the blocking element (26) separately from an actuator unit (32) of the emergency brake unit (24) and/or separately from a control unit (34) of the emergency brake unit (24), the blocking element (26) engaging in or with the saw blade (12). the saw blade (12) was engaged, - Mount an unused blocking element (26). Method according to claim 12, wherein when assembling the unused blocking element (26), the unused blocking element (26) is coupled to an actuator unit (32) of the emergency brake unit (24). Method according to claim 12 or 13, wherein to dismantle the blocking element (26), a bearing element (28), by means of which the blocking element is mounted in the sawing device (10), is dismantled, or a holding element (80) from a fixed bearing element (28) , by means of which the blocking element (26) is stored in the sawing device (10), is removed. The method of claim 14, wherein the retaining member (80) is formed by a portion of a guide member (36), and removing the retaining member (80) from the fixed bearing member (28) includes moving the guide member (36) to a release position.

Images