Attachment on a bench or sizing saw

(42) Date of commencement of the patent: 15. 8.1998 (45) Date of issue: 25. 3.1999 (51) Int.Cl.⁶ : B27G 19/02

<td>(30) Priority:</td><td>(73) Patent owner:</td>

<td>18. 5.1993 OE 4316586 claims. (56) Documents:</td><td>OTTO MARTIN MASCHItCNBAU GMBH &amp; CO. D-87720 OTTOBEUREN (DE).</td>

<td>CH 680347A DE 2631767B DE 3345335A EP 489397A</td><td></td>

<td>US 4033218A US 4214493A US 4614140A US 4875398A US 5181447A</td><td></td>

(54) DEVICE ON TABLE OXER FORMAT EXTRACTION MACHINES (57) The protective cover (4) intended to completely or substantially cover the saw blade (6) is supported by an arm (1) made up of rectangular tubes. This arm (1) also forms a suction channel. Through the cross guide (3), the arm and thus the guard can be moved well. By switches or sensors ensures that the protective cover (4) in the working position, the saw blade (6) largely covers.

<img file="AT404917B_D0001.tif" />

CD

AT 404 917 kr eeraas

AT 404 917 Β

The invention relates to a device for table or format sawing machines with a machine frame and a table and an under the table, rotating driven circular saw blade, wherein the saw blade bearing is height adjustable according to the workpiece thickness, and a height-adjustable and adjustable in the axial direction of the saw blade, removable, from a mounted on the machine frame arm guard over the table for at least partial coverage of the circular saw blade.

According to the accident prevention regulations, table or format saw machines must be provided with a protective cover which covers the saw blade completely or at least to a large extent. This is especially true when no workpiece is on the table. When a workpiece is being machined, the protective cover must adequately cover the part of the saw blade which projects upwards over the workpiece.

In US-A 5 181 447 a Sagemaschine is described in which the protective hood is supported by an arm, wherein the arm is designed so that an adjustment of the protective hood to the saw blade is possible. In this construction, the adaptation of the guard to the necessary position by manual adjustment, with appropriate guides between the guard on the one hand and the support arm on the other hand are provided. These elements burden the support arm, which must have a corresponding stable training, if the goal of such an arrangement should really be achieved. If the adaptability is not sufficiently comfortable and easy to operate, the adaptation is omitted and the protective hood can not or only partially fulfill its task.

A particular problem in this context arises from the fact that it is desirable to provide a trigger channel in the area of ​​the guard, which should not hinder the adjustability of the guard.

If a suction duct of conventional construction is used, as can be seen, for example, from EP-A 0 489 397 A1, then the suction duct obstructs the exact adjustment of the protective hood. The suction channel consists for example of an elastic tube, which seeks to adjust the guard, so that in turn must be provided locking means to fix the guard.

US-A 4,033,218 shows only an adjustable guard, but no trigger channel.

The invention has for its object to provide a device that facilitates the correct adjustment of the protective hood substantially or makes the adjustment largely automatic.

The invention relates to a device of the type described above and proposes that the arm is substantially rigid and between the arm and the machine frame a cross guide is provided, which allows the guard the movements of the height direction and in the direction of the axis of rotation of the saw blade , wherein the arm forms a suction channel.

In the invention, the arm can be made substantially rigid, because it requires no adjustment in itself. The cross guide can also be designed stably. The trigger channel is routed inside the arm or is formed by the arm, so that the trigger channel also has no effect on the position of the guard.

It is advantageous hiebei if the arm consists essentially of right angles adjoining sections.

In the invention it is provided that the arm end extends in the saw blade plane. It is advantageous if the arm end carries a displaceable in the blade plane intermediate piece to which the guard is releasably attached. The displaceable intermediate piece makes it possible to adapt the protective cover to the respective conditions, for example, when a scoring blade is used in addition to the main saw blade. The protective cover can then be easily replaced.

The intermediate piece is designed in particular as a box profile, which is part of the suction channel.

After a further mark of the invention, the arm also carries a control panel, which is preferably arranged pivotably. In this way, the arm is transferred to another function. In addition to the holder of the protective hood and to accommodate the suction channel, the arm also carries the controls or Control elements. The pivotal arrangement has the advantage that the control panel is the two usual jobs on a circular saw machine adaptable. These jobs are usually once in the extension of the axis of the circular saw blade and on the other in the plane of the circular saw blade or laterally thereof. By simply swiveling the control panel, the function of the machine can be monitored and controlled from every workstation.

For the formation of the cross guide, the invention proposes in particular that a horizontal, aligned parallel to the saw blade axis, arranged in the machine frame guide is provided with a guide element having at its end a vertical guide for the arm. In particular, the horizontal guide can be stored very well in this way. For the leadership rolls or sliders are generally used, which cooperate with corresponding runways or slideways.

AT 404 917 Β

As already stated, the arm od with appropriate compensation of the weight by counterweights, springs. like. be moved well by hand. The ease of use is increased when motor drives are provided at least for the vertical guidance of the cross guide. Such a motor drive facilitates the correct adjustment of the guard much. A motor drive can be done for example by electric servomotors. But it can also be applied pneumatic or hydraulic means.

A further embodiment of the invention is characterized by means for scanning the altitude of the saw blade bearing, said device then determines the altitude of the protective hood. The altitude of the saw blade bearing can, as is known, be changed by hand-operated means to adjust the relative position of the saw blade in the table of the respective workpiece thickness. This adjustment of the saw blade bearing can be transferred directly to the altitude of the guard, for example, by displacement of the arm in the vertical guidance of the cross guide. In general, however, the setting is done by servomotors or similar means.

According to the invention further controlled by hand or by the workpiece probe means is provided for changing the altitude of the protective hood. The altitude of the guard can for example be determined solely by the altitude of the saw blade storage. In some cases, however, it is also desirable to particularly adjust the distance of the protective hood from the workpiece.

Next, the invention proposes switches or sensors in the table, which report an on-hook workpiece. Such switches or sensors also interact with switches or sensors on the hood which determine the height of the workpiece. Again, these values ​​are used to automatically adjust the guard setting.

Another development provides that switches or sensors are provided on the hood for determining the workpieces in the horizontal direction. Such an arrangement allows an inserted workpiece automatically adjusts the correct altitude of the guard. It is also possible to change the altitude of the saw blade storage mutatis mutandis, so that the device of the invention not only achieved that the protective cover independently occupies the correct altitude, but that almost all the necessary settings of the machine are done automatically.

When talking about switches or sensors, it is understood that any type of sensors or switching elements. The switches or sensors can emit electrical pulses, for example. You can also use pneumatic. Ways become effective. It can also be used optical, ultrasonic or laser switching elements application. The particular advantage of this is that no workpiece contact takes place.

In the drawing, an embodiment of the invention is shown schematically. Show it;

Fig. 1 is a table saw with a device according to the invention and

2 is a side view in the direction of arrow II of FIG. 1st

The machine frame 2 carries the table 15. In the machine frame 2, the saw blade 6 is mounted. The axis of rotation of the saw blade 6 is denoted by 5. In addition to the saw blade 6, a scoring blade 16 can also be provided.

In the machine frame 2, a guide member 13 is mounted, which is supported inter alia on the rollers 17. This guide element is movable in the direction of the double arrow 18. At the rear end 19 of the guide member 13, the vertical guide 14 is provided, so that a cross guide 3 is obtained. The vertical guide 14 guides the arm 1. This arm 1 is constructed of rectangular tubes and composed of the sections 7, 8 and 9. This construction leads to a comparatively rigid structure. At the lower end of the section 7, a suction port 20 is provided. The section 9 carries on its underside the intermediate piece 11, which is constructed of a rectangular tube which is closed at the ends. However, the intermediate piece is connected to the suction channel in the section 9, which is achieved by corresponding recesses in the lower wall of the section 9 and in the upper wall of the intermediate piece 11. The intermediate piece 11 is limitedly displaceable relative to the portion 9, whereby the protective cover 4 can be adjusted in the direction of the double arrow 21. The protective cover 4 itself is removably held on the intermediate piece 11.

The end 10 of the arm also carries the control panel 12 for controlling the machine. This control panel is pivotally mounted. In the position shown, the control panel is assigned to the workplace in extension of the axis 5, ie the workplace before the arrangement shown in FIG. If the control panel 12 is pivoted, it can also be assigned to the workstation in the view shown in FIG.

By the cross guide is the arm 1 and thus the guard 4 both in the direction of

Double arrow 18 in the horizontal direction movable and in the direction of the double arrow 22 in the vertical direction.

AT 404 917 Β

The various switches and sensors according to the invention are not shown in detail in the drawing. The switches or sensors can also be realized by switching strips of mechanical, electrical or pneumatic type on the two undersides of the protective hood 4.

The safety edges of mechanical design actuate when touched from below in a lowering in the direction of the arrow 22 or even when touched by an inserted in the table plane workpiece successively arranged limit switch. With a small actuating travel, a first limit switch is switched, with a larger actuation travel also the second limit switch. If the safety edges are not pressed, the hood 4 moves down against the machine table 15 until the first limit switch is actuated. If a workpiece is now placed and pressed against the protective cover and thus against the safety edge until the second limit switch is actuated, the protective cover moves upwards. The workpiece can be passed under the protective hood. Once the workpiece has been completed, the safety edge is released. The first limit switch comes to rest and the guard moves down. This saw blade guard control ensures that the guard releases the saw blade for work only.