DE9301011U1 - Knife clamp clamping system modular - Google Patents

Description

20.01.93

Martin Kohl

Birkenfelder Str. 10, 7538 Keltern - Dietlingen

KNIFE CLAMPING SYSTEM MODULAR

The innovation concerns a workpiece clamping system consisting of a clamping block with clamping screw and associated clamping knives of various lengths, groove stops and support plates.

The low-clamping flat clamping system according to the invention, which hereinafter will be called MKSS-Mod.-Knife-Clamping-System-Modular, has the task and area of application on milling machines, drilling machines, machining centers, planing machines or other machines of this type which are equipped with a modular grid clamping system to ensure simple but effective clamping - with good frictional connection - of workpieces for processing.

With the MKSS, parts such as plates, strips or all machine parts whose thickness must be machined flat on vertical processing machines are clamped to the machine table (A).

It is irrelevant how wide and long the parts to be clamped are, assuming that the long side is along the stops, it is only a question of how many clamping elements - stops and clamping blocks - are used, the part to be machined must not be higher than the width due to the leverage effect.

The function and advantages of the MKSS mod. will be illustrated using an example.

Assuming that we have a clamping table of 800 x 3000 mm .

First we want to machine a strip (C) of 20 x 50 x 2500 mm to the thickness (dimension 20), we insert e.g. 4 groove stops into the grid hole (D), here we attach our strip, support the unevenness between the table and the strip at the point where we want to clamp, now we insert the clamping block with the clamping screws into the grid in front of it exactly opposite the groove stops, place the clamping knives on the support plates against the strip and clamp the clamping knives against the workpiece with the clamping screw.

Since we clamp almost horizontally against the groove stops Fig.2, with only one-sided pressure on the machine table, distortion of the bar is almost impossible.

After processing, the bar is turned over and tightened again in exactly the same way.

Another option is to machine a plate on the same table, e.g. 600 x 30 x 2500 mm. We place the plate on the table width between 2 grid rows of holes if we are on the length of 2500 mm

If we want to clamp it 4 times, we support the raw plate again in 8 places, now we place clamping blocks with clamping screws in the next free grid holes at all 8 points, place our clamping knives on the support plates against the plate again and place the clamping screw against the clamping knives and now tighten all the clamping screws evenly against each other Fig.l.

However, with this clamping there is a greater risk of warping thin plates, so it is better to clamp the 1st side according to the 1st variant and to clamp it from both sides when machining the 2nd side (Fig. 2), as the workpiece is clamped directly on the table without any problems, i.e. the plate or strip is as plane-parallel as the clamping table. In addition to these advantages, there is also the fact that the workpiece surface is free of clamping devices and does not hinder machining, that clamping can always be done from the short workpiece side, that the workpiece length plays no role at all, theoretically this could be infinite, only a corresponding number of clamping points must be determined. The same applies to unstable long workpieces, these can also be machined without problems if the clamping points are arranged closer together.

A key factor of the MKSS-Mod. is the time savings during clamping, due to fewer parts and optimal handling of the entire system.

There is no need for a large number of conventional clamping screws, clamps and clamping supports, which then cover the workpiece during machining and thus get in the way.

The design description of the MKSS knife clamping system mod. set, the set contains basic equipment which is sufficient for shorter workpieces and consists of 4 clamping blocks/clamping blocks with clamping screws, 2 stops, 3 x 2 clamping knives of different lengths each, 4 base plates, 8 centering pieces, 8 fastening screws Din 912.

All parts are made of high-quality structural steel, depending on the type of use, partially and also contour-hardened or tempered, clamping knives are also made of non-ferrous metal or plastic if this is necessary due to damage to the workpiece.

All steel parts are burnished.

The clamping block/tension block (1) has a height (a) of 45 - 50 mm, while (b) remains at 18 mm and the angle alpha at 10 degrees. The dimension for (c) is variable, this changes according to the grid dimension (e), whereby (d) remains at 30 mm. The hole (f) has a diameter of 16 or 22 mm + 0.10 mm according to the mounting holes on the grid plate, if necessary this must also be changed. For grid 40, (f) is 16 mm, for grid 50, (f) is 22 mm. The dimension (g) is 16 mm.

The dimension (i) depends on the fastening screw Din, with M16 being used for (f) 22 and M12 for (f) 16. The thread (h) corresponds to the force required, so M16 is used.

Part (2) slot stop is a base body where (a) is based on the dimension (c) of part (1), (b) is 40 but now (c) is 30 mm. The dimension (f/g/i) is based on the same sizes as part (1), since these are built together on the same grid plate.

The groove stop can be set off at the side with a staircase to reduce the stop height. The groove stop (2) is hardened or tempered.

The clamping knife parts (3 and 4 and 5) have the same dimensions (a/b/c). The radius (d) is required so that the clamping screw (6), which also has the same radius (c), can slide like a ball and socket, so that they can absorb the forces of the changing angles that arise when clamping by adjusting the clamping screw.

For the clamping screws M16, (c) is R7.

The set includes 3 types of clamping knives, with (e) varying from 25 mm for the smallest to 50 mm and 80 mm. The dimension (f and angle alpha) vary for the part (3,4,5) according to the required design, the dimension (g) depth of the pan corresponds to 1/2 radius (d).

A hexagon screw DIN 933, 12.9 is used for the clamping screw (6), whereby the radius (c) is machined accordingly, (a) corresponds to the thread in the clamping block (1) and (b) of part (6) depends on the table path width, but is approx. 60 - 90 mm long.

The support plates (9) are insignificant in terms of size; they are only intended to keep the clamping knives away from the table to prevent damage - and to clamp workpieces slightly higher when mounted underneath.
A flat steel of (a) 30 (b) 10 (c) 5 is used.

The centering bush part (8) has the function of locking the clamping block (1) on the grid plate so that the clamping pressure does not go to the fastening screws. Since part (8) has the same diameter (a) as the respective clamping block at (f) and also the grid plate, a direct shearing effect is created, i.e. maximum force absorption. The inner dimension (b) is thread M12 or M16 accordingly for the clamping block (i). The dimension (c) is 15 mm so that the centering bush can be countersunk in the hole (f/g). This is necessary if part (8) is glued to the fastening screw if necessary so that part (1/8) and the clamping screw form a unit.

In this case, assembly is carried out in such a way that the centering piece protrudes 6 mm from the clamping block when the fastening screw is tightened.

As already mentioned, different nominal sizes are built, so the essential designation for part (1) is size (e), because this defines the grid.

For example, the designation MKSS Type 40-Mod. stands for a knife clamping system set for a modular clamping plate with a 40 mm grid.

Finally, all dimensional variations should be considered and assessed in this clamping system with small and large clamping blocks with clamping knives, also in other variants protected.

What is worthy of protection is the fact with which arrangement and which components the workpieces are clamped.

Dimensional changes and further developments are included in the protection, this applies to the system as well as to all individual parts.

Claims (6)

14.10.92 Martin Kohle Birkenfelder Str. 10, 7538 Keltern - Dietlingen Knife clamping system modular PROTECTION CLAIMS 1. Modular knife clamping system consisting of clamping jaws with clamping screws, clamping knives, stops, support plates and centering bushes. The clamping blocks are designed so that they can be attached to the clamping table machine table with two fastening screws with DIN 912 screws, whereby the centering bushes (10) for the locking between the clamping block and the machine table are inserted into the centering holes provided for this purpose. These centering holes are on the same axis as the fastening screws. In the clamping block (1) there is a thread at an angle of 10 degrees for the clamping screw (6) with which the clamping knives (3/4/5) are pressed against the workpiece to be clamped. The clamping knives (3/4/5) have different lengths, for the pressure absorption from the clamping screw with a pan, the clamping screw with a ball (2). The clamping knives are tapered towards the workpiece system and have a ball there (h) this means that the angle of attack can be variable. The stop (2) has the same fastening as the clamping block. The stop is asymmetrical with a small overall height. The support plates (7) are made of flat steel and are required as a support under the clamping knives so that they press onto the workpiece slightly above the table. The workpieces can be clamped either via the clamping block against the stop, or on both sides with clamping blocks, whereby the clamping screw belongs to the clamping blocks. 2. Modular knife clamping system according to claim 1, characterized in that that if relatively large space is required between the workpiece and the clamping block, the clamping knives (3,4,5) are extended in length (e) and, if necessary, the set is supplemented with longer knives. 3. Modular knife clamping system according to claim 1, characterized in that that the clamping system is retained as in (Fig. 1) that the workpieces are clamped against each other from both sides using clamping blocks (1) and clamping knives (3/4/5), or as in (Fig. 2) that the workpieces are clamped against the stops (2) from one side using clamping blocks (1) and clamping knives (3/4/5). The individual components can change in their dimensions and design if this is required by the clamping force and the design. 4. Knife clamping system modular according to claim 1 characterized in that in the clamping block (1) on the flange side there are 2 holes at a distance of the respective grid dimension and corresponding diameter for the locking. These holes have a diameter 0.1-0.2 mm larger than the nominal size of the centering bushes (10) 5. Modular knife clamping system according to claim 1 characterized in that the locking holes in the clamping block are deep enough that the centering bushes (10) can be countersunk. This is necessary if the centering bushes (10) are attached to the fastening screw (8) by gluing. Alternatively, the centering bushings can also be supplied loose. 6. Modular knife clamping system according to claim 1 characterized in that the stop (2) has 2 holes on the flange side at a distance from the respective grid dimension and corresponding diameter for locking. These holes have a diameter 0.1-0.2 mm larger than the nominal dimension of the centering bushes (10)