Clamping device and clamping system

Abstract

The invention relates to a clamping device (2) for insertion into a groove (4) of a machine tool table (3) with a gearbox (7), wherein the clamping device (2) has a drive side (2a) and an output side (2b), wherein a motion variable can be introduced on the drive side (2a), wherein the motion variable can be converted into a rotary motion of the output side (2b), wherein a bolt (5) with an external thread is arranged on the output side (2b).

Description

The invention relates to a clamping system according to claim 1 and to a clamping device according to claim 6.CN217193944U discloses an apparatus for milling specially shaped workpieces. The device is fastened on a surface of a machine tool table in order to process the specific workpiece. A bolt is firmly fixed in order to screw on the workpiece.CN214722290U discloses a device which can be mounted on a tool table in order to process a corresponding workpiece sample. A bolt is firmly fixed in order to screw the workpiece sample onto the device.DE 10 2010 044 783 A1 discloses a processing machine.CN 217193944 U discloses a special fixing tool for dumbbell-shaped tension samples of a milling machine.Such devices can have the disadvantage that they are mounted on the tool table, so that space for the device must be used between the workpiece to be machined and the tool table, which reduces the space to be machined for the workpiece sample. In addition, the bolt is firmly fixed, wherein screwing can only be achieved by actively turning the workpiece to be machined onto the bolt.Proceeding from this, it is the object of the present invention to provide an improved clamping device.The object is achieved with a clamping device having the features of claim 6. Advantageous embodiments are described in the dependent claims.In the clamping device of the generic type, it is proposed that a bolt with an external thread be arranged on the output side.The movement variable can be, in particular, a force or a torque. It is advantageous here if the amount of movement that can be introduced is a torque, wherein a rotational movement on the drive side can be converted into the rotational movement of the output side. In this way, the bolt also experiences a rotational movement and can thus be screwed to a workpiece to be machined. The bolt is thus designed to be axially movable about its longitudinal axis, which enables the bolt to be screwed into the workpiece to be machined.The clamping device according to the invention has the advantage that it can be introduced into a machine tool table without requiring space on a contact surface for the contact of a workpiece to be machined, wherein the contact surface is that surface on which the workpiece to be machined is arranged or can contact. The workpiece can thus be screwed directly onto the contact surface by screwing the bolt into the workpiece to be machined, so that no space between the workpiece and the contact surface is blocked by the clamping device. In manufacture, such installation space is often limited. The clamping device according to the invention thus makes it possible to provide more space for the workpiece to be machined, so that, for example, larger workpieces can be used with the same dimensioning of the machine tool table.The screwing to a workpiece to be machined can thus also be effected by the clamping device itself, in that the movement variable of the drive side is converted into a rotational movement variable of the output side. It is conceivable that the movement variable can be introduced from an underside into the drive side. The underside is in particular that side of the clamping device on which the bolt with external thread does not extend out of the clamping device.Furthermore, it is possible to screw any desired workpiece shapes to the clamping device.The clamping device can have a gear mechanism, wherein the drive side and the driven side are arranged on the gear mechanism. Furthermore, the transmission can advantageously be a continuously variable transmission.In this way, for example, a laterally offset drive side can be achieved, as a result of which the movement variable can be converted into the rotational movement of the output side. In this way, for example, the drive side can be located outside the machine tool table, wherein the driven side is introduced into the groove of the machine tool table. In this case, the movement variable can be introduced on the drive side without being impeded by the machine tool table. At least, however, the drive side can be reached more easily by not being blocked by the workpiece to be machined.On the drive side and on the output side, a gearwheel with sprockets can be arranged in each case, wherein the force introduced or the torque introduced can be converted by a closed chain into a longitudinal movement of the closed chain and can subsequently be converted into a rotational movement of the output side.The bearing of the drive side and the driven side can be integrated in particular in a housing of the clamping device. In this case, the housing can have, for example, a cover section and a base section, wherein the cover section and the base section are formed as a plain bearing seat of the chain tension. An efficient gear for the clamping device can thus be provided.Furthermore, the tensioning device can advantageously have a link for tensioning the chain.The chain can be tensioned or released on the transmission in a simple manner via the link. This allows simple installation of the clamping device.The link allows the chain to be tensioned and released on the gears. The link may have a frame, for example, wherein an upper connecting piece and / or a lower connecting piece is connected to the gearwheel of the drive side and / or to the gearwheel of the driven side on the frame. The frame can be fixed or released, for example, by means of screws on a central block of the clamping device, so that the frame is mounted displaceably on or on the central block. If the screws do not hold the frame fixed to the central block, the frame and thus also the gearwheel of the drive side and / or of the driven side connected via the upper connecting piece and / or lower connecting piece can be displaced in the direction of longitudinal extent of the clamping device. The central block and a lower part of the clamping device can be formed in particular in one piece. However, it is also conceivable for the central block and the lower part to consist of separate parts and to be subsequently connected to one another.Thus, the distance between the driving-side and driven-side gears can be shortened and extended, respectively. With a smaller distance between the gears, the chain can be easily inserted. If the spacing of the gearwheels is subsequently increased again via the link, the chain is mounted on the gearwheels in the tensioned state. By means of the displaceable link, the chain can also be released again from the gearwheels of the drive side and the driven side.Furthermore, an elongation of the chain caused by stress, for example, can be compensated, whereby the functionality can also be ensured in the case of an elongated chain.The drive side and the driven side can lie on a common plane.In this way, the clamping device can be made more compact. Due to the position of the drive side and the driven side on a common plane, the clamping device can be designed to be very flat.It is particularly advantageous if the clamping device is configured to be flat. This can be achieved, for example, by the height of the tensioning device being not greater than twice the height of a chain used. The height is the direction in which the bolt extends in its longitudinal extension direction. However, at the height of the clamping device, the height of the bolt with external thread is not taken into consideration.The length of the clamping device can be variable in this case by the length being adapted to the machine tool table used, for example. The length is the direction in which the clamping device can be inserted into the groove of the machine tool table.The bolt can be mounted in the clamping device by means of a slide bearing.By selecting a suitable sliding bearing, the axial movability of the bolt can be ensured.The present invention further relates to a clamping system having a machine tool table with a contact surface for the contact of a workpiece to be machined and with at least one groove, wherein at least one clamping device described above is introduced into the groove, wherein the bolt with an external thread protrudes from the contact surface of the machine tool table, wherein a workpiece to be machined can be screwed onto the external thread.The clamping system has the advantage that the clamping device can be introduced into the machine tool table without requiring space on the contact surface for contact with the workpiece to be machined. The workpiece can thus be screwed directly onto the contact surface, so that no space between the workpiece and the contact surface is blocked by the clamping device.The groove may be a T-shaped groove. The T-shaped groove achieves simple positioning of the clamping device in the machine tool table in that the clamping device can only be inserted into the T-shaped groove in one direction of movement.The groove can be designed in particular such that it is dimensioned larger than the clamping device, wherein the clamping device is movably mounted in the groove.The clamping device can be arranged in the groove in particular on the side of the machine tool table facing away from the contact surface, wherein the bolt protrudes through the groove onto the side of the machine tool table facing the contact surface. In this way, only the bolt of the clamping device projects through the groove onto the side of the machine tool table facing the contact surface. The bolt can be screwed into the workpiece to be machined without additional installation space being taken up between the workpiece and the machine tool table by the clamping device. The bolt can thus be screwed into the workpiece to be machined by the clamping device.In particular when using a plurality of clamping devices and a workpiece to be machined, the workpiece cannot be screwed onto the bolts of the clamping devices. The screwing is then effected via the clamping device itself by introducing a movement variable on the drive side and converting this into a rotational movement of the bolt.The screwing to a workpiece to be machined can thus also be effected by the clamping device itself, in that the movement variable of the drive side is converted into a rotational movement variable of the output side. In this case, the movement variable is introduced into the clamping device in particular on the side of the machine tool table facing away from the contact surface. The movement variable can be introduced at the drive side, for example, in that a torque can be introduced through the groove with a suitable tool, for example. It is also conceivable for the drive side to protrude laterally from the machine tool table, for example, while the output side is arranged in the groove of the machine tool table. In this way, a corresponding movement variable can be introduced in a simple manner on the drive side of the clamping device. The drive side is arranged below the contact surface and on the side of the machine tool table facing away from the contact surface,The clamping device can be fixed to the machine tool table by screwing to the workpiece. Furthermore, the clamping device can advantageously be mounted movably in the groove and can only be fixed to the machine tool table by screwing to the workpiece.The clamping device is thus fixed in the groove solely by the screw connection. This has the advantage that the clamping device is freely movable in the groove before assembly with the workpiece and can be pushed to the desired position in the groove. The clamping device can then be fixed to the machine tool table by screwing to the workpiece.The indefinite term "a" is to be understood as such and not as a number word. It is thus also conceivable for a multiplicity of clamping devices, in particular two or four clamping devices, to be arranged in the clamping system. In this way, larger workpieces can be screwed to a plurality of clamping devices.The invention is explained in more detail below by way of example with reference to exemplary embodiments with the accompanying drawings. The following are shown: FIG. 1 shows a clamping system according to the invention with a clamping device in a first embodiment; FIG. 2 is an enlarged detail of the clamping system according to FIG. 1 ; FIG. 3 shows a clamping device according to the invention in a perspective view for a clamping system according to FIGS. 1 and 2 ; FIG. 4 shows the clamping device according to FIG. 3 in a rotated perspective view; FIG. 5 shows the tensioning device according to FIG. 3 without illustration of the chain; FIG. 6 shows a driven side with bolts of a clamping device according to FIGS. 3 to 5 in a schematic side view; FIG. 7 shows a schematic illustration of a clamping system according to the invention in a side view with a workpiece to be machined.FIG. 1 shows a clamping system 1 according to the invention with a clamping device 2 in a first embodiment. The clamping system 1 has a round machine tool table 3 with a plurality of T-shaped grooves 4. The invention is also not limited to a single clamping device 2. It is thus conceivable that a plurality of clamping devices 2, in particular two or four clamping devices 2, can also be introduced into the T-shaped grooves 4.FIG. 2 shows an enlarged detail of the clamping system 1 according to FIG. 1. The clamping device 2 has a drive side 2 aand an output side 2 b, wherein a movement variable can be introduced on the drive side 2 awhich is converted into a rotational movement of the output side 2 b. On the output side 2 b, a bolt 5 with an external thread is arranged.It is clear from FIGS. 1 and 2 that the round machine tool table 3 has a contact surface 3 afor contacting a workpiece to be machined. The bolt 5 extends through the T-shaped groove 4 to the side of the machine tool table 3 facing the contact surface 3 a. Thus, the clamping device 2 is arranged on the side of the machine tool table 3 facing away from the contact surface 3 a, wherein only the bolt 5 extends through the T-shaped groove 4 to the side of the machine tool table 3 facing the contact surface 3 a. This has the advantage that the bolt 5 can be screwed with external thread into the workpiece to be machined.The workpiece to be machined has corresponding bores with internal threads which are designed to correspond to the bolt. By virtue of the configuration of the clamping device 2 in this way, the workpiece to be machined can be screwed directly onto the machine tool table 3, with the result that the workpiece to be machined bears against the bearing surface 3 a. This results in no loss, or at least only little loss, of space provided for machining the workpiece. Since such space is limited in a machine tool, for example, it can be optimally utilized by the clamping system 1 and the clamping device 2 according to the invention.FIG. 3 shows a clamping device 2 according to the invention in a perspective view, which can be used in a clamping system according to FIGS. 1 and 2. FIG. 4 shows the clamping device 2 according to FIG. 3 in a rotated perspective view.It is clear from FIGS. 3 and 4 that the clamping device 2 has a cover part 6 aand a lower part 6 b. The input side 2 aand the output side 2 bare coupled to one another via a transmission 7. The transmission 7 is designed as a continuously variable transmission 7. In the case of the belt transmission 7, a traction means, namely a chain 8, is used for the movement or force transmission between transmission links which are at a great distance from one another, which traction means wraps around these transmission links.FIG. 5 shows a tensioning device 2 according to FIGS. 3 and 4, wherein the chain 8 and the cover part 6 aare not shown in FIG. 5 for improved clarity. It can be seen that a gearwheel 9 with sprockets is arranged on the input side 2 aand on the output side 2 b, wherein the chain 8 converts the introduced force or the introduced torque into a longitudinal movement of the chain 8 and subsequently into a rotational movement of the output side 2 b.It is clear from FIG. 5 that the clamping device has a slotted link 10. The link 10 allows the chain 8 to be tensioned and released on the gearwheels 9 of the drive side 2 aand the driven side 2 b. The link 10 has a frame 11, wherein an upper connecting piece 12 aand a lower connecting piece 12 bare arranged on the frame 11, and wherein the upper connecting piece 12 aand the lower connecting piece 12 bare connected to the gearwheel 9 of the drive side 2 a. The upper connecting piece 12 aand the lower connecting piece 12 bare connected to the frame 11 by screws 13 a.The frame 11 can be fixed or released by means of screws 13 bto a central block 14 of the clamping device 2, so that the frame 11 is mounted displaceably on or on the central block 14. If the screws 13 bdo not hold the frame 11 fixed to the central block 14, the frame 11 and thus also the gearwheel 9 of the drive side 2 aconnected via the upper connecting piece 12 aand lower connecting piece 12 bcan be displaced in the direction of longitudinal extent L of the clamping device 2. Thus, the distance between the gears 9 of the input side 2 aand the output side 2 bcan be shortened or extended. With a smaller distance between the gears 9 of the input side 2a and the output side 2b, the chain 8 can be inserted in a simple manner. If the spacing of the gearwheels 9 is subsequently increased again via the link 10, the chain 8 is mounted on the gearwheels 9 of the drive side 2 aand the driven side 2 bin the tensioned state. By means of the displaceable link 10, the chain 8 can also be released again from the gearwheels 9 of the drive side 2 aand the driven side 2 b.However, it is also conceivable that the connection options can also be released by the screws 13 a, 13 bwith other connection techniques.It is clear in particular from the overview of FIGS. 3 to 5 that an introduced torque as a movement variable on the drive side 2 acan be converted into a rotational movement of the output side 2 bby a simple manner. As a result of the rotation of the bolt 5 resulting therefrom, the bolt can be screwed to a corresponding workpiece to be machined, wherein the workpiece to be machined has the corresponding bores with an internal thread. In this way, the workpiece and the clamping device 2 are mutually fixed on the machine tool table 3, wherein the workpiece to be machined rests on the contact surface 3 aand the clamping device 2 is held fixed in the groove.The drive side 2 aand the driven side 2 bare located on a common plane, wherein the plane is spanned in the longitudinal extension direction L of the clamping device 2. In this way, the clamping device 2 is made more compact. Due to the position of the drive side 2 aand the driven side 2 bon a common plane, the clamping device 2 is very flat.It is also clear that the cover part 6 ais screwed to the clamping device 2 by means of screws 13 c. The cover part 6 ais screwed to the central block 14, for example. The central block 14 and the lower part 6 bmay be formed in particular in one piece. However, it is also conceivable for the central block 14 and the lower part 6 bto consist of separate parts and to be subsequently connected to one another. However, it is also conceivable that the connection possibility can also be released by the screws 13 cusing other connection techniques. FIG. 6 shows the output side 2 bwith bolts 5 of a clamping device 2 according to FIGS. 3 to 5 in a schematic side view. It becomes clear that the gearwheel 9 of the output side 2 bis mounted in the clamping device 2 by means of a plain bearing. The sliding bearing makes it possible to keep the resistance caused by the sliding friction low, as a result of which good rotation of the bolt 5 can be ensured. It is conceivable that the slide bearing is designed, for example, as a slide bearing with solid friction, wherein other slide bearing types, such as, for example, with liquid friction, are also conceivable.FIG. 7 shows a schematic representation of a clamping system 1 according to the invention in a side view with a workpiece 15 to be machined. It becomes clear that a bore 16 is arranged in the workpiece 15 to be machined, wherein the bore 16 is formed with an internal thread corresponding to the bolt 5 with external thread of the clamping device 2. By introducing a movement variable on the drive side 2 aof the clamping device 2 b, the movement variable is converted into a rotational movement of the bolt 5, wherein the bolt 5 can be screwed to the workpiece 15 to be machined. In this way, the workpiece 15 to be machined can bear directly against the contact surface 3 aof the machine tool table 3.Thus, no additional installation space is taken up between the workpiece 15 to be machined and the machine tool table 3 by the clamping device 2.The clamping device 2 is held fixed to the machine tool table 3 by screwing to the workpiece 15 to be machined. The clamping device 2 is thus fixed in the groove 4 solely by the screw connection. This has the advantage that the clamping device 2 is freely movable in the groove 4 before assembly with the workpiece 15 to be machined and can be pushed to the desired position in the groove 4. Subsequently, the clamping device 2 can then be fixed to the machine tool table 3 by screwing to the workpiece 15 to be machined.List of reference characters1 Clamping system 2 Clamping device 2 aDrive side 2 bDrive side 3 Machine tool table 3 a Anlagefläche surface 4 Groove 5 Bolt 6 aCover part 6 b Unterteil part 7 Transmission 8 Chain 9 Gearwheels 10 Link 11 Frame 12 a Oberes connecting piece 12 b Unteres connecting piece 13 aScrews 13 bScrews 13 cScrews 14 Center block 15 Workpiece 16 Bore L Direction of longitudinal extent

Claims

Clamping system (1) having a machine tool table (3) with a contact surface (3a) for the contact of a workpiece to be machined and with at least one groove (4), wherein at least one clamping device (2) with a gear mechanism (7) is arranged in the groove (4), wherein the clamping device (2) has a drive side (2a) and an output side (2b), wherein a movement variable can be introduced on the drive side (2a), wherein the movement variable can be converted into a rotational movement of the output side (2b), wherein a bolt (5) with an external thread is arranged on the output side (2b), wherein the bolt (5) with an external thread protrudes from the contact surface (3a) of the machine tool table (3), wherein the external thread can be screwed into a workpiece to be machined.The clamping system (1) according to claim 1, wherein the groove (4) is a T-shaped groove (4).Clamping system (1) according to one of the preceding claims, wherein the clamping device (2) is arranged on the side of the contact surface (3a) of the machine tool table (3) facing away from the contact surface (3a), wherein the bolt (5) protrudes through the groove (4) onto the side of the machine tool table (3) facing the contact surface (3a).Clamping system (1) according to one of the preceding claims, wherein the clamping device (2) is fixed to the machine tool table (3) by screwing to the workpiece.Clamping system (1) according to claim 4, wherein the clamping device (2) is movably mounted in the groove (4) and can be fixed to the machine tool table (3) by screwing to the workpiece.Clamping device (2) for introduction into a groove (4) of a machine tool table (3) of a clamping system according to one of the preceding claims, having a gear mechanism (7), wherein the clamping device (2) has a drive side (2a) and an output side (2b), wherein a movement variable can be introduced on the drive side (2a), wherein the movement variable can be converted into a rotational movement of the output side (2b), wherein a bolt (5) with an external thread is arranged on the output side (2b).Clamping device (2) according to claim 6, wherein the clamping device (2) has a gear mechanism (7), wherein the drive side (2a) and the driven side (2b) are arranged on the gear mechanism (7).Tensioning device (2) according to Claim 7, wherein the transmission (7) is a belt transmission.Clamping device (2) according to claim 8, wherein a gearwheel (9) with sprockets is arranged on the drive side (2a) and on the output side (2b), wherein a closed chain (8) can convert the introduced force or the introduced torque into a longitudinal movement of the closed chain (8) and can subsequently be converted into a rotational movement of the output side (2b).Tensioning device (2) according to claim 9, wherein the tensioning device (2) has a link (10) for tensioning the chain (8).Clamping device (2) according to one of Claims 6 to 10, wherein the drive side (2a) and the driven side (2b) lie on a common plane.Clamping device (2) according to one of Claims 6 to 11, wherein the bolt (5) is mounted in the clamping device (2) by means of a sliding bearing.

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