EP0258483A1 - Clamping device for work pieces - Google Patents

Abstract

With a clamping device for parts, workpieces, molds and. Like., Which is particularly suitable for a grid clamping system, it is proposed to guide the clamping element (31) on both sides laterally in slide rails of a bearing block (13) which run obliquely from the top back to the front. The bearing block sits on a base body that is attached to the base plate of the grid clamping system or another base. For the relative adjustment of the clamping element on the bearing block, a screw element is provided which is in threaded engagement with at least one of the parts and is supported on the other part.

Description

State of the art

The invention relates to a clamping device for parts, workpieces, molds and. Like. According to the genus of the main claim. Such a rotogravure clamp is known (see brochure "Are high fixture costs and set-up times your problem", blüco technik 86, p. 20) and has a basic body that can be attached to a base plate, for example using screw bolts or Allen screws, which is part of a grid clamping system is. The base body carries a bearing block which has two inclined sliding surfaces spaced axially one after the other. A clamping element sits on the bearing block, which has the same inclined sliding surfaces and therefore, depending on the relative position to the bearing block, either further forward, in the direction of the workpiece and below or further back and then higher can be fixed standing. For fastening and for generating the pressure required for clamping, for example, a tool, a screw is provided which can be screwed into the bearing block and with its screw head, which is considerably widened by a washer, then presses on the clamping element from above, so that this along the inclined planes forming inclined surfaces is pressed down and onto the workpiece. However, this forward movement of the tensioning element is only possible because the bore through which the tensioning screw extends in the tensioning element is provided with a great deal of play, at least in the direction of displacement, that is to say as an elongated hole. A displacement is then only possible within the slot boundaries, and overall it can be problematic with this known intaglio tensioner that the clamping element at least as long as it is not under pressure on the workpiece to be clamped, only held loosely and also only loosely, i.e. due to the only elongated hole fastening sits completely unguided on the bearing block.

In general, the technique of clamping workpieces, parts, shapes and the like. Like., In which field the present invention finds a preferred field of application, referred to the publications article "Economical set-up of modular devices at the workplace" by Gallien / Hammer in "tz for metalworking" 1983, Issue 5 or the article "Grid clamping system with CAD supported program control reduces machine setup times "by Schwolgin in the magazine" dima ", issue 6/86, pp. 126-134.

In addition to the well-known rotogravure clamp, there are a variety of other clamping devices that are suitable for attaching molds or workpieces to grid clamping plates and that are used in fixture construction, in metal-forming deformation, in the preparation of machining at workbench workstations and the like. Like., For example, a special "blüco" - tensioner, p. 19 of said brochure, in which a clamping element is pivotally held in the bearing block about a pivot point, which is pressed forward by a screw bolt around its pivot point in the direction of the workpiece, wherein the bolt presses on the swiveling clamping element from the outside and is only in threaded engagement with the bearing block, or a ball tensioner, in which a clamping strip is held above a base bar, which can be pressed down by screwing on nuts or further screwing in stud bolts and thereby one Exerts pressure in the area of two front spherical hemispheres.

The invention has for its object to provide a clamping device in which the clamping element is guided precisely in the bearing block and there is still the possibility of performing a simultaneous movement in two planes with the clamping element, i.e. in the direction, by the more or less strong rotation of a screw element on the part to be clamped, e.g. workpiece, and down.

Advantages of the invention

The invention solves this problem with the characterizing features of the main claim and has the advantage that, with a simple structure, precise guidance and adjustment of the tensioning element in the bearing block is possible, the latter itself being slidably mounted on a base body.

It is also particularly advantageous that no frictional effects are noticeable negatively when clamping, which can arise, for example, if the respective inclined sliding surfaces along which the clamping element slides on the bearing block hinder the relative movement to one another between the clamping element and the bearing block; Such a hindrance can also result from the screw bolt in the known intaglio tensioner, which necessarily has to press the clamping element down with its screw head and, under certain circumstances, at the same time prevents the clamping element from slipping off the bearing block.

The present invention also eliminates a problem that occurs with all such rotogravure clamps, which is that only comparatively steep inclined surfaces can be used at all, so that the relative movement can take place at all due to the relative sliding on one another and no frictional inhibition occurs.

The present invention also enables particularly flat relative displacement movements between the clamping element and the bearing block, for example only in an angle of 15 ° from the back up to the front down, so that, depending on the selected angle, the ratio between the axial infeed and the pressure exerted vertically downwards (both are done simultaneously with gravure clamps) can be freely selected.

Another advantage is that, despite precise lateral, completely tilt-free guides for the tensioning element, only a central adjusting screw needs to be actuated here.

The measures listed in the subclaims enable advantageous developments and improvements of the tensioning device specified in the main claim. The smooth operation of the tensioning element, which slides along the side rails, which is stationary in the bearing block with a predetermined inclined position, i.e. tilted or tilted, is particularly advantageous so that the desired course of the displacement of the tensioning element changes both from top to bottom and in the direction of results in the object to be clamped, with any distribution of the respective proportion of the movement components, that is to say the linear subcomponent in the direction of the object to be clamped and the vertical subcomponent from top to bottom. The side slide rails can be formed in one piece on the bearing block in any shape; they are preferably round guide tubes, which can be designed as hardened and specially surface-treated, for example, highly polished sliding pegs, which are arranged inside in semicircular recesses of the bearing block, which has a general U-shape for this purpose, and in extend the rear connecting part of the two legs of the bearing block so far that there is a precise fixation and securing of the sliding pin. In a further embodiment, the sliding pins can also be fastened in the bearing block by means of tensioning screws, preferably Allen screws, which are fitted from behind. The tensioning element itself then has correspondingly inclined, preferably one-piece recesses on the side, which are also semicircular and along which the tensioning element can then carry out its combined displacement movement via the sliding pins.

drawing

• Fig. 1 eine Draufsicht auf den Grundkörper der Spannein­richtung und
• Fig. 2 eine Ansicht von vorn auf den Grundkörper der Fig. 1, teilweise im Schnitt;
• Fig. 3 eine Draufsicht auf den am Grundkörper der Fig. 1 zu befestigenden Lagerblock und
• Fig. 4 den Lagerblock der Fig. 3 in einer Ansicht von hinten, also von der Betätigungsseite für das im Lagerblock gehaltene Spannelement aus und
• Fig. 5 den Lagerblock der Fig. 3 im Schnitt längs der Linie V-V der Fig. 3;
• Fig. 6 das im Lagerblock zwangsgeführte Spannelement in einer Seitenansicht und
• Fig. 7 das Spannelement der Fig. 6 in einer Ansicht von hinten, also in der Ebene der Fig. 6 der Zeichnung von links;
• Fig. 8 zeigt die zusammengebaute Ausführungsform der Spanneinrichtung in einer Seitenansicht, teil­weise im Schnitt und
• Fig. 9 zeigt die zusammengebaute Spanneinrichtung der Fig. 8 in einer Ansicht von hinten, teilweise im Schnitt und
• Fig.10 zeigt das Betätigungsschraubelement, durch dessen Verdrehung die Verschiebung des Spannelements im Lagerblock erfolgt.

An embodiment of the invention is shown in the drawing and is explained in more detail in the following description. Show it:

• Fig. 1 is a plan view of the base body of the clamping device and
• Fig. 2 is a front view of the base body of Figure 1, partly in section.
• Fig. 3 is a plan view of the bearing block to be attached to the base body of Fig. 1 and
• Fig. 4 shows the bearing block of Fig. 3 in a view from behind, that is from the actuating side for the clamping element held in the bearing block and
• FIG. 5 shows the bearing block of FIG. 3 in section along the line VV of FIG. 3;
• Fig. 6 shows the clamping element positively guided in the bearing block in a side view
• Fig. 7, the clamping element of FIG. 6 in a view from rear, ie in the plane of Figure 6 of the drawing from the left.
• Fig. 8 shows the assembled embodiment of the clamping device in a side view, partly in section and
• Fig. 9 shows the assembled clamping device of Fig. 8 in a view from the rear, partly in section and
• Fig. 10 shows the actuating screw element, the rotation of which causes the displacement of the clamping element in the bearing block.

Description of the embodiments

The basic idea of the present invention is to forcibly guide the clamping element in the bearing block through lateral slide rails in the desired oblique inclination, to hold it securely and with high precision even against strong reaction pressure, and at the same time to operate it without problems, i.e. to move the clamping element in the combined clamping direction enable.

In the illustration in FIG. 1, the base body of the tensioning device 10 (see FIGS. 8 and 9), which accommodates and supports the bearing block itself again in an adjustable manner, is designated by 11. The base body 11 has, for example, fastening options on the base plate of a grid clamping system, namely stepped screw holes 12, which, for example, in the present case, have an essentially rectangular block shape of the base body pers can be designed as four screw holes in a corresponding distribution. These screw holes, in which Allen screws of the appropriate caliber are preferably used and can be sunk up to the shoulder 12a, so that they do not interfere with the later completion of the tensioning device and the adjustment of the tensioning element, are known fastening of the base body on a suitable grid clamping plate or another document.

A bearing block 13 (see FIGS. 3-5) sits on the upper side of the base body 11 and is connected to the base body 11 via two outer screw bolts. The bearing block 13 is seated on outer, raised longitudinal regions 14a, 14b of the base body 11, which enclose a slightly lowered surface 15 between them. The raised areas 14a, 14b have an upward toothing 16, which can be, for example, a prismatic 90 ° toothing with the pitch 1/16 ". This upward-facing double-sided toothing 16 on the longitudinal support areas 14a, 14b corresponds to a downward one directed toothing 17 on the bearing block 13 (see FIG. 5), so that here there is a first rough adjustment for the position of the bearing block 13 on the base body 11 by the bearing block in its desired position, which is then due to the interlocking toothing 16/17 is immovably fixed, placed on the base body and then the final attachment is carried out on both sides by a screw bolt which is guided through corresponding screw openings 18a, 18b in the bearing block and elongated holes 19a, 19b on both sides in the base Then two slot nuts 20 (see FIG. 9) are provided, which, as nuts extended in the direction of the elongated holes 19a, 19b (to prevent a rotary movement), serve to fasten the bearing block 13 from below (not shown) secure in the elongated holes 19a, 19b of the base body 11. The sliding blocks 20 lie against lower shoulders 21 in the elongated holes 19a, 19b.

The bearing block 13, which rests on the base body 11 and, as explained, is connected to it, has a general U-shape, as shown in FIG. 3, and consists of two legs 13a and 13b which are connected to one another via a base web 13c. The two stepped bores 18a, 18b for receiving the fastening bolts are arranged on both sides in the legs 13a, 13b, approximately centrally; furthermore, as can best be seen in FIG. 5, the bearing block has recesses 22a, 22b on both sides on the inner leg surfaces, which are inclined downwards towards the horizontal plane from the rear to the front (forwards means in the direction of the object to be clamped) run, i.e. have an inclined position with a predetermined angle. In the embodiment shown in the drawings, these recesses 22a, 22b serve to accommodate sliding pins to be inserted into them; but it is also possible that instead of the recesses, but with their course and inclination, the bearing block itself has inwardly projecting guide rails of an initially general nature (the sliding pins to be inserted into the recesses 22a, 22b are also guide rails in this sense), along which the to be explained further below Clamping element slides and is slidably guided.

The recesses 22a, 22b continue as bores in the region of the back web, which is why, to simplify their manufacture, they are semicircular in cross section on the inside of the legs. These semicircular recesses 22a, 22b serve to accommodate the sliding pins forming the guide rails or round guide tubes, which are not shown in the drawing for better understanding, and which then lie on both sides with a complementary cross section in the semicircular recesses 22a, 22b and in the continuing bores 22aʹ, 22bʹ in the connecting web 13c are also inserted to a predetermined depth. This can best be seen from the illustration in FIG. 5, which, although in cross section represents a central threaded bore, shows in dashed lines the bore 22aʹ lying behind in this view. This bore extends up to a distance A from the inside of the connecting web in this; This is followed by an inwardly projecting ring projection 23, whereupon the bore then expands again at 24, for example to the same diameter. The reason for this is that the sliding pegs inserted up to the height A in the bores 22aʹ on both sides of the legs strike the ring projection 23 and from the other side, that is to say from the bore 24, a screw connection, preferably an Allen screw, is inserted into a facing central threaded hole is screwed into each slide pin and the slide pin is thus securely fixed and immovable first in the semicircular recesses 22a, 22b of the legs 13a, 13b on both sides and of course in the full bore stanchions in the connecting web 13c secures and clamps.

The construction of the bearing block 13 is then completed by a central bore 25 in the connecting web 13c, which has an internal thread and serves to accommodate the adjusting screw for the displacement of the tensioning element; this set screw is shown in Fig. 10 and designated 26 - this will be discussed further below.

For reasons that lie in the oblique displacement movement of the tensioning element, which will be discussed further below, the rear surface 27 of the connecting web 13c is designed inclined in such a way that this surface is perpendicular to the threaded bore 25 and also to the bores 22aʹ, 22bʹ runs. Furthermore, the upper surface 28 of the connecting web is inclined obliquely downward and thus adapts to the inclined inclination of a counter surface 29 of a rear projection 30 on the tensioning element 31, which is shown in FIG. 6.

Finally, it should also be pointed out that on both sides the two legs 13a, 13b have an approximately rectangular or square cutout 29 at the front, that is to say in the direction of the object to be clamped, the stepped design when the clamping element is essentially fully retracted, as shown in FIG. 8 corresponds to the front surface of the tensioning element, so that it can easily get close to the object to be clamped.

The tensioning element itself is designed as shown in the side view of FIG. 6; it fits snugly in the space formed by the two legs 13a, 13b of the U-shape of the bearing block and has laterally the semicircular outwardly projecting sliding pin on the inner surfaces of the bearing block on corresponding lateral recesses 32a, 32b, so that the received between the two legs of the bearing block Clamping element along its bilateral guide rail arrangements can simultaneously be moved forwards and backwards and, following the freely adjustable, preferably 15 ° inclination of the sliding pins, can be moved from top to bottom.

The clamping element 31 is block-shaped with front, stepped front surfaces 33 and 34, which rest against the object to be clamped or the workpiece - both front clamping surfaces 33, 34 are preferably toothed so that they cannot slip off.

A rear abutment surface 35 comes to bear against the inner inclined surface 35ʹ of the connecting web 13c of the bearing block 13 when the tensioning element 31 is fully retracted; in this position, the projection 30, which is pulled out backwards, on the tensioning element 31 also lies fully above the upper inclined surface 28 of the connecting web 13c. This projection covers the inner area of the U-shape of the bearing block even in the extended position of the clamping element and prevents the penetration of chips, for example, during machining and. the like

The fine displacement of the clamping element 31 is then carried out by the thread engagement of the already mentioned above 10 screw element 26 of FIG. 10 both in the threaded bore 25 in the bearing block and in a correspondingly aligned central threaded bore 36 in the clamping element 31. The two external threads 26a, 26b in the screw element 26 are opposite, that is, once a left-hand thread, once a right-hand thread with the corresponding opposite thread formations in the bores 25 and 36, so that despite the formation of these threads as fine threads with a small pitch, a sensitive as well as rapid displacement of the tensioning element along its guide slide pin on both sides is possible when the screw element 26 is rotated. This rotation takes place on the bearing block 13 from the rear, where in the assembled representation of FIG. 9 the screw element, which is preferably provided here with a hexagon socket recess 37, can be seen.

It is to be understood that the present invention is susceptible of numerous modifications; for example, the lateral guide rails can also be designed as lateral oblique projections on the tensioning element, which then engage in corresponding guide recesses in the inner sides of the U-legs 13a, 13b of the bearing block 13.

It is also possible to provide the screw element 26 with only a thread and then to store it stationary in one of the parts performing the relative movement to one another, i.e. the bearing block or the clamping element, for example by engagement of an inner bore ring shoulder in a ring recess on the screw element, so that at a twist then only one win de with its thread engagement in the other part causes the relative displacement movement.

All features shown in the description, the following claims and the drawing can be essential to the invention both individually and in any combination with one another.

Claims (11)

1. Clamping device for parts, workpieces, molds and. Like., In particular rotogravure clamps for grid clamping systems, in fixture construction, for cutting deformation u. Like., With a base body which is fastened to a base, a bearing block which can be fastened to the base body in different positions and a clamping element which is slidable in the bearing block and acts on the part to be clamped, characterized in that the clamping element (31) on both sides laterally at an angle from above is guided in the rear downward forward sliding rails, which are stationary in the bearing block (13) or on the clamping element (31), and that a screw element (26) is provided for adjusting the clamping element (31) and with at least one of the parts, i.e. bearing block ( 13) and / or clamping element (31) is in thread engagement. 2. Clamping device according to claim 1, characterized in that the bearing block (13) is U-shaped and the slide rails in the inner side half-round recesses (22a, 22b) in the two Legs (13a, 13b) arranged sliding pegs are formed. 3. Clamping device according to claim 1 or 2, characterized in that the bearing block (13) is mounted on a base body (11) which in turn is fastened to a grid clamping plate, a base or the like by fastening means. 4. Clamping device according to one of claims 1 to 3, characterized in that the base body has lateral elongated holes (19a, 19b) through which clamping screws, which extend in the direction of the elongated holes in the base body and which are displaceable relative to these, engage in the elongated holes through lower sliding blocks (20) are kept. 5. Clamping device according to claim 4, characterized in that the superimposed surfaces of the lower base body (11) and on this mounted bearing block (13) interlocking teeth (16, 17) for mutual relative fixing. 6. Clamping device according to one of claims 1-5, characterized in that the bearing block (13) of two lateral legs (13a, 13b) and a rear connecting leg connecting the two legs (13c) is formed and that the sliding pin Continue receiving semicircular recesses (22a, 22b) in the inner leg surfaces in the connecting web (13c) as full bores (22aʹ, 22bʹ). 7. Clamping device according to claim 6, characterized in that the semicircular recesses (22a, 22b) and in the connecting web (13c) continuing full bores (22aʹ, 22bʹ) are arranged so as to run obliquely from the rear to the front with a predetermined angle (15 °). 8. Clamping device according to one of claims 1-7, characterized in that the half-round recesses (22a, 22b) in the side legs (13a, 13b) in the bearing block (13) continuing full bores (22a, 22b) in the connecting web (13c) an inwardly projecting ring projection (23) is interrupted, on which, starting from the legs, the sliding pins forming the guide rails for the adjustment of the tensioning element and, starting from the outer surface of the connecting web (13c), there are fastening screws which are screwed into the sliding pins for fixing them. 9. Clamping device according to one of claims 1-8, characterized in that the clamping element is received flush in the space formed by the two legs (13a, 13b) of the bearing block (13) and with lateral, the oblique position of the sliding pin or guide rails following the semicircular recesses Receives sliding pin or guide rails and slides along them. 10. Clamping device according to one of claims 1-9, characterized in that the screw element adjusting the clamping element (26) on both sides up to has a central separating recess, threads which run in opposite directions and which engage in correspondingly opposite threads of a central threaded bore (25) in the connecting web (13c) or a threaded bore (36) in the tensioning element (31) in such a way that when the screwing element is rotated, the screwing element simultaneously emerges from the Turning the bearing block out or into it and vice versa into the clamping element. turns out of this, such that the relative adjustment speed between the bearing block and the clamping element per revolution of the screw element is twice as large. 11. Clamping device according to one of claims 1-10, characterized in that the clamping element (31) has a rear, in the extended state the leg space and the guide parts covering projection (30).

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