DE2900109A1 - Clamp for mitre joint of picture frame - has two metal blocks secured by nails and forced together by bolt - Google Patents

Abstract

A clamp for holding the mitred joint of a picture frame consists of two metal blocks (10, 12). A block (10, 12) is secured by a screw-nail (36) to each of the joint members (40, 42). A bolt (14) with a hexagonal head is pushed through the clearance hole in the block (10) and retained by a spring ring (20). The threaded end of the bolt (14) is screwed into the tapped hole in the block (12) and pulls the two blocks (10, 12) together and in so doing clamps the frame members (40, 42). A guide bar fixed to one of the blocks (10) and sliding in a groove in the other block (12) ensures the correct alignment of the joint.

Description

Description:

Clamping device for the mutual clamping of workpieces The invention relates to a clamping device for the mutual clamping of opposing surfaces of workpieces that are to be firmly connected to one another in parallel or at an angle with the features of the preamble of claim 1.

A clamping device of this type is already known. It enables it, opposing surfaces to be connected to each other parallel or under one Press the workpieces to be assigned to one another. Their tendons are for this purpose each equipped with a cylindrical pin as a holding member, each are to be fixed on one of the workpieces to be clamped together.

For this purpose, a hole must be drilled into each workpiece, into which the tenons of the tendons serving as holding members are to be inserted. Then the actuator is to be rotated so that the pins approached each other and thereby the mating surfaces are pressed against one another.

In this known tensioning device, the tendons are each held pivotably at the ends of a support strip and between the tendons and the actuator is arranged parallel to the support strip. This is For example, formed by a hexagonal profile, threaded holes in the front ends are arranged, the threads of which have opposite pitch.

Threaded pins are hinged to the tendons which are in the threaded bores are led. By rotating the actuator are thus to generate a Clamping pressure to press the opposing surfaces of two workpieces together, the tendons pivoted relative to one another so that their pins move towards one another.

This jig has the disadvantage that the arrangement of the the pin receiving holes on the workpieces largely on the mutual Center distance of the tenons of the tendons matched in their parallel alignment must become.

Furthermore, the pivotable arrangement of the tendons leads the support bar to the fact that the workpieces inevitably tilted when clamping which means that if there is too much tension between the opposing surfaces, a Gap arises.

In addition, the constant spacing of the tendons on the Carrier strip to keep a variety of clamping devices ready for workpieces to be able to brace mutually different widths In the end it is a technically complex one and accordingly in the production expensive construction.

The invention is therefore based on the object, one in the preamble of claim 1 explained clamping device in such a way that the disadvantages the known clamping device are avoided and which is suitable for a variety the clamping devices that are usually to be kept ready of the initially explained Type to replace.

This task is achieved by the characterizing features of the claim 1 solved.

The clamping device according to the invention thus enables one of the both tendons by turning the adjusting spindle in its axial direction steplessly to be adjusted so that the mutual distance to be determined on the workpieces Holding shafts can be changed accordingly. This results in the main advantage that now workpieces to be clamped together to fix the holding shafts, for example Suitable places can be drilled and then through Turning the adjusting spindle corresponding to the spacing of these workpiece bores Adjust the spacing of the retaining links.

The arrangement of the tendons on the adjusting spindle also achieved that the workpieces can no longer tilt during clamping. So that's a Gap formation between the mating surfaces avoided.

The operation of the clamping device is very easy, whereby this only consists of two tendons and the adjusting spindle, so that compared to 'known clamping device, they can be manufactured considerably more cheaply is.

Here, both tendons can be adjusted relative to one another according to claim 2 with one clamping member an internal thread running on the adjusting spindle be connected. Furthermore, according to claim 3, the adjusting spindle can support the Form tendons, it is advantageous to design the construction according to claim 4 In a preferred embodiment, the tendons are analogous to the known ones Clamping device held on the support shaft in a non-rotatable manner relative to one another, see above that it is not necessary to axially adjust one tendon of this to be held by hand.

An advantageous development of such a clamping device is Subject matter of claim 5. In such a jig there is thus the Possibility of using the tensioning member, which can be adjusted in the axial direction to the adjusting spindle to fix another tendon in at least two different positions, whereby in the case of two contact surfaces, these are advantageous to each other at an angular distance of Will assign 90 °. Accordingly, the holding shafts of the tendons, for example both at a parallel and at an angle of 900 to each other Provide position on the adjusting spindle and in this position relative to each other Adjust in the axial direction of the adjusting spindle.

In a preferred embodiment, the holding shafts are according to FIG Claim 6 designed as holding mandrels, from which the essential advantage results that now for the fixing of the holding shafts on the workpieces ìnvlatterere none More bores must be made and the retaining pins can by Driving into workpieces made of wood or hard fiber material, for example, quickly and be reliably fastened, the retaining mandrels are given such a diameter that they do not have any annoying or particularly eye-catching openings on the Workpieces left behind.

For this purpose, the holding thorns according to claim 7 by nails, in particular screw nails provided with a key head, be formed, wherein Screw nails have the advantage that they can be turned by turning their key head can easily be removed from the workpiece in question.

In a further advantageous embodiment, it is provided according to claim 8, to arrange at least one of the two holding mandrels in the tendon in such a way that whose tapered end piece, when it is driven into a workpiece, the approaching the other retaining mandrel. Such a mutual assignment of the holding mandrels leads to the fact that already when driving the same into the workpieces a force component becomes effective, under the action of which the opposing surfaces are moved towards one another and, if necessary are already applied to each other.

A design variant that can be used with particular advantage is the subject of claims 9 undlo. This embodiment enables in particular a parallel clamping of workpieces, the surfaces of which are larger Have width by placing the tendons on opposite sides of the lierkstückseiten are connected to each other and thereby given a stiffened construction is.

Such a clamping device according to FIG Claim n to train so that on both sides of the workpieces on the tendons Clamping forces can be generated.

A particularly favorable construction is the subject of the claim 32. It makes it possible to set the holding shafts on the workpieces without their To injure the surface by the holding shafts designed as threaded spindles serve to clamp the workpieces on a workpiece contact surface of the tendons. In this way, the opposing surfaces of the workpieces are in a mutual parallel position can be used when clamping together, it is a prerequisite that the workpieces, when the holding shafts are placed against them, they can still be pivoted about the shaft axis are, which is why it is beneficial to have a pressure member on the holding shafts, in particular a rotatable pressure plate to be provided.

Finally, in a further embodiment of such a device according to claim 13 in a central passage of the threaded spindles forming the belt shafts axially adjustable a centering member, in particular one with a sharpened end piece be arranged in a workpiece drivable retaining mandrel. This makes it possible Before the threaded spindles are tightened, the workpieces are closed relative to the spindle axis center and align their mating surfaces in a parallel position accordingly to be able to pivot before they are in the tendons by tightening the threaded spindle finally determined and braced to each other.

In the subsequent description of shown in the drawing Embodiments of the clamping device according to the invention and / or in the claims further features and details of the invention are explained. In the drawing FIG. 1 shows a front view of a first exemplary embodiment of a tensioning device Connection with two workpieces clamped together by them; Figure 2 is a plan view on the clamping device according to Figure 1; Figure 3 is a section through the clamping device along line 3-3 of Figure 1; Figure 4 is a plan view of the clamping device, in the condition attached to the workpieces to be mutually clamped, the Workpieces themselves are not yet aligned, Figure 5 shows a possible application example inventive devices according to Figure 1 to 3; Figure 6 is a diagrammatic Representation of a box body, its body parts by means of clamping devices are clamped together according to Figure 1 to 3; Figure 7 is a front view of a second embodiment of the clamping device, Figure 8 is a plan view the clamping device according to Figure 7, wherein the threaded spindles are cut; FIG. 9 shows a section along the line 9-9 in FIG. 7 through the clamping device, wherein in the shown clamping member of the clamping device a workpiece before clamping is centered; FIG. 10 shows a representation similar to FIG. 9, the workpiece in this tendon is clamped.

The first embodiment shown in Figures 1 to 3 The clamping device according to the invention has two designated as a whole by 10 and 12 Tendons, which are formed, for example, by cuboid metal bodies. 14 with a carrier shaft is referred to, which penetrates both tendons transversely, namely, it extends essentially parallel to a flat workpiece contact surface 16 or 18, which is provided according to Figure 1 on the underside of the tendons.

The support shaft is with a cylindrical shaft section, for example in tendon 10, rotatably mounted, but against), aK; all displacement by one on the support shaft placed locking ring 20 and one for actuating the Carrier wave serving key head 22 secured. Instead of A rotary handle or the like could also be provided on the shaft with the key head. With a shaft shaft 24 having an external thread, the carrier shaft is in one Threaded bore of the clamping member 12 guided axially adjustable. 26 denotes a flat contact bar, which with its one end piece on one of the tendons, for example on the tendon 10, is rigidly attached by rivets 28 on the rear side. The investment bar extends parallel to the carrier shaft in the direction of the other tendon and rests there against a rear, flat contact surface 30 with a friction fit. This A further contact surface 32 is assigned to the clamping member 12, namely this is located on the top and offset by 900. The contact surfaces 30, 32 are preferably located lower on the corresponding side surfaces of the clamping member 12 provided, and the thickness of the contact bar is chosen so that this is the distance the contact surfaces to the corresponding side surface of the tendon compensates. Likewise, the contact strip is on a correspondingly lower contact surface of the tendon 10 attached.

In each tendon there is a retaining mandrel, preferably in the form of one a key head 34 having screw nail 36 both rotatable and arranged axially adjustable, and that these screw nails extend according to Figure 3 laterally of the carrier shaft and perpendicular to its axial direction through the tendons through. The nail length is dimensioned such that it is inserted into the maximum State in the tendons a piece from their workpiece contact surface 16 respectively. 18 protrude perpendicular to this. The pointed screw nails 36 are in the Tendons, for example, with the help of a plastic plug inserted into them 38 out of friction, so that they are also partially pulled out from the tendons maintain their position and also, for example, when storing the tensioning device cannot fall out of the tendons.

Due to the contact strip 26, both tendons are mutually such stipulated that although the mutual spacing of the carrier shaft is rotated can be continuously changed, but that, due to the between the tendon 12 and the thread of the shaft shaft 24 existing friction, the clamping member 12 when twisting the carrier shaft cannot rotate. So there is inevitably an axial adjustment this tendon take place, although one does not hold the same for this purpose by hand got to.

As can be seen from FIG. 2, the screw nails 36 are located in the one defined by the contact surface 30 and the contact strip 26 position of the clamping member 12 relative to the clamping member 10, in a common, to the axis of the Carrier shaft 14 parallel plane a-a. When the carrier shaft is rotated, it shifts the screw nail 36 also in this plane. For example, for mutual bracing two wooden strips 40, 42 parallel to each other or, as Figure 2 shows, e.g. below an angle of 900, these are on mating surfaces and in the latter case on miter surfaces 44 and 46 to be braced together. For this purpose, the tendons are first or their screw nails 36 on the wooden strips 40, 42 to determine which can be achieved in a simple manner by driving the screw nails into the workpieces can be accomplished.

It does not matter at all in which reciprocal See the distance between the two tendons and where they are the screw nails e.g. on the top of the wooden strips relative to the miter surface 44 or 46 of the respective wooden strip can be positioned. It is only essential that now there is the possibility of the wooden strips around the axis of the screw nails 36 to be able to pivot relative to one another essentially in the same plane.

The screw nails should preferably be driven into the wooden strips in such a way that that the tendons finally with their workpiece contact surface 16 and 18 respectively sit on the top of the wooden strips. Then the carrier shaft 14 is to be rotated so that that the clamping member 12 moves in the direction of the clamping member 10 to the miter surfaces to bring each other to the plant. To do this, it is possible to order the workpieces the axis of the screw nail 36 driven into this also together with the To pivot the jig about the axis of the screw nail, the according to the other Workpiece is set. These swivel options allow the wooden strips to align flush with each other on the front sides of the miter surfaces, such as this can be seen from FIG. After the alignment has taken place, you can then go through corresponding further rotation of the carrier wave the miter surfaces under pressure lay against each other or

clamp the workpieces against each other.

The length of the screw nails is advantageously dimensioned so that at the parallel adjustment of the tendons when clamping the workpiece surfaces to be placed against each other no tilting of the workpieces due to the unilateral force attack can take place.

The figures show further application examples of the clamping device 5 and 6.

Figure 5 illustrates how, for example, flat workpieces 48, 50 can be braced with each other, which are perpendicular to each other.kn this The case is the clamping member 12 by correspondingly rotating the support shaft 14 initially to remove from the carrier wave and reapply to the carrier wave that the contact strip 26 rests against the contact surface 32. Accordingly, the Screw nails in mutually perpendicular directions so that the tendon 10 on a flat side of the workpiece 48 and the clamping member 12 on a flat side desWskstückes 50 can be set. Figure 5 also shows that it is possible these workpieces are tilt-stable with one another by using two clamping devices 56, 58 to connect r when the clamping member 12 of these clamping devices at opposite one another Flat sides, for example the workpiece SO is attached.

Figure 6 shows, for example, the use of clamping devices, around adjacent side walls 60, 62, 64, 66 of a rectangular furniture body or the like. To be braced together, including the tendons 10, 12 of various tensioning devices 68 to be determined in each case in the corner area of the body at a front edge are. The side parts can be on their miter surfaces to be braced together also have connecting means such as dowels or the like.

The further exemplary embodiment shown in FIGS. 7 to 10 The clamping device according to the invention is shown in FIG. 9 with U-shaped tendons 70, 72, with a carrier shaft designated 74 according to FIG. 7, for example in the lower U-leg 78 in. to the embodiment according to Figurel analogous arrangement is provided. The upper U-legs 76 are of a cylindrical guide shaft 80 penetrated, which is arranged axially parallel to the carrier shaft and its length the maximum adjustment range of the two tendons 70, 72 determined by the when the maximum distance between the tendon 72 and the tensioning guide shaft is reached 8o member 70 attach circlips 82 of the type to the outside of the same. the The inner surface of the lower U-legs 78 according to FIG. 7 forms a workpiece contact surface 86. In the opposite U-leg 76 of the tendons is perpendicular to the guide shaft 80 and perpendicular to the contact surface 86 a rotatable by means of a knurled pot 88 Threaded spindle 90 guided, the end of which can be pressed onto the workpiece by a pressure plate 92 carries the rotatably arranged on the threaded spindle and applied to a workpiece is.

The threaded spindles are penetrated by a central passage 94, in which rotatable and axially adjustable with a molded one End piece 96 of relatively small diameter equipped Ilaltedorn 98 arranged is. This protrudes with a shaft part from the free face of the knurled head 88 out and is there for manual operation. Also with a knurled head 100 equipped.

With 102 is the connecting web connecting the U-legs 76, 78 to one another denotes whose flat side located within the U-shaped tendon is indicated at 104.

This flat side and preferably also the outer flat side 106 is arranged at an angle of, for example, 450 to the longitudinal direction of the U-legs, so that both inner flat sides 104 of the tendons 70, 72 together form an angle 900 define.

As Figure 8 shows, the threaded spindles 90 are in a plane, in which the carrier shaft 74 is also located, while the guide shaft 80 for this purpose is arranged in a parallel plane and according to Figure 9 in the U-legs 76 is located behind the threaded spindles 90.

In this embodiment, the guide shaft 80 takes on leadership and support function, so that both tendons on both sides of the workpieces to be clamped are stabilized.

This clamping device is particularly suitable for clamping workpieces, which can be assigned to one another at an angle, in particular of 900, like the one in Figure 8 is indicated by dash-dotted lines.

The clamping device is particularly suitable for Wooden profiles, which, for example, have a strong profile on one side transversely to the longitudinal direction are to be able to clamp advantageously. This is done first in the individual tendons to apply the pressure plate 92, for example, to a flat workpiece surface in order to, for example align a profile strip on the contact surface 86 with its profiled surface.

Then the sharpened end piece 96 of the holding mandrel 98 to center the profile strip on the contact surface, pressed into the profile strip. For this purpose, the retaining mandrel can also have an external thread in a corresponding internal thread of the threaded shaft 90 be axially adjustable to this centering as possible to be able to do it sensitively and thereby prevent the material from tearing. After centering, the threaded spindle must be loosened in such a way that the pressure plate rests only lightly on the profile strip. Then the workpieces are around the axis of the holding mandrel 28 to pivot accordingly to the opposing surfaces to each other align.

The tendons can then be adjusted by turning the carrier shaft adjust relative to one another in order to thereby place the opposing surfaces against one another. To put pressure on the opposing surfaces are finally, before the final Brace, retighten the threaded spindles.

In place of the leadership 80 can just as well be another Carrier wave occur, which is advantageous to the carrier wave 74 in an interchanged arrangement will provide in the U-legs 76.

Let between contact surface 86 and pressure plate 92 of the tendons Workpieces in a parallel position are particularly advantageous each other bracing, especially fine wooden parts, such as those used in model making Find uses that cannot be mutually clamped with screw clamps.

For this purpose, the clamping device can, for example, by means of one indicated by dash-dotted lines in Figure 8 and e.g.

on the connecting web 102 of the clamping member 72 molded extension piece 108 e.g. in a vice, or by means of means arranged in the U-legs 78 Attach screw mounting holes 110 to the table.

Claims (13)

Claims: Clamping device for the mutual clamping of Opposing surfaces to be firmly connected to each other by parallel or at an angular position Workpieces, with two arranged on at least one common elongated carrier, in particular by means of a contact surface on each of the tensioning elements that can be applied to a workpiece, each one to be fixed on a workpiece and extending transversely away from the carrier Have holding shaft and to generate the clamping pressure by means of a rotatable Threaded members are adjustable and lockable relative to one another on the carrier, d a d u r c h g e k e n n n z e i c h n e t that the threaded member is an adjusting spindle (14) for parallel displacement of at least one tension member (12) in the longitudinal direction of the carrier forms. 2. Clamping device according to claim 1, characterized in that with one clamping element (12) an internal thread running on the adjusting spindle (14) connected is. 3. Clamping device according to claim 1 or 2, characterized in that that the adjusting spindle (14) forms the carrier of the tendons (10, 12). 4. Clamping device according to claim 3, characterized in that the adjusting spindle (14) on the one hand rotatable in a clamping member (lo), but axially immovably stored and on the other hand with an external thread having spindle section (24) in a threaded bore of the other tendon (12) is performed. 5. Clamping device according to one of the preceding claims, whose Tendons are held non-rotatable relative to each other, characterized in that, that a strip-like contact piece (26) is attached to a tendon (lo), the one on the other tendon (12) at least two angularly spaced from one another Contact surfaces (30,32) are assigned. 6. Clamping device according to one of the preceding claims, d a d u r c h g e k e nnn z e i c h n e t that the holding shafts form holding pins which are in the tendons (10,12) from a standby position in which their mandrel end piece which can be driven into the workpiece (40 or 42) essentially within of the tendon is located, for driving into a workpiece in particular frictionally are axially adjustable. 7. Clamping device according to claim 6, characterized in that the Holding pins by nails, in particular screw nails provided with a key head (34) (36), are formed. 8. Clamping device according to claim 6 or 7, characterized in that that at least in one tendon of the retaining mandrel in the plane of both retaining mandrels is arranged obliquely such that its tapered end piece when driving in a workpiece approaches the other holding mandrel. 9. Clamping device according to one of the preceding claims, characterized characterized in that the tendons are spaced parallel to the adjusting spindle (14) have shaft-like guide member and that adjusting spindle (14) and guide member essentially in a common plane and the holding shafts arranged in addition to workpiece contact surfaces in an area between these parts are. lo. Clamping device according to claim 9, characterized in that the tensioning elements (70, 72) are U-shaped, with the adjusting spindle in one U-leg (78) (74) and the guide member is arranged in the other U-leg (76). 11. Clamping device according to claim 9 or, characterized in, that the guide member provided in the clamping members (70, 72) is either a cylindrical one Shaft (80) or a shaft, the latter, analogous to the adjusting spindle (74), but to this in an interchanged arrangement in the tendons (70, 72), in one Tendon rotatable, but axially unadjustable and in the other tendon with one a shaft section having an external thread is guided in a threaded bore. 12. Clamping device according to claim 9 oderlo, characterized in that that the mutually adjacent U-legs (76) of the tendons (70, 72) are perpendicular holding shafts arranged for adjusting spindle (74) and shaft (80) by means of threaded spindles (90) are formed on their facing the workpiece (10 'or 110) to be clamped At the end of a pressure member, in particular a rotatable pressure plate (92), carry. 13. Clamping device according to claim 12, characterized in that axially adjustable in a central passage (94) of the threaded spindle (90) Centering member, in particular one with a sharpened end piece (96) in a workpiece (108 or 110) retractable retaining mandrel (98) is arranged.