Camera track with support device

Abstract

Camera track (200) with a length-variable support device (100), with a clamping force-based locking device (4, Z4, 7, 10) for fixing to a predetermined length, characterized in that the clamping force increases with increasing support load and a movement of the movable brake shoes (10) of the locking device, which directly exert the clamping force and are arranged on both sides of the longitudinal axis (X) of the support device, in the direction of the clamping force is accompanied by a change in distance between two axes of rotation (Z4, Z10) perpendicular to the longitudinal axis (X), one of which a axis of rotation (Z4) is fixedly connected to the area of ​​the support device that receives the support load.

Description

[0001] The invention relates to a camera track with a length-adjustable support device with a locking device based on clamping force for fixing to a predetermined length, which can be used to support and level the camera track.

[0002] Such support devices are well known in the art, for example, in the form of telescopic tubes, in which the relative mobility of two mutually movable tubes is inhibited by a locking device such as a toggle lever brake, thus allowing the length of the telescopic tube to be fixed. Furthermore, supports with a fixed length are known for supporting camera tracks, which have a correspondingly simpler structure.

[0003] DE 1 073 753 A discloses a tripod incorporating gravity to release a friction lock for rapid pivoting through 180° by means of joints or cams, thereby providing asymmetric support.

[0004] DE 84 360 13 U1 discloses a height-adjustable table in which a spring mechanism pushes knee levers into the braking position and the weight force is absorbed by a lift cartridge.

[0005] DE 10 2010 033 533 A1 relates to a support fitting for the height-adjustable support of a substantially horizontally extending support rail and / or guide rail for moving camera carriages or camera cranes.

[0006] The invention is based on the object of providing a camera track with a length-adjustable support device which is improved with regard to the reliability and effectiveness of its support even under higher loads.

[0007] This object is achieved by the invention by providing a camera track with the features of claim 1. It is characterized, among other things, in that the clamping force increases with increasing support load.

[0008] Unlike the telescopic tubes described above from the prior art, the locking device no longer applies a one-time, fixed clamping force, which, once the friction-based holding force it imparts is overcome by the support load, no longer guarantees the specified length of the support device (or, in the case of vertical installation, the height of the support). Rather, according to the invention, the clamping force increases with increasing support load, thus the locking device acts self-locking, and the preset length (height) is reliably maintained. In particular, the support device is designed to support support loads of at least 800 kg, in particular at least 1000 kg.

[0009] Particularly preferably, the length (height in upright use) of the support device is continuously adjustable so that, for example, the leveling of a camera path with very high accuracy is possible without additional measures.

[0010] The clamping force acts transversely to the applied support load. As a normal force, it creates a holding force based on frictional engagement that opposes the support load. A gear unit is useful for converting the support load F ST into the clamping force F KL in a ratio of F ST / F KL ≤ 1 is provided. This gearing could, for example, and preferably, be formed by a lever arrangement. In particular, it is provided that the lever arrangement has a first axis of rotation that is firmly connected to the region of the support device that receives the support load.

[0011] Particularly preferably, a pretensioning device is provided for pretensioning the locking device in the sense of a clamping action. This can preferably comprise an elastic part for applying the actual pretensioning force, as well as a force transmission mechanism. The latter can also comprise a lever arrangement and, in particular, also access the first rotation axis described above.

[0012] The force transmission mechanism of the pretensioning device preferably also has a second axis of rotation. In this case, it is particularly provided that a movement of the movable parts of the locking device that directly exert the clamping force in the direction of the clamping force is accompanied by a change, in particular an increase, in the distance between these two (the first and second) axes of rotation. According to this preferred arrangement, the support load, on the one hand, but also the force exerted by the elastic part of the pretensioning device, contributes to this increase in the axis distance.

[0013] Furthermore, a release device for releasing the locking mechanism is preferably provided. The release force to be applied can be applied manually, i.e., without the use of tools, and is essentially determined by the force required to overcome the preload force causing the locking device to be preloaded, for example, the force of an elastic spring.

[0014] Preferably, a limiting device is further provided for limiting the adjustment of the gear mechanism for converting the support load into the clamping force. This limiting device prevents, in particular, parts of the lever arrangement mounted for rotation about the first axis of rotation from being rotated beyond their extended position. Movement in the opposite direction of the gear mechanism for releasing the clamping force can also be expediently limited.

[0015] The height of the camera track can therefore be levelled particularly easily and in a short amount of time, and the set level is maintained even under high loads due to the inventive design of the support devices supporting the camera track.

[0016] The camera track can be equipped with rails which have a protective device on the running surface which is displaceable by a predetermined amount in the longitudinal direction with respect to the rail.

[0017] While protective devices for camera track rails are known in the prior art, these are firmly bolted to the rail. Within the scope of the invention, it has also been determined that, particularly after repeated high loads, the set rail path cannot be permanently maintained. In particular, it may even be necessary to completely loosen and then retighten these prior art fastening screws. The further aspect of the invention, namely making the protective device movable by a predetermined amount in the longitudinal direction relative to the rail, is based on the realization that this movable capability can prevent the protective device and rail from deforming, at least partially and irreversibly, under load.

[0018] In a further development of this aspect, it is preferred that the protective device has a greater surface hardness than the rail. For example, the rail could be made of aluminum, in particular in the form of an extruded aluminum profile, while the protective device could be made of steel, for example.

[0019] In principle, however, other materials are also conceivable, whereby the protective device should preferably be elastic, in particular to the extent that it allows the protective device to be clipped onto the rail.

[0020] From a design perspective, it is further preferred that two longitudinally successive rails are connected to each other via a coupling device, which is longitudinally displaceable relative to the two rails by a predetermined amount, and wherein the protective device is fixed to the coupling device. The coupling device can have a centering mechanism, in particular by a two-part design with a male and a female part, whose particularly conical interlocking effects the centering.

[0021] The guard thus forms the actual running surface of the rail and absorbs damage that would otherwise be sustained by the base rail itself. It can be replaced as soon as it no longer ensures sufficiently smooth guidance of a camera carriage.

[0022] Further features, details and advantages of the invention will become apparent from the descriptions of the accompanying figures, of which Fig. 1 shows a perspective external view of a support device, Fig. 2 an axial sectional view of the support device from Fig. 1 shows, Fig. 3 a perspective view of a pressure bolt and a locking mechanism of the Fig. 1 and Fig. 2 shows the support device, Fig. 4 shows a further axial sectional view of the support device together with the supported rail and an actuating mechanism for releasing the holding force, Fig. 5 shows a perspective view of a camera path, Fig. 6 shows an axial section of a rail of this camera track, and Fig. 7 shows a cross-section of this rail.

[0023] Fig. 1 shows an exemplary support device 100 in a perspective external view. An inner tube 2, which can be placed on the ground in the arrangement of this exemplary embodiment, is received by its upper section in an outer tube 1. The load to be supported is introduced into the outer tube 1 via the cover 3 closing the outer tube at its upper side into the support device 100. However, the upper end 15 of a bolt 5 (described below), which protrudes from an opening in the cover 3, is not subjected to the supporting load.

[0024] In the illustrated embodiment, the cross-section of the outer tube 1 is not round, but rather has two opposing flat surfaces and two curved surfaces connecting these flat surfaces. This specific shape is not essential to the invention, but rather allows interaction with the support fittings of a camera track disclosed in WO 2012 / 016714, which originates from the same applicants. However, the present invention is not further limited with regard to the shape of the outer tube 1 or the inner tube 2.

[0025] The exact structure and effect of the locking device of the support device shown is better understood from the Fig. 2 and Fig. 3. In the axial section taken along the longitudinal axis X, the Fig. 2, in turn, shows the inner tube 2, which is accommodated in the outer tube 1. A spacer 11 between the outer tube 1 and the inner tube 2 ensures smooth sliding of the inner tube 2 in the outer tube 1.

[0026] Also housed in the outer tube 1 and firmly connected thereto is a pressure bolt 4, which is hollow in its upper region. On the downward-facing side, the pressure bolt 4 has two opposing flanges 14, between which a receiving space is created for a lever arrangement of the locking device, described below. The flanges 14 also hold an axis Z4 extending transversely to the longitudinal direction X. Due to the connection of the pressure bolt 4 to the outer tube 1 and the fixed position of the axis Z4 with the pressure bolt 4, a support load F acting on the cover 3 in the absence of the locking device (or when released) STmove the pressure bolt 4 along with the axis Z4 downwards along the longitudinal axis X and thus cause a relative movement of the axis Z4 to the inner tube 2.

[0027] However, if the locking device is not released, this movement is prevented. For this purpose, the locking device has L-shaped links 7, which are mounted to rotate about the axis Z4. At the short end of the L-shaped links 7, brake shoes 10 are mounted to rotate (axis Z10), the orientation of which is parallel to the longitudinal axis X is ensured regardless of the rotational position of the L-shaped links 7 about the axis Z4 due to this rotatable connection (axis Z10). A rotation of the L-shaped link 7 (to the Fig. 2, the reference number 7 shows) about the axis Z4 in the direction of the rotation arrow shown causes an increase in the component of the center distance of the axes Z4 and Z10 that runs perpendicular to the longitudinal axis X and thus a movement of the brake shoe 10 against the inner wall of the inner tube 2. This creates a clamping force between the brake shoe 10 and the inner tube 2, which counteracts and prevents a relative movement of the inner tube 2 and the outer tube 1 via the frictional engagement caused thereby.

[0028] In the Fig. 2 shown, (despite the drawn force arrow F ST) In an unloaded situation, the angle between the longitudinal axis X and the axis distance direction between the axes Z4 and Z10 is in the range of approximately 70-75°, and the brake shoes 10 are already in contact with the inner tube 2 due to a preload force explained below. Since a downward movement of the axis Z4 with the height of the axis Z10 unchanged corresponds to a rotation of the L-link 7 about the axis Z4 that increases this angle, such a virtual movement would move the brake shoes further outwards. Since the size of the support load F ST is the driving force of such a virtual movement, the clamping force increases with increasing support load, so that the support device is suitable for carrying heavy loads up to the range of 1000 kg without the holding force of the locking device being overcome.

[0029] In this embodiment, both the inner tube 2 and the brake shoes 10 are made of aluminum. However, other materials and combinations thereof are conceivable, with preference given to high coefficients of friction.

[0030] Within the pressure bolt 4, another bolt 5 is arranged for longitudinal displacement. A further axis Z5 is arranged through a flange arranged at the lower end of the bolt 5, which also runs transversely to the longitudinal direction X and in particular parallel to the previously described axes Z4 and Z10. Control arms 8 are mounted for rotation about the axis Z5, and are rotatably connected at their other end (axis Z8) to the long end of the L-shaped control arms 7. This control arm-lever arrangement 7, 8 ensures that a relative movement changing the distance between the axes Z5 and Z4 is accompanied by a rotation of the L-shaped control arms 7 about the axis Z4 and thus an increase or decrease, up to and including the release of the clamping force acting via the brake shoes 10.

[0031] A spring 6 is supported on the lower side of the upper end 15 of the bolt 5, the axially opposite end of which rests against a circular ring surface of a recess in the upper region of the pressure bolt 5. The force of the spring 6 opposes a movement of the bolt 5 in the direction of the axis Z4, which opens the locking device. In the Fig. In the position without support load shown in Figure 2, the spring 6 thus causes the pre-clamping force mentioned above.

[0032] The spring strength of the spring 6 is selected such that, on the one hand, the spring force can be easily overcome without tools by applying pressure to the upper end 15 of the bolt 5. On the other hand, it is so high that, if the inner tube 2 were missing, the L-shaped links 7 would still rotate by an additional angle around the axis Z4, but to a maximum total angle of 90° - ε between the longitudinal axis X and the axis distance direction between the axes Z4 and Z10, whereby the safety margin ε is provided before the maximum extended position is reached. Compliance with this safety margin ε is ensured by the spacer bushing 9, which is arranged around the axis Z8 and prevents further rotation of the L-shaped links 7 around the axis Z4 by abutting against the flange of the bolt 5 carrying the axis Z8. An opening movement is limited by the stop of the upper end 15 of the bolt 5 (with a larger diameter than that of the bolt 5) on the fully compressed spring.

[0033] Adjusting the height of the support device is therefore particularly simple. By applying a manually applied opening force to the upper end 15 of the bolt 5, the brake shoes 10 are released from the inner tube 2 via the just-described action of the lever arrangement 8, 7, so that the height of the support device can be freely and continuously adjusted. Once this opening force is removed, the set support height is maintained, even if subsequent large loads act on the support device, which increase this holding force (clamping force) beyond the preload force imparted by the spring 6, as described above.

[0034] The invention is not limited to details of the Fig. 2 and Fig. 3 shown lever arrangement 7, 8. Thus, Fig. 3 merely a lever arrangement which is advantageous due to its symmetrical design, in which a respective link 8 is arranged on the side of one brake shoe 10, axially symmetrical to a symmetry plane passing through the longitudinal axis X. The two L-link arms 7 arranged between them could, of course, also be constructed in one piece. To the non-visible side of the Fig. Two control arms 8 are also arranged toward the other side, offset further outward by the material thickness of the control arms 8 on the other side. On the Z8 axis, from the inside outward, the spacer bushing 9, two L-shaped control arms 7, and the two control arms 8 are arranged.

[0035] Furthermore, in this preferred embodiment, the brake shoes engage from the inside against the inner tube 2. This means that the clamping force exerted by the movable parts of the locking device acts radially outward with respect to the longitudinal axis X. In another embodiment, not shown, however, external brake shoes connected to the outer tube via links could also be used. The outer tube 1 itself is also not required for the locking mechanism, provided the support load F ST is introduced directly into the pressure bolt 4 and ensures its even sliding in the inner tube.

[0036] As already explained, the locking mechanism can be easily released manually by applying pressure to the bolt 5, which is also referred to as the opening rod. However, depending on the coupling of the support device to the device to be supported, for example a camera track, there is not always enough space to introduce the force into the opening rod 5 directly from above. Suitable force deflection devices for creating an accessible force introduction point are known in the art, and depending on the type of application of the support device, there are no limits to the expert's possibilities. One possibility is described in Fig. 4 shown.

[0037] In this exemplary illustration, the required opening force for the opening rod 5 can also be exerted horizontally with a ramp 16, 17 via the horizontally movable part 17 of the ramp. Fig. 4 also shows a rail 20, the weight of which, in addition to the weight of vehicles moving on the rail, such as camera sleds, is supported by the support device 100. Regarding a possible structural coupling of the support device to the rail, reference is again made to WO 2012 / 016 714 A1, to the content of which reference is made in this regard.

[0038] Such a camera path 200 is in Fig. 5 again in a perspective view. The rails 20 of the track elements of the camera track are connected to each other by adapters 21, whereby in Fig. 6, a male-shaped adapter 21 is shown, which interacts with a corresponding female-shaped adapter (not shown). The conical end of the male part can be seen, which, together with its coupling counterpart, provides centering for the rail connection. On the side opposite the female / male coupling, a flange 22 is provided on the adapter in the axial direction, which is only inserted into a bushing 23 arranged within the rail 20, but is not axially fixed. As can be better seen from Fig. As can be seen in Figure 7, the rail 20, which is made of aluminum, for example, has a protective cover 24 on its running side that is harder than the material of the rail 20 and is made of steel, for example. The protective cover 24, which then forms the actual running surface of the rail, is firmly connected to the adapter 21, for example by a screw connection, but not to the rail 20 itself.

[0039] Preferably, the protective cover 24 is elastic and simply clipped onto the rail 20, allowing it to move axially relative to the rail 20. Due to a clearance Δ between the adapter 21 and the rail 20, the protective cover 24 is thus axially movable relative to the rail 20 and can therefore deform under load. Due to the lack of a fixed connection between the protective cover 24 and the rail 20, both the rail and the protective cover can return to their original state once the load is removed.

[0040] The protective sleeve 24 encompasses the rail 20 circumferentially by more than 180°, so that even in the axial center of the rail, the protective sleeve 24 has a uniformly tight radial fit.

Claims

[1] Camera track (200) with a length-adjustable support device (100), with a clamping force-based locking device (4, Z4, 7, 10) for fixing to a predetermined length, characterized by that the clamping force increases with increasing support load and a movement of the movable brake shoes (10) of the locking device, which directly exert the clamping force and are arranged on both sides of the longitudinal axis (X) of the support device, in the direction of the clamping force is accompanied by a change in the distance of two axes of rotation (Z4, Z10), seen perpendicular to the longitudinal axis (X), of which one axis of rotation (Z4) is firmly connected to the area of ​​the support device which absorbs the support load. [2] Camera path according to claim 1, characterized by a gear (Z4, 7) for transferring the support load F ST into the clamping force F KL in a ratio of F ST / F KL ≤ 1. [3] Camera path according to claim 1 or 2, characterized bya pretensioning device (6, 5, Z5, 8) for pretensioning the locking device in the sense of clamping. [4] Camera path according to one of the preceding claims, characterized by a release device (5, Z5, 8) for releasing the locking device. [5] Camera path according to one of the preceding claims, characterized by a limiting device (9) for limiting the adjustment of the gear for converting the support load into the clamping force. [6] Camera track according to one of the preceding claims, with a protective device (24) on the running surface, wherein the protective device (24) is displaceable in the longitudinal direction by a predetermined amount with respect to the rail (20). [7] Camera path according to claim 6, characterized by that the protective device (24) has a greater surface hardness than the rail (20). [8] Camera path according to claim 6 or 7, characterized bythat the protective device (24) is fastened to a coupling device (21) which couples two rails following one another in the longitudinal direction and which is longitudinally displaceable by a predetermined amount with respect to the two rails. [9] Camera path according to one of claims 6 to 8, characterized by that the protective device (24) is elastic. [10] Camera path according to claim 9, characterized by that the protective device (24) is clipped onto the rail (20).

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