WO2009094978A1

WO2009094978A1 - Locking device

Info

Publication number: WO2009094978A1
Application number: PCT/DE2009/000048
Authority: WO
Inventors: Alexander Eck
Original assignee: Wittenstein Ag
Priority date: 2008-02-01
Filing date: 2009-01-16
Publication date: 2009-08-06
Also published as: DE102008007421A1

Abstract

The invention relates to a locking device (04, 45) for fixing a package (02, 46) in the loading room (03) of an aircraft (01), wherein the locking device has a locking element (08, 47) which engages, particularly in a fixing recess (09), for the purpose of fixing the package, and wherein the locking element can be adjusted between a locking position, in which the locking element engages in a fixing manner, and a non-engaged position, in which the locking element is not engaged, and wherein the locking element is pretensioned in the locking position by a mechanical tensioning device (15, 55), and wherein if the load on the locking element exceeds a prespecified threshold, the locking device is automatically released and the locking element automatically moves to the non-engaged position, wherein the locking element can be displaced along a first displacement path section (27) between the locking position (29) and a release position (30), and subsequently along a second displacement path section (28) between the release position (30) and the non-engaged position (33), wherein the locking element engages with the package in a fixing manner along the first displacement path section, and wherein the locking element disengages along the second displacement path section, and wherein the pretensioning device applies a fixing force (26) along the first displacement path section to the release position with a substantially constant force progression corresponding to the load threshold.

Description

locking device

The invention relates to a locking device for fixing a freight item in the cargo hold of an aircraft according to the preamble of claim 1.

Generic locking devices are used to fix cargo in the hold of an aircraft. The cargo, which is loaded on a pallet, for example, is positioned for air transport in the cargo hold of the aircraft and then fixed with one or more locking devices in the desired position. For fixing the freight item, a locking element is provided on the locking device, which is adjustable between a locking position and a disengaged position. In the locking position of the locking element this comes in a Fixierausneh- tion, for example in a recess or depression of a pallet, fixing for engagement. In the disengaged position, on the other hand, the locking element does not engage in the fixing recess so that the freight piece can again be moved in the hold.

Generic locking devices are characterized in that they are not only suitable for fixing the cargo in the hold, but also allow the discharge of the cargo during the flight from a hatch of the aircraft. In this dropping of cargo usually landing parachutes are attached to the cargo. During the actual dropping of the freight The landing parachute is deployed from the hatch and unfolded by the flying wind. As soon as the landing parachute has sufficiently deployed due to the flying wind, a pulling force is transmitted via a pull rope to the freight item, which pulls the freight item out of the loading space through the opened hatch.

Of great importance for the problem-free ejection of the packages with landing parachutes is that the landing parachutes sufficiently unfold before loosening the cargo from the hold. Otherwise there is the danger that the parachute will fall out of the hatch when the landing parachute is not yet deployed

Soil crashes, making impossible the proper deployment of the landing parachute. To ensure this, a mechanical biasing means is provided in generic locking devices, with which the locking element is biased in the locking position. Only when a load threshold which is defined by the pretensioning force of the pretensioning device and with which the locking element is loaded, the locking device then automatically triggers, so that the locking element automatically transitions to the disengaged position and the freight thus released leaves the loading space of the aircraft through the loading hatch can. By means of the load threshold defined by the pretensioner, it is thus ensured that the freight item can not leave the loading space until there is sufficient tension on the traction cable between the freight item and the landing parachute and thus the landing parachute has already exceeded the desired level of deployment.

When fixing a freight item in the hold usually several locking devices are engaged for fixing, so that the total load threshold, which must be exceeded until the freight is triggered, results from the addition of the fixing forces applied by the various locking devices. This additive fixing force leads to a problem that is known in the art as Due to the clearance necessary between the locking element of the individual locking devices and the respectively opposite fixing recesses, it may happen that not all locking devices apply their fixing force evenly in a predefined position For example, it may happen that a locking element abuts directly against the wall of the fixing recess at the beginning, whereas other locking devices still have a play of several millimeters between the locking elements and the walls of the fixing recesses low load, which is far below the desired total load threshold for releasing the cargo, is already sufficient to trigger the individual interlocking devices one after the other The result is then not the desired addition of the multiple fixing forces and the package is pulled out at a level of development of the landing parachute from the hold, which is far below the necessary for the proper discharge degree of development.

To solve this problem, a locking device is known from US 4,379,535, in which the various locking means for fixing a freight item can be adjusted by means of a hydraulic adjusting device after engagement of the locking elements in the Fixierausnehmungen. In this way it is ensured that, after the actuation of the hydraulic adjusting devices, all the locking elements lie positively against the wall of the fixing recess and thus the desired total load threshold is reached by the addition of the load thresholds of the individual pretensioning devices when the freight item is dropped off. A disadvantage of this locking device, however, is the complex structure that is necessary for the realization of the hydraulic adjusting device. Based on this prior art, it is therefore an object of the present invention to propose a new locking device that allows safe dropping of freight items from the hold of an aircraft with a simple structure of the locking device.

This object is achieved by a locking device according to the teaching of claim 1.

Advantageous embodiments of the invention are the subject of the subclaims.

The locking device according to the invention is first of all characterized in that the locking element along a first Stellwegabschnitts between the locking position and a release position and then along a second Stellwegabschnitts between the release position and the disengaged position is adjustable. More Stellwegabschnitte can of course be part of the Gesamtstellwegs between locking position and release position. The first travel path section is precisely characterized in that it is traversed by the locking element before the release position, whereas the second travel path section then adjoins immediately after passing through the release position. Along the first Stellwegabschnitts is the locking element in the fixing device in a fixed engagement and thus brings on the necessary for the fixation of the freight item fixing force. When the triggering position is reached and, as a result, thus driven away, the locking device is automatically triggered and the locking element is disengaged so that the freight item is released and can leave the loading area of the aircraft.

The core idea of the locking device according to the invention is that the biasing device along the first Stellwegabschnitts up to the release position a biasing force with one of the predefined Load threshold corresponding, substantially constant force curve applies. In other words, this means that the fixing force applied by the locking element along the first travel path section until reaching the travel-controlled release position has a substantially constant level. Of course, a constant force curve in the sense of the invention does not mean that the fixing force does not change along the first travel path section at all. Rather, a Fixierkraftverlauf within a narrow tolerance band of, for example, +/- 10% compared to a predetermined average value as a constant force curve in the context of the invention is considered. Due to the constant application of the fixing force along the first Stellwegabschnitts until reaching the release position is achieved that not individual locking devices are already triggered, while other locking devices due to the game between see locking element and Fixierausnehmung nor carry any load. Rather, by appropriate tuning of the length of the first Stellwegabschnitts can be achieved that after passing through the first Stellwegabschnitts to the locking device, the first load transmits on the freight piece for engagement, the game between locking elements and Fixierausnehmungen is passed through all locking devices, so that in Result then gives the desired total addition of all the locking devices applied by the fixing forces before the release of the first locking means and the necessary total load is achieved until the release of the freight item.

With which machine elements the biasing device of the locking device is realized, is basically arbitrary. Particularly simple and inexpensive, the necessary clamping force can be applied with a prestressed tension spring. However, such tension springs have their usual characteristic after an increasing

Spring force characteristic, so that in the result without further measures applied by the tension spring resulting fixing force along of the first Stellwegabschnitts would increase. In order to be able to use tension springs for the locking device according to the invention in spite of this increasing load characteristic, a transmission gear can be provided between the tension spring and the locking element whose force transmission characteristic in the superposition with the tension spring characteristic results in a fixing force profile which is constant in the working range along the first travel path section.

According to one aspect of the locking device according to the invention, the locking element is triggered away after passing through the first Stellwegabschnitts in a triggering position. In order to realize such a controlled release of the locking element in a simple manner, the locking element along the two Stellwegabschnitte can be forcefully positively guided in a sliding guide.

The release position of the locking element can then be defined in particular by an arc of the slotted guide.

As already explained above, the length of the first travel path section, along which a substantially constant fixing force is applied by the locking element, enables clearance compensation on all locking devices for fixing a freight item during deployment by means of a landing parachute. The length of the first Stellwegabschnitts is thus on the usually existing game, which is required when locking the locking elements in the Fixierausnehmun- match. Conversely, of course, a relatively short first Stellwegabschnitt is desired because with the length of the first Stellwegabschnitts the design effort for the realization of a substantially constant force curve of the fixing increases. For the practical operation of generic locking devices, therefore, a length of the first Stellwegabschnitts in the range of 6 to 14 mm, in particular a length of 10 mm, as in terms of the game to be compensated and in terms of effort for Realization of the constant force curve of the fixing force proved to be a good compromise.

The design of the transmission gear for transmitting the biasing force to the locking element is basically arbitrary, as long as the superposition of the power transmission characteristic of the transmission with the spring force characteristic of the tension spring in the work area along the first travel constant force curve can be realized. This can be realized in a particularly simple and cost-effective manner by using multi-joint transmissions, in particular by using a toggle mechanism. Such toggle gear, for example, have a hyperbolic power transmission characteristic, the working range of the toggle mechanism is meaningfully chosen so that a portion of the hyperbolic force transmission characteristic is selected with a substantially linearly decreasing power transmission. This in the work area substantially linearly sloping power transmission characteristic allows in a very simple manner a compensation of the linearly rising spring force line, so that the result of the superposition results in a substantially constant force curve.

In order to avoid disturbances of the dropping of the freight item and to facilitate the reloading of the aircraft, the locking element should remain fixed in its release position after the automatic release. For this purpose, a fixing device, such as a fishing hook or the like may be provided in the locking device, with which the locking element is fixed in its release position and thus a spring back of the locking element is excluded in the locked position even after leaving the freight item.

In order to reduce the number of components of the locking device, it is particularly advantageous if the fixing of the locking element in the release position by a lever of the multi-joint transmission, which is anyway kinematically connected to the locking element is realized. In order to be able to set the load threshold of the individual locking devices until the locking element is triggered and thus the total load threshold until the freight piece is released from the cargo space of the aircraft, an adjustment device can be provided on the locking device with which the gradient of the spring force characteristic of the tension spring and / or or the slope of the power transmission characteristic of the transmission gear is adjustable. As a result, the fixing force acting on the locking element in the working area can be changed along the first travel path and thus matched to the requirements of different load-release procedures, and in particular different sizes of landing parachutes.

In order to adjust the slope of the spring force characteristic, it is structurally particularly advantageous if the two bearing points of the tension spring between which the tension spring is biased, can be changed relative to each other in position with the adjustment. By this change in stock, it is firstly possible to change the direction of force introduction of the tension spring in the transmission gear and thus the effective force component, with which the tension spring acts effectively on the transmission gear set. On the other hand, the distance between the bearing points and thus the biasing force of the tension spring can be changed by the change in bearing between the two bearing points.

In order to be able to make a setting of the adjusting device also remotely controlled, the adjusting device may comprise a drive spindle with a drive motor, wherein the second bearing point is mounted on the drive spindle. By rotational drive of the drive spindle then the position of the second bearing point can be changed relative to the first bearing point and thus the desired setting can be made.

If the force introduction direction of the spring loaded by the pretensioning spring on the transmission gear is to change the spring force characteristic brought biasing force be adjustable, so it is particularly advantageous if the second bearing point is adjustable on a circular line relative to the first bearing point. Due to the circular course of the travel ensures that along this travel not also the distance between the two bearing points changed, which would lead to an undesirable interference effect.

Alternatively or in addition to the adjustment of the force introduction direction and the distance between the two bearing points can be changed.

In at least one position of the two bearing points of the tension spring, the tension spring should apply no spring force to the transmission gear and thus pass the locking element unloaded into the disengaged position. This relative position of the two bearing points is then referred to as a relief position and can be used for manual or remote unlocking of the locking device.

Various aspects of the invention are shown in partial schematic form in the drawings and are explained by way of example below.

Show it:

1 shows a schematically illustrated aircraft during the discharge of a freight item from the air using a landing parachute;

FIG. 2 shows a locking device for fixing a freight item in the cargo hold of the aircraft according to FIG. 1 in the locking position; FIG.

3 shows the locking device according to FIG. 2 shortly before reaching the release position of the locking element; FIG. 4 shows the locking device according to FIG. 2 shortly before reaching the disengaged position of the locking element;

FIG. 5 shows the force curve of the fixing force applied to the locking element by the locking device according to FIG. 2 along the first and second travel path section; FIG.

6 shows the force curve of the freight item in the aircraft according to FIG. 1 of the four locking devices in total applied fixing force.

7 shows the locking device according to FIG. 2 after adjustment of the spring force characteristic curve by means of an adjusting device;

FIG. 8 shows the locking device according to FIG. 7 after setting a second spring force characteristic; FIG.

9 shows the locking device according to FIG. 7 in its load-free unloading position; FIG.

10 shows a schematically illustrated second embodiment of a locking device in the locking position;

Figure 1 1, the locking device of Figure 10 in a position along the first Stellwegabschnitts ..;

FIG. 12 shows the locking device according to FIG. 10 shortly before reaching the release position; FIG.

FIG. 13 shows the locking device according to FIG. 10 shortly after passing through the release position; FIG.

Fig. 14, the locking device of FIG. 10 in its disengaged position.

FIG. 1 schematically illustrates an aircraft O 1 during the discharge of a freight item 02 during the flight. The freight item 02 is located in FIG Cargo space 03 of the aircraft O l and is fixed there with four locking devices 04 in the X direction, which corresponds to the direction of flight.

To discharge the freight item 02 from the air is a landing parachute 05 which is connected to the freight item 02 via a pull line 06. Once the landing parachute 05 is dropped by the opened hatch 07, he unfolds and brings due to the high air resistance a tensile force on the pull line 06 on the freight piece 02 on. The locking devices 04 each engage with locking elements 08 in fixing recesses 09 of the freight item 02, for example an air landing pallet, and can have a fixing force with a predefined one

Apply threshold. Only when the pulling force applied by the pulling line 06 exceeds a total load threshold which corresponds to the addition of the individual load thresholds applied by the four locking devices 04 does the freight piece 02 come off and can be pulled out of the hold 03 by the landing hatch 07 against the flight direction by the landing parachute 05 become.

Fig. 2 shows the locking device 04 when fixing the freight item 02 in an enlarged view. The locking element 08 engages in the Fixierausnehmung 09 of the freight item 02, wherein between the length of the locking element 08 and the length of the Fixierausnehmung 09 is an essential game to allow the proper locking of the locking device 04 on the package 02 under practical conditions. The basic mechanical structure of the locking device 04 is formed by two mutually parallel plates 10 and 1 1, wherein in the representations of FIG. 2 to FIG. 9, the upper plate 1 1 is shown transparent for better visibility of the internal components. The locking element 08 is mounted with two laterally projecting stud bolts 12 and 13 in a slotted in the plates 10 and 1 1 link guide 14 longitudinally displaceable. When the stay bolts 12 and 13 bear against the front stop of the guide slot 14, the locking element 08, as shown in FIG its locking position and can fix the freight item 02 in its cargo position by applying a fixing force in the Fixierausneh- tion 09.

The locking element 08 in turn is supported by a biasing device 15, which consists of a tension spring 16 and a toggle mechanism 17, for applying the fixing force. The toggle mechanism 17 consists of an L-shaped first lever 18 and an arcuate second lever 19, wherein the lever 18 is pivotally mounted with its one end to the plates 10 and 1 1 and the lever 19 hinged at its outer end to the underside of Bar element 08 is articulated. The two levers 18 and 19 are in turn hinged together. At the lower end of the one arm of the L-shaped lever 18, the tension spring 16 engages and presses the toggle mechanism 17 in the direction of the toggle dead center. The fixing force applied by the locking element 08 thus results from the superposition of the tension force applied by the tension spring 16 and the force transmission characteristic defined by the toggle mechanism 17.

To adjust the applied force of the tension spring 16 clamping force is in the plates 10 and 1 1, a second slotted guide 20 is cut. The tension spring 16 is biased between the two bearing points 21 and 22, wherein the lower bearing point 22 is adjustably mounted in the slotted guide 20. For remotely controllable adjustment of the lower bearing point 22, this is mounted on an adjusting nut 23 which can be adjusted by rotary drive on a drive spindle 24. The rotary drive of the drive spindle 24 is realized by a pivotally mounted between the plates 10 and 1 1 drive motor 25.

FIG. 3 and FIG. 4 show the locking device 04 during the discharge of the freight item 02. As shown in FIG. 3, the locking element 08 is opened by the tension line 06 on the freight item 02. ten tensile forces loaded and thereby pressed in the slotted guide 14 along a first Stellwegabschnitts 27 from the locking position shown in Fig. 2 in the direction of the release position. Fig. 3 illustrates the locking element 08 shortly before reaching the release position, which is defined by the arc of the rear slide guide 14a, as soon as the stud bolt 13 has reached the arc of the slide guide 14a, the fixation force transmitted by the toggle mechanism 17 abruptly drops and the locking element 08 goes into the disengaged position. 4, the locking device 04 is shown shortly before reaching the non-engaged position of the locking element 08. When the non-engaged position of the locking element 08 is finally reached, the lever 19 is pressed upwards by the lever 18 under the pressure of the tension spring 16 until the concave arc side of the lever 19 locks the locking element 08 in the disengaged position. At the latest in the disengaged position of the locking element 08, the freight item is free and can be pulled out of the cargo compartment 03 without resistance of the locking device 04.

5 shows schematically and by way of example the force curve 26 of the locking element 08 applied to the freight piece 02 fixing force along the first Stellwegabschnitts 27 and the second Stellwegabschnitts 28. Between the locking position 29 and the release position 30 of Fixierkraftverlauf 26 is substantially constant between an upper tolerance threshold 31 and a lower tolerance threshold 32. As soon as the locking element 08 has reached the release position 30, the force curve 26 drops from this level corresponding to a predefined load threshold to the zero value which is reached at the latest, but possibly also earlier, when the disengaged position 33 is reached. The substantially constant force level of the force curve 26 along the first Stellwegabschnitts 27 results from the superposition of the spring force characteristic of the tension spring 16 and the force transmission characteristic of the toggle joint 17th Fig. 6 illustrates the Gesamtfixierkraftverlauf 34, which is applied by the four locking devices 04 in addition, the discharge of the freight piece 02 by means of landing parachute 05 schematically and by way of example. As soon as a first train on the freight piece 02 is applied via the pull line 06, this is initially tightened until the first locking device 04 comes with its locking element 08 without play in the Fixierausnehmung 09 to the plant. At this time, the total fixing force counteracting the pulling force in the pulling line 06 increases significantly in a first step 35. According to the characteristic of the locking device 04 according to the invention, the Gesamtfixierkraftverlauf 34 then initially substantially constant until even at the second locking device, the clearance between the locking element 08 and 09 Fixierausnehmung is compensated and the second locking device 04 can transmit their fixing force on the freight piece 02 due to the positive connection. At this moment, the Gesamtfixierkraftverlauf 34 then increases again in a second stage 36, wherein the height of the steps 35 and 36 respectively corresponds to the load thresholds of the individual locking devices 04. Upon further pulling on the pulling line 06 and further piecewise displacement of the freight item 02, the third and the fourth locking device then also engage positively in the fixing recesses 09 so that the total fixing force in two further stages 37 and 38 is limited to a predetermined one Total load threshold 39 increases. The total fixing force no longer increases above this value since the fixing forces applied by the individual locking devices 04 are constant in each case.

When the first locking device 04, whose fixing force corresponds to the first level 35 of the total fixing force 34, reaches its release position 40, the total fixing force curve 34 drops significantly as a result of triggering this first locking device 04, so that subsequently the freight piece 02 increases due to the tensile force applied in the pulling line 06 is accelerated and then in quick succession, the three remaining locking devices 04 are triggered shortly after one another. However, due to the force course of the four fixing locking devices 04, which remains essentially constant along the first travel path section 27, it is ensured that the total fixing force 34 corresponds to the desired total load threshold value 39 in a travel path section 41 shown hatched, although due to the play between the individual locking elements 08 and the associated Fixierausnehmungen 09 not all locking devices 04 at the same time load transferring come on the freight piece 02 for engagement. The length of the first Stellwegabschnitts 27 is therefore just to vote on the expected game between the locking elements 08 and the Fixierausnehmungen 09 that results in a sufficiently long Stellwegabschnitt 41 with reliably applied Gesamtlastschwelle 39.

Fig. 7 and Fig. 8 show the locking device 04 in the adjustment of the spring force characteristic for adjusting the attachable force profile of the locking element 08 can be applied. By rotational drive of the drive motor 25, the lower bearing point 22 can be adjusted relative to the upper bearing point 21 along a circular arc-shaped path, so that the force introduction direction of the tension spring 16 at the toggle joint 17 changes accordingly. Due to the thus changing angular conditions, the tension force transmitted by the tension spring 16 effectively to the toggle joint 17 changes accordingly.

In the position shown in Fig. 8, the tension spring 16 extends almost parallel to the lever 18, so that effectively almost no clamping force is transmitted from the tension spring 16 in the toggle joint 17. In this position, in the slotted guide 20 is followed by a substantially parallel to the course of the lever 18 extending section.

9 shows the adjustment of the bearing point 22 in the end portion of the slotted guide 20. In this case, the distance between the bearing points 21 and 22 is increased until the tension spring 16 is finally fully completed. dig is relieved and thus the locking element 08 passes into its unloaded unloading position.

10 to 14 show a second embodiment 45 of a locking device according to the invention when triggered by moving a freight item 46 shown merely schematically. In FIG. 10, the locking element 47 is in its locking position, which is defined by the demanding end of the sliding guide 48a and 48b is. A biasing means 55, namely a tension spring 49, presses a toggle joint 50 with the levers 51 and 52 in the direction of the upper toggle dead center and thus defines the fixing force that can be applied by the locking element 47 on the freight piece 46.

If the freight piece 46 is now pulled in the direction of the discharge, then, as shown in Fig. 1 1, the locking element 47 in the slotted guides 48a and 48b rearwardly adjusted, wherein the locking element 47 applied to the freight piece 46 fixing force by superimposing the tension spring characteristic and the force transmission characteristic remains substantially constant.

Fig. 12 shows the locking device 45 shortly before reaching the release position of the locking element 47, which is defined by the lower arc of the slotted guide 48a. If this release position is exceeded by further pulling on the freight piece 46, then the locking device 45, as shown in FIG. 13, automatically moves into the disengaged position shown in FIG. In this disengaged position, the locking element 47 is locked by positive engagement between the lever 52 and the stud bolt 53 for guiding the locking element 47 in the

Slotted guide 48a fixed. By complete relief of the tension spring 49, the toggle joint 50 can then then be lowered so far until the lever 52 releases the stud 53 again and by re-tensioning the tension spring 49, the locking element 47 is brought back into its locking position shown in Fig. 10. LIST OF REFERENCE NUMBERS

Aircraft 33 Non-engagement position Freight 34 Total Fixing Force Cargo Area 35 First Stage Locking Device 36 Second Stage Landing Parachute 37 Third Stage Tug Leash 38 Fourth Stage Cargo Lift 39 Total Load Threshold Locking Element 40 Total Release Position Fixing Slot 41 Travel Section Plate 45 Locking Device Plate 46 Carriage Studs 47 Locking Element Studs 48 Cam Guide Cam Guide 49 Tension Spring Tension Device 50 Toggle Mechanism Tension Spring 51 Lever Knee lever gear 52 Lever Lever 53 Stud Lever 54 Stud bolt Cam guide 55 Pretensioner Bearing point Bearing point Adjusting nut Drive spindle Drive motor Fixing force First travel path section Second travel path section Locking position Release position Upper tolerance threshold Lower tolerance threshold

Claims

claims

1. locking device (04, 45) for fixing a freight item (02, 46) in the cargo space (03) of an aircraft (Ol), wherein the locking device (04, 45) has a locking element (08, 47), which is for fixing to the freight item (02, 46), in particular in a fixing recess (09), comes into engagement, and wherein the locking element (08, 47) between a locking position in which the locking element (08, 47) is fixedly engaged, and a Nichtein - Handle position in which the locking element (08, 47) is not engaged, is adjustable, and wherein the locking element (08, 47) by a mechanical biasing means (15, 55) is biased in the locking position, and wherein when a defined Load threshold with which the locking element (08, 47) is loaded, the locking device (04, 45) is automatically triggered and the locking element (08, 47) automatically goes into the disengaged position, characterized in that the Rie gel element (08, 47) along a first Stellwegabschnitts (27) between the locking position (29) and a release position (30) and thereafter along a second

Stellwegabschnitts (28) between the release position (30) and the disengaged position (33) is adjustable, wherein the locking element (08, 47) along the first Stellwegabschnitts (27) fixing the freight piece (02, 46) is engaged, and wherein the Riegelele - ment (08, 47) along the second Stellwegabschnitts (28) is disengaged, and wherein the biasing means (15, 55) along the first Stellwegabschnitts (27) to the release position (30) a fixing force (26) with one of the load threshold corresponding, substantially constant force course applies.

2. Locking device according to claim 1, characterized in that the biasing means (15, 55) comprises a prestressed tension spring (16, 49) and a transmission gear (17, 50), wherein the transmission gear (17, 50) of the tension spring (16 , 49) transfers applied spring force with a defined force transmission to the locking element (08, 47).

3. Locking device according to claim 1 or 2, characterized in that the tension spring (16, 49) has along the first Stellwegabschnitts (27), in particular substantially linear, increasing spring force characteristic, and the transmission gear (17, 50) along the first one Stellwegabschnitts (27), in particular substantially linear, falling force transmission characteristic curve, wherein the superimposition of the spring force characteristic and the force transmission characteristic in the working area along the first Stellwegabschnitts (27) to the release position (30) corresponding to the load threshold, substantially constant force curve of the fixing force (26 ).

4. Locking device according to one of claims 1 to 3, characterized in that the locking element (08, 47) by a sliding guide (14, 48) along the first and second Stellwegabschnitts (27, 28) positively positively guided.

5. Locking device according to claim 4, characterized in that the release position (30) by an arc of the slotted guide (14, 48) is defined.

6. Locking device according to one of claims 1 to 5, characterized in that the first Stellwegabschnitt (27) has a length in the range of 6mm to 14mm, in particular a length of 10mm.

7. Locking device according to one of claims 1 to 6, characterized in that the transmission gear (17, 50) is designed in the manner of a multi-link transmission.

8. Locking device according to claim 7, characterized in that the multi-link mechanism in the manner of a toggle mechanism (17, 50) is formed.

9. Locking device according to one of claims 1 to 8, characterized in that the locking element (08, 47) with a fixing device in the

Trigger position is fixable.

10. Locking device according to claim 9, characterized in that the locking element (08, 47) by a lever (52) of the multi-steering gear (17, 50) in the release position can be fixed.

1 1. Locking device according to one of claims 1 to 10, characterized in that on the locking device (04) the slope of the spring force characteristic of the tension spring and / or the slope of the force transmission characteristic of the transmission with an adjustment (23, 24, 25) is adjustable ,

12. Locking device according to claim 1 1, characterized in that the tension spring (16) between a first bearing point (21) on the transmission gear (17) and a second bearing point (22) on the adjusting device (23, 24, 25) is biased, wherein for adjusting the pitch of the spring force characteristic with the adjusting device (23, 24, 25) the position of the second bearing point (22) relative to the first bearing point (21) is variable.

13. Locking device according to claim 12, characterized in that the adjusting device (23, 24, 25) with a drive motor (25) drivable drive spindle (24), on which the second bearing point (22) with an adjusting nut in its position relative to first bearing point (21) is adjustably mounted.

14. Locking device according to claim 12 or 13, characterized in that the second bearing point (22) on a circular line relative to the first bearing point (21) is adjustable.

15. Locking device according to one of claims 12 to 14, characterized in that the distance between the second bearing point (22) and the first bearing point (21) is variable.

16. Locking device according to one of claims 12 to 15, characterized in that the second bearing point (22) can be brought into a relief position in which of the tension spring (16) no spring force on the transmission gear (17) is applied and the locking element (08 ) passes unloaded into the disengaged position.