WO1999041509A1

WO1999041509A1 - Telescopic support

Info

Publication number: WO1999041509A1
Application number: PCT/EP1999/000634
Authority: WO
Inventors: Werner Adolf Betzenhofer
Original assignee: Werner Adolf Betzenhofer
Priority date: 1998-02-11
Filing date: 1999-02-01
Publication date: 1999-08-19
Also published as: DE19805474C1; AU2923499A

Abstract

The invention relates to a telescopic support (1), comprising a telescopic cylinder (4) and a telescopic rod (5), in addition to manually actuated advancement means for stagewise extension of the telescopic rod (5) from the telescopic cylinder (4). The advancement means comprises a handle (16; 32; 42; 48) with a force-transmitting block (15; 37; 44) that is pivotally mounted on the telescopic rod (5). According to the invention, the handle (16; 36; 42; 48) is movably mounted on the force-transmitting block (15; 37; 44) and is coupled to the latter by at least one spring element (17; 40; 46) so that during manual actuation, the spring element (17; 40; 46) is displaced along a spring path in correspondence with the dimension of the actuation force. During an initial unacceptable overload of the telescopic support (1) and/or a component used resulting from an overload actuation force exerted on the handle (16; 36; 42; 48), an allocated spring path threshold value for an overload spring path is exceeded at least by part of the spring element (17; 40; 46). Overload signaling means (20; 38; 45) serving as overload protection can be activated by the assigned relative position between one part of the spring element and the handle (16; 36; 42; 48) or the force-transmitting block (15; 37; 44) and/or by the assigned relative position between the force-transmitting block (15; 37; 44) and the handle (16; 36; 42; 48).

Description

description

Telescopic support

The invention relates to a telescopic support according to the preamble of claim 1.

Telescopic supports are generally known in a variety of embodiments and are used in many areas such. B. used as tent supports, for supporting awnings, for height-adjustable tables and other objects, for shelf supports and for clamping between the floor and ceiling of a room and as a jack. Furthermore, telescopic supports are used as aids for the assembly of ceiling cladding, roof battens, machine parts or the like in order to facilitate this work or to enable it for one person at all.

All such telescopic supports consist of at least one or more telescopic tubes and telescopic rods which can be telescoped into one another and can be locked in different extension lengths by locking means. For example, a known telescopic support (US Pat. No. 3,734,441} is locked against being pushed in and pushed out by two actuatable locking plates.

There are also telescope supports with hand-operated feed means in many embodiments generally known, such hand-operated feed means ratchets, racks, clamps or 2 can be the same. Such feeds with clamping brackets consist in particular of an actuatable locking plate and a further actuatable feeding plate, through which a telescopic rod is guided and which can be brought spring-loaded from a tilted locking position into a release position. In the tilted locking position, the feed plate can also be gradually adjusted in the extension direction together with the telescopic rod, the locking plate being pressed into its release position. Such feeds are generally known from simple tools, such as from cartridge presses. In connection with telescopic supports, they are generally known from an embodiment of a jack that was previously widely used (eg VW jack). With telescopic supports as assembly aids, such manually operable feed means are also known (DE 296 05 222 Ul; DE 296 01 103 Ul).

Such telescopic supports as assembly aids should on the one hand be light in weight and on the other hand be relatively inexpensive to manufacture. This means that the telescopic support as a whole and the individual parts have only a limited, predetermined stability and can be damaged and destroyed in the event of an overload. This overload can usually be achieved due to the relatively large leverage with operational, powerful manual operation, so that the feed means then have destructive effects on the mechanical components and / or the pipes or rods. This can lead to considerable damage to the telescopic support in connection with a sudden yielding and retracting and carries a considerable risk of accidents if supported parts fall down on a user when the overload control is operated and the telescopic support is damaged.

A known telescopic support with gradual displacement by a gill mechanism consisting of a locking plate and a feed plate (DE-OS 27 20 948) solves the problem of impermissible overloading by 3 given, maximum extended end position the feed comes out of engagement. Such overload protection is only possible with a fixed extension path against a stop and cannot be used with telescopic supports as working aids with operationally different extension paths.

Furthermore, automatically extending telescopic supports are known, in which prestressable extension means are contained in the telescopic tube area when the tubes are pushed together. In a known embodiment (DE 40 36 970 AI), a combination of band springs and spiral compression springs is used for this. In another known embodiment, a gas spring that can be locked in different positions is used (DE 195 29 989 AI). In a generic embodiment (DE 296 05 222 Ul), a combination of a manually operable feed means for a gradual feed and a compression spring is used. The disadvantage here is that when the telescopic support and the prestressed compression spring are pushed together, there is a risk of this automatic feed being triggered automatically and unintentionally, and there is therefore an increased risk of accidents.

In the case of telescopic supports, it is also already known to mount support feet and support plates in a partially interchangeable manner on the two end sides. Ball joints used lead to problems with the stability of the telescopic support. Alternately used screw connections for connecting specially shaped end parts to the telescopic support ends can only be changed with great effort using a tool.

The object of the invention is to provide a telescopic support in which an overload can be identified and avoided. 4 This object is achieved with the characterizing features of claim 1.

According to the characterizing part of claim 1, the handle is movably mounted on the power transmission block. The handle is also coupled to the power transmission block by a spring element in such a way that, when operated manually, the spring element is deflected with a spring travel corresponding to the size of the operating force. If the telescopic support and / or the components used are inadmissibly overloaded according to an overload actuating force on the handle, an assigned spring travel threshold to an overload spring travel is exceeded at least by part of the spring element. After this spring travel threshold is exceeded and an overload spring travel is present, an overload signaling means is activated as overload protection. For this purpose, the assigned relative position between a spring element part and the handle or the power transmission block can be used. Alternatively or additionally, the assigned relative position between the power transmission block and the handle can also be used to determine an overload spring travel.

This advantageously means that the user of the telescopic support is signaled that an overload is beginning, with the request that the feed means no longer be operated. This prevents damage to the telescopic support and / or the components used, and the associated accident risks for a user, since no critical overload has yet been reached when the overload signaling occurs.

For unintentional users who ignore this overload signaling, it is proposed in a continuation of the overload protection according to claim 2 that the spring element with extreme overload actuation with imminent risk of breakage and damage from a loading 5 agreed overload path is plastically deformable in such a way that with a then deformed spring element, the force transmission block can no longer engage in a force-transmitting manner in the drive of the feed means. In this case, which can not occur when the telescopic support is used correctly and the overload signaling is observed, it is expedient to arrange the spring element in a simply replaceable manner.

In a particularly preferred, simple and inexpensive to produce embodiment according to claim 3, the spring element is a leaf spring, which is supported from a free end of the handle on the power transmission block preferably in a slot there and bulges in the direction of the inner surface of the handle when actuated. An overload signaling bolt is arranged approximately in a central region of the leaf spring and, when a predefined spring travel threshold is exceeded, emerges from a handle opening, preferably approximately in a central region of the hand support surface. Since a user of the telescopic support has to actuate the handle vigorously especially when an overload begins, he clearly notices the emerging overload signaling bolt in the palm of his hand. In the case of an overload signaling bolt with a small diameter and a rounded tip, a can also be deliberately used

Pain is generated so that the user is prevented from further manual operation. The leaf spring used here can also be easily dimensioned so that the above-mentioned extreme overload. plastic deformation occurs. In this embodiment, the handle, the power transmission block and the leaf spring can be integrated particularly easily and in a space-saving manner in a single handle part.

In alternative embodiments according to claims 4 and 5, overload signaling is also possible by means of an overload signaling bolt on the power transmission block or by sensor elements in conjunction with acoustic and / or visual alarm devices. 6 In principle, the overload signaling described above and also the overload protection can be implemented by plastic deformation of the spring element in all known feed means, which are driven in particular by pumping movements of a handle. Generally, according to claim 6, ratchet arrangements, rack arrangements with pawls or clamping arrangements are known and can be used as feed means. A feed device known per se and described at the outset is particularly suitable as a clamping arrangement with a manually operable locking plate and a feed plate on which a nose of the power transmission block engages, whereby the extension drive thus formed can be actuated in stages with pump movements of the handle. Such a feed means can be produced in a particularly simple, inexpensive and inexpensive manner in connection with the above overload protection.

In addition to the overload-protected, manually operated extension drive, the telescopic support is preferably equipped with a further extension drive as a spring drive. For this purpose, a tension spring is contained in the telescopic tube, which can be inserted and connected in a detachable manner at the lower end, preferably via a block part, to the lower end of the telescopic rod and is connected at the upper end to an upper region of the telescopic tube. The tension spring is thus pulled out when the telescopic rod is pushed in and pre-tensioned for an automatic extension. In the upper area of the telescopic tube there is a hand-operated, spring-loaded spring drive locking plate, which locks the spring drive in the unactuated state. Such a tension spring has the particular advantage that the contact between the lower end of the telescopic rod and the lower end of the tension spring allows the telescopic rod to be extended further from the area of the relieved tension spring by relinquishing the contact connection. So that the telescopic rod cannot be fully extended, there is a pressure at its lower end. 7 The anti-lock washer is integrated at the lower end above the compression of the telescopic rod so that it does not become jammed and jammed when the system has a maximum permissible extension path.

With the features of claim 9 it is achieved that the spring drive locking plate with the power transmission block and thus by the handle after a short actuation can be transferred to its release position for an automatic extension. Thereafter, it is held in its release position over a circular link surface on which the wide angle leg plate lies tangentially and which therefore does not cause any further adjustment of the spring drive locking plate, the pumping movements of the handle then being possible for the gradual manual extension. This enables an advantageous one-hand operation via the handle for both extension drives. Due to the angular design of the spring drive locking plate, an effective locking of the telescopic arrangement with a prestressed tension spring is also possible, in which a fixing of the spring drive locking plate in its locking position by a locking bolt is preferably possible as a pipe clip connector. This significantly increases operational safety and reduces the risk of accidents, since the spring-loaded telescopic support cannot expand unexpectedly and unintentionally.

The telescopic rod can basically be pushed back into the telescopic tube after actuation of the locking plate. In order to facilitate this, claim 11 proposes a hand-displaceable retraction plate with a structure similar to that of the locking plate, the free end of which is designed as a hanging device. Tools, cables, etc. can be hung on the hanging device, which is particularly practical when working on an easel. 8 According to claim 12, the telescopic rod should be polygonal in cross section, preferably as an equilateral hexagon. This will surely prevent the telescopic rod from rotating unintentionally in the support position. The telescopic rod is expediently made from solid material, but depending on the circumstances and the specified permissible vertical load, it can also be tubular.

In principle, the handle with overload protection as well as the feed and locking means can be attached directly to an upper area of the telescopic tube. For manufacturing and construction reasons and for reasons of stability, however, it is advantageous according to claim 13 to attach these parts to a head part of the telescopic tube. Such a head part can overlap the telescopic tube end with a collar in a manner known per se and / or protrude into the telescopic tube with a plug-in part, so that a stable connection exists, which is additionally carried out by measures known per se, such as adhesives, screw connections, rivets, etc. can be strengthened and secured. Alternatively, a head part can also be inserted into the upper tube end and connected there, in which case the tube is to be provided with a lateral longitudinal slot for the attachment and passage of the handle and possibly further actuating elements.

The invention is explained in more detail with reference to a drawing.

Show it:

1 is a schematic representation of a telescopic support in the pushed-together state,

2 shows a schematic illustration of a telescopic support in the exploded state, 9 shows a section through a head part in a non-actuated position of the handle,

4 shows a section through a head part with the handle actuated,

5 shows a section through a handle with a leaf spring as overload protection,

6 shows a schematic illustration of a first alternative embodiment of a handle with a compression spring,

7 shows a schematic illustration of a second alternative embodiment of a handle with a leg spring,

8 shows a schematic illustration of a third alternative embodiment of a handle with a pressure sensor,

9 is a schematic representation of a telescopic support with a spring drive when the tension spring is not tensioned,

10 is a schematic representation of a telescopic support with a spring drive with the tension spring tensioned,

11 is a plan view of a retraction plate with a hanging option,

12 is an illustration of a pipe clip connector that can be inserted into a locking opening of a telescopic tube,

13 is a schematic representation of an assembled pipe linch pin with safety chain, 10 A telescopic support 1 is shown in the pushed-together state in FIG. 1 and in the exploded state in FIG. 2. The telescopic support 1 comprises a telescopic rod 5, which is telescopic in a telescopic tube 4 and has a hexagonal cross section, and a head part 6 for gradually extending the telescopic rod 5 out of the telescopic tube 4.

The partial telescopic tube 4 is constructed in two parts from a first upper telescopic tube part 2 and a second lower telescopic tube part 3, the first upper telescopic tube part 2 telescoping into the second lower telescopic tube part 3. A mutual height adjustment of these two telescopic tube parts 2, 3 is possible by means of a tripod spring 7 with double bolts.

This tripod spring 7 with double bolts is arranged in a lower end of the first upper telescopic tube part 2, the double bolts projecting through opposite openings in the wall of the first upper telescopic tube part 2. Likewise, mutually opposite openings 8 are arranged at different height positions along the second lower telescopic tube part 3. The double bolts of the stand spring 7 also protrude through these openings 8, so that the first upper telescopic tube part 2 can be fixed in a desired height position relative to the second lower telescopic tube part 3.

For a secure stand of the telescopic support 1, a rubber cap 9 is attached to the lower end of the second lower telescopic tube part 3 as an anti-slip covering with a large contact area. If the stability of the telescopic support is reduced due to wear of the rubber cap 9, it can simply be replaced.

While a basic height adjustment can be carried out with the two-part telescopic tube 4, for the final support of e.g. B. a ceiling plate to be fastened, the telescopic rod 5 gradually extended. 11 The structure and function of the head part 6 is explained below, in particular with reference to FIGS. 3 and 4:

The head part 6 is a separate, e.g. Component manufactured by plastic injection molding and plugged onto the first upper telescopic tube part 2 with a lower end 10. The head part 6 has an opening 13 in the longitudinal direction corresponding to the hexagonal cross section of the telescopic rod 5, so that it can only be moved up or down, but not rotated. Above the lower end 10, the head part 6 has a cutout 14 in which the feed means of the telescopic rod 5 are arranged.

A force transmission block 15 is pivotally mounted on the head part 6 in an approximately central region of the cutout 14. A handle 16 is in turn movably mounted on this force transmission block 15 and coupled to the force transmission block 15 by a leaf spring 17. This leaf spring 17 is supported from a free end 18 of the handle in a slot 19 on the power transmission block 15. An overload signaling pin 20 is arranged in the area below a handle opening 21 in a central area of the leaf spring 17.

In an upper region of the cutout 14, a manually operable locking plate 24 is pivotally held on the head part 6. This locking plate 24 has an opening 25 through which the telescopic rod 5 is guided. The locking plate 24 rests with a rear end on a projection 23 and is spring-loaded around the opening 25 by a compression spring 26. 3 and 4, the locking plate 24 is pivoted from the horizontal into an inclined locking position in which it blocks the telescopic rod 5 from being inserted. 12 Furthermore, a feed plate 27 with an opening 28 on the head part 6 is pivotally held in the cutout 14 of the head part 6. When the handle 16 is not actuated, this feed plate 27 is, as shown in FIG. 3, by a compression spring 30 which is supported on the one hand on the feed plate 27 and on the other hand on a projection 29 in a horizontal contact with a projection 31 in the region below the feed plate 27 held. In this horizontal orientation of the feed plate 27, the feed plate 27 for the telescopic rod 5 is freely passable. The projections 29 and 31 are designed in such a way that they respectively open the openings 25 and 28 for the telescopic rod 5 to be pushed through unhindered.

To push out the telescopic rod 5, the handle 16 is transferred from the non-actuation position shown in FIG. 3 to the actuation position shown in FIG. 4. In this case, a nose 32 formed on the power transmission block 15 comes into contact with the feed plate 27 and, in cooperation with the compression spring 30, brings it out of its horizontal position shown in FIG. 3 into the tilted position shown in FIG. 4. By tilting the feed plate 27, the support rod 5 is clamped in the opening 28 at the edge and at the same time is pushed out of the projection 31 upward out of the telescopic tube 4 in accordance with the stroke of the feed plate 27 caused by the nose 32 of the power transmission block 15.

If the handle 16 is now released by the operator, the operator moves back into the non-actuated position shown in FIG. 3 due to the pressure force exerted by the compression spring 30 on the feed plate 27 and thus the nose 32. The telescopic rod 5 can thus be moved out of the telescopic tube 4 in stages by pumping movements in the sense of repeated pivoting of the handle 16 between the non-actuated position and the actuated position. The 13 locking plate 24 does not hinder this extension movement of the telescopic rod 5, since it is only effective in the direction of insertion.

The support rod 5 is pushed out until the desired length of the telescopic support 1 is reached. If, during this extension movement of the telescopic rod 5, a certain load limit is exceeded, the leaf spring 17, as shown in FIG. 5, bulges toward the handle 16, as a result of which the overload signaling bolt 20 is pushed through the handle opening 21. This overload signaling bolt 20 then presses on the palm of the user and signals to him that the telescopic support 1 is starting to be overloaded, so that the telescopic rod 5 ideally does not extend any further.

Should a user ignore this overload signaling nevertheless, it is designed such that the leaf spring 17 is plastically deformed in the event of extreme overload actuation with imminent risk of breakage and damage to the telescopic tube support 1 from a certain overload path such that the force transmission block 15 can no longer transmit force. An exchange of a then bent leaf spring 17 is possible at any time.

6 to 8 show alternative embodiments of handles with overload signaling devices. 6 shows a handle 36, in which an overload signaling bolt 38 is attached to a power transmission block 37, which, when a relative movement between the power transmission block 37 and the handle 36 occurs from the inside thereof, through an associated handle opening 39 after a spring travel threshold of a compression spring has been exceeded 40 exits.

In FIG. 7, an ergonomically designed handle 42 is formed, which has a handle opening 43, through which an 14 support block 44 arranged overload signaling bolt 45 after

Exceeding a spring travel threshold of a leg spring 46 emerges when overload begins.

8 shows a third alternative embodiment of an ergonomic handle 48 adapted to the fingers of one hand. A pressure sensor 49 acts here as overload protection, which emits an optical and / or acoustic signal after a certain threshold value of an indicator has been exceeded.

In addition to the overload-protected, manually operated extension drive, the telescopic support 1 has a further extension drive designed as a spring drive 51. For this purpose, as can be seen from FIGS. 1 and 2 in connection with FIGS. 9 and 10, a tension spring 52 is contained in the first upper telescopic tube part 2. This tension spring 52 is connected at the upper end to an upper region of the telescopic tube part 2 and closed at the lower end by means of a block part 53. Alternatively, a rubber band could also be used here instead of the tension spring 52.

As can be seen in particular from FIGS. 9 and 10, a lower end of the telescopic rod 54 comes into contact with the block part 53 during the insertion of the telescopic rod 5 with the locking plate 24 pivoted upward according to the arrow 55. As a result, the tension spring is brought into the position shown in FIG 10 drawn extended position.

In order to prevent the telescopic rod 5 from being fully extended, a pressure 56 is formed at its lower end 54. An anti-lock washer 57 is also arranged on the lower end of the telescopic rod 54 above the pressing 56 so that this pressure does not jam with the head part 6 during the maximum extension. This prevents wedging due to a large contact surface. 15 To lock the spring drive 51, a spring drive locking plate 60 is formed as an angle part in a lower region of the cutout 14 of the head part 6. This spring drive locking plate 60 has a first angle leg plate 61, which comprises an opening 62 through which the telescopic rod 5 is guided. Furthermore, the spring drive locking plate 60 has a second angle leg plate 63 which is oriented perpendicular to the first angle leg plate 61 and which, in the illustration in FIG. 3, bears against a section of a link surface 64 of the force transmission block 15 which is approximated to a straight line.

The spring drive lock plate 60 is spring-loaded by a compression spring 65. This compression spring 65 is supported on the one hand at a lower end of the cutout 14 and on the other hand on an underside of the first angle leg plate 61 around the opening 62. In the angular range 66 of the spring drive locking plate 60, a shaft 67 is also provided, which is mounted on the head part 6.

In the non-actuated position of the handle 16 shown in FIG. 3, the first angle leg plate 61 of the spring drive locking plate 60 is pivoted out of the horizontal by the interaction of the link surface 64, shaft 67 and compression spring 65. As a result, the telescopic rod 5 is clamped at the edge in the region of the opening 62 of the first angle leg plate 61 and thus prevents it from being pushed out of the telescopic tube 4 when the tension spring 52 is tensioned.

When the handle 16 is transferred to the actuation position shown in FIG. 4, the power transmission block 15 is pivoted, the second angle leg plate 63 already after a short actuation path of the handle 16 due to the transition of the section approximating a straight line into a circular arc section of the link surface 64 is pivoted that it is parallel to the extension direction of the telescopic rod 16 5 is aligned. Overall, the spring drive locking plate 60 is pivoted so against the pressure direction of the compression spring 65 about the shaft 67 that the first angle leg plate 61 is aligned perpendicular to the extension direction of the telescopic rod 5. The section of the link surface 64, which is designed as an arc, also ensures that the spring drive locking plate 60 is held in exactly this release position even when the handle is actuated further, as a result of which the telescopic rod 5 is no longer jammed in the spring drive locking plate 60 and can be pushed out of the telescopic tube 4.

By releasing the handle 16, the pressure force exerted by the compression spring 30 on the feed plate and thus the nose 32 is transferred back into the non-actuation position shown in FIG. 3. Simultaneously with this transfer of the handle 16 into its non-actuated position, the spring drive locking plate 60 is also transferred again along the link surface 64 into the clamping position of the telescopic rod 5 shown in FIG. 3.

As can be seen from FIGS. 1 and 2, a manually displaceable retraction plate 71 is arranged on an upper telescopic rod area 70, by means of which the telescopic rod 5 can be pushed back into the telescopic tube 4 when the locking plate 24 is raised. As shown in FIG. 11, this retraction plate 71 has an opening 72 which is adapted to the hexagonal shape of the telescopic rod 5. It is thereby achieved that the retraction plate clamps the upper telescopic rod region 70 at a position of the retraction plate which is oriented at an angle to the telescopic rod axis, as a result of which it can be inserted in a simple manner. A recess 73 is also formed on the retraction plate 71 as a hanging option for tools. This attachment option can be particularly helpful when working on an easel, for example by B. a drill can be hung. 17 In the pushed-together state of the telescopic support 1 shown in FIG. 1, in which the tension spring 52 of the spring drive 51 is tensioned, the entire system is held under a pretension. To prevent the telescopic rod 5 from being pushed out unexpectedly by e.g. B. to avoid improper handling or during transport, a pipe clip 75 shown in Fig. 12 is provided as an additional extension lock. This tubular linch pin 75 comprises a locking bolt 77, to which a foldable bracket 78 is articulated. As can be seen from FIG. 13, the locking bolt 77 is pushed into a locking opening 76 of the head part 6, whereby it fixes the second angle leg plate 63 of the spring drive locking plate 60 in the position shown in FIG. 3. The spring drive 51 is thus permanently blocked. So that the pipe flap plug 75 cannot be lost, it is attached to the head part 6 by means of a simple chain 79.

Claims

18 Claims

1. telescopic support,

Consisting of a telescopic rod telescoping in at least one telescopic tube and a manually operable feed means for gradually extending the telescopic rod from the telescopic tube, the feed means comprising a handle with a force transmission block pivotably mounted on the telescopic rod and the force transmission block transmitting force when the handle is actuated engages the drive of the feed means,

characterized,

that the handle (16; 36; 42; 48) is movably mounted on the power transmission block (15; 37; 44),

that the handle (16; 36; 42; 48) is coupled to the power transmission block (15; 37; 44) by at least one spring element (17; 40; 46), such that the spring element (17; 40; 46 ) is deflected with a travel corresponding to the size of the actuating force, and

that in the event of an inadmissible overload of the telescopic support (1) and / or the components used corresponding to an overload actuating force on the handle (16; 36; 42; 48) at least part of the spring element (17; 40; 46) has an assigned spring travel - 19 threshold to an overload spring travel is exceeded and thereby by the assigned relative position between a spring element part and the handle (16; 36; 42; 48) or the power transmission block (15; 37; 44) and / or by the assigned relative position between the power transmission block (15; 37; 44) and the handle (16;

36; 42; 48) overload signaling means (20; 38; 45) can be activated as overload protection.

2. Telescopic support according to claim 1, characterized in that the spring element (17; 40; 46) is plastically deformable in the event of extreme overload actuation before an imminent risk of breakage and damage from a certain overload spring travel, such that when the spring element (17; 40; 46) the connected power transmission block (15; 37; 44) cannot engage the drive in a power-transmitting manner.

3. Telescopic support according to claim 1 or claim 2, characterized in

that the spring element is a leaf spring (17) which extends from a free

Support the end (18) of the handle (16) starting from the power transmission block (15) and bulge in the direction of the inner surface of the handle when the handle is actuated, and

that an overload signaling bolt (20) is arranged in a central area of the leaf spring (17), which emerges from a handle opening (21) in the hand-rest area when the spring travel threshold is exceeded.

4. Telescopic support according to claim 1 or claim 2, characterized in 20 that an overload signaling bolt (38; 45) is attached to the power transmission block (37; 44) and, when there is a relative movement between the power transmission block (37; 44) and the handle (36; 42), from the inside thereof through an associated handle opening (39; 43) emerges after the travel threshold is exceeded, and

that the spring element is a leg spring (46), a compression spring (40) or a leaf spring.

5. Telescopic support according to claim 1 or claim 2, characterized in that sensor elements, preferably a limit switch, are arranged on the power transmission block and / or on the handle (48), which can be activated after the travel threshold has been exceeded and to which at least one acoustic and / or visual alarm transmitter connected.

6. Telescopic support according to one of claims 1 to 5, characterized in that the feed means is a ratchet arrangement, rack arrangement or clamping arrangement.

7. Telescopic support according to claim 6, characterized in

that the feed means comprises a manually operable locking plate (24) and a feed plate (27) each with an opening (21, 25) through which the telescopic rod (5) is guided,

that the locking plate (24) and the feed plate (27) on the telescopic tube (4) are pivotally held and spring-loaded in the direction of insertion, such that the unactuated locking plate (24) is pivoted into the locking position and the telescopic rod (5) is prevented from being pushed in locks and the feed plate (27) for the telescopic rod (5) freely Is 21, and

that as a drive on the feed plate (27) a nose (32) of the power transmission block (15) in the extension direction of the telescopic rod (5) can be brought into contact and the extension drive can be actuated in stages with pumping movements of the handle (16).

8. Telescopic support according to one of claims 1 to 7, characterized in

that the telescopic support (1) in addition to the overload-protected, manually operated extension drive comprises a further extension drive as a spring drive (51), with a tension spring (52) which is contained in the telescopic tube (4) and at the lower end preferably via a block part (53) with the lower telescopic rod end (54) can be connected in a detachable system and is connected at the upper end to an upper region of the telescopic tube (4), so that the tension spring (52) is pulled out and prestressed when the telescopic rod (5) is inserted, and

that in the upper area of the telescopic tube (4) a manually operated, spring-loaded spring drive locking plate (60) is arranged with a similar structure to the locking plate (24) and feed plate (27) and this spring drive locking plate (60) locks the spring drive (51) unactuated.

9. Telescopic support according to claim 8, characterized in that the spring drive locking plate (60) is designed as an angular part through the first approximately transverse to the extending angle leg plate (61), the telescopic rod (5) is guided and the second angle leg plate (63) on a link surface ( 64) of the power transmission block (15), such that when the handle (16) is open, the first

Angle leg plate (61) by the associated spring (65) in it 22 is in the tilted blocking position and after a short actuation path of the handle (16) is transferred to the release position, after which the link surface (64) forms a circular segment around the pivot axis of the power transmission block (15), so that with a further actuation path of the handle ( 16) the first angle leg plate (61) remains in the release position.

10. Telescopic support according to claim 9, characterized in that the first angle leg plate (61) and thus the spring drive locking plate (60) through a through at least one locking opening (76) in

Telescopic tube (4) insertable locking bolt (77), preferably as a pipe linch pin (75), cotter pin or spring pin can be fixed in its locked position.

11. Telescopic support according to one of claims 1 to 10, characterized _^ characterized in that on the telescopic rod (5) a hand-operated and hand-movable retraction plate (71) with a similar structure to the locking plate (24) is attached, the free end of which as a hanging device ( 73) is formed.

12. Telescopic support according to one of claims 1 to 11, characterized in that the telescopic rod (5) is polygonal in cross section, preferably designed as a hexagon.

13. Telescopic support according to one of claims 1 to 12, characterized in that the pivotable handle (16) with overload protection, the feed means and optionally the upper connection of the tension spring (52) and the spring-loaded spring drive locking plate (60) on a head part (6) of the Telescopic tube (4) are arranged, which is placed on the tube (4) or inserted into this.