Linear actuator with piston segments

Abstract

Linear actuator with piston segments, for lifting, lowering or moving loads, comprising: • a housing sealed to the environment, which has an opening with a laterally acting seal, wherein • this opening has a guide which guides the piston segments exiting it laterally, as well as • this opening can either be provided with a piston segment with a cover surface that is axially movable in the opening and seals against the housing, as well as • another opening in the housing to which the inlet of a pressure medium can be connected, e.g. coming from a hydraulic pump, as well as • Piston segments that fit slidably along their longitudinal axis into the aforementioned housing opening and that can be positively, detachably and tightly connected to each other, characterized in that • a piston segment, which is wholly or partially located outside the housing, moves with its body axis, which is parallel to the direction of movement of the working stroke, parallel or collinear to a line whose original position and / or orientation need not be parallel or collinear to the original position and / or orientation that the piston segment with the same body axis had during its initial position in the housing, wherein • the starting positions of the piston segments, which, unlike piston segment (38), do not have contact with the pressure of the environment of the housing, are on a movement path such as in Fig. 11, (B28) within the housing and these piston segments are not yet positively connected and / or tightly connected to another piston segment and • a mechanism is present which connects or separates the piston segments in a detachable, tight and form-fitting manner

Description

[0001] The present invention relates to a linear actuator with piston segments. This linear actuator is designed to lift or move loads and, in field applications such as rescue operations, to provide a handy device that offers a large, usable stroke relative to its weight and housing height. Further applications for this linear actuator include situations where a large lifting height is required for a limited time. For example, a flagpole that needs to be lowered back into the ground after use without having to drill a hole at least as long as the flagpole. The same applies to hydraulic elevator drives or vehicle lifts, which require ample space to accommodate the height of the working piston. Tools for drilling, for example,Utility shafts extending laterally from an access shaft, bollards limiting the flow of traffic, or a barrier which cannot be mounted in a rotatable manner due to space constraints. State of the art

[0002] Hydraulic cylinders are used, among other things, for lifting, lowering, or moving loads. These cylinders, available in single- or double-acting versions, come in various lengths and force capacities. Telescopic cylinders or cascades of cylinders are used to bridge larger distances. Since the piston must be enclosed within a cylinder throughout its range of motion, this range is directly linked to the length of the cylinder, and thus limited by it. This is particularly disadvantageous when the available distance between the cylinder's mounting surface and the target load height is greater than the cylinder height itself, but less than the height of a cylinder that would be practically suitable for this application. The choice of cylinder is often limited by factors such as its manageable weight and its lifting capacity.

[0003] Telescopic cylinders, e.g., patent number FR 00 0002 834 318 A1, do achieve a relatively large stroke height compared to the overall height of the telescope in its retracted state, but this comes with many disadvantages. These disadvantages include the decreasing lifting force segment by segment as the stroke increases, as well as the changing stroke speed due to the different volumes of the individual piston segments. Another disadvantage is the weight of such a telescopic cylinder.

[0004] Solutions also exist in the field of hydraulics where individual piston segments are joined together to achieve a specific target length. However, these solutions often have the disadvantage that the individual piston segments must be assembled before pressure can be applied to the piston. After use, these pistons must then be disassembled again. A similar solution can be found under patent number KR 20 2008 004 565 U or CN 00 0215 924 253 U. Other solutions using piston segments require a large number of parts and valves for operation. This makes their operation costly and prone to malfunctions.

[0005] The object of the invention is to develop a compact linear actuator that has a greater usable stroke height than the height of the housing plus the longest single piston segment located within the housing. This should be achieved with the lowest possible weight, no changes in piston exit velocity dependent on the stroke height, and no segment-by-segment changes in the stroke force.

[0006] This problem is solved according to the invention with a linear drive according to the features of claims 1 to 4. Further advantageous embodiments can be found in the dependent claims. Advantages of the invention

[0007] The invention relates to a linear actuator whose housing is sealed from the environment and can be pressurized by a hydraulic pump. Piston segments are located within the housing and can be detachably and tightly connected to one another via a mechanism within the housing, as well as separated from one another. The piston segments themselves are traversed by a universally movable tension member, which can be locked or unlocked relative to the piston segment via a mechanism located within the piston. As the pressure in the housing increases, the piston segments located at the housing opening are guided linearly outwards from the housing into the surrounding environment, thereby pulling pistons from the magazine within the housing via the connection of the universally movable tension member.This pulling motion activates the mechanisms in the piston segments and the housing, drawing the piston segments together before they exit the housing, creating a positive-locking, tight, and releasable connection. The more pressure builds up in the housing, the more piston segments are assembled and pushed outwards. When the pressure in the housing drops again, the assembled piston train retracts, the piston segments separate, and are pushed into the magazine. When lifting a load, i.e., when a force is applied perpendicular to the first piston, the pulling mechanism is subjected to frictional forces, sealing forces, and the force components caused by springs. The force caused by the pressure difference between the hydraulic fluid and the ambient pressure, which acts on the top surface of the first piston segment, contributes only the portion that acts as a reaction force due to the aforementioned forces such as friction, springs, etc. If the linear drive is also to transmit tensile forces, this is also possible with a mechanism installed in the corresponding piston segments.

[0008] In this way, a lifting mechanism is housed in a casing, which avoids the disadvantages of a telescopic cylinder, such as the load capacity changing with the lifting height, the segmentally changing lifting speed, or the space requirements and weight of a cascade arrangement of individual cylinders, or the unwieldy length of a simple cylinder.

[0009] Advantageously, the piston segments in the magazine area of ​​the housing are arranged so that they can be removed and reinserted using a simple mechanism consisting of springs and guides. The sections of the drive element located outside the piston segments are housed in corresponding guides and recesses in the housing to prevent them from obstructing the transport system of the magazine area.

[0010] In a further advantageous embodiment, mechanisms are housed within the piston segments that deflect and guide the tension member passing through them. These mechanisms also serve to prevent the tension member from passing through the piston segment housing, i.e., to lock it, when a force from outside the piston segment acts on a locking mechanism of the mechanism. This prevents the tension member from moving further away from the piston segment preceding it in the sequence of piston segments, but it does not prevent the piston segment from approaching the piston segment in front of it, thus shortening the section of the tension member between it and the piston segment ahead. This is advantageous when the piston segments are connected to one another.

[0011] Further development of the locking element in the mechanisms can have additional advantageous functions, such as a temporary release of the lock, which allows the piston segment to travel a certain distance to the piston segment in the sequence in front of it without being prevented from doing so by the pulling element and the lock.

[0012] The aforementioned function of the locking mechanism in the piston segment mechanism can be advantageously utilized by employing a spring element which, after the locking mechanism is released, pushes a connected piston segment away from itself. When the locking mechanism re-engages, a gap is created between this piston segment and the one it pushed away.

[0013] This distance between two piston segments advantageously allows access to a piston segment from outside the piston segments in order to access the functions of the mechanics located there.

[0014] In an advantageous embodiment, the piston segments have a contour that allows a detachable, positive-locking connection to each other and also have a seal that seals the piston segments to each other.

[0015] In a further embodiment of the invention, the piston segments are provided with a geometry which connects the piston segments to each other in a detachable manner so that the piston segments can transmit a torque.

[0016] This torque can serve, for example, as a carrier for a rotary tool such as a drill bit in a further advantageous embodiment of the invention.

[0017] Alternatively, the torque can be transferred into the housing of the linear actuator if the cross-section of the housing opening, as well as the cross-section of the piston segments, is not round.

[0018] In a further advantageous embodiment, the piston segments can have an integrated device that locks the piston segments relative to each other in their longitudinal axis direction, thus enabling the transmission of tensile forces to the piston segments. This lock can be released via the mechanism integrated into the piston segments. Drawings

[0019] Further details of the invention are described in the drawing with reference to schematic embodiments, where it shows Fig. 1 an isometric representation of the linear drive, Fig. Figure 2 shows a top view of the linear drive, as well as the location of sections BB and CC. Fig. Figure 3 shows, with section BB, an overview of the main level of the mechanics for the assembly and disassembly of the piston segments. Fig. Figure 4 shows an overview of the main level of the safety valve with section CC. Fig. Figure 5 shows, with detail D, the operation of the safety valve in the open position. Fig. Figure 6 shows, with detail E, the operation of the safety valve in the closed position. Fig. Figure 7 shows, with detail F, the operation of the safety valve in the closed position in conjunction with the last piston segment. Fig. Figure 8 shows an exploded view of the linear drive. Fig. Figure 9 shows an exploded view of the system carrier and its components with detail K. Fig. 8, Fig. Figure 10 shows a top view of the housing without the housing top part (5) with a view of the magazine area in which the piston segments are mounted, as well as an opening with a view of the piston segment which is currently resting against spring element (4), Fig. Figure 11 shows a functional diagram of the spring forces of the magazine area. Fig. Figure 12 shows an exploded view of a piston segment and its mechanics. Fig. Figure 13 shows the top view of a piston segment as well as the position of sections HH, 1-1 and GG, Fig. Figure 14 shows, with section CC through a piston segment, the plane in which the traction element (29) is guided, Fig. Figure 15 shows, with section 1-1 through a piston segment, the plane in which the mechanism in the piston segment with the lock in the open position is shown. Fig. Figure 16 shows, with section HH through a piston segment, the plane in which the mechanism in the piston segment with the lock in the closed position is shown. Fig. Figure 17 shows the open lock with detail J, Fig. Figure 18 shows the closed lock with detail L. Fig. Figure 19 shows a further embodiment of the invention with a functional diagram, Fig. Figure 20 shows a piston segment with a snap lock as a further alternative design option, Fig. Figure 21 shows a functional diagram with the course of the traction element (29) through the piston segments, Fig. Figure 22 shows in detail, with section BB, the function of the control lever (16) and the control element (25), Fig. 23 shows a variation of section BB, the difference being the reference to the representation on Fig. 2 is the changed position of the piston segments (19), the control lever (16), Fig. Figure 24 shows a further, advantageous embodiment of the invention with a direct drive of the linear drive by motor, Fig. Figure 25 shows a further advantageous embodiment of the invention with a manually operated hydraulic drive. Description of the exemplary implementations

[0020] The in Fig. Figure 1 shows the two housing halves (5) and (1), as well as the port (B3) for connecting a hydraulic pump. The piston outlet (B51) with the first piston segment (36) and one of the intermediate piston segments (19), which together form the piston assembly (B52), can be seen on the top side. The reset button (B22) and the flange (B4), which connects the two housing halves, are also shown.

[0021] In Fig. 2 are in the viewing direction A from Fig. 1, i.e., the top view of the housing top part (5) shows the two section lines BB and CC.

[0022] Fig. Figure 3 shows section BB, which depicts the assembly / disassembly plane. Protruding from the upper housing part (5), the piston segments (36) and (19) are visible as a combined piston assembly (B52). The positive-locking connection of the two piston segments is shown in area (B8), which is sealed against the environment by the piston seal (20) and the housing-side seals (6). Area (B6) directly below these piston segments shows the control lever (16), which is guided in the system carrier (13) and held in a starting position by the double-lever spring (17), or returned to it when the control lever (16) is deflected. (B20) indicates the path of a universally movable tension member. Due to CAD limitations and for clarity, this tension member is partially represented as a thick dashed line in this and subsequent figures.This tension element runs through all piston segments over the deflection rollers (22) located in the piston segments. Seal (7) seals the two housing halves, (5) and (1), against the environment. (2) shows the two seals that seal the system carrier (13) in the area of ​​the screw passages of the screws (44) from the upper housing part through the system carrier (13) into the lower housing part (1) to the environment of the housing. The screws (44) serve to stabilize and stiffen the housing consisting of (5) and (1) against the pressure of the pressure medium. The spring element (4), which is attached to the lower housing part by the screws (41), holds the piston segments in the magazine area of ​​the lower housing part (1) against the force of the spring element (15), which acts on the slide (14) on all piston segments in the magazine and pushes them towards the spring (4). Area (B9) shows the guide head of slide (14) with the surfaces (B10).These surfaces (B10) are the contact surfaces between the slide (14) and the system carrier (13). The slide moves through the magazine over these contact surfaces, pushing the piston segments ahead of it. (B7) shows a recess in the lower part of the housing (1), which serves to accommodate the tensioning element (29) and thus allows the piston segments to rest flat and move freely through the magazine.

[0023] The control element (25) in the piston segments has three functions, depending on its current position in the piston segment. A) The control element (25) releases the locking of the position of that piston segment with which the aforementioned piston segment is positively connected. B) The control element (25) holds the position of two interconnected piston segments relative to each other via the universally movable tension element (29). C) The control element (25) fixes the length of the universally movable pull element (29) between two piston segments when these are not connected to each other.

[0024] Fig. Figure 4 shows section CC, which depicts the main plane of the safety valve (8). (B1) marks the interior of the housing as a sealed space, the differential pressure of which affects the surfaces of all unmounted piston segments in the housing, as well as the inner surfaces of the piston segments protruding from the housing and sealed to the environment by the seals (6) and the piston seals (20) inserted on the piston segments. The spring (4) is in contact with another piston segment (19), which is located between the piston guide (B16) and the magazine. The safety valve (8) is designed to stop the operation of the linear actuator when either the last piston from the magazine contacts the piston guide (B16), and / or when a condition arises in which piston segments (19) are forced out of the housing without a sealed connection to the environment with the housing (5) and with each other.This is shown in more detail in the following detailed views (D), (E) and (F).

[0025] Fig. Figure 5 shows Detail D with the safety valve (8) in the open position. Area (B14) shows the open point where the seal (12) allows the flow of the pressure medium from the hydraulic pump. This pressure medium flows through the inlet port (B3) and through the openings (B11) into the housing of the linear actuator. The force of the spring (10), together with the force from the differential pressure of the ambient air and the pressure medium acting on surface (B12), pushes the safety valve (8) upwards, i.e., in the closing direction of the valve. The release mechanism (11), which contacts the safety valve (8) via the cone in area (B23), counteracts these forces. Simultaneously, the release mechanism (11) contacts the piston segment (19), which, through contact at point (B13), prevents the valve from closing. The spring (3) is designed so that its force acts in both directions of movement of the trigger (11).This allows the force to act both in the direction of the piston guide (B16) and in the opposite direction. This ensures that the cone in the area (B23) of the safety valve (8), even when the linear actuator is depressurized, remains in constant contact with the release mechanism (11) due to the forces of the two springs (3) and (10). The seal (9) seals the safety valve (8) against the environment via the housing.

[0026] Fig. Figure 6 shows detail E, which differs from section CC in Fig. Figure 4, to which this detail refers, shows the safety valve (8) in a closed position. The closed position of the safety valve (8) is visible from outside the housing with its parts (5) and (1) at the protruding position (B15) of the reset button (B22). The area (B18) shows how the seal (12) has closed the flow cross-section of the pressure medium coming from the hydraulic pump. This is because there is no piston segment in the piston guide (B16) blocking the area (B17), and the trigger (11) is thus pushed into the area (B16) of the piston guide by the spring force of the spring (3). The safety valve (8) is pushed upwards by the force of the spring (10) until it is stopped by contact with the trigger (11) in the area of ​​the cone on the safety valve (8).No more pressure fluid can flow from the hydraulic pump through the inlet port (B3), and further extension of the piston assembly from the housing is stopped. To lower the load, the hydraulic pump must first be switched off so that the safety valve (8) is relieved of the pressure of the pressure fluid. Then the user can press the reset button (B22). The piston assembly then pushes the release mechanism (11) back into place as it retracts.

[0027] Fig. Detail 7 shows Detail F, which differs from section CC in Fig. Figure 4, to which this detail refers, shows the safety valve (8) in a closed position and the last piston in the magazine (35) resting in the piston guide. The fact that the safety valve is closed is evident from the raised area (B15) of the safety valve (8). Area (B19) shows the special feature of the last piston segment, which differs in its shell geometry from all other piston segments. There is a groove near the lower end of the piston segment into which the trigger (11) is pushed by the spring (3), whereupon, as described in section

[0047] , the supply of pressure medium is blocked.

[0028] Fig. Figure 8 shows an exploded view of the linear actuator, revealing the individual components. Section (K) is then shown as a detailed view, illustrating the mechanical structure and assembly / disassembly mechanism. Section (B21) shows the piston segments housed in the magazine within the lower housing (1). The illustration of the lower housing also reveals the spiral magazine, which in practice may have more turns than shown in this example to accommodate a greater number of piston segments. The names of the individual reference numerals can be found in the accompanying reference numeral list.

[0029] Fig. Figure 9 shows the detailed view K of the exploded view of Fig. 8. The structure of the system carrier (13) is visible here. Its purpose is to house the mechanism for assembling and disassembling the piston links, as well as to divide the interior of the housing so that the piston segments remain in place in the magazine area. The outer edge contour (B10), which has a scaled-down version of the magazine's spiral shape, provides a guide surface for the slide (14), visible in Fig. 8, which guides the slide through the magazine. The system carrier (13) also accommodates the safety valve (8) with its mechanism, consisting of components (3), (9), (10), (11) and (12). The slots (B11) for guiding the hydraulic or pneumatic pressure medium, as described in section

[0048] , and the contact cone area (B23) are also visible here. The seal (2), described in section

[0046] , is shown here with the insertion groove and the through-holes for the screws that enclose this seal and thus seal it against the environment of the linear actuator. (B25) shows the receptacle for the spring element (15), which is positively inserted here. The double-legged torsion spring (17) is inserted into the control lever (16) and into the system carrier (13) and is held in place by the cylindrical pin (57).The two spring coils of the double-lever spring (17) allow the control lever (16) such a large angle of rotation that, guided by the cylindrical pins (46) and (57) in the grooves (B5) and the lateral guide surfaces (B26), it can completely clear the path for the piston segments moving up or down in the guide area (B16). When the control lever (16) is not subjected to force by a piston segment, it is returned to its starting position by the double-lever spring (17), where it is held by the spring-loaded pressure pieces (18) on the recesses (B24) until the next contact with a piston segment. The system carrier (13) is connected in addition to the through-bolt connections (46), as shown in [reference missing]. Fig. 8 are screwed to the lower housing part (1) by the screws (44). This ensures easy assembly of the linear drive, as well as additional stiffening.

[0030] Fig. 10 shows a view analogous to Fig. 2, View A, but without the upper housing part (5). The view shows the assembly of the system carrier (13) with its components, as well as the view of the spiral magazine with the piston segments. The fully movable pull rod (29) emerging from the piston segments in the magazine area is also visible here. Starting from the inside of the first piston segment (38) and extending to the underside of the slide (14), it runs from the top of one piston segment to the underside of the next. Area (B10) shows the guide area of ​​the slide (14) located above the piston. The upwardly inclined segment piston (19) can be seen through an opening.The spring element (15), which acts on the slide (14), can be designed such that, from its initial position (i.e., all piston segments are in the magazine) to its final position (i.e., all piston segments are out of the magazine), it exerts a force on the slide (14) to push the piston segments out of the magazine and, when the piston segments retract, to pull them back into the magazine. The designations of the other reference symbols in this view can be found in the reference symbol list in the appendix.

[0031] Fig. Figure 11 shows a functional diagram of the spring forces of springs (4) and (15) acting on the magazine contents (B21), which are moved along the guide surfaces of the magazine (B28), shown here as a line. The interaction of these two forces, in conjunction with the movement of the piston segments caused by the pressure difference between the pressure medium inside the housing and the surrounding environment, results in the removal of the contents from the magazine and, conversely, the return of the piston segments to the magazine. The function of spring (4) is to guide the piston segments to or from the piston outlet (B51), while simultaneously preventing further piston segments from sliding out of the magazine.Both spring forces A and B hold the magazine contents together, but at the same time also ensure the orderly process of removing piston segments from the magazine area or filling the magazine area with piston segments, which is required in the operation of the linear drive.

[0032] Fig. Figure 12 shows an exploded view of the mechanics of a piston segment (19). The piston segment (19) itself has a groove for receiving the seal (20). This groove is located on a shoulder on the piston's upper surface, the diameter of which fits snugly into the underside of the next piston segment. This creates both a tight and stable connection that can withstand lateral forces. Inside the piston are the two piston inserts (21) and (30), which are mirror images of each other. These are aligned with each other via the cylindrical pins (31) in the bores (B32) and rotatably connected to the piston segment (19) by the screws (32). The fact that the piston inserts are mounted in the piston segments is important because of the omnidirectionally movable tension member (29), in order to minimize any torque that may arise during operation from the piston segment (19) on the sections of the tension member (29) extending from and into the piston inserts.The recesses (B31) provided in the piston inserts (21) and (30) serve to guide the tension member (29). The recesses (B33) accommodate the deflection drums (22), which are shaped such that their outer surface has a form that positively guides the universally movable tension member (29) and, through this shape, can also absorb a torque from the movable tension member (29). The end face of the deflection drum (22) has a profile that fits into the end face profile of the locking discs (23), thereby allowing rotation of the deflection drum (22) in one direction but blocking the opposite direction of rotation. The resulting torque is directed into the two bolts with transverse bores (24), which are rotatably mounted in the two piston inserts (21) and (30) and can be moved laterally, i.e. towards or away from the deflecting drum (22), by the two guide rods (27), at one end of which the ball heads (28) are attached.This causes the control element (25), to which the two guide rods (27) are rotatably attached by cylindrical pins (33), to press the locking discs (23) against the upper deflection drum (22) against the force of the springs (34), thereby locking the drum in one direction of rotation. The recess (B30) provides access for demolding the piston inserts in injection molding processes or for access for the milling cutter in machining processes in the piston inserts (21) and (30) of the guide channels for the ball heads (28). The spring (26) is designed to have the force to repel a piston segment located beneath it against opposing forces to such an extent that a distance is created between the piston segments sufficient to allow the control lever (16) to engage the control element (25).Following this engagement, its locking elements (23) are briefly moved away from the deflecting drum (22) and unlocked. During the time the deflecting drum can rotate freely, the section of the tension member (29) located between the repelled and repelling piston segments can move through the repelled piston segment until the two springs (34) press the locking discs (23) back against the deflecting drum (22), thus locking it in one direction of rotation. The time it takes for this process determines the length of the section of the tension member (29) between two successive piston segments that are not sealed and positively connected. Alternatively or additionally, this length can also be defined by spacers inserted into the tension member (29).

[0033] Fig. Figure 13 shows the top view of a piston segment, showing the position of sections HH and 1-1, which pass through the control mechanism in the piston segments, and the position of section GG, which passes through the guide plane for the universally movable tension element (29).

[0034] Fig. Figure 14 shows section GG, which illustrates another advantageous design possibility for the piston segments. For example, a structure capable of transmitting torque can be incorporated at (B50) or other suitable locations. In this case, one piston segment has this structure on its upper surface, which in turn fits positively into another structure incorporated into the underside of a further piston segment. In this way, the piston assembly, located outside the housing, can transmit torque to the housing of the linear actuator. For example, when the piston outlet (B51) is in Fig. 1 of the housing upper part (5) is not circular in shape and the cross-section of the piston segments is designed analogously to its shape.

[0035] Another advantageous embodiment of the invention for the purpose of transmitting a torque is the application of the possibility of the structure of (B50) described in the preceding section

[0057] in Fig. 14, wherein the piston train outside the housing is not prevented from rotating by the piston outlet (B51), but, for example, a motor drive moves the piston train outside the housing (B52) Fig. 1. Set in rotation. In this way, the piston train can simultaneously exert a pressure or tensile force and a rotational force on a tool, e.g. drill rod, without requiring an interruption of the tool's feed to adjust the length of the rod carrying the tool (e.g., a drill bit).

[0036] Fig. Figure 15 shows section 1-1, which shows the mechanism for locking the universally movable traction element (29) in the locked position.

[0037] Fig. Figure 16 shows section HH, which shows the mechanism for locking the universally movable traction element (29) in the open position.

[0038] Fig. Figure 17 shows detail J, with the locking mechanism of the deflection drum (22) open, as visible in section (B34). Section (B36) shows the path of the guide for the ball heads (28). This guide has a raised section, with a dip before and after it. This means that the ball head (28) guides the locking disc (23) to the deflection drum (22) via the bolt with transverse bore (24) in the sequence locked, open, locked. This is necessary for the assembly of the piston segments (19), (37), and (35). Before one piston segment is mounted to another, the control element (25) must be in its initial position (P1). This position (P1) limits the possible directions of rotation of the deflection drum (22) in the direction in which the piston segment to be mounted is to be pulled towards its mounting partner, i.e., the other piston segment, with the universally movable pulling element (29).When the piston segment arrives at its destination, it initiates the movement of the control element of this piston segment during the formation of the positive-locking and tight connection with this assembly partner. During the assembly process, the ball head (28) changes position from (P1), through (P2), to (P3). Thus, the two piston segments are connected to each other via the positive-locking connection of their shape and via the now locked section of the universally movable tension member (29) between the two segments.

[0039] Fig. Figure 18 shows detail L, with the locking mechanism of the deflection drum (22) closed, as visible in area (B35). The ball heads (28) have thus reached the end point (P3) of the guide (B36).

[0040] Fig. Figure 19 shows a further advantageous embodiment of the invention with a functional diagram of an assembly of actuators (B42), (B43), (B44), and sensors (B48), (B49), which are jointly controlled by the controller (B46). In this assembly, the rod (B41), which here represents the piston assembly, protrudes from the housing (B41), which, in a simplified, schematic way, represents the upper housing part (5) in the aforementioned sections. This rod (B41) is held alternately by the clamping devices (B43), after which the clamping device (B42) opens. The pusher device (B44) then pushes the piston rod a short distance into the housing (B47). As soon as the sensor (B49) receives a signal, the pusher device (B44) stops, and the clamping device (B42) again holds the piston assembly (B41) securely.The clamping devices (B43) then release the piston assembly, and the pusher device (B44) returns the clamping device to its initial position, which is detected by sensor (B48), whereupon the cycle restarts. Using this functional scheme, which is known in the art, the system of separate piston segments underlying this invention can also be retracted hydraulically or pneumatically and can thus transmit large tensile forces. Rods driven in this way, but without the segmented piston technology underlying this invention, are prior art.

[0041] To prevent the universally movable tensioning element (29) from having to withstand large tensile forces when the piston segments are retracted under tension, the mechanism described in sections (19) to (26) can be supplemented in the piston segments (19), (37) and (35) by a further advantageous function. This function is described in Fig. Figure 20 shows the locking latches (58). These locking latches are engaged in the groove (B39) of the assembly partners during the assembly of the piston segments, with the chamfer (B40) eliminating the need to retract the locking latch during the assembly process of the piston segments relative to each other. Coupled with the mechanics of the piston segments, these locking latches are retracted during disassembly.

[0042] In Fig. Figure 21 illustrates the assembly of the piston segments (19), (37), and (35) in a functional diagram. In this diagram, the universally movable tension member (29) extends through the piston segments and is attached at one end to the first piston segment (37) and at the other end to the slide (14). When a section of the universally movable tension member (29) is pulled—referred to as the tension member in the functional diagram—the length of the tension member (29) between the upper deflection pulley of the lower piston segment—in this example, piston segment (35), i.e., the last piston—and the piston segment above it, in this example, piston segment n+1 (19), decreases. When the string of assembled pistons exits the housing during operation of the linear actuator, this string pulls the tension member (29) with it.If the speed of the piston segment located directly below this already assembled string of piston segments is decelerated, its internal, locked mechanism will pull on the described section of the tensioning element (29), whereupon the distance between the lower piston segment and the preceding piston segment decreases until the two piston segments are positively engaged. This process continues as the piston segments extend until the last piston (35) is stopped by the mechanism of the safety valve (8), as described in section

[0050] . Fig. 7 explained. The end of the traction element (29) is pushed forward by the slide (14), so that there is no build-up of the traction element (29).

[0043] As an alternative to the configuration of the universally movable pulling element described in section

[0065] and its design with a beginning and an end, this element can also be modified and used in other variations as a further advantageous application. For example, with appropriate guidance by the piston segments, an endless, universally movable pulling element can also be used, which, similar to a Venetian blind, can be pulled at two points, with the piston segments contracting when pulled at one point and releasing from each other when pulled at the other. As a further advantageous embodiment of the use of this pulling element, it is also possible to divide the pulling element into individual, unconnected sections, with the ends of these sections being moved by the respective mechanisms in the piston segments and secured against slippage.

[0044] In Fig. Section BB, shown in Figure 22, illustrates how the control lever (16) comes into contact with the control element (25) of a retracting piston segment (19). This control element (25) is pressed into the piston segment (19) and, for the duration of the force exerted by the control lever (16) on the control element (25), releases the locking mechanism of the section of the universally movable tension member (29) between the piston releasing the locking mechanism and the piston segment above it, to which it is tightly and positively connected. The spring (26) in the piston above, which is not shown in this illustration, then ejects the piston segment below it. This is the disassembly process.

[0045] In Fig. Figure 23 shows in section BB how the deceleration of a piston segment (19) for the purpose of assembly with the preceding piston segment occurs by means of the control lever (16), as explained in section

[0065] . The lower piston segment (19) is decelerated as it moves upwards by the control lever (16) and the force of the double-legged torsion spring (17) connected to it, while the piston assembly above it moves faster. This draws the piston segment (19) positively into contact with the piston segment above it, with the control lever following this movement until, guided by the guide grooves (B5), it has completely disappeared from the area of ​​the piston guide (B16). As soon as the newly assembled segment piston (19) has moved upwards out of the detection range of the control lever (16), the lever pivots back to its initial position, which is held in place by spring-loaded pressure pieces (18) (not shown in this figure, see exploded view). Fig. The stop is at rest area 9 (B24). This is the assembly process.

[0046] Fig. Figure 24 shows a further advantageous embodiment of the invention with a motor drive. In this embodiment, the stroke movement of the piston assembly (B52) is not achieved via a pressure medium directed into the housing, but rather a motor (47) drives the piston assembly (B52) either directly or indirectly, e.g., as in the [reference to figure]. Fig. The solution shown in Section 24 uses gears (55) and (56) and a worm gear (48) which engages in a groove structure (60) in the piston segments. In this way, the mechanism described in the preceding sections can be used without seals, and when using the piston with locking function (59) described in Section (28), the invention can also be used with lifting and pulling functions. Motor-driven rods, but without the segmented piston technology underlying this invention, are prior art.

[0047] Fig. Figure 25 shows a further advantageous embodiment of the invention, in which a hydraulic pump (51) is actuated via the hand lever (50) and the pressure medium is conveyed via a line connection (52) into the housing interior of (5) and (1). In this way, the piston assembly (B52) extends and can be lowered again via a separate hand valve (not shown). Hydraulic drives of pistons with a hand pump are prior art, but without the segmented piston technology underlying this invention.

[0048] The invention, as described above, solves the problem of the dependence of the usable stroke height on the housing height in piston-supported actuators / lifting devices by ensuring that the piston segments, which share a direction of movement and a collinear axis of movement during extension and retraction, no longer need to be collinear with this axis in their resting state. Furthermore, the disadvantages known from telescopic cylinders, namely the changing lifting force with the stroke height and the segment-by-segment change in extension speed, are eliminated. Another significant advantage is the compact dimensions of the housing.

[0049] These and further developments of the invention are evident not only from the claims but also from the description and the drawings, whereby the individual features can be implemented individually or in combination with other features in the execution of the invention and can represent advantageous embodiments that are eligible for protection on their own. Reference symbol list 1 Lower case half 2 Seals Intermediate Covers 3 Spring element for trigger 4 spring element 5 Upper case half 6 Seal housing to piston 7. Seal between upper and lower housing parts 8 safety valve 9 Upper seal safety valve 10 compression springs for safety valves 11 triggers 12 Lower seal safety valve 13 system carriers 14 sliders 15 spring element 16 control levers 17 Double leg spring 18 Spring-loaded plunger 19 segmented pistons (each piston between the first and the last piston) 20 Seal Segment piston 21 Piston insert #2 for segmented pistons 22 Deflection drum 23 Locking disc 24 bolts with cross bore 25 Control element 26 Compression spring piston 27 Guide rod 28 ball head 29 Universally movable traction element 30 Piston insert #1 for segmented pistons 31 Cylinder pin 32 screw 33 Cylinder pin 34 Spring element 35 Last piston 36 spring element 37 First piston 38 Piston insert #1 for initial piston 39 Piston insert #2 for initial piston 40 screws 41 screw 42 screw 43 screw 44 screw 45 screw 46 Cylinder pin 47 Engine 48 snail 49 Spring element 50 pump levers 51 Pump 52 hose 53 Spring for trigger 54 screw 55 gear 56 gear 57 Cylinder pin 58 Lock Trap 59 pistons with locking function 60 pistons with transverse grooves B1 Sealed volume B2 Magazine B3 Inlet nozzle B4 Sealed flange of the housing B5 Guide grooves for control lever B6 Control lever in position separate piston B7 Shaft for pulley B8 First and second pistons installed B9 slider with spring and guide B10 guide surface slider B11 Slots for the pressure medium in the safety valve B12 Level Valve open B13 Level Trigger Retracted B14 Open sealing area B15 Valve closed B16 Piston guide B17 trigger extended B18 Closed sealing area B19 trigger on last piston B20 Course of the traction element B21 Magazine Contents B22 Reset button B23 Contact cone valve for trigger B24 Detent point for starting position control lever B25 Mounting point for spring element on the system carrier B26 Mounting surfaces Control lever to system carrier B27 screw dome housing flange B28 Guide surfaces of the magazine B29 Receptacle for locking washer B30 Manufacturing-related access for milling cutters B31 Guide for running traction element B32 Receptacle cylindrical pin for fixing the piston inserts B33 Mounting Deflection drum B34 Lock Deflection Drum Open B35 Lock Deflection Drum Closed B36 ball guide B37 windings double leg spring B38 Separation between magazine and piston exit axis B39 Nut (piston with lock latch) B40 chamfer on lock latch B41 Pistons mounted outside the housing B42 clamping device B43 clamping device B44 Push device B45 pump B46 control unit B47 Housing B48 Sensor B49 Sensor B50 position for gearing (torque transmission) B51 stabilizing struts B51 Piston outlet B52 piston train P1 Starting position Locking disc closed P2 Locking disc open P3 Position Locking disc closed

Claims

Linear actuator with piston segments for lifting, lowering, or moving loads, comprising: • a housing sealed to the environment, which has an opening with a laterally acting seal, wherein • this opening has a guide which guides the piston segments exiting it laterally, and • this opening can either be provided with a piston segment with a cover surface that is axially movable in the opening and seals against the housing, and • a further opening in the housing to which the inlet of a pressure medium can be connected, e.g.coming from a hydraulic pump, as well as piston segments that fit slidably along their longitudinal axis into the aforementioned housing opening and that are positively, detachably and tightly connectable to one another, characterized in that a piston segment which is wholly or partially located outside the housing moves with its body axis, which is parallel to the direction of movement of the working stroke, parallel or collinear to a line whose origin position and / or orientation need not be parallel or collinear to the origin position and / or orientation that the piston segment with the same body axis had during its initial position in the housing, wherein the initial positions of the piston segments, which do not have contact with the pressure of the environment of the housing like the piston segment (38), are on a path of movement as e.g. in Fig.11 , (B28) within the housing and these piston segments are not yet positively connected and / or tightly connected to another piston segment and • a mechanism is present which connects or separates the piston segments detachably, tightly and positively. Linear drive with piston segments according to claim 2, characterized in that a magazine area for the piston segments is provided, in the interior of which piston segments are located which are not positively and tightly connected to one another and on whose outer, top, or bottom surfaces the pressure medium cannot exert a force caused by a pressure difference, and the magazine can be flooded with a pressure medium so that the piston segments located therein are surrounded by the pressure medium on their top, bottom, and outer surfaces, and before the assembly process or after the disassembly process, the path of movement of the piston segments need not be entirely linear or circular, either as a combination or as a whole, but can, for example, have a different path as in Fig. 11, (B28). Linear drive with piston segments according to claim 3, characterized in that: • the piston segments are traversed by a flexible, elongated body, for example (29) in Fig. 21, which in turn can consist of movably connected elements or of a single, flexible body, wherein: • the flexible, elongated body has no end, i.e., can form a ring; or • the flexible, elongated body has an end and a beginning; or • the flexible, elongated body can consist of sections not connected to each other; and • the flexible, elongated body can have individual bodies that are part of its structure or that have been additionally attached to it in order to limit the distance between piston segments not connected to each other. Linear drive with piston segments according to claim 4, characterized in that: • a mechanism retrieves the piston segments from the magazine area before they exit the housing, e.g., Fig. 3, parts (14), (15), (4), and connects them to each other in a form-fitting, detachable and tight manner, e.g., Fig. 3, parts (19), (16), (17), as well as Fig. 12 and Fig. 14; and • this mechanism separates these piston segments from each other after they have returned to the housing and brings them into the magazine area. Linear drive with piston segments according to claim 5, characterized in that: • a mechanism as in example Fig. 12, parts (21) to (34) is located in the piston segments for the purpose of controlling the releasable connection to another piston segment and of detaching from another piston segment, which can be rotatably mounted about the longitudinal axis of the piston segment surrounding this mechanism, e.g. (19); and • this mechanism is secured in the piston segment against displacement parallel to the longitudinal axis of the piston segment, e.g., as with the screws (32) in Fig. 12; and • this mechanism has an element, e.g. (25), which controls it; and • the element (25) has a further element located outside the piston segment, e.g.,(16) or another piston segment which changes the position of this element (25) can be controlled in such a way that the assembly or disassembly process of the piston segments is initiated depending on the direction of movement of the piston segments, or the piston segments can have a locking mechanism which can be released by the mechanics in the piston segments to transmit a high tensile force, as shown, for example, in Fig. 20, which absorbs the tensile forces on the piston segments. Linear drive with piston segments according to claim 6, characterized in that: • a device is provided which stops the extension of the piston segments from the housing when a sufficient lateral guide length of the piston segments is undershot, and • the interruption of the operation of the linear drive caused by the device is lifted when the piston segments are retracted or when the device is manually reset, and • this device stops the supply of pressure medium when the pressure medium in the housing of the linear drive exceeds a fixed or adjustable pressure. Linear drive with piston segments according to claim 7, characterized in that: • the piston segments have a geometry, e.g., a toothing, which prevents rotation of the piston segments relative to each other and allows the transmission of a torque to the interconnected piston segments, e.g., Fig. 14, (B50), and • the cross-section of the opening in the housing of the linear drive, as well as the cross-section of the piston segments, is circular, or • the cross-section of the opening in the housing of the linear drive, as well as the cross-section of the piston segments, is not circular, and • the piston segments have a geometry, e.g., a toothing, which prevents rotation of the piston segments relative to each other and allows the transmission of a torque to the interconnected piston segments, e.g., Fig. 14, (B50). Linear drive with piston segments according to one of the preceding claims characterized in that: • The piston segments have a toothing on their outer surface, as an example Fig. 24 , (60), which are set in motion via mechanical intermediate elements, e.g. (48), (55), (56) via a motor (47) and thus do not require a supply of a pressure medium. Linear drive with piston segments according to one of the preceding claims characterized in that: • The piston segments are extended via a manually operated hydraulic system, as exemplified in Fig. 20 with the hand lever (50), and • The piston segments can be lowered again via a valve arranged separately or connected to a specific position of the hand lever (50). Linear actuator with piston segments according to one of the preceding claims, characterized in that: • The linear actuator, as exemplified in Fig. 19, has a structure with sensors (B48), (B49), a control (B46) electronic or via valves, and actuators (B42) to (B44) which hydraulically, electrically or pneumatically hold the detachably connected piston segments and push them into or pull them out of the housing.

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