Abstract:
A switchable device for supplying at least one consumer of an internal combustion engine with pressure. The device includes the following: a housing having a housing interior; a displacement element arranged in the housing, which element can be displaced between a first end position and a second end position, the displacement element having a pressure surface which at least partially delimits a fluidically connectible accumulator chamber together with the wall of the housing interior, the accumulator chamber being connectible to a pressure source in a fluid-conducting manner; an energy accumulator which interacts with the displacement element, the displacement element being displaceable against the force of the energy accumulator from the first end position into the second end position under the effect of pressure applied to the accumulator chamber; a locking mechanism by which the displacement element can be locked in the second end position; a switching mechanism which can be actuated by an actuator, has a switch element that can be brought into at least two switching positions and interacts with the locking mechanism in such a manner that the displacement element can be locked and unlocked in a first switching position of the switch element and cannot be locked and not unlocked in a second switching position of the switch element.

Description:
FIELD OF THE INVENTION 
     The invention lies in the technical field of internal combustion engines and relates to a switchable device for supplying pressure to at least one load of an internal combustion engine. 
     BACKGROUND 
     From Patent No. EP 1197641 A2, a pressure accumulator for supporting a hydraulically adjustable camshaft is known in which a flow of pressurized medium into or out of the pressure accumulator is controlled by the use of different solenoid valves. 
     German Laid Open Patent Application DE 102007056684 A1 of the applicant presents a pressure accumulator with a separate housing. 
     German Laid Open Patent Application DE 10228354 A1 further describes a pressure accumulator integrated in an inner cavity, wherein installation space in the internal combustion engine can be spared. 
     SUMMARY 
     Accordingly, the objective of the present invention relates to refining conventional pressure accumulators for supplying pressure to loads in internal combustion engines in an advantageous manner. 
     This and other objectives are met according to the proposal of the invention by a switchable device for supplying pressure with the features of the main claim. Advantageous constructions of the invention are specified by the features of the subordinate claims. 
     According to the invention, a switchable device for supplying pressure (switchable pressure accumulator) to at least one load of an internal combustion engine is shown. The load can involve, in particular, a hydraulic camshaft adjuster for adjusting the phase position between the crankshaft and camshaft. It is also conceivable, however, that the device is used, for example, in an electrohydraulic valve actuation device of an internal combustion engine. 
     The device for supplying pressure comprises a housing with a cavity. The cavity can involve, for example, an inner cavity of a camshaft, so that the camshaft forms the housing of the switchable device. Alternatively, a housing with a cavity that is different from the hollow camshaft could also be provided, wherein this housing is then inserted into an inner cavity of the camshaft. 
     The device for supplying pressure further comprises a displacement element that is arranged in the housing cavity and can be displaced between a first end position and a second end position. The displacement element has a pressure surface that at least partially defines a storage space that can be connected or is connected in a fluid-conducting manner to the load together with a wall of the housing cavity. For example, the storage space is connected to the lubricating oil circuit of the internal combustion engine, wherein an oil pump is used as the pressure source and oil of the lubricating oil circuit is used as pressurized medium. The displacement element can be constructed, for example, in the form of a piston with an end-side pressure surface. 
     The device according to the invention further comprises a force accumulator that interacts with the displacement element so that the displacement element can be displaced by pressurization of the storage space against the force of the force accumulator from the first end position into the second end position. The force accumulator is constructed, for example, as a spring element, in particular, in the form of a compression spring, wherein any other suitable spring type could also be used. 
     The device according to the invention further comprises a locking mechanism through which the displacement element can be locked detachably in the second end position in which the force accumulator is in tension. In one position of the displacement element different from the second end position, in particular, in the first end position, the displacement element cannot be locked by the locking mechanism. 
     In addition, the device according to the invention comprises a switch mechanism that is actuated by an actuator and has a switch element that can be brought into at least two switch positions, wherein the switch element interacts with the locking mechanism so that the displacement element can be locked in a first switch position of the switch element both from an unlocked state and also can be unlocked from a locked state and in a second switch position of the switch element, can be neither locked in the unlocked state nor unlocked in the locked state. 
     For relatively low installation space requirements, the device according to the invention allows a more reliable and more secure supply of pressure to the loads of an internal combustion engine that is provided independent of the pressure in the lubricating circuit of the internal combustion engine. 
     In one advantageous construction of the device according to the invention, it comprises a ball carrier element that is connected rigidly to the housing and has a carrier cavity in which the switch element is held at least partially. Here, the ball carrier element has a plurality of openings in each of which a ball is held so that it can move in the radial direction. The balls contact an outer lateral surface formed by the switch element. In this construction of the device, the device further comprises a locking element that is connected rigidly to the displacement element and is provided with a locking section that can be led into engagement with the balls in the second end position of the displacement element, for example, in that it engages behind these balls, in order to lock the displacement element on the housing. On the other side, the locking element is not led into engagement with the balls in the first end position of the displacement body, so that the displacement element is not locked. In this construction of the device, a restoring element is also provided that is arranged so that the switch element can be displaced by the actuator relative to the ball carrier element against the force of the restoring element from the first switch position into the second switch position. The first restoring element is constructed, for example, as a spring element, in particular, in the form of a compression spring, wherein any other suitable spring type could also be used. In this construction of the device, the outer lateral surface of the switch element is provided with at least one recess that is allocated to the balls and is constructed and arranged so that the balls can be held at least partially in the recess in the second switch position of the switch element, so that the locking section is led out of engagement with the balls and the locking of the displacement element is released. On the other side, the balls are not held by the recess of the support surface in the first switch position of the switch element, so that the locking of the displacement element is maintained. 
     These measures allow a technically especially simple realization of the device according to the invention that is distinguished by an especially good response behavior. 
     In the above construction of the invention, it can also be advantageous if a securing element connected rigidly to the ball carrier element is arranged that forms a stop for a radially outward directed movement of the balls, such that the balls are held captively in the openings. In one technically simple realization of the securing element, it has a pot-shaped construction and is placed onto the ball carrier element from one side. Here, the securing element and the ball carrier element can be connected rigidly to each other, for example, by pressing. Thus the sliding element forms a captive securing device for the balls when these are not in engagement with the locking section of the locking element. 
     In another advantageous construction of the device according to the invention for supplying pressure, this is provided with a sealing element that seals the cavity to the outside and on which the force accumulator of the displacement element is supported. The sealing element can be used here especially for securing the position of the force accumulator. In this case it can also be advantageous if the ball carrier element is connected rigidly to the sealing element. In addition, it can be advantageous if the sealing element is provided with a passage opening in which a switch body that interacts with the switch element and can be actuated by the actuator is held in a displaceable manner. Through these measures, the device according to the invention can be realized in a technically especially simple way. 
     In another advantageous construction of the device according to the invention, the storage space can be connected or is connected to the pressure source and optionally to the load in a fluid-conducting manner with at least one leakage prevention device positioned in-between. The leakage prevention device is constructed so that it allows the through flow of the pressurized pressure medium while blocking the through flow of non-pressurized pressure medium that is merely at hydrostatic pressure. Thus, the leakage prevention device can prevent leakage from the storage space if pressure is not supplier by the pressure source, for example, in the event of insufficient output of the oil pump. The leakage prevention device can be used as a limit for the storage space and can form, in particular, a stop for the displacement element in the first end position. The construction of such a leakage prevention device is known to someone skilled in the art and is described in the patent literature, for example, in DE 19615076. 
     In another advantageous construction of the device according to the invention, the pressure source can be connected or is connected to the storage space in a fluid-conducting manner via a non-return valve that forms a block in the direction toward the pressure source. 
     The invention further extends to an internal combustion engine that is equipped with at least one device that can be switched as described above for supplying pressure to at least one load. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be explained in more detail with reference to an embodiment, wherein reference is made to the accompanying drawings. Elements that are identical or have identical actions are designated in the drawings with the same reference symbols. Shown are: 
         FIG. 1  is a schematic axial section view with an enlarged section showing an embodiment of the device according to the invention for supplying pressure, 
         FIG. 2  is a schematic overview diagram, with reference to which the connection of the device for supplying pressure from  FIG. 1  to the lubricating oil circuit of an internal combustion engine is illustrated, 
         FIGS. 3A-3E  are enlarged axial section views for illustrating the locking of the device for supplying pressure from  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  and  FIG. 2  will be considered first, wherein an embodiment of the device according to the invention for supplying pressure to loads of an internal combustion engine, as well as the connection of the device to the lubricating oil circuit of an internal combustion engine, are shown. The device designated overall with the reference number  1  can be inserted in a camshaft cavity  5  of a hollow camshaft  6 . The camshaft  6  that is built-up as an example here and is provided with a plurality of cams  25  on its outer peripheral surface can be rotated about a central rotational axis  7 . The same would also be conceivable, however, if the camshaft  2  was produced in the foundry process. 
     The device  1  for supplying pressure to loads of an internal combustion engine comprises a hollow cylindrical housing  2  (“cartridge”) that is constructed with an interference fit relative to the camshaft cavity  5 , so that the device  1  can be easily integrated into the camshaft  6  by inserting the housing  2  into the camshaft cavity  5  and connecting it rigidly to the camshaft  6 . 
     The housing  2  forms a housing cavity  3  in which a displacement element constructed in the form of a piston  4  is held so that it can be displaced in the axial direction. A sealing body  7  is further pressed in the housing cavity  3 , wherein this sealing body is constructed in the shape of a stepped cylinder and extends from one end of the housing  2  into the housing cavity  3 . It can be divided into a terminal first section  8  with larger diameter and an adjacent second section  9  with smaller diameter, wherein a ring stage  10  is produced. A force accumulator spring (helical compression spring)  11  used as a force accumulator is supported with one of its ends on the ring stage  10 . With its other end, this force accumulator contacts the piston  4 . 
     The sealing body  7  connected rigidly to the housing  2  is provided with a central axial bore  12  in which a switch rod  13  is held so that it can be displaced in the axial direction. The switch rod  13  can be actuated by an electromagnetic actuator  14 , wherein a tappet that is not shown in more detail engages an end-side contact surface of the switch rod  13  for this purpose. The switch rod  12  is part of a switch mechanism for locking and releasing a locking mechanism for the piston  4  that will be explained in more detail farther below. The piston  4  has an end-side pressure surface  15  that at least partially defines a storage space  17  for pressurized oil  28  together with a housing cavity wall  16  of the housing cavity  3 . 
     Opposite the actuator  14 , a hydraulic camshaft adjuster  18  is attached, for example, by means of a (not shown) central screw to the end side of the camshaft  6 . As usual, the hydraulic camshaft adjuster  18  comprises a drive part in drive connection with the crankshaft via a drive wheel and a camshaft-fixed driven part, as well as a hydraulic actuating drive that is located between the drive part and the driven part and transfers the torque from the drive part to the driven part and allows an adjustment and fixing of the rotational position between these parts. The hydraulic actuating drive is provided with at least one pressure chamber pair that act against each other and can be selectively pressurized with pressurized oil, in order to generate a change in the rotational position between the drive part and driven part by generating a pressure drop across the two pressure chambers. Hydraulic camshaft adjusters as such are well known to someone skilled in the art and described in detail, for example, in publications DE 202005008264 U1, EP 1596040 A2, DE 102005013141 A1, DE 19908934 A1, and WO 2006/039966 of the applicant, so that more exact details do not need to be discussed here. 
     As can be taken from the overview diagram of  FIG. 2 , the hydraulic camshaft adjuster  18  and the storage space  17  are connected in a fluid-conducting manner to a pressure source or pressurized medium source constructed in the form of an oil pump  20  via a pressure line  19 . Here, the pressure line  19  is connected to radial openings  26  of the camshaft  6  opening into the camshaft cavity  5 . The oil pump  22  can thus feed pressurized oil from an oil tank  21  to the camshaft adjuster  18  and storage space  17 . A non-return valve  22  that is arranged in the pressure line  19  and forms a block in the direction toward the oil pump  20  prevents a return flow of pressurized oil in the case of reduced or insufficient output from the oil pump  20 . 
     In the central screw for fastening the camshaft adjuster  18  to the camshaft  6 , a control valve not shown in more detail is arranged for controlling the oil flows. This control valve can connect the pressure chambers of the camshaft adjuster  18  in a fluid-conducting manner selectively with the oil pump  20  or with the oil tank  21 . Such control valves are well known as such to someone skilled in the art and described in detail, for example, in the German Patent DE 19727180 C2, the German Patent DE 19616973 C2, the European Patent Application EP 1 596 041 A2, and the German Laid Open Patent Application DE 102 39 207 A1 of the applicant, so that more exact details do not have to be discussed here. 
     In the device  1 , the storage space  17  communicates with the hydraulic camshaft adjuster  18  or its control valve. In addition, additional loads are connected to the lubricating oil circuit, such as support elements  23  and bearing points  24  of the camshaft  6  that must be supplied with pressurized oil. Although this is not shown in the figures, a leakage prevention device for limiting the storage space  17  could be provided that could be used, in particular, as a stop for the piston  4 . 
     In the device  1 , the piston  4  can be pushed in the axial direction against the spring force of the force accumulator spring  11  by pressurization of the storage space  17 , in that pressurized oil is fed by the oil pump  20  via the pressure line  19  into the storage space  17 . Here, the piston  4  is pushed from a first end position into a second end position in which the force accumulator spring  11  is tensioned or is more strongly tensioned in the event of a biasing tension. The storage space  17  is sealed oil-tight from the outside by means of ring seals that are not shown in more detail. 
     In the second end position, the piston  4  can be locked by a locking mechanism. The locking mechanism comprises a sleeve-shaped ball carrier  31  that is pressed into a sleeve-shaped end section  27  of the sealing body  7  and has a plurality of radial bores  29  arranged distributed in the peripheral direction. A ball  30  is held in each of these bores. Here, the bores  29  each have a larger diameter than the balls  30 , so that these are freely moveable in the radial direction in the bores  29 . The ball carrier  28  is connected rigidly to the sealing body  7 . 
     A pot-shaped securing body  31  having a base wall  33  and a hollow cylindrical sleeve part  32  is pressed onto the free end section of the ball carrier  28  opposite the sealing body  7 . Here, the sleeve part  32  of the securing body  31  is dimensioned so that it partially covers the radial bores  29  with a certain overlap, so that only a certain radially directed movement of the balls  33  is allowed. An additional, radially outward directed movement of the balls  30  is blocked by the sleeve part  32 , so that the balls  30  all remain held in the bores  29 . 
     A switch pin  35  coupled with the switch rod  13  that can be displaced in the axial direction is held in a carrier cavity  34  of the ball carrier  28  so that it can be displaced in the axial direction. The switch pin  35  has a first end surface  36  that is coupled with an end-side end of the switch rod  35 . A restoring spring  39  is further held in the carrier cavity  34 , wherein this restoring spring is supported with its one end on a second end surface  37  of the switch pin  35  opposite the first end surface  37  and is supported with its other end on an inner surface  38  of the base wall  33  of the securing body  31 . The restoring spring  39  is here constructed, for example, as a helical compression spring, but could also be any other suitable type of spring. The switch pin  35  can thus be displaced in the axial direction by moving the switch rod  13  by the tappet of the actuator  14  against the spring force of the restoring spring  39 . Here, the tappet acts on the end-side contact surface of the switch rod  13 , wherein the tappet is connected rigidly to a magnetic armature of an electromagnet of the actuator  14  and can be displaced in the axial direction by energizing the magnetic armature. If the magnetic armature is not energized, the switch pin  35  is restored by the spring force of the restoring spring  39 . 
     An outer lateral surface  40  of the switch pin  35  is provided with a peripheral ring groove  41  that is allocated to the balls  30  and is constructed with an interference fit relative to the balls  30 . The switch pin  35  can be moved back and forth by the opposite forces of the actuator  14  and restoring spring  39  between two end positions. In a first end position when the actuator  14  is not activated, the balls  30  are outside of the ring groove  41 . In a second end position when the actuator  14  is activated, the balls  30  can be inserted into the ring groove  41 . The balls  30  always contact the outer lateral surface  40  of the switch pin  35 , so that they are held in the bores  29  in connection with the securing body  31  in a captive manner. 
     A locking body  42  is pressed onto the piston  4 . The locking body  42  is provided with a hollow cylindrical sleeve section  43  that is placed on the pot-shaped piston  4  and on which a locking section  44  connects for this purpose. The sleeve section  43  is used for the axial guidance of the piston  4  within the housing cavity  3 . The locking section  44  tapers in steps in the direction toward the actuator  14 . Here, a first step  45  tapering toward the actuator  14  forms a ring-shaped support surface  47  for the force accumulator spring  11 . An adjacent, second step  46  tapering toward the actuator  14  forms a ring-shaped seating surface  48  for the balls  30 . A collar  52  that is formed on the second step  46  and extends radially relative to the second step  46  forms a contact surface  49  for the balls  30 . 
     A locking and unlocking process of the piston  4  of the device  1  will now be described, wherein reference will be made to  FIGS. 3A-3E . 
     If the storage space  17  is charged with pressurized oil by the oil pump  20 , the piston  4  is displaced by means of its pressure surface  15  against the spring force of the force accumulator spring  11  until the contact surface  49  of the locking body  42  is led into contact with the balls  30 . If the actuator  14  is not activated, the switch pin  35  is restored by the spring force of the restoring spring  39 . In this position of the switch pin  35 , the balls  30  are outside of the ring groove  41 . Here, the locking section  44  of the locking body  42  is sufficiently resistant to deformation, so that it cannot slide over the balls  30 . This situation is shown in  FIG. 3A . 
     If the actuator  14  is activated by the electromagnet being energized, the switch rod  13  is moved against the force of the restoring spring  39  by the tappet engaging the end-side contact surface. Here, the switch pin  35  is brought by the switch rod  13  into a position in which the ring groove  41  is on the radial inside of the bores  29  or balls  30 , so that the balls  30  can be inserted into the ring groove  41 . Thus, the balls  30  are pressed into the ring groove  41 , charged by the locking section  44 . The depth of the ring groove  41  is dimensioned so that the piston  4  or the locking section  44  connected rigidly to the piston  4  can be displaced even farther against the spring force of the force accumulator spring  11 . For example, the balls  30  are held completely within the bores  29  and seal at least approximately flush with an outer lateral surface of the ball carrier  28 . This situation is shown in  FIG. 3B . 
     If the piston  4  is displaced father against the spring force of the force accumulator spring  11 , charged by the pressurized oil in the storage space  17 , an end-side contact surface  50  of the locking body  42  is finally led into contact with an end-side contact surface  51  of the sealing body  7 . This defines an end position (designated “second end position” in the introduction of the description) of the piston  4  in which the storage space  17  is filled with a maximum amount of pressurized oil. If the actuator  14  is no longer activated, i.e., if the electromagnet is no longer energized, the switch pin  35  is displaced in the axial direction relative to the ball carrier  28  by the spring force of the restoring spring  39 , wherein the balls  30  are pressed out from the ring groove  41  against the seating surface  48  of the locking section  44 . In this position, the locking section  43  engages behind the balls  30 , so that the piston  4  is fixed in the axial direction. This situation is shown in  FIG. 3C . 
     The piston  4  can thus be locked in its second end position only by activating the tappet for displacing the switch pin  35  against the spring force of the restoring spring  39  from the first switch position into the second switch position. The piston  4  cannot be locked without displacing the switch pin  35  into the second switch position. 
     Starting from a locked piston  4  as shown in  FIG. 3C , if the actuator  14  is now activated by the electromagnet being repeatedly energized, the switch rod  13  is moved against the force of the restoring spring  39  by the tappet contacting the end-side contact surface. Here, the switch pin  35  is brought into the second switch position by the switch rod  13  in which the ring groove  41  is radially inside of the bores  29  or balls  30 , so that the balls  30  can be inserted into the ring groove  41 . The balls  30  are then pressed into the ring groove  41 , charged by the spring force of the force accumulator spring  11 , by means of the locking section  44 . This has the result that the locking section  44  no longer engages behind the balls  30  and the locking of the piston  4  is released. This situation is shown in  FIG. 3D . 
     This has the result that the piston  4  is displaced by the spring force of the force accumulator spring  11 , wherein pressurized oil is discharged from the storage space  17  to the hydraulic camshaft adjuster  18 . The piston  4  is displaced, charged by the spring force, until it comes into contact with a stop  53  formed by the camshaft  6 , which defines an end position of the piston  4  (designated as “first end position” in the introduction of the description). Movement of the piston  4  between the two end positions corresponds to a maximum piston stroke of the piston  4 , which specifies the maximum displaced volume. Alternatively, a leakage prevention device could be used as an end stop for the piston  4 . 
     The piston  4  can thus be unlocked first by activating the tappet for displacing the switch pin  35  against the spring force of the restoring spring  39  from the first switch position into the second switch position. The piston  4  cannot be unlocked without displacing the switch pin  35  into the second switch position. 
     In the device according to the invention, a piston integrated into a cavity of the camshaft by means of a separate housing can thus be biased by the pressure of the oil pump when the internal combustion engine is running against the force accumulator spring up to a specified stroke. In this position, the piston is engaged through short activation of the radially decoupled actuator that is mounted outside of the camshaft in a holding mechanism (ball locking). When the internal combustion engine is turned off, the oil pressure in the oil galleries falls to ambient pressure, just like the pressure in the pressure accumulator. Energy is still stored in the force accumulator spring. Through an optional leakage prevention device, the “pressure-free” lubricating oil cannot be returned from the storage space into the oil galleries or via the camshaft bearing points into the cylinder head. A plate-labyrinth leakage prevention device consisting of three plates each with a bore in the axial direction on the outer diameter is used, for example, as the leakage prevention device. The plates are rotated by 120° relative to each other. The pressure accumulator has no pressure loss due to leakage. Complicated high-pressure seals are eliminated. In this way, the system friction is reduced and more usable energy is stored in the force accumulator spring. On the other hand, through short activation of the actuator, the locking mechanism of the piston can be released. By means of the biased force accumulator spring, the oil is pressed out from the storage space back into the oil circuit of the cylinder head and the camshaft adjuster, assuming that the supply oil pressure in the oil galleries is less than the pressure that can be achieved with the pressure accumulator (spring element force multiplied with piston pressure surface area). To prevent a return flow of the oil in the direction of the oil pump during discharge, a non-return valve that forms a block in the direction of the oil pump is provided between the oil pump and the loads that are to be loaded with oil pressure from the pressure accumulator. 
     In the device according to the invention, the piston is guided in the axial direction in the housing and is supported on the sealing body by means of a spring element (e.g., tensile or compression spring) that is pressed into the housing. The ball carrier is pressed into the sealing body. This has, for example, eight radial bores in each of which a ball is guided. The switch rod is coupled with the switch pin and supported so that it can be displaced in the axial direction in the sealing body. The actuator is screwed, for example, in the cylinder head and presses on the switch rod against the restoring spring of the switch pin in the energized state. The connection of the switch rod/camshaft is realized by means of a radial decoupling. The securing body is used for captive securing of the balls. The arrangement in the cavity of the camshaft produces an advantage in terms of installation space compared with pressure accumulators arranged external to the camshaft. 
     The device according to the invention allows a reliable supply of pressure to loads of an internal combustion engine, wherein pressurized oil is made available through the pressure accumulator integrated in the camshaft independent of the engine oil supply (lubricating oil circuit) of the internal combustion engine. Thus, loads can be supplied with pressurized oil even if the engine-side oil supply is not sufficient, for example, when the engine is started and in the event of very hot pressurized oil in connection with a low output of the oil pump (hot idling). In particular, immediately after the start of the internal combustion engine, an adjustment of the camshaft adjuster into the base position (retarded, middle, advanced position) can be realized, which is especially suitable in connection with start/stop systems. In addition, the adjustment rate of the camshaft adjuster can be improved especially for hot idling of the internal combustion engine. The device according to the invention can be realized by relatively few components, which can save costs in terms of assembly and materials in industrial series production. One special advantage of the device is given from the fact that the piston can be locked or unlocked by short activation of the actuator (current pulses). Permanent activation of the actuator in the locked or unlocked state of the piston is not necessary. This allows an especially energy-saving activation of the device for supplying pressure. 
     LIST OF REFERENCE SYMBOLS 
     
         
           1  Device 
           2  Housing 
           3  Housing cavity 
           4  Piston 
           5  Camshaft cavity 
           6  Camshaft 
           7  Sealing body 
           8  First section 
           9  Second section 
           10  Ring step 
           11  Force accumulator spring 
           12  Axial bore 
           13  Switch rod 
           14  Actuator 
           15  Pressure surface 
           16  Housing cavity wall 
           17  Storage space 
           18  Camshaft adjuster 
           19  Pressure line 
           20  Oil pump 
           21  Oil tank 
           22  Non-return valve 
           23  Support element 
           24  Bearing point 
           25  Cam 
           26  Radial opening 
           27  End section 
           28  Ball carrier 
           29  Bore 
           30  Ball 
           31  Securing body 
           32  Sleeve part 
           33  Base wall 
           34  Carrier cavity 
           35  Switch pin 
           36  First end surface 
           37  Second end surface 
           38  Inner surface 
           39  Restoring spring 
           40  Outer lateral surface 
           41  Ring groove 
           42  Locking body 
           43  Sleeve section 
           44  Locking section 
           45  First step 
           46  Second step 
           47  Support surface 
           48  Seating surface 
           49  Contact surface 
           50  Contact surface of the locking body 
           51  Contact surface of the sealing body 
           52  Collar 
           53  Stop