Abstract:
A valve lever assembly having a switchable valve actuating mechanism comprises a first follower surface for following a first cam, at least one second follower surface for following a second cam and a valve lever, which is supported on an engine-affixed component and on the to-be-actuated valve, wherein the second follower surface is rotatable relative to the first follower surface by a lockable eccentric device borne on the valve lever and the eccentric device comprises an eccentric opening, which penetrates transversely through the valve lever and is fixed relative to the valve lever to as to rotate therewith, and an eccentric shaft rotatably borne in the eccentric opening, the eccentric shaft defining the position of the second follower surface.

Description:
CROSS-REFERENCE 
       [0001]    This application is a U.S. non-provisional application claiming the benefit under 35 U.S.C. § 119 (e)(1) to U.S. provisional application 61/026,901, having a filing date of Feb. 7, 2008. This application is also related to German application DE 10 2008 008 094.2-13. 
     
    
     TECHNICAL FIELD 
       [0002]    The invention concerns a valve lever assembly having a switchable valve actuating mechanism, as is used, e.g., in reciprocating-piston, internal combustion engines, for changing the engine valve timing of an intake valve. 
       BACKGROUND 
       [0003]    Switchable valve actuating mechanisms are utilized in many ways and serve to adapt the engine valve timing to different operating conditions in order to favorably influence the power development, the torque performance and the exhaust gas properties of the internal combustion engine. 
         [0004]    A valve lever assembly having a switchable valve actuating mechanism for acting in combination with a camshaft having a first cam and second cam, which second cam is higher than the first cam is known from DE 10 2005 039 368 A1. In this valve lever assembly, the eccentric device includes an eccentric body rotatably borne in the valve lever; bearing pins disposed in the valve lever eccentrically to its bearing axis project from both sides of the eccentric body; follower rollers, each for following a respective second cam, are borne on the eccentric pins. The pivotability of the eccentric body relative to the valve lever is lockable by means of a connection lever that is connected with the eccentric body so as to rotate therewith. 
         [0005]    The object underlying the invention is to simplify the construction and assembly of a conventional valve lever assembly. 
       SUMMARY 
       [0006]    This object is achieved with a valve lever assembly having a switchable valve actuating mechanism for acting in combination with a camshaft having a first cam and at least one second cam, which is higher than the first cam, which valve assembly comprises a first follower surface for following the first cam, at least one second follower surface for following the second cam and a valve lever, which is supported on an engine-affixed component and on the to-be-actuated valve, wherein the second follower surface is rotatable relative to the first follower surface by an eccentric device borne on the valve lever, and a locking mechanism, with which the rotatability of the eccentric device is lockable, wherein when the eccentric device is freely rotatable, the first follower surface actuates the valve in accordance with the contour of the first cam and when the rotatability of the eccentric shaft is locked, the second follower surface actuates the valve in accordance with the contour of the second cam, and wherein the eccentric device comprises an eccentric opening, which penetrates transversely through the valve lever and is fixed relative to the valve lever to as to rotate therewith, and an eccentric shaft rotatably borne in the eccentric opening, the eccentric shaft defining the position of the second follower surface. 
         [0007]    According to a second aspect of the invention, the eccentric opening has a cross-sectional profile with a concave bearing segment that is opposite to a concave guide segment, which is less sharply curved than the bearing segment, and the eccentric shaft includes a bearing portion in a bearing part of the eccentric shaft, which eccentric shaft is accommodated in the eccentric opening, the outer contour of the bearing portion being adapted to that of the bearing segment, and the eccentric shaft also includes a guide portion, whose outer contour is adapted to the guide segment so that the eccentric shaft is reciprocally rotatable in the eccentric opening while rotating in the bearing segment and while being guided along the guide segment. 
         [0008]    According to third aspect of the invention, the bearing segment includes a first circular segment having a first curvature of radius and the guide segment includes a second circular segment having a second curvature of radius, which is larger than the first curvature of radius, and the two circular segments have a common curvature center point, through which the eccentric shaft extends. 
         [0009]    According to a fourth aspect of the invention the cross-sectional profile of the bearing portion includes a portion corresponding to the first circular segment. 
         [0010]    According to a fifth aspect of the invention the cross-sectional profile of the guide portion includes a portion corresponding to the second circular segment. 
         [0011]    According to a sixth aspect of the invention an abutment segment is formed in a transition segment between the guide segment and the bearing segment, the abutment segment limiting the rotatability of the eccentric shaft. 
         [0012]    According to a seventh aspect of the invention a segment of the eccentric opening that is opposite to the abutment segment widens as an insertion segment such that the eccentric shaft is slidable into the eccentric opening in a rotational position relative to the eccentric opening, in which the bearing portion is facing towards the abutment segment, and from this rotational position is rotatable into a rotational position, in which the bearing portion is accommodated in the bearing segment and the guide portion comes into abutment on the guide segment. 
         [0013]    According to an eight aspect of the invention the eccentric opening is formed in an eccentric bearing body disposed in the valve lever so as to rotate therewith. 
         [0014]    According to a ninth aspect of the invention the first follower surface is formed by the circumferential surface of a follower roller borne on the eccentric bearing body. 
         [0015]    According to a tenth aspect of the invention the eccentric shaft includes a pin defining the position of the second follower component axially adjacent to the bearing of the eccentric shaft in the eccentric opening, the eccentric shaft being elastically biased in the direction of abutment of the second follower surface on the second cam and being lockable by the locking mechanism when the second follower surface abuts on the base circle of the second cam. 
         [0016]    According to an eleventh aspect of the invention the second follower surface is formed by the circumferential surface of a follower roller borne on the pin. 
         [0017]    According to a twelfth aspect of the invention the locking mechanism includes a connecting lever connected with the eccentric shaft so as to rotate therewith, the position of the connecting lever being lockable relative to the valve lever when the second follower surface abuts on the base circle of the second cam. 
         [0018]    According to a thirteenth aspect of the invention the eccentric shaft is integrally formed with the connecting lever and the pin. 
         [0019]    According to a fourteenth aspect of the invention a locking component is mounted on the valve lever, the locking component being reciprocally movable between a position locking the rotatability of the connecting lever and a position permitting the pivotability. 
         [0020]    According to a fifteenth aspect of the invention the locking component is formed as a locking pin, which is displaceable by hydraulic pressure against the force of a spring. 
         [0021]    According to a sixteenth aspect of the invention a spring lever is borne on the valve lever, which spring lever is in engagement with the eccentric shaft and is biased by a spring supported between the valve lever and the spring lever such that the second follower surface is biased in the direction of abutment on the second cam. 
         [0022]    According to a seventeenth aspect of the invention a second follower surface is formed on both sides of the bearing of the eccentric shaft in the eccentric opening, the respective second follower surfaces acting in combination with the respective second cams. 
         [0023]    According to an eighteenth aspect of the invention the engine-affixed component, on which the valve lever is supported, is formed as a hydraulic valve play-compensation element, through which the locking mechanism is actuatable by hydraulic pressure. 
         [0024]    The aspects of the invention as mentioned above may be combined in different manners. E.g. the fifth aspect may be combined with the third or the fourth aspect; the sixth aspect may be combined with any of the second to fifth aspect; the eighth aspect may be combined with any of the preceding aspects; the tenth aspect may be combined with any of the preceding aspects; the twelfth aspect may be combined with any of the preceding aspects; the sixteenth to eighteenth aspect may also be combined with any of the preceding aspects. 
         [0025]    The invention, which can be utilized for substantially all types of cam shafts and allows a switching between two different opening curves, of which one can be a neutral actuation, will be described in an exemplary manner in the following with the assistance of schematic drawings and with further details. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0026]      FIG. 1  shows an overall view of a valve drive having an inventive valve lever assembly, 
           [0027]      FIGS. 2-3  show different perspective views of the valve lever assembly of  FIG. 1 , 
           [0028]      FIG. 4  shows the valve actuating mechanism according to  FIGS. 1-3  in an exploded illustration, 
           [0029]      FIG. 5  shows a perspective illustration of the cam shaft, 
           [0030]      FIG. 6  shows a perspective illustration of the eccentric bearing body, 
           [0031]      FIG. 7  shows a side view of the eccentric bearing body, 
           [0032]      FIG. 8  shows the view of  FIG. 7 , with a cross-section of the cam shaft disposed in the eccentric opening, 
           [0033]      FIG. 9  shows a perspective illustration for explaining an assembly sequence, 
           [0034]      FIG. 10  shows a perspective view for explaining the functions of a locking pin, 
           [0035]      FIG. 11  shows a section through parts of the locking device disposed in the valve lever, 
           [0036]      FIG. 12  shows a view similar to  FIG. 1  of a modified embodiment of the actuating mechanism, and 
           [0037]      FIG. 13  shows a perspective view of a spring lever. 
       
    
    
     DETAILED DESCRIPTION 
       [0038]    In accordance with  FIG. 1 , a charge changing valve  2 , e.g., an intake valve of an internal combustion engine, is actuated by a cam shaft  4  by disposing between them a valve lever assembly, which is denoted as a whole with  5 , having a valve lever  6 . One end of the valve lever  6  is supported on a known hydraulic valve play-compensation element  8  and the other end is supported on the shaft of the valve  2  and the valve lever  6  abuts on cams  12  and  14 , respectively, of the cam shaft  4  between its ends in a manner that will be further described below. As is apparent, a middle first cam  12  is designed with a smaller elevation than the side second cams  14 . A valve closing spring is denoted with  16 . The hydraulic valve play-compensation element  8  causes the valve lever  6  to contact at least one of the cams and the shaft of the valve without play. 
         [0039]      FIG. 2  shows the valve lever assembly  5  obliquely from below and with the end of the valve lever  6 , which is supported on the valve play-compensation element  8 , facing the observer. 
         [0040]      FIG. 3  shows the valve lever assembly  5  in a perspective illustration obliquely from above. 
         [0041]    For the purpose of clarity, the individual parts of the valve lever assembly are not provided with reference numbers in  FIGS. 1-3 . 
         [0042]      FIG. 4  shows the valve lever assembly according to  FIG. 1  with its individual parts in exploded illustration: 
         [0043]    The valve lever  6  has two end portions  18  and  20  that are connected with each other via spaced-apart side parts  22 . As is apparent from  FIG. 2 , the under side of the valve lever  6  is advantageously closed. An opening  24  extends transversely through the side parts  22 ; an eccentric bearing body  26  is insertable in the opening  24 . The end portion  28 , which lies on the valve play-compensation element  8 , is hollow in the interior and has a passage opening  28 . 
         [0044]    The eccentric bearing body  26  is provided with an eccentric opening  30  penetrating transversely therethrough, whose cross-section will be explained in more detail with the assistance of  FIGS. 6 and 7 . 
         [0045]    The eccentric opening  30 , whose cross-section as a whole approximately has the shape of a kidney with a bulge, comprises a concave bearing segment  31  and a concave guide segment  32  opposing the bearing segment  31 , wherein the curvature of the guide segment  32  is less sharp than the curvature of the bearing segment  31 . The bearing segment  31  comprises a first circular segment  31 ′ having a curvature central point  33 . The guide segment  32  comprises a second circular segment  32 ′, whose curvature center point is also provided by the curvature central point  33 . The guide segment  32  transitions into the bearing segment  31  via a transition segment  34 , wherein the transition portion  34  is initially formed with a sharp curvature, then is curved less sharply, wherein the less sharply curved segment forms an abutment segment line, and then transitions into the bearing segment  31  via a slightly concave-curved shoulder segment. 
         [0046]    On the side opposing the abutment segment  34 ′, the guide segment  32  transitions into the insertion segment  35  via a slightly concave- or even a convex-curved segment  37 ; the insertion segment  35  is designed as a circular-segment shape with a larger curvature radius than the curvature radius of the first circular segment  31 ′ and transitions into the bearing segment  31  via a convex-curved shoulder segment  38 . 
         [0047]    An eccentric shaft denoted as a whole with  40  is insertable into the eccentric opening  30 ; the eccentric shaft includes a middle bearing part  41 , whose cross-section is adapted to the cross-section of the eccentric opening  30 . As is apparent especially from  FIG. 8 , which shows in cross-section the bearing part  41  of the eccentric shaft  40  accommodated in the eccentric opening  30 , the bearing part  41  of the eccentric shaft includes a bearing portion  42 , whose outer contour is designed as a circular-segment shape with approximately the same radius as the radius of the first circular segment  31 ′ of the eccentric opening  30 . The bearing portion  42  transitions into a guide portion  43  via concave-curved lateral constrictions; the guide portion  43  has a curvature corresponding to the curvature of the second circular segment  32 ′ in its portion opposing the circular-segment-shaped-curved portion of the bearing portion  42 . An abutment portion  44 , which is formed on a side of the bearing part  41  between the bearing portion  42  and the guide portion  43 , abuts on the abutment segment  34 ′ of the eccentric opening  30  in the illustrated position of the bearing part  41 . 
         [0048]    The position of the bearing part  41  illustrated in  FIG. 8  corresponds to the position of the bearing part  41  that is farthest rotated in the counter-clockwise direction. The bearing part  41  can be rotated from this position about the curvature central point  33  in the clockwise direction, wherein the bearing portion  42  is borne in the bearing segment  31  and the guide portion  43  at least proximally abuts on the second circular segment  32 ′. 
         [0049]    The eccentric shaft  40  ends on both sides in bearing pins  46  that have a common axis denoted with  47  in  FIG. 8 . The terminal ends of the bearing pins  46  are provided with holes  48 . A connecting lever  50  is rigidly connected with the eccentric shaft  40 . The bearing part, the bearing pins and the connecting lever of the eccentric shaft  40  are advantageously constructed as a one-piece component. 
         [0050]    A first follower roller  52  is bearable on the outer surface of the eccentric bearing body  26  between the side parts  22  of the valve lever  6 . 
         [0051]    Two follower rollers  56  are bearable on the bearing pins  46  of the eccentric shaft  40  with annular washers  54  disposed in between. 
         [0052]    The kinematics of the described arrangement is advantageously such that the central point  47  and/or the axes of the bearing pins  46  move on a circular-segment-shaped path when the eccentric shaft  40  is reciprocally pivoted; the circular-segment-shaped path extends at least approximately through the central point  11  of the eccentric bearing body  26  that forms the rotational axis of the follower roller  52 . As is directly apparent from  FIGS. 7 and 8 , the available space inside of the eccentric body is utilized effectively due to the position of the curvature central point  33  eccentric relative to the central point  11  which curvature central point  33  forms the bearing axis of the eccentric shaft  40  and defines the movement path of the guide portion  43  in a central portion of the eccentric bearing body  26 . 
         [0053]    The end portion  20  of the valve lever  6  is formed with hollow cylindrical bearing arms  58 ; torsion springs  60  are slidable onto the bearing arms  58 . Bearing journals  62  are insertable into the bearing arms  58  and are formed on spring levers  64  that include projecting pins  46 , which are insertable into the holes  48  formed at the terminal ends of the bearing pins  46  with a clearance. 
         [0054]    A spacer sleeve  68  is slidable into and through the bearing journals  62 . The spring levers  64  are pivotably attachable to the valve lever  6  using a rivet  70 , whose shaft is slidable into and through the spacer sleeve  68 . When the spring levers  64  are mounted on the valve lever  6 , the torsion springs  60  are supported with each axial arm  72  on a side part  22  of the valve lever  6  and with each radial arm  74  on a bent lug  76 . The spring lever  64  according to  FIG. 4  is biased by the torsion springs  60  for rotation in the counter-clockwise direction relative to the valve lever  6  and thereby biasing the second follower roller  56  in the upward direction. 
         [0055]    A locking mechanism accommodated in the passage opening  28  of the end portion  18  of the valve lever  6  comprises a locking pin  80 , a spring  82 , a guide journal  84 , a retaining journal  86  and a retaining pin  88  insertable through the named components, which retaining pin  88  is affixable with a lock washer  90 . 
         [0056]    As is apparent especially from  FIG. 10 , the front end of the locking pin  80  is formed with a bevel  92  that advantageously corresponds to a corresponding bevel of the front end of the connecting lever  50 ; the front, lower end portion of the connecting lever  50  includes an contact area  94 , whose contour corresponds to the upper side  96  of the terminal end portion of the locking pin  80 . 
         [0057]    The outer circumference of the locking pin  80  is formed with a groove  96 . Similarly, the outer circumference of the eccentric bearing body  26  is formed with a groove  98 . The grooves  96  and  98  align with a groove  100  in a predetermined rotational position of the locking pin  80  and the eccentric bearing body  26 ; the groove  100  is laterally formed in the valve lever  6  and a locking pin  102  is accommodated therein; the locking pin  102  holds the locking pin  80  and the eccentric bearing body  26  so as to be not-pivotable relative to the valve lever  6 . The locking pin  102  is accommodated in the groove and the grooves  96 ,  98  and  100 , respectively, in a captive manner using a not-illustrated mechanism. 
         [0058]    The assembly of the valve lever assembly takes place, e.g., as follows: 
         [0059]    As shown in  FIG. 9 , the eccentric shaft  40  is inserted into the eccentric opening  30  in a rotational position, in which the guide portion  43  arrives in the insertion segment  35 . The bearing pin  46  can thereby be pushed through the insertion segment  35 , which has a large curvature radius and is thus widened ( FIG. 9   b ). When the eccentric shaft  40  is subsequently rotated in the counter-clockwise direction ( FIG. 9   c ), a step  104  ( FIG. 9   a ) formed between the guide segment  43  and the bearing pin  46  engages the edge of the eccentric opening  30  from below, so that the eccentric shaft  40  is held in an axially undisplaceable manner as a consequence of the connecting lever  50  and the step  104 . From this position, the eccentric shaft  40  can be reciprocally rotated and/or pivoted inside of the eccentric opening  30 . The rotational axis of the eccentric shaft  44 , which extends through the curvature central point  33  ( FIG. 8 ), is thus eccentric to the central axis of the eccentric bearing body  26 , so that the bearing pin  46  with its axis  47  pivots upwards and downwards relative to the outer circumferential surface of the eccentric bearing body when the eccentric shaft  40  is reciprocally pivoted. 
         [0060]    The assembly of the eccentric bearing body  26  and the eccentric shaft  40  is inserted into the opening  24  penetrating through the side parts  22 , wherein the first follower roller  52  is previously inserted between the side parts  22 ; due to the insertion of the eccentric bearing body  26 , the first follower roller  52  is borne on this eccentric bearing body  26 . Subsequently, the annular washers  54  are slid onto the bearing pins. Thereafter, the second follower rollers  56  are slid onto the bearing pins  46 . Subsequently, the torsion springs  60  are slid onto the bearing arms  58  and the spring arms  64  are attached and are pivotably affixed to the valve lever  6  using the spacer sleeve  68  and the rivet  70 , whereby the two follower rollers  56  are held in a captive manner and are resiliently biased on the valve lever  6  in the upwards direction. 
         [0061]    Subsequently, the locking mechanism shown in longitudinal section in  FIG. 11  is installed. As shown in  FIG. 11 , a guide journal  84  is first inserted into the passage opening  28  of the end portion  18  of the valve lever  6  such that it is disposed left of a pressurized fluid supply channel  106  according to  FIG. 11 . The spring  82 , the locking pin  80  and the retaining pin  88  are then inserted from the left. The retaining journal  86  is then affixed to the retaining pin  88  from the right using the lock washer  90 . The function of the locking mechanism is such that, when the pressurized fluid supply channel  106  is not under pressure, the spring  82  presses the locking pin  80  out of the passage opening  28  and such that, when the pressurized fluid supply channel  106  is under pressure by building up pressure in the space between the guide journal  84 , through which the retaining pin  88  is movably guided in a sealed manner, and the retaining journal  86 , which is movably guided in the passage opening  28  in a sealed manner, the locking pin  80  is inwardly moved into the passage opening  28  against the force of the spring  82 . 
         [0062]    The function of the described valve lever assembly is as follows: 
         [0063]    It is first assumed that the locking pin  80  is disposed inside of the passage opening  28  by application of pressure to the pressurized fluid supply channel  106 , so that the spring lever  64  can reciprocally pivot together with the two follower rollers  56 , wherein the spring levers  64 , which engage with a clearance in the bearing pin  46  by means of the projecting pins  66 , can pivot upwardly and downwardly together with the second follower rollers  56  and this reciprocal movement takes place in a low friction and well-defined way due to the bearing of the eccentric shaft  40  in the eccentric opening  30 . 
         [0064]    The second follower rollers  56  are continuously urged into abutment on the second cam  14  of the cam shaft  4  due to the biasing of the torsion springs  60 , wherein the cam lift of the second cam  14  is not transmitted to the valve lever  6 , because the second cams  14  can move upwardly and downwardly by pivoting of the spring lever and/or the eccentric shaft, without the valve lever following this movement. The valve lever  6  is thus actuated by the abutment of the first cam  12  on the first follower roller  52 . 
         [0065]    When the second follower rollers  56  abut on the base circle of the second cams  14  and thus are pivoted into their highest position, the contact area  94  of the connecting lever  50 , which is rigidly connected with the eccentric shaft  44 , is disposed directly above the passage opening  28 , so that the locking pin  80  moves out of the passage opening  28  by releasing pressure from the pressurized fluid supply channel and a downward movement of the second follower rollers  56  relative to the valve lever  6  by further rotation of the second cam  14  is locked. The valve lever  6  is thus actuated according to the contour of the second cam  14  when the pivotability of the connecting lever  50  relative to the valve lever  6  is blocked. The actuation forces generated thereby are lead directly into the valve lever  6  from the bearing pin  46  in the bearing portion  42  of the eccentric shaft  40  and from there via the eccentric bearing body  26 . 
         [0066]    In case the locking pin  80  is already moved out of the passage opening  20  when the front portion of the connecting lever  50  is located underneath or in overlap with the locking pin  80 , the connecting lever  50  can move the locking pin  80  against its bevel  92  and advantageously against the corresponding bevel of the connecting lever  50  back into the passage opening  28  during its upward movement, so that the terminal end of the connecting lever  50  upwardly moves until the contact area  94  moves directly over the locking pin  80  and this arrives outside of the passage opening  28  and the rotatability of the connecting lever  50  locks. 
         [0067]    The exemplary-described and very compactly-build valve lever assembly can be modified in various ways. The valve lever  6  as well as the eccentric shaft  40  can be constructed as cast parts. The eccentric shaft can have only one bearing pin with an accompanying follower roller for following only one second cam, wherein the described embodiment has the advantage that the valve lever is symmetrically depressed. The rotationally-affixed arrangement of the eccentric bearing body  26  in the valve lever  6  can take place by means of a direct form-fit between a contour of the eccentric bearing body  26  and the valve lever  6 . The follower rollers can be fonned as follower surfaces that are directly formed on the bearing pins and/or the outer surface of the eccentric bearing body. The eccentric bearing body can then be omitted as its own component. The first follower surface can be directly formed on the valve lever, which is directly fonned with the eccentric opening. The eccentric opening can be fonned without the widened insertion segment. 
         [0068]    The function of the connecting lever  50  can be undertaken by a spring lever, whose pivotability is locked by the locking mechanism. 
         [0069]      FIGS. 12 and 13  show an embodiment of the valve lever assembly  5 , in which the two spring levers  64  of the embodiment shown in  FIG. 4  are combined into one overall U-shaped spring lever  64 ′ that can be formed as a sheet metal part. As is apparent, the embodiment of  FIGS. 12 and 13  differs from the embodiment of  FIG. 4  in that the individual spring levers  64  of  FIG. 4  form arms  108  of the U, which are connected via a bridge  110 . In the embodiment of the spring lever of  FIG. 12 , the locking pin  80 , which is movable out of the valve lever  6 , can be, e.g., moved into a corresponding recess of the spring lever in the portion between the bridge  110  and the arms  108  or can come into abutment on a corresponding abutment surface. 
       REFERENCE NUMBER LIST 
       [0000]    
       
           2  Charge changing lever 
           4  Cam shaft 
           5  Valve lever assembly 
           6  Valve lever 
           9  Valve play-compensation element 
           12  First cam 
           14  Second cam 
           16  Closing spring 
           18  End portion 
           20  End portion 
           22  Side part 
           24  Opening 
           26  Eccentric bearing body 
           28  Passage opening 
           30  Eccentric opening 
           31  Concave bearing segment 
           31 ′ First circular segment 
           32  Concave guide segment 
           32 ′ Second circular segment 
           33  Curvature central point 
           34  Transition segment 
           34 ′ Abutment segment 
           36  Shoulder segment 
           37  Segment 
           38  Shoulder segment 
           40  Eccentric shaft 
           41  Bearing part 
           42  Bearing portion 
           43  Guide portion 
           44  Abutment portion 
           46  Bearing pin 
           47  Axis 
           48  Hole 
           50  Connecting lever 
           52  Follower roller 
           54  Annular washer 
           56  Second follower roller 
           58  Bearing arm 
           60  Torsion spring 
           62  Bearing journal 
           64  Spring lever 
           64 ′ Spring lever 
           66  Projecting pin 
           68  Spacer sleeve 
           70  Rivet 
           72  Axial arm 
           74  Radial arm 
           76  Lug 
           80  Locking pin 
           82  Spring 
           84  Guide journal 
           86  Retainer journal 
           88  Retainer pin 
           90  Lock washer 
           92  Bevel 
           94  Contact area 
           96  Groove 
           98  Groove 
           100  Groove 
           102  Locking pin 
           104  Step 
           106  Pressurized fluid supply channel 
           108  Arm 
           110  Bridge