Abstract:
An arrangement of a first structural component and a second structural component that are movable relative to one another and assume a defined stable position in at least two relative positions to one another has a locking device with at least two locking recesses and at least one locking nose interacting with the at least two locking recesses. The locking recesses are provided on the first structural component and the at least one locking nose is provided on the second structural component. The locking device provides securing forces of different magnitude for unlocking the at least one locking nose depending on a direction of relative movement of the first and second structural components relative to one another.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The invention relates to an arrangement of structural components that are movable relative to one another and assume a defined stable position by means of a locking device in at least two relative positions. The locking device comprises at least two locking recesses and at least one locking nose or at least one locking recess and at least two locking noses, wherein on the first structural component the locking recess or recesses and on the second structural component the locking nose or noses are provided.  
         [0002]     In adjusting mechanisms, at least two structural components are generally moved relative to one another; often it is required to provide a stable position in predetermined relative positions to one another. Starting from this stable position, it is possible, by overcoming a securing force, to move the structural components relative to one another and allow them to assume another position. For securing them in a defined stable position locking devices are often provided, i.e., one of the structural components has a locking recess and the other structural component has a locking nose.  
       SUMMARY OF THE INVENTION  
       [0003]     It is an object of the present invention to provide an arrangement of the structural components of the aforementioned kind that provides improved handling of the structural components for moving the structural components.  
         [0004]     In accordance with the present invention, this is achieved in that the locking device is designed such that, as a function of the actuating direction for unlocking, the securing forces to be applied are of different magnitude.  
         [0005]     As a result of the arrangement according to the invention, the required forces for adjusting the structural components relative to one another are different as a function of the actuating direction, i.e., for the unlocking action securing forces of different magnitude must be overcome.  
         [0006]     According to a preferred configuration of the invention, these securing forces of different magnitude are realized in that the locking nose and/or locking recess has an asymmetric cross-sectional shape. In this way, flatter or steeper contours can be provided in one or the other direction; the contours, in addition to the basic shape of the locking nose or the locking recess, have a decisive effect in regard to the securing forces. Moreover, it is expedient to load the locking nose in the locking direction or catch direction by a spring. In this connection, the spring force is also a determining factor for the securing force of the locking device; the spring is, for example, configured as an elastic (springy) arm on which the locking nose is formed or the spring can be an additional component that acts on the locking nose.  
         [0007]     The shape of the locking nose and/or locking recess can be designed in accordance with the desired conditions wherein, as already mentioned, asymmetric or symmetric shapes can be selected. For example, the locking nose and/or locking recess can have an arc-shaped curved cross-sectional shape or can be designed as a triangular cross-sectional shape. In addition, trapezoidal cross-sectional shapes are considered particularly advantageous wherein an irregular trapezoid is of particular importance, i.e., a shape provided with slanted surfaces of different incline or surfaces of different length that in this way contribute, in addition to other effects, to the difference in magnitude of the securing forces.  
         [0008]     A particularly suitable configuration of the arrangement according to the invention is provided when the first and second structural components form a swivel joint wherein in a first joint part a circular recess is provided in which a rotary body is received that can be rotated by a second joint part and wherein the locking device is provided on the circumferential wall of the recess and the outer circumference of the rotary body. Such a swivel joint can be used in many applications. By means of the angular spacing of the locking recesses relative to one another, the rotary angle of the defined stable position is predetermined also. In this connection, it is also possible to arrange several locking recesses at different spacings to one another. The circular recess with a rotary body arranged therein and the arrangement of the locking device in the circumferential area between these parts results in a compact configuration.  
         [0009]     For further improving the function, it is expedient to provide the locking device with three locking recesses and three locking noses that are arranged staggered by an angle of 120 degrees relative to one another, respectively, and form three locking units. In this way, locking or catching of the three locking noses is realized simultaneously at a certain position and the respective securing force is generated commonly by the three locking noses. Alternatively, an arrangement of the locking units (locking recess and interacting locking nose) can be designed such that they are staggered by 180 degrees relative to one another in relation to the circular movement path. In another embodiment, it is provided that the locking noses are formed on springy arms on the outer circumference of the rotary body wherein these arms spring radially outwardly and in this way move the locking noses into the locking recesses. Expediently, the rotary body is a separate component and is connected to the second joint part for common rotation. In this way, the rotary body and the second joint part can be produced from different materials.  
         [0010]     According to a first configuration, the rotary body can be a ring wherein the connection for common rotation comprises an inner toothing on the ring and a ring gear on the second joint part. Alternatively, it is also possible to configure the rotary body as a round disk and to connect it positively to the second joint part. For this purpose, openings are provided in the disk into which matching projections of the second joint part that extend in the axial direction are inserted.  
         [0011]     A simple connection of the first and second joint parts is realized in that on the bottom of the circular recess a central pin or a central sleeve is provided and the ring gear of the second joint part is provided with a central bore by which the second joint part is supported on the central pin of the central sleeve. For providing a simple connection of the swivel joint to additional structural components, it is expedient to provide the first and second joint parts with sockets for inserting them into connecting components.  
         [0012]     The arrangement according to the invention of structural components with locking devices can, of course, also be provided on differently formed surfaces of the components sliding past one another, for example, on plane surfaces. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0013]      FIG. 1  is an exploded view of a locking device provided on a swivel joint.  
         [0014]      FIG. 2  is a view of a first joint part with locking recesses.  
         [0015]      FIG. 3A  is an enlarged illustration of the detail III of  FIG. 2  illustrating a first shape of the locking recesses.  
         [0016]      FIG. 3A  is an enlarged illustration of the detail III of  FIG. 2  illustrating a second shape of the locking recesses.  
         [0017]      FIG. 4  is a ring with locking noses supported on springy arms.  
         [0018]      FIG. 5A  is an enlarged illustration of a first shape of a locking nose.  
         [0019]      FIG. 5B  is an enlarged illustration of a second shape of a locking nose.  
         [0020]      FIG. 5C  is an enlarged illustration of a third shape of a locking nose.  
         [0021]      FIG. 6  shows the first joint part according to  FIG. 2  with inserted ring on which the spring arms with locking noses are provided.  
         [0022]      FIG. 7  is a view of the second joint part.  
         [0023]      FIG. 8  shows a disk with locking noses supported on springy arms.  
         [0024]      FIG. 9  is an illustration of the disk according to  FIG. 8  inserted into the receiving opening. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]      FIG. 1  shows a swivel joint that is provided with a locking device according to the invention. In a first structural component  1  a circular recess  3  is formed that has a substantially cylindrical wall  17  and a bottom  18 . A second component  2  is provided with a ring gear  14  and a projecting pin  15  that are inserted into the recess  3 . The second component  2  is designed such that it substantially closes off the recess  3 . Between the ring gear  14  and the wall  17  of the recess  3 , a rotary body  4  is provided that is connected to the ring gear  14  for common rotation. The first structural component  1  thus forms a first joint part  5  and the second structural component  2  forms a second joint part  6 . The rotary axis of the swivel joint comprised of the joint parts  5  and  6  is identified by reference character D.  
         [0026]     The rotary body  4  in the embodiment of  FIG. 1  is a ring  11  with an inner toothing  13 . The inner toothing  13  is provided for positive engagement of the ring gear  14 . On the outer circumference of the ring  11 , three springy arms  10  are provided at uniform spacing to one another; they extend in the same direction. On the free ends of the springy arms  10  a locking nose  9  is formed, respectively. The locking noses  9  are guided during rotary movement on the wall  17  of the recess  3 ; when reaching one of the locking recesses  8 , an automatic locking of the locking noses  9  in the locking recesses takes place. On the first joint part  5  a base  25  is formed on which a stop surface  21  is provided. Mirror-symmetrical to this arrangement, the second joint part  6  has a base  26  formed as a unitary part that has a stop surface  22 . The base  25  and the base  26  each have a socket  7  that serves for insertion into connecting parts. In the end position in which the two sockets  7  point in the same direction, the stop surfaces  21  and  22  rests against one another.  
         [0027]      FIG. 2  is a view of the first joint part  5  with the recess  3  as well as the unitary base  25  and the socket  7 . The recess  3  has a circular cross-section. Several locking recesses  8  and  28  are provided on the wall  17 . One locking recess  8  and one locking recess  28  together form a set of neighboring locking recesses, respectively. In the embodiment illustrated in  FIG. 2 , the locking noses of the rotary body (compare  FIG. 1 ) in one end position of the swivel joint are positioned within the locking recesses  8  and are moved out of the recesses  8  counterclockwise along the wall  17  until they lock or catch in the locking recesses  28 . This is the end position in which the sockets  7  of both joint parts  5  and  6  of the swivel joint point in the same direction. On the bottom  18  of the recess  3 , a central opening  16  is provided into which the pin  15  (illustrated in the  FIG. 1 ) of the second joint part  6  projects and in which the opening  16  and the pin  15  together form a slide bearing.  
         [0028]     In the  FIGS. 3A and 3B , the detail III of  FIG. 2  is illustrated in two different variants. The locking recess  28 ′ of the  FIG. 3A  is significantly smaller than the locking recess  28 ″ of  FIG. 3B  whose cross-sectional shape corresponds substantially to a semi-circle. The different shapes illustrate that the securing forces that are required for unlocking the locking device in the embodiment according to  FIG. 3A  are significantly smaller than for the significantly deeper locking recess  28 ″ of  FIG. 3B .  
         [0029]      FIG. 4  shows the rotary body  4  in an axial view. This rotary body  4  is comprised of a ring  11  with an inner toothing  13  and three arms  10  arranged on the outer side of the ring. Because of their design and their material, the arms  10  are springy in the radial outward direction; the illustration in  FIG. 4  shows the relaxed position of the springy arms  10 . On the free ends of the springy arms  10 , a locking nose  9  is formed, respectively. The springy arms  10  extend substantially in the circumferential direction of the ring wherein the free ends in the mounted state of the rotary body  4  are forced toward the center M of the rotary body  4 . The pretension generated in this way enhances the locking action of the locking noses  9  when they reach the locking recesses of the first joint part  5  illustrated in  FIGS. 1 and 2 .  
         [0030]      FIGS. 5A, 5B , and  5 C show different variants of the detail V in  FIG. 4 . The cross-sectional shape of the locking nose  9  in  FIG. 5B  has a curve or arc shape  23  with a substantially uniform curvature wherein the height of the curve or arc shape  23  is significantly smaller at the end connected to the springy arm  10  in comparison to the end facing away from it. In  FIG. 5A , the locking nose  9  has substantially the shape of a rectangle wherein the transition into the springy arm  10  has a slightly slanted lateral surface. In  FIG. 5C , a locking nose  9  is illustrated that has a substantially trapezoidal shape  24  wherein the lateral surfaces  27 ,  27 ′ of the trapezoid are positioned substantially at the same angle to the roof or top surface, and the respective surfaces  27 ,  27 ′ are different because of the different height ( 27  is longer than  27 ′) of the two sides ( 27 ,  27 ′) of the trapezoid.  
         [0031]      FIG. 6  shows the first joint part  5  with inserted rotary body  4  in a view identical to that of  FIG. 2 . The rotary body  4  according to the illustration of  FIG. 4  is a ring with an inner toothing  13  and the springy arms  10  are arranged on the outer circumference of the ring  11 . As illustrated in  FIG. 6 , the locking noses  9  are positioned in the locking recesses  28  and can be unlocked only by overcoming the securing force generated by the shape of the locking noses and locking recesses, respectively, as well as the spring force exerted by the arms  10 . Incidentally, identical parts are identified by the same reference numerals in the Figures.  
         [0032]      FIG. 7  shows a view of the second joint part  6  with ring gear  14  that engages the inner toothing  13  of the ring  11  shown in  FIG. 6 . When the first joint part  5  and the second joint part  6  are completely assembled, the pin  15  shown in  FIG. 7  is positioned in the opening  16  (shown in  FIG. 6 ) within the first joint part  5 .  
         [0033]     In  FIGS. 8 and 9 , an alternative configuration of the rotary body  4  is illustrated. This rotary body  4  comprises a disk  12  in which a central bore  19  is provided through which the pin  15  of the second joint part  6  projects. There are also four bores  20  in the disk  12  into which projections of the second joint part  6  project in order to transmit the rotary movement of the second joint part onto the rotary body  4 . In a further modification of the above described configuration, the rotary body  4  has at the circumference of the disk  12  four springy arms  10  with locking noses  9  provided at their free ends. While  FIG. 8  shows the rotary body  4  in the untensioned (relaxed) state, i.e., with unstressed springy arms  10 ,  FIG. 9  shows the mounted state, i.e., the rotary body  4  is inserted into the receiving opening  3 .  
         [0034]     Even though the invention has been explained with the aid of embodiments showing a swivel joint, use of the invention on differently designed surfaces of structural components gliding on one another is also conceivable, for example, surfaces that are plane or surfaces that have a uniform curvature.  
         [0035]     While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.