Abstract:
A locking device ( 10 ), for a vehicle seat ( 1 ), includes an indicating device ( 8 ) for indicating the locking state of the locking device ( 10 ). The indicating device ( 8 ) has a locking indicator ( 31, 32 ), which is visible when the locking device ( 10 ) is locked, and a release indicator ( 33, 34 ), which is visible when the locking device ( 10 ) is released. The indicating device ( 8 ) has at least one indicator arm ( 30 ), which is in the locking position when the locking device ( 10 ) is locked and which is in the release position when the locking device ( 10 ) is released. The indicator arm ( 30 ) includes an indicating area ( 39 ), which has a first locking indicator ( 31 ) and a first release indicator ( 33 ). A second release indicator ( 34 ), which is concealed by the indicator arm ( 30 ) when the indicator arm is in the locking position, is provided on a retaining plate ( 20 ).

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a United States National Phase Application of International Application PCT/EP2013/065723 filed Jul. 25, 2013 and claims the benefit of priority under 35 U.S.C. §119 of German Patent Applications DE 10 2012 015 236.1 filed Jul. 31, 2012 and DE 10 2012 020 269.5 filed Oct. 17, 2012, the entire contents of which are incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The present invention relates to a locking device for a vehicle seat having a display device for indicating a locking state, wherein the display device has at least one locking indicator which is visible when the locking device is locked, and at least one unlocking indicator, which is visible when the locking device is unlocked. The invention also relates to a vehicle seat having the locking device. 
     BACKGROUND OF THE INVENTION 
     A locking device of the generic type is known from WO 2004/069 585 A2. In order to unlock the locking device, there is provided an unlocking bolt which is constructed integrally with a securing element of the locking device. By pivoting the unlocking bolt about a bearing pin which acts as a pivot axis, the locking device can be unlocked. 
     For a user of the vehicle seat, it is extremely important that all the locking devices of the vehicle seat are fully locked. Otherwise, the vehicle seat can become disengaged from the vehicle structure in the event of a crash, which may lead to injuries to the user. An indication of the locking state of the locking device is therefore helpful for the user. 
     The locking state of the locking device can be identified from the angular position of the unlocking bolt. The unlocking bolt thus indicates whether the locking device is locked or unlocked. 
     However, the unlocking bolt is relatively small compared with the locking device and the vehicle seat. Furthermore, the unlocking bolts of the individual locking devices are arranged below the seat member of the vehicle seat at locations which are relatively difficult to see. Consequently, the locking state of the locking devices is relatively difficult to visually identify. In particular, it is difficult to perceive the locking state of a plurality of locking devices of a vehicle seat at the same time. 
     DE 10 2004 060 565 A1 discloses a locking device which has a locking indicator and an unlocking indicator for indicating the locking state of the locking device. 
     DE 10 2004 060 565 A1 also discloses a locking device which has a locking indicator and an unlocking indicator for indicating the locking state of the locking device. 
     SUMMARY OF THE INVENTION 
     An object of the invention is to improve a locking device for a vehicle seat of the type mentioned in the introduction, in particular, to increase the visibility of the indicator of the locking state of the locking device. 
     A locking device of the generic type for a vehicle seat comprises a display device for indicating the locking state of the locking device, wherein the display device has at least one locking indicator which is visible when the locking device is locked, and at least one unlocking indicator, which is visible when the locking device is unlocked. The display device has at least one indicator arm which is located in a locking position when the locking device is locked and which is located in an unlocking position when the locking device is unlocked. The indicator arm comprises a display region which has a first locking indicator and a first unlocking indicator. 
     According to the invention, there is provided on a metal retention sheet a second unlocking indicator which is covered by the indicator arm which is located in the locking position. 
     Both the locked locking state of the locking device and the unlocked locking state of the locking device can thereby be explicitly visually perceived in each case. The unlocked locking state of the locking device can be perceived at two different locations, that is to say, on the first unlocking indicator and on the second unlocking indicator. 
     In particular with the corresponding color identification, preferably by the at least one locking indicator being constructed as a surface which is provided with a green color, and/or by the at least one unlocking indicator being constructed as a surface which is provided with a red color, the visibility of the indication of the locking state of the locking device is advantageously increased. 
     Advantageously, the at least one locking indicator is covered when the locking device is unlocked. 
     The at least one unlocking indicator is also advantageously covered when the locking device is locked. 
     Preferably, the indicator arm is supported so as to be able to pivot from the locking position into the unlocking position thereof. 
     According to another advantageous embodiment of the invention, there is provided on the metal retention sheet a second locking indicator which is covered by the indicator arm which is located in the unlocking position. 
     Preferably, the second locking indicator and the second unlocking indicator are arranged at opposing sides of the metal retention sheet. 
     Advantageously, the first locking indicator is covered in this instance by the metal retention sheet when the indicator arm is located in the unlocking position. 
     Additionally or alternatively, the first unlocking indicator is also advantageously covered by the metal retention sheet when the indicator arm is located in the locking position. 
     Preferably, the first locking indicator and the first unlocking indicator are arranged at opposing sides of the display region. 
     According to an advantageous development of the invention, there is formed in the metal retention sheet a through-opening with which the display region is in alignment. 
     When the indicator arm is located in the locking position, it is located outside the through-opening. 
     When the indicator arm is located in the unlocking position, it protrudes through the through-opening. 
     In order to unlock the locking device, there is advantageously provided an unlocking lever which is coupled to the indicator arm so as to be carried therewith. 
     Preferably, the indicator arm and the unlocking lever can be pivoted about axes which extend in a parallel manner. 
     The object is also achieved by a vehicle seat which comprises at least one locking device according to the invention. 
     The present invention shall be explained in more detail on the basis of the following figures and exemplary embodiments, without the present invention being limited to these. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a longitudinal sectional view through a vehicle seat in the tumble position; 
         FIG. 2  is a side view of the vehicle seat from  FIG. 1  in the tumble position; 
         FIG. 3  is an enlarged illustration of the surrounded region of  FIG. 1  with the locking device locked; 
         FIG. 4  is an enlarged illustration of the surrounded region of  FIG. 1  with the locking device unlocked; 
         FIG. 5  is an enlarged illustration of the surrounded region of  FIG. 2  with the locking device locked; 
         FIG. 6  is an enlarged illustration of the surrounded region of  FIG. 2  with the locking device unlocked; and 
         FIG. 7  is a schematic illustration of a vehicle seat. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A vehicle seat  1  for a motor vehicle has a seat member  2  and a backrest  3  which is fitted thereto and which can be folded relative to the seat member  2 . A headrest  4  is arranged at the end of the backrest  3  facing away from the seat member  2 . 
     The arrangement of the vehicle seat  1  inside the vehicle and the conventional travel direction thereof define the directional indications used below. In this instance, a direction which is orientated perpendicularly relative to the ground is referred to below as the vertical direction and a direction perpendicular relative to the vertical direction and perpendicular relative to the travel direction is referred to below as the transverse direction. 
     The vehicle seat  1  can be secured to the vehicle structure by means of a plurality of locking devices  10 . In this instance, two locking devices  10  are provided in a rear region of the vehicle seat  1  in the travel direction, one of these locking devices  10  being arranged at the right-hand side in the travel direction and the other of these locking devices  10  being arranged at the left-hand side in the travel direction. Two additional locking devices  10  are provided in a front region of the vehicle seat  1  in the travel direction, one of these locking devices  10  being arranged at the right-hand side in the travel direction and the other of these locking devices  10  being arranged at the left-hand side in the travel direction. 
     The vehicle seat  1  described in this instance is a seat in a second seat row of a vehicle.  FIG. 1  is a section through the vehicle seat  1  perpendicularly relative to the transverse direction, the locking devices  10  which are arranged at the right-hand side in the travel direction being visible.  FIG. 2  is a side view of the vehicle seat  1 , the locking devices  10  which are arranged on the left in the travel direction being visible. 
       FIG. 3  and  FIG. 4  illustrate the locking device  10  which is arranged in the front region of the vehicle seat  1  on the right in the travel direction, and  FIG. 5  and  FIG. 6  illustrate the locking device  10  which is arranged in the front region of the vehicle seat  1  on the left in the travel direction. In all the illustrations shown in this instance, the viewing direction is the same, that is to say, in each case in the transverse direction, to the right in relation to the travel direction. 
     In the locked state, a detent  11  of the locking device  10  engages around a pin  15  which is arranged on the vehicle structure. In the unlocked state of the locking device  10 , the detent  11  is pivoted away about an axis which extends in the transverse direction and releases the pin  15 . For unlocking, an unlocking lever  16  which is secured to a securing element which is not illustrated is pivoted about an axis which extends in the transverse direction, whereby the securing element releases the detent  11 . Such a locking device  10  is described, for example, in WO 2004/069 585 A2, the disclosure content of which in this regard is explicitly incorporated herein by reference. 
     Based on a conventional travel position, the backrest  3  can be folded onto the seat member  2 . By subsequently unlocking the rear locking devices  10 , the rear region of the vehicle seat  1  can be pivoted upward and moved into a tumble position, as illustrated in  FIG. 1  and  FIG. 2 . A gas compression spring  5  retains the vehicle seat  1  in the tumble position. 
     By unlocking the two front locking devices  10 , which will be set out in greater detail below, in the tumble position the vehicle seat  1  can be released from the vehicle structure and removed from the vehicle. 
     The two front locking devices  10  are in this instance constructed in a mirror-symmetrical manner with respect to a plane which extends perpendicularly relative to the transverse direction. It is also conceivable to construct the two rear locking devices  10  in the same manner as the two front locking devices  10 . 
     The two front locking devices  10  each have a display device  8 , which indicates the locking state of the respective locking device  10 . The display device  8  consequently indicates whether the respective locking device  10  is locked or unlocked. 
     Each of the front locking devices  10  is secured to the vehicle seat  1  by means of a metal retention sheet  20 . An end of the gas compression spring  5  is also fitted to the metal retention sheet  20 . The metal retention sheet  20  extends primarily in the longitudinal direction and the vertical direction. 
     The metal retention sheet  20  comprises a retention region  22  which is located at the bottom in the vertical direction and to which the gas compression spring  5  is secured, and a functional region  24  which is located at the top in the vertical direction and which is offset relative to the retention region  22  in the transverse direction. A through-opening  26  is consequently formed between the functional region  24  and the retention region  22  when viewed in the vertical direction. 
     The display device  8  has an indicator arm  30  which is supported on the metal retention sheet  20  so as to be able to be pivoted about an axis which extends in a transverse direction. The axis about which the detent  11  can be pivoted, the axis about which the unlocking lever  16  can be pivoted and the axis about which the indicator arm  30  can be pivoted consequently extend parallel with each other in the transverse direction. 
     The indicator arm  30  and the unlocking lever  16  are coupled so as to be carried with each other, in this instance by means of a tenon and slot guide. At the end of the indicator arm  30  remote from the rotation axis thereof, there is provided a display region  39  which is in alignment with the through-opening  26  of the metal retention sheet  20  when viewed in the transverse direction. 
     When the locking device  10  is locked, as illustrated in  FIG. 3  and  FIG. 5 , the indicator arm  30  is located in the locking position, the display region  39  being located in a vertical direction substantially at the same height as the functional region  24  of the metal retention sheet  20  and above the through-opening  26 . The indicator arm  30  which is located in the locking position is consequently located outside the through-opening  26 . 
     When the locking device  10  is unlocked, as illustrated in  FIG. 4  and  FIG. 6 , the indicator arm  30  is in the unlocking position, the display region  39  being introduced into the through-opening  26  and being located in a vertical direction below the functional region  24  and substantially at the same height as the retention region  22  of the metal retention sheet  20 . The indicator arm  30  located in the unlocking position consequently extends through the through-opening  26 . 
     At the side facing inward in the transverse direction, that is to say, directed toward the center of the vehicle seat, the display region  39  has a first locking indicator  31  which can be seen in  FIG. 3 . At the side facing outward in the transverse direction, that is to say, directed away from the center of the vehicle seat, the display region  39  has a first unlocking indicator  33  which can be seen in  FIG. 6 . 
     At the side facing inward in the transverse direction, the functional region  24  has a second unlocking indicator  34 , which can be seen in  FIG. 4 . At the side facing outward in the transverse direction, the retention region  22  has a second locking indicator  32  which can be seen in  FIG. 5 . 
     The locking indicators  31 ,  32  are constructed in this instance as surfaces which are provided with a green color and indicate that the vehicle seat  1  is secured to the vehicle structure. The unlocking indicators  33 ,  34  are constructed in this instance as surfaces which are provided with a red color and indicate that the vehicle seat  1  can be released from the vehicle structure. 
     When the locking device  10  is locked and the indicator arm  30  is in the locking position, the first locking indicator  31  when viewed in the transverse direction from the inner side can consequently be seen in the display region  39  of the indicator arm  30 , as illustrated in  FIG. 3 , and, when viewed in the transverse direction from the outer side, the second locking indicator  32  can be seen in the retention region  22  of the metal retention sheet  20 , as illustrated in  FIG. 5 . The second unlocking indicator  34  is in this instance covered by the display region  39  of the indicator arm  30  and the first unlocking indicator  33  is in this instance covered by the functional region  24  of the metal retention sheet  20 . 
     When the locking device  10  is unlocked and the indicator arm  30  is in the unlocking position, the first unlocking indicator  33  when viewed in the transverse direction from the outer side can consequently be seen in the display region  39  of the indicator arm  30 , as illustrated in  FIG. 6  and, when viewed in the transverse direction from the inner side, the second unlocking indicator  34  in the functional region  24  of the metal retention sheet  20  can be seen, as illustrated in  FIG. 4 . The second locking indicator  32  is in this instance covered by the display region  39  of the indicator arm  30  and the first locking indicator  31  is in this instance covered by the retention region  22  of the metal retention sheet  20 . 
     The features disclosed in the above description, the claims and the drawings may be significant both individually and in combination in order to implement the invention in the various configurations thereof. 
     While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.