Patent Publication Number: US-2004047093-A1

Title: Control method of sliding a vehicle door by a powered sliding device

Description:
BACKGROUND OF THE INVENTION  
       [0001] 1. Field of the Invention  
       [0002] The present invention relates to a control method of sliding a vehicle door by a powered sliding device, and particularly, relates to the quality control for improving the operating feeling at the time of the finish of the opening sliding movement of the door.  
       [0003] 2. Description of the Related Art  
       [0004] Conventionally, a powered sliding device for a vehicle sliding door has been well known, wherein the sliding door is slid in the door closing direction and in the door opening direction by rotating a wire drum connected through a wire cable to the sliding door by the power of a motor, and the sliding door moved to the door-open position by the sliding device is kept at the door-open position by a door holder.  
       [0005] In the door holders, there are a mechanical engaging type holder which uses a latch/ratchet mechanism and a striker, and an overcoming type holder which uses an elastic projecting strip such as a plate spring or an inelastic projecting strip. The overcoming type holder is provided at a proper position of the vehicle body, and keeps the door at the door-open position by coming into contact with part of the door. Here, as shown in FIG. 5, the door-open position means a position between the mechanical door-open end DOE which is the moving limit of the door and the position MRP where the door receives the maximum overcoming resistance from the door holder, and generally, it has a width of about 20 to 40 mm.  
       [0006] The sliding door positioned at the door-open position is detected by a holder switch. The holder switch detects whether the sliding door is positioned at the door-open position or the sliding door is not positioned at the door-open position. However, it is very difficult to accurately set the on/off switching position (holder check point HCP) of the holder switch at the maximum resistance position MRP of the door holder, and therefore, generally, the holder check point HCP is set on the door closing side of the maximum resistance position MRP.  
       [0007] The holder check point HCP is also used as the reference point of decelerating the sliding speed of the door, and it is arranged that when the sliding door passes the holder check point HCP by the opening sliding movement, the sliding door is decelerated, and runs into the door-open end DOE at a slow speed.  
       [0008] If the speed is fast when the sliding door runs into the vehicle body at the door-open end DOE, a good operating feeling of the sliding door cannot be obtained, and furthermore, the durability of the sliding door is lowered. However, if the timing of decelerating the sliding speed is early, it takes a long time to finish the sliding movement.  
       SUMMARY OF THE INVENTION  
       [0009] Therefore, it is an object of the present invention to provide a quality control by which it is possible to accurately set the final decelerating position of the sliding door on the door opening side of the maximum resistance position MRP of the door holder.  
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0010]FIG. 1 is a side view of a vehicle with a powered sliding device and a sliding door;  
     [0011]FIG. 2 is an expansion plan of the sliding device and the sliding door;  
     [0012]FIG. 3 is a block diagram for performing the control operation of the present invention;  
     [0013]FIG. 4 is an explanation figure showing the relation of a plurality of setting positions set near the door-open position of the sliding door; and  
     [0014]FIG. 5 is a figure of a well known example showing the relation of a plurality of setting positions set near the door-open position of the sliding door. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0015] One preferred embodiment of the present invention will be described by using drawings. FIG. 1 shows the schematic relation between a powered sliding device  10  according to the present invention and a vehicle sliding door  11  which is slidable in the door closing direction and in the door opening direction by the powered sliding device  10 , and FIG. 2 shows the expanded relation of both.  
     [0016] The sliding door  11  is slidably attached to a vehicle body  12 , and slides in the back and forth direction of the vehicle body  12  along a guide rail  13  provided to the vehicle body  12 . The sliding device  10  has a motor  14 , a reduction mechanism  15 , a wire drum  16 , and an auxiliary brake  17 , and these are attached to a base plate  18  fixed to the vehicle body  12 . The auxiliary brake  17  has electrical control parts such as a solenoid, and when operating, it gives rotational resistance to the wire drum  16 . The rotational shaft  17 A of the auxiliary brake  17  rotates together with the rotation of the wire drum  16  when the auxiliary brake  17  is not operated.  
     [0017] To the wire drum  16 , one end sides of two wire cables  19 ,  20  are connected. The other end side of the first cable  19  is connected to a bracket  22  of the sliding door  11  through a front pulley  21  pivoted to the vehicle body  12 . Similarly, the other end side of the second cable  20  is connected to the bracket  22  of the sliding door  11  through a rear pulley  23  pivoted to the vehicle body  12 .  
     [0018] To the base plate  18 , a tension case  24  having a tension spring in the interior (not shown) is fixed by a screw or the like. The wire cables  19 ,  20  extending from the wire drum  16  pass in the tension case  24  to be connected to the sliding door  11 , and a specified tension is applied by the tension spring.  
     [0019] Between the reduction mechanism  15  and the wire drum  16 , a clutch mechanism  25  is provided, and the rotation of the motor  14  is transferred to the wire drum  16  through the reduction mechanism  15  and the clutch mechanism  25 . The structure of the clutch mechanism  25  is free. For example, an electromagnetic clutch which can be switched to the connected state and the disconnected state between the motor  14  and the wire drum  16  by the operation of an electromagnet, or a clutch which is switched to the connected state when the motor  14  rotates and switched to the disconnected state when the motor  14  stops, or a clutch which is switched to the connected state by the rotation of the motor  14  but which can keep the connected state even when the motor  14  is stopped (refer to U.S. Pat. No. 6,359,762), or the like can be used.  
     [0020] When the wire drum  16  rotates clockwise by the power of the motor  14 , the first wire cable  19  is wound up, and at the same time, the second wire cable  20  is pulled out, and the sliding door  11  slides in the door closing direction, and by the counterclockwise rotation of the wire drum  16 , the second wire cable  20  is wound up, and at the same time, the first wire cable  19  is pulled out, and the sliding door  11  slides in the door opening direction.  
     [0021] As shown in FIG. 1, to the guide rail  13  of the vehicle body  12 , a door holder  26  for holding the sliding door  11  at the door-open position is attached. The door holder  26  of the present embodiment is an overcoming holding type holder having an elastic projecting strip made of a bending plate spring or an elastic rubber, or an inelastic mere projecting strip. When the sliding door  11  moves in the door opening direction, the door  11  passes the holder check point HCP, as shown in FIG. 4, and the door  11  then gets over the maximum resistance position MRP of the door holder  26 , and after that, the door runs into a door stopper  27  fixed to the vehicle body at the door-open end DOE which is the limit position where mechanical sliding in the door opening direction is possible, and the door opening finishes. The door-open position means the position between the maximum resistance position MRP of the door holder  26  and the door-open end DOE, and generally, it has a width X of about 20 to 40 mm. The overcoming resistance of the door holder  26  is shaped like a mountain, as shown in FIG. 4.  
     [0022] In FIG. 2, to a drum shaft  16 A of the wire drum  16 , a cam disk  28  is supported. The cam disk  28  is set to perform one rotation when the wire drum  16  performs three to four rotations. The three to four rotations of the wire drum  16  is equal to the moving quantity of the whole stroke of the sliding door  11 , and accordingly, when the sliding door  11  moves from the door-open position to the door-closed position and vice versa, the cam disk  28  performs just one rotation. Close to the cam disk  28  from outside, a holder switch  29  which is switched from ON to OFF by the contact with the cam disk  28  is provided. The switching point of on/off of the holder switch  29  is the holder check point HCP. The holder check point HCP is set on the door closing side of the maximum resistance position MRP of the door holder  26 , and the distance Y between the holder check point HCP and the door-open end DOE is longer than the width X. The holder check point HCP is set by the holder switch  29  provided in the interior of the powered sliding device  10 , and therefore, the position of the holder check point HCP is fluctuated by the dispersion of the mounting position of the holder switch  29  or the change of the length of the wire cables  19 ,  20  because of the aged deterioration or the like, and the distance Y is also fluctuated.  
     [0023] In FIG. 2, to the rotational shaft  17 A, a slit disk  30  is supported. The slit disk  30  rotates together with the wire drum  16 . The slits of the slit disk  30  are detected by a photo sensor  31 . The sliding quantity (sliding position) of the sliding door  11  is found by measuring the rotational quantity of the slit disk  30  by the photo sensor  31 , and the sliding speed of the sliding door  11  is found by measuring the rotational speed of the slit disk  30 , and the sliding direction of the sliding door  11  is found by measuring the rotating direction of the slit disk  30 .  
     [0024] In FIG. 4, on the door opening side of the maximum resistance position MRP of the door holder  26 , the opening speed final decelerating position FDP which is the essential point of the present invention is set. The distance Z between the door-open end DOE and the final decelerating position FDP is shorter than the width X, and about 10 mm is preferable.  
     [0025]FIG. 3 is a block diagram for performing the control operation according to the present invention. The block diagram has a controller  32 , an ammeter (motor load detector)  33  for measuring the current flowing in the motor  14 , a battery  34 , an operating switch  35 , and a transformation circuit  36 .  
     OPERATION  
     [0026] When the operating switch  35  is operated to the door opening side, the door opening operation of the sliding control is performed by the controller  32 , and by the motor  14 , the wire drum  16  is rotated in the door opening direction, and the sliding door  11  starts to slide in the door opening direction.  
     [0027] When the cam disk  28  is rotated by the continuing of the opening sliding movement of the door and the holder switch  29  is switched from on to off, the controller  32  can detects the passing through the holder check point HCP of the sliding door  11 , and consequently, the controller  32  starts the integration of the pulse signals from the photo sensor  31 . Then, the sliding door  11  slides in the door opening direction as it is, the sliding door  11  gets over the door holder  26 , and runs into the door stopper  27  at the door-open end DOE. when the sliding door  11  runs into the door stopper  27 , the sliding quantity of the sliding door  11  from the holder check point HCP to the door-open end DOE is found from the number of pulse signals from the holder check point HCP to the door-open end DOE, and the distance Y from the holder check point HCP to the door-open end DOE is found.  
     [0028] Next, the controller  32  calculates the proper value of the distance Z′ from the holder check point HCP to the final decelerating position FDP on the basis of the relation between the actually measured distance Y and the specified distance Z between the door-open end DOE and the final decelerating position FDP. The found proper value of the distance Z′ is used in the next door opening operation.  
     [0029] When the next door opening operation is performed and the sliding door  11  passes through the holder check point HCP, the controller  32  starts the integration of the pulse signals from the photo sensor  31 . Then, if the integrated pulse signals become equal to the proper distance Z′, the controller  32  judges that the sliding door  11  has reached the opening speed final decelerating position FDP, and decelerates the sliding door  11  by lowering the supply voltage to the motor  14  by the transformation circuit  36 . Accordingly, the sliding door  11  is surely decelerated at the final decelerating position FDP separated from the door-open end DOE by the distance Z, and it can come into contact with the door stopper  27  at the door-open end DOE at a slow speed.  
     [0030] It is preferable to measure the distance Y from the holder check point HCP to the door-open end DOE each time the door opening operation is performed, and according to that result, the data of the distance Z′ should be renewed successively. Thus, by renewing the distance Z′, the effects of the dispersion of the mounting position of the holder check point HCP or the change of the length of the wire cables  19 ,  20  are removed, and the final decelerating position FDP can accurately be set.  
     [0031] It is preferable to store a temporary value of the distance Z′ between the holder check point HCP and the opening speed final decelerating position FDP in advance in the controller  32 . The temporary value of the distance Z′ prevents the strong collision between the sliding door  11  and the door stopper  27  in the first door opening operation.  
     [0032] The decelerating ratio of the sliding door  11  performed in the final decelerating position FDP is a design item to be determined by the factor such as the magnitude of the load of the motor  14 .  
     [0033] The deceleration at the final decelerating position FDP is the final deceleration for preventing the strong collision between the sliding door  11  and the door stopper  27 . Accordingly, it is also possible to apply the first order deceleration to the sliding door  11  on the basis of the holder check point HCP.  
     ADVANTAGE  
     [0034] In the present invention, the opening speed final decelerating position FDP can accurately be set near the door-opening end DOE on the door opening side of the maximum resistance position MRP of the door holder  26 , and therefore, it is possible to reduce the time necessary for the finish of the door opening while reducing the shock when the sliding door  11  comes into contact with the door stopper  27 .