Abstract:
A control apparatus for opening and closing a convertible top of a vehicle includes first detecting device for outputting a first signal representing that a movable roof is closed, a second detecting device for outputting a second signal representing that a locking mechanism is in a locked condition, a third detecting device for outputting a third signal representing that a driving mechanism is turned to an excessive load condition, and a controller for controlling the driving mechanism according to the first signal, the second signal and the third signal. The controller includes a processing device for executing an error step when the third signal is inputted to the controller and the second signal is not inputted to the controller while the first signal is inputted to the controller.

Description:
This application is based on and claims priority under 35 U.S.C. § 119 with respect to Japanese Application No. 2000-049437 filed on Feb. 25, 2000, the entire content of which is incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The present invention generally relates to a convertible top of a vehicle. More particularly, the present invention pertains to a control apparatus for opening and closing a vehicle convertible top having a locking mechanism which is arranged between a movable roof and a vehicle body as well as a driving mechanism which is coupled to the locking mechanism to drive the locking mechanism in a locked condition and an unlocked condition. 
     BACKGROUND OF THE INVENTION 
     An example of a known control apparatus for opening and closing a convertible top of a vehicle is disclosed in U.S. Pat. No. 4,749,193. The convertible top includes a locking mechanism and a driving mechanism. The locking mechanism is arranged between a movable roof and a vehicle body to hold the movable roof of the vehicle body in a fully closed position. The driving mechanism is coupled to the locking mechanism to drive the locking mechanism between a locked condition and an unlocked condition. The control apparatus also includes a limit switch, a position sensor and a control unit. The limit switch outputs a first signal indicating that the movable roof is closed. The position sensor outputs a second signal indicating that the locking mechanism is in the locked condition. The control unit controls the driving mechanism according to the first signal and the second signal. The control unit effects the driving operation of the driving mechanism when the first signal is inputted to the control unit from the limit switch. Further, the control unit stops the operation of the driving mechanism when the second signal is inputted to the control unit from the position sensor. Therefore, the locking mechanism is turned to the locked condition from the unlocked condition when a signal inputted to the control unit is switched from the first signal to the second signal. 
     In the above mentioned known control apparatus, while the limit switch outputs the first signal, the movable roof may not always be at the fully closed position because the position of the movable roof is not always stable at the fully closed position by virtue of the construction of the movable roof relative to the vehicle body. Therefore, the locking mechanism may fail to switch to the locked condition from the unlocked condition. That is, the locking mechanism may not be in the locked condition even though the second signal is outputted to the control unit from the position sensor. 
     A need thus exists for an improved vehicle convertible top control apparatus that is able to address at least the drawbacks noted above. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, a control apparatus adapted to open and close a convertible top of a vehicle includes first detecting device for outputting a first signal representing that a movable roof of the vehicle is closed, a second detecting device for outputting a second signal representing that a locking mechanism is in a locked condition, a third detecting device for outputting a third signal representing that a driving mechanism is turned to an excessive load condition, and a control device for controlling the driving mechanism according to the first signal, the second signal and the third signal. The control device has a processing mechanism for executing an error step when the third signal is inputted to the control device and the second signal is not inputted to the control device while the first signal is inputted to the control device. 
     Another aspect of the invention involves a control apparatus for opening and closing a convertible top of a vehicle which includes a locking mechanism arranged between a movable roof and a vehicle body for holding the movable roof in a closed position and a motor operatively connected to the locking mechanism to drive the locking mechanism between a locked condition and an unlocked condition upon supply of electric current. The control apparatus includes a closed condition detection switch that detects the closed position of the movable roof and outputs a signal upon detection of the closed position of the movable roof, a locked condition detection switch that detects the locked condition of the locking mechanism and outputs a signal upon detection of the locked condition of the locking mechanism, an excessive electric current detection circuit that detects excessive electric current supplied to the motor and outputs a signal upon detection of excessive electric current supplied to the motor, and a controller that receives the signals outputted from the closed condition detection switch, the locked condition detection switch and the excessive electric current detection circuit to stop operation of the motor when the controller, upon receiving the signal from the excessive electric current detection circuit after receiving the signal from the closed condition detection switch, does not receive the signal from the locked condition detection switch. 
     Another aspect of the invention involves a method for detecting an error associated with operation of a convertible top of a vehicle that includes a locking mechanism arranged between a movable roof and a vehicle body for holding the movable roof in a closed position and a driving mechanism operatively connected to the locking mechanism to drive the locking mechanism between a locked condition and an unlocked condition. The method includes detecting that the movable roof has reached a fully closed position, detecting an excessive load condition of the driving mechanism while the driving mechanism is driving the locking mechanism towards the locked condition, and determining the occurrence of an error upon detecting the excessive load condition of the driving mechanism after detecting that the movable roof has reached the fully closed position and in the absence of a detection that the locking mechanism has reached the locked condition. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING FIGURES 
     The foregoing and additional features and characteristics of the present invention will become more apparent from the following detailed description considered with reference to the accompanying drawing figures in which like reference numerals designate like elements and wherein: 
     FIG. 1 is a schematic diagram of the vehicle convertible top controller according to the present invention; 
     FIG. 2 is a front view of a locking mechanism used in the vehicle convertible top according to the present invention; 
     FIG. 3 is a perspective view of the vehicle convertible top according to the present invention; and 
     FIG. 4 is a timing chart of the controller according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A control apparatus for opening and closing a convertible top of a vehicle in accordance with the present invention is described below with reference to FIGS. 1-4. Referring initially to FIG. 3, a convertible top  2  of a vehicle  1  includes a movable roof panel  21  and a movable back panel  22 . The convertible top  2  is movably supported on a rear fender panel  11  of the vehicle  1  by a pair of roof link mechanisms (not shown) so that the convertible top  2  is moved between an opened condition and a closed condition (as shown in FIG.  3 ). When the convertible top  2  is in the opened condition, the convertible top  2  is accommodated under a trunk lid  13  of a rear portion of the vehicle  1 . When the convertible top  2  is in the closed condition, the movable roof panel  21  is positioned at a fully closed position A shown in FIG. 2 so that the front end portion  21   a  of the movable roof panel  21  is held at a front roof pillar  12  of the vehicle  1 . The roof link mechanisms are coupled to electric motors  3 ,  4  generally shown in FIG.  1 . The drive force generated by the electric motors  3 ,  4  is transmitted to the roof link mechanisms so that the roof link mechanisms cause the convertible top  2  to move between the opened condition and the closed condition. 
     As shown in FIG. 3, a pair of locking mechanisms  5 ,  5  is arranged between the front end portion  21   a  of the movable roof panel  21  and the front roof pillar  12  of the vehicle  1 . The locking mechanisms  5 ,  5  are coupled to an electric motor  6  that drives the locking mechanisms  5 ,  5 . Upon operation, the locking mechanisms  5 ,  5  turn between a locked condition and an unlocked condition. 
     As shown in FIG. 2, the locking mechanisms  5 ,  5  include a hook  51 , an engaging pin  52 , a load receiving pin  57  and a receiving member  58 . The hook  51  is movably supported on a base bracket  53  by a pair of links  54 ,  55 . The base bracket  53  is attached on the front end portion  21   a  of the movable roof panel  21 . The link  54  is rotatably supported on the base bracket  53  by a pin  54   a . One end of the link  55  is rotatably supported on the base bracket  53  by a pin  55   a . The hook  51  is rotatably supported on the link  54  by a pin  54   b  and is rotatably supported on opposite end of the link  55  by a pin  55   b . An engaging groove  51   a  is formed on the side of the hook  51 . The link  55  is connected to the electric motor  6  via a rod  61 . The drive force generated by the electric motor  6  is transmitted to the hook  51  through the rod  61  and the link  54 . Therefore, the hook  51  moves to be turned between a fully locked position B in which the locking mechanism  5  is in the locked condition and a fully unlocked position C in which the locking mechanism  5  is in the unlocked condition. While the hook  51  moves, the engaging groove  51   a  of the hook  51  is moved on an arc locus F around the pin  55   a  by the link  55 . An integral contacting portion  51   b  of the hook  51  is formed on the hook  51  with the engaging portion  51   a.    
     The engaging pin  52  is fixed on a base bracket  56 . The base bracket  56  is attached on the front roof pillar  12  of the vehicle  1  so as to be positioned opposite the engaging groove  51   a . When the engaging pin  52  is positioned on the arc locus F of the engaging groove  51   a  and the movable roof panel  21  is positioned at the fully closed position A, the engaging pin  52  is engageable with and disengageable from the engaging groove  51   a . When the engaging pin  52  is not positioned on the arc locus F of the engaging groove  51   a  and the movable roof panel  21  is not positioned at the fully closed position A, the engaging pin  52  is not able to be engageable with and disengageable from the engaging portion  51   a  and contactable with the contacting portion  51   b  of the hook  51 . When the hook  51  is positioned in the fully locked position B, the engaging pin  52  is engaged with the engaging groove  51   a  and the link  54  contacts a stopper portion  53   a  formed on the base bracket  53 . When the hook  51  is positioned in the fully unlocked position C, the engaging pin  52  is disengaged from the engaging groove  51   a  and the link  54  is contacted to a stopper portion  53   b  formed on the base bracket  53 . 
     The load receiving pin  57  is fixed on the base bracket  53 . The receiving member  58  is fixed on the base bracket  56  in opposition to the load receiving pin  57 . When the movable roof panel  21  of the convertible top  2  is positioned at the fully closed position A, the load receiving pin  57  is fitted into the receiving member  58 . Therefore, the force loading the movable roof panel  21  is transmitted to the front roof pillar  12  of the vehicle  1  via the load receiving pin  57  and the receiving member  58 . 
     As shown in FIG. 1, a controller  7  for controlling operation of the vehicle convertible top includes a central processing unit (CPU)  71 , a motor drive circuit  72 , a power supply circuit  73 , an input circuit  74 , an excessive electric current detection circuit  75  and an output circuit  76 . The CPU  71  is a micro processor. The electric motors  3 ,  4 ,  6  are electrically connected to an output port of the CPU  71  through the motor drive circuit  72 . A pair of closed condition detection switches  62 ,  62 , a locked condition detection switch  64  and an operation switch  8  are electrically connected to an input port of the CPU  71  through the input circuit  74 . An alarm  10  is electrically connected to an output port of the CPU  71  through the output circuit  76 . A battery  9  of the vehicle  1  is electrically connected to the power supply circuit  73 . The power supply circuit  73  is electrically connected to the CPU  71 , the motor drive circuit  72 , the power supply circuit  73 , the input circuit  74  and the output circuit  76  to supply electric power to the CPU  71  and the circuits  72 ,  73 ,  74  and  76 . 
     The excessive electric current detection circuit  75  is electrically disposed between the motor drive circuit  72  and the power supply circuit  73 . The excessive electric current detection circuit  75  monitors the electric current supplied to the electric motors  3 ,  4 ,  6  through the motor drive circuit  72 . The excessive electric current detection circuit  75  is also electrically connected to the CPU  71 . When the value of the electric current supplied to the electric motors  3 ,  4 ,  6  exceeds a predetermined value, the excessive electric current detection circuit  75  outputs an excessive load signal to the CPU  71 . 
     As shown in FIG. 2, the locked condition detection switch  64  is fixed on the base bracket  53  of one of the locking mechanisms  5 . A movable contact  64   a  of the locked condition detection switch  64  is arranged for contacting engagement with a contact arm  54   c  of the link  54 . The movable contact  64   a  of the locked condition detection switch  64  contacts the contact arm  54   c  of the link  54  when the hook  51  is positioned at a predetermined position between the fully locked position B and the fully unlocked position C of the hook  51 . The locked condition detection switch  64  outputs an ON signal to the CPU  71  through the input circuit  74  when the movable contact  64   a  contacts the contact arm  54   c  of the link  54 . 
     The closed condition detection switches  62 ,  62  are fixed on the base bracket  56  of both locking mechanisms  5 ,  5 . A movable contact  62   a  of the closed condition detection switch  62  is arranged for contacting engagement with the load receiving pin  57 . The movable contact  62   a  contacts the load receiving pin  57  when the movable panel  21  is positioned at a predetermined position arranged on the open side relative to the fully closed position A. The closed condition detection switch  62  outputs an ON signal to the CPU  71  through the input circuit  74  when the movable contact  62   a  contacts the receiving pin  57 . 
     As shown in FIGS. 1,  2 ,  3  and  4 , while the movable roof  2  moves toward the closed direction D (as shown in FIG. 3) by the operation of the electric motors  3 ,  4 , the receiving pin  57  fits into or is received in the receiving member  58  and the front end portion  21   a  of the movable roof panel  21  contacts the front roof pillar  12  of the vehicle  1 . The receiving pin  57  contacts the movable contact  62   a  of the closed condition detection switch  62  and the electric current supplied to the electric motor  3 ,  4  exceeds the predetermined value by contact between the front roof pillar  12  and the front end portion  21   a  of the movable roof panel  21 . Therefore, the closed condition detection switch  62  outputs the ON signal to the CPU  71  and the excessive electric current detection circuit  75  outputs the load excessive signal to the CPU  71 . 
     When the ON signal outputted by the closed condition detection switches  62  and the load excessive signal outputted by the excessive electric current detection circuit  75  are inputted to the CPU  71 , the CPU  71  outputs a stop signal to the motor drive circuit  72 . Therefore, the operation of the electric motors  3 ,  4  is stopped. As a result, the movable roof panel  21  is positioned at the fully closed position A. The CPU  71  outputs a drive signal to the motor drive circuit  72  when a predetermined time is passed after the output of the stopped signal. Therefore, the electric motor  6  is operated or driven. 
     The operation of the motor  6  causes the hook  51  to move toward a lock direction E as shown in FIG. 2 from the unlocked position C. The contact arm  54   c  contacts the movable contact  64   a  of the switch  64  and the link  54  contacts the stopper portion  53   a  of the base bracket  53 . The electric current supplied to the electric motor  6  exceeds the predetermined value by virtue of the contact between the stopper portion  53   a  and the link  54 . Therefore, the locked condition detection switch  64  outputs the ON signal to the CPU  71  and the excessive electric current detection circuit  75  outputs the load excessive signal to the CPU  71 . When the ON signal from the locked condition detection switch  64  and the load excessive signal from the excessive electric current detection circuit  75  are inputted to the CPU  71 , the CPU  71  outputs a stop signal to the motor drive circuit  72 . Therefore, the operation of the electric motor  6  is stopped. As a result, the hook  51  is positioned at the fully locked position B. 
     When the engaging pin  52  is positioned on the arc locus F of the engaging groove  51   a  of the hook  51  while the hook  51  moves toward the lock direction E (as shown in FIG. 2) by the operation of the electric motor  6 , the engaging pin  52  is engaged with the engaging groove  51   a  of the hook  51 . Therefore, the movable roof panel  21  is held against the front roof pillar  12  by the locking mechanisms  5 ,  5 . When the engaging pin  52  is not positioned on the arc locus F of the engaging groove  51   a  of the hook  51  while the hook  51  moves toward the lock direction E (as shown in FIG. 2) by the operation of the electric motor  6 , the engaging pin  52  contacts the contacting portion  51   b  of the hook  51 . The contact arm  54   c  of the link  54  does not contact the movable contact  64   a  of the locked condition detection switch  64  and the electric current supplied to the electric motor  6  exceeds the predetermined value by contact between the engaging pin  52  and the contacting portion  51   b  of the hook  51 . Therefore, the locked condition detection switch  64  does not output the ON signal to the CPU  71  and the excessive electric current detect circuit  75  outputs the load excessive signal to the CPU  71 . 
     The error step is executed by the CPU  71  in the following manner. When the ON signal outputted by the locked condition detection switch  64  is not inputted to the CPU  71  and the load excessive signal outputted by the excessive electric current detection circuit  75  is inputted to the CPU  71 , the CPU  71  outputs an error signal to the output circuit  76  and a stop signal to the motor drive circuit  72 . Therefore, the alarm  10  warns the user of the vehicle  1  and the electric motor  6  is stopped. While the hook  51  moves toward the lock direction E (as shown in FIG. 2) by the electric motor  6 , although the closed condition detection switch  62  outputs the ON signal to the CPU  71 , the CPU  71  outputs the error signal to the output circuit  76 . 
     In accordance with the present invention, it is possible to substitute a torque and/or revolution sensor for detecting the torque and/or revolution of the electric motors  3 ,  4 ,  6  for the excessive electric current detection circuit  75 . 
     The principles, preferred embodiment and mode of operation of the present invention have been described in the foregoing specification. However, the invention which is intended to be protected is not to be construed as limited to the particular embodiment disclosed. Further, the embodiment described herein is to be regarded as illustrative rather than restrictive. Variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such variations, changes and equivalents which fall within the spirit and scope of the present invention as defined in the claims, be embraced thereby.