Vehicle door lock apparatus
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a door lock apparatus, and more particularly to a door lock apparatus for a vehicle. 
     2. Description of the Related Art 
     A conventional vehicle door lock apparatus is disclosed in Japanese Patent Laid Open Publication No. 2(1990)-221578. The vehicle door lock apparatus disclosed in this document comprises a base member fixed to a door at one side thereof and having a latch mechanism stored therein. The vehicle door lock apparatus further comprises a case member mounted on the other side of the base member and an actuator surrounded by the base member and the case member. 
     However, in accordance with this type of door lock apparatus, since the case member is mounted on the side of the base member opposite the attachment side of the base member to the door, a seam portion of the base member and the case member is exposed to an inside of the door. Therefore, rainwater is likely to flow into the portion of the vehicle door lock apparatus in which the actuator is disposed through the seam portion of the base member and the case member. 
     SUMMARY OF THE PRESENT INVENTION 
     It is an object of the present invention to provide a vehicle door lock apparatus which can prevent rainwater from flowing into a portion of the apparatus in which an actuator is disposed. 
     It is another object of the present invention to provide a vehicle door lock apparatus which can be conveniently manufactured. 
     It is a further object of the present invention to provide a vehicle door lock apparatus which is durable. 
     It is a further object of the present invention to provide a vehicle door lock apparatus which is simple in structure and small in size. 
     It is a further object of the present invention to provide a vehicle door lock apparatus which is low in cost. 
     To achieve the above mentioned objects, a vehicle door lock apparatus in accordance with the present invention comprises a body adapted to be fixed to a mounting portion of a door, a latch mechanism disposed in the body, a case adapted to be disposed between the mounting portion of the door and the body, and an actuating mechanism surrounded by the body and the case. The case is joined with a fixed side of the body which faces or is opposite to the mounting portion of the door. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The features and advantages of the vehicle door lock apparatus according to the present invention will become more apparent and will be more clearly appreciated from the following description considered in conjunction with the accompanying drawings in which like elements bear like reference numerals and wherein: 
     FIG. 1 is a plan view of a vehicle door lock apparatus of the present invention; 
     FIG. 2 is a rear elevational view of a vehicle door lock apparatus of the present invention; 
     FIG. 3 is a side elevational view of a vehicle door lock apparatus of the present invention; 
     FIG. 4 is a bottom view of a vehicle door lock apparatus of the present invention; 
     FIG. 5 is a sectional view of a vehicle door lock apparatus of the present invention taken on section line V--V of FIG. 2; 
     FIG. 6 is a sectional view of a vehicle door lock apparatus of the present invention taken on section line VI--VI of FIG. 2; 
     FIG. 7 is a sectional view of a vehicle door lock apparatus of the present invention taken on section line VII--VII of FIG. 2; 
     FIG. 8 is a sectional view of a vehicle door lock apparatus of the present invention taken on section line VIII--VIII of FIG. 2; and 
     FIG. 9 is a side view of a vehicle door lock apparatus of the present invention showing a mounting condition of a vehicle door lock apparatus on a vehicle door. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION 
     Referring to FIGS. 1 and 2, a body 1 which is made of a synthetic resin includes a first concave portion 2 and a second concave portion 3 on a rear side 1a. The rear side 1a constitutes a fixed side of the body that is fixed or secured to the mounting portion of the vehicle door. The first concave portion 2 is closed by a plate 4 which is made of a metallic material. A latch mechanism 5 which is formed with a pole 5a and a latch 5b is disposed in the first concave portion 2. On the other hand, the second concave portion 3 is closed by a case 6 which is made of a synthetic resin. An actuating mechanism 7 is disposed in the second concave portion 3. The actuating mechanism 7 is comprised of an electric motor 7a, a worm gear 7b, a wheel gear 7c and an output lever 7d. Furthermore, a link mechanism 8 is disposed on a front side 1b of the body 1. The link mechanism 8 is comprised of a lift lever 8a, an opening lever 8b and a locking lever 8c. 
     The pole 5a and the latch 5b of the latch mechanism 5 are rotatably supported on the body 1. The latch 5b is engagable and disengagable with a striker 5c (shown in FIG. 9) of a vehicle body 15 and the pole 5a is engagable and disengagable with the latch 5b. 
     The electric motor 7a of the actuating mechanism 7 is fixed to the case 6, and the wheel gear 7c and the output lever 7d are rotatably supported on the body 1. The worm gear 7b is secured on an output shaft of the electric motor 7a and is adapted to be engaged with the wheel gear 7c. Further, an output lever 7d is provided for being engagable with the wheel gear 7c. 
     The lift lever 8a of the link mechanism 8 is rotatably supported on the body 1 and is connected with the pole 5a. The locking lever 8c is secured with a supporting shaft of the output lever 7d which passes through the body 1 in order to be rotated with the output lever 7d. Further, the opening lever 8b is swingably and slidably supported on the body 1 through a link 8d. The opening lever 8b is connected with the locking lever 8c and is engagable and disengagable with the lift lever 8a. The plate 4 is fixed on the rear side 1a of the body 1 with a bolt 9. 
     As shown in FIG. 1 and FIGS. 5-8, the case 6 is fixed on the rear side 1a of the body 1 with a plurality of screws 11. A seal member 10 is interposed between the case 6 and the rear side 1a. Further, as seen in FIGS. 3-8, the body 1 includes a flange portion 12, which extends toward the case 6, on a side portion 1c of the body 1. A side seam portion 14 of the body 1 and the case 6 can be covered with the flange portion 12. The side seam portion 14 of the body 1 is formed at the juncture between the body 1 and the case at the left and right sides of the body which are the sides on the right and left of the body as seen with respect to the view shown in FIG. 2. 
     As shown in FIGS. 3 and 9, the vehicle door lock apparatus of the invention is mounted on a vehicle door 13 which is swingably supported on the vehicle body 15 in order to locate the first concave portion 2 on an upper portion of the vehicle door 13 and the second concave portion 3 on a lower portion of the vehicle door 13. The rear side 1a of the body 1 of the vehicle door lock apparatus is secured on a mounting portion 13a of the vehicle door 13 with, for instance, a plurality of bolts (not specifically shown in the figures) in order to dispose the case 6 between the body 1 and the mounting portion 13a. Therefore, a rear seam portion 16 of the body and the case 6 can be covered with the body 1 and the mounting portion 13a. The rear seam portion 16 is located at the juncture between the body 1 and the case 6 at the upper side of the second concave portion 3 as seen in FIG. 2. The striker 5c for engaging and disengaging the latch 5b is fixed on a portion of the vehicle body 15 which is opposite to the mounting portion 13a of the vehicle door 13. 
     The operation of the vehicle door lock apparatus will now be described. When each of the striker 5c and the pole 5a is engaged with the latch 5b in order to prevent the latch 5b from rotating (the Latch Condition of the apparatus) and the opening lever 8b and the lift lever 8a are able to be engaged with each other (the Unlock Condition of the apparatus), the vehicle door 13 is supported on the vehicle body 15 so that the vehicle door 13 is closed. At this time, if an outside handle (not shown in the figures) which is connected with the opening lever 8b is operated, the opening lever 8b moves linearly and engages the lift lever 8a so as to rotate the lift lever 8a. With rotation of the lift lever 8a, the pole 5a is also rotated and disengaged with the latch 5b (the Unlatch Condition of the apparatus) so as to permit vehicle door 13 to be opened. 
     On the other hand, when the electric motor 7a is operated, the wheel gear 7c is rotated through the worm gear 7b. Therefore, the wheel gear 7c is engaged with the output lever 7d and the output lever 7d is also rotated. The rotation of the output lever 7d causes rotation of the locking lever 8c and the opening lever 8b is swung. Consequently, the opening lever 8b and the lift lever 8a are not engagable with each other (the Lock Condition of the apparatus). 
     Under the Lock Condition, though the outside handle is operated, the vehicle door lock apparatus is not changed into the Unlatch Condition. Further, an inside handle (not shown in the figures) arranged on the interior side of the door 13 is connected with the lift lever 8a for establishing the Latch Condition and the Unlatch Condition of the door lock apparatus. Likewise, an outside handle (not shown) arranged at the exterior of the door is provided for establishing the Latch Condition and the Unlatch Condition of the door lock apparatus. A key cylinder (not shown in the figures) is connected with the locking lever 8c in order to selectively change the vehicle door lock apparatus between the Lock Condition and the Unlock Condition. The motor 7a is operated by a switch (not shown) located at the interior side of the door 13 for selectively changing between the Lock Condition and the Unlock Condition. 
     In accordance with the invention, the case 6 is disposed between the body 1 and the mounting portion 13a of the vehicle door 13. Since the rear seam portion 16 is covered with the body 1 and the mounting portion 13a of the vehicle door 13, the rear seam portion 16 is not exposed to the inside of the vehicle door 13. Further, since the side seam portion 14 is covered with the flange portion 12, the side seam portion 14 is also not exposed to the inside of the vehicle door 13. Therefore, water is prevented from infiltrating the second concave portion 3, in which the actuating mechanism 7 is disposed. Consequently, the actuating mechanism 7 is prevented from becoming rusted. 
     While the invention has been particularly shown and described with reference to preferred embodiment thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details can be made therein without departing from the spirit and scope of the invention.