BACK DOOR OPENING AND CLOSING APPARATUS
BACKGROUND OF THE INVENTION Field of the Invention [0001]
The present invention relates to a back door opening and closing apparatus of a vehicle.
Description of Related Art [0002]
Conventionally, there has been known a door opening and closing apparatus of a vehicle which can be opened by an opener having a luggage door provided in the vicinity of a driver's seat in a car {for example, see Japanese Unexamined Utility Model Application Publication No. S59-092172). [0003]
In the door opening and closing apparatus, the opener is coupled, via a cable, to a door latch device holding the luggage door to a body openably and closably. When a driver or the like operates the opener, the door latch device is operated through the cable so that the luggage door can be opened. [0004]
Referring to the apparatus which can thus open the luggage door by operating the opener in a car, it is necessary to provide, in the car, a safety device (a lock mechanism) capable of making the operation of the opener invalid according to laws of a country using the vehicle. [0005]
However, there is a problem in that an expensive actuator should be used

when a safety device (a lock mechanism) which can be operated in a car is to be
provided in a door opening and closing apparatus.
[0006]
In the case in which the door opening and closing apparatus is to be manufactured inexpensively, an actuator and the opener are not provided to abandon door opening itself in the car, accordingly, a door handle and a lock mechanism are provided to configure the door opening and closing apparatus. More specifically, the door handle enables the luggage door to be opened at an outside of the car. The lock mechanism can perform switching into a locking state in which the operation of the door handle is made invalid to disable door opening and an unlocking state in which the operation of the door handle is made valid to enable the door opening by a key operation for a key cylinder provided on the luggage door. [0007]
With the structure described above, however, in the case in which it is necessary to open a luggage door so as to make luggage or the like visible at time of security check (to be performed in India or the like) in a shopping mall, for example, a driver should get off a car to operate a key cylinder by means of a key, thereby bringing the lock mechanism into an unlocking state and to operate a door handle, thereby opening the luggage door. Also after the luggage door is closed, moreover, it is necessary to bring the lock mechanism into the locking state by using the key, which is troublesome.
SUMMARY OF THE INVENTION [0008]
It is an object of the present invention to provide a back door opening and

closing apparatus which can operate a lock mechanism on a car interior side and is
excellent in convenience regardless of inexpensiveness.
[0009]
In order to solve the problem mentioned above, the present invention provides a back door opening and closing apparatus including: a back door for opening and closing a rear opening portion of a body; a door handle provided on the back door; a striker provided on either the back door or the body; and a door latch device provided on the other, that is, the back door or the body, engaged with the striker and holding the back door in a closing position, the door latch device including: a fork which can be rotated from an open position to a full latch position by abutment on the striker; a claw lever for preventing the fork from returning from the full latch position to the open position by engagement with the fork; an open lever coupled to the door handle; a lock mechanism capable of performing switching into an unlocking state in which operating force of the door handle can be transmitted to the claw lever through the open lever or a locking state in which the transmission is disabled; a lock operating member provided in a car interior and capable of operating the lock mechanism; and a cable for coupling the lock mechanism of the door latch device to the lock operating member. [0010]
By this configuration, it is possible to switch the lock mechanism into an unlocking state or a locking state by simply operating the lock operating member on a car interior side. [0011]
It is preferable that the door latch device should be provided on the back door, and the lock mechanism of the door latch device and the cable should be coupled through a relay lever provided on the body.

[0012]
By this configuration, it is not necessary to arrange the cable in the back door In other words, conventionally, it is necessary to arrange the cable in the back door from a body side through a hinge portion of the back door which is rotatably attached to the body. However, such a hard arranging work is not required. Moreover, it is not necessary to extend the cable into the back door. For this reason, a short cable can be used. Furthermore, the cable is not arranged in the back door. Therefore, it is possible to prevent illegal operation at an outside, thereby enhancing theft prevention. [0013]
It is preferable that the relay lever should be rotatably attached to a base body portion for fixing the striker to the body or a bracket fixed to the base body portion. [0014]
By this configuration, it is also possible to fix the relay lever to the body by simply securing the base body portion of the striker to the body. Therefore, an assembly work to the body is made easy. [0015]
It is preferable that the cable should include an outer cable having a cylindrical shape and an inner cable provided movably along a longitudinal direction thereof in the outer cable, and a cable fixing portion holding an end of the outer cable should be integrally provided on the bracket. [0016]
Consequently, the configuration can be simplified. [0017]
It is preferable that an operating lever to be interlocked with the relay lever

should be provided on the lock mechanism of the door latch device, and the operating lever should include a first lock mechanism operating portion to be exposed to an outside so as to be operable through a first ojjening portion provided on the back door. [0018]
By this configuration, when the first lock mechanism operating portion is operated at the outside of the car to switch the lock mechanism into the locking state and to operate the back door to a closing position, the fork of the door latch device is mated with the striker in a full latch position and can be held in a closing position with the back door maintained in the locking state. In other words, a driver does not go out of a car but a person on the outside of the car operates the first lock mechanism operating portion to switch the lock mechanism, thereby closing the back door. Consequently, the back door can be closed in the locking state so that convenience can further be enhanced. [0019J
It is preferable that the relay lever can be engaged with the first lock mechanism operating portion of the operating lever. [0020]
By this configuration, the first lock mechanism operating portion can be caused to have two functions and a size of the operating lever exposed from the back door to the outside can be reduced. Therefore, the first opening portion can be small-sized to enhance an appearance. [0021]
Preferably, the door latch device includes a base plate, the open lever includes: a first lever to be attached to the base plate rotatably; and a second lever provided to be rotatable integrally with the first lever and to be relatively movable to an unlocking

position where engagement with the claw lever with respect to the first lever can be performed and a locking position where the engagement is disabled; the lock mechanism includes a lock lever for operating the second lever to the locking position and the unlocking position in engagement with the second lever interlockingly with the operating lever, and the lock lever includes a second lock mechanism operating portion to be exposed into a car interior so as to be operable through a second opening portion provided on the back door. [0022]
By this configuration, a passenger sitting on a back seat in a car interior can directly operate the lock mechanism. Consequently, convenience can further be enhanced. [0023]
The striker may be provided on the back door, and the door latch device may be provided on the body. [0024]
The relay lever may be configured from a first relay lever for switching the lock mechanism of the door latch device from an unlocking state to a locking state and a second relay lever for switching the lock mechanism from the locking state to the unlocking state. [0025]
According to the present invention, it is possible to switch the lock mechanism of the door latch device from the locking state to the unlocking state by operating the lock operating member provided in the vicinity of a driver's seat. When the lock mechanism is brought into the unlocking state, a person on an outside of a car other than a driver can open a door by operating the door handle of the back door. In other

words, the lock mechanism can be operated from the car interior. Therefore, the driver can open the back door by switching the state of the lock mechanism without going out of the car in security check or the like, for example. Consequently, convenience can be enhanced.
BRIEF DESCRIPTION OF THE DRAWINGS [0026]
Fig. 1 is a schematic view showing a back door opening and closing apparatus according to a first embodiment;
Fig. 2 is a perspective view in a locking state of a door latch device in Fig. 1;
Fig. 3 is a front view showing the door latch device in Fig. 2;
Fig. 4A is a front view showing a locking state of an open lever to be used in the door latch device of Fig. 3;
Fig. 4B is a front view showing an unlocking state of the open lever to be used in the door latch device of Fig. 3;
Fig. 5 is a front view showing a transition from the state illustrated in Fig. 3 to an unlocking state in which a lock operating member is operated;
Fig. 6 is a front view showing that the operation of the lock operating member is cancelled from the state illustrated in Fig. 5 and an unlocking state is thus brought;
Fig. 7 is a front view showing a back door illustrated in Fig. 1 as seen on a car inlerior side;
Fig. 8 is a perspective view showing a state in which the back door illustrated in Fig. 1 is opened as seen from a rear part of a vehicle;
Fig. 9 is a plan view showing a latch mechanism in a state in which the back door illustrated in Fig. 1 is opened (an open position);

Fig. 10 is a plan view showing the latch mechanism in a state in which the back door illustrated in Fig. 1 is being closed (a half latch position);
Fig. 11 is a plan view showing the latch mechanism in a state in which the back door illustrated in Fig. 1 is closed (a full latch position);
Fig. 12 is a front view immediately after rotation of a first relay lever is started in the locking state by a door latch device of such a type that a first cable and a relay lever are made into two sets according to a second embodiment;
Fig. 13 is a front view showing that the door latch device is brought into the unlocking state in Fig. 12;
Fig. 14 is a front view showing a state in which the operation of the lock operating member is canceled in Fig. 13;
Fig. 15 is a front view showing that the door latch device is brought into the locking state in Fig. 14;
Fig. 16 is a front view showing the locking state of the door latch device provided on a body side according to a third embodiment; and
Fig. 17 is a front view showing the unlocking state of the door latch device illustrated in Fig. 16.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0027]
(First Embodiment)
Fig. 1 shows a back door opening and closing apparatus 1 according to an embodiment of the present invention. The back door opening and closing apparatus 1 includes a back door 3 for opening and closing a rear opening portion of a body 2, a door handle (not shown) provided on the back door 3, a striker 4 provided on the body

2, and a door latch device 5 provided on the back door 3, engaged with the striker 4 and holding the back door 3 in a closing position. The door latch device 5 is screwed and fixed through a base 8 to a latch attaching portion 7 provided on an end face 3b of a door which is extended from an outer panel 6 configuring the back door 3. [0028]
As shown in Fig, 2, the striker 4 is substantially U-shaped and has both ends integrated with a base body portion 9 screwed and fixed to the body 2. One end of a bracket 10 is fixed to a part of the base body portion 9 by welding. The bracket 10 has an intermediate part bent and protruded toward an either side and a relay lever 11 is attached rotatably around a support shaft 11c extended in a vertical direction therein. The relay lever 11 is biased in one of rotating directions by a spring 1 Id and is thus placed in an initial position. One end of the relay lever 11 is a working portion I la for pressing and rotating an operating lever 19 which will be described below. As shown in Fig. 3, a coupling portion 1 lb to which a first cable 12 is to be coupled is formed on the other end of the relay lever 11. The first cable 12 is formed by an outer cable 12a having a cylindrical shape and an inner cable 12b arranged reciprocatably along a longitudinal direction of the outer cable 12a therein. One end of the inner cable 12b is connected to the coupling portion 1 lb of the relay lever 11. Moreover, the other end of the inner cable 12b is connected to a lock operating member 13 provided in a car interior, in detail, on a driver's seat. The outer cable 12a has one end fixed to a cable fixing portion 10a at the other end side of the bracket 10. The relay lever 11 is rotated from the initial position to a working position against biasing force of the spring 1 Id by an operation of the lock operating member 13. [0029]
As shown in Fig. 2, the door latch device 5 includes a base plate 14. The base

plate 14 is formed by a first surface portion (not shown} and a second surface portion
16 and both of them are substantially L-shaped.
[0030]
A latch base 17 is attached to the first; surface portion. A support piece 18 is
provided on a part of the latch base 17, and the operating lever 19 is supported
thereon rotatably around a first shaft portion 20. As shown in Fig. 9, a first stopper
21 and a second stopper 22 are formed on the latch base 17.
[0031]
As shown in Fig, 2, the operating lever 19 is substantially L-shaped and has one end side where a first lock mechanism operating portion 23 which can be pressed by the working portion 13 a of the relay lever 11 is formed. The first lock mechanism operating portion 23 is protruded toward the end face 3b of the back door 3 and is protruded from the back door 3 through a first opening portion 24 formed on the end face 3b of the back door 3 (see Figs. 7 and 8). A groove-shaped portion 25 is formed on the other end side of the operating lever 19. A first projection 54 of a lock lever 41 which will be described below is positioned on the groove-shaped portion 25. Consequently, when the relay lever 11 is rotated so that the first lock mechanism operating portion 23 is pressed by die working portion 1 la, the operating lever 19 is rotated from the initial position to the working position. [0032]
As shown in Fig. 9, a U-shaped groove 26 turned upward from a central part of a lower edge is formed on the latch base 17. Moreover, the latch base 17 is provided with a latch mechanism 27. [0033]
The latch mechanism 27 rotatably supports a fork 28 and a claw lever 29

between a first, surface portion (not shown) of the base plate 14 and the latch base 17 arranged on a lower surface side thereof (see Fig. 2). As shown in Fig. 2, a peripheral edge of the latch base 17 is protruded upward beyond the first surface portion and a latch block 30 is disposed therein and is further covered with a latch cover 31. [0034]
Returning to Fig. 9, the fork 28 is attached to the latch base 17 rotatably around a first rotating shaft 32. An engaging groove 33 turned from an outer edge toward the first rotating shaft 32 is formed on the fork 28. The striker 4 is engaged with or disengaged from the engaging groove 33. In the fork 28, moreover, a full latch step portion 35 and a half latch step portion 36 are formed on an outer edge of one of protruded pieces 34 divided into two parts by the engaging groove 33. A locking-portion 39 of the claw lever 29 can be locked with these step portions. The fork 28 is positioned in a full latch position and a half latch position respectively depending on each locking state. Furthermore, the fork 28 is biased in a counterclockwise direction in Fig. 9 by means of a spring (not shown) arranged around the first rotating shaft 32. If the fork 28 is not positioned by the claw lever 29, accordingly, it is rotated to an open position where an outer edge thereof abuts on the first stopper 21. [0035]
The claw lever 29 is attached to the latch base 17 rotatably around a second rotating shaft 37. The claw lever 29 includes an operated portion 38 and the locking portion 39 linked thereto at one end side. The claw lever 29 is biased in a clockwise direction around the second rotating shaft 37 by means of a spring which is not shown and ail outer edge thereof abuts on the second stopper 22 so that a rotating range is regulated. The operated portion 38 is pressed onto an open lever 40 which will be described below so that the ck\w lever 29 is rotated in the counterclockwise direction

around the second rotating shaft 37 in Fig. 9. [0036]
As shown in Figs. 3, 4A and 4B, the open lever 40 and the lock lever 41 are attached to the second surface portion 16. [0037]
The open lever 40 is configured from a first lever 42 and a second lever 43. [0038]
The first lever 42 is attached to the second surface portion 16 of the base plate 14 rotatably around a second shaft portion 44 between an initial position and a working position. A second cable 45 extended from the door handle is coupled to one end (an upper end) of the first lever 42. A spring 42a is locked between the other end (a side portion on a lower end) of the first lever 42 and the second surface portion 16 of the base plate 14, and the first lever 42 is biased in the counterclockwise direction and is thus placed in the initial position in Fig. 3. Moreover, the first lever 42 has an upper part of the second shaft portion 44 bent stepwise and an insertion hole 46 is formed thereon. Fig. 3 shows the locking state. [0039]
The second lever 43 has a slide hole 47 formed on a center and the second shaft portion 44 is slidably inserted therethrough. Consequently, the second lever 43 slides to an unlocking position where the claw lever 29 can be operated and a locking position where uhe operation is disabled. An engaging portion 48 is provided on an upper end of the second lever 43. The engaging portion 48 cannot slip off the insertion hole 46 with a tip part enlarged in a transverse direction in an insertion state in the insertion hole 46 of the first lever 42. The second lever 43 can slide with the first lever 42 by the second shaft portion 44 and the engaging portion 48 inserted

through the insertion hole 46, and both of them can be rotated integrally. A coupling portion 49 is extended from a side edge in a vicinal part of the slide hole 47 to the second lever 43. A slot 50 is formed on the coupling portion 49 and a second projection 55 of the lock lever 41 which will be described below is provided therein so that both members can be interlocked. Moreover, a lower end of the second lever 43 is bent stepwise and a tip part thereof serves as an operating portion 51 capable of pressing and operating the operated portion 38 of the claw lever 29. [0040]
The lock lever 41 is attached to the second surface portion 16 of the base plate 14 rotatably between the locking position and the unlocking position around a third shaft portion 52. The lock lever 41 is biased by an action spring 41a provided between the lock lever 41 and the second surface portion 16. A biasing direction through the action spring 41a is varied depending on a rotating position of the lock lever 41. Specifically, the action spring 41a biases the lock lever 41 so as to be maintained in the unlocking position in a state in which the lock lever 41 is rotated in the clockwise direction around the third shaft portion 52. To the contrary, in a state in which the lock lever 41 is rotated in the counterclockwise direction, the action spring 41a biases die lock lever 41 so as to be maintained in the locking position. A second lock mechanism operating portion 53 which is protruded toward a car interior side and is bar-shaped is formed on one end of the lock lever 41. The second lock mechanism operating portion 53 is protruded from a second opening portion 3a formed on an inner panel of the back door 3 and can be operated in the car interior. As shown in Fig. 2, the first projection 54 is formed in the vicinity of the third shaft portion 52 in an intermediate part of the lock lever 41. The first projection 54 is disposed in the groove-shaped portion 25 of the operating lever 19 and a rotating

operation of the operating lever 19 is transmitted to the lock lever 41. Furthermore, the second projection 55 is formed on the other end of the lock lever 41. The second projection 55 is inserted through the slot 50 formed on a communicating part of the second lever 43, and the lock lever 41 and the second lever 43 of the open lever 40 are operated interlockingly. As described above, the lock mechanism for switching the locking and unlocking states of the door latch device 5 is configured from the relay lever 11, the operating lever 19, the lock lever 41 and the second lever 43 of the open lever 40. [0041]
Next, a description will be given of the operation of the back door opening and closing apparatus 1 having the configuration described above. [0042]
In a state in which the back door 3 is opened, the fork 28 is biased in the counterclockwise direction around the first rotating shaft 32 and is thus rotated to an open position to open the engaging groove 33 in the vicinity of an inlet of the U-shaped groove 26 of the latch base 17 as shown in Fig. 9. The claw lever 29 is biased in the clockwise direction around the second rotating shaft 37 and abuts on the second stopper 22. [0043]
When the back door 3 is closed, tile striker 4 on the body side enters the U-shaped groove 26 of the latch base 17 to press the fork 28 and rotates the fork 28 in the clockwise direction around the first rotating shaft 32 as shown in Fig. 10. Consequently, the locking portion 39 of the claw lever 29 is locked with the half latch step portion 36 of the fork 28, and the fork 28 reaches the half latch position. Furthermore, when the striker 4 enters the U-shaped groove 26, the fork 28 is further

rotated so that the locking portion 39 of the claw lever 29 is locked with the full latch step portion 35 as shown in Fig. 11, Consequently, the striker 4 is locked by the fork 28 so that the back door is held into the closing state. [0044]
If the back door 3 (the lock mechanism of the door latch device 5) is set into the unlocking state, it is possible to open the back door 3 by operating the door handle to rotate the open lever 40 though the second cable 45. In other words, in the unlocking state, the lock lever 41 is rotated into the unlocking position and the second lever 43 slides to the unlocking position. In this state, the operated portion 38 of the claw lever 29 can be pressed and operated by the operating portion 51 of the second lever 43. If the door handle is operated to rotate the first lever 42 through the second cable 45, accordingly, it is possible to rotate the claw lever 29, thereby cancelling the engaging state of the fork 28 and opening the back door 3. [0045]
On the other hand, if the back door 3 is set into the locking state, the back door 3 cannot be opened even if the door handle is operated to rotate the open lever 40 through the second cable 45. In other words, the lock lever 41 is rotated into the locking position and the second lever 43 slides to the locking position. Consequently, the operated portion 38 of the claw lever 29 is separated from the operating portion 51 of the second lever 43 so that a pressing operation is disabled. Even if the first lever 42 is rotated, therefore, the claw lever 29 cannot be interlocked so that the engaging state of the fork 28 is maintained. For this reason, the back door 3 cannot be opened. [0046]
In the back door opening and closing apparatus 1. moreover, it is possible to switch the back door 3 into the unlocking state or the locking state by operating the

lock lever 41 in the car interior. [0047]
In other words, as shown in Figs. 7 and 8, the second lock mechanism operating portion 53 of the lock lever 41 is exposed to the car interior from the second opening portion 3a. formed on the inner panel of the back door 3. By operating the second lock mechanism operating portion 53, therefore, it is possible to easily switch the lock lever 41 into the unlocking position or the locking position. When the second lock mechanism operating portion 53 is operated to rotate the lock lever 41 to the locking position, the second lever 43 slides upward to bring the locking state in which the claw lever 29 cannot be operated. On the other hand, when the second lock mechanism operating portion 53 is operated to rotate the lock lever 41 to the unlocking position, the second lever 43 slides downward to bring the unlocking state in which the claw lever 29 can be operated. [0048]
In the back door opening and closing apparatus 1, moreover, it is possible to switch the back door 3 from the locking state into the unlocking state by operating the lock operating member 13. [0049]
In other words, when the lock operating member 13 is operated, the relay lever 11 is rotated through the first cable 12 as shown in Fig. 3. In the locking state, the second lever 43 slides upward with respect to the first lever 42 and the lock lever 41 is rotated to the locking position in the clockwise direction around the third shaft portion 52. Moreover, the operating lever 19 is rotated in the clockwise direction around the first shaft portion 20 and the first lock mechanism operating portion 23 is brought into a state capable of pressing by the working portion 1 la of the relay lever 11. When the

relay lever 11 is rotated, accordingly, the operating lever 19 is rotated in the counterclockwise direction around the first shaft portion 20 so that the lock lever 41 is rotated to the unlocking position in the clockwise direction around the third shaft portion 52 as shown in Fig. 5. Consequently, the second lever 43 slides downward so that the operated portion 38 of the claw lever 29 can be operated by the operating portion 51. [0050]
If the operation of the lock operating member 13 is ended, the relay lever 11 is returned to an original position by the biasing force of the spring 1 Id and the inner cable 12b also enters an inside of the outer cable 12a as shown in Fig. 6. On the other hand, the lock lever 41 rotated to the unlocking position is maintained in that position by the operation of the action spring. Consequently, the operating lever 19 also stays in the working position moved from an initial position and the second lever 43 also stays in the unlocking position moved from the locking position. [0051]
If the back door 3 is thus brought into the unlocking state, the door handle is operated so that the second lever 43 is rotated together with the first lever 42 through the second cable 45 and the claw lever 29 is rotated to cancel the engaging state with the fork 28 so that the back door 3 is opened. [0052]
When the first lock mechanism operating portion 23 is operated in the state in which the back door 3 is opened, moreover, the operating lever 19 is rotated in the clockwise direction around the first shaft portion 20 to rotate the lock lever 41 to the locking position. Consequently, the second lever 43 slides to an. upper locking position. When the back door 3 is closed, then, the fork 28 is rotated by the striker 4

and the locking portion 39 of the claw lever 29 is locked with the full latch step portion 35. In this state, the second lever 43 is moved to the locking position. Therefore, the back door 3 is brought into the locking state and cannot be opened depending on the operation of the door handle. [0053]
By operating the lock operating member 13 on a driver's seat in the car interior, thus, it is possible to switch the back door 3 from the locking state into the unlocking state. If the door handle is operated at the outside of the car, therefore, it is possible to open the back door 3 without causing a driver to get off. At time of security check in a shopping mall (to be performed in India or the like), for example, tire driver can open the back door 3 without getting off and can close the back door 3 to bring the locking state, which is convenient. [0054]
(Second Embodiment)
Figs. 12 to 15 show a back door opening and closing apparatus 1' according to a second embodiment. The back door opening and closing apparatus 1' is different from the first embodiment in that a relay lever 11 is configured from a first relay lever 11A and a second relay lever 1 IB, and the other portions are the same. In this embodiment, the same components have the same reference numerals and their description will be omitted. [0055]
The first relay lever 11A and the second relay lever 1 IB can be operated by a first lock operating member and a second lock operating member (neither of them are shown) provided on a driver's seat in a car interior through a first relay cable 12A and a second relay cable I2B, respectively. The first relay lever 11A and the second relay

lever 1 IB are coaxially supported on a support shaft lie respectively, and each working portion is positioned to be engageable with both sides in a working direction of a first lock mechanism operating portion 23 of an operating lever 19, respectively. The first relay lever 11A and the second relay lever 1 IB are biased to return to an initial position placed before pressing the operating lever 19 through a spring 1 Id. When the first lock operating member is operated, as illustrated in Fig. 12, the first relay lever 11A is rotated in a clockwise direction to press the first lock mechanism operating portion 23 of the operating lever 19 and to rotate the operating lever 19 from an initial position shown in Fig. 12 to a working position shown in Fig. 13. Moreover, when the second lock operating member is operated, as illustrated in Fig. 14, the second relay lever 1 IB is rotated in a counterclockwise direction to press the first lock mechanism operating portion 23 of the operating lever 19, thereby rotating the operating lever 19 from a working position shown in Fig. 14 to an initial position shown in Fig. 15. [0056]
(Third Embodiment)
Although the striker 4 and the door latch device 5 are provided on the body 2 and the back door 3 respectively in the first and second embodiments, the striker 4 and the door latch device 5 are provided on the back door 3 and the body 2 respectively in a third embodiment. [0057]
Figs. 16 and 17 show a door latch device 5' provided on a body 2. In the door latch device 5', an operating lever 19 is not required and a first cable 12 is directly coupled to a lock lever 41. in other words, an inner cable 12b of the first cable 12 is connected to a coupling portion 56 provided in the vicinity of a third shaft portion 52 of

the lock lever 41. Since the other configurations are the same as those in the first embodiment, the same components have the same reference numerals and description thereof will be omitted. [0058]
When a lock operating member 13 provided on a driver's seat in a car interior is operated in a locking state shown in Fig. 16, the coupling portion 56 of the lock lever 41 is pulled by the inner cable 12b of the first cable 12 as shown in Fig. 17. Consequently, the lock lever 41 is rotated in a clockwise direction around the third shaft portion 52 so that a second lever 43 is moved downward with respect to a first lever 42. Thus, a claw lever 29 (not. shown in Fig. 17} can be operated by the second lever 43. Accordingly, a door handle is operated to rotate the second lever 43 together with the first lever 42 through a second cable 45 so that a back door 3 can be opened in the same manner. [0059]
The door latch device 5 according to the present invention is not restricted to the configurations according to the embodiments and various changes can be made. [0060]
Although the relay lever 11 is attached to the bracket 10 welded to the base body portion 9 fixing the striker 4 in the embodiments, it may be directly attached to the base body portion 9. [0061]
Although the relay lever 11 and the operating lever 19 are interlocked by engagement of the first projection 54 formed on the operating lever 19 with the groove-shaped portion 25 formed on the relay lever 11 in the embodiments, it is also possible to perform direct engagement with the first lock mechanism operating portion 23 of the

operating lever 19. Consequently, it is possible to cause the first lock mechanism operating portion 23 of the operating lever 19 to have two functions including an operation to be performed in the car interior and an operation to be performed through the relay lever 11 utilizing the lock operating member 13, thereby obtaining a simple configuration having no first projection 54.

What is claimed is:
1. A back door opening and closing apparatus comprising:
a back door for opening and closing a rear opening portion of a body; a door handle provided on the back door; a striker provided on either the back door or the body; and a door latch device provided on the other of the back door or the body, engaged with the striker and holding the back door in a closing position, the door latch device including:
a fork which can be rotated from an open position to a full latch position by abutment on the striker;
a claw lever for preventing the fork from returning from the full latch position to the open position by engagement with the fork; an open lever coupled to the door handle;
a lock mechanism capable of performing switching into an unlocking state in which operating force of the door handle can be transmitted to the claw lever through the open lever or a locking state in which the transmission is disabled;
a lock operating member provided in a car interior and capable of operating the lock mechanism; and
a cable for coupling the lock mechanism of the door latch device to the lock operating member.
2. The back door opening and closing apparatus according to claim 1,
wherein the door latch device is provided on the back door, and the lock mechanism and the cable in the door latch device are coupled
through a relay lever provided on the body.

3. The back door opening and closing apparatus according to claim 2,
wherein the relay lever is rotatably attached to a base body portion for fixing
the striker to the body or a bracket to be fixed to the base body portion.
4. The back door opening and closing apparatus according to claim 3,
wherein the cable includes an outer cable having a cylindrical shape and an
inner cable provided movably along a longitudinal direction of the outer cable in the outer cable, and
a cable fixing portion holding an end of the outer cable is integrally provided on the bracket.
5. The back door opening and closing apparatus according to claims 2 to 4,
wherein an operating lever to be interlocked with the relay lever is provided on
the lock mechanism of the door latch device, and
the operating lever includes a first lock mechanism operating portion to be exposed to an outside so as to be operable through a first opening portion provided on the back door.
6. The back door opening and closing apparatus according to claim 5,
wherein the relay lever can be engaged with the first lock mechanism
operating portion of the operating lever.
7. The back door opening and closing apparatus according i.o claim 5,
wherein the door latch device includes a base plate,

the open lever includes:
a first lever to be attached to the base plate rotatably; and a second lever provided to be rotatable integrally with the first lever and to be relatively movable to an unlocking position where engagement with the claw lever with respect to the first lever can be performed and a locking position where the engagement is disabled; the lock mechanism includes a lock lever for operating the second lever to the locking position and the unlocking position in engagement with the second, lever interlockingly with the operating lever, and
the lock lever includes a second lock mechanism operating portion to be exposed into a car interior so as to be operable through a second opening portion provided on the back door.
8. The back door opening and closing apparatus according to claim 1,
wherein the striker is provided on the back door, and
the door latch device is provided on the body.
9. The back door opening and closing apparatus according to claims 2 to 7,
wherein the relay lever is configured from a first relay lever for switching the
lock mechanism of the door latch device from an unlocking state to a locking state, and a second relay lever for switching the lock mechanism from the locking state to the unlocking state.