Door Lock Device

Abstract

A door lock device including a base plate, a bracket mounted on the base plate, two shafts fixed to the base plate and the bracket, one of the shafts being held in common by a first latch member and a first pawl, the other of the shafts being held in common by a second latch member and a second pawl, biasing means for maintaining the first and second latch members and the first and second pawls in normal states thereof, a striker in contact with the first and second latch members so as to move them swingingly against the biasing means, the first and second pawls being opposed to the second and first latch members respectively for retaining them in the half-latched or full-latched position, and means for simultaneously releasing the retaining means for the first and second latch members so as to make them return to their normal states from the half-latched or full-latched position.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a door lock device for vehicles and more particularly to an improved door latch means enhancing the safety of the vehicle.

2. Description of the Prior Art:

It has become increasingly more important for a motorcar to be safe, comfortable and to meet the ecological demands of present times. Not only has there been extreme legislative pressures on the automobile industry, but the changing standards of living have brought even greater public demands. One primary area of concern for the safety of the automobiel has been directed to the door lock device. Although prior art devices have been concerned with prevention of inadvertent opening of the automobile doors, especially in the event of collision, such prior art devices have not been entirely satisfactory.

SUMMARY OF THE INVENTION

It is therefore a principle object of the present invention to provide an improved door lock device wherein latch means are provided in a double arrangement to increase the strength of the mechanism, such that in the event one of the latch means between a latch member and a pawl is released, engagement can be retained by the other latch means, and thereby it is possible to raise the security of such door lock higher than in conventional devices.

Another object of the present invention is to provide an improved door lock device wherein each set of latch member and associated pawl hold a common pivot shaft, thereby permitting the present device to be a compact structure which is low cost in manufacture.

Briefly, in accordance with one embodiment of the present invention, these and other objects are attained by providing a door lock device including a base plate, a bracket mounted on the base plate, two shafts fixed to the base plate and the bracket, one of the shafts being held in common by a first latch member and a first pawl, the other of the shafts being held in common by a second latch member and a second pawl, biasing means for maintaining the first and second latch members and the first and second pawls in normal states thereof, a striker in contact with the first and second latch members so as to move them swingingly against the biasing means, the first and second pawls being opposed to the second and first latch members respectively for retaining them in the half-latched or full-latched position, and means for simultaneously releasing the retaining means for the first and second latch members so as to make them return to their normal states from the half-latched or full-latched position.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description when considered in connection with the accompanying drawings, in which:

FIG. 1 is an elevational view showing one embodiment of the present invention in full-latch engagement;

FIG. 2 is a cutaway view of FIG. 1 showing the internal construction of the present invention;

FIG. 3 is a cross section taken along the line A--A of FIG. 1;

FIG. 4 is an elevational view of the present invention in the door-open position;

FIG. 5 is an elevational view of the present invention in half-latch engagement;

FIG. 6 is an elevational view of the present invention in full-latch engagement;

FIG. 7 is a rear elevational view showing the relasing mechanism of the present invention in the status before effecting the releasing operation;

FIG. 8 is a rear elevational view showing the releasing mechanism in the status after releasing the engagement of the latch means;

FIG. 9 is a side elevation viewed in the direction of the arrow B of FIG. 7;

FIG. 10 is an elevational view of the striker engaging with the latch means of the present invention; and

FIG. 11 is a side elevation of FIG. 10.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Referring now to FIGS. 1 - 3, a base plate 10 together with a bracket 12 forms a body for retaining and housing the operative members of the present door lock device. A first shaft 14 is retained within hole 18 of the base plate 10 and hole 20 of the bracket 12 and a second shaft 16 is retained within a hole 22 of the base plate 10 and hole 24 of the bracket 12. The numeral 26 represents a first latch member, 28 a second latch member, 30 a first pawl and 32 a second pawl. The first latch member 26 and the first pawl 30 are held in common on the first shaft 14 and are arranged so as to swingingly move around the shaft 14. The second latch member 26 and second pawl 32 are held in common on the second shaft 16 and are arranged so as to swingingly move around the shaft 16. The first latch member 26 is opposed to the second pawl 32, and the second latch member 28 is opposed to the first pawl 30. A first tooth face 34 and second tooth face 36 are provided on the first latch member 26, which may engage with a tooth 38 of the second pawl 32. A first tooth face 40 and second tooth face 42 are provided on the second latch member 28, which may engage with the tooth 44 of the first pawl 30. A pawl return spring 46 has hooks 52, 58 caught by a notch 50 provided on an arm 48 of the first pawl 30 and by a notch 56 provided on an arm 54 of the second pawl 32, respectively, such that the spring 46 may urge the first pawl 30 in clockwise direction and the second pawl 32 in counter-clockwise direction with the shafts 14 and 16 as their axes. A latch spring 60 includes a first coiled portion 62 and a second coiled portion 64 arranged in peripheries of the first shaft 14 and the second shaft 16, respectively. The first latch member 26 and the second latch member 28 provide notches 66 and 68 respectively to which are hooked, with a predetermined load, arms 70 and 72 respectively provided at the latch spring 60 so as to urge the first latch member 26 in a clockwise direction, and the second latch member 28 in a counter-clockwise direction. Arms 74 and 76 are formed at the first latch member 26 and the second latch member 28, respectively, so that they may engage with a U-shaped arm 80 of a striker 78, as shown in FIGS. 10 and 11. A lever 82 which is mounted to the bracket 12 by the shaft 84, swingingly moves around shaft 84, as viewed in FIGS. 7 and 8. The lever includes a contact portion 90 which may be in contact with the arm 54 of the second pawl 32 through a conical hole 86 in the bracket 12, so as to rotate the second pawl 32 in a counterclockwise direction, as shown in FIGS. 7 and 8, by a suitable angle. The lever 82 also provides a pin 96 so as to transmit the movement of the lever 82 to a lever 94 through an elongated hole 92 in the bracket 12. The pin 96 is engageable, with a small amount of play, with an elongated hole 98 provided in the lever 94. The lever 94 is mounted on the bracket 12 by a shaft 100 so as to swingingly move around the shaft 100. The lever 94 includes a contact portion 102 which may be in contact with the arm 48 of the first pawl 30 so as to make the rotation of the first pawl 30 in the clockwise direction by a suitable angle. Four holes 104 are provided at the base plate 10 and four trapped holes 106 are provided at the bracket 12, both for fitting the door locking device to the door (not shown). The striker 78, shown in FIGS. 10 and 11, is secured by a screw to the side of the vehicle body through the fitting holes 108, so as to permit engagement between the U-shaped arm 80 and the door locking device.

With reference first to FIGS. 4 to 6, the engaging process of the present device will be described. FIG. 4 shows the present device in a door-open status. When the door is operated from the open to closed status, the U-shaped arm 80 of the striker 78, fitted to the vehicle body, would advance toward the second tooth-face 36 of the first latch member 26 and the second tooth-face 42 of the second latch member 28. The U-shaped arm 80 then simultaneously pushes the second tooth-faces 36 and 42 of the first and second latch members 26 and 28, respectively. Accordingly, the first latch member 26 and the second latch member 28 rotate against each load of arms 70 and 72 of the latch spring 60 with the first shaft 14 and the second shaft 16 as axes in the counterclockwise direction and the clockwise direction, respectively. When they have rotated through predetermined angles, the first tooth face 34 of the first latch member 26 would engage with the tooth 38 of the second pawl 32 with the clockwise rotation of the second pawl 32 against the spring 46, and the first tooth-face 40 of the second latch member 28 would engage with the tooth 44 of the first pawl 30 with the counterclockwise rotation of the pawl 30 against the spring 46, as shown in FIG. 5. This position represents the half latched status. When the U-shaped arm 80 directly advances, the rotating angles of the first latch member 26 and the second latch member 28 would become large, such that the engagement between the first tooth-face 34 of the first latch member 26 and the tooth 38 of the second pawl 32 may be released, and, at the same time, the engagement between the first tooth-face 40 of the second latch member 28 and the tooth 44 of the first pawl 30 may be released. The tooth 38 of the second pawl 32 is then engaged with the second tooth-face 36 of the first latch member 26, and the tooth 44 of the first pawl 30 is engaged with the second tooth face 42 of the second latch member 28. This position represents the full latched status as shown in FIG. 6. The operation for releasing the engagement will now be described with reference to FIGS. 7 - 9. FIG. 7 shows the door closed status. The lever 82 is operatively connected to the door handle through a link means (not shown) and is swingably pivotably fitted to the bracket 12 by the shaft 84. When lever 82 is made to swingingly move in the counterclockwise direction, the contact portion 90, which is in contact with the arm 54 of the second pawl 32 through the conical hole 86 bored at the bracket 12, permits the pawl 32 to rotate in the counterclockwise direction centering around the shaft 16, as shown in FIGS. 7 and 8, until the engagement between the second tooth-face 36 of the first latch member 26 and the tooth 38 of the second pawl 32 is completely released. Accompanying with this operation, the pin 96, provided on the lever 82, is engaged, with a little amount of play, through the elongated hole 92 bored in the bracket 12 with the elongated hole 98 of the lever 94. Lever 94 is swingably pivotably fitted to the bracket 12 by the shaft 100, so that the lever 94 may move swingingly, with the shaft 100 as an axis, in the clockwise direction. At the same time, the contact portion 102, which is in contact with the arm 48 of the first pawl 30 may permit the pawl 30 to rotate in the clockwise direction until the engagement between the second tooth-face 42 of the second latch member 28 and the tooth 44 of the first pawl 30 is completely released. Such operation could be effected against the load of the pawl return spring 46. As the result, the first latch member 25 and the second latch member 28 are both completely released from their engagements and accordingly, owing to the load of arms 70 and 72 of the latch spring 60, the first latch member 26 rotates in the counterclockwise direction until the face 110 of the first latch member 26 makes contact with the face 112 of the bracket 12, as viewed in FIG. 8. The second latch member 28 rotates in the clockwise direction until the face 114 of the second latch member 28 makes contact with the face 116 of the bracket 12, as also shown in FIG. 8. This position represents the door open status of the present device.

Obviously, numerous modifications and variations of the present invention are possible in light of these teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

Claims

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A door lock device, comprising:

a base plate;

a bracket mounted on said base plate;

two shafts fixed to said base plate and said bracket;

one of said shafts being held in common by a first latch member and a first pawl;

the other of said shafts being held in common by a second latch member and a second pawl;

biasing means for maintaining said first and second latch members and said first and second pawls in normal states thereof, respectively;

a striker capable of contact with said first and second latch members so as to move them swingingly against said biasing means;

said first and second pawls being opposed to said second and said first latch members, respectively, for retaining them in the half-latched or the full-latched position; and

means for simultaneously releasing said retaining means for said first and said second latch members so as to make them returned to their normal states from said half-latched or full-latched position.

2. A door lock device as set forth in claim 1, wherein said biasing means for said latch members is tortioned therebetween and comprises first and second coiled portions arranged in peripheries of said shafts, respectively.

3. A door lock device as set forth in claim 1, wherein said biasing means for said pawls is a coil spring tortioned therebetween.

4. A door lock device as set forth in claim 1, wherein said means for releasing said retaining means comprises a first lever pivotably swingably mounted on said bracket for engaging with one of said pawls and releasing it from engagement with one of said latch members and a second lever pivotaly swingably mounted on said bracket and operatively connected to said first lever for engaging with the other of said pawls for releasing it from engagement with the other of said latch members in linkage with said first lever.