GB2528747A

GB2528747A - Vehicle door latch device

Info

Publication number: GB2528747A
Application number: GB1508531.9A
Authority: GB
Inventors: Yuji Yoda; Takao Taga
Original assignee: Mitsui Kinzoku ACT Corp
Current assignee: Mitsui Kinzoku ACT Corp
Priority date: 2014-05-27
Filing date: 2015-05-18
Publication date: 2016-02-03
Anticipated expiration: 2035-05-18
Also published as: JP2015224457A; GB201508531D0; JP6361042B2; GB2528747B

Abstract

A vehicle door latch device, a body has an engagement mechanism engagable with a striker of a vehicle body to close a door. A casing 11 and a cover 12 are provided. In the casing, an operation mechanism is provided and switched between unlocking state enabling the engagement mechanism to disengage from the striker and a locking state disabling it. A metal protector cover 31 comprises an upper protection wall 311 which covers and protects an upper bound portion of the casing and cover and a whole upper area thereof, and holds upper parts of the casing and cover, thereby improving antitheft performance against a burglar prying casing and cover apart. The protective cover may include a protection wall 314 for a key cylinder mounting portion 119. A water proof cover 30 may be provided.

Description

Intellectual Property Office Application No. GB1508531.9 RTTVI Date:23 November 2015 The following terms are registered trade marks and should be read as such wherever they occur in this document: Thatcham (Pages 1, 3 and 9) Intellectual Property Office is an operating name of the Patent Office www.gov.uk/ipo

SPECIFICATION

VEHICLE DOOR LATCH DEVICE

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a vehicle door latch device providing antitheft performance.

[0002] JP5070649B2 discloses a conventional vehicle door latch device comprising a body having an engagement unit that comprises a latch engagable with a striker of a vehicle body and a ratchet engagable with the latch; a casing fixed to the body; an operation unit that is disposed in the casing and can switch between an unlocking state in which a door can be opened by disengaging the latch from the striker and a locking state in which the door cannot be opened; and a cover mounted to the casing over the operation unit.

[0003] The door latch device comprises a synthetic-resin waterproof cover for preventing rainwater from coming into the body or casing, over the upper parts of the casing and cover. The waterproof cover acts as a protection wall.

So it will be difficult to move the operation unit in the casing in a unlocking direction to open the door by inserting a special tool into a gap between an outer panel and a glass of the door and deform ing the casing or cover.

[0004] However, the door latch device with the waterproof cover can cause the following problem.

The waterproof cover is made of synthetic resin having low strength.

The waterproof cover itself can be deformed and broken by the tool inserted in the door. A bound portion between the casing and the cover is forcedly opened and the operation unit in the casing is shifted in an unlocking direction, so that the door is opened [0005] Recently, in the United Kingdom, the Thatcham Antitheft Performance Standards have been provided by THATCHAM (The Motor Insurance Repair Research Centre) and applied to motorcars sold in the country. The Standards require over two minute standing against invasion into the interior of a vehicle if a motorcar is attacked by a burglar. The door latch device with the foregoing synthetic-resin waterproof cover involves the disadvantage and does not meet the Standards in UK.

SUMMARY OF THE INVENTION

[0006] In view of the disadvantage, it is an object of the invention to provide a a vehicle door latch device improving antitheft performance against a burglar greatly.

[0007] The present invention solves the problem as below.

According to the first invention, there is provided a vehicle door latch device comprising: a body fixed in an inner surface of a door and including an engagement mechanism that is engagable with a striker of a vehicle body; a casing mounted to the body and including an operation mechanism switchable between an unlocking state in which the engagement mechanism can disengage from the striker and a locking state in which the engagement mechanism cannot disengage from the striker in a parts-holding portion which has an opening toward an interior of a vehicle; a cover fixed to the casing and closing the opening of the parts-holding portion; and a metal protector having an upper protection wall covering an upper bound portion of the casing and the cover and its upper surface, the metal protector holding upper parts of the casing and the cover.

[0008] According to the second invention, there is provided the vehicle door latch device in the first invention wherein the protector has a front protection wall which suspends from the upper protecting wall, and covers and protects at least an upper part of front surfaces of the casing and the cover which do not face an inner surface of the door.

[0009] According to the third invention, there is provided the vehicle door latch device of the first or second invention wherein the protector comprises a key-cylinder-mounting-portion protection wall which is continuous with the upper protection wall, and covers and protects an upper surface of a key-cylinder mounting portion formed on an upper part of the parts-holding portion.

[0010] According to the fourth invention, there is provided the vehicle door latch device of any one of the first to third inventions wherein the protector comprises an outer protection wall which covers and protects at least an upper part of an outer side of the part-holding portion which does not face of the inner surface of the door.

[0011] According to the fifth invention, there is provided the vehicle door latch device of any one of the first to fourth inventions wherein a waterproof cover covers whole upper surfaces of the casing and the cover and a vertical surface close to the upper surface, the whole waterproof cover being covered with the protector.

[0012] According to the vehicle door latch device, the upper bound portion of the casing and cover and the whole upper area are covered with and protected by the upper protection wall of the metal protector. Hence, even if a special tool is inserted into a gap between an outer panel of the door and a door glass, it will become difficult to forcedly open the bound portion of the casing and cover by the tool or to deform and break the upper part of the casing and cover, thereby improving antitheft performance against a burglar.

It becomes little to break the door open by moving the operation mechanism in the casing in the unlocking direction by the tool. The metal protector enables the door latch device to clear the Thatcham Antitheft Performance Standards in UK.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a front elevational view of a vehicle door latch device according to the present invention viewed from the back of the vehicle; FIG. 2 is a side elevational view of the door latch device viewed from the interior of the vehicle; FIG. 3 a side elevational view showing the inside of an operation unit without a cover; FIG. 4 is an exploded perspective view viewed from the front outside of the vehicle before a waterproof cover and a protector are mounted to a casing and a cover; FIG. 5 is a perspective view after mounting; FIG. 6 is an exploded perspective view before the waterproof cover and protector are mounted to the casing and cover; and FIG. 7 is a perspective view after mounting.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0014] In FIGS. 1-3, a door latch device 1 is attached on the inner side of the rear end of a front door D of a motor vehicle and comprises an engagement unit 3 with an engagement mechanism 2 for holding the door 0 in a closed position, and an operation unit 4 connected to the engagement unit 3.

[0015] The engagement unit 3 has a synthetic-resin body 5 fixed on an inner surface Dl of the door D. The body 5 includes the engagement mechanism 2 which comprises a latch 7 engagable with a striker 6 of a vehicle body and a ratchet 8 engagable with the latch 7. On the front surface of the body 5, an opening lever (not shown) is pivotally mounted to turn together with the ratchet 8. When the door D is closed, the striker 6 engages with the latch 7 and the ratchet 8 engages with the latch 7 thereby preventing the latch 7 from pivoting in an opening direction, so that the door D is closed.

[0016] The operation unit 4 comprises an approximately L-shaped synthetic-resin casing 11 mounted on a front surface of the body 3; and a synthetic-resin cover 12 that closes an interior-opening surface of a parts-holding portion 118 of the casing 11. In FIG. 3, the inside of the operation unit 4 is shown without the engagement unit 3 and cover 12.

[0017] The parts-holding portion 118 of the casing 11 comprises a first motor 13 for locking/unlocking; a worm wheel 14 that is pivotally mounted via a pivot shaft 111 fixed to the casing 11 and extending transversely of the vehicle; a second motor 15 for double-locking; a blocking lever 16 that is pivotally mounted via a pivot shaft 112 of the casing 11 and pivoted at a predetermined angle with a worm 151 driven by the second motor 15; a first key lever 17 that can pivot from a neutral position in a locking direction (clockwise in FIG. 3) and in an unlocking direction (counterclockwise in FIG. 3) with locking/unlocking action by a key cylinder KC on the exterior of the door D; a second key lever 18 that is coupled at the upper end to a lower part of the first key lever 17 and can pivot at a predetermined angle from a neutral position in FIG. 3 in a locking direction (clockwise in FIG. 3) and in an unlocking direction (counterclockwise in FIG. 3) with an action of the first key lever 17 by the key cylinder KC; a connecting lever 19 that is pivotally mounted via a pivot shaft 113 with the second key lever 18 and can pivot from an unlocking position in FIG. 3 in a locking direction (clockwise in FIG. 3); a first locking lever 20 that is pivotally mounted via a pivot shaft 114 of the casing 11 between the casing 11 and cover 12 and can pivot from an unlocking position in FIG. 3 in a locking direction (counterclockwise) with rotation of the worm wheel 14 driven by the key cylinder KC, locking knob LK and first motor 13; a second locking lever 21 that is pivotally mounted via the pivot shaft 114 with the first locking lever 20, moves with the first locking lever 20 by a torsion coil spring 33 acting to the first locking lever 20 and can pivot with the connecting lever 19 to an unlocking position in FIG. 3 and a locking position (counterclockwise in FIG. 3); a first lift lever 22 coupled to the second locking lever 21 to turn with the second locking lever 21 from an unlocking position in FIG. 3 in a locking direction (counterclockwise in FIG. 3) and vice versa, the first lift lever 22 being movable from the locking position in an opening direction upward when the second locking lever 21 is in the locking position and movable from the unlocking position in an opening direction upward when the second locking lever 21 is in the unlocking position; a second lift lever 23 pivoted via the same shaft as the first lift lever 22 and movable with the first lift lever 22 to an unlocking position and a locking position (counterclockwise in FIG. 3) and in an opening direction upward; an inside lever 24 that is pivotally mounted via a pivot shaft 115 of the casing 11 and pivots at a predetermined angle from a standby position in FIG. 3 in an opening direction (clockwise) with an inside handle IH on the interior side of the door D; and an outside lever 25 that is pivotally mounted via a pivot shaft 116 at the lower part of the casing 11, an interior end 251 of the outside lever 25 being shakably coupled to the first and second lift levers 22, 23, an exterior connecting portion 252 of the outside lever 25 being coupled to an outside handle on the exterior side of the door D. [0018] An operation mechanism 26 comprises the first motor 13, the worm wheel 14, the connecting lever 19, the first locking lever 20, the second locking lever 21, etc. and is switched between an unlocking state enabling the engagement mechanism 2 to disengage from the striker 6 and a locking state disabling the engagement mechanism 2 to disengage from the striker 6. The locking state of the operation mechanism 26 means that at least the connecting lever 19 and second locking lever 21 is in the locking position and the unlocking state of the operation mechanism 26 means that the connecting lever 19 and first and second locking levers 20, 21 are in the unlocking position respectively.

[0019] At the lower part of the casing 11, there is provided a synthetic-resin lid member 29 which hides a coupling portion 201 of the first locking lever 20; a coupling portion 241 of the inside lever 24; the end of a motion-transmitting member 27 for transmitting an action of the inside handle IH as an interior opening handle of the door D; and the end of a motion-transmitting member 28 for transmitting an action of the locking knob LK as an interior locking member of the door D. The lid member 29 is open when each part is connected to the casing 11, and is closed after the motion-transmitting members 27, 28 are coupled to the coupling portion 201 of the first locking lever 20 and to the coupling portion 241 of the inside lever 24.

[0020] In FIGS. 4 to 7, at the upper part of the casing 11 and cover 12, there are attached a waterproof synthetic-rein cover 30 for preventing rainwater from coming into the casing 11, and a metal protector 31 made by plating stainless steel or general rustproof steel.

[0021] The casing 11 comprises a body-covering portion 117 covering a front surface, upper and lower surfaces and an exterior side surface with exposure of an interior side surface and a back surface; and a parts-holding portion 118 which is open toward the interior of the vehicle. The parts-holding portion 118 is provided approximately perpendicular to the interior end of the body-covering portion 117 and is greater in its height than the body-covering portion 117. Right above an upper wall 117a of the body-covering portion 117, an approximately cylindrical key-cylinder mounting portion which projects toward the exterior of the vehicle is formed at the top of the parts-holding portion 118.

[0022] The waterproof cover 30 is mounted over the parts-holding portion 118 of the casing 11 and the cover 12 and comprises an upper portion 301 covering a whole upper area of the parts-holding portion 118 and cover 12 and a vertical surface closer to the upper area; a rear portion 302 covering part of the parts-holding portion 118 higher than the upper wall 117a of the body-covering portion 117, a rear surface of the cover 12 and a vertical surface close to the rear surface; a front portion 303 covering the parts-holding portion 118, a front surface of the cover 12 and a vertical surface close to the front surface; and a triangular outer-side portion 304 connected to the upper portion 301 and the front portion 303 to obliquely cover an upper part of the parts-holding portion 118.

[0023] Projections 118a, liSa on the side of the parts-holding portion 118 are fitted in engagement holes 305, 305 of the outer side portion 304 of the waterproof cover 30, and the upper portion 301 is fixed to the cover 12 and protector 31 with a screw 32 (later described). Thus the waterproof cover 30 covers and holds an upper part of a bound portion S of the casing 11 and cover 12.

[0024] The protector 31 is mounted to the upper parts of the casing 11 and cover 12 over the upper portion 301, front portion 303 and outer-side portion 304 of the waterproof cover 30. The protector comprises an upper protection wall 311 which covers and protects the whole upper area of the parts-holding portion 118 of the casing 11 and the cover 12 and the upper bound portion S of the casing 11 and cover 12; a front protection wall 312 which suspends from the upper protection wall 311, and covers and protects most of an upper half of the front surfaces of the parts-holding portion 118 and cover 12 which do not face the inner surface Dl of the door D; and an outer protection wall 313 joined to the upper protection wall 311 and outer periphery of the front protection wall 312 which covers and protects an upper outer side of the parts-holding portion 118 which does not face the inner surface Dl of the door D. At the rear end of the upper protection wall 311, a key-cylinder mounting portion protection wall 314 which covers and protects an upper surface of the key-cylinder mounting portion 119 of the casing 11 projects toward the outside of the vehicle.

[0025] At the rear end of the outer protection wall 313 of the protector 31, an outer fixing portion 315 is formed to extend toward the outside of the vehicle, and a front inner fixing portion 316 extends backward at the upper part close to the inside of the vehicle of the front protection wall 312. An upper inner fixing portion 317 extends downward on the inner side of the upper protection wall 311.

[0026] In FIGS. Sand 7, an engagement hole 316a of the inner fixing portion 315 engages with a projection 121 on the side of the cover 12. The upper end of the outer fixing portion 315 is fixed to the front surface of the body-covering portion 117 of the casing 11 with a screw 32, so that the protector 31 is fixed over the upper parts of the casing 11 and cover 12 by holding the upper part of the waterproof cover 30 except the rear portion 302 of the waterproof cover 30. After the protector 31 is fixed, the upper part with the bound portion S of the casing 11 and cover 12 is covered with and protected by the protector 31, and the upper surface of the key-cylinder mounting portion 119 of the casing 11 is covered with and protected by the key-cylinder-mounting-portion protection wall 314. The upper inner fixing portion 317 is fixed with the screw 32, and the front surface of the upper covering portion 301 of the waterproof cover 30 is fixed to the upper end of the cover 12.

[0027] As mentioned above, in the door latch device in the foregoing embodiment, the upper and front surfaces with the bound portion S of the casing 11 and cover 12, the upper part of the outer side of the parts-holding portion 116 of the casing 11 and the upper surface of the key-cylinder mounting portion 119 are covered with and protected by the metal protector 31, thereby improving antitheft performance of the door latch device greatly.

Specifically, the metal protector 31 acts as a protection wall against a burglar to the door latch device. Thus, even if a special tool is put through an opening made by inserting the tool into a gap between an outer panel and a door glass of the door D and by breaking and pulling out the key cylinder and outside handle on the outer panel, it will become more difficult to force the bound portion open or to deform and break the upper parts of the casing 11, cover 12, key-cylinder mounting portion 119 and parts-holding portion 118.

Hence, it significantly becomes unlikely to open the door D by moving the operation mechanism 26 in the casing 11 with a tool in an unlocking direction, and the door latch device can meet the Thatcham Antitheft Performance Standards in UK.

[0028] The metal protector 31 is attached to cover the synthetic-resin waterproof cover 30 over the upper parts of the casing 11 and cover 12 which are covered with a double protection walls of the waterproof cover 30 and protector 31, thereby improving antitheft performance of the door latch device.

[0029] The foregoing relates to an embodiment of the present invention.

Various changes and modifications may be made without departing from the scope of claims.

[0030] (i) Without the waterproof cover 30, the protector 31 is only used.

(ii) The outer protection wall 313 of the protector 31 extends to the lower end of the parts-holding portion 118, and covers and protects the outer side of the parts-holding portion 118 more extensively.

(iii) The upper inner fixing portion 317 of the protector 31 extends to the lower end along the inner side of the cover 12 and cover the inner side of the cover 12 as inner side protection wall more broadly.

Claims

WHAT IS CLAIMED IS: 1. A vehicle door latch device comprising: a body fixed in an inner surface of a door and including an engagement mechanism that is engagable with a striker of a vehicle body; a casing mounted to the body and including an operation mechanism switchable between an unlocking state in which the engagement mechanism can disengage from the striker and a locking state in which the engagement mechanism cannot disengage from the striker in a parts-holding portion which has an opening toward an interior of a vehicle; a cover fixed to the casing and closing the opening of the parts-holding portion; and a metal protector having an upper protection wall covering an upper bound portion of the casing and the cover and its upper surface, the metal protector holding upper parts of the casing and the cover.
2. The vehicle door latch device of claim I wherein the protector has a front protection wall which suspends from the upper protecting wall, and covers and protects at least an upper part of front surfaces of the casing and the cover which do not face an inner surface of the door.
3. The vehicle door latch device of claim 1 or 2 wherein the protector comprises a key-cylinder-mounting-portion protection wall which is continuous with the upper protection wall, and covers and protects an upper surface of a key-cylinder mounting portion formed on an upper part of the parts-holding portion.
4. The vehicle door latch device of any one of claims I to 3 wherein the protector comprises an outer protection wall which covers and protects at least an upper part of an outer side of the part-holding portion which does not face of the inner surface of the door.
5. The vehicle door latch device of any one of claims 1 to 4 wherein a waterproof cover covers whole upper surfaces of the casing and the cover and a vertical surface close to the upper surface, the whole waterproof cover being covered with the protector.