Information
-
Patent Grant
-
6386599
-
Patent Number
6,386,599
-
Date Filed
Thursday, August 12, 199924 years ago
-
Date Issued
Tuesday, May 14, 200222 years ago
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Inventors
-
-
Examiners
Agents
- Stetina Brunda Garred & Brucker
-
CPC
-
US Classifications
Field of Search
US
- 292 201
- 292 216
- 049 280
-
International Classifications
-
Abstract
A latch arrangement for releasably retaining a striker, comprising a latch bolt shaped to retain the striker at a latching position, and to release the striker at an unlatching position of the latch bolt; a locking mechanism moveable between a locking position, at which it retains the latch bolt at its latching position, and an unlocking position, at which it allows the latch bolt to move to its unlatching position; means for linking the locking mechanism to a latch-opening external manual control such as a door handle; drive means coupled to the locking mechanism and/or the latch bolt for powered actuation thereof to latch or unlatch the locking mechanism and/or to drive the latch bolt to its latching position or to its unlatching position; a rotary clutch coupling the drive means to an electrical drive motor; and a clutch release mechanism drivingly coupled to the said external manual control such that operation of the latch-opening external manual control isolates the latch bolt and locking mechanism from the drive means.
Description
This invention relates to latch arrangements for closures such as automotive doors and tailgate locks, and is particularly, although not exclusively, useful with electronic central locking systems for vehicles. The inventions disclosed in this application concern components of the latches, systems incorporating such components, and methods of manufacture of latch arrangements. Generally, the purpose of each invention is to simplify and render more compact such latch arrangements, in order to reduce their cost and to reduce vehicle weight.
Electronic central locking systems are well known, and a typical such system is disclosed for example in GB-A-2167482; an improvement is disclosed in our PCT publication WO97/28338. These systems provide central control of the locking and unlocking of vehicle doors and other closures such as tailgates, bonnets and petrol caps, amongst other vehicle functions such as lights. They interact mechanically with the conventional locking mechanisms which usually comprise, for some doors, an external key mechanism and an internal door locking knob. Interior and exterior door handles are rendered inoperable or neutral by such locking mechanisms.
Vehicle door latches are disclosed for example in our own applications WO97/19242 entitled “Latch and Latch Actuator Arrangements”, WO97/19243 entitled “Latch Arrangement suitable for an Automobile Door” and WO97/28337 entitled “Latch Actuator Arrangement”. An electric motor incorporated within the latch, and usually controlled by the central locking arrangement, drives a mechanism for unlocking and locking the latch. A problem with door latches manufactured in accordance with other patent publications, such as EP-A-397966 (Roltra-Morese Spa) and GB-A-2221719 (Kiekert GmbH & Co Kommanditgesellschaft) has been size, weight and complexity.
Further, whilst mechanisms for using an electric motor to complete the closure of a partially-closed door are known as such, for example from U.S. Pat. No. 5423582 (Kiekert GmbH & Co Kommanditgesellschaft), and systems for using an electric motor to release the latch and allow the door to open are also known, for example from EP-A-625625 (General Motors Corporation) which discloses power-assisted door opening and closing, none of these prior systems has been hitherto capable of integration with electronic central locking. Some of the present inventions disclosed in this application provide integrated electric central locking and electric door opening and/or closing, and even the possibility of using a common electric motor for all these functions. This represents a substantial improvement to the state of the art.
To illustrate the possible saving in the number of latch components required to be assembled in manufacture, it can be seen for example from EP-A-743413 (Rockwell Light Vehicle Systems (UK) Limited) entitled “Vehicle Door Latch Assembly” that a very large number of components is typically required in a vehicle door latch. The present inventions reduce significantly the number of components, by simplifying the mechanical operation of the latch and its interaction with electric motor drive.
It is an important security feature that all electrically-operated drive systems, such as locking and door opening or closing, can be overridden by corresponding manual mechanical drive, as appropriate, in case of electrical malfunction or jamming. Each separate invention is capable of being used in a latch with full mechanical override.
Double locking or so-called deadlocking or “super locking” mechanisms for vehicle doors are known as such. If the door has been locked by the key mechanism or electronic central locking, then it cannot be unlocked by the interior door knob. It can be unlocked by the interior door knob only if it has previously been locked by the door knob. To achieve this efficiently and simple, an embodiment of the present invention provides an automoblie door latch having a deadlocking arrangement.
Existing door latches for vehicles generally include components within a housing, and components extending outside the housing which make the arrangement bulky. As shown for example in Kiekert U.S. Pat. No. 5419597, the levers which cause the latch to release and the door to open, and which are connected to door handles by cables, generally project from the latch housing. We have discovered that it is possible to simplify the latch arrangement and to accommodate door handle-operated levers inside the latch housing, by providing a common axis of rotation for the latching pawl (sometimes denoted by the general term “locking member”), the pawl release lever connected to the door handle, and preferably also a rotary coupling member for selectively coupling the pawl release lever to the pawl.
Door latches typically comprise housings to which components are permanently riveted, so that the door latch cannot be disassembly non-destructively. An embodiment of the present invention overcomes this problem, and also simplifies the process of assembly, by providing a latch assembly whose housing has a retaining means for retaining parallel plates releasably.
In some door latch arrangements incorporating electrically-powered actuation members for locking and unlocking, locking and unlocking is temporarily blocked if one of the door handles is pulled, but is unblocked once the handle is released. It then becomes necessary to repeat the actuation for locking or unlocking. In order to overcome this problem, an invention enables such actuation to be continued fully to completion once the handle has been released, without the need to repeat the actuation. To achieve this, the an embodiment of the present invention provides a latch arrangement.
In order to couple electric motor drive to various appropriate actuation members within the latch assembly, for door opening and/or closing and/or for locking and unlocking or other functions such as child-safety locking, we have discovered that a rotary indexing mechanism is particularly useful, in which there is resilient coupling between formations in the driving actuators and formations on the rotary indexing mechanism. The resilience of this coupling allows the continued rotation of the indexing mechanism past the actuator once actuation has been completed over a phase of rotation of the indexing mechanism, and prevents jamming. It also simplifies the mechanical arrangement, by allowing positional tolerance. Accordingly, an embodiment of the present invention provides a latch assembly.
Some existing door latch arrangements provide for so-called panic door opening, by which the door can be unlocked by the operation of the interior door handle without the need to lift the interior door knob. The door then remains unlocked to ensure that the door can be opened by the exterior door handle. This prevents inadvertent locking out of the vehicle by the occupant. Usually, the door latch will be unlocked when the vehicle is in motion, but there may be circumstances in which it is locked with the vehicle stationary or even moving. Another embodiment of the present invention enables panic door opening to be provided in a latch arrangement of compact and simple design.
A particularly important invention is the combination of electric locking and electric door latch release (door opening) using a common electric motor. The embodiment also provides electrically-powered door closing, using the same electric motor. Preferably also such latch arrangements provide selective electrical control of interior or exterior door handles, for example, for door opening, and preferably they also provide electrically-operable child-safety.
Latch arrangements typically comprise a latch bolt, for engaging a fixed striker in the door frame, and a latching pawl for releasably holding the latch bolt so as to latch the bolt. Electric door opening can then be achieved by actuating the latching pawl. We have discovered a particularly beneficial arrangement for electrical door latch release and door opening, using a linear actuator acting directly on the latch pawl, this arrangement allowing independent door opening by external mechanical means such as the door handle.
Another embodiment of the present invention provide an alternative beneficial arrangement for electrical door latch release on manual door opening, using a rotary actuator acting directly on the latch pawl.
Electrically-powered door closing requires application of the drive to the latch bolt which then pulls on the fixed striker to draw the door to its fully closed position. We have found that a particularly beneficial arrangement is to have a rotary actuator, under electric power, acting on the latch bolt. Preferably, the arrangement also provides door opening, i.e. the same electrical drive, and preferably the same rotary actuator, is used to release the latch pawl to allow the door to open.
As a beneficial alternative to the arrangement using a rotary actuator, an embodiment of the present invention also provides a linear actuator acting directly on the latch bolt, again with optional door opening.
With all of these arrangement, there is preferably a full mechanical override of any electrical function, i.e. mechanical actuation is independent.
With door latching arrangement there is a danger of inadvertent door locking when the door is slammed shut. This is particularly disadvantageous in electric central locking arrangements in which the locking of one door is linked to the locking of all doors. Existing anti-slam locking arrangements are generally quite complex, and the purpose of an embodiment of the present invention is to provide an anti-slam latching arrangement with all the advantages of compactness and simplicity of the other inventions. This is achieved by appropriately orientating a reciprocating sliding coupling member within the latch arrangement. Accordingly to the an embodiment of the present invention, anti-slam latching is latching is achieved differently, by ensuring that an actuator is prevented from moving within the latching arrangement whenever the arrangement is unlatched and the door open. The latching arrangement has a fixed formation which co-operates with the coupling actuator only at its unlocking configuration.
In order that the inventions may be better understood, the preferred embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, in which common reference numerals are intended to denote identical or equivalent parts throughout.
FIG. 1
shows an electric door opening mechanism;
FIG. 2
shows an alternative electrical door opening mechanism;
FIG. 3
shows an electrical door opening and closing mechanism;
FIG. 4
shows an electrical door opening and closing mechanism;
FIG. 5
shows a further electrical door opening and closing mechanism;
FIG. 6
shows a variant of the electrical door opening and closing mechanism of
FIG. 5
;
FIG. 7
shows an electrical door opening mechanism, as a variant of
FIG. 2
;
FIG. 8
shows an electrical door opening and closing arrangement as a variant of
FIG. 5
;
FIG. 9
shows a further electrical door opening and closing mechanism;
FIG. 10
shows a further electrical door opening and closing mechanism, using a rotary indexing and driving mechanism;
FIG. 10
a
shows a door opening arrangement integrated with electrical locking;
FIG. 10
b
shows an electrical door opening and closing mechanism, using a bi-directional rotary driving and indexing arrangement;
FIG. 11
shows a latch arrangement with a rotary driving and indexing mechanism for electrical door opening and closing, also enabling powered door opening;
FIG. 12
is a partial view of two of the components of
FIG. 11
;
FIG. 13
is a simplified view of two of the components of
FIG. 11
, but in which the motor gearing is modified;
FIG. 14
shows an electrical door opening and closing mechanism, as a variant of
FIG. 8
;
FIG. 15
shows a further door opening arrangement;
FIG. 16
shows a compact latch arrangement within a housing suitable for vehicle doors, with electric locking;
FIG. 17
shows a latch arrangement for the selective electrical locking of a door with two door handle mechanisms and an interior door knob;
FIG. 18
shows a variation of the latch arrangement of
FIG. 17
;
FIG. 18A
is a schematic partial enlarged end view from the right of the arrangement of
FIG. 18
;
FIG. 19
shows a door handle lever of the type shown in
FIGS. 17 and 18
and illustrates how the actuation of the mechanism towards its unlocked, handling-coupling position is continued automatically even after it has been blocked temporarily by the door handle being actuated;
FIG. 20
illustrates an alternative form of rotary coupling member for the arrangements shown in
FIGS. 17 and 18
;
FIG. 21
shows an integrated electrical door opening and closing, and central locking arrangement, using a common electrical motor;
FIG. 22
shows the use of a rotary indexing and driving mechanism for three separate actuation functions in a latching arrangement;
FIG. 23
shows a variation of the arrangement of
FIG. 22
, for four independent actuation mechanisms;
FIG. 24
shows the use of a rotary indexing and driving mechanism for the independent actuation of locking and door opening, suitable speciality for use with a tailgate or boot latch;
FIG. 25
shows the use of a rotary indexing and driving mechanism for driving two linear actuators selectively, for example those shown in
FIGS. 17 and 18
;
FIG. 26
illustrates a possible form of resilient coupling between an actuation member and a rotary drive member, useful for example in the arrangement of
FIG. 17
;
FIG. 27
shows part of a latch arrangement of the type shown in the other drawings, with a single housing which is disassemblable non-destructively;
MOTOR VEHICHLE WITH CENTRAL LOCKING
Electrical Door Opening and/or Closing
The operation of the latch bolt and pawl in relation to the movement of the door is described below with reference to
FIGS. 11
to
13
, and also in the published patent specifications referred to above.
As shown in
FIG. 1
, a latch bolt
11
, closeable around a striker
10
, has notches
13
and
14
respectively for full-latch and half-latch detention of the pawl
20
. The latch bolt
11
is spring biased clockwise to the open position, and the pawl
20
is spring biased anti-clockwise (B
5
) to the latching position at which the latch bolt is latched. An electric motor
70
has a rotary output with crown and bevel gearing to a rotary output drive
50
which is arranged to rotate in the direction D
1
so that its eccentrically-located projecting pin
30
abuts against the pawl
20
to move it in direction D
2
to its unlatching position. Upon continued rotation in direction D
1
, the pin
30
allows the pawl
20
to spring back in direction D
5
, to latch the latch bolt once again after the door has been closed.
The pin
30
is returned to its original neutral position Np, as shown in
FIG. 1
, either by the force of the pawl
20
returning to its latching position, or else under the reverse drive of the electric motor
70
. It is then ready, in its neutral position, for a further door-opening actuation.
Obviously alternative output drive couplings are possible, for example screw gears or spur gears. Further, the pin
30
could be replaced with any form of cam arrangement for abutting against a pawl.
In this arrangement, the door is opened, once the pawl has moved to its unlatching position, under the force of the resiliently-deformed door seal. The spring bias of the latch bolt
11
also contributes to the opening of the door.
An alternative form of door opening arrangement is shown in FIG.
2
. The electric motor
70
output drive takes the form of a rack and pinion arrangement
31
producing linear drive in the direction D
1
, with part of the rack abutting against the pawl
20
. Once the latch bolt has been electrically sensed to have moved to its fully unlatched position, the electric motor is either switched off, or else powered in the reverse direction, to bring the rack
31
back to its neutral position as shown in FIG.
2
. When it is switched off, the rack remains in its door-opening position until the door is shut. Shutting the door causes the pawl to rotate to its latch engaging position, simultaneously driving the rack back to its neutral position. This is assisted by the spring biasing of the pawl
20
.
The sensing of the position of the latch bolt also of course applies to the arrangement of
FIG. 1
, for either switching off or reverse powering of the electric motor.
The arrangements of
FIGS. 1 and 2
are suitable for vehicle side doors. Tailgate and boot latch bolts differ from that illustrated, in that they normally have only one notch
13
, for fully latching the bolt. Again, various alternative gearing arrangements would of course be possible.
The latch arrangement shown in
FIG. 3
provides for powered door closing as well as electric door opening. Thus it is an opening and closing mechanism, powered by the same electric motor
70
. The electric motor drives a rotary indexing and driving member
50
selectively in either direction, D
1
or D
4
. Its neutral position Np, shown in
FIG. 3
, corresponds to the position at which its pin
34
is free of the door latch
11
. The indexing and driving member
50
is rotationally biased towards its neutral position by a torsion spring
36
mounted co-axially with the member
50
, and constrained by a bar
35
fixed to the latch housing. The torsion spring
36
has two limbs
33
a
and
33
b
which engage opposite side surfaces of the projecting pin
34
. Thus as the member
50
is driven clockwise in direction D
1
, pin
34
drives limb
33
a
of the spring which then causes the member
50
to return in the opposite direction to the neutral position. Correspondingly, anti-clockwise movement D
4
causes pin
34
to displace limb
33
b
of the spring, which again returns the member
50
.
In this example, the unlatching or release of the pawl
20
is achieved indirectly through an actuation plate
39
pivotally connected at
40
to the pawl
20
, and coupled to the rotary indexing and driving mechanism
50
by means of an arcuate slot
39
and a projecting pin
32
of the member
50
. The arcuate slot
39
of the actuation plate
38
is concentric with the rotary member
50
, and its function is to allow relative rotation of the rotary member
50
for approximately 70° in the clockwise direction D
1
, for door closing, without interference.
An extension arm
37
of the latch bolt
11
projects over the rotary indexing and driving member
50
for selective engagement with the pin
34
. To close the door, the pin
34
is driven clockwise in direction D
1
to the position A which the latch bolt
11
will have reached as a result of partial closure of the door manually. Completion of door closing is achieved by pin
34
abutting against extension
37
and driving it in the direction D
3
to its fully latched position B. Once the latch bolt is electrically sensed to be fully latched, the motor is switched off and the rotary member
50
is returned by the spring
36
to its neutral position Np.
To open the door electrically, the motor drives the pin
34
anti-clockwise in direction D
4
, causing the pin
32
immediately to pull the end of the slot
39
, thus to pull the pawl
20
in the direction D
5
to unlatch it in direction D
6
. The latch bolt then springs open in the direction D
7
as the door moves away from the frame in direction D
8
. Once the latch bolt has electrically been sensed to have reached its fully unlatched position, the motor is switched off, and rotary member
50
springs back to its neutral position Np.
The electrical position sensors are placed suitably in the latch so that, for example, when the pawl
20
is actuated to its unlatching position, it is prevented from falling into its hal-flatched position in notch
14
.
This arrangement is capable of being accommodated in a single housing which is compact and simple to produce, improving on sound proofing and reducing manufacturing costs.
The latch arrangement of
FIG. 4
is a variant of that of
FIG. 3
, for door opening and closing. In this example, the actuator place
41
, which replaces plate
38
, is arranged to slide over the pivot axis
43
of the rotary indexing and driving member
50
; it has a slot
45
which guides it over the pivot
43
. The actuation place
41
has an end flange
44
A depending downwardly for abutting engagement with the pin
34
of the rotary member
50
. The actuator plate
41
is capable of sliding between positions C and C
1
, corresponding tot he latched and unlatched positions respectively of the pawl
20
.
Door closing is caused by rotating the pin
34
clockwise in direction D
3
to abut against the latch bolt extension
37
at A and drive it to position A
1
. After a slight overtravel beyond point A
1
, the cam pin
34
becomes free from the latch bolt whilst rotating in the direction D
3
towards a second neutral position Np
2
. Thus the first neutral position Np
1
is located just before the cam pin
34
engages the latch bolt extension
37
. The second neutral position Np
2
is located at a point just past A
1
but before it can engage the flange
44
A. Once freed from the latch bolt, the cam pin
34
stops at its second neutral position Np
2
, by a resiliently deformable means such as a spring (not shown), after the motor has been switched off under the control of a suitable electrical position sensor (not shown). The motor may also be stopped at the second neutral position by means of a controlled powering of the motor in the reverse direction.
To open the door electrically the motor is powered to drive the cam pin from its neutral position
34
B in direction D
3
to the point
34
C at which it abuts the actuator plate
41
to the point C
1
at which the flange reaches the positions
44
B in direction D
7
. This causes the pawl to rotate in direction D
4
to its fully unlatched position which allows the latch bolt to rotate in direction D
5
whilst simultaneously moving away from the striker in direction D
6
. The cam pin
34
continues in the same direction to its first neutral point Np
1
.
At either neutral position, the latch bolt and pawl are completely free to be actuated manually, in a conventional manner, between their latched and unlatched positions. Thus conventional mechanical operation is interrupted only during electrical door opening and closing. This provides complete mechanical override as a safety measure against electrical dysfunction.
In contrast to the arrangement of
FIG. 3
, the rotary indexing and driving member
50
rotates uni-directionally, although its motion may be braked or partially reversed by reversed electrical drive.
The arrangement of
FIG. 4
has the advantages of compactness and sound proofing associated with the arrangement of FIG.
3
.
A variant is shown in
FIG. 5
, providing electrical door opening and closing using the same electrical drive motor
70
. In this example, the rotary output drive at
50
is converted to linear motion by a rack and pinion gear. The rack
56
is formed integrally with a shuttle which has an end abutment surface
55
for engaging the latch bolt extension
37
. At the other end, the rack is connected at
57
to a coil spring
58
mounted on the frame
59
of the latch housing, for compression and tension. The spring serves to return the shuttle to a neutral position Np and also to absorb shock and reduce noise.
The shuttle
56
is connected drivingly to an actuator plate
52
by a pin
54
riding in a slot
53
, such that the shuttle is capable of driving the latch bolt for door closing without interference. The actuator plate
52
is pivotally connected at
51
to the pawl
20
.
As with the arrangements of
FIGS. 3 and 4
, the electric drive mechanism is isolated from the conventional mechanical latch operation, by which a door handle operates the pawl, when it is at its neutral position Np.
Thus to open the door the shuttle
56
is driven from its neutral position to its extreme position P
1
in direction D
3
, after which the electric motor is switched off and its returns to its neutral position. Electrical door opening is achieved by driving the shuttle in the opposite direction D
5
, from the neutral position to the second extreme position P
2
, which pulls the actuation plate
52
and releases the pawl.
This arrangement uses a potentially smaller drive motor, due to the greater gearing ration.
A further modification of the door opening and closing mechanism is shown in FIG.
6
. Instead of the rack and pinion arrangement, a linear shuttle
71
is driven in either linear direction by the cam pin
34
of the rotary indexing and driving member
50
, in direction D
1
or D
2
as the case may be. The cam pin
34
rides against a cam
74
fixed to the shuttle
71
, so that drive is effected over a limited angular range or phase, for example about 40°, of rotation of the rotary member
50
. Once again, the shuttle
71
is biased towards its neutral position by a tension-compression spring
72
mounted to a frame
73
. The shuttle has an end formation
78
which drivingly abuts against the latch bolt extension
37
to move it from position A to position B. For electrical door opening, an actuator plate
77
corresponding to plate
52
is provided to link the shuttle
71
with the pawl
20
. As with the arrangement of
FIG. 5
, a pin
75
on the shuttle slides within a groove
76
of the actuator place
77
.
The arrangement of
FIG. 6
has the additional advantage of adaptability, and it provides for an easier movement of the drive gear to its neutral position in the event that electric actuation is prematurely interrupted.
An alternative arrangement for electrical door opening is shown in FIG.
7
. In this example, the shuttle
83
, which is again constrained to move linearly, is driven from the electric motor
70
by means of leadscrew gearing taking the form of screw
81
and internally-threaded nut
82
. The leadscrew
81
is driven by bevel gearing
80
from the rotary output drive. Once again, the shuttle is spring biased to its neutral position by a tension-compression spring
86
. The slot
84
which couples to the pin
85
of the pawl
20
gives sufficient freedom to allow for independent mechanical door opening, as before. In this example, there is no provision for door closing, although of course this arrangement could be incorporated in the door closing arrangements of
FIGS. 4 and 5
for example. The arrangement is simplified, and provides for just one neutral position A and one actuated position B of the shuttle
83
.
This arrangement has the further advantage of complete independence of the mechanical door opening and closing from the electrical arrangement, at all stages of electrical door opening. It also has the advantages of enabling use with a relatively small motor, due to the high gearing ratio, and is extremely adaptable and simple. As before, the compression-tension spring provides an anti-backlash arrangement which reduces noise by absorbing the inertia of the mechanism after the motor has been switched off; this also prolongs the life of the drive mechanism.
A further variation of the door opening and closing mechanism is shown in FIG.
8
. The shuttle
95
in this example is driven linearly by a leadscrew
96
between two spaced tension springs
97
and
98
which are mounted on the leadscrew
96
between fixed brackets
99
and
200
. The leadscrew is driven by a bevel gear
80
powered by the motor
70
. The actuator plate
91
is again coupled to the shuttle
95
by a pin
92
sliding in a slot
94
, and the shuttle
95
has an abutment surface at its end
93
A which moves between a neutral position
93
B, position A, a lower position
93
C, position C, at which pawl is unlatched, and an upper extreme position
93
A, position B, at which the latch bolt is completely closed.
Preferably, the nut
95
, formed integrally with the shuttle, and the screw
96
, have their meshing teeth cut at 45° in relation to the axis of rotation of the leadscrew
96
, so that the shuttle can drive the leadscrew and vice-versa. The means for constraining the nut
95
to move linearly may take any suitable form, such as grooves and rails (not shown) fixed to, or integral with, the latch housing (not shown).
The springs
97
,
98
may be replaced by a single spring capable of use as a compression or tension spring coupled to the nut
95
. It may also be a torsion spring coupled to the drive gear.
As with previous arrangements, electrical position sensing is employed to control the powering of the electric motor. A current sensor may be incorporated with the control electronics as an indicator that the latch bolt, for example has reached its latching position, since only overtravel beyond that point raises the current. Again, polarity of the electrical drive may temporarily be revered, to counteract the inertia of the moving components.
This arrangement has advantages corresponding to the advantages of the arrangement of
FIGS. 6 and 7
.
With any of the arrangements of
FIGS. 1
to
8
, a clutch mechanism may be provided in the rotary output drive of the electric motor
70
. A conventional centrifugal clutch is preferred. This would eliminate any inductive current generated in the motor when it is driven by the mechanical components. It also helps to reduce the load on the return springs which are used for bringing the mechanism back to its neutral position after motorized actuation.
A further modification of the previously-described electrical door opening and closing latch arrangements is shown in FIG.
9
. In this example, the actuator plate
202
is connected pivotally at
203
to the pawl
20
near to the point of engagement with the latch bolt
11
. It therefore operates in the reverse direction, as there is no lever action. This actuator plate
202
is constrained to rotate about the pivot axis of the rotary indexing and driving mechanism
50
, or to move linearly in the actuation direction D
4
, by virtue of an end fork with limbs
205
and
206
on either side of the pivot axis.
In this example, the cam pin
34
is replaced by an arrangement of radial cams all integral with the rotary mechanism
50
and arranged in two separate planes normal to the pivot axis. In a first plane, radial cam
207
is arranged selectively to abut and drive the latch bolt extension
37
. In a separate plane, radial cams
209
and
208
, spaced by approximately 100°, respectively engage a depending lug
204
of the actuation plate
202
of the door opening, and a W-shaped leaf spring
210
fixed to the latch housing. The W-shaped spring
210
is a shock-absorber for the cam
208
as it rides up either limb, and locates it centrally. The spring
210
prevents backlash as well as locating the arrangement in its neutral position as shown.
To close the door, the rotary member
50
is driven clockwise in direction D
1
to drive cam
207
against the latch bolt extension
37
, as previously described. To open th door electrically, the rotary member
50
is also driven in direction D
1
from its neutral position, to engage the lug
204
to drive the actuator plate
202
in direction D
4
to unlatch the pawl.
Should electrical actuation be interrupted for whatever reason, the drive gear is moved back to its neutral position by means of a sliding spring (not shown) coupled to the drive gear. This guarantees full mechanical override, in the case of electrical malfunction.
The latch arrangement of
FIG. 10
importantly illustrates the use of one electric motor
70
, and one rotary indexing and driving mechanism
50
, to control independently the door opening and closing mechanism on the one hand, and electric locking, on the other hand. The door opening and closing mechanism involves a shuttle
215
constrained to move linearly, and coupled to a tension-compression spring
218
, as previously described in relation to FIG.
6
. The rotary member
50
has a single cam pin
34
which is rotatable in either direction D
1
, D
5
between two neutral positions Np
1
and Np
2
, at which it is retained respectively by W-shaped fixed springs
220
and
219
. An actuation member
222
is constrained to move linearly in either direction D
11
, D
12
between positions C
1
and C
2
, and it has the toggle lever
221
at its end for engagement with the cam pin
34
. The toggle lever
221
may be of the type illustrated and described below with reference to FIG.
35
. It is mounted pivotally at the end of the actuation member
222
and biased by a torsion spring
223
to its neutral position normal to the length of the actuation member. This arrangement enables enables the cam pin
34
to abut driving against the toggle
221
to drive the actuation member
222
in direction D
11
, but then to release it as it is resiliently deformed against the spring torsion, to enable the cam pin
34
to continue its rotary movement. In this example, it is capable of being driven in either direction by the cam pin
34
.
As with W-shaped spring
210
of
FIG. 9
, the springs
219
,
220
have the function of absorbing rotary impact, as the pin rides up against the external limb of the spring form either direction. The cam pin then moves on to settle between the two outer lims of the pin in the central recess. This prevents accidental overrunning.
Electrical door locking and unlocking, using the actuation member
222
, is described below in greater detail with reference to
FIGS. 16
,
18
,
21
-
38
26
. Briefly, it interacts with a key mechanism and selectively unlocks the pawl
20
to prevent or allow actuation of door handles or the like being transmitted to the pawl.
A variation of the door opening mechanism of
FIG. 2
, which also provides for electric locking and unlocking under the control of the same electric motor
70
, is shown in FIG.
10
A. In this example, a rack and pinion arrangement integral with a linear shuttle drives the pawl
20
by means of an abutment surface
231
. The pawl
20
has an extension lever
232
which is driven either by the abutment surface
231
, or else by a cable or other link to the latch locking mechanism (not shown). A tension-compression spring
235
again biases the shuttle towards a neutral position N.
For electric locking, the notch
234
in the shuttle selectively engages with the end
1814
of a lever on
1810
pivoted at its center
1812
, and spring biased by a torsion spring
1813
on the pivot axis
1812
towards the neutral position as shown. The opposite limb
1811
engages in a notch of an actuation member
300
capable of moving in either direction D
7
, for locking and unlocking the latch.
FIG. 10B
shows a further arrangement for door opening and closing, which is analogous to the arrangement described below with reference to FIG.
24
. The rotary member
50
acts directly on the pawl
20
, which has an extension arm
20
A, and on the latch bolt extension
37
. The cam pin
30
is biased by spring
1802
, located around fixed lock
1801
, to its neutral position N.
Door closing is effected by driving the cam pin
30
against the extension
37
at the position A towards B; it is then impelled back to its neutral position N by the spring. Driving the motor in the reverse direction, the cam pin
30
moves in direction D
2
to abut against the pawl
20
A to release the latch bolt. Again, the cam pin
30
can be returned to its neutral position, either electrically or by the return spring.
The pawl
20
can alternatively be released manually by externally operable means, such as the handle through a lever
246
and cable
245
.
In this example, the distal end
20
A of the pawl
20
is elevated by bending so that it can override the latch bolt extension
37
.
This particular arrangement enables a reduction in the drive torque and renders it more adaptable.
Door Opening and/or Closing Under Electric Power
The arrangement of
FIGS. 11-13
provides electric door opening by which the pawl is first released and then the latch bolt is driven under electric power to ensure that it opens fully. The arrangement also provides for powered door closing, as with arrangement described above.
With reference first to
FIGS. 11
to
13
of the drawings, a vehicle door closure arrangement comprises a striker
10
connected to the door frame of a vehicle, and a latch bolt
11
forming part of a latch arrangement supported on the edge of the vehicle door. Whilst the shape fo the latch bolt
11
in
FIG. 11
is special to the present invention, its general function is conventional and need not b described in detail here. The latch bolt
11
is mounted pivotally at
15
for rotary motion as shown by arrow
18
, driven by the relative motion
17
of the striker
10
in a U-shaped notch
12
formed in the latch bolt
11
. The latch bolt
11
has two further notches
13
,
14
formed in its periphery, for engagement with a locking pawl
20
. Notch
13
is for locking the latch bolt at a latching rotary position, which retains the striker
10
and maintains closed the vehicle door. The door is capable of being opened by releasing the pawl
20
from its locking position in notch
13
, allowing the striker
10
to drive the latch bolt
11
clockwise
18
under the camming action of the indentation
12
, until it is no longer detained by the striker
10
. However, if the locking pawl
20
is allowed to engage the further notch
14
, at a so-called half latch position, then the door can be half latched, partially open.
The locking pawl
20
is mounted pivotally at
21
, and pivot points
15
and
21
are both fixed to a latch housing (not shown). The pawl
20
has an end tooth
24
for locking engagement in notches
13
,
14
. At the same end, it is formed with a pin
23
on which there is pivotally mounted a link arm
25
which is coupled to a door handle for actuating the paw
1
. Lifting the door handle causes the link arm
25
to move in the direction shown by arrow
26
, pulling the pawl
20
anticlockwise as shown by arrow
22
, and moving the pawl to its unlocking position (not shown).
In accordance with the present invention, the latch bolt
11
is coupled drivingly to an electric drive motor
70
, of the type commonly used for the central locking of vehicle doors. This coupling arrangement, to be described in greater detail below, also incorporates an arrangement for releasing the pawl.
The motor
70
is coupled to the latch bolt
11
through gears
40
,
50
,
60
. Gear
40
, shown in isolation in
FIG. 20
, meshes at
45
with teeth
16
on the latch bolt
11
. It is mounted for rotation about axis
42
, which is shared by the larger-diameter gear
50
, shown in isolation in FIG.
21
. Gear
50
is drivingly coupled to gear
40
, with 60 degrees of rotary free play, by means of a pair of slots
52
,
53
in one of the plates of gear
50
, through which slots project a pair of driving pins
44
,
43
connected to gear
40
. This 60° free play is important, in this embodiment, to allow for proper sequencing of the pawl release and latch bolt drive.
Rotary motion of gear
50
in the direction shown by arrow
41
is controlled by its direct meshing engagement with the spindle of the motor
70
. In the embodiments shown in
FIG. 11
, this coupling is through the meshing of gear
71
on the motor spindle and teeth
62
on crown gear
60
, gear
60
being connected to a smaller-diameter gear
61
which drives teeth
54
on gear
60
. In the alternative embodiment shown in
FIG. 13
, worm gear
72
is driven directly by the motor spindle, and drives gear
50
directly.
One section of gear
50
has a U-shaped indentation
51
which cams against a limb
33
projecting from a hook
32
at the end of a pawl actuator
30
. The actuator
30
is constrained by formations on the latch housing (not shown) to reciprocate generally in the direction shown by arrow
34
in
FIG. 11
, so as to link mechanically with pin
23
of the pawl
20
. The upper end of the pawl actuator
30
is shaped as a dog leg with an extension formed with a slot which surrounds the pin
23
. This arrangement provides free play in the driving connection between the pawl actuator
30
and pawl
20
.
The operation of the power-assisted door latch will now be described. It will be appreciated that the door latch can be operated either mechanically, without motor power, or else under motor power. This of course is an important safety feature.
Powered operation will be described first. With the door in its closed position, as shown in
FIG. 11
, the latch bolt
11
is at its latching position, and the locking pawl
20
at its locking position. Pawl actuator
30
is engaged by the gear
50
. Upon receipt of a command to open the door, from the central electronic control circuit
90
, the motor
70
drives the gear
50
anticlockwise as shown at
41
. For the first 60° of rotation, the gear
40
will remain stationary, and no attempt is made to rotate the latch bolt
11
. Otherwise, the latch and pawl would jam. The indentation
51
pushes the pawl actuator
30
in the direction of arrow
34
, and this immediately pushes against pin
23
and drives the pawl anticlockwise as shown by arrow
22
, to move it to its unlocking position. Continued rotation of gear
50
cams out the extension
33
of the pawl actuator
30
, so that it rests on the outer periphery of gear
50
, and is temporarily prevented from re-entering. Continued rotation past the first 60° causes the walls of slots
52
,
53
to engage the pins
44
,
43
of the smaller gear
40
, which drives the latch bolt
11
in the direction shown by arrow
18
. With powered operation in this way, half latching is deliberately prevented. Thus the latch bolt is rotated so that notch
14
passes tooth
24
, and until the outer surface of latch bolt
11
engages tooth
24
the pawl
20
, preventing re-entry of the pawl.
Electronic position sensors, to be described below, cause the motor drive to switch off at the point that the vehicle door is partially open, and has passed its unlatched position. The door can then conveniently be opened fully by the passenger or driver.
Driving the latch bolt
11
clockwise has the desirable effect of pushing the door open, by reacting against the striker
10
. This accelerates opening movement of the door, and such opening movement will continue until it is decelerated by friction in the door hinges, by an amount dependent on the inclination of the vehicle.
When the door is closed, it will reach the same position, just beyond the half latch position, and will then cause the electric motor to be switched on again, with reverse polarity (to be described below). The motor then provides power-assisted door closing, to ensure that the door is properly closed and latched. Again, the half latch position is not possible, with power assisted closing. As the door commences full closure, anticlockwise rotation of the latch bolt
11
accompanies clockwise rotation of the smaller gear
40
together with the larger gear
50
. After the first phase of such rotation, the extension
33
of the pawl actuator
30
translates back downwards. The free play between the pawl actuator and the pawl
20
allows the pawl
20
to ride over the slot
14
and into the slot
13
, under a clockwise spring bias (not shown), without jamming. As the tooth
24
lodges in the slot
13
, the arrangement returns to the position shown in FIG.
19
.
Without power assist, the latch can be controlled by the door handle through the link arm
25
. The mechanical interactions remain, and opening and closing the door causes rotation of th motor spindle, but this simply provides a small amount of mechanical resistance. Lifting the link arm
25
releases the pawl, allowing the door to be opened, whereby the latch bolt
11
is turned clockwise by the striker
10
. Again, the pawl actuator
30
is release from engagement with the gear
50
until the door is reclosed. It will also be appreciated that since the mechanical sequence is the same, power assisted closing can follow non power assisted opening, and vice versa. When the latch is operated purely mechanically, it is capable of lodging in the half latch position, with tooth
24
of pawl
20
in notch
14
. This is an additional convenience and safety feature.
A modification of the arrangement of
FIGS. 2 and 10A
, which provides door opening and closing, is shown in FIG.
14
. As will be apparent, the abutment surface
231
on the shuttle
233
drives the pawl by way of its extension arm
232
, moving it to position
232
A. Continued motion in the same direction drives the latch bolt extension
37
to its unlatched position
37
A. As with the arrangement of
FIG. 10A
, the notch
234
engages a link lever (
1810
FIGS. 10A
) for electrical locking and unlocking.
An electric opening mechanism especially suitable for a boot or tailgate latch is shown in FIG.
15
. The rotary output drive
50
of the motor
70
is coupled rigidly with a leadscrew
240
which causes linear reciprocating movement of a shuttle block
242
which is internally threaded in a nut portion
243
and which has an internal bore to receive the leadscrew
240
. An end abutment surface of the shuttle
242
engages and drives the pawl
20
for door opening. As with other arrangements, a portion
244
of the pawl is connected by a link
245
to an external manual control such as a handle through a lever
246
, to enable the door to be opened provided first the latch has been unlocked by a key mechanism, an interior door knob or an electrical control (not shown). The nut
243
and shuttle returns after each actuation to its neutral position, as shown, by at least one of the following mechanisms: a return spring acting on the nut; a return nut acting on the pawl; and repowering the motor so as to cause the nut to move in direction D
6
. The nut
243
is constrained to move linearly, by suitable means such as rails fixed to the housing.
In an alternative arrangement, the leadscrew
240
meshes with an internal thread
241
in the rotary drive gear
50
, and the leadscrew is formed integrally with the shuttle
242
. Further mechanical equivalent configurations will occur to the skilled reader.
A compact door latch arrangement is shown in FIG.
16
. The housing
250
is in the form of a flat rectangular box with a rounded corner and a U-shaped opening for receiving the striker
10
. The housing comprises mutually opposed end plates
252
and a side wall
251
defining an internal compartment
253
for housing the electric motor
70
and rotary output gearing
50
. Cables
256
,
258
for controlling respective levers
255
and
257
project through the side wall and are connected to the levers by nipples held within end formations.
It is especially important for the compactness of this arrangement that several components are all mounted on the same pivot axis
21
, including the pawl
20
. This latch arrangement provides electric locking and unlocking.
The pawl
20
has a lever arm formed with a fork
259
to enable it to be driven rotationally. A pawl release lever
255
is pivotally connected on the pawl axis
21
, for actuation by an external manual controls such as an interior or exterior door handle. Rotary motion of the pawl release lever
255
is transmitted to the pawl fork
259
only by means of a rotary coupling member
300
,
400
which carries a dependent elongate lug
262
disposed parallel to the pivot axis. Clockwise actuation of the pawl release lever
255
cause its end notch
263
to engage the lug
262
, which is then driven against the fork
259
. This leads the pawl
20
to its unlatching position, to allow the door to open.
The rotary coupling member
300
,
400
comprises two components connected pivotally at the pivot axis
21
but capable of sliding movement, normal to the pivot axis, by virtue of an oval slot formed in both components
300
,
400
. Locking member
300
is constrained to move linearly between the left-most position as shown in
FIG. 16
, at which the door is unlocked, and a right-most position at which the door locked because the pawl release lever
225
is no longer coupled to the pawl
20
, i.e. it is rendered neutral. A rotary sliding member
400
has an arcuate slot which rides over the pin
301
on the locking member
300
, and is integrally formed with the dependent lug
262
. The slot is sufficient to allow the rotary sliding member to rotate with the pawl release lever
255
when they are coupled by virtue of the lug
262
. When the locking member
300
is moved rightwards to its locking position at which it neutralises the pawl release lever, the lug
262
is moved with it, so that it can no longer be engaged by the notch
263
fo the pawl release lever.
The rotary coupling member
300
,
400
, is driven selectively by an output disc
500
with an eccentric pin, driven by the bevel gear
50
of the motor
70
. The pin drives the locking member
300
through a notch or other formation
302
. Such coupling arrangements will be described in greater detail, in various alternative forms, with reference to
FIGS. 17
,
18
, AND
26
.
Mechanical locking and unlocking is achieved through lever
257
, for example from a key mechanism or interior door knob. This drives the locking member
300
and forces the electric motor drive when it is not powered. Thus the latch arrangement provides independent mechanical and electric locking and unlocking.
A member
254
, of which only a portion is shown, also couples drivingly with part of the locking member
300
, for locking and unlocking.
The rotary sliding member
400
with the lug
262
, which is permanently coupled with the fork
259
of the pawl
20
, is prevented from moving between its locking and unlocking positions for as long as it is in the course fo being actuated rotationally, by means of a boss or elongate block
260
projecting from the housing. Whilst the fork
259
rides over the boss
260
, the lug
262
cannot move radially of the pivot axis
21
past the boss
260
, in either radially direction.
Anti-slam Locking
The boss
260
also has the desirable function of providing anti-slam locking of the latch. The boss
260
prevents inadvertent locking of the door whilst the door handle is held open and the pawl is in its unlatching position, by preventing sliding movement of the locking member
300
, due to the radial engagement of lug
262
with boss
260
. Thus if the door latch were unlocked and the door then slammed shut, the door could not inadvertently be locked, since the rotary coupling member
300
,
400
is held within the housing.
Even without such locking arrangement with the boss
260
, the latch arrangement can be configured for anti-slam locking. In the configuration shown in
FIG. 16
, and also in the arrangement of
FIGS. 17 and 18
, the locked position of the locking member
300
is to the right-hand side, away from the striker
10
. The orientation of the latch bolt is such that the door closes in the leftwards direction. Thus, if the latch is unlocked before door closing, the locking member
300
will be fully to the left, and any impact upon slamming the door will have no effect on its position. If however the door is locked and the door is then slammed, the locking member
300
may be forced, under the impact, to continue its motion leftwards to the unlocking position, and it may rebound to its locking position, but either way there would be no inadvertent movement from an unlocking to a locking position. Thus, the orientation of the latch bolt and the path of the coupling member
300
are such that, in use, the locking position is substantially further than the unlocking position of the coupling member
300
from the striker
10
.
Selective Electric Locking
Two alternative latch arrangement for electrical locking and unlocking will be described with reference to
FIGS. 17 and 18
. Each arrangement has two pawl release levers
700
,
800
for connection to external manual controls such as interior and exterior door handles, and each corresponding generally to the pawl release lever
255
described above with reference to FIG.
16
. Each pawl release lever is selectively coupled to the pawl
20
by its own rotary coupling member
300
,
400
and
350
,
450
respectively. Each such rotary coupling member comprises a locking member
300
.
350
connected respectively to a rotary sliding member
400
,
450
which have analogous functions to the corresponding components described above with reference to FIG.
16
. They are all disposed around the common pivot axis
21
, providing maximum compactness and simplicity, and enabling the pawl release levers to have sufficient leverage over the pawl to be accommodated within the housing.
In addition, each latch arrangement has a further lever
900
connected to an external control mechanism through a cable
901
, such as to a child-safety switch, or an interior door knob, depending on whether the arrangement is to be used in a rear door or a front door. This further lever
900
has a pivot point at
902
within the housing, and is connected to a lever arm with an end pin
903
coupling with an appropriate one of the rotary coupling members.
In the arrangement of
FIG. 17
, the locking members
300
and
350
have respective projecting pins
304
and
354
which engage with a cam pin
501
on the rotary indexing and driving member
500
. In
FIG. 17
, the locking members are driven independently in opposite directions, whereas in the arrangement of
FIG. 18
they may be driven together, to reciprocate in the directions D
7
and D
8
, although they may alternatively be driven independently. The latch arrangements of
FIGS. 17 and 18
are sufficiently flexible to be adapted for use with child-safety locking and/or panic door opening, and enable selective engagement of either or both exterior door handles. They may also be integrated with electric locking, controlled by the same electric motor or by a different motor.
In the case of
FIG. 17
, for example, for use in front doors, the exterior door handle would be connected to pawl release lever
700
through cable
701
, and would be lockable by the interior door knob through lever
900
. The interior handle would drive lever
800
. For the rear doors, however, the connections with the door handles would be reversed, and lever
900
would be redundant or else could be used as a mechanical child safety lever.
The arrangement of
FIG. 17
operates as follows. Rotary coupling member
300
,
400
drives lugs
410
and
420
between a left-most position, as shown, and a right-most position at which lug
420
is free of notch
803
and lug
410
is free of notch
453
. Lug
420
permanently engages in the jaw of the fork
259
on the pawl
20
.
Rotary coupling member
350
,
450
has a lug
451
on the left-hand side which is capable of being driven clockwise by notch
702
on pawl release lever
700
. As mentioned above, it is also coupled pivotally to lever
900
through pin
903
. The rotary sliding member
450
is formed with a notch
452
capable of being driven clockwise by a lug
802
on the pawl release lever
800
. It is also formed with the notch
453
which drives lug
410
of the other rotary sliding member
400
, when at its left-most position.
Thus actuation of lever
700
drives the pawl through lugs
451
and
420
only in the position shown. If rotary sliding member
450
were to be moved to the left, then lug
451
would no longer couple with notch
702
, and lever
700
would be neutralised.
Actuation of lever
800
through notch
803
drives the lug
420
directly, but only if the rotary sliding member
400
is at its left-most position as shown. This in turn drives the pawl
20
.
Wherever the rotary coupling member
350
,
450
is at its neutral, left-most position (not shown), neutralising lever
700
, it is automatically returned to its coupling position, as shown, by the action of the other release lever
800
with its lug
802
acting on the notch
452
of rotary sliding member
450
. Thus if for example the exterior door handle is operated on a door latch in which the interior door handle has been neutralised by a child-safety lever, subsequent operation of the interior door handle serves to open the door; in other words, operation of the exterior handle overrides the child-safety function. Similarly, this arrangement provides for a panic override of door licking, enabling lever
800
to rase the interior door knob coupled to lever
900
when an interior front door handle is operated.
The arrangement of
FIG. 18
is operated analogously to that of
FIG. 17
, except that both rotary sliding member
400
.
450
co-operate with the pawl fork at the right-hand side of the arrangement. Corresponding parts are denoted with the same reference numerals.
FIG. 18A
shows schematically the detailed arrangement at the right-hand side.
These arrangements avoid the need for a mechanical child-safety lever, since the selective operation of an interior door handle can be controlled electrically from an electronic central control unit. The use of the exterior door handle as a mechanical override allows the interior handle to be opened, and this is useful for police vehicle use as well as for child safety.
The arrangements also enable double locking to be achieved, by rendering neutral the interior door knob connected to lever
900
in
FIG. 17
, for example. Thus a single electric motor is capable of controlling double locking, selective locking of interior and exterior handles, and child-safety control. Electrical child-safety locking is possible even without any separate mechanical arrangement, by virtue of the selective independent control of the interior door handle.
Existing door latches require a number of mechanical units for double locking, and often employ two motors.
Continuation of Locking or Unlocking Function After Temporary Blocking by Mechanical Door Handle Actuation
Pawl release lever
700
of
FIGS. 17 and 18
is shown in its neutral position
700
A and its fully actuated position
700
B in FIG.
19
. When actuated, at position d the lug
420
of the corresponding rotary coupling member is capable of being driven only partially form its unlocking, neutral position
420
A towards its fully locking, coupling position
420
C. This is because the lug abuts at
420
B against the edge of the lever
700
. Once the door handle is released and it returns to position e, with the notch raised to position
702
A, the lug
420
is free to move from position
420
B to its fully coupling position
420
C. In order to achieve this continued motion leftwards from B to C, even after an initial attempt which was blocked, the electric motor could be repowered, under the control of the central locking control unit
90
. However, an alternative mechanical arrangement is to provide a mechanical resilient bias which directs the lug from
420
B to
420
C. Preferably, there is an over-centre spring arrangement whose centre position of instability corresponds to the halfway position of the lug between positions
420
A and
420
C, which is slightly to the right of the intermediate position
420
B at which it engages the lever
700
. Thus the lug is biased to the right until it has moved to its midway position; beyond its midway position it is biased to the left. Such over-centre spring arrangements are well known, and typically employ a torsion spring whose ends are connected respectively to the lug and to the housing.
An alternative configuration for the rotary sliding members
400
and pawl
20
of
FIGS. 17 and 18
is shown in FIG.
20
. The fork is formed on the rotary sliding member
400
, with fork arms
430
and
431
of different length, instead of being on the pawl. The pawl is formed with a downwardly depending pin
20
A engaging in the fork. This facilitates separate sealing or isolation of the rotary coupling member and levers, which may be sealed jointly with the drive gear and motor. The pawl and latch bolt may be more easily separated from this sealed assembly, with the arrangement of
FIG. 20
, because the pin
20
A can pass through a sealable opening in the housing over the pivot
21
. This can achieve better sound proofing and can improve the life of the latch actuator by excluding grit and other abrasive materials.
A separate electric motor
70
drives a lever
194
pivoted at
195
, by way of a sliding block
191
to which it is pivoted at
192
through a slot
193
. The block
191
is constrained to move linearly and is driven by a leadscrew
198
driven by the motor through reduction gearing. The lever
194
at its pivoted end has a pin
196
connected to an actuation lever
197
capable of reciprocating linearly in directions D
3
and D
4
between positions c and d, to operate the child-safety mechanism. This couples the mechanism to the pawl selectively, as described above, for selective decoupling of the interior door handle. The electrical control avoids the need for a mechanical child-safety lever or switch in the rear door latch.
Combined Electrical Locking and Door Opening and Closing
The arrangements shown in
FIGS. 21
to
26
enable a single electric motor to control independent functions for the latch arrangement, such as electric door locking an unlocking (central locking) and door opening and/or closing. Several independent innovations are disclosed, as with the other arrangements.
The latch arrangement in
FIG. 21
has a rotary indexing and driving member
50
with a single cam pin
30
having two neutral positions Np
1
and Np
2
, and spring biased into those positions by spring
1009
which also absorbs shock. Controlled operation in directions D
1
and D
2
causes independent actuation of a lever arm
1001
, for door locking, and cam finger
1004
of a shuttle mechanism
1006
. Electric locking is achieved by rotating the lever
1001
, against its return torsion spring
1002
, in directions D
11
or D
12
, appropriately to actuate the pair of locking members
300
and
350
together. As shown, the cam
1003
of lever
1001
rotates from a neutral position C to either extreme positions C
1
, C
2
, depending on the rotary direction of the cam pin
30
.
Door opening is achieved by the shuttle
1006
which has an abutment surface
1005
acting on the lever
1008
or pawl
20
. Door closing is achieved by the abutment surface
1010
at the lower end of the shuttle which abuts against the latch bolt extension
37
to move it from position B to position B
1
. As shown, the cam finger
1004
moves between a neutral position Np and extreme positions P
1
and P
2
. As before, the shuttle is controlled by a tension compression coil spring
1007
.
The arrangement of
FIG. 22
shows haw a single cam finger
1012
on the rotary indexing and driving member
50
selectively controls three functions: the single lever
1001
of
FIG. 21
is replaced by two such levers
1010
,
1011
, equi-angularly disposed around the rotary member
50
. The cam finger
1012
has three neutral positions Np
1
, Np
2
and Np
3
, to which it is spring biased by means not shown. This enables the independent control of the two locking members
300
and
350
as shown.
A further variant is shown in
FIG. 23
in which a fourth actuation member is selectively driven by the cam finger
1012
, and the four actuation members
1020
to
1023
are equi-angularly disposed around the rotary member
50
. This enables a single electric motor to control the selective locking of two handles and electric door opening and closing, as in
FIG. 22
, and an auxiliary function, such as a child-safety operation. In a variant of the arrangement of
FIG. 23
, not shown, different cams
1012
could be disposed in different planes spaced axially of the rotary member
50
, as on a cam shaft, to increase the flexibility of the multiple actuations.
A further variation is shown in
FIG. 24
, especially suitable for use with a tailgate of boot latch. The single cam pin
30
selectively drives pawl
20
through a rotary lever
1030
mounted co-axially with the pawl, and arranged with a dependent flang
1031
to drive the pawl in direction D
3
, but to rotate in direction D
7
freely without actuating the pawl. Thus the cam pin
30
is able to rotate clockwise in direction D
6
to rotate the lever
1030
without being hindered by the pawl. The cam pin
30
also actuates a lever arm
1034
for operating the locking member
300
which is also coupled to the key mechanism through link
1033
. The lick mechanism selectively couples the handle or knob through linkage
245
to the pawl
20
.
As with other arrangements, the rotary member
50
may be spring biased into its neutral positions for example by a sinuous rotary cam surface against which the leaf spring
1037
is forced radially.
FIG. 25
illustrates how the cam pin
30
can be arranged to drive two sliding locking members
300
and
350
through appropriate pins or projections
304
and
354
respectively. Projection
354
is moveable by the cam pin
30
between positions A, A
1
, A
2
and A
3
; projection
304
is correspondingly moveable between positions B, B
1
, B
2
and B
3
. The stable positions of the projections
304
,
354
are those positions on the broken line, shown as A
1
, A
2
and B
1
, B
2
, and they are displaced between those positions by the cam pin
30
and they return to those positions after the passage of the cam pin
30
. In order to allow the passage of the cam pin
30
, they are resiliently moveable outwardly to the corresponding extreme positions A, A
3
, B and B
3
. By way of example, the resilience is achieved, as shown in
FIG. 26
, by arranging for the projection on the locking members
300
,
350
to take the form of a toggle
1050
pivoted at
1052
and biased into its central position by torsion spring
1053
disposed on the pivot and held by fixed block
1054
. The toggle or finger
1050
can be displaced rotationally to position P
1
, to be returned to its neutral position P, by spring arm
1051
. Similarly, it can be displaced to position P
2
to be returned to its neutral position by spring arm
1055
.
Alternative resilient formations are of course possible.
Housing for Latch Actuator
As described above, the latch actuator can be formed in a compact box-shaped housing. As shown in
FIG. 27
, the housing can be formed from two opposed end plates
3017
and
3018
together with a side wall
3027
. This arrangement can be secured to the door frame
3023
by appropriate bolts
3024
,
3025
and
3026
screwing respectively into an axis
3019
, the pivot axis
21
for the pawl
20
and other mechanisms
3020
,
3021
and
3022
, and the pivot axis
15
for the latch bolt
11
. These pivot axes
21
and
15
have axial upward projections extending through the face plate
3017
, and include radial enlargements
3015
and
3028
respectively.
An elongate closure plate
3010
has keyhole-shaped apertures
3012
and
3013
, coupling with the projecting pivot axes
3015
and
3028
. During manufacture, once the latch arrangement components have been assembled as shown, and the face plate
3017
inserted over the three spindles, the closure plate
3010
is located with the larger circular portion of each keyhole
3012
,
3013
passing over the enlargements
3015
,
3028
. At this point, a corresponding aperture
3011
in the closure plate is slightly misaligned with the axis of the spindle
3019
as shown. The closure plate
3010
is then slid, in direction A, over the face plate
3017
, to lock it into position. The inner portions of each keyhole slide over and retain the respective spindles on the pivot axes
21
and
15
. The closure plate then bears against the enlargements or studs
3015
and
3028
. At this point, aperture
3011
in the closure plate reaches the axis of the spindle
3019
, and a closure cap
3014
is inserted with a push fit through aperture
3011
and a corresponding aperture in the face plate
3017
, to secure the closure plate against sliding movement.
This arrangement allows non-destructive disassembly of the latch arrangement, simply by removing the cap
3014
sliding the closure plate
3010
and then removing the closure plate and disassembling the remainder of the latch assembly. Thus faulty components can be replaced at any time.
Each end of the latch housing may have its own such closure plate.
Claims
- 1. A latch arrangement for an automotive door or other closure, comprising an electric motor coupled to a rotary driving and indexing member having at least one projection, the projection being resiliently displaceable, at least one actuation member arranged to be driven by a respective projection from the driving and indexing member, and means for controlling the electric motor selectively to position the driving and indexing member and thereby to drive the, at least one actuation member to perform a required action in the latch assembly for locking or unlocking the latch and/or completing closure of the door or other closure member.
- 2. A latch arrangement according to claim 1, wherein the or each projection and/or the or each actuation member is resiliently displaceable at the point of mutual contact to allow a limited displacement after completion of the required actuation.
- 3. A latch arrangement according to claim 1, in which the projection is resiliently displaceable.
- 4. A latch arrangement according to claim 1, in which the or each actuation member is spring-biased towards its point of contact with the said projection from the driving and indexing member.
- 5. A latch arrangement according to claim 1, in which the driving and indexing member is resiliently biased towards neutral stable rotary positions thereof, so that it is driven preferentially to such positions from intermediate, unstable positions.
- 6. A latch arrangement according to claim 1, wherein such arrangement is suitable for an automobile door or other closure, for releasably detaining a striker, the latch arrangement further comprising: a latch bolt shaped to retain the striker at a latching position and to release the striker at an unlatching position of the latch bolt; a locking member mounted for movement between a locking position, at which it retains the latch bolt and its latching position, and an unlocking position, at which it allows the latch bolt to move to its unlatching position; and means for locking the locking member.
- 7. A latch arrangement according to claim 6, in which the driving and indexing member is arranged to drive the means for locking the locking member and also the latch bolt, in order to complete the closure of the door or other closure.
- 8. A latch arrangement according to claim 6, in which the driving and indexing member is arranged selectively to release the locking member to allow the door to open.
- 9. A latch arrangement according to claim 6, comprising at least two locking member release levers connectable drivingly to respective external controls such as interior and exterior door handles and coupled to the locking member for unlocking it; and two corresponding coupling members each selectively moveable between a coupling position, at which it couples the locking member release lever to the locking member, and a neutral position at which it does not; and in which the said driving and indexing member provides selective electrical control of the positions of the coupling members in order to selectively couple one or both of the exterior controls for the opening of the door or other closure.
- 10. A latch arrangement according to claim 9, wherein the functions of selective central locking and power-assisted door closing are effected using only the said one motor.
- 11. A latch arrangement according to claim 9, wherein the functions of selective central locking and power-assisted door closing and opening are effected using only the said one motor.
- 12. A latch arrangement according to claim 6, further comprises a locking and unlocking means for locking and unlocking the locking member and in which, over different phases of its rotary movement the driving and indexing member selectively drives the locking and unlocking means and the latch bolt.
- 13. A latch arrangement according to claim 6, in which the locking member is a pawl.
- 14. A rotary indexing mechanism for driving actuators in a latch arrangement according to claim 1.
- 15. A latch arrangement for an automotive door or other closure, comprising an electric motor coupled to a rotary driving and indexing member having at least one projection, at least one actuation member arranged to be driven by a respective projection from the driving and indexing member, and means for controlling the electric motor selectively to position the driving and indexing member and thereby to drive the at least one actuation member to perform a required action in the latch assembly for locking or unlocking the latch and/or completing closure of the door or other closure member, the driving and indexing member being resiliently biased towards neutral stable rotary positions thereof, so that it is driven preferentially to such positions from intermediate, unstable positions.
- 16. A latch arrangement according to claim 15, wherein each projection and/or each actuation member is resiliently displaceable at the point of mutual contact to allow a limited displacement after completation of the required actuation.
- 17. A latch arrangement according to claim 15, in which the projection is resiliently displaceable.
- 18. A latch arrangement according to claim 15, in which the or each actuation member is spring-biased towards its point of contact with the said projection from the driving and indexing member.
- 19. A latch arrangement according to claim 15, wherein such arrangement is suitable for an automobile door or other closure, for releasably detaining a striker, the latch arrangement further comprising: a latch bolt shaped to retain the striker at a latching position and to release the striker at an unlatching position of the latch bolt; a locking member mounted for movement between a locking position, at which the locking member retains the latch bolt and its latching position, and an unlocking position, at which the locking member allows the latch bolt to move to its unlatching position; and means for locking the locking member.
- 20. A latch arrangement according to claim 19, wherein the driving and indexing member is coupled for selectively and independently driving the locking member, for electric door opening, and also the locking means, for electric locking and unlocking.
- 21. A latch arrangement according to claim 19, in which the driving and indexing member is arranged to drive the locking means and also the latch bolt, in order to complete the closure of the door or other closure.
- 22. A latch arrangement according to claim 19, in which the driving and indexing member is arranged selectively to release the locking member to allow the door to open.
- 23. A latch arrangement according to claim 19, comprising at least two locking member release levers connectable drivingly to respective external controls and coupled to the locking member for unlocking the locking member; and two corresponding coupling members each selectively moveable between a coupling position, at which the coupling member couples the locking member release lever to the locking member, and a neutral position at which the coupling member does not; and in which the said driving and indexing member provides selective electrical control of the positions of the coupling members in order to selectively couple one or both of the exterior controls for the opening of the door or other closure.
- 24. A latch arrangement according to claim 23, wherein the functions of selective central locking and power-assisted door closing are effected using only the said one motor.
- 25. A latch arrangement according to claim 23, wherein the functions of selective central locking and power-assisted door closing and opening are effected using only the said one motor.
- 26. A latch arrangement according to claim 19 further comprises a locking and unlocking means for locking and unlocking the locking member and, in which, over different phases of its rotary movement, the driving and indexing member selectively drives the locking and unlocking means and the latch bolt.
- 27. A latch arrangement according to claim 19, in which the locking member is a pawl.
- 28. A rotary indexing mechanism for driving actuators in a latch arrangement according to claim 15.
- 29. A latch arrangement for an automotive door or other closure, comprising an electric motor coupled to a rotary driving and indexing member having at least one projection, at least one actuation member arranged to be driven by a respective projection from the driving and indexing member, a means for controlling the electric motor selectively to position the driving and indexing member and thereby to drive the at least one actuation member to perform a required action in the latch assembly for locking or unlocking the latch and a locking member mounted for movement between a locking position and an unlocking position, the indexing member being coupled for selectively and independently driving the locking member, for electric door opening, wherein the projection is resiliently displaceable.
- 30. A latch arrangement for an automotive door or other closure, comprising an electric motor coupled to a rotary driving and indexing member having at least one projection, at least one actuation member arranged to be driven by a respective projection from the driving and indexing member, a means for controlling the electric motor selectively to position the driving and indexing member and thereby to drive the at least one actuation member to perform a required action in the latch assembly for locking or unlocking the latch and a locking member mounted for movement between a locking position and an unlocking position, the indexing member being coupled for selectively and independently driving the locking member, for electric door opening, wherein the driving and indexing member is resiliently biased towards neutral stable rotary positions thereof, so that the driving and indexing member is driven preferentially to such positions from intermediate, unstable positions.
- 31. A latch arrangement for an automotive door or other closure, comprising an electric motor coupled to a rotary driving and indexing member having at least one projection, at least one actuation member arranged to be driven by a respective projection from the driving and indexing member, a means for controlling the electric motor selectively to position the driving and indexing member and thereby to drive the at least one actuation member to perform a required action in the latch assembly for locking or unlocking the latch and a locking member mounted for movement between a locking position and an unlocking position, the indexing member being coupled for selectively and independently driving the locking member, for electric door opening, at least two locking member release levers connectable drivingly to respective external controls and coupled to the locking member for unlocking the locking member; and two corresponding coupling members each selectively moveable between a coupling position, at which the coupling members couple the locking member release lever to the locking member, and a neutral position at which the coupling members do not; and in which the said driving and indexing member provides selective electrical control of the positions of the coupling members in order to selectively couple one or both of the exterior controls for the opening of the door or other closure.
- 32. A latch arrangement according to claim 31, wherein the functions of selective central locking and power-assisted door closing are effected using only the said one motor.
- 33. A latch arrangement according to claim 31, wherein the functions of selective central locking and power-assisted door closing and opening are effected using only the said one motor.
- 34. A latch arrangement for an automotive door or other closure, comprising an electric motor coupled to a rotary driving and indexing member having at least one projection, at least one actuation member arranged to be driven by a respective projection from the driving and indexing member, a means for controlling the electric motor selectively to position the driving and indexing member and thereby to drive the at least one actuation member to perform a required action in the latch assembly for locking or unlocking the latch and/or completing closure of the door or other closure member, and a locking member mounted for movement between a locking position and an unlocking position, the indexing member being coupled for selectively and independently driving the locking member, for electric door opening, and at least two locking member release levers connectable drivingly to respective external controls and coupled to the locking member for unlocking the locking member; and two corresponding coupling members each selectively moveable between a coupling position, at which the coupling members couple the locking member release lever to the locking member, and a neutral position at which the coupling members do not; and in which the said driving and indexing member provides selective electrical control of the positions of the coupling members in order to selectively couple one or both of the exterior controls for the opening of the door or other closure.
- 35. A latch arrangement according to claim 34, wherein each projection and/or each actuation member is resiliently displaceable at the point of mutual contact to allow a limited displacement after completion of the required actuation.
- 36. A latch arrangement according to claim 34, in which the projection is resiliently displaceable.
- 37. A latch arrangement according to claim 34, in which each actuation member is spring-biased towards its point of contact with the said projection from the driving and indexing member.
- 38. A latch arrangement according to claim 34, in which the driving and indexing member is resiliently biased towards neutral stable rotary positions thereof, so that it is driven preferentially to such positions from intermediate, unstable positions.
- 39. A latch arrangement according to claim 34, wherein such arrangement is suitable for an automobile door or other closure, for releasably detaining a striker, the latch assembly further comprising: a latch bolt shaped to retain the striker at a latching position and to release the striker at an unlatching position of the latch bolt and means for locking and unlocking the locking member, the locking member being mounted for movement between a locking position, at which the locking member retains the latch bolt and its latching position, and an unlocking position, at which the locking member allows the latch bolt to move to an unlatching position.
- 40. A latch arrangement according to claim 39, wherein the driving and indexing member is coupled for selectively and independently driving the locking member, for electric door opening, and also the locking means, for electric locking and unlocking.
- 41. A latch arrangement according to claim 34, in which the driving and indexing member is arranged to drive the locking means and also the latch bolt, in order to compete the closure of the door or other closure.
- 42. A latch arrangement according to claim 34, in which the driving and indexing member is arranged selectively to release the locking member to allow the door to open.
- 43. A latch arrangement according to claim 34, wherein the functions of selective central locking and power-assisted door closing are effected using only the said one motor.
- 44. A latch arrangement according to claim 34, wherein the functions of selective central locking and power-assisted door closing and opening are effected using only the said one motor.
- 45. A latch arrangement according to claim 34, further comprises a locking and unlocking means for locking and unlocking the locking member and, in which, over different phases of its rotary movement, the driving and indexing member selectively drives the locking and unlocking means and the latch bolt.
- 46. A latch arrangement according to claim 34, in which the locking member is a pawl.
- 47. A rotary indexing mechanism for driving actuators in a latch arrangement according to claim 34.
US Referenced Citations (11)
Foreign Referenced Citations (4)
Number |
Date |
Country |
528082 |
Oct 1940 |
EP |
0106725 |
Apr 1984 |
EP |
745746 |
Dec 1996 |
EP |
WO 9628666 |
Sep 1996 |
WO |