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(11) | EP 1 138 855 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Vehicle door latch undogging mechanism |
| (57) The door latch (10) has a rotatable fork bolt (30) that engages a striker pin (91).
A detent (32) is pivotable into engagement with the fork bolt to latch the door latch.
An intermittent lever (34) is pivotally attached to the detent. An unlatching lever
(44) has an ear (46) that is pivotable into contact with a tab (48) on the intermittent
lever to release the fork bolt. A pivotable locking lever (40) has a slot (41) that
pivotally receives a pivot pin (38) on the intermittent lever. A cam surface (152)
on the fork bolt engages the detent and moves the intermittent lever away from the
fork bolt when the fork bolt is rotated toward a latched position by the striker pin.
A cam follower (160) on the intermittent lever follows a cam surface (162) on the
unlatching lever and moves the locking lever to an unlocked position. Holding an outside
door handle in an open position when the door is closed moves the cam surface on the
unlatching lever out of contact with the cam follower and leaves the locking lever
locked. |
TECHNICAL FIELD
[0001] This invention relates generally to a vehicle door latch and more particularly to a vehicle door latch that has a lock that prevents the vehicle door from being unlatched by an outside door handle when engaged and that disengages the lock when the door is closed.
BACKGROUND OF THE INVENTION
[0002] An automotive closure, such as a door for an automobile passenger compartment, is hinged to swing between open and closed positions and conventionally includes a door latch that is housed between inner and outer panels of the door. The door latch functions in a well known manner to latch the door when it is closed and to lock the door in the closed position or to unlock and unlatch the door so that the door can be opened manually. The door latch is operated remotely from inside the passenger compartment by two distinct operators - a sill button or electric switch that controls the locking function and a handle that controls the latching function. The door latch is also operated remotely from the exterior of the automobile by a handle or push button that controls the latching function. A second distinct exterior operator, such as a key lock cylinder, may also be provided to control the locking function, particularly in the case of a front vehicle door. Each operator is accessible outside the door structure and extends into the door structure where it is operatively connected to the door latch mechanism by a cable actuator assembly or linkage system located inside the door structure.
[0003] U.S. Patent 5,277,461 granted to Thomas A. Dzurko et al, January 11, 1997 for a vehicle door latch, which is hereby incorporated in this patent specification by reference, discloses a typical door latch. The door latch disclosed in the Dzurko '461 patent includes and inside latch operating lever that is pivotally mounted on a flange of a metal faceplate and that is connected by a suitable linkage for rotation by an inside door handle (not shown). See column 4, lines 10-18 of the Dzurko '461 patent. The door latch also includes an inside lock operating lever that is pivotally mounted on the flange of the metal faceplate near the inside latch operating lever. The inside lock operating lever is operated by an inside sill button or lock slide. See column 5, lines 46-58 and column 6, lines 8-15 of the Dzurko '461 patent. The door latch disclosed in the Dzurko '461 patent is released from the passenger compartment in two stages. First the inside lock operating lever is rotated counter-clockwise by an inside sill button or lock slide to unlock the door latch. Then the inside latch operating lever 56 is rotated clockwise by an inside door handle to unlatch the door latch so that the vehicle door may be opened manually.
[0004] Door latches of the type disclosed in the Dzurko '461 patent have been used successfully by General Motors Corporation for many years. While these door locks are useful for many purposes, there are instances where it is desirable to prevent inadvertent locking of the vehicle door with the vehicle keys left in the ignition or elsewhere in the vehicle.
SUMMARY OF THE INVENTION
[0005] The vehicle door latch has a housing. A forked bolt is journalled in the housing and is pivotal between a bolt closed position and a bolt open position. A detent is journalled on the housing and is pivotable into engagement with the forked bolt to latch the forked bolt in the bolt closed position. An unlatching lever is pivotally attached to the housing for pivotal movement between a latched position and an unlatched position. A locking lever with a slot is pivotally attached to the housing for pivotal movement between a locking lever locked position and a locking lever unlocked position. An intermittent lever, with a tab and an intermittent lever cam surface, is pivotally attached to the detent. A pivot pin on the intermittent lever is received in the slot in the locking lever. The tab is in the path of movement of the unlatching lever when the locking lever is in the locking lever unlocked position. The tab is out of the path of movement of the unlatching lever when the locking lever is in the locking lever locked position. Upon continued rotation of the forked bolt, the cam surface pivots the detent, moves an intermittent lever cam surface into contact with an unlatching lever cam surface and pivots the locking lever to the locking lever unlocked position.
[0006] The modified fork bolt, intermittent lever and unlatching lever cooperate with the detent to move the locking lever to the locking lever unlocked position upon closing of a vehicle door thereby preventing a latch from being unintentionally locked when the door is closed. The vehicle door can be locked with a key or other outside locking device after the vehicle door is closed.
[0007] The vehicle door can be intentionally locked without a key by moving the locking lever to the locking lever locked position when the door is open, holding the unlatching lever in an unlatched position and closing the door. Holding the unlatching lever in an unlatched position holds the unlatching lever cam surface out of contact with the intermittent lever cam surface during closing of the door. Holding the unlatching lever cam surface out of contact with the intermittent lever cam surface during closing of the door prevents the locking lever from being moved to the locking lever unlocked position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The presently preferred embodiment of the invention is disclosed in the following description and in the accompanying drawings, wherein:
Figure 1 is an exploded perspective front view of a vehicle door latch with an undogging mechanism;
Figure 2A is a perspective rear view of the fork bolt that is shown in figure 1;
Figure 2B is a perspective rear view of the intermittent lever that is shown in figure 1;
Figure 2C is a perspective rear view of the unlatching lever that is shown in figure 1;
Figure 3 is an elevational rear view of the undogging mechanism shown in figure 1 in an unlatched and locked position;
Figure 4 is a view similar to figure 3 with the fork bolt in a mid position; and
Figure 5 is a view similar to figure 3 with the undogging mechanism in a latched and unlocked position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0009] Referring now to figure 1, the vehicle door latch 10 has a multi-piece enclosure that comprises a plastic housing 12, a metal faceplate 14 and a metal back plate 16. The plastic housing 12 and the metal back plate 16 are held together by three flanged, internally threaded bushings 18, 20 and 22 that are inserted into three holes in the plastic housing 12, then through three aligned holes in the back plate 16 and then flanged over the back plate. The metal faceplate 14 has three bolt holes 24 that are aligned with the bushings 18, 20 and 22 when the metal faceplate is attached to the plastic housing 12 by a screw 26. The metal faceplate 14 and the metal back plate 16 have lower portions below the plastic housing 12 that are held together by a flanged stud 28 that has projecting pins at each end that are inserted in holes in the plates and peened or headed over.
[0010] The latch mechanism of the vehicle door latch 10 comprises a fork bolt 30 and a cooperating detent 32 that are pivotally mounted on bushings 20 and 18 respectively and located in a chamber of the plastic housing 12 behind the metal faceplate 14. The fork bolt 30 is biased clockwise, toward an unlatched position, by a coil spring 29. Coil spring 29 is disposed in a curved slot in the plastic housing 12 behind the fork bolt 30 and it engages a depending spring abutment block 31 of the fork bolt 30 at one end. Detent 32 is biased counterclockwise into engagement with the fork bolt 30 by a coil spring 33 that surrounds the bushing 18 and that has one end engaging an ear 35 of the detent 32. Detent 32 engages shoulder 60 and holds the fork bolt lever 30 in a primary latched position against the bias of spring 29 as shown in figure 1. Detent 32 also can engage fork bolt 30 at shoulder 62 and hold it in an intermediate secondary latched position. Detent 32 engages the fork bolt 30 on its foot 64 in its unlatched position.
[0011] The latch mechanism further comprises an intermittent lever 34 for operating detent 32. Intermittent lever 34 is located in the chamber of the plastic housing 12 behind detent 32. It has two integral pivot pins 36 and 38. Pivot pin 36 is journalled in a hole 32a in detent 32 so that the detent 32 rotates clockwise from the latched position shown in figure 1 (and out of latched engagement with the fork bolt 30) to an unlatched position when the intermittent lever 34 is pulled down. The pivot pin 38 is disposed in a slot 41 of a locking lever 40 that pivots the intermittent lever 34 counterclockwise about pivot pin 36 from the unlock position shown in figure 1 to a lock position in figure 3. The locking lever 40 is journalled on the stud 28 between flange 42 and faceplate 14. Briefly the locking lever 40 is rotated clockwise to lock the door latch 10 or counterclockwise to unlock the door latch. Clockwise rotation of the locking lever 40 from the unlocked position shown in figure 1, pivots intermittent lever 34 counterclockwise about pivot pin 36 to a position where it is uncoupled from and out of the path of travel of transfer or unlatching lever 44 described below. A more complete description of the locking lever 40 and locking mechanism is given after the latch mechanism is described.
[0012] The latch mechanism further comprises a transfer or unlatching lever 44 that is journalled on a reduced diameter portion of the stud 28 spaced rearwardly of the flange 42. The transfer lever 44 has an ear 46 at one end that is engageable with an integral, rearwardly projecting tab 48 of the intermittent lever 34 so that the intermittent lever 34 is pulled down when the transfer level 44 is rotated clockwise as viewed in figure 1.
[0013] The latch mechanism further comprises an outside latch operating lever 50 and a coil return spring 52. The outside latch operating lever 50 is also journalled on the reduce diameter portion of the stud 28 behind transfer level 44. It has a bent tab 54 that engages ear 46 of the unlatching lever 44 when it is rotated clockwise on the stud 28. Outside latch operating lever 50 has an aperture 51 that is connected by suitable linkage for rotation by an outside door handle (not shown).
[0014] The coil return spring 52 is disposed around the stud 28 and located between the flange 42 and the unlatching lever 44. One end of the coil spring 52 engages the bottom of transfer lever 44 and the other end engages the bottom of the plastic housing 12 above transfer lever 44 so that transfer lever 44 and outside operating lever 50 are biased counterclockwise to a rest position where tab 54 engages a stop at the bottom of plastic housing 12.
[0015] The latch mechanism further comprises an inside latch-operating lever 56 that is pivotally mounted on a flange 15 of the metal faceplate 14. The inside latch operating lever 56 has a tab 57 that engages a second ear 61 of transfer lever 44 so that the inside latch operating lever 56 also rotates the transfer lever 44 clockwise when it is rotated counterclockwise. The inside latch operating lever 56 is connected to a suitable cable actuator assembly or linkage system (not shown) for rotation by an inside door handle or other operator (not shown).
[0016] Fork bolt 30 has a conventional slot or throat 58 for receiving and retaining striker pin 91 of a striker assembly 93 that is attached to the vehicle door pillar to latch the vehicle door in the closed position (not shown). Fork bolt 30 also includes a primary latch shoulder 60, an intermediate secondary latch shoulder 62 and a radially projecting foot 64. Fork bolt 30 preferably has a plastic coating that covers a surface of the slot 58 that is engaged by a striker pin 91 for energy absorption and quiet operation when the vehicle door is slammed shut.
[0017] Detent 32 has a sector shaped catch 68 that engages the radially projecting foot 64 when the fork bolt 30 is in the unlatched position (not shown). The sector shaped catch 68 positively engages the primary and latch shoulders 60 and 62 to hold the fork bolt 30 in either the primary or the intermediate secondary latched positions shown in figure 1 and not shown, respectively. Detent 32 also preferably includes a plastic coating that has an integral bumper. The bumper engages the bushing 22 to stop counterclockwise pivoting of the detent lever 32 under the bias of spring 33. This bumper also absorbs energy and quiets operation when the door is slammed shut.
[0018] The latch mechanism described above operates as follows. When the door latch 10 is in an unlatched and unlocked condition, for bolt 30 is poised to receive striker pin 91 that projects into aligned fish mouth slots 74 and 75 of plastic housing 12 and metal faceplate 14 when the door is shut. The entering striker pin 91 engages the back of the throat 58 and rotates fork bolt 30 counterclockwise against the bias of spring 29 until fork bolt 30 is rotated to the primary latch position shown in figure 1 where fork bolt 30 captures the striker pin 91 in the throat 58. Fork bolt 30 is held in the primary latch position by catch 68 of detent 32 engaging the primary latch shoulder 60 of fork bolt 30.
[0019] Catch 68 rides along the periphery of the fork bolt 30 under the bias of spring 33 as fork bolt 30 rotates counterclockwise from the unlatched position to the primary latch position shown in figure 1. During this travel, catch 68 rides under the foot 64 into engagement with the intermediate secondary latch shoulder 62 and then into engagement with primary latch shoulder 60. Engagement of catch 68 with the intermediate secondary latching shoulder 62 is sufficient to hold the vehicle door closed in the event that the vehicle door is not shut with sufficient force so that catch 68 engages primary latch shoulder 60.
[0020] The vehicle door latch 10 is not locked and the inside latch operating assembly 56 is not disabled by the security lock so that the vehicle door can be opened simply by operating either an inside or outside door handle or the like to rotate the unlatching lever 44 clockwise and the ear 46 down as viewed in figure 1. Ear 46 engages projection 48 of intermittent lever 34 and pulls the intermittent lever 34 down from the primary latch position shown in figure 1. As the intermittent lever 34 moves down, it rotates detent 32 clockwise against the bias of spring 33 from the primary latch position shown in figure 1. Fork bolt 30 is then free to rotate counterclockwise under the bias of spring 29 from the primary latch position shown in figure 1 to an unlatched position as the striker pin 91 is pulled out of the aligned fish mouth slots 74 and 75 when the vehicle door is opened.
[0021] The lock mechanism is actuated by rotating the locking lever 40 that is journalled on stud 28 between flange 42 and faceplate 14 clockwise. Clockwise rotation of the locking lever 40 rotates intermittent lever 34 counterclockwise about the pivot pin 36 that is journalled in the detent 32 due to the engagement of the second pivot pin 38 of the intermittent lever 34 in slot 41 of locking lever 40. Intermittent lever 34 is thus rotated counterclockwise from the unlocked position shown in figure 1 to an unlocked position where tab 48 is repositioned out from under ear 46 of unlatching lever 44. Consequently when the door handles or the like are operated so as to rotate the transfer level 44 clockwise to the unlatching position, ear 46 simply bypasses tab 48 without transferring any motion to intermittent lever 34. Intermittent lever 34 is not therefore pulled down to rotate detent 32 to the unlatch position. In other words the transfer lever 44 simply free wheels so that operation of the door handles or their equivalent is not effective.
[0022] The lock mechanism further comprises an inside lock operating lever 80 and an optional outside lock-operating lever 82. Inside lock operating lever 80 is pivotally mounted on flange 15 of the metal faceplate 14 at a location spaced from the pivot for the inside latch operating lever 56. Inside lock operating lever 80 has an ear 84 that fits in a slot 85 at one end of locking lever 40. Locking lever 40 has a protuberance 88 that projects through a sector shaped hole 86 in outside lock operating lever 82 and then through a smaller sector shaped hole 90 in faceplate 14.
[0023] Protuberance 88 and sector shaped hole 90 limit rotation of locking lever 40 from an unlocked position shown in figure 1 where protuberance 88 engages the upper edge of hole 90 to a locked position (not shown) where protuberance 88 engages the lower edge of hole 90.
[0024] Locking lever 40 is rotated clockwise from the unlocked position shown in figure 1 to the locked position by rotating inside lock operating lever 80 counterclockwise as viewed in figure 1. Inside lock operating lever 80 is actuated by a suitable actuator assembly or linkage system (not shown) by an inside sill button or other operator (not shown).
[0025] Locking lever 40 can also be rotated clockwise from the unlocked position shown in figure 1 to the locked position by rotating outside lock operating lever 82 clockwise. Outside lock operating lever 82 is optional and normally used only in front vehicle doors where the lock operating lever 82 is generally actuated by a key lock cylinder through a suitable linkage (not shown). Locking lever 40 also has a slot 87 for operating the locking lever 40 by a linear electric or vacuum motor.
[0026] An undogging mechanism 100 unlocks the lock mechanism when the door is closed and the locking lever 40 is in a locking position. The purpose of the undogging mechanism 100 is to prevent the inadvertent locking of a vehicle with the keys inside the passenger compartment. However, a person can override the undogging mechanism 100 and lock the doors without a key if desired as explained below.
[0027] The undogging mechanism 100 includes fork bolt 30, intermittent lever 34 and transfer or unlatching lever 44 that are as shown in detail figures 2A, 2B and 2C respectively. Fork bolt 30 has a foot 50 with a radially outer cam surface 152 having a radius about the axis of the bushing 20 that increases from the heel 154 to the toe 156. Intermittent lever 34 has a cam follower 160 on the side opposite the pivot pin 38. Unlatching lever 34 has a straight inclined cam surface 162.
[0028] The door latch 10 as shown in figure 3 has back plate 16, housing 14 and spring 29 removed for clarity. The fork bolt 30 is in the unlatched position where a stop surface 164 on fork bolt 30 is in contact with the housing 12 (not shown). The locking lever 40 is in a locked position. In the locked position, the pivot pin 38 on intermittent lever 34 which projects into the slot 41 on the locking lever 40, locates intermittent lever 34 in a lock position where tab 48 on intermittent lever 34 is out of the path of movement of ear 46 on unlatching lever 44. The pivot pin 36 is journalled in a hole 32a in the detent 32. When tab 48 on the unlatching lever 44 is out of the path of movement of ear 46 the door latch 10 is locked and cannot be unlatched.
[0029] The unlatched and locked position of the parts described above occurs when the door is open and the lock mechanism has been actuated for instance by a pushing conventional sill button down.
[0030] The undogging mechanism 100 automatically unlocks door latch 10 when the door is closed to avoid an inadvertent lock-out. Closing the door moves the fork bolt 30 into contact with the striker pin 91. The striker pin 91 rotates the fork bolt 30 clockwise as shown in figure 3 from the unlatched position shown in figure 3 to the secondary latched position shown in figure 5 through the mid position shown in figure 4. Rotation of fork bolt 30 also rotates detent 32 counterclockwise about bushing 18. The detent 32 is rotated counterclockwise by cam surface 152 on fork bolt 30. Rotation of the detent 32 counterclockwise moves the pivot pin 36 and intermittent lever 34 downward and moves the pivot pin 38 (shown in figure 1) on intermittent lever 34 downward in slot 41 of locking lever 40. Downward movement of pin 38 brings cam follower 160 into contact with cam surface 162 on unlatching lever 44. Continued movement of the cam follower 160 along the cam surface 162 pivots the intermittent lever 34 about pivot pin 36 counterclockwise as shown in figure 3. This pivotal movement of intermittent lever 34 and the pivot pin 38 pivots locking lever 40 from the locked position shown in figure 3 to an unlocked position shown in figures 4 and 5 so that the latched door is unlocked.
[0031] The locking lever 40 is pivotally mounted on the flanged stud 28 as shown in figure 1. A coil spring 170 is mounted on a stud 172 that is integral with the housing 12. The coil spring 170 has one end that is anchored on the housing and an end 174 that is received in a slot 176 or a slot 178 in the locking lever 40. When the end 174 of the spring 170 is in the slot 176, the tab 48 is out of the path of movement of the unlatching lever 44 and the door 10 is locked. When the end 174 of the spring 170 is in the slot 178 the tab 48 is in the path of movement of the unlatching lever 144 and the latch 10 is unlocked. The slots 176 and 178 are separated from each other by a tip 180. Rotating the locking lever 140 a few degrees about the flanged stud 28 in one direction or the other cams the end 174 of spring 170 up one side of the tip 180 and into the other slot 176 or 178.
[0032] The door latch 10 as shown in figure 5 is in a secondary latched and unlocked position. In the fully latched position, the shoulder 60 is engaged by a locking surface 182 of the catch 68 on the detent 32. In secondary latched position the shoulder 62 at the toe 156 of foot 150 is in engagement with the locking surface 182 on the detent 32 thereby holding the forked bolt 130 in a secondary latched position. Since the unlocking lever 40 is in an unlocked position, the tab 48 on intermittent lever 34 is in the path of movement of ear 46 on unlatching lever 44. Movement of the unlatching lever 44 by an inside door handle or by an outside door handle moves ear 46 into engagement with tab 48, moves pivot pin 38 in slot 41 away from bushing 20, moves intermittent lever 34 away from fork bolt 30 and pivots the locking surface 182 on detent 32 out of the path of shoulder 62 of fork bolt 30 thereby unlatching the fork bolt.
[0033] Locking lever 40 can be rotated to a locked position by various levers and activators. However, closing the door after the locking lever 40 has been rotated to a locked position automatically results in clockwise rotation of fork bolt 30 and rotation of locking lever 40 to the unlocked position by the undogging mechanism as explained above. However, the undogging mechanism can be overridden. For instance, if the operator of a vehicle wishes to lock an open door without a key, locking lever 40 is rotated to a locked position by the sill button or the like while fork bolt 30 remains in the unlatched position as shown in figure 3. The outside door handle is then moved to an open position rotating unlatching lever 44 counterclockwise about the flanged stud 28 as shown in figure 3. This moves the ear 46 to a position to one side of the tab 48 and moves the cam surface 162 away from the cam follower 160. The door can then be closed without automatically unlocking the lock mechanism because cam follower 160 does not contact cam surface 162. Pivot pin 38 of intermittent lever 34 merely slides down slot 41 and does not rotate locking lever 40 to an unlocked position. When the door is closed, the door handle can then be released leaving the door latched and locked.
1. A vehicle door latch (10) comprising:
a housing (12, 14, 16);
a fork bolt (30) journalled in the housing (12,14,16) and pivotal between a bolt closed position and a bolt open position;
a detent (32) journalled on the housing (12, 14, 16) and pivotable into engagement with the fork bolt (30) to latch the fork bolt in the bolt closed position;
an unlatching lever (44) pivotally attached to the housing for pivotal movement between a latched position and an unlatched position;
a locking lever (40), with a slot (41), pivotally attached to the housing (12, 14 and 16) for pivotal movement between a locking lever locked position and a locking lever unlocked position;
an intermittent lever (34), with a tab (48), pivotally attached to the detent (32) and having a pivot pin (38) that is received in the slot (41) in the locking lever (40) and wherein the tab (48) is in a path of movement of the unlatching lever (44) when the locking lever (40) is in the locking lever unlocked position and the tab (48) is out of the path of movement of the unlatching lever (44) when the locking lever (44) is in the locking lever locked position; and
a cam surface (152) on the fork bolt (30) that contacts the detent (32) upon rotation of the fork bolt (30) from the bolt open position to the bolt closed position, pivots the detent (32), moves a cam follower (160) of the intermittent lever into contact with an unlatching lever cam surface (162) and pivots the locking lever (40) to the locking lever unlocked position.
2. A vehicle door latch (10) as set forth in claim 1 wherein the intermittent lever cam
surface (160) is a roller surface and the unlatching lever cam surface (162) is an
inclined generally flat surface.
3. A vehicle door latch (10) as set forth in claim 1 wherein pivoting the unlatching
lever (44) to the unlatched position moves the unlatching lever cam surface (162)
away from the intermittent lever cam surface (160).
4. A vehicle door latch 10 comprising:
a housing (12, 14, 16);
a fork bolt (30) journalled in the housing (12, 14, 16) and pivotable between a bolt closed position and a bolt open position;
a detent (32) journalled in the housing (12, 14, 16) and biased into engagement with the fork bolt (130) to latch the fork bolt (130) in the bolt closed position;
an unlatching lever (44) pivotally attached to the housing (12, 14, 16) for pivotal movement between a latched position and an unlatched position;
a locking lever (40), with a slot (41), pivotally attached to the housing (12, 14, 16) for pivotal movement between a locking lever locked position and a locking lever unlocked position;
an intermittent lever (34), with a tab (48), pivotally attached to the detent (32) and having a pivot pin (38) that is received in the slot (41) in the locking lever (40) and wherein the tab (48) is in the path of movement of the unlatching lever (44) when the locking lever (40) is in the locking lever unlocked position and the tab (48) is out of the path of movement of the unlatching lever (144) and the locking lever (40) is in the locking lever locked position;
a cam surface (152) on the fork bolt (30) that contacts the detent (32) upon rotation of the fork bolt (130) from the bolt open position to the bolt closed position, the cam surface having a radius that increases from a point (154) of initial contact with the detent to near a point (156) of final contact with the detent in which the fork bolt is in the closed position, the cam surface pivoting the detent upon rotation of the fork bolt and moving (32), an intermittent lever roller cam surface (160) into contact with an unlatching lever cam surface (162) thereby pivoting the intermittent lever (134) relative to the detent (32) and pivoting the locking lever (40) to the locking lever unlocked position.
5. A vehicle door latch (10) as set forth in claim (4) wherein pivoting the unlatching
lever (144) to the unlatched position moves the unlatching lever cam surface (162)
away from the intermittent lever roller cam surface (160).
6. A vehicle door latch (10) operating method comprising:
locking the vehicle door latch (10) that is in an unlatched position;
moving the vehicle door latch to a unlatched position;
moving a cam surface (152) on a fork bolt (130) into contact with a detent (32);
pivoting the detent (32) by continuing rotation of the fork bolt (130) and the cam surface on the fork bolt (30);
moving an intermittent lever (134) that is pivotally attached to the detent (32) away from the fork bolt (30);
pivoting the intermittent lever (34) relative to the detent (32); and
pivoting a locking lever (40) through a connection between the intermittent lever (134) and the locking lever (40), to an unlocked position of the locking lever (40).