US3692343A

US3692343A - Closure latch

Info

Publication number: US3692343A
Application number: US49289A
Authority: US
Inventors: Barthold F Meyer
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1970-06-24
Filing date: 1970-06-24
Publication date: 1972-09-19
Anticipated expiration: 1989-09-19

Abstract

A latch for a vehicle body closure, the latch including a latch bolt, a detent lever, means frictionally resisting movement of the detent lever and a transfer lever operable to overcome the friction and move the detent lever into and out of a detenting position against the latch bolt. A control pin on the latch bolt engages the transfer lever during movement of the latch bolt from an unlatched to a latched position to actuate the transfer lever and initiate simultaneous movement of the detent lever to the detenting position, the aforementioned friction functioning to maintain the detent lever in the detenting position.

Description

United States Patent Meyer CLOSURE LATCH [72] Inventor: Barthold F.'Meyer, Mt. Clemens,

[58] Field of Search ..292/2l0, DIG. 24, DIG. 26, 292/280, 216, 198, 204

[56] References Cited UNITED STATES PATENTS 199,685 1/1878 Bergman ..292/2l0 2,644,707 7/1953 Dall ..292/2l6 [451 Sept. 19, 1972 Pickles ..292/280 Johnstone ..292/2l0 X [57] ABSTRACT A latch for a vehicle body closure, the latch including a latch bolt, a detent lever, means frictionally resisting movement of the detent lever and a transfer lever operable to overcome the friction and move the detent lever into and out of a detenting position against the latch bolt. A control pin on the latch bolt engages the transfer lever during movement of the latch bolt from an unlatched to a latched position to actuate the transfer lever and initiate simultaneous movement of the detent lever to the detenting position, the aforementioned friction functioning to maintain the detent lever in the detenting position.

3 Claims, 7 Drawing figures PNENTEDSEP 1 9 m2 SHEET 1 0F 2 whowfii er 12 .4%

A TORNEY PHENTEDSEHQ 1912 3.692.343

sum 2 UP 2 I NVENTOR.

BY 5arfho/d .51 Meyer ATTORNEY- CLOSURE LATCH This invention relates generally to vehicle body closures and in particular to a positive acting closure latch for releasably securing a vehicle body closure in a closed position.

' A particular type of closure latch used extensively on automobile doors is known to employ a bifurcated latch bolt for engaging and capturing, in the closed position of the door, a striker rigidly mounted on the vehicle body. Typically, a cam or cam edge defining at least one detent shoulder is rotatable as a unit with the latch bolt and is engaged by a detent lever which is constantly urged against the cam edge so as to drop behind the detent shoulder when the latch bolt achieves a latched position thereby to prevent a reverse or unlatching movement of the latch bolt. Ordinarily, spring means are employed to constantly urge the detent lever toward the detenting position behind the cam detent shoulder. This invention, however, substitutes for the usual detent lever and detent lever biasing spring an arrangement for mechanically positioning the detent lever in either the detenting or a releasing position and means frictionally engaging the detent lever and preventing movement thereof in the absence of an externally applied motivating force.

The primary feature of this invention is that it provides anew and improved closure latch for a'vehicle body closure, the latch including a latch bolt engageable in a latched position on a striker and detent means operable in a detenting position to prevent unlatching movement of the latch bolt, the detent means being frictionally maintained in either the detenting or in a releasing position. Another feature of this invention resides in the provision in the closure latch of detent control means responsive to closing movement of the closure to mechanically position the detent means in detenting position in the closed position of the closure. Yet another feature of this invention resides in the provision in the closure latch of detent assist means responsive to closing movement of the closure to convert a portion of the kinetic energy thereof into potential energy, the latter being selectively releasable to assist in moving the detent means from the detenting to the releasing position. A still further feature of this invention resides in the provision in the closure latch of an intermediate transfer lever engageable with the detent means and cooperating in a detent operating or first functional mode with a projection on the latch bolt to mechanically position the detent means in the detenting position in response to movement of the latch bolt to the latched position and cooperating in a release assist or second functional mode with spring means to transfer to the latter for conversion to potential energy a portion of the kinetic energy of the closure, the intermediate transfer lever thereafter being operable in response to release of the potential energy of the spring means to move the detent means from the detenting to the releasing position.

These and other features of this invention will be readily apparent from the following specification and from the drawings wherein:

FIG. 1 is a fragmentary side elevational view of an automobile vehicle body having a closure latch according to this invention;

FIG. 2 is an enlarged view taken generally along the plane indicated by lines 22 in FIG. 1 and showing the closure latch in unlatched condition;

FIG; 3 is a partially broken away view taken generally along the plane indicated by lines 3-3 in FIG. 2;

FIG. 4 is an exploded perspective view of the closure latch according to this invention;

FIG. 5 is similar to FIG. 2 but showing the closure latch in fully latched condition;

FIG. 6 is similar to FIG. 2 but showing thev closure latch in intennediate latched condition; and

FIG. 7 is similar to FIG. 5 but showing the intermediate transfer lever in position to initiate movement of the detent lever from the detenting to the releasing position.

Referring now to FIG. l-of the drawings, an automobile type vehicle body generally designated 10 includes a right front fender structure 12, a right rear quarter panel structure 14 and a roof structure 16. The front fender structure and rear quarter panel structure combine below the vehicle belt line 18 to define an access opening in the vehicle body adapted to be closed by a closure or front door 20 vertically hinged on the vehicle body generally at the forward edge of the access opening for swinging movement between an open position, not shown, and a closed position, FIG. 1. A striker 22 is rigidly secured to the rear jamb of the access opening and in the closed position of the door 20 is received within a closure latch 24 according to this invention mounted on door 20.

With particular reference to'FIGS. 2 and 3 of the drawings, the closure latch 24 includes a generally L- shaped base plate 26 having a short leg 28 and long leg 30 with a striker clearance slot 32 formed therein. The base plate 26 is rigidly secured to the door 20 between inner and outer panels thereof, not shown, with clearance slot 32 opening toward the interior of the vehicle body in the closed position of the door and registering with a similarly shaped aperture in the rear edge, not shown, of the door.

As best seen in FIGS. 2 and 4, a rivet 34 rigidly secured to long leg 30 of the base plate 26 generally adjacent the clearance slot 32 rotatably supports a bifurcated latch bolt 36 rigidly supporting a pair of spaced control pins 44 and 4S and having a throat portion 38 and a cam edge 40 defining a pairof

detent shoulders

42 and 43. The latch bolt 36 is rotatable between an unlatched position, FIG. 2, and either an intermediate latched position, FIG. 6, or a fully latched position, FIGS. 5 and 7. A coil torsion spring, not shown, is supported on rivet 34 with one end engaging the latch bolt 36 and the other end engaging the base plate 26 to thereby bias the latch bolt counterclockwise toward the unlatched position.

As best seen in FIG. 4, a detent lever 46 is provided to releasably maintain the latch bolt in either of the intermediate and the fully latched position, the detent lever having a circular aperture 48 therein and including a detent leg 50, an upturned tab 52, and a stop projection 53. A rivet or stud 56 of diameter generally equal to the diameter of detent lever aperture 48 is tightly received within the latter and mounts the detent lever on the base plate for rotary movement in a plane generally parallel to long leg 30 of the base plate. Substantial friction is generated between the shank of the rivet and the edge of aperture 48, however, and effectively resists rotation of the detent lever in the absence of a significant motivating force applied to the latter; In

the mounted position on rivet 56, the detent lever lies in generally co-planar relation to the latch bolt 36 with stop projection 53 being situated between apair of spaced upturned tabs 57 on long leg 30 of the base plate. The tabs 57 function to limit forced rotary movement of the detent lever in a counterclockwise direction to a detenting position, FIGS. 5, 6 and 7, wherein detent 50 engages either one of

detent shoulders

42 and 43 on the latch bolt and in a clockwise direction to a releasing position, FIG. 2, wherein detent 50 is remote from the latch bolt.

Referring now to FIGS. 2 and 4, the rivet 56 is freely received within an elongated aperture 58 in an intermediate transfer lever 60 and supports the transfer lever on the base plate .26 for pivotal movement and for bodily shiftable movement in a plane generally parallel to the plane of detent lever 46. The transfer lever 60 has integral therewith a downturned spring tab 62, a downturned driving tab 64, a downturned lifting tab 66 and a depending leg 67 terminating in an upturned bearing tab 68. As best seen in FIGS. 2 and 5, the transfer lever 60 is supported on rivet 56 in overlying relation to detent lever 46v with lifting tab 66 underlying tab 52 on the detent lever, driving tab 64 generally overlying the upper marginal edge of the detent lever and depending leg 67 overlying latch bolt 36. The transfer lever is rotatable about the rivet 56 generally between a retracted position, FIG. 2, corresponding to the releasing position of the detent lever 46 and an extended position, FIGS. and 6, corresponding to the detenting position of the detent lever 46. A coil tension spring 70 has one end engaging spring tab 62 on the transfer lever 60 and the other end engaging a pin 72 projecting from long leg 30 of the base plate. The spring 70 biases the transfer lever 60 clockwise toward the retracted position thereof and resiliently maintains the upper edge of aperture 58 in contact with the shank of rivet 56, FIG. 2.

Referring particularly now to FIGS. 2 and 4, a rivet 74 rigidly projecting from long leg 30 of the base plate is loosely received within a slot 76 in an operating lever 78 thereby supporting the latter on the base plate for rotary and bodily shiftable movement in a plane parallel to the planes of the latch bolt 36 and the transfer lever 60. The operating lever 78 has a rigid lifting pin 82 projecting therefrom and in the mounted position of the operating lever on the rivet 74 the lifting pin underlies bearing tab 68 on the transfer lever while the distal end of the operating lever protrudes through a slot 86 in the short leg 28 of the base plate, FIG. 3.

Referring particularly now to FIGS. 1, 2 and 3, a simplified link and lever arrangement is shown for actuating the operating lever 78 and includes an L-shaped lever 88 rotatably supported on short leg 28 of the base plate at 90. One leg of the lever 88 underlies the distal end of operating lever 78 while the other leg thereof is connected to an inside operating handle 92 bya draft link 94. A second draft link 96 has one end pivotally connected to the first mentioned leg of lever 88 at 98 and the other end operably connected to an exterior push button assembly 100. Through the

draft links

94 and 96, operation of either inside handle 92 or push button assembly 100 functions to rotate the lever 88 clockwise, FIG. 3, thus initiating clockwise pivotal movement, FIG. 2, of the operating lever 78 for a purpose to be described hereinafter.

When the door 20 assumes the open position, the latch bolt 36 normally occupies the unlatched position while the detent and the transfer levers 46 and 60 assume the releasing and retracted positions, respectively, FIG. 2. Referring now to FIGS. 2 and 6, as the door 20 is brought toward closed position, the latch bolt 36 engages the striker 22 in the throat portion of the former. As the bolt engages the striker, the kinetic energy or inertia of the closing door causes the striker to initiate clockwise rotary movement of the latch bolt bringing the control pin 45 on'the latter into engagement with a side edge of depending leg 67 of the transfer lever. Subsequent to such engagement and upon continued clockwise rotary movement of the latch bolt, the pin 45 initiates counterclockwise rotary movement of the transfer lever 60 about rivet 56 from the retracted position, FIG. 2, to the extended position, FIG. 6. Simultaneously, driving tab 64 -engages the upper edge of detent lever 46 and initiates counterclockwise movement of the latter from the releasing to the detenting position behind detent shoulder 43 on the latch bolt when the latter achieves the intermediate latched position. The detent 50 thus maintains the latch bolt in the intermediate latched position, FIG. 6, while the detent lever 46 is positively maintained in the detenting position by the aforementioned friction between the edge of circular aperture 48 and the shank of rivet 56 and the transfer lever 60 is held-in the extended position against spring by control pin 45 on the latch bolt.

Normally, the kinetic energy of the closing door will be sufficient to continue rotary movement of the latch bolt beyond the intermediate latched position to the fully latched position. Such movement of the latch bolt initiates a second sequence of simultaneous movement of both the detent lever and the transfer lever. First, referring to FIGS. 5 and 6, as the latch bolt is rotated from the intermediate to the fully latched position the detent 50 slides over the cam edge 40 of the latch bolt between the

detent shoulders

42 and 43, the cam edge camming the detent lever clockwise, FIG. 6, out of the detenting position against the friction at rivet 56. Simultaneously, the control pin 45 exerts an increasing force on the side edge of depending leg 67, the latter force being resisted by a force reaction between driving tab 64 and the upper edge of the detent lever at the point of contact therebetween. These two opposing forces impose a counterclockwise force couple on the transfer lever which rotates the transfer lever counterclockwise, FIG. 6, about the point of engagement between driving tab 64 and the detent lever until the control pin 45 passes beneath the bearing tab 68, the aforementioned rotation being accommodated relative to the base plate 26 by slot 58 in the transfer lever. As the control pin 45 passes beneath the bearing tab, the spring 70 forces the upper end of slot 58 back against the rivet 56 while the second control pin 44 simultaneously engages the side edge of depending leg 67 of the transfer lever thereby initiating counterclockwise rotation of the latter, FIGS. 5 and 6. As the latch bolt approaches the fully latched position, the control pin 44 rotates the transfer lever to the extended position against spring 70 while driving tab 64 on the transfer lever simultaneously rotates the detent lever into the detenting position behind detent shoulder 42 on the latch bolt when the latter achieves the fully latched position. The detent 50 thus maintains the latch bolt in the fully latched position, FIG. 5, while the detent lever 46 is positively maintained in the detenting position by the aforementioned friction at rivet 56 and the transfer lever 60 is held in the extended position against spring 70 by control pin 44 on the latch bolt.

When release of the latch from either the fully or the intermediate latched conditions is desired to permit opening movement of the door, either the door handle 92 or the push button assembly 100 is manually actuated to initiate clockwise rotation of the L-shaped lever 88, FIG. 3. As the lever 88 rotates, the leg thereof underlying the operating lever 78 contacts the latter and initiates clockwise rotation thereof, FIG. 5, bringing lifting pin 82 into engagement with the lower surface of bearing tab 78 on the transfer lever. The force exerted on transfer lever 60 by lifting pin 82 is resisted by a force reaction between the tab 52 on the detent lever and the lifting tab 66 on the transfer lever. These two opposing forces impose a counterclockwise force couple, FIGS. 5 and 6, on the transfer lever which rotates the latter counterclockwise about the point of contact between tab 52 and lifting tab 66 until bearing tab 68 overlies control pin 44, FIG. 7. Immediately upon reaching this position, the restraint provided by the control pin is removed from spring 70-and the latter rapidly rotates the transfer lever clockwise, FIG. 7, from the extended to the retracted position, the lifting tab 66 on the transfer lever simultaneously moving the detent lever from the detenting to the releasing position thereby to release the latch bolt for movement from either latched position to the unlatched position.

From the foregoing description, it will be apparent that the spring 70 functions only to reduce the effort necessary to unlatch the door. Should failure of spring 70 occur while the detent lever 46 is in the detenting position, the friction at the rivet 56 would permit no change in the position of the detent lever and the door would remain securely latched. The only noticeable effect of the failure of spring 70 in the fully latched condition of the latch would be an increase in the effort required to unlatch the door. More particularly, with the 'spring 70 inoperative, the motivating force for rotating the transfer lever and detent lever out of the extended and the detenting positions, respectively, would have to be supplied directly by the lifting pin 82 on the operating lever 78. Due to the requirement that the lifting pin 82 now overcome the friction at rivet 56 in addition to lifting the bearing tab 68 over control pin 44, an increased effort at the push button 100 or handle 92 is necessary. This increased effort will, of course, be apparent to the operator and indicate to him that repair of the latch is necessary. Should the spring 70 fail while the latch is in the unlatched condition, closing movement of the door would initiate the normal latching sequence as described hereinbefore. Thus, it is apparent that the closure latch according to this invention remains fully operative regardless of the condition of the spring 70.

Finally, the latch is provided with a simplified arrangement for preventing unauthorized manipulation. More particularly, as best seen in FIGS. 1 and 5, conventional link and lever means, not shown, are arranged between an interior garnish button 102 and an exterior lock cylinder 104 and the operating lever 78.

When either the garnish button or lock cylinder is actuated,.the link and lever means function to bodily shift the operating lever leftwardly, FIG. 5, to a location, not shown, wherein the lifting pin no longer underlies the bearing tab 68 on the transfer lever so-that actuation of handle 92 or push button assembly results merely in freewheeling movement of the lifting pin past the bearing tab 68 and along side of depending leg 67.

Having thus described the invention, what is claimed 1. In a vehicle including a body member having an opening therein and a striker rigidly secured to one of said body member and a closure mounted thereon for movement between open and closed positions relative to said opening, a closure latch comprising a latch bolt, means mounting said latch bolt on the other of said body member and said closure for movement between a latched position capturing said striker in said closed position of said closure and an unlatched position releasing said striker, said latch bolt in said latched position thereof retaining said closure in said closed position, detent means movable between a detenting position engaging said latch bolt in said latched position of the latter and preventingmovement thereof towards said unlatched position and a releasing position remote from said latch bolt, friction means remote from said latch bolt frictionally engaging said detent means, said friction means being the sole means for maintaining said detent means in either of said detenting and said releasing positions, detent operating means responsive to movement of said latch bolt from said unlatched to said latched position to overcome said friction means and forcibly move said detent means from said releasing to said detenting position, and detent release means selectively operable to overcome said friction means and move said detent means from said detenting to said releasing position thereby to release said latch bolt for movement from said latched to said unlatched position thereof.

2. In a vehicle including a body member having an opening therein and a striker rigidly secured to one of said body member and a closure mounted thereon for movement between open and closed positions relative to said opening, a closure latch comprising a bifurcated latch bolt, means mounting said latch bolt on the other of said body member and said closure for pivotal movement between a latched position capturing said striker in said closed position of said closure and an unlatched position releasing said striker, said latch bolt in said latched position thereof retaining said closure in said closed position, a detent lever, means mounting said detent lever on said other of said body member and said closure for movement between a detenting position engaging said latch bolt and maintaining the latter in said latched position and a releasing position remote from said latch bolt, friction means remote from said latch bolt frictionally engaging said detent lever, said friction means being the sole means for maintaining said detent lever in either of said detenting and said releasing positions, an intermediate transfer lever, means mounting said intermediate transfer lever on said other of said body member and said closure for movement between extended and retracted positions, said intermediate transfer lever being engageable on said detent lever and being operable upon movement from said retracted to said extended position to overcome said friction means and move said detent lever from said releasing to said detenting position and upon movement from said extended to said retracted position being operable to overcome said friction means and move said detent lever from said detenting to said releasing position, means on said latch bolt and on said intermediate transfer lever responsive to movement of said latch bolt from said unlatched to said latched position to move said transfer lever from said retracted to said extended position, and release means selectively operable to move said transfer lever from said extended to said retracted position thereby to simultaneously move said detent lever from said detenting to said releasing position to release said latch bolt for movement from said latched to said unlatched position.

3. In a vehicle including a body member having an opening therein and a striker rigidly secured to one of said body member and a closure mounted thereon for movement between open and closed positions relative to said opening, a closure latch comprising a bifurcated latch bolt, means mounting said latch bolt on the other of said body member and said closure for pivotal movement between a latched position capturing said striker in said closed position of said closure and an unlatched position releasing said striker, said latch bolt in said latched position thereof retaining said closure in said closed position, a detent lever mounted on said other of said body member and said closure for movement between a detenting position engaging said latch bolt and maintaining the latter in said latched position and a releasing position remote from said latch bolt, friction means remote from said latch bolt frictionally engaging said detent lever, said friction means being the sole means for maintaining said detent lever in either of said detenting and said releasing positions, an intermediate transfer lever, means mounting said intermediate transfer lever on said other of said body member and said closure for movement between extended and retracted positions, said intermediate transfer lever being engageable on said detent lever and being operable upon movement from said retracted to said extended position to overcome said friction means and move said detent lever from said releasing to said detenting position and upon movement from said extended to said retracted position being operable to overcome said friction means and move said detent lever from said detenting to said releasing position, spring means biasing said intermediate transfer lever toward said retracted position thereof, a control projection rigidly secured to said latch bolt and engageable on said intermediate transfer lever during movement of said latch bolt from said unlatched to said latched position, said projection thereafter forcibly rotating said transfer lever against said spring means from said retracted to said extended position thereby to position said detent lever in said detenting position, and means selectively operable in said extended position of said transfer lever to disengage the latter from said control projection thereby to permit said spring means tomove said transfer lever from said extended to said retracted position, said transfer lever simultaneously moving said detent lever from said detenting to said releasing position thereby to release said latch bolt for movement from said latched to said unlatched position.

=0 t I! I

Claims

1. In a vehicle including a body member having an opening therein and a striker rigidly secured to one of said body member and a closure mounted thereon for movement between open and closed positions relative to said opening, a closure latch comprising a latch bolt, means mounting said latch bolt on the other of said body member and said closure for movement between a latched position capturing said striker in said closed position of said closure and an unlatched position releasing said striker, said latch bolt in said latched position thereof retaining said closure in said closed position, detent means movable between a detenting position engaging said latch bolt in said latched position of the latter and preventing movement thereof towards said unlatched position and a releasing position remote from said latch bolt, friction means remote from said latch bolt frictionally engaging said detent means, said friction meaNs being the sole means for maintaining said detent means in either of said detenting and said releasing positions, detent operating means responsive to movement of said latch bolt from said unlatched to said latched position to overcome said friction means and forcibly move said detent means from said releasing to said detenting position, and detent release means selectively operable to overcome said friction means and move said detent means from said detenting to said releasing position thereby to release said latch bolt for movement from said latched to said unlatched position thereof.

3. In a vehicle including a body member having an opening therein and a striker rigidly secured to one of said body member and a closure mounted thereon for movement between open and closed positions relative to said opening, a closure latch comprising a bifurcated latch bolt, means mounting said latch bolt on the other of said body member and said closure for pivotal movement between a latched position capturing said striker in said closed position of said closure and an unlatched position releasing said striker, said latch bolt in said latched position thereof retaining said closure in said closed position, a detent lever mounted on said other of said body member and said closure for movement between a detenting position engaging said latch bolt and maintaining the latter in said latched position and a releasing position remote from said latch bolt, friction means remote from said latch bolt frictionally engaging said detent lever, said friction means being the sole means for maintaining said detent lever in either of said detenting and said releasing positions, an intermediate transfer lever, means mounting said intermediate transfer lever on said other of said body meMber and said closure for movement between extended and retracted positions, said intermediate transfer lever being engageable on said detent lever and being operable upon movement from said retracted to said extended position to overcome said friction means and move said detent lever from said releasing to said detenting position and upon movement from said extended to said retracted position being operable to overcome said friction means and move said detent lever from said detenting to said releasing position, spring means biasing said intermediate transfer lever toward said retracted position thereof, a control projection rigidly secured to said latch bolt and engageable on said intermediate transfer lever during movement of said latch bolt from said unlatched to said latched position, said projection thereafter forcibly rotating said transfer lever against said spring means from said retracted to said extended position thereby to position said detent lever in said detenting position, and means selectively operable in said extended position of said transfer lever to disengage the latter from said control projection thereby to permit said spring means to move said transfer lever from said extended to said retracted position, said transfer lever simultaneously moving said detent lever from said detenting to said releasing position thereby to release said latch bolt for movement from said latched to said unlatched position.