US3170722A

US3170722A - Latch mechanism

Info

Publication number: US3170722A
Application number: US202189A
Authority: US
Inventors: Charles E Schutte
Original assignee: Ford Motor Co
Current assignee: Ford Motor Co
Priority date: 1962-06-13
Filing date: 1962-06-13
Publication date: 1965-02-23
Anticipated expiration: 1982-02-23
Also published as: DE1918123U

Description

Feb. 23, 1965 c. E. scHuTTl-:r

LATCH MECHANISM 2 sheets-sheet L Filed June 15, 1962 cid' INVENTOR.

C. E. SCHUTTE LATCH MECHANISM Feb. 23, 1965 Filed June 1s, 1962 2 Sheets-Sheet 2 INVENTOR.

This inventionrelates to latch mechanisms and more particularly to such mechanisms as applied toluggagc compartment closures or'the like on vehicle bodies.

The conventional luggage compartment latch mechanism comprises a combination dovetail-housing partially enclosing a latch element having a keeper engaging por- "tion 'projecting from the housing. The latch element is releasably held in latched position by some form vof a detent. Disengagement ofthe detent from the latch element is accomplished through a system of levers arranged to multiplyV the turning force exerted on a key inserted in a key cylinder mechanism. The latch mechanism usually incorporates suitable Asprings which function to yieldably hold/the mechanism partis in predetermined positions or to restore the-parts to their original positions after the latch mechanisrhhas been operated. s

An important factor in the acceptability vof such mechanismsfor commercial use is the degree of key torquerequired to turn thekey to cause operation of the system f levers for disengaging the detent from the latch element.l The number and placement of the springs used in the mechanism has ajdirect bearing on the amount of torque which must be applied to the key to operate the latch mechanism. l

i' The construction and arrangement of the latch mechanismY embodying the present invention has the particular advantage that only one spring is utilized to perform the necessary functions of yieldably holding thelatch mechanism elements in predetermined positionsand ofV restoring elements of the lever` systemand the latch elementto suchV predetermined positions after actuation 'of the latch mechanism by operation of a -key operated locking and unlocking''device. The abfility of the single spring to per- `form its vmultiple functions is derived from the. pivotalI relationship of a detent carrying ,lever and of` theV latch element and of the relationship of a detenton `the detent carrying leverand a detent engageable portion of the latch element. These relationships arel such that: (1) When the latch'element is 'inolatched position the detent is engagedwith `the detent engageable portion to hold the latch element against movement in unlatching direction, and-(2) when the latch elementis in unlatched position the detentyieldingly abuts the detent engageable portion to holdthe latch element in unlatched position. l' o l It is an object of the present invention to provide a simplefcompact, eicient and economical latch mecha.-` nism which `vvillmeet all durability'and operational requirements'particularly forVl use on automotive vehicles.`

Other objects and advantages'of the present invention Willbe made more apparent as this description proceeds, particularly when considered in connection withtheaccompanying drawings, wherein: i o

FIG. 1 is a 'front elevational view of a latch mechanism constructed in accordance with the present invention, a

portion of the housing cover ,plate being cut away to ex- 'pose the vcomponents of the latch mechanism as they ap-Y pear with the latch element in unlatched position;`

FIG. 2 is a view in part similar-to FIG. 1 illustrating the componentsrof the latch mechanism in lfatched'position;`

FIG; Sis" anenlargedside elevational view looking in the direction of the arrow 3 in FIG. 1; and

. FIG'. 4 is an enlarged sectional view taken substantiallyl on theline 4L-4 of FIG?.` 1.1

United States Patent 0 The drawings illustratethe latch mechanism, generally designated 11, asit would appear when applied tothe luggage compartment door of an automobile body, but it will be understood that the device is also applicable to other doors and closure members.

The latch mechanism 11 comprises a substantially rectangular housing or casing, generally designated 12. In the installed position of the `latch mechanism on a vehicle compartment door or deck lidv closure structure, the longitudinal. axis of its housing or casing 12 extends ina substantially up and` down direction.` The housing or casing V12 has van integral inner or rear Wall 13, sidev '1 `he outer or front wall 18, or the one in spaced rel a-` v t1onsh1p to thewall 13, is an elongated cover plate which is secured in position to complete the housing after the assembly of the latch mechanism components within the housing or casing 12.` vIt will be noted that the

side walls

14 and 15 are tapered at their bottom ends (see FIGS. 2 and 3), for a purpose to be more fully explained.

Both'the housing 12 and the cover plate 18 are provided with complementary flanges or

ears

21 and 22, respectively, extending laterally from the sides thereof at the vupper end of each. The llanges are provided with aligned apertures 23 adapted to receive bolts (not shown) or the like for mounting .the latch mechanism on the closure structure. plate to the housing, the

.anges

21 and 22, respectively, are spot welded to each other.

The operating components ofthe latch mechanism 11 AThe lever 24 is an elongated memberwhich is pivotally mounted against the inner face 31 of the inner or rear Wall 13 of the housing. `As best` seen in FIG." 4, lever t 24 is mounted on a reduced diameter shoulder portion 32 of pivot shaft 28. `The pivot shaft'28 has a further reduced end portion 33 which projects through a hole in the inner.` Wall 13 of the housing and is riveted or staked over as Indicated at 34 for permanent lattachment to the housing. The pivot shaft` 28 at its other endjhas `an `extension 35 adapted to project through a suitableaperture A `V1n 'the cover plate 13 and then to lbe riveted or stakedA t over at 36. This, of course, is'done after the latch mechanism-components have been assembled withinthe housing.

i The spring 26 yieldably urges the lever 24in a clockwise direction as viewed FIGSQl and 2. The-spring 26 is a coil lspringwhich encompasses the pivot stud 28.V It has-two upstanding

free end portions

37 and 38. The

end portion 37 of the spring 26 lies against the inner surface of the side Wall 14 and the end portion 38 hooks over Y the edge-of -the lever 24 contiguous to the side-wall 14. Y

The spring 25'is'installedin a preloaded condition.

The latch element 25 comprises a plate member which is pivotally mounted on the shoulder `stud or pivot shaft 'i 29. It will be noted thatrthe latchelement is mountedlinVV i centrally spaced relationship to the inner and outer Walls of the housing. Asp'acer 39 maintains vthe latch element `in properly spaced-,relationship to the inner wall and a shoulder 41 `on the pivot shaft 29 maintains the proper spaced relationship tothe outerwall. The pivotv shaft 29y miam-I Patented Penas, i965 In the iinal assembly of the cover l 3 ends are staked or riveted over at 34 and Se, respectively, as were the ends of the shaft 27.

The latch element 25 is provided at one side of its pivot axis with spaced

ingers

42 and 43. At its opposite side it is provided with an abutment or projection 44 having on one side thereof a shoulder 45 and on the other side thereof a cam surface 45. The latch element 25 is provided with a further abutment or extension 47 which in unlatched condition of the latch` mechanism, see FIG. 1, engages the side wall of the casing to act as a stop limiting the direction of movement of the latch element in unlatched direction or, as viewed in FG. 1, in a clockwise direction.

Intermediate its ends the lever 24 is provided with an embossed portion 48 having a shoulder 49 thereon. The shoulder 49 may hereinafter be referred to as the detent on the lever 24 and the abutment 44 on the latch element may hereinafter be referred to as a detent engageable portion of the latch element. As was previously explained, the latch element is positioned substantially centrally of the

walls

13 and 18 and lthe lever 24 is mounted in surface contact with the inner wall 13 of the housing. The embossed portion 4S of the lever brings the detent 49 into a common plane with the latch element.

The upper end portion 51 of the lever 24 lies in a common plane with the lower end portion and has a ilange 52 which is turned in the direction ofthe cover` plate 18. The ange 52 isadapted'to be engaged by the lower free end 53 of the actuator cam 27. The actuator cam 27 is pivotally mounted on the cover plate by means of a tubular rivet 55 having a square or rectangular hole or aperture 56 through its center. This actuator cam is adapted to be operated by a conventional key cylinder mechanism (not shown) mounted in the outer panel of the closure or compartment on which the latch mechanism is mounted. It will be understood that the key cylinder mechanismincludes a shaft (not shown) which passes through the aperture 56 in the latch actuating cam tubular rivet. A

As seen in FIGS. l and 2, the spaced

fingers

42 and 43 which form the latching portion of the latch element project through an aperture 54 in the side wall 15 of the housing or casing 12.

The latch mechanism is adapted to have latching engagement with any suitable striker device which may be mounted on the floor or lowerpanel of a compartment in any desired manner. As far as the present latch mechl' anism is concerned, theV striker is required to havean upper wall portion 57, a fragmentary portion of which is illustrated in the drawing, having an aperture therein which at one side is defined by a downwardly turned flange 58 and at the other side by an inwardly. and downwardly turned flange 59. As shown in FIG. 2, the tapered portions of the housing or

casing side wallsA

14 and 15 will enter the aperture in the striker wall 57 and act as a pilot to center the latch mechanism with respect to the striker and thereby the closure with respect to the opening in the compartment.

As seen in FIG. 1, in unlatched position the latch element finger 42 iswithin the confines of the side wall 15 of the housing. The latch element finger 43 lies outside of the contines of the side wall 15 of the housing 12 and is adapted to engage the upper surface of the striker'. Upon downward movement of the housing into the striker aperture, the engagement of the linger 43 with the upper surface of the striker causes the latch elementfto be rotated in a clockwise direction. As was pointed outlabove, the spring 26 urges the lever 24 in a clockwise direction toward the latch element 25. As the latch element rotates in a counterclockwise direction, the lever 24 is forced slightly to the left or in a counterclockwise direction until the detent 49 thereon is able first to surmount the cam surface 46 of the abutment on the latch element 25 and then to dropinto engagement with` the shoulder 45 of the latch element. As soon as this occurs, the latch ele- A 4 ment 25 is held against rotation in a clockwise direction by the detent 49 on the lever 24. The compartment closure is then latched to the compartment wall.

in order to unlatch the latch mechanism, the actuator cam 27 must be swung in a clockwise direction, by actuation of a key cylinder mechanism as previously described, so that its cam portion'53 will engage the'upper end of the lever 24 to urge the latter in a 'counterclocka wise direction against the resistance of the spring V26. As soon as the detent portion of the lever 24 is moved Suthciently to the left, or away from the pivot axis of the latch element, the latch element is free to rotate, in av clockwise or unlatching direction.

It should be noted that most compartment,closures'l are mounted on hinge structures which include torsion barsor other suitable counterbalance means which are effective to cause immediate upwardA movement of the closure.;

as soon as the latch element is released. This upward movement is usually enough toA cause withdrawal of the latch mechanism suiciently above the` plane ofthev striker and rotation of the. latch element to a position in which the detent cannot reengage the shoulder on the latch element.

As soon as the actuator cam 27 isl released, that is, as

soon as the key actuating mechanism is no longer being twisted in a directionA to swing the actuator cam 27 in aclockwise direction, the springr26 exerts force on the lever 24 to urge the latter in a clockwise direction. However, one side of the detent on the lever 24 is now abutting the cam surface 46 on the latch element 25. Thus, the` force ofthe spring tending to urge the lever 24 in a clockwise direction is also applied to the latch element 25 through the abutting relationship of the detent 49 and thecam surface 46 of the abutment on the latch element. As best seen in FIG. 1, the point of contact betweenhthe detent and the cam surface 456 in unlatched position of the latch element 25 lies on a line passing above the center of the pivot shaft 29. The resultant force couple on the latchV element is one which urges the latch element in a clock'- wise or unlatching direction-at least to the extent permitted by the stop abutment 47. In latched condition of the latch mechanism the point of vcontact between the v detent 49 and the shoulder 45 on the latch element 25 results in a reaction force'which lies substantially on a line passing between the pivot axesV of the latch element 25 and the lever 24. AThe force couple acting` on the.

latch element in latched condition issuch that the latch element isactually being urged in a counterclockwise direction or latching condition. Of course, the latch element and the lever being nonfyieldablev elements,- the latch elementl is satisfactorily heldin latched position as a result of the engagement of the detent 49 with the shoulder 45.

Because of the relationship of the pivot centers as dctermined by the pivot axes of the

pivot shafts

28 and 29, and because of the relationship ofthe detent.. 49.of the lever 24 with respect'to the abutment 44 on the latch element, only the single spring 26-,is required to maintain thev latch element in unlatched position in readiness for latching engagement with the striker andto hold the lever 24 so that its detent 49 is in readiness .to engage the shoulder 45 0n the latch element when the latter is rotated into latching position after engagement with the striker. Because of: the mechanical advantage obtained'by the fact that the spring acts on a shorter length of the lever 24 than does the actuator cam 27, the resistance of the` actu'ating cam to being turned by the key is relatively low.

This provides the desirable low key torque which is an important criteria of a satisfactory luggage compartment latch mechanism. L

but that various changes and moditicationsamay be made without departing from the spirit` and scope of the invcntion as defined in the appended elaimsjl vergent and being adapted to act as pilot means for Y guiding saidlatch mechanismlinto latching position relative to a keeperV device,

an elongated lever pivotally mounted at one of its ends Y at said one /endof said housing for swinging movement about a pivot axis intersecting said support',

walls,

said lever extending longitudinally of said housingV along one of said side walls, i

a latch element pivotally mounted-within said housingY betweensaid elongated lever' and the other of said side walls for swinging movement about a pivot axis located intermediate the ends ofsaid housing and parallel to said lever pivot axis.

said latch element having a keeper engaging portion at one side thereof projecting through an aperture in said other side Wall of said housing, a detent on said elongated lever intermediate the ends and on the side thereof toward said other side Wall, an abutment on said latch element on the side thereof opposite said keeper engaging portion and in` opposing relation to said detent.

spring means urging said elongated lever and thereby said detent toward said other side wall into abutting lrelation to said latch element abutment,

and an outer manually operabley means pivotally mounted on one of said support walls at the other end of said housing engageable with the other end of said elongated lever to swing the same and there- Y by said detent portion out of latch element holding position. Y

' 2. A latch mechanism comprising:

an elongated housing having spaced support walls and side walls therebetween, said side walls at one end of said housing being convergent and being adapted to act as pilot means for guiding said latch mechanism into latching position relative to a keeper device,

an elongated l'ever pivotally mounted at one of its ends s said latch element having a keeper engaging portion at one side thereof projecting through an aperture in said other side wall of said housing,

a detent'portion on said elongated lever intermediate I the ends and onl the side thereof toward said other side wall, Y t an abutment on said latch element on the side thereof opposite said keeper engaging portionand in opposing relation tosaid detent portion, t said detent portion being engageable with one side of said latch element abutment to hold said latch element in latched position and with another side of said vabutment in unlatched position of said latch element, spring means urging said elongated lever in a direction toV position said detent portion in abutting relation to either side of said abutment,

, the pivotal relationship of lsaid lever and said latch element and the relationship of said detent portion and said one side of said abutment whensaid latch element is in latched lposition beingsuch that the'fo'rce t exerted by said detent portion on said abutment'acts latch element pivot axis and between the lever and latch element pivot axes. 1

' 3. Alatch mechanism comprising:l v y. `an elongated housing having-spaced supportwalls .and side walls therebetween,` a said side Walls at one endf'of said housing being convergent and being adapted to act as pilot means for guidingsa'id latch mechanism intolatching position'relaj tive toakeeper device,\ 5'

an elongated lever pivotally mounted at one of its ends `at said one end of said housing for swinging movement about `a pivot axis .intersecting 7 said support Walls, l said leverrextending longitudinally of said housing adjacent one of said side walls, f a latch element pivotally mounted Within said housing between said elongated lever and the other of said side walls for swinging movement about a pivot axis located intermediate the ends of said housing and paralf lel to said lever pivot axis,

said latch element having a keeper engaging portion at one side thereof projecting through an aperture in said other side Wall of said housing,

a detent portion on said elongated lever intermediate the ends and on the side thereof toward said other side wall,

an abutment on said latch element on the side thereof opposite said keeper engaging portion and in opposing relation to said detent portion,

`said detent portion being engageable `with one side of said latch element abutment to hold said latch element in latched position and with another side of said abutment in unlatched position of said latch element,

spring means urging said elongated lever in a direction to position said detent portion in abutting relation to either side of said abutment,

the pivotal relationship of said lever and said latch ele- 'Y side of said abutment whenl s aid'latch element is held in unlatched position being such that the force exerted by said detent portion on said abutment acts -substantially along a line passing to the other side of said latch element pivot axis. v

4'. A latch mechanism comprising:

an elongated housing having spaced support walls and side walls therebetween, Y

said side walls at one end ofA said housing being convergent and being adapted to act as pilot means for i Y guiding said ,latch mechanisminto latching position relative to a keeper device, 7 Y

an elongated lever pivotally'mounted at one of its ends at one end of said housing for swingingfmovement about a pivot axisintersecting said support walls,

said lever extending longitudinally of said housing adjacent one of said side walls,

a latch element pivotally mounted within said housing between said elongated lever and the other of said side Walls for swinging movement about a pivot axis located. intermediate lthe ends of said housing and parallel to said lever pivot axis,

said latch `element having a keeper engaging portion at one sidethereof projecting through an aperture in said' other side Wall of said housing, j

a ydetent portion on said elongated lever intermediate the ends and Von the side thereof toward said other side wall,

an abutment `on said latch element on the side thereof opposite said keeper engaging portion and in opposing relation totsaiddetent portion,

said detent portion being engageable with one, side of said latch element abutment to hold said'latch element in'latched position and With another side'of said abutment in unlatched position of said latch-element,

spring means urging said elongated lever in a direction to position said detent in abutting relation toeither side of said abutment,`

the pivotal relationship of said'lever and said'latchfelement and v t f (1) the relationship of said detent portiony and said one side of said abutment being such that when said latch element is in latched position said detent portion holds said latch element against movement in unlatehing direction, and

' outer manually operable means pivotally mounted on one (2) the relationship of said detent and said other side of said abutment being such that'when said latch element is in uulatched position said detent yieldingly holds said latch element in said unlatched position.

5. A latch-mechanism according to claim 4 having an or said support walls for engagement with the other end of said elongated lever to swing the same out of latch element holding position.

References Cited in the le of this patent UNITED STATES PATENTS 560,888 Ayars May 26, 1896 2,393,647V Marple Jan. 29, 1946 2,544,682 Hilgeman Mar. 13., 1951 3,016,968 Lenz et al Jan. 16, 1962

Claims

1. A LATCH MECHANISM COMPRISING: AN ELONGATED HOUSING SPACED SUPPORT WALL AND SIDE WALLS THEREBETWEEN, SAID SIDE WALLS AT ONE END OF SAID HOUSING BEING CONVERGENT AND BEING ADAPTED TO ACT AS PILOT MEANS FOR GUIDING SAID LATCH MECHANISM INTO LATCHING POSITION RELATIVE TO A KEEPER DEVICE, AN ELONGATED LEVER PIVOTALLY MOUNTED AT ONE OF ITS ENDS AT SAID ONE END OF SAID HOUSING FOR SWINGING MOVEMENT ABOUT A PIVOT AXIS INTERSECTING SAID SUPPORT WALLS, SAID LEVER EXTENDING LONGITUDINALLY OF SAID HOUSING ALONG ONE OF SAID SIDE WALLS, A LATCH ELEMENT PIVOTALLY MOUNTED WITHIN SAID HOUSING BETWEEN SAID ELONGATED LEVER AND THE OTHER OF SAID SIDE WALLS FOR SWINGING MOVEMENT ABOUT A PIVOT AXIS LOCATED INTERMEDIATE THE ENDS OF SAID HOUSING AND PARALLEL TO SAID LEVER PIVOT AXIS. SAID LATCH ELEMENT HAVING A KEEPER ENGAGING PORTIONM AT ONE SIDE THEREOF PROJECTING THROUGH AN APERTURE IN SAID OTHER SIDE WALL OF SAID HOUSING, A DETENT ON SAID ELONGATED LEVER INTERMEDIATE THE ENDS AND ON THE SIDE THEREOF TOWARD SAID OTHER SIDE WALL, AN ABUTMENT ON SAID LATCH ELEMENT ON THE SIDE THEREOF OPPOSITE SAID KEEPER ENGAGING PORTION AND IN OPPOSING RELATION TO SAID DETENT. SPRING MEANS URGING SAID ELONGATED LEVER AND THEREBY SAID DETENT TOWARD SAID OTHER SIDE WALL INTO ABUTTING RELATION TO SAID LATCH ELEMENT ABUTMENT, AND AN OUTER MANUALLY OPERABLE MEANS PIVOTALLY MOUNTED ON ONE OF SAID SUPPORT WALLS AT THE OTHER END OF SAID HOUSING ENGAGEABLE WITH THE OTHER END OF SAID ELONGATED LEVER TO SWING THE SAME AND THEREBY SAID DETENT PORTION OUT OF LATCH ELEMENT HOLDING POSITION.