US3491979A

US3491979A - Latch mechanism

Info

Publication number: US3491979A
Application number: US618681A
Authority: US
Inventors: Harry Wonell
Original assignee: HOWELL IND Inc
Current assignee: HOWELL IND Inc
Priority date: 1967-02-27
Filing date: 1967-02-27
Publication date: 1970-01-27
Anticipated expiration: 1987-01-27

Description

Jan. 27, 1970 H. WONELL LATCH MECHANISM Filed Feb. 27. 19s? INVENTOR HARRY WONELL BY M, M f/ H.| ,m m 'M 4 I as; 8

il mu. lilin'lym ATTORNEYS United States Patent O 3,491,979 LATCH MECHANISM Harry Wonell, Westland, Mich., assignor to Howell Industries, Incorporated, Detroit, Mich., a corporation of Michigan Continuation-impart of application Ser. No. 614,863, Feb. 9, 1967. This application Feb. 27, 1967, Ser.

Int. Cl. B60n 1/08 U.S. Cl. 248-430 22 Claims ABSTRACT OF THE DISCLOSURE A latch bar is a holder for a pair of members interconnected by a slide device for relative movement along a first axis each member having sidewall sections in parallel relationship. The latch bar is slidably disposed in a pair of aligned apertures in the sidewalls of one member for movement along a second axis normal to the first axis. The sidewalls of the other member also have a pair of aligned apertures which each define a series of teeth extending in a direction parallel to the first axis of movement. The latch bar is spring biased toward a locking position wherein an abutment formed in the latch is engageable with selected teeth to lock the two members against relative movement. A handle when operated provides force opposing the spring bias and disengages the latch bar from the teeth to permit the members to be moved with respect to one another.

The latch bar extends away from a surface of one of the sidewalls and has a longitudinal notch near its free and defining a short lateral finger. A flat retainer element has an opening receiving the lateral finger, and a body portion disposed in the notch. A cylindrical spring wrapped around the latch and the body portion of the retainer acts against the sidewall surface and reacts against the retainer element to bias the latch away from the sidewall toward its normal locking position.

CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of my copending application filed Feb. 9, 1967 for Adjustable Vehicle Seat Mounting, Ser. No. 614,863.

BACKGROUND OF THE INVENTION (1) Field of the invention This invention relates to latch mechanisms and more particularly to a latch arrangement for interlocking a pair of members against relative movement and including a spring-biased latch bar releasably supported on one of the members for movement along its longitudinal axis between locking and release positions.

(2) Description of the prior art The present invention relates to that class of mechanisms in which a pair of members movable relative to one another, usually in a plane or along an axis are interconnected by a latch bar supported for movement along an axis. Normally, the latch bar has abutments which engage suitable abutments provided in the members in a first axial position and disengage the abutments of at least one of the members in a second axial position. These operative positions will be referred to as a latching position and an unlatching position.

Conventionally, the latch bar is biased toward the latching position by a spring. Suitable stop means limit the axial movement of the latch bar in the direction of spring bias. The spring is arranged around the latch bar with one end acting against one of the sidewalls and its opposite end reacting against a retainer cap which is permanently affixed to the latch by staking or like means.

This arrangement for assembling a latch mechanism of this type presents a serious drawback in that it is a difficult assembly operation to affix the retainer cap to the latch bar in this permanent arrangement. Secondly, where the retainer cap is permanently afiixed to the latch bar, the disassembly of the latch bar mechanism and its associated parts is very difficult and usually requires the permanent deformation of some of the parts such as the retainer cap by the repairman.

It is the purpose of the present invention to obviate the aforementioned problem by providing a mounting arrangement for a latch bar which permits easy assembly, disassembly and reliable operation under the severest of operating conditions.

SUMMARY The preferred embodiment of the present invention is described with reference to a slide device useful in supporting a seat unit for movement between fore and aft positions with respect to a vehicle. However, it is to be understood that the invention is equally applicable to a broad variety of latch mechanisms wherein a spring-biased latch bar is employed for interconnecting members having longitudinal movement between a pair of axially spaced positions.

The preferred embodiment of the invention takes the form of a pair of partially nested, channel-shaped members. The outer channel member is supported for longitudinal movement with respect to the inner channel member. The sidewalls of the outer channel member have a pair of axially aligned apertures. The sidewalls of the inner channel member define a series of teeth extending in a direction parallel to the relative movement of the two members and registering in all positions With the apertures in the outer member.

An elongated latch bar is supported for longitudinal slidable movement in the apertures of the outer channel member and has notches and abutments arranged so that in the latching position the abutments engage a selected pair of teeth in the inner channel member and in the unlatching position the notches register with the teeth to permit the outer channel member to move relative to the inner channel member.

The latch bar also has a shoulder that comes into abutment with the sidewall of the outer channel member to limit the travel of the latch bar in latching position. The end of the latch bar extends away from the sidewall of the outer channel member and has an elongated notch formed in its edge adjacent the end to form a laterally directed finger portion. A flat retainer element is apertured for loose fitting engagement with the finger portion and with the body of the retainer element disposed in the elongated notch.

A coil spring member is retained around the latch with one end acting against the sidewall of the channel member and its outer end acting against a pair of lateral shoulders of the retainer element. The coil spring has an inner diameter such that it is closely wrapped around the latch and that portion of the retainer element disposed in the elongated notch. The spring acts against the retainer element to bias the latch toward the latching position. A force in opposition to the bias of the spring moves the latch toward an unlatched position.

The latch bar is assembled by engaging the bar in th apertures of the channels, inserting the spring around the extending end of the latch and compressing it so that the finger portion and notch are exposed. The retainer element is then inserted on the finger portion such that its body portion lies within the notch. The spring is then released to engage the lateral shoulders of the retainer element. The latch assembly can be quickly disassembled by reversing the aforementioned procedures i.e. by compressing the spring to free the retainer element for disengagement from the finger portion.

It is therefore an object of the present invention to provide a means for releasably attaching a spring-biased elongated member for reciprocal movement with respect to an apertured supporting member by providing a lateral finger section at the end of the elongated member, a retainer element mounted on the finger and a coil spring wrapped around the elongated member to react between the supporting member and the retainer element, the retainer element and the coil spring mutually retaining one another in position.

It is another object of the present invention to provide an improved latch bar mounting for interconnecting a pair of relatively movable members, stop means for limiting axial movement of the latch bar and a retainer and spring arrangement associated with the latch bar for releasably retaining the latch bar in a spring-biased position.

Still further objects and advantages of the present invention will readily occur to one skilled in the art to which the invention pertains upon reference to the following detailed description.

DESCRIPTION OF THE DRAWINGS The description refers to the accompanying drawings in which like reference characters refer to like parts throughout the several views and in which:

FIG. 1 is a side elevational view of a seat slide assembly having a latch arrangement illustrating the preferred embodiment of the present invention;

FIG. 2 is an enlarged transverse sectional view illustrating the preferred latch bar in the latching position;

FIG. 3 is a view taken along the lines 33 of FIG. 2, and

FIG. 4 is a view similar to FIG. 2 but with a latch bar in the unlatching position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Now referring to the drawings, the invention is described with reference to a slide assembly arranged to support a seat unit 12 for movement relative to the floor 14 of a vehicle.

The slide assembly 10 comprises a forward support member 16 and a rearward support member 18 spaced apart from one another and fixedly connected to the floor 14.

As can be seen in FIGS. 2 and 4, the rear support 18 has a generally channel shaped configuration including a pair of spaced parallel sidewalls 20. A conventional elongated slide device 22 is attached to the upper portions of the forward support 16 and the rearward support 18. The slide device has a lower slide element 24 and an upper slide element 26 with their flanges interengaged through ball bearing elements 28 to absorb lateral forces transmitted through the slide device. A pair of roller bearings 30 (only one of which is shown) are arranged in a weight transfer relationship between the upper slide element 26 and the lower slide device slide element 24. It is to be understood that the lower slide element 24 is fixed to the forward support 16 and the rear support 18 so that the upper slide element 26 is longitudinally movable with respect to the lower slide element 24.

A channel shaped support member 32 having downwardly depending sidewalls 34 is fixed to the upper slide element 26. The support 32 carries a bracket 36 which provides means for attaching the seating unit 12. Thus, it is to be understood that the slide device 22 provides a. means for permitting relative movement between the upper movable support member 32 and the lower fixed support member 18. One sidewall 34 of the support 32 has an aperture 38, and its other sidewall has an aperture 40, aligned with aperture 38. The sidewalls of the lower support are formed with racks 42 that extend in the direction of relative motion of the support 32 with respect to the lower support 18. The racks 42 each comprise a series of upwardly directed teeth 44 and connecting slots. Each pair of corresponding teeth 44 is associated with a different relative position of the seat unit 12 with respect to the floor 14. The racks 42 are arranged such that they register in all positions with the

apertures

38 and 40 in the sidewalls 34.

An elongated latch bar 46 is disposed in the

apertures

38 and 40 and supported therein for longitudinal slidable movement. The latch bar 46 includes a body portion 48 having a cross section closely corresponding to the configuration of the aperture 38 and a narrowed end section 50 having a cross section corresponding to the aperture 40.

The narrowed end portion 50 and the body portion 48 defines a shoulder section 52. As can best be seen in FIGS. 2 and 4, the latch bar 46 is therefore movable along an axis defined by the

apertures

38 and 40, its movement toward the left limited by the shoulder 52 coming into abutment with the inner surface of the sidewall 34. This abutting position will be referred to as the latching position.

A notch 54 is formed along the lower edge of the latch bar 46 and arranged such that when the latch bar 46 is moved toward the right a sutficient distance for the narrowed end 50 to register with the left most sidewall 20 of the lower support member 18, the notch 54 registers with the right most sidewall 20. This position is referred to as the unlatched position. It can be seen therefore that in the latching position, the body portion 48 of the latch is engageable between a selected pair of teeth 44 of the racks 42 to lock the upper support member 32 against longitudinal movement with respect to lower support member 18. In the unlatched position, the body portion of the latch clears the teeth 44 to permit relative movement between the upper support member 32 and the lower support member 18.

A notch 56 is formed adjacent the free end of the narrowed end or elongated finger 50 to form an upwardly directed finger portion 58. A fiat retainer element 60 having an aperture 62 and a body portion 64 is arranged such that the aperture 62 is received by the lateral finger 58 and the body portion 64 is disposed between the sidewalls of the notch 56. The body portion 64 has a length preferably slightly less than the length of the notch 56 and a narrowed width to form a pair of lateral shoulders 66. The shoulders 66 are formed such that when the retainer element 60 is engaged with the finger portion 58 the shoulders 66 are near the outer sidewall of the notch 56.

A pair of legs 68 extend from the body portion of the retainer element 60 and closely straddle the sides of the narrowed end 50 of the latch bar. The legs 68 limit sidewise movement of the retainer element 60 when it is engaged with the finger portion 58.

A cylindrical spring member 70 is retained between the retainer element 60 and the sidewall 34. The spring 70 has an inner diameter permitting it to be readily slipped on the narrowed end 50 of the latch bar while closely embracing the latch bar in its retained position. The inner end of the spring 70 acts against the sidewall 34 and its outer end reacts against the shoulder 66 of the retainer element. The spring 70 thereby biases the latch bar 48 toward the latch position.

It can be seen that by this novel arrangement, the spring 70 and the retainer element 60 are mutually and releasably engageable. The retainer element 60 can be easily disengaged from the finger 58 by pressing the spring 70 toward the sidewall while holding the latch in place, however, when the spring is acting against the shoulder 66, the retainer element is captured between the spring 70 and the notch 56. This arrangement permits the latch bar to be quickly assembled or disassembled. However, the interengaging relationship of the spring 70 and the retainer element 60 insure that the latch cannot be inadvertently or accidentally disconnected from the support member 32. Thus, the preferred latch mechanism has all the advantages of reliability of conventional fixed retainer element arrangements with the added advantage of easy assembly and disassembly.

The retainer element 60 has an aperture 72 providing a means for interconnecting a pair of latch mechanisms arranged in series. Thus, a pair of preferred latch mechanisms can be engaged and disengaged simultaneously.

A handle member 74 pivotally supported by a flange 76 on one of the sidewalls 34 provides a means for imposing a force on the lach bar 48 toward the un atching position and against the bias of the spring 70. Thus, the latch bar 46 can be moved by the handle member 74 toward its unlatched position to permit adjustment of the seat 12 with respect to the floor 14, and then the latch bar 46 released for motion toward its latched position by the spring 70 wherein it moves into abutment with a selected pair of teeth 44 associated with the selected position.

Although I have described but one preferred embodiment of my invention, it is to be understood that various modifications and revisions can be made therein without departing from the spirit of the invention as expressed in the scope of the appended claims.

What is claimed is:

1 A latch mechanism comprising:

(a) a first member having an aperture;

(b) a second member having an aperture, the second member being supported on the first member for motion with respect to the first member along a path in which the apertures of the two members are aligned with one another;

(c) an elongated latch, said latch being disposed in said apertures, having an abutment engageable with a cooperating abutment of one of said members, and being movable along its longitudinal axis between a latching position wherein said abutments are engaged to prevent the second member from being moved along said path with respect to the first member; and an unlocking position wherein the latch is inoperable to prevent relative movement between said first and second members;

((1) stop means limiting movement of said latch in a first direction along its longitudinal axis;

(e) means biasing said latch in said first direction, said biasing means comprising;

(1) said latch having a notch formed along its longitudinal edge, to define a lateral finger adjacent one end of the latch;

(2) a retainer element, having an aperture releasably receiving said lateral finger; and

(3) a cylindrical helical spring enclosing a portion of the latch and a portion of the retainer element to prevent separation of said retainer element with respect to the lateral finger, said spring having a first end acting against one of said members, and its second, opposite end reacting against said retainer element to bias the latch in its first direction.

2. A latch mechanism as defined in claim 1, wherein said latch is movable along its longitudinal axis in response to a force applied to said latch in opposition to the bias of said spring.

3. A latch mechanism as defined in claim 1, wherein the aperture of said first member is provided with a series of abutments extending parallel to said path of motion and said latch is longitudinally slidably disposed in the aperture of said second member so that the abutment of said latch member is engageable with selected abutments of said series of abutments of said first member to lock the second member against motion with respect to said first member in a selected relative position.

4. A latch mechanism as defined in claim 1, wherein said notch includes a pair of longitudinally spaced sidewalls connected by a base portion, and said spring biases said retainer element against one of said sidewalls and away from said members.

5. A latch mechanism as defined in claim 4, wherein said retainer element has a pair of lateral shoulders, having a width at least as great as the outer diameter of said spring to provide an abutment for said spring when said retainer element is engaged with said lateral finger.

6. A latch mechanism as defined in claim 5, wherein said retainer element has a body portion, disposed between the sidewalls of said notch and substantially enclosed by said spring.

7. A latch mechanism as defined in claim 6, wherein said body portion and said notch cooperate to prevent said retainer element from being disengaged from said lateral finger while said spring is acting against the shoulders of said retainer element to bias the latch in its first direction.

8. A latch mechanism as defined in claim 6, wherein said body portion and said notch cooperate to prevent said retainer element from being disengaged from said lateral finger without compressing said spring away from the shoulders of said retainer element and toward said members.

9. A latch mechanism as defined in claim 8, wherein said retainer element has a pair of leg sections closely straddling opposite sides of said latch and enclosed by the spring.

10. A latch mechanism as defined in claim 9, wherein said biasing means normally urges said latch toward said latching position.

11. The combination, comprising:

(a) a first member having an aperture,

(b) a second member having an elongated finger with a free end extending through said aperture, the second member being supported such that the free end of said finger is movable toward and away with respect to the first member along the longitudinal axis of the finger;

(c) stop means limiting displacement of the free end of said finger away from the first member;

((1) a laterally directed portion on the free end of the (e) a retainer element apertured for releasably receiving said lateral portion; and

(f) a cylindrical helical spring arranged around said finger with one end of said spring abutting against said first member, and its opposite end abutting against said retainer element such that the spring normally biases the free end of the finger away from the first member.

12. The invention as defined in claim 11, wherein said finger has a notch formed along its longitudinal edge, said notch terminating adjacent the end of said finger to define said lateral portion.

13. The invention as defined in claim 12, wherein said finger has a body portion having a uniform cross section disposed for longitudinal slidable movement through said aperture.

14. The invention as defined in claim 12, wherein said finger is movable along said axis in response to a force applied to said finger in opposition to the bias of said spring.

15. The invention as defined in claim 12, wherein said notch includes a pair of spaced sidewalls connected by a base portion, said retainer element having a body portion disposed between the sidewalls of said notch and enclosed by said spring.

16. The invention as defined in claim 14, wherein said retainer element is formed of a flat section having a pair of lateral shoulders, said lateral shoulders having a width accommodating said spring so that said shoulders provide an abutment for said spring when said retainer element is mounted on said lateral portion.

17. The invention as defined in claim 14, wherein said body portion and said notch cooperate to prevent said retainer element from being disengaged from said lateral portion while said spring is acting against the shoulders of said retainer element.

18. The invention as defined in claim 17, wherein said spring has an inner diameter such that said retainer element cannot be disengaged from said lateral portion without compressing one end of the spring toward its other end.

19. The invention as defined in claim 18, wherein said retainer element has a pair of leg sections closely straddling opposite sides of said finger and enclosed by the spring.

20. In a seat adjusting mechanism for supporting a seat in a selected adjusted position with respect to a floor panel, the combination comprising:

(a) a first support suited for connection to the floor panel;

(b) a second support suited for connection to the seat, and mounted on the first support for motion along a predetermined path with respect to the first support;

(c) an elongated latch bar mounted on one of the supports for motion along its longitudinal axis in either a first direction, or in the opposite second direction between a locking position in which the latch bar is operable to prevent the second support from being moved with respect to the first support along said path, and an unlocked position in which the latch bar is inoperable to prevent'the second support from being moved with respect to the first support;

((1) means on the latch bar engageable with one of the support for limiting motion of the latch bar in its first direction;

(e) a retainer mounted on the latch bar in a retaining position in which it is locked against motion with respect to the latch bar in directions along the longitudinal axis of the latch bar, the retainer being formed such that it is separable from its retaining position on the latch bar only by a motion in a lateral direction with respect to the longitudinal axis of the latch bar; and

(f) a spring mounted between one of the supports and the retainer to bias the latch bar in its first direction, the spring being formed such that it encloses a portion of the retainer to prevent the retainer from being moved a sufficient distance in a lateral direction with respect to the latch bar to be separated from the latch bar.

21. The combination as defined in claim 20, in which the spring is formed in the shape of a cylinder with one of its ends being movable toward its other end a suflicient distance to allow the retainer freedom formotion toward its lateral direction of separation from the latch bar.

22. The combination as defined in claim 20, in which the latch bar has a notch formed along its longitudinal edge for receiving the retainer, and the retainer is engaged with the spring such that the spring biases the retainer toward one end of the notch and encloses the portion of the retainer in the notch.

References Cited UNITED STATES PATENTS 3,052,443 9/ 1962 Lagstrom 248-430 1,062,593 5/1913 Isidor 16142 2,088,784 8/1937 Galamb et a1. 248394 2,190,972 2/1940 Boldt 74537 2,213,232 9/1940 Thompson 20050.3

FRED C. MATTERN, JR., Primary Examiner.

CAROLYN F. GREEN, Assistant Examiner US. Cl. X.R.

( o-1050 UNlTED STA'IES PA'll'fiNT OFFICE CERTIFICATE OF .CORRhUlION patent 3,491, 979 Dated January 27 1970 Inventor(s) H. WONELL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

C01. 1, line 32, "and" should be --end-.

SIGNED AND SEALED JUN 2 31970 6 5 Attest:

Edward M. Fletcher, In, WEE-Ill! E. BGHUYIER, JR. An i offi flomissione r or Patents