US2750219A - Latch mechanism - Google Patents

Description

June 12, 1956 H. A. BLEAM LATCH MECHANISM 4 Sheets-Sheet 1 Filed July 1l, 1952 2 2 m@ a y J mi N 1. "0T A f f ,m W a w June 12, 1956 H. A. BLEAM 2,750,219

LATCH MECHANISM Filed July ll, 1952 4 Sheets-Sheet. 2

INVENTOR.

June 12, 1956 H. A. BLEAM LATCH MECHANISM 4 Sheets-Sheet, 3

Filed July l1I 1952 June 12, 1956 H. A. BLEAM LATCH MECHANISM 4 Sheets-Sheet. 4

Filed July 11, 1952 INVENTOR. eczzfz n 2,750,219 Patented June 12', 1956 LATCH MECHANISM Howard A.. Blearn, Chicago, Ill., assigner to Admiral Corporation, Chicago, lli., a corporation of Delaware Application July 11, 1952, Serial No. 298,265

7 Claims. (ci. z -19s) This invention relates to latch mechanism for releasably retalning two members together, there being relative movement between the members when the latch mechanism is unlatched. More specifically, the invention comprehends latch mechanism for a door to close an opening in a casing, the operation of latching the door to retain it in closed position and/or unlatching it for its movement with respect to the opening being adapted to be carried out without the aid of conventional handles either 011 the door itself or in connection with the latch mechanism.

Although latch mechanisms of the foregoing description are known to the prior art, their structures are comparatively intricate and consequently expensive of manufacture and subject to maladjustrnent.

Owing to the present invention latch mechanism of the foregoing description has been provided which is of simplified construction and which is consequently less expensive of manufacture and less subject to maladjustment. By the present invention a latch mechanism is provided in which not only is less metal required for its construction but by'its use metal door knobs, pulls or handles are dispensed with. Other advantages will be apparent from the specification which is descriptive of the accompanying drawings, in which:

Fig. l is a fragmentary sectional view of a door and casing with a latch mechanism about to be engaged taken on line 1--1 of Fig. 2;

Fig. 2 is a fragmentary sectional view at right angles to Fig. l;

Fig. 3 is a view corresponding to Fig. l, with the latch mechanism in engaged position;

Fig. 4 is a View also corresponding to Fig. l, the keeper being shown in a still different position;

Fig. 5 is a perspective view of a second embodiment of the invention;

Fig. 6 is an elevational View of the keeper unit of the second embodiment, parts being broken away to reveal other parts;

Fig. 7 is a view corresponding to Fig. 6, the latch mechanism being in a different position;

Fig. S is an elevational View of a third embodiment of the invention, in unlatched position;

Fig. 9 is a view corresponding to Fig. 8, the parts being shown in latched position;

Fig. l is a perspective view of the slider housing;

Fig. l1 is a perspective View of the slider;

Fig. l2 is a vertical section on line 12-12 of Fig. 9;

Fig. 13 is a fragmentary sectional view taken on line 13-13 of Fig. 1'6 and showing a fourth embodiment of the invention;

Fig. 14 is a view corresponding to Fig. 13 showing the keeper in a'different position;

Fig. l is a view corresponding to Fig. 13 showing the keeper in a still different position; and

Fig. 16 is a fragmentary sectional View taken on line 16-16 of Fig. 13.

` The mechanism shown in Figs. -1 and 2 includes a frame, housing or casing 2 defining an opening 3 which may be in a cabinet adapted to be closedby a door 4 movably anchored to the casing in any convenient manner such as by one or more hinges 6. The door is therefore movable freely in a predetermined course relative to the opening 3 and may be limited in its inward movement'by a stop portion or surface 7 on the casing. For a purpose later to be described, the door is biased, to a limited extent, away from the stop surface 7, by suitable resilient means carried by the door and adapted to engagethe surface 7 or carried by the casing and adapted to engage the door as it is moved into adjacent relationship to the stop surface. In the embodiment referred to, the resilient means takes the form of a leaf spring 8, one end of which is anchored on the inner side of the door Vin a recess 9 out of which the spring slopes outward and terminates in a free end 11 adapted to engage the surface 7 and thereby to be deected into the recess when the door is brought into engagement with `the stop surface.

The door 4 is adapted to be releasably retainedV Vin closed relationship to the opening 3 by novel latch mechanism. It comprises a pin, stud or follower 12 on the edge of the door 4, opposite the hinged edge, and a keeper 13 pivoted at 14 to the casing 2. In order that the keeper 13 may offer no obstruction to movement of the door 4, but may cooperate with the pin 12, the keeper is positioned within a recess 16 in the casing at the edge of opening 3. The mechanism by which the keeper is caused to move about pivot 14 will now be described.

Preferably struck from sheet metal, the keeper 13 is further defined largely by curved surfaces the function and nature of which will later be indicated. Although the thickness of the stock for the keeper is not critical, it may be from 1/16 to 1,4; of an inch in thickness. Suitable keepers were made from sheet brass approximately V32 of an inch in thickness. A part of the edge of keeper 13 is dened by a cam surface 17 which spirals outward about the pivot 14 from a stop surface 18 at the inner end of said cam surface. The keeper 13 also includes a hook portion or arm 19, generally arcuate in extension about the pivot 14, and which terminates in a free end 21. Arm 19 is spaced from the cam 17 by a channel 22 extending from a throat 23, between the free end 21 and cam 17, to the stop surface 18. Although the throat 23 is of width only slightly greater than the diameter of pin 12, the width of the channel broadens from the throat 23 into a socket 24 on the inner side of the arm 19, the purpose of the socket being later to be indicated. From the socket 24 the width of the channel 22 gradually diminishes to the stop surface 18.

In order that there may be cooperation between the follower 12 and keeper 13, said follower is so positioned, on the door, that it is adapted to be carried through a plane, in which the vertical axis of the keeper 13 is disposed and, through a plane slightly higher than the plane of the keepers horizontal axis, depending on the curvature of cam 17. Following engagement of cam 17 by the pin 12, the force of the latter is followed by clockwise rotation of the keeper 13, due, of course, to a tendency of said cam to ride over the pin. The stop surface 18 is thus carried into engagement with or into the proximity of the follower depending on the force with which the door is closed. When the force necessary for closing the door is spent or neutralized by the reactional force of spring 8, said spring urges the door outward. Whether the follower 12 then latchably engages the arm 19 or not depends on the violence with which the door was closed and the rapidity with which it consequently rebounds by the force of the spring.

To understand the manner in which the latching is effected, it should be understood that the keeper 13 is rotated to its Fig. 1 position by gravity at a predetermined rate when swung away from this position and released. The rate at which the pin 12 may move to the left, however (Fig. 1), is governed by the violence with which it is moved manually inward. It therefore follows that with suflicient rebound from its innermost position (Fig. 3), the follower may intercept the arm 19 before gravity has had time to move it below the course through which the follower is carried in moving outward. Consequently, the arm 19 engages the pin 12 and thus operatively resists movement of the door outward. At this point, it is noteworthy that there is adequate friction between arm 19 and pin 12, augmented by the spring, to operatively resist the urge of gravity to rotate keeper 13 from its Fig. 3 to its Fig. 1 position. Thereafter, the spring releasably retains the follower 12 in engagement with arm 19; that is, in latched engagement with said arm. Moving the door closed and gradually allowing it to be opened by the spring at a rate slow enough for the end 21 to be lowered below the plane through which follower 12 is adapted to be carried is not, of course, accompanied by any latching engagement of the follower by the keeper. Thus it follows that to unlatch the follower 12 from keeper 13 it is only necessary to depress the door against the spring 8 adequately to enable gravity to rotate the keeper counterclockwise to its Fig. 1 position.

The second embodiment of the invention (Figs. 5, 6 and 7) includes a cam or keeper 26 in combination with a housing 27 therefor, the cam being similar to cam 13 of the embodiment previously described. The housing is preferably formed of sheet metal and includes a rectangular end portion 28 from opposite edges of which uniformly spaced-apart side walls 29 and 31 extend. The wall 29 is flanged perpendicularly toitself at 32 and extends to the wall 31. The wall 31, on the other hand, also bears a flange 33, perpendicular thereto, by which the housing is adapted to be anchored to a cabinet or door. The flange has holes, one of which is indicated at 34, for reception of anchor screws or bolts. The keeper 26 is, of course, rotatably supported and this is on a shaft 36, the ends of which are fixed to the walls 29 and 31. The shaft 36 is so disposed with respect to a clearance slot 37, in the wall 29, and companion clearance slot 38, in the wall 31, that when there is movement between a follower or pin 39 and the keeper 26 a cam surface 41 on the keeper may be engaged by the follower to rotate the keeper as previously indicated.

The follower 39 is supported by a bracket 42 which is also preferably struck from sheet metal having a flange 43 which is slotted at 44 in which the pin 39 is received and in which said pin is adjustably clamped by a nut 46 on either side of the flange 43. Additionally, the follower 39 may be adjusted longitudinally thereof, both by the aid of the nuts 46 and/ or a pair of slots 47 through which screws are adapted to pass into the support for bracket 42.

Within the housing 27 is provided resilient means to urge the follower away from the keeper 26. Said means may comprise a spring 48, coiled about a rod 49 the ends of which are supported by walls 29 and 31 of the housing 27. The spring 48 includes an arm 51, normally engaged by the wall 32, and an arm 52 in engagement with the wall 28, to resist uncoiling of the spring (Fig. 6). As the follower 39 is carried toward the keeper, said follower first engages the arm 51 of spring 48 which is additionally deflected (Fig. 7) and performs the function of maintaining latched engagement between an arm 53, of the keeper 26 and the follower 39. Latching and unlatching of the mechanism is performed in the same manner as has already been described in connection with the embodiment first referred to.

The third embodiment of the invention, illustrated in Figs. 8 to l2 inclusive, comprises a keeper unit 54 and a follower unit 56. The follower unit comprises a support member 57 (Fig. 10) which is generally rectangular in formation and preferably struck from sheet metal. [t has flanges 58 struck outwardly from either side thereof, both of which converge and extend away from the mem- .4 ber 57. The purpose of the arms 58 is to embrace (Fig. l2) a pair of diverging arms 59 extending from opposed edges of a striker member 61, also of generally rectangular conformation and preferably formed from sheet metal. In the space between the arms 59 is supported a compression spring 62 one end of which engages a lug 63, struck vertically from the surface of the striker member 61, while the remaining end of said spring is adapted to engage another lug 64 on the central portion S7 of the support member. Normally, as when the follower unit 56 is out of cooperative association with keeper unit 54 the force of spring 62 biases the lug 63 into engagement with a pin or follower member 66 fixed to the central portion 57 toward the end thereof.

The follower is adapted to be carried into a slot 67 in the keeper unit 54, o-r the slot carried over the follower depending on whether the keeper unit or follower unit is mounted on the door. Regardless of which mounting is adopted the spring 62 is compressed as the follower enters the slot 67, since lug 63 is wider than said slot. In the course of this operation pin 66 engages a cam surface 68 on a keeper 69, identical in structure to the keeper 13, and journaled on a shaft 71 which is in fixed relationship to a keeper housing 72.

The operation of latching and uulatching the units 54 and 56 to each other is an previously described, the cam 69 being adapted to be rocked against the force of gravity from its normal position (Fig. 8) to and beyond its Fig. 9 position to which it is returned by its own weight and wherein an arm 73 retains the follower 66 against the force of spring 62. Once the follower 66 is released from the arm 73, the spring 62 moves the keeper unit 54 in a direction away from the follower unit.

In the fourth embodiment of the invention, shown in Figs. 13 to 16 inclusive, a keeper unit 75 includes a keeper 76 which is adapted to be maintained in either of two positions by spring pressure. In order that this may be carried out a frame 77 is provided which is formed from sheet metal. The frame 77 includes a rectangular base portion 78 from one side of which a flange portion 79 extends to provide support for an arm 81 integral with the flange portion and uniformly spaced from the base portion 78 to afford accommodation therebetween for the keeper 76. A shaft 82 between the arm 81 and base portion 78 provides bearing support for the keeper 76. Since spring pressure, later to be described, is employed to releasably station the keeper 76 in one of its positions, it is unnecessary that the center of gravity of the keeper be eccentric to its pivotal support as in the previously described illustrations of the invention. Consequently, the keeper unit 75 is adapted to be mounted in any operative position on either a casing 83 or a door 84.

In order that the keeper 76 may be moved to either of the positions referred to, the arm 81 carries a spring 86. It is generally arcuate in formation and may be of some resilient material such as steel music wire. One end of the spring 86 passes through a lug 87, at the free end of arm 81, thence through a second lug 88, on said arm to which the spring end is clamped by a set screw 89. The other end of the spring 86 passes freely through one of a plurality of holes 91 at the edge of the keeper 76, the particular hole used being best determined by test. While so confined, the spring 86 constantly exerts a downward force on the keeper tending to urge the keeper in a counterclockwise direction (Fig. 13) thereby providing one extreme keeper position. When the keeper 76 has been rotated clockwise by cooperation of a cam 92 thereon with a follower 93, on the door, the clockwise motion of the cam is arrested in proximity to another eXtreme position by the follower (Fig. 14). Between its two extreme positions, the keeper passes through an over-thecenter position from either side of which the spring 86 is adapted to bias the keeper toward its nearest extreme position. From the position indicated (Fig. 14) the follower 93 is moved byv a spring 94 (Fig. 16), a counternpart of spring 8 (Fig. l) slightly to the left, which op- 'permitted by a socket 97 on the arm 96. It will now be apparent that moving the door 84 slightly in an inward direction so that follower 97 is carried momentarily to the right (Fig. l) frees the keeper for movement counterclockwise by the spring 86 to its Fig. 13 position so that the door is free to be opened.

Although my invention has been described in four ernbodiments thereof, I am aware that numerous and extensive departures may be made from the structures disclosed without departing from the spirit or scope of the invention.

I claim:V

1. A door latch having a follower for the door and a latch for the door opening disposed opposite to the follower, said latch comprising a plate pivotally supported and freely revolvable about a fixed axis, a curved tongue on said plate providing a spiral-shaped channel between `said tongue and said plate having an open throat at one end in spacedv relation to said' axis and extending spirally inward relative to said axis to a'stop surface formed on the end of said channel opposite to said throat, said tongue being formed with a curved follower engaging surface which is curved about the pivot for the latch, said plate having a gravitational center spaced from said axis being operable to normally present said follower engaging surface to said follower, the radius of said follower engaging surface relative to said axis being greatest at a point spaced from the end of the tongue and less on either side thereof, said tongue arranged to move to a follower engagmg position upon rotation of said plate and said curved follower surface arranged to engage and retain said f ollower upon movement of said plate to follower engagmg position.

2. A door latch having a follower for the door and a latch for the door opening disposed on the casing opposite to the follower, said latch comprising a plate plvotally supported and freely revolvable about a fixed axls, a curved tongue on said plate providing a spiralshaped channel between said tongue and said plate havmg an open throat at one end in spaced relation to said axls and extending spirally inward relative to said axis to a stop surface formed on the end of said channel opposite to said throat, said tongue being formed with a curved follower engaging surface which is curved about the pivot for the latch, said plate having a gravitational center spaced from said axis being operable to normally present said follower engaging surface to said follower, the radius of said follower engaging surface relative to said axis being greatest at a point spaced from the end of the tongue and less on either side thereof, said tongue arranged to move to a follower engaging position upon rotation of said plate and said curved follower surface arranged to engage and retain said follower upon movement of said plate to follower engaging position, and spring means between the door and casing resiliently holding said door toward an open position with said follower seated at the point of greatest radius of said follower engaging surface on said tongue.

3. The combination with a first member movable toward and beyond a latching position relative to a second member, of resilient means associated with one of the members for constantly urging the first member backward through its latching position whenever said rst member has been moved therebeyond, latching mechanism operative when the first member is moved in one manner to latchably couple the members together and capable of being unlatched when said first member is moved n another manner including an adjustable follower on said movable member, a latch unit for the other of said members comprising a casing connected to said other member, a plate pivotally supported to and freely revolvable about a fixed axis on said casing and disposed oppositely to said follower, a curved tongue on said plate providing a spiral-shaped channel between said tongue and said plate having an open throat at one end in spaced relation to said axis and extending spirally inward relative to said axis to a stop surface formed on the end of said channel opposite to said throat, said tongue being formed with a curved follower engaging surface which is curved about the pivotal axis of the plate, said plate having a gravitational center spaced from said axis being operable to normally present said follower engaging surface to said follower, the radius of said follower engaging surface relative to said axis being greatest at a point spaced from the end of the tongue and less on either side thereof, said tongue being in an unlatching position and said follower engaging surface being positioned for engagement with said follower before said members are at their latching position, said follower engaging said follower engaging surface to move said tongue to a follower engaging position when the first member is moved beyond its latching position, movement of the first member back to its latching position quickly enough serving to latchably engage said follower by said tongue before said tongue can be returned to its unlatching position thereby to latchably secure the members in latched relation to each other, said members being unlatched from each other when the first member is moved against the resilient means slowly enough to enable the tongue of said plate to move to its unlatched position.

4. The device as defined in claim 3 and wherein the follower comprises a bracket carried by the movable member and a follower element adjustably coupled to said bracket.

5. A door latch for a door hinged for movement toward and beyond a latching position relative to a closable member defining a door opening comprising a bracket secured to said door, a follower adjustably coupled to the bracket for axial and lateral adjustment relative thereto, said bracket also having anchor slots therein for passage of anchor bolts therethrough and into said door, by which said bracket is adjustably clamped to said door, a casing connected to said closable member disposed opposite to said follower and having spaced-apart walls and a slot in at least one of said walls for entrance of said follower, resilient means supported within said casing and extending past the slot for constantly urging the follower out of the casing to its latching position, a plate pivotally supported between said walls and freely revolvable therebetween, a curved tongue on said plate providing a spiral-shaped channel between said tongue and said plate having an open throat at one end in spaced relation to said axis and extending spirally inward relative to said axis to a stop surface formed on the end of said channel opposite to said throat, said tongue being formed with a curved follower engaging surface which is curved about the pivotal axis for the plate, said plate having a gravitational center spaced from said axis being operable to normally present said follower engaging surface to said follower, the radius of said follower engaging surface relative to said axis being greatest at a point spaced from the end of the tongue and less on either side thereof, said follower upon said door being moved toward said closable member beyond said latching position being carried thereby against the resistance of said resilient means into engagement with said follower engaging surface on said plate and operable to swing said tongue to a latching position, said door being latchably coupled to the closable member when said door is released to move backward before said tongue can be returned to its unlatched position, said door and closable member being unlatched from each other when backward movement of said door is at a rate slower than it can be moved by the resilient means to free said tongue to its unlatchable position.

6. A door latch for a closing member hinged for movement toward and beyond a latching position relative to a closable member comprising a housing fixed to said closing member, a follower on the housing, a springbiased movable striker, guide means on the housing to slidably anchor the striker thereto and confine said striker for movement into greater and less proximity to the follower, a casing in said closable member, said casing being formed with at least one wall having therein a slot extending horizontally from one of its edges and being capable of accommodating the follower, a plate pivotally supported and freely revolvable about a fixed axis on said casing, a curved tongue on said plate providing a spiralshaped channel between said tongue and said plate having an open throat at one end in spaced relation to said axis and extending spirally inward relative to said axis to a stop surface formed on the end of said channel opposite to said throat, said tongue being formed with a curved follower engaging surface which is curved about the fixed axis of said plate, said plate having a gravitational center spaced from said axis being operable to normally present said follower engaging surface to said follower, the radius of said follower engaging surface relative to said axis being greatest at a point spaced from the end of the tongue and less on either side thereof, and said follower engaging surface being normally presented to said follower at the level of said slot, said follower being arranged to extend into the slot and into engagement with the follower engaging surface to swing the tongue upward adequately to confine said follower between said tongue and said follower engaging surface against the resistance of said biased striker.

7. A device as defined in claim 6 and wherein the follower on said door extends laterally from the housing on one end thereof, and resilient means are supported by the housing to provide for biasing the striker into association with the follower.

References Cited in the le of this patent UNITED STATES PATENTS 652,828 Bailey July 3, 1900 837,811 Ebbeson Dec. 4, 1906 1,589,874 Ewing June 22, 1926 1,896,363 Johnson Feb. 7, 1933 2,427,134 Gronbeck Sept. 9, 1947 2,458,751 Voight Jan. 11, 1949 2,548,046 Nottingham Apr. 10, 1951 FOREIGN PATENTS 9,895 Great Britain 1886 16,566 Great Britain 1891 35,364 Denmark Dec. 7, 1925 86,655 Sweden `Tune 23, 1936

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