|Publication number||US3438153 A|
|Publication date||Apr 15, 1969|
|Filing date||Nov 24, 1967|
|Priority date||Nov 24, 1967|
|Publication number||US 3438153 A, US 3438153A, US-A-3438153, US3438153 A, US3438153A|
|Inventors||Philip Di Lemme|
|Original Assignee||Philip Di Lemme|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (5), Referenced by (39), Classifications (7)|
|External Links: USPTO, USPTO Assignment, Espacenet|
P. Dl LEMME April 15, 1969 WINDOW LOCK Sheet Filed Nov. 24, 1967 FIG.2
INVENTOR. PHILIP Di LEMME www M 3. m. Cl
ATTORNEYS April 15, 1969 P. Dl LEMME WINDOW LOCK Filed Nov. 24, 1967 INVENTOR.
PHILIP Di LEMME 6M m Ma. ATTORNEYS United States Patent O US. Cl. 49--451 10 Claims ABSTRACT OF THE DISCLOSURE The application discloses a one-piece stamped sheet metal window latch for sliding windows and the like. The latch is carried in a channel within the window sash, the latch being adjacent to an edge of the sash. The major portion of the latch, which includes a finger hole, rests normally substantially vertically within the channel and is spring biased toward the adjacent sash frame. A portion of the latch adjacent the edge of the sash is notched and bent along the longitudinal axis of the latch through an acute angle with respect to the major latch portion. This bend end of the latch carries a curved or tapered edge which frictionally engages a portion of the sash frame to effectively lock and hold the window sash in an open position to which it may be slidably moved. To close the window sash, the latch is easily retracted from its locking position by finger pressure applied in opposition to the spring bias. During such motion of the sash, the latch cocks within its channel, thus enabling the friction locking edge to slide freely within the sash frame without requiring manual retraction.
Background of the invention The invention is particularly directed to storm windows and screens of the now popular type which are slidably mounted in aluminum frames and are not counterbalanced. It represents an improvement over the window lock construction disclosed in my prior U.S. Patent No. 3,153,264, which issued on Oct. 20, 1964. The crux of the improvement is in the simplified latch construction which eliminates the multiple parts required for all prior art window sash latches, and enables an effective latch to be more economically manufactured by a simple onepiece sheet-metal stamping. The special metal castings and additional parts required to be manufactured and assembled for prior windows are now completely eliminated by the present invention.
rlhe most common prior art window latches for metal sash storm windows and screens, have employed retractable slides carrying pins or other protuberances which are adapted to engage notches, ratchets or discretely spaced socket holes `formed within the vertical grooves of a sash frame. While such structures provide positive locking of the window sash when the latch pin is engaged in a cooperating notch, they have the disadvantage of limiting the number of positions at which the window can be held to the fixed number and spacings of the notches. Furthermore, providing the required notches in the upright members of the sash frame is a tedious and costly manufacturing operation.
Accordingly, it is an object of my present invention to provide an improved latching window sash and frame which is more economical to manufacture than those of the prior art.
It is also an object of the invention to provide such an inexpensive latch which is capable of holding a window securely at any position to which it may be raised, without being limited to predetermined notch positions.
Another object is to provide such a window latching means which allows the window to be raised without "ice `requiring manual retraction of the latching mechanism.
Other objects of the invention will in part be obvious and will in part appear hereinafter.
The invention accordingly comprises an article of manufacture possessing the features, properties, and the relation of elements which will be exemplified in the article hereinafter described, and the scope of the invention will be indicated in the claims.
Brief description of the drawings For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:
FIGURE 1 is a fragmentary front elevational view of the lower portion of the indoor side of a storm window incorporating the invention;
FIGURE 2 is an enlarged view of one of the window latches shown in FIGURE 1, with a portion of the window sash cut away;
FIGURE 3 is a perspective view of the one-piece sliding latch shown in FIGURE 2; and FIGURE 4 is an enlarged sectional view of the lower horizontal window sash channel taken a-long the line 4 4 of FIGURE 1.
Description of the preferred embodiment The present latch construction is suitable for use with windows, screens and other such closures of both the vertically and horizontally sliding variety. These closures may have frames made of metal, wood or any other suitably rigid material. However, for purposes of illustration, we will describe the latch in connection with a vertically sliding window whose frames are made of metal. This is the construction normally used in conventional combination storm window and screen units. Also, the illustrated window employs two of my latches. But it should be understood that in some applications (e.g. a horizontally sliding window), one may suffice.
Referring now in greater detail to FIGURE 1 of the drawings, sash frame 18 includes a pair of parallel upright channels 11-11 which contain a vertically slidable Window sash 12. A horizontal bottom channel 14 of window sash 12 contains a pair of horizontally slidable latches 15 and 15a, the construction and operation of which is the subject of the invention.
Referring now in greater detail to FIGURES 2 and 3 of the drawings, the configuration and operation of latch 15 in bottom sash channel 14 will be described. As shown in the perspective view of FIGURE 3, latch 15 is formed of a one-piece sheet metal stamping having a major dished portion 16 of generally rectangular configuration. Portion 16 has a fiat front wall 16a and top and bottom inclined walls 16]; and 16C, bottom wall 16e being somewhat wider than wall 16b. Also, portion 16 has a top edge 17 and a narrower bottom edge 18 which are parallel and which guide latch 15 for horizontal sliding motion within channel 14. As seen in FIGURE 4, the aforesaid shaping of portion 16 results in edge 18 being offset back from edge 17 for reasons to be described later. A protruding nib 19 (FIGURE 3) engages one end of a coil spring 2l) (FIGURE 2) which is held in compression within channel 14 by a lug 21 which extends inwardly from a vertical side wall of channel 14. Spring 20 urges latch 15 to slide toward the left, as viewed in FIGURE 2.
In stamping latch 15, a pair of notches 22 and 24 are formed as shown in FIGURES 2 and 3, while a curved and tapered end portion 25 is formed on the left hand extremity of latch 15, as also shown in FIGURES 2 and 3. Between notches 22 and 24, the left hand upper portion 26 of latch 15, including the tapered extremity 25,
is bent along a horizontal axis 27 into an inclined plane forming an angle of approximately sixty-live degrees with edges 17 and 18 of major latch portion 16. Because of notch 24, the leading edge 2S of tapered portion 25 now extends forward of the plane of front wall 16a of the major portion 16, as viewed in FIGURES 2 and 3. A generally rectangular finger opening 29 is formed in wall 16a of latch 15 to facilitate application of finger pressure to move the latch from left to right against the force of spring 20.
As shown in FIGURE 2, a portion of the latch extremity 25 extends into the vertical channel 11 and a portion of leading edge 28 frictionally engages the inner corner edge 31a of a vertical channel upright 31 to hold the window sash 12 in any position to which it is raised. The right hand latch 15a, shown in FIGURE 1, operates in the same manner and the two latches cooperate to hold the sash 12 securely. To release latch 15 and lower sash 12, it is only necessary to apply light finger pressure to the right hand edge 36 of opening 29 whereby latch 15 may be slid a fraction of an inch to the right against the force of spring 2t?, thereby disengaging leading edge 28 from its frictional engagement with edge 31a of upright 31.
To effectively lock window sash 12 in its closed position, a notch 32 is formed in vertical channel upright 31, as shown in FIGURE 2, and the leading edge portion 28 of latch 15 is forced into notch 32 by spring 20, thereby preventing raising of sash 12 from its closed position, except through release of latch 15 via access to the inside of the window.
As indicated generally hereinabove, latch 15 ts loosely within horizontal sash channel 14 and, when not frictionally engaged with channel upright 31, is free for limited rocking motion about a horizontal axis within channel 14. The manner in which latch 15 is thus loosely and rockingly held within channel 14 is shown by the enlarged cross sectional view of FIGURE 4, taken along the line 4 4 of FIGURE l.
Referring now in greater detail to FIGURE 4, the horizontal sash channel indicated generally at 14 comprises an upper channel portion 34 of width W1, connecting with a central channel portion 35, of width W2 substantially greater than W1, which is open on the inside (to the left as shown in FIGURE 4), which in turn connects with a substantially smaller bottom channel portion 36 of Width W3 which is substantially less than W1 or W2.
The leading edge 28 of latch 15 is normally biased by spring 2t) (FIGURE 2) into frictional engagement with vertical channel edge 31a. The action of spring 20 coupled with the wedging of edge 28 against channel edge 31a tends to bias latch 15 away from upright 31 (i.e. to the right in FIGURE 4) so that an edge 26a of latch portion 26 engages wall 35a of channel portion 35 near the top of that channel portion. The oppositely directed forces at edges 28 and 26a complete a force couple which tends to tilt or cock the entire latch 15 clockwise so that it assumes the substantially vertical position shown by solid lines in FIGURE 4. In this position, the upper edge 17 of major portion 16 extends up almost to the top of channel portion 34, while its lower edge 18 is displaced upward from the bottom channel portion 36.
The combined widths of latch portions 25 and 26 and their angle of tilt relative to the vertical are related to the width W1 of channel portion 35 so that edge 28 is wedged into nonslip engagement with edge 31a. In this, the aforesaid angle is fairly critical. If it is too small, the force component tending to wedge latch portion 25 against channel upright 31 may be insuicient to obtain locking action. On the other hand, if the angle is too great, the sharp edge of portion 25 is not presented to edge 31a and the two may not as readily frictionally engage. Once they do, however, in extreme cases the latch may jam in the locked position. In practice, we have found that when portions 25 and 26 are bent at an angle of about sixty-ve degrees relative to edges 17 and 18, portions 25 and 26 become oriented properly within sash 14 to satisfactorily lock the window. The latch also operates somewhat less satisfactorily using any angle between 35-70 degrees, but still performs its locking function.
It is seen from the foregoing that the present lock yields a locking action which accommodates itself to the weight of the particular sash. More particularly, the heavier the sash, the greater are the forces developed at edges 28 and 26a of latch portion 26 tending to cock the latch into tight wedging engagement between channel edge 31a and wall 35a of channel portion 35. Consequently, latch 15 will not disengage even when used on heavy prime windows having wooden frames. In this application, however, it is desirable to still form edge 31a of metal to maximize the useful life of the window unit.
Desirably, end 26a of latch portion 26 engages side wall 35a at a point below the top wall 35b of channel portion 35. This assures that latch 15 has maximum opportunity to cock to effect the locking action. However, should latch portion 26a fail to engage side wall 35a, it would then back up into the corner between walls 35a and 3512, whereupon the locking action would take place as foresaid.
Preferably, also, the height of the latch portion 16 above portion 26 should tbe such that end 17 does not engage the top wall 34a of channel portion 34 as this might impede the locking action. Actually, the part of latch portion 16 above portion 26 serves mainly to prevent latch 15 from falling out of sash channel 14. In some applications that part may even lbe eliminated. In this event, latch member 15 is prevented from falling out of sash channel 14 by the engagement of latch portion 26 against channel wall 35h, extended as shown by dotted lines in FIGURE 4. In an alternative construction, that latch part may be retained to engage against the extended wall 35b during the locking action, whereupon latch portion 26 may be eliminated.
Often it is desirable that latch 15 be stamped out of a relatively hard material as compared with the material used to make the window frames, e.g. steel as compared with aluminum. The main reason for this is to provide a strong, rigid member which is able to withstand the stresses vdeveloped to support a relatively heavy glass window in a raised position. Utilization of such a hard latch 15 has an added advantage, however, in that it tends to score the window frame channel edge 31a forming a multiplicity of small knicks 38 thereon as shown in FIG- URE 4. Each knick is formed by the above-described wedging of edge 28 against channel edge 31a. Nicks 38 further minimize the likelihood of latch 15 disengaging from its selected position of adjustment on channel upright 31. In addition, however, they facilitate subsequent seatings of edge 28 on channel edge 31a when the Window is to be locked at the same raised position on channel upright 31. Similar notches (not shown) may be formed in wall 35a at the points where the wall is engaged by edge 26a of latch portion 26.
Still referring to FIGURE 4, as the window sash is raised, leading edge 28 of latch 15 slides freely upward along edge 31a and latch 15 is free to tilt or cock counterclockwise slightly within channel portions 34-36 until it assumes the extreme unlocked position :shown by broken lines in FIGURE 4. We have exaggerated the angle of tilt or cock of latch 15 for purposes of clarity. During the window-raising operation, spring 20 (FIG- URE 2) continues to hold edge 28 of latch 15 against channel edge 31a. However, latch 15 drops down in sash channel 14 until lower edge 18 of latch portion 16 engages bottom wall 36a of channel portion 36. The amount of counterclockwise tilt of latch 15 is limited by yengagement of edge 18 against the side wall 36h of channel portion 36. Edge 18 is set back from top edge 17 to place a limit on the extent to which latch portion 25 protrudes into vertical channel 11 when the window sash is raised. That is, if latch 15 were free to cock through a large angle, spring (FIGURE 2) might push latch portion 25 as far into channel 11 as it could go. This might then inhibit operation of the lock once the sash 12 is released.
When the window sash has been raised to the desired position, then, gravity pulling down on the sash forces leading edge 28 into frictional locking engagement with edge 31a as described above. Thereupon, latch 15 tends again to assume the vertical position shown by solid lines in FIGURE 4.
Latch 15a is a mirror image of latch 1S and operates in exactly the same way to secure the opposite side of sash 12.
Of course, other obvious modifications of the herein described window lock may be made without departing from the invention. For example, instead of mounting latches 15 and 15a in sash channel 14, they may be mounted in channel uprights 31-31 so -as to frictionally engage channel edges on the opposite sides ot window sash 12. In this event, the latches are located so that they engage sash 12 near the top thereof and the latches themselves are oriented upside down from their positions shown in FIGURES 1-4 so as to frictionally lock the window sash against downward movement. Otherwise, the arrangement and operation of the latches is much the same as described above.
1. A window comprising a sash trarne having a pair of normally vertical, oppositely disposed parallel sash receiving channels,
(A) a sash sliding substantially vertically 1n said sash trame channels,
(l) a horizontal channel in said sash,
(2) a pair of latch members slidably mounted in said horizontal channel,
(a) each of said latch a unitary stamping, (b) the clearance between said latch members and said horizontal channel being sufficient to allow limited rocking motion of said members about a generally horizontal axis within said channel,
(c) one end ot each of said latch members Ibeing bent about a generally horizontal axis into a plane forming an acute angle to the vertical, said bent ends being tapered so as to protrude at least partly into said vertical sash receiving channels, and
(B) spring means biasing each of said latch members laterally toward and at least partly into said vertical sash receiving channels, whereby the tapered edges of said latch members frictionally engage a portion of said vertical channels to prevent said sash from dropping from any position to which it may be slidably raised.
2. A window according to claim 1 including iinger gripping means on said latch members whereby said members may be manually retracted trom locking engagement with said vertical channels.
3. A latch of unitary construction comprising:
(A) a stamping loosely and slidably mounted in a horizontal channel within a sash,
(l) means biasing said stamping longitudinally within said channel in a direction tending to slidably remove said stamping from one end of said channel,
(2) the lateral clearance between said stamping and said horizontal channel being sufiicient to allow lateral motion of said stamping in a direction normal to said longitudinally biased direction,
members formed of (3) a tapered edge portion on the end of said stamping adjacent said one end of said channel, (a) said tapered portion of said stamping being bent along a horizontal axis into a plane at an acute angle to the vertical, whereby said tapered and angled portion is adapted to frictionally and lockingly engage an upright continuous edge of a sash frame and to lock the sash carrying said latch against downward movement while permitting upward movement of the sash. 4. In a window sash vertically slidable within a frame, latching means for securing the sash at any position to which it may be slidably raised, comprising in combination:
(A) a horizontal channel within the bottom portion of said sash, (B) at least one horizontally slidable latch member freely mounted in said horizontal channel,
(l) said latch member -formed of a unitary stamping,
(2) sufficient clearance being provided between said latch member and said horizontal channel to allow limited rocking motion of said latch member about a horizontal axis within said channel,
(3) a tapered end of said latch member being bent along a generally horizontal axis at an acute angle to the vertical and protruding at least partly from said horizontal channel to frictionally engage the frame, and
(C) spring means within said sash biasing said latch member horizontally toward and into rictional engagement with said frame, whereby said sash is securely held against the force of gravity at any position to which it may be slidably raised.
'5. An improved window and screen construction comprrsrng:
(A) a sash,
(B) a frame having a channel for supporting said sash for vertical sliding movement,
(C) a latch,
(l) formed of a single rigid piece,
(2) slidably mounted in said sash,
(3) tiltablc about a generally horizontal axis with in said sash,
(4) one end of said latch being bent about a generally horizontal axis into a plane forming an `angle with the vertical, said bent end being tapered so as to protrude partly into said channel, and
(D) a spring biasing said latch toward said channel into nonslip engagement with a portion of said channel so as to prevent said sash from dropping from any position to which it is slidably raised, said latch tilting about said axis out of said nonslip engagement when said sash is raised so as not to impede the upward movement of said sash.
6. An improved window closure comprising:
(A) a sash including a sash channel,
(B) a frame having a track for supporting said sash for vertical sliding movement,
(C) means dening an opening in said channel facing a portion of said track,
(D) a latch (l) formed of a single rigid piece,
(2) slidably mounted in said channel,
(3) having one edge protruding through said opening and engaging said track portion at an acute angle relative to the vertical,
(4) having a second edge engaging a wall of said channel, and
(E) a spring biasing said latch toward said track until said edges frictionally engage said track and said channel wall, respectively, so that (1) downward movement of said sash on said track produces a force couple at said edges which cocks said latch into nonslip wedging engagement with said track and said wall and thereby chocks said sash, and
(2) upward movement of said sash produces a force couple in the opposite direction at said edges which cocks said latch in the Opposite direction and thereby unchocks said sash which is then free to move up on said track.
7. An improved window closure as dened in claim 6 wherein:
(A) Said latch is made of relatively hard material and (B) said track portion is made of relatively soft material so that said wedging engagement of said rst edge against said track portion produces nicks in said portion which facilitate subsequent said engagements. 8. An improved window closure as dened in claim 6 wherein said latch includes:
(A) a plate whose opposite extremities constitute said edges, and
(B) means for supporting said plate at an elevated position in said channel.
9. An improved window closure as delined in claim 8 wherein said supporting means supports said plate at an acute langle with the vertical between 30 and 75.
10. An improved window closure as defined in claim 9 and further including means for retracting said latch away from said track in opposition to said spring to permit said sash to be lowered on said track.
References Cited UNITED STATES PATENTS 2,735,521 2/1956 Armerding 49-451 2,834,070 5/1958 Deats 49-451 2,852,817 9/ 1958 Howarth 49-451 XR 3,055,064 9/ 1962 Riegelman 49-451 3,179,454 4/ 1965 Mummendey 292-60 KENNETH DOWNEY, Primary Examiner.
U.S. Cl. X.R. 292-60, 67
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|U.S. Classification||49/451, 292/60, 292/67|
|Cooperative Classification||E05F11/00, E05F2700/04|