[0001] This invention relates to an adjustable bolt for locks, intended for installation
on sashes such as sliding door and window sashes.
[0002] Preferably, the invention is applicable to sashes fabricated from metal sectional
members, although it may be advantageously applied to wooden sashes or sashes of another
construction.
[0003] As is known, the problem is encountered with sliding sashes of how to hold the vertical
upright of the moving part, in the shut condition of the sash, as close as possible
to the corresponding vertical upright of the stationary part of the sash.
[0004] The two uprights are usually locked to each other by means of a bolt having one end
formed with a hook which protrudes from the vertical upright of the moving part and
engages with a ledge detent of a purposely provided housing in the opposite fixed
upright after passing through a slot cut in the upright wall.
[0005] The hooked bolt is part of the conventional mechanism that makes up a lock, also
mounted to the sash moving part, and is operated thereby through a handle or knob.
[0006] Its operation normally provides for just oppositely directed movements about a pivot
to engage with and disengage from the ledge detent.
[0007] It may be appreciated from the foregoing that a close fit between the upright of
the moving part and the upright of the fixed part, that is a good closure of the sash,
will be dependent on the amount of play present between the bolt hook and the ledge
surface with which it is to engage.
[0008] In prior art practice, that play is minimized on installation of the sash by the
use of one or more superimposed shim plates of different thicknesses, which are placed
on the abutment surface of the stationary part of the sash and secured thereon either
by adhesive means or screw fasteners.
[0009] This is a cut-and-try procedure which is less than fully satisfactory from an engineering
standpoint because it provides inaccurate adjustment of the play to be taken up due
to it being tied to the thickness dimension of the shim plate(s).
[0010] In addition, it takes a relatively long working time that weighs on the sash installation
costs.
[0011] The problem that undelies this invention is, therefore, that of achieving a close
fit between the moving and stationary uprights of a sash, that is a good closure thereof,
by a mechanism which can take up the play between the bolt hook and its ledge in a
fine and controllable way, the play take-up being carried out in a quick and precise
manner.
[0012] This problem is solved according to the invention by an adjustable bolt having a
hook-shaped working end and being characterized in that said hook-shaped end is fast
with a first element slidably coupled to a second element connected to a conventional
lock mechanism, a locking/unlocking means being provided between said first element
and said second element.
[0013] The invention will be now described in greater detail with reference to a preferred
embodiment thereof, as shown in the accompanying illustrative drawing, where:
Figure 1 is a vertical sectional view showing schematically a sliding-type sash in
the shut condition; and
Figure 2 is a vertical sectional view through the hooked bolt of this invention.
[0014] With reference to the above-detailed drawing views, the numeral 1 designates the
vertical upright of the stationary part of a sash of a kind fabricated, for example,
from conventional metal sectional members.
[0015] That upright has its wall 2, shown in section, with a surface 3 intended to face
mate with the surface 4 of the vertical upright 5 of the moving part of the sash,
with the latter in its shut condition.
[0016] The sliding movement of the moving part is indicated by a double-headed arrow F.
[0017] Conventionally mounted inside a purposely provided housing in the sectional member
which forms the upright 5 is a lock 6 whose outline is shown by dash lines in the
drawing.
[0018] That lock is provided with a bolt, generally indicated at 7, which is driven in a
conventional way by the lock mechanism on application of a rotary impulse to the square
pin 8 by means of a handle or knob, not shown.
[0019] The bolt 7 engages with the wall 2 of the fixed upright 1 by passing in an angularly
downward movement as viewed in Figure 1 through an opening 9.
[0020] The engagement of the bolt 7 with the wall 2 takes place between the surface 10,
facing the lock, of the hook-shaped terminating portion 11 and the surface 12 of the
wall 2.
[0021] With specific reference to Figure 2, it may be seen that the hook-shaped portion
11 of the bolt 7 is carried on a first tubular element 13 fitting slidably over a
second, rod-like element 14 which is connected to the lock actuating mechanism, not
shown because quite conventional.
[0022] That second element 14 has an inside threaded through-going hole 15 in which a setscrew
dowel 16 engages which has a drive head 17 and a pressure end 18 adapted to push down
on the inner surface 19 of the tubular element 13.
[0023] The latter is formed with a slot 20 which extends longitudinally in front of the
drive head 17 of the setscrew dowel 16 whose length is selected to allow its drive
head 17 to lie within the slot 20.
[0024] The cross-sectional shape of the tubular element 13 and the corresponding one of
the solid rod-like element 14 are preferably quadrangular.
[0025] It may be appreciated from the foregoing that, by backing out the setscrew dowel
16 from the hole 15 with a suitable tool (screwdriver) to be passed through the longitudinal
slot 20, the hooked portion 11 of the bolt can be made slidable over the element 14
to an appropriate position to produce a correct engagement of the surface 10 with
the ledge 12, thereby on shutting the sash, the surface 4 of the moving upright 5
can be brought to a close fit against the surface 3 of the stationary upright 1.
[0026] The dash-and-dot outlines shown in Figures 1 and 2 are the position attainable by
the hook 11 in consequence of its adjustment lengthwise of the element 14.
[0027] Once the best setting is found in relation to the thickness of the wall 2 of the
fixed upright 1, the setscrew dowel 16 is tightened down in its threaded hole, and
the pressure exerted by the end 18 on the surface 19 enables the setting to be retained.
[0028] Furthermore, the lay of the setscrew 16 with its drive head 17 inside the slot 20
ensures that, should the frictional engagement fail of the pressure end 18 with the
surface 19, as may be overcome in the instance of sliding sashes, the element 14 cannot
slip axially off the tubular element 13. This constitutes a safeguard against possible
attempts at forcing the sash open.
1. An adjustable bolt for sash locks, such as sliding door and window sashes, having
a hook-shaped working end and being characterized in that said hook-shaped end (11)
is fast with a first element (13) slidably coupled to a second element (14) connected
to a conventional lock mechanism, a locking/unlocking means (16) being provided between
said first element (13) and said second element (14).
2. A bolt according to Claim 1, characterized in that said locking/unlocking means
is a screw mechanism (16).
3. A bolt according to Claims 1 and 2, characterized in that said first element comprises
a tubular body (13) and said second element comprises a rod-like body (14) fitting
axially inside the cavity of the tubular body element, said second element (14) being
formed with an inside threaded cross hole (15) wherein a setscrew dowel (16) engages,
and said first element (13) being formed with a longitudinal slot (20) positioned
to align to said threaded hole (15) in the second element.
4. A bolt according to Claim 3, characterized in that said setscrew dowel (16) has
an axial length dimension exceeding the length of the cross hole (15), the drive head
(17) of said setscrew projecting into said longitudinal slot (20).
5. A bolt according to Claims 1 to 3, characterized in that the cross-sectional shapes
of said first and second elements are quadrangular.