GB2257745A - Cremone[espagnolette] fastening mechanism - Google Patents

Abstract

A cremone driver, particularly for use in an opening window or door. The driver has first and second racks 62, 64 oppositely driven upon rotation of a primary pinion 70, the primary pinion being engaged only with the first rack 62, with a secondary pinion 74 between the first and second racks to transmit drive from the first rack to the second rack. The teeth of the primary piston are arranged so as to prevent the primary piston being rotated from its locking condition by pressure from a rack. An improved cockspur type bolt 202 and mounting are disclosed, to provide multi-point locking, see fig. 23. Bolt 202 rotates to engage the frame of the door or window as in a cockspur, whilst the espagnolette bolts move rectilinearly. <IMAGE>

Description

CREMONE DRIVER AND LOCKING MECHANISM FIELD OF THE INVENTION This invention relates to a cremone driver and locking mechanism, and relates in particular to an improved cremone driver and locking mechanism for a window casement or door requiring multi-point securement.

BACKGROUND TO THE INVENTION The cremone driver and locking mechanism of the invention has especial but not exclusive utility for use within openable hollow-profile extruded (window or door) frames, the driver being protected therefore from environmental elements but required to operate even when located in such a restricted space.

DISCLOSURE OF THE PRIOR ART Espagnolettes were developed to permit multi-point one-way securement of pivoted (opening) panels, particularly of glazed window sashes; as is well known, such sashes can be glazed with one or more panes of glass i.e single glazed, double glazed etc.

When used with a hollow profile sash, the espagnolette drives are conventionally mounted externally of the profile.

A typical espagnolette is disclosed in British Patent 1,504,812, with securement for a top-pivoted sash positioned on the sash bottom rail (i.e. opposite to the sash pivot); the bolt element is moved into and out of securement behind a catch on the window frame horizontal (or transom), by an operating rod forming the rack of a "rack and pinion" drive. The espagnolette is mounted externally of the door or window, and a known problem with espagnolettes so situated is that heat expansion of the bolt element(s) and associated parts with the window open on a hot day can prevent window closure, with the bolt elements or rollers abutting or fouling the part mounting the keeper(s).

Another espagnolette arrangement is shown in British patent 1,499,831, wherein the espagnolette is mounted in the bottom sash rail but securement is at the window frame uprights (mullions).

A further alternative espagnolette is disclosed in our British Patent 2,161,208; we also disclosed a cremone (two-way) actuator using a drive-splitting rack and pinion arrangement comprising a pair of racks located to either side of the pinion, whereby the racks and thus the respective locking rods or bars are moved outwardly in opposite directions in response to rotation of the pinion, as by an operating handle.

An espagnolette bolt driver, also for instance a pair of two-way (cremone) multi-point shoot bolts as disclosed herein, may be fitted in a sash "upright" for a side mounted sash, or in a sash horizontal for a top mounted sash.

Whilst existing espagnolettes and in particular their drive mechanisms are satisfactory for many applications, they have disadvantages in addition to that above, and which for particular applications may be related, namely that they are relatively bulky, that they are not best suited for location within a chamber of proprietary profiles of different sizes where they are both concealed and protected from the environment, and that they are often not suited for applications requiring higher security.

A less bulky drive is thus required both for general use, and for higher security use, and preferably with design freedom to utilise additional and complementary security features. We have also realised that such a drive could be used for other applications, for instance a multi-point cockspur locking drive.

There is widespread concern at the ease with which unauthorised persons can gain access into a house, particularly by way of an opening reachable from the ground, perhaps a sash window; thus if the sash is secured only by a traditional cockspur (mounted on the sash lower rail, for instance as disclosed in GB 2,159,563A, and pivotally engaged behind a catch on the transom), or by securement means as disclosed in the above-mentioned British Patent 1,504,812, the house breaker or burglar can insert a tool between the sash and the transom, and lever the sash towards the pivot until the cockspur is lifted clear of the catch (so permitting the sash to be pivoted to its open condition without need to break the glass).There is also concern that the glass pane(s) may be removed, leaving the sash frame locked in position, and several designs of retaining clips for the glass have been proposed, for instance those of GB 2,233,697A and GB 2,228,964A; however, whilst the use of such clips has been widely advocated, they have not been found entirely satisfactory, and so many house builders (and particularly the authorities who supervise their work, for instance for public housing contracts) now specify "inside glazing" i.e. that the glass should be positioned in the sash from inside the building, in order that the normal glazing abutment on the sash rail can prevent subsequent removal of an unbroken glass pane from outside the building.Such "inside glazing" for a sash requires in particular a less bulky drive, particularly if the drive is to be concealed within a hollow sash profile as may furthermore be demanded for sashes in salt-spray areas corrosive to an exposed drive.

Whilst "inside glazing" has been found satisfactory for fixed windows, it has not heretofor we believe been taught how to incorporate a locking mechanism in an "inside glazing" sash.

Furthermore, it has not proved possible so far as we are aware to provide an "inside glazing" sash with locking bar securement means drivable to operate in both the fully closed and in a sash vented condition.

DISCLOSURE OF THE INVENTION It is an object of our invention to help solve the problem set out in the preceding paragraph by the provision of a locking mechanism, particularly a cremone driver, of reduced depth (parallel to the glazing chamber). Such locking mechanism (and preferably also the locking bars for shoot bolts) can therefore, when required, be fitted into or located by the stem portion of the standard sash rail, for instance one of T-section. The invention has particular application to windows having frame components of hollow-profile extruded synthetic plastic material such as uPVC, or of hollow-profile extruded metal such as aluminium, but in alternative arrangements can also be used with solid frames of timber or steel with the locking bars mounted externally of the sash, but the driver wherever possible sunk into the sash.

Thus according to one feature of the invention we provide a locking mechanism, particularly a cremone driver, which includes a primary pinion and first and second racks oppositely driveable upon rotation of the primary pinion, characterised in that the primary pinion drivingly engages only the first rack and in that a secondary pinion is located between the first and second racks whereby to transmit drive from the first rack to the second rack.

An advantage of our arrangement is that the displacement of the racks is controlled by the throw of the primary pinion acting with the first rack; thus this primary pinion no longer needs teeth around its entire periphery, and indeed can also therefore be positioned offset from the central axis of the cremone housing, to permit a reduced depth housing and/or a more convenient fixing position on or in the sash rail. A further advantage is that the primary pinion can engage housing parts as stops to determine the inward and outward positions of both racks. Another advantage is that the secondary pinion can be of small size, since there is no limitation of its freedom to rotate; thus it can readily be accommodated within a reduced depth cremone housing, particularly if the racks are suitably cranked. Yet a further advantage is that the driving tooth of the primary pinion can release from the driven rack in the locking condition, whereby attempted return movement initiated by a rack (as may be attempted by an unlawful intruder) is prevented by abutment of the driven rack with the driving tooth, whereby to provide "over-centre" restraint against movement of the racks in the respective opposed "unlocking" direction.

Usefully the racks are in sliding engagement at a position spaced from the secondary pinion, whereby the racks are located against lateral movement; such an arrangement can allow the use of a secondary "pivot" at an abutment position opposed to the pivot position for the secondary pinion i.e. to the opposite side of the primary pinion. In an alternative embodiment such secondary pivot can be directly engaged by one of the racks, usually the primary rack, to limit outward movement thereof (and thus by way of the secondary pinion outward movement of the secondary rack); the secondary pinion can also be used to limit inward movement of the secondary rack (and thus by way of the pinion inward movement of the primary rack).The primary pinion can alternatively be mounted on this secondary pivot, whereupon the primary pivot above described will become the abutment and the terminal control of rack movements reversed. Usefully the pivot(s) are provided by the interconnections joining two housing parts together.

As an alternative feature we provide a hollow profile sash which includes a cockspur mounted upon a pivot, characterised in that the pivot is within the profile. Usefully the cockspur is mounted upon a driven rack mounted in a metal housing located in the profile, the housing having an opening defined by edges with which the cockspur can abut to move it respectively into the sash retention condition and the sash release condition. Preferably the driven rack will be part of a locking system providing two point locking, so that the addition of the cockspur will provide three point locking, the three points being within the inside to outside depth of the window frame.

In an alternative arrangement one or more pivoted cockspurs can alternatively or additionally be mounted on a locking bar driven by a rack, the locking bar being (a) within the sash hollow profile e.g. for a sash built up from hollow profile sections of extruded plastics or metal, or (b} externally of the profile for solid sash members e.g. of wood, with usefully however the drive unit being itself sunk in a recess cut into the solid profile.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be further described by way of example with reference to the accompanying schematic drawings, in which: Fig.l is a perspective view of a house window arrangement incorporating upper and lower opening sashes and a non-openable side window; Fig.2 is a sectional view through a proprietary frame and sash; Fig.3 is a side view of a cremone sized to fit in the stem of a sash of extruded plastics material; Fig.4 is a view corresponding to that of Fig.3, but with the cremone in the locking (expanded) condition; Fig.5 is a side view of an alternative cremone; Fig.6 is a scrap view on the line VI-VI of Fig.5; Fig.7 is a side view of another embodiment of cremone; Fig.8 is a scrap view on the line VIII-VIII of Fig.7; Fig.9 is a side view of a further embodiment of cremone;; Fig.10 is a plan view of the secondary rack of Fig.9; Fig. 11 is a plan view of the upper (primary) rack of Fig.9; Fig. 12 is a side view of a cremone housing; Fig. 13 is an end view of a cremone housing; Fig.l4 is an end view of a primary pinion; Fig.15 is a scrap view from Fig.2, but with a profile internal cockspur; Fig.l6 is a perspective view of part of a rack, with a cockspur pivotally mounted thereon; Fig.l7 is an end view of a pivotally mounted cockspur; Fig.l8 is a side view of a cockspur suitable fo pivotal mounting; Fig.l9 is a side partial view of primary and secondary racks, with the secondary rack pivotally mounting a cockspur, the cockspur projecting from the housing into the retention condition;; Fig.20 is a side partial view of primary and secondary racks, with the secondary rack mounting an alternative cockspur, the cockspur being in its retracted non-retention sash condition, and indicating a further cockspur pivotally mounted on a locking rod; Fig.21 is an enlarged view of part of Fig.4, showing the "over-centre" abutment of a driven rack with a pinion tooth to prevent the rack from being pressed to the unlocked condition; Fig.22 is a scrap view showing the location of the locking mechanism in another profile; Fig.23 is of an alternative embodiment to that of Fig.19, with pivoting of a cockspur mounted on one rack being dependent upon cockspur engagement with the other rack; Fig.24 is a view of the cockspur of Fig.23 in the unlocked condition; Fig.25 is a detail view of part of the first rack of Figs 23,24;; Fig.26 is an enlarged view of another part of the first rack of Figs 23,24; Fig.27 is of an alternative cockspur arrangement; Fig. 28 is of the cockspur of Fig.28 in the unlocked condition; Fig.29 is of yet a further embodiment of cockspur arrangement; Fig.30 is of the cockspur of Fig.29, in the unlocked condition; Fig.31 is a detailed view of the secondary pinion and integral cockspur of Figs 29,30.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The window unit 10 has (a) an upper opening sash 12 i.e. a top opening window, (b) a lower opening sash 14 i.e. a side opening window, and (c) a full-sized non-opening window 16 i.e. a fixed light. The arrangement includes an external sill 18.

Sashes 12,14 have operating handles 20,21 - as seen viewed through the glazing in their sash opening positions-, and mounted on the inner faces (internally of the building) of the respective sash components 22,24 i.e. opposite the sash pivot axes 32,34.

The handles 20,21 are provided for use from inside the building, both for manipulating a sash between its closed condition and its open condition, and for operating securement means to hold the sash in its fully closed condition; in an alternative embodiment one or both handles 20,21 can also operate the securement means to hold the respective sash in a partly-opened (night vent) condition.

The invention will be described in relation to side opening sash 14, which closes against mullion 23, and against transoms 25,26.

As viewed in Fig.2, casement frame 30 of sash 14 closes in the direction of the arrow A towards the face 40 of the upstanding mullion 23. Casement frame 30 is constructed of four sections of hollow profile uPVC, extruded with hollow chambers designed for strength with lightness, and with mitred corner jointing; the profile (cross-section) of each section in this embodiment is of generally T-shape having an (outer) head 32 and inwardly directed integral hollow stem or shaft 34, but in an alternative embodiment is of generally L-shape; thus different extruders typically manufacture casement frames with proprietary profiles, as is well known in the art (see for instance the partial profile shown Fig.22).The stem 34 in this embodiment is divided into an outer hollow chamber 35 and inner and smaller hollow chamber 36, the outer hollow chamber 35 locating a metal strengthening bar 37 extending longitudinally along its length.

One surface defining the outer hollow chamber engages with a weather-seal 42 mounted on mullion 23, whilst one surface defining the inner hollow chamber engages with a combined weather and abutment seal 44.

Glazing 50, in this example a double-glazed window unit with the two glazed sheets spaced apart by separator 52, is sealed by resilient member 54 carried by outer head 32, and by resilient member 56 carried by a snap-in uPVC bead 58. During glazing, window 50 is fed from left to right as viewed in Fig.2, i.e.

from the inside of the building, into engagement with resilient member 54 (though this may be inserted subsequently), whereupon bead 58 is snapped into position as shown, from inside the building.

Although glazing 50 is shown with exaggerated clearance from stem 34, it will be understood that the glazing cannot be removed from the outside of the building, unless head 32 is removed from at least three edges of the glazing, which would be a long and laborious task. It will however also be understood that location of locking means on or in the stem and specifically within the smaller hollow chamber, requires a locking mechanism of reduced depth parallel to the plane of the glazing, than was required with the head 32 internally of the building.

It will be understood that the cremone driver will be mounted in a housing, suitably a metal housing, though for clarity the housing has been omitted from some of the drawings. Furthermore the (oppositely movable) racks will operate shoot bolts or equivalent, which in the extended, locking condition of the driver will typically engage in keepers or behind keeper plates in opposed fixed frame members surrounding the openable panel e.g. window, though again for clarity the shoot bolts are not shown.

Thus the driver is mounted in a two-part housing 100 (Fig.12, Fig.l3), with parts which can press-fit together to be.secured by studs 101, though in an alternative embodiment securement screws or bolts can be used; one of the housing parts has an aperture 102 to receive the drive shaft of an operating handle 21 (Fig.2).

The housing is open or has openings at its opposite ends, in this embodiment to permit extensions of a first or primary rack 62 (Fig.3 and Fig.ll) and a second rack 64 (Fig.3 and Fig.10) to project from opposite ends of the housing; these racks are then connected to locking rods (not shown but see Fig.20), the free ends of which typically comprise bolts which can engage in locking portions in upper and lower transoms 25,26; in an alternative embodiment the locking members project into the housing for internal securement to the respective racks.

The racks are driven by handle 21 (Figs 1,2) by way of primary pinion 70; primary pinion 70 has external teeth 72 which engage in corresponding recesses 73 (Fig.ll) in the primary rack, whereby to determine the throw of the gear i.e. the axial movement of the rack in response to a predetermined angular movement of the pinion.

Primary rack 62 is cranked at 66 to lead into a rack portion 67 which co-operates with freely-rotating secondary pinion 74, which in turn engages with secondary rack 64. Pinion wheel 74 transmits linear motion from primary rack 62 to secondary rack 64, as by aligned recesses 63,65 (Figs.10,11) whereby the racks can move together from the rest or non-locking condition of Fig.3, to the operative or locking condition of Fig.4.

Means can be provided to prevent excess movement of the racks in the locking and unlocking directions, in this embodiment by the engagement of first and second pinion abutment surfaces 70a,70b of primary pinion 70 with a housing abutment surface or surfaces. In an alternative embodiment this can be by engagement of cranked portions of one or both racks with internal housing abutments such as spacer pivot 50 (Fig.4).

As more clearly seen in the detail view of Fig.21, means are also provided to resist unwanted return movement of the first or primary rack (and thus by way of secondary pinion 74 of the secondary rack also) towards the non-locking condition. Thus the driving tooth 72 in the locking condition (Fig.4) adopts an "over-centre" condition relative to the primary rack 62, and so cannot be rotated by pressure from the rack in the unlocking direction (left to right as viewed in Fig.21).The surface 70a ensures that in the locking condition the anti-clockwise tooth as viewed in Figs 3,4 is engaged over-centre by the rack 62 to prevent clockwise rotation of the primary pinion by rightwards force from rack 62, whereby the engagement position relative to the rotational axis of pinion 70 prevents "imposed" rotation (from a rack) of the primary pinion from the Fig.4 condition to the Fig.3 condition.

An advantage of having cranked portions on the primary and secondary racks is that the rotational axis of the secondary pinion can be co-planar with the mating sliding surfaces 62a,64a of the racks. In the alternative embodiment of Fig.5, at least the secondary rack is not so cranked, permitting a reduced depth of housing, with an even smaller secondary pinion.

The "offset" cranks of Fig.7 permit the locking rods or bolts to pass to one side of a dividing wall which the housing 100 straddles; thus for a proprietary profile wherein chamber 36 as viewed in Fig.2 is divided by a horizontal extruded wall, whilst this horizontal dividing wall may need locally to be cut away to receive the locking mechanism or driver, the profile could be too weakened if all the dividing wall were removed i.e. for the full length of that section of the sash. Thus the locking rods in such embodiment are arranged to pass to one side or the other of the dividing wall, which is cut away only to receive the driver or the driver housing e.g. of Figs. 12,13.

In the further alternative embodiment of Fig.9, two secondary pinions 74 are used to ensure a fully balanced rack drive; the rack 62 is recessed to permit the primary pinion 70 to drive the rack 64, which in this embodiment thus becomes the primary rack.

In use, in the Fig.2 embodiment, the driver housing 100 is located in the inner (and smaller) chamber 36 of the stem 34 with the locking rods extending coaxially therein; these rods are typically connected by way of a keyhole slot 90 (Fig.6) in the respective rack, to receive by a twist and turn movement a rod T-end 92 (Fig.8). Thus with each rod presented as shown in Fig.8 to the keyhole, when the recesses are aligned with keyhole the rod is turned through 90 degrees so that the rod is trapped by the recesses.Alternatively the recesses can locate a one-way clip on the rod end, to prevent rod retraction from the respective rack, whilst attempted rod inward movement results in abutment with the rack; the rod is not turned and so this arrangement ("snap-lock") is suited to smaller rod-receiving chambers similar in size to those for acircular rods. In yet a further embodiment, the rod can carry known projections sized to fit into the recesses, whilst the rack has pinned thereto a C-clip or equivalent which can thereby hold the rod to the rack.

One of the rod end and rack end can have an angled projection which sprags with a recess on the other, to prevent unwanted relative movement.

At their remote ends the rods project through guides fixed in the upper and lower sash frame members, to engage in aligned keepers in transoms 25,26.

For assembly, a hole is cut in an upper or lower (as viewed in Fig.2) wall of inner chamber 36, of a short but sufficient length for the drive housing 100 to be inserted, whereupon the primary pinion is engaged (left to right) by an acircular (usually square or rectangular) drive shaft of handle 21, and which thereafter prevents or helps prevent the vertical removal of the housing through that opening.

It will be understood that my design of drive permits even smaller inner chambers 36 to be extruded if the profile designer so requires, for instance for aesthetically selected thin depth profiles, since only a short length of the inner (smaller) chamber 36 has its wall cut away; thus my housing can be allowed to project through openings made in one or both of the upper and lower walls of chamber 36 without significant weakening thereof.

Furthermore, as viewed in Fig.22, the shape of housing 100, with a narrow (upper) section for the primary pinion 70 and a wider (lower) section for the racks 62,64, allows the housing to be fitted internally even within difficult proprietary profiles.

Upright dividing wall 136 if present is cut away locally to accommodate housing 100, whilst the racks or rods are locally cranked so that the rods lie to the left or right of the dividing wall, generally as above described.

If desired, for additional security, handle 21 can also operate a cockspur mounted to pivot behind a catch 101 (Fig.15) conventionally secured to mullion surface 41, but it will be understood that such cockspur retention if used alone (without lock bar engagement in keepers in the transoms) could be aborted by the lifting of the sash frame 30 relative to window frame 40, i.e. away from mullion 23 as by the use of a known burglary tool.

The location of the locking rods in or associated with the inward chamber of the stem 34 permits the locking rods to be used either with the sash in the fully closed position as shown in Fig.2, or in a partly closed i.e. vent position, for instance with the locking rod engaging in keepers adjacent chamber 38 of the upper and lower transoms 25,26. However if a standard cockspur is to be fitted in the conventional position, as above described, the handle 21 needs to be cranked or otherwise shaped so as necessarily to extend a significant distance inwardly of the sash, and this may not always be desired.

As more fully described below, we thus propose an alternative cockspur 102 mounted on a pivot 103 located within the sash profile. As a further alternative feature we propose a cockspur assembly comprising an operating handle 21 and cockspur 102, wherein the handle 21 is indirectly connected to the cockspur 102 by (rack) means linearly movable upon handle rotation; thus the cockspur is "freely" pivotable relative to the handle. In a preferred embodiment the cockspur is constrained to move towards the sash retention and sash release conditions by respective abutments 104,105, though in an alternative embodiment (having only a single abutment) reverse cockspur movement from one of the conditions to the other can be energised by resilient means such as a torsion spring (not shown).

As seen in the embodiment of Fig. 19 the linearly movable means is the outer, usually secondary, rack 64. Rack 64 has an upstanding portion 106 carrying cockspur pivot 103 (Fig.17); the upstanding portion is usefully a portion cut and bent from the rack, as indicated in the embodiment of Fig. 16. Although cockspur 102 is U-shaped in end view (Fig.17), for balance about and two-position engagement with the pivot 103, in an alternative embodiment the cockspur can be a pivoted plate, of suitably hardened metal.

In the sash retention condition of Fig. 19, the cockspur has been moved to the right as viewed and has engaged the abutment 104, to pivot the cockspur clockwise, assisted in suitable dispositions by the weight of the cockspur; in some installations the cockspur weight alone may be sufficient to move it from one condition to the other, but I prefer a positive drive as by a torsion spring or engaged cam-abutment to effect this.

In the sash release condition of Fig.20, the cockspur has been pivoted anti-clockwise, by engagement with cam or abutment 105, in the housing wall. Whilst abutments 104,105 are formed in the "lower" wall as viewed i.e. remote from the glazing chamber, of the housing 100, in an alternative embodiment one or both can be formed in the outer wall 136 (Fig.15) of chamber 36, locally reinforced as necessary by a. metal insert and/or wall thickening. Thus such an arrangement can be used for a cockspur 102a (Fig.20), shown pivotally mounted to locking rod 107, externally of a housing 100.

In the embodiment of Figs 23,24, the cockspur 202 is mounted on drive gear assembly 203 (Fig. 26) of the first rack 262 and is pivoted by engagement with leading and trailing edges of an aperture in the second rack 264. The cockspur thus pivots between the locking condition of Fig.23 and the unlocked condition of Fig.24.

Primary pinion 170 has a first pinion abutment surface 170a which in use engages internal abutment surface 110 (Fig.24) of housing 100, to limit anti-clockwise (as viewed in Fig.23) rotation of the primary pinion. Primary pinion 170 also has two gear teeth 172; the anti-clockwise one of these teeth can be engaged in an over-centre condition by an angled stop surface 280 (Fig.26) on a tooth of the drive gear assembly 203 of first rack 262, whereby to prevent anti-clockwise rotation of the primary pinion by left to right pressure on the first rack, as might be attempted by an unauthorised intruder. Primary pinion 170 furthermore has an engagement surface 282 to limit locking (leftwards as viewed) movement of the first rack 262 i.e. to prevent first rack 262 and thus second rack 264 from being pulled free from the primary pinion after assembly.

First rack 262 has a support surface 290, angled rearwardly at between 5 and 20 degrees, in this embodiment at 8 degrees, to receive a corresponding surface 292 on the gear assembly 203; in use the gear assembly 203 is thus located between the side walls of the housing 100, between the primary pinion and the secondary rack, and against surface 290. In an alternative embodiment the secondary portion is positively coupled to the remainder of the first rack.

Return movement to the unlocked condition is transmitted from the primary piston (turned by anti-clockwise a key or equivalent in aperture 294) to the first rack by way of surfaces 290,292, and thence to the second rack by secondary pinion 74. The lower part of the secondary portion of the first rack sits within the depth of the first rack and opposed movement towards the locking condition is transmitted by surface 296 against the leading edge of the rack aperture.

In the embodiment of Figs 27,28 the cockspur 302 is mounted in an aperture in the second rack 364, for sliding movement with this rack between the locking condition of Fig.27 and the unlocked condition of Fig.28.

In the embodiment of Figs 29,30,31 we teach a combination cockspur and secondary pinion, whereby the integral pinion 302 will rotate (without leftwards or rightwards movement) with the secondary pinion 374, between the locking condition of Fig.29 and the unlocked condition of Fig.30.

In use, the cockspur will engage behind a keeper, such as keeper 109, having a first keeper face 109a (Fig.15) defining a fully closed sash condition, and a second keeper face 109b defining a partially open (night-vent) sash condition; the cockspur is thus concealed in the locked condition of the sash or casement frame. In this embodiment faces 109a,109b are integrally formed, but in an alternative embodiment are separate, or only face 109a is provided. The keepers can be of short length, as seen in Fig.l9, and do not need to extend the full length of the profile section; and are suitably retained against movement along the profile section as by being pinned or screwed to an extruded wall of the section. In each embodiment the cockspur is within the front-to-rear depth of the mullion 23, so that the protruding handle length necessary for a cockspur to engage an external keeper (such as keeper 101) is avoided.

Although the cockspur is shown pivotally mounted within profile chamber 36, if the sash is of solid sections e.g. planed wood, the pivot can be in a recess cut into the wood, suitably shaped to receive a drive as above described.

It will be understood that the cremone driver we now propose has space advantages as compared to known drivers. Since both racks are to one side of the pinion the housing can be of smaller depth; the housing can be of smaller width adjacent the primary pinion, and the handle for primary pinion rotation can usually be more readily fitted since the handle is offset from the racks.

Claims (16)

1. A cremone driver which includes a primary pinion and first and second racks oppositely drivable upon rotation of the primary pinion in which the primary pinion is drivingly engaged with only the first rack and in which a secondary pinion is located between the first and second racks whereby to transmit drive from the first rack to the second rack.

2. A cremone driver as claimed in Claim 1 in which the primary pinion has external teeth engaging in corresponding recesses in the first rack, whereby to determine the throw of the gear as herein defined

3. A cremone driver as claimed in Claim 1 or Claim 2 in which the primary pinion has first and second pinion abutment surfaces, and in which the driver is located in a housing having a housing abutment surface alternately engageable by the first and second pinion abutment surfaces.

4. A cremone driver as claimed in any previous claim in which the primary pinion has a first driving tooth, and in which the primary pinion has at least one additional driving tooth located anticlockwise relative to the driving tooth, and in which the said driving teeth extend part way only around the external periphery of the primary pinion.

5. A cremone driver as claimed in Claim 4 in which the said additional driving tooth is rotatable from a first or unlocked cremone condition to a second or locked cremone condition, said additional tooth in the cremone locked condition being in an over-centre condition whereby to prevent rotation of the primary pinion by way of a rack.

6. A cremone driver as claimed in any of claims 1-5 in which the first and second racks have mating surfaces in sliding engagement, and in which the said mating surfaces are in the same plane as the axis of the secondary pinion.

7. A cremone driver as claimed in any of Claims 1-6 in which the racks are rectangular in section, having one pair of opposed edges longer than the other pair of opposed edges, and in which the housing has a wider section sized to accomodate the one pair of opposed edges.

8. A cremone driver as claimed in Claim 1 in which two secondary pinions are provided, and in which the adjacent one of the racks has an opening through which the primary pinion drives the remote rack.

9. A cremone driver as claimed in any of claims 1-8 in which each rack has terminal connecting means for receiving and locating one end of a respective locking rod.

10. A cremone driver as claimed in any preceding claim, in which a handle used for rotation of the primary pinion is coupled to a cockspur whereby to provide a multi-point locking facility.

11. A cremone driver as claimed in Claim 10 in which the cockspur is mounted within the profile of a sash window, the cockspur having a securing blade portion which in the locked condition of the window is concealed.

12. A cremone driver as claimed in Claim 11 in which the cockspur is pivotally mounted on a rack, the housing having first and second engagement surfaces which position the cockspur respectively in a non-locking and locking condition, in accordance with the non-locking or locking position of the rack.

13. A locking mechanism which includes a cremone driver as claimed in any preceding claim, together with locking rods secured to the respective racks.

14. An opening panel, such as a window, which includes a locking mechanism as claimed in Claim 13.

15. A cremone driver constructed and arranged substantially as described with reference to any one of Figs.2-20.

16. An improved cockspur constructed and arranged as described with reference to any of Figs. 15-20.