GB2304803A

GB2304803A - Lockable push-to-release door or window fastener with a handle and snap-action spring biased latch with cam

Info

Publication number: GB2304803A
Application number: GB9618380A
Authority: GB
Inventors: Timothy Snee; Patrick Neary
Original assignee: BASTA HARDWARE Ltd
Current assignee: BASTA HARDWARE Ltd
Priority date: 1995-09-05
Filing date: 1996-09-04
Publication date: 1997-03-26
Anticipated expiration: 2016-09-04
Also published as: GB9618380D0; GB2304803B; IE80964B1; GB9518087D0

Abstract

A push-to-release fastener for a door or window comprising a handle 1 pivotably mounted 3,4 on a backplate 2 and a cylindrical latching member 11 mounted for displacement between a downward release position and an upper latching position in which a full-section portion 41 of the latching member 11 is positioned within a single recess 29 of the backplate 2 to resist turning of the handle 1. The latching member 11 has a single camming surface 34 for moving the latching member towards its downward release position during pivoting movement of the handle from its free position towards and into its retaining position. The single camming surface 34 engages against a cooperating camming surface 38 of the backplate 2 bordering the single recess 29 of the backplate 2. The latching member 11 is restored to its latching position by the action of a spring 12 on alignment of the latching member portion 41 with the recess 29 and is displaced into its downwards position to release the fastener by manual depression on the upper end of barrel 23. The recess 29 may open away from the handle pivot, or towards it as in the embodiment of Figs 11-16. A lip 32 located below flange 28 of the backplate 2 prevents the handle 1 being upwardly prised open.

Description

A FASTENER The present invention relates to a fastener, for example for a door or window.

The invention is especially directed to a fastener of the so-called push-to-release kind, in which the locking member or plunger is depressed to release the locked fastener. This construction contrasts with the more usual manner of provision of a locking feature in fasteners suitable for windows in particular, in which a locking member or plunger is depressed to engage or lock the fastener, and is released such as by key action for reverse outward or upward movement of the plunger or locking member into a position in which the fastener is once again unlocked. This reverse movement is typically activated by a compression spring and the locking or engagement movement of the plunger is thus effected by depressing the plunger against the compressive force of the spring.

There are attractions in the push-to-release structure, as compared with push-to-engage, especially for the user, and it is an object of the present invention to achieve an improved and advantageous push-to-release arrangement for fasteners of the kind to which the invention relates, and in particular for window fasteners.

A diversity of known arrangements exist directed to achieving a push-to-release capability, or an alternative equivalent mechanical structure. In EP-A-0,260,517, there is described a push-to-release structure in which a downward or depressing movement on the outer end of a locking plunger is converted internally within the plunger to an upward movement of a locking bolt at the lower end of the plunger structure by means of a gear arrangement comprising two linear gears or racks and an intermediate pinion. The first rack portion extends downwardly from the plunger top, while the second rack portion extends upwardly from the locking bolt. The structure is relatively complex, containing a large number of relatively small and potentially troublesome moving mechanical parts.In GB-A-2,019,481, a push-to-release feature is achieved by providing a pivoting locking member in the main body of the handle structure, in the vicinity of its pivot axis, mounted for locking movement for which it is biased towards a locking disposition. The locking member is urgeable out of the locking disposition into a release configuration by means of an elongate release member extending axially through the elongate shaft of the lever arm of the handle to a push button located at the outer extremity of the end of this lever arm. Again a multipart construction is in question, with a relatively long axial rod extending through the handle, this having therefore to be provided with a bore or hole to accommodate this further member. In addition, the location of the depressible plunger at the free end of the lever arm is relatively inconveniently placed for easy operation by a user.

GB-A-2,076,455 provides mechanical inversion of the push-to-release requirement by having a locking bolt which is slideably mounted for downward movement into a locking disposition under the urging of a compression spring, but is reversed into an opening dispositin by means of a trigger grip arrangement underneath the lever arm of the handle. While the number of moving parts is relatively few, and the trigger type grip has a measure of user convenience, a disadvantage is that the handle is required to be shaped so that its under-surface will be sufficiently spaced from the window or other feature on which it is mounted for the user to have adequate hand clearance between the lever arm and the window. This may necessitate a larger fastener structure or one which is disadvantageous in terms of design or appearance.

GB-A-2,188,671 provides a true push-to-release structure, in which a plunger is captively mounted in a bore of the handle. A cooperating escutcheon plate mounts a locking bolt which is urged upwardly and outwardly from the escutcheon plate by means of a compression spring, so that when a hole in the handle structure is aligned with the locking bolt, the bolt is urged upwardly under the spring pressure to latch into the hole in the handle, to thereby fasten the handle in a locked position. In this disposition, the plunger overlies the latch bolt, and to unfasten the handle, the plunger is depressed so that the locking bolt is in turn depressed until its top surface lies in or below the plane of separation of the handle and escutcheon plate. The handle may then be opened. There again results a relatively complex structure, in which locking is not achieved by the plunger in the handle.This serves rather to release the locked structure, locking itself being achieved by a separate component in the base plate or escutcheon.

GB-A-2,204,909 provides a further example of a true push-to-release window fastener structure, but again one in which a multipart mechanism is used. A vertically sliding latch member is mounted in a blind bore in the handle structure and biased by a compression spring into a condition in which a latching end engages in a cooperating recess in a base plate of the fastener structure. A separate push button assembly is mounted in a further open-ended bore of the handle structure, to meet the bore accommodating the vertically sliding latch member at an acute angle.A camming head of a push button structure mounted in this bore cooperates with a camming surface of the vertically sliding latch member, so that depression of the release button displaces the sliding latch member vertically out of its latching disposition in which its lower end engages the cooperating formation in the base plate. There is again provided a complex multi-part structure, with numerous moving components and a relatively complex bore structure in the handle, required to accommodate these various moving parts. GB-A-2,233,702 provides modifications of the handle assemblies of GB-A-2,204,909, but using the same basic mechanical structure.

GB-A-2,263,304 discloses a locking handle for a door or window in which a single latching member fulfills both the latching function and also comprises the depressible push button for release of the handle from the engaged condition. The latch is arranged to automatically engage when the handle is moved into the closed position to prevent subsequent movement of the handle to an open position until the latch is released. The latch consists of a push button feature at its upper end and is pivotally mounted on the handle with resilient biasing by spring means to urge its lower end, which defines the actual latching feature, into engagement with a recess of the fixing plate when the handle is in the closed position. Depression of the push button end of the structure releases the latch by rocking the button and latch against the resilient bias to move the bottom latching portion out of the recess in a direction which is substantially at right angles to the direction in which the button is depressed. The push button may be provided with a key-operated, axially displaceable, central locking plunger which is advanced from a retracted disposition within the button to a locking position in which it projects from the button, to engage a cooperating further recess in the fixing plate.

The number of components is reduced compared with the previous structures already identified, but the device suffers from the disadvantage that the push button pivots downwardly in a direction away from the thumb, when the handle is grasped by the hand, which may be found cumbersome in use. The construction again also provides a relatively complex multi-part structure, in particular in regard to the axial locking plunger feature.

GB-A-2,263,498 provides a further true push-to-release assembly, but again comprising a two-part structure. A latch member is pivotally mounted within the handle structure and is biased by a spring to engage a striker head of the latch member in a recess of the base plate. The latch member is pivotable to disengage the striker head from the recess of the base plate by depressing a plunger, which moves vertically. Vertical depression of the plunger causes the latch member, which is in the general form of a rocker arm, to pivot in a manner such that its striker head is moved away from the recess of the base plate. The handle may then be moved into an opening disposition of the structure, and the striker head is automatically reengaged with the recess on return pivotal movement of the handle to the closed disposition.This arrangement reverts to the multi-part construction of the earlier structures noted above, with the various complexities thereby entailed both as to number of moving parts and also as to manufacture of castings for the handle and base plate members.

In a further push-to-release fastener, which is distributed by Premier Hardware under the trade identification "Avon" and is the subject of Registered Design No. 2,046,052, a latch member is slideably mounted within the handle structure and is biassed in an upward direction by an internal spring. The lower end of the latch member is provided with opposed laterally extending cam or lug portions having upwardly directed camming surfaces. The baseplate is provided with cooperating downwardly directed camming surfaces defined by the lower edges of opposed flange portions bordering a transverse passageway across the width of the baseplate. Latching action takes place by the handle being pivoted towards the baseplate so that the lower end of the latch member passes into the transverse passageway.

During the entry movement, the upwardly directed camming surfaces of the axially displaceable upwardly biassed latch member cooperate in a camming manner with the downwardly directed camming surfaces of the baseplate, so that the latch member is pulled downwardly against the spring action. The camming surfaces in the baseplate extend inwardly from the sides of the baseplate and terminate at a pair of diametrically opposed recesses in the flange portions. the recesses extending through the flange portions bordering the through passageway in a direction parallel to the axis of the latch member. When the camming portions of the latch member become aligned with these recesses, the latch member snaps upwardly under spring force so that the camming portions or members become rotation-preventingly engaged within these recesses.In order to release the fastener, the axially upwardly biassed latch member is depressed downwardly by pushbutton action on its upper end, so that the camming portions at its lower extremity are pushed down to clear the sides of the recesses defined by the flange portions comprising the camming regions or surfaces of the baseplate, and the handle may then be pivoted sideways so that the latch member camming portions pass out of the transverse passageway.

In the latched position, the latch member camming portions engaging in the diametrically opposed recesses of the baseplate prevent rotation of the handle. In order to prevent forcing of the handle upwards out of its locked disposition in a direction substantially perpendicular to its normal plane of pivoting, thus breaking the handle assembly, a further cooperating flange of the handle assembly engages under a lipped or flanged upstand of the baseplate.

The majority of these various structures are capable of being locked in the closed disposition by incorporation of a key feature, as already partially adverted to above.

It is an object of the present invention to provide a further improved fastener of the push-to-release kind, and in particular an improved fastener of the kind incorporating a snap action camming latching engagement by downward axial movement of a latch member against a biassing spring force.

According to the invention, there is provided a push-to-release fastener for a wing member comprising a handle pivotably mounted on a backplate for pivoting displacement between a free disposition allowing pivoting of the wing member and a retaining disposition in which the wing member is held against pivoting movement, and a latching member mounted for translational displacement between a release disposition in which the handle may be pivoted relative to the backplate and a latching disposition in which a portion of the latching member is positioned for engagement with a cooperating portion of the backplate to resist pivoting of the handle relative to the backplate by mutual abutment of said latching member portion and said cooperating portion of the backplate, the latching member being biassed towards said latching disposition and having a single camming surface for moving the latching member in translation towards its release disposition during pivoting movement of the handle from its free disposition towards and into its retaining disposition by engagement of said single camming surface of the latching member against a cooperating camming surface of the backplate, said cooperating portion of the backplate being defined by a single recess extending through an edge region of the backplate, said single recess extending in a direction substantially axially parallel to the direction of translational displacement of the latching member, said cooperating camming surface of the backplate being defined to one side of said single backplate recess, between said single backplate recess and an edge region of the backplate, and said latching member being restored to its latching disposition by the biassing action on alignment of said latching member portion with single backplate recess.

Said translational displacement of the latching member may be limited in the direction towards the release disposition of the latching member by abutment of a head portion associated with the latching member against a surface region of the handle and may be limited in the direction towards the latching disposition of the latching member by abutment of a surface associated with the latching member against a further surface region of the handle. Said surface associated with the latching member may be defined by a spring-biassed disc or tumbler mounted in the latching member.

Said single camming surface of the latching member may be defined by an axial end surface of a substantially sectoral transverse recess in the latching member, said latching member portion for mutual abutment with said cooperating portion of the backplate being defined at least by a section of the latching member located between said substantially sectoral transverse recess in the latching member and an axial end face of the latching member.Preferably, the latching member is rotatable at least in its latching disposition between a first orientation in which said said substantially sectoral transverse recess in the latching member is directed towards a backplate flange portion comprising said single backplate recess and said cooperating camming surface and a second orientation in which a full-section surface region of the latching member is directed towards said backplate flange portion for engagement of said full-section surface region within said single backplate recess. In a favoured arrangement, the latching member is lockable in said second orientation in which a full-section surface region of the latching member is engaged within said single backplate recess.Rotation and locking of the latching member is suitably effected by insertion of a key into the latching member to release a latch barrel for rotation in known manner, for example, through 1800, from an unlocked condition into a locked condition. The latching member of the fastener of the invention is suitably urgeable towards said free disposition by manual pressure on an axial end of the latching member against the biassing action. In the locked condition of the fastener, the handle cannot however be moved from its retaining disposition on displacement of the latching member into the release disposition of the latching member, as engagement of the full-section surface region of the latch barrel within the backplate recess prevents lateral movement of the handle irrespective of the axial disposition of the latching member.

A cooperating camming surface may be defined to each side of said single backplate recess. In a particular embodiment especially suited to casement fasteners said single backplate recess is defined in a stepped axial end region of a generally elongate backplate. The handle may then have at least one lug portion to underlie said stepped axial end region of the backplate to resist the application of a prising force to the handle assembly. In one embodiment of the invention, said single backplate recess may open away from the axis of pivoting of the handle on the backplate. In an alternative embodiment, said single backplate recess may open towards the axis of pivoting of the handle on the backplate.

The invention also extends to a push-to-release fastener substantially as described herein with reference to and as shown in Figures 1 to 9, Figure 10, or Figures 11 to 16 of the accompanying drawings.

Particular advantages achieved by the construction of the invention are a reduction in the complexity of the various parts, especially in regard to the cast portions. In one embodiment, there may be achieved a combination of a push-to-release capability with resistance to forcing or other interference in a mechanically constructive manner.

Embodiments of the invention will now be described having regard to the accompanying drawings, in which Figure 1 is an exploded view of a push-to-release casement fastener according to the invention, Figure 2 is an end sectional view of the fastener according to Figure 1 in an about to engage disposition, in the axial plane of the latch member, Figure 3 shows the fastener in the disposition of Figure 2, in a side sectional view, substantially in the axial plane of the handle, Figure 4 is an end sectional view similar to Figure 2 of the fastener of Figure 1 during the engaging action, Figure 5 is a further side sectional view of the fastener substantially in the disposition of Figure 4, Figure 6 is a top sectional view of the cooperating locking elements of the fastener in an unlocked but engaged condition, in the general plane of the backplate flange.

Figure 7 is a view similar to that of Figure 6 showing the latching elements of the fastener in an engaged and locked disposition, Figure 8 is a side sectional view of the fastener in the disposition of Figure 7, for the depressed condition of the latch member, i.e. the configuration in which the fastener may be opened when not locked, Figure 9 is a top sectional view similar to Figure 6 of the cooperating latching elements of the fastener of Figure 1, in an unlocked and open disposition, with the latching member depressed, Figure 10 is an exploded sectional view of a push-to-release cockspur casement fastener according to the invention, Figure 11 is a side sectional view of a further embodiment of the fastener of the invention in an unlocked release or about to latch condition, Figure 12 shows the fastener of Figure 10 in a deadlocked condition with the key inserted, with the latch member in its upwardly biassed latching disposition, Figure 13 shows the fastener of Figures 11 and 12 in the unlocked but latched condition, Figure 14 is a view from below showing the functioning of the tumbler disc arrangements, in partial section, Figure 15 is a pictorial representation of the backplate recess region arrangement for the embodiment of Figures 11 to 14, and Figure 16 is an end view of the manner of engagement of the latch barrel or cylinder with the recess of Figure 15.

As shown in Figure 1, a push-to-release casement fastener according to the invention has a handle 1 mounted on a backplate 2 for rotation about an axis substantially normal to the backplate 2. A spigot type pivot 3 is provided on the handle 1 which engages in a cooperating aperture 4 of a boss 5 formed on the backplate 2, to permit the require rotation of the handle 1.The pivot axis or stud or shaft 3 of the handle 1 may be connected to a link or lock mechanism in conventional manner, to be actuated by rotation of the shaft portion 3 of the handle 1 within the raised portion or boss 5 of the backplate 2, thus enabling a door or window to which the fastener is secured to be released by rotation of the handle 1 out of alignment with the backplate 2 and resecured by returning the handle 1 into alignment with the backplate 2, "alignment" being defined by the axial or longitudinal direction of the handle being oriented to be the same as the axial or longitudinal direction of the backplate.

A through aperture 6 passing through the handle portion intermediate its gripping region 7 and the pivot axis 3 for connection to the backplate 2 defines a housing or accommodation region for locking and latching features of the structure. Aperture 6 has a lower region or portion 8 of substantially circular cross-section and an upper section 9 of generally rectangular shape with rounded corners. A nickel-plated zinc diecast barrel 11 is inserted into the housing region 6. The barrel 11 is also fitted with a tumbler disc or retain lever 13 and tumbler actuating spring 14, which arelaterally displaceable within a transverse passageway 18 of the barrel 11 relative to the barrel. The curved outer face 15 of the tumbler disc 14 mates with a recess in the wall of the housing aperture 6 in operation of the unit.Spring 14 engages between a laterally extending edge lip or flange at end portion 15 of tumbler "disc" 13 and an opposite end wall within barrel 11 to urge tumbler disc 13 radially outwards. When tumbler disc 13 is lined up with an axially extending groove in the inner wall of aperture portion 8, it moves radially outwards to engage in the recess or axial channel. When tumbler 13 is thus engaged, the barrel is locked against rotation, the axial recess or groove having only a limited circumferential extent, so that it effectively defines an axial slot in the wall. Tumbler disc 13 is withdrawn from its radially outward spring-biassed disposition by key action to release or unlock the fastener. Such mechanisms are well known in principle. The barrel 11 is inserted from below into the lower portion 8 of aperture 6.Maximum upward movement of barrel 11 is limited by a radially outwardly extending peripheral flange 16 on barrel 11 which underlies a radially inwardly extending flange or lip 17 of the through housing aperture 6 at the boundary between lower section 8 and upper aperture section 9. The upper face of flange 16 abuts the lower face or underside of lip 17 at the upper limit of barrel movement. A plastics generally rectangular barrel retainer or button 21 is then power-pressed together with a zinc diecast escutcheon 22.The button 21 and escutcheon 22, as fitted together to provide a single assembly, are then in turn fitted as a single unit to the upper axial portion 23 of the barrel 11, as positioned in the handle 1, in such a manner as to enable rotation of barrel 11 within retainer or button 21, and a spring 12 is located between the dished underside of the button or barrel retainer 21 and the upper surface of the internal lip or flange 17 within aperture 6, which separates the lower cylindrical portion 8 of the aperture 6 from the larger cross-section upper section 9, of substantially rounded corner rectangular shape. In the expanded or relaxed condition of spring 12, the retainer 21 is urged upwardly by the spring housed within the unitary assembly of the button or retainer 21 and the barrel 11.Thus barrel 11 and button or retainer 21, together with escutcheon 22, form a single axially displaceable assembly retained within aperture 6 for limited axial movement between an upper spring-biassed disposition in which barrel flange 16 abuts against lip 17 of the handle portion and an axially lowermost disposition relative to the handle in which the lower edge 24 of the button 21 abuts against the base of the upper aperture section 8, i.e. the region at least in part defined by the upper surface of lip 17. Downward depression of button 21 by finger or thumb action moves barrel 11 downwardly and is terminated by the stop action of button underside 24 coming into engagement against the upper surface of lip 17.For a barrel 11 fitted with a locking mechanism, as shown in the drawing, a key 25 provides for rotation of the barrel 11 between its locked and unlocked conditions, although a non-lockable mechanism may also be provided within the scope of the invention. Nickel-plating where provided for the barrel 11 and escutcheon 22 results in lower friction and resistance to scuffing.

The base or backplate 2 is provided with screwholes 26 for mounting it on a door or window. A flanged upstand 27 is provided at one extremity of the backplate 2, to underlie the handle 1 in an aligned position of handle 1 and backplate 2, and the upstand 27 terminates at its upper extremity in an axially extending flange 28, the plane of which is generally parallel to the general plane of the backplate 2, and the underside of which is spaced by approximately 4 mm at its laterally outer edges from the plane of the upper surface of the major portion of the backplate 2. The flanged portion 27 and flange 28 effectively define a stepped axial continuation of the backplate 2 extending in the general direction of the longitudinal axis of the handle, when the handle is aligned with the backplate.A substantially semicircularly shaped recess 29 is provided in the end face of this outwardly extending flange portion 28, recess 29 thus opening in the direction of the gripping portion 7 of the handle 1, when the handle 1 is aligned with the backplate 2, i.e. away from the axis of pivoting 4 of handle 7 on backplate 2.

The handle 1 is provided with a cooperating downwardly extending structure 31 having flange portions or lugs 32 to underlie the flange 28 of the backplate 2, in the aligned or closed condition of the handle 1, thereby preventing prising of the handle 1 upwards out of its closed condition.

In order to achieve push-to-release latching action, the lower end of the barrel 11 is provided with a transversely extending sectoral recess 33, which has a camming surface 34, rising upwardly from the side edges 35 of the transverse recess 33 towards a central raised portion 36. The shape of the sectoral cut-out 33 is thus such that there is a minimum thickness of material between the camming surface 34 of the recess or cut-out 33 and the bottom surface 37 of the barrel 11 towards the side edges 35 of the recess 33, and a maximum thickness of material at the centre 36 of this recess 33.

The downwardly directed surface 38 of the flange 28 of the baseplate upstand 27 is similarly provided with matching camming surfaces, such that the thickness of the flange 28 increases from the side edges 39 of the flange portion 28 towards the substantially semicircular recess 29 located between the wings 28a, 28b of the flange 28. The components are dimensioned such that when the barrel 11 is in its uppermost spring-biassed disposition, the recess 33 is aligned with the flange 28 of the baseplate upstand 27 in the transverse direction at rightangles to the axis of the barrel assembly, the camming surface 34 of barrel 11 then occupying substantially the same planar disposition as surfaces 38 of flange 28. Thus when the handle 1 is rotated to bring it into line with the baseplate 2, the protruding barrel portion at the underside of the handle engages, by means of the transverse recess 33, one or other of the wings 28a, 28b of the flange 28 of the upstand 27 of the baseplate 2. The upwardly sloping camming surface 34 of the recess 33 of the barrel 11 slides along the downwardly camming surface 38 of the wing 28a of the backplate flange 27, so that the barrel 11 is pulled down against the biassing spring 12 action until such time as the barrel 11 becomes aligned with the semicircular recess 29 in the backplate upstand 27. At this stage, the barrel 11 will snap upwardly so that the solid full diameter material 41 of the barrel below the slot or transverse recess 33 becomes engaged within the recess 29 of the baseplate 2.The handle 1 is then retained in this position until such time as it is required to release it.

Release is achieved by pushing down on the button 21 at the upper end of the barrel 11, in a direction perpendicular to the general plane of the handle 1, in other words in the direction of the axis of pivoting of the handle 1, which is also the axial direction of the latching assembly made up of barrel 11, button 21 and spring 12.

The barrel 11 is thus pushed downwards until the upwardly directed camming surface 34 of the transverse slot 33 in it is clear of the downwardly oriented camming surfaces 38 of the side wings 28a, 28b of the recessed flanged portion 28 of the baseplate upstand 27. The handle 1 is then free to rotate until such time as the barrel 11 is clear of the baseplate flange 28, when the button 21 may be released.

Deadlocking may be achieved by inserting the key 25 into the barrel 11 when the handle 1 and baseplate 2 are aligned and rotating the barrel 11 through 1800. The key 25 may then be withdrawn.

This locking arrangement provides greater security in that a greater mass of material of the barrel is applied to the locking function1 by virtue of the barrel being rotated until the non-recessed barrel body portion diametrically opposite to the recess 33 is positioned within the semi-circular recess 29 of the backplate upstand 27.

The invention provides a push-to-release fastener of simpler construction than any prior arrangement in which a barrel is pulled axially downwards during locking action, by means of camming engagement. Only a single-sided flange 27 structure is provided on the backplate. In the embodiment of Figure 1, the same flange structure 27 also cooperates with the underlying lip 32 of the handle assembly to prevent prising free of the handle by any lever action applied to the handle at rightangles to the plane of the backplate.

The underlying lip structure 32 of the handle portion is defined on the gripping portion 7 side of the aperture 6 by means of a downward extension of the handle material, to form an axially extended side wall region for the aperture 6 on the side thereof remote from the pivot axis 3. The handle lip structure 32 is provided by forwardly extending wing portions, comparable to those of the backplate, extending in a direction from the gripping region 7 of the handle 1 towards its pivot axis 3, to underlie the flange wings 28a, 28b of the backplate, in the closed condition of the handle structure.

Figures 2 to 9 inclusive show various stages of the locking and unlocking action, as well as the locked condition of the assembly.

In Figure 2, the handle 1 is being moved into position in alignment with the backplate, with a handle lip wing portion 32 overlying backplate wing portion 28b, and the camming surfaces 34, 28 of the barrel and backplate not yet in contact. In this disposition, the barrel 11 is in its uppermost axial location, under the action of spring 12. Figure 3 shows this orientation of the components of the system, in a side-sectional view.

Referring now to Figure 4, engaging action is progressing, and the camming surface 34 of the barrel 11 is being drawn downwards by its camming displacement across the downwardly directed camming surface 38 of the backplate flange 28 against the upward spring-biassing force acting on the barrel. Figure 5 shows substantially the same situation in side-sectional view. In Figure 6, full alignment of handle 1 and backplate 2 has been achieved, and the barrel 11 has sprung upwardly under spring action so that its full material section lower extremity 41 is now engaged within the semicircular recess 29 of the backplate upstand flange 28.In this orientation, the fastener is secured against lateral movement of the handle 1, but may be released by downward depression of the button 21 against the spring bias resulting from action on button 21 and the downward displacement of the barrel 11, these two components being integrally connected for unitary axial movement.

To secure full locking of the handle assembly, the barrel 11 is then rotated into the orientation shown in Figure 7, in which the axially continuous solid material section of the barrel 11 diametrically opposite the transverse recess 33 in its lower end region a which contains the camming surface 34, is aligned with and engaged in the semi-circular recess 28 of the backplate upstand 27.

The sectoral recess 33 is thus turned away from the backplate recess 29. In this condition, the handle 1 cannot be rotated away from the backplate, as camming action between barrel and backplate upstand is precluded. Figure 8 shows the fastener in the disposition of Figure 7, in a side-sectional view, with the latch barrel depressed.

Whether the latch barrel 11 is in its upper or outward latching disposition, or in its downward or inner release disposition, the handle when locked cannot be rotated away from the backplate, this being prevented by the axially continuous solid barrel structure in this region. In this dead-locked condition of the assembly, the barrel is prevented from rotation by the action of the tumbler 13, in accordance with wellknown arrangements for wing fasteners, and the required 1800 rotation of the barrel to bring it into the unlocked condition in which the fastener can be opened can only be achieved by key insertion and action. Tumbler 13 is outwardly biassed to engage in a cooperating axial slot in aperture portion 8. When the latch member or barrel 11 is in its unlocked condition, tumbler head 15 is diametrically opposite the locking axial slot. When barrel 11 is rotated 1800, tumbler head 15 enters the locking slot, preventing rotation, but not necessarily precluding axial movement. On insertion of the correctly profiled key, tumbler disc 13 is again withdrawn from the locking slot and the barrel can be rotated to free the fastener.

Finally, Figure 9 shows the fastener ready to be released, when the barrel 11 has been rotated back into an unlocked condition and the button 21 has been depressed, so that the transverse recess 33 of the barrel 11 is again aligned with the wings 28a, 28b of the backplate upstand 27 or flange 28. When the button 21 is depressed in this manner, the handle 1 can again be rotated to the side to release the fastener.

The manner in which the lip 32 of the handle 1 is located below the flange 28 of the backplate 2 in the aligned condition of the handle 1 and backplate 2 will be apparent from Figures 3, 5 and 8, and in particular from Figure 3. It will be appreciated that in this disposition therefore, any attempt to displace the handle 1 upwardly to try and prise it free from the backplate 2 by breaking the pivot 3 will be immediately resisted by abutment of the underlying lip 32 of the handle portion against the flange 28 of the backplate, in a mutually engaging force-resistant manner.

Figure 10 shows the arrangement of the invention as applied to a cockspur casement fastener, in which the reference numerals are the same as those of Figure 1, with the addition of 50 in each case, the structure being essentially similar, save only that there is single-sided entry 78a only to the latching recess 79, and also that the underlying interference preventing lip 31, 32 is not provided on handle 51, since security against breakage of the assembly by upward prising of the handle away from the baseplate is already available by virtue of the cock spur feature. Additional features present in the cockspur fastener not provided in the casement fastener of Figure 1 are a projection or lug 92 on the handle 51 for engagement in the apertured locking plate 93, in customary manner.Finally, since there is single-sided entry only to the latching recess 79, at wing 78a of baseplate upstand 77, a camming surface is provided on this wing only and not on the second wing 78b.

An alternative embodiment of the invention is shown in Figures 11 to 16. As shown in Figures 11 to 13 of these drawings, a push-to-release fastener according to the invention has a handle 101 mounted on a backplate 102 for rotation about an axis substantially perpendicular to the backplate 102. A pivot arrangement 103 provides for rotation of the handle 101 relative to the baseplate 102.

A through aperture passing through the handle portion intermediate its gripping region 107 and the pivot axis 103 for connection to the backplate 102 defines a region for accommodating the latching and locking cylinder or barrel 111 of the fastener. This through aperture has a lower region or portion 108 of substantially circular cross-section and an upper section 109 of generally rectangular shape with rounded corners. The barrel 111 is fitted with a locking disc or tumbler or retaining member 113, which is laterally displaceable within a transverse passageway of the barrel 111 relative to the barrel under the action of an actuating spring in the manner shown for a further retaining tumbler 116 in Figure 14.

The curved outer end face of the disc 113 in engages with a locking recess in the wall of the housing aperture 106 in operation of the fastener, in the locked condition thereof, in the manner previously described for the embodiment of Figures 1 to 9.

The barrel 111 is inserted in this embodiment from above into the lower portion 108 of the through aperture. Maximum upward movement of the barrel 111 is limited by a radially outwardly biassed disc 116 on the barrel which underlies the lower end of aperture portion 108, where it opens out into a region 117 of larger diameter within which there is a clearance between the downwardly extending cylindrical barrel and the periphery of the region 117, so that the radially outer end of disc 116 abuttingly underlies the periphery of aperture 108 around its mouth into region 117. Retaining disc or member 116 is biassed into this abuttingly engaging disposition for limiting upward axial travel of barrel 111 by an actuating spring 114, as shown in Figure 14, and is laterally displaceable within a transverse passageway 118 of the barrel 111.The upper face of disc 116 thus abuts the lower face or underside of the handle portion surrounding the mouth of aperture portion 108 at the upper limit of barrel movement and moves downwardly away from this face when the barrel is depressed. Disc 116 has a curved outer end face 115, similar to disc 113, which matches the curvature of the inner-wall of region 117. In the upward view of Figure 14, the location of the key 125 is also shown relative to a slot or aperture in disc 116. While the key does not act on disc 116, the drawing illustrates the relationship to apply between the key 125 and the similar locking disc 113.

A generally rectangular barrel retainer or button 121 is fitted to the upper axial portion of the barrel 111, as positioned in the handle 101, in such a manner that barrel 111 is rotatable within button 121, and a spring 112 is located between the dished underside of the button or barrel retainer 121 and the upper surface of the peripheral surround of the upper end of cylindrical aperture portion 108, at the mouth of aperture portion 108 within the larger cross-section upper aperture section 109. In the expanded or relaxed condition of spring 112, the retainer 121 is urged upwardly by the spring 112.Barrel 111 and button or retainer 121 thus form a single axially displaceable assembly retained within aperture 106 for limited axial movement between an upper spring-biassed disposition in which upward movement is limited by abutment of the projecting end region 115 of disc or member 116 against the peripheral underside of the handle body surrounding section 108 within enlarged region 117 and an axially lowermost disposition relative to the handle in which the lower edge 124 of the button 121 abuts against the base of the upper aperture section 109, i.e. the peripheral region surrounding the upper end of the aperture section 108. Downward depression of button 121 by finger or thumb moves barrel 111 downwardly and is terminated by the stop action of button underside 124 coming into engagement against the base of enlarged region 109. For a barrel 111 fitted with a locking mechanism, as shown in the drawings, key 125 provides for rotation of the barrel 111 between its locked and unlocked conditions.

The base or backplate 102 is provided with screwholes for mounting or a door or window. A flanged upstand 127 is provided at one extremity of the backplate 102, to underlie the handle 101 in an aligned position of handle 101 and backplate 102. The upstarrd 127 terminates at its upper extremity in an axially extending flange 128, the plane of which is generally parallel to the general plane of the backplate 102. The flange 128 extends from the upstanding flange portion 127 in the longitudinal or axial direction of the backplate, from an edge region of the backplate towards the pivot axis for the handle. Thus in the aligned condition of the handle and backplate, flange 128 extends in the general direction of the longitudinal axis of the handle also.A substantially semicircularly shaped recess 129 is provided in the end face of the inwardly extending flange portion 128, recess 129 thus opening away from the gripping portion 107 of the handle 101, when the handle 101 is aligned with the backplate 102, and towards the axis of pivoting between handle and backplate. The construction is thus similar to that of the first embodiment previously described, turned through 1800, so that the recess 129 now opens towards the pivot axis of the handle on the backplate rather than away from it, as in the case of recess 29 of the first embodiment.

In order to achieve push-to-release latching action, the lower end of the barrel 111 is provided with a transversely extending sectoral or substantially semicircular recess 133, which has again a generally dome-shaped camming surface 134, rising upwardly from the side edges 135 of the transverse recess 133 towards a central raised portion 136. The shape of the sectoral cutout 133 is thus such that there is a minimum thickness of material between the camming surface 134 of the recess or cutout 133 and the bottom surface 137 of the barrel 111 towards the side edges 135 of the cutout 133, and a maximum thickness of material in the region of the centre 136 of this recess 133. This arrangement again provides a double-sided self-actuating latch arrangement, for universal application in both right-handed and left-handed mounting arrangements.Alternatively, a construction may be provided in which a single-sided structure is provided with the greatest thickness of material being to one side only of the sectoral cutout, to provide a handed arrangement for latching cooperation by approach of the handle towards the backplate from one side only of the baseplate, as for the cockspur embodiment of Figure 10. - The downwardly directed surface 138 of the flange 128 of the backplate upstand 127 is similarly provided with matching camming surfaces, the thickness of flange 128 increasing from the side edges 139 of flange portion 128 towards the substantially semi-circular recess 129 located between wings 128a, 128b of the flange 128.The flange region and the barrel recess are dimensioned with respect to one another such that when the barrel 111 is in its uppermost spring-biassed disposition and the handle 101 is rotated to bring it into line with the baseplate 102, the protruding barrel portion at the underside of the handle engages, by means of the transverse recess 133, the wing region 128a of the flange 128 of the upstand 127 of the backplate 102. The upwardly sloping camming surface 134 of the recess 133 of the barrel 111 slides along the downwardly directed camming surface 138 of the wing 128a of the baseplate flange 127, so that the barrel 111 is pulled down against the biassing spring 112 action until such time as the barrel 111 becomes aligned with the semicircular recess 129 at the baseplate upstand 127.At this stage, the barrel 111 snaps upwardly so that the solid full diameter material portion 141 of the barrel below the slot or transverse recess 133 becomes engaged within the recess 129 of the baseplate 102. The handle 111 is then retained in this self-actuating locking disposition, until such time as action is carried out to release it.

Release is achieved by pushing down on the button 121 at the upper end of the barrel 111, in the direction perpendicular to the general plane of the handle 101, in other words in the direction of the axis of pivoting of the handle 101, which is also the axial direction of the latching assembly made up of barrel 111, button 121 and spring 112. The barrel 111 is thus pushed downwards until the upwardly directed camming surface 134 of the transverse slot 133 in it is clear of the downwardly oriented camming surface 138 defined by the side wings 128a, 128b of the recessed flanged portion 128 of the baseplate upstand 127. The handle 121 is then free to rotate until such time as the barrel 111 is clear of the baseplate flange 28, when the button 121 may be released.

Deadlocking may be achieved by inserting the key 125 into the barrel 111, when the handle 101 and backplate 102 are aligned, and rotating the barrel 111 through 1800. The key 125 may then be withdrawn, locking being achieved in the manner already described in connection with the earlier embodiment. This locking arrangement provides greater security and a greater mass of material of the barrel is applied to the locking function by virtue of the barrel being rotated until the non-recessed barrel body portion diametrically opposite to the recess 133 is positioned within the semicircular recess 129 of the backplate upstand 127, as shown in particular in Figure 12, i.e. the axially-continuous solid barrel section is engaged in recess 129.

In the deadlocked condition of the fastener, the upper locking disc is extended by means of its actuating spring to engage in the locking recess in the wall of the handle or aperture, so that the push-to-release action cannot be effected. In this embodiment, downward displacement of the latch member in the locked condition is feasible, the disc 113 end 115 moving along the axial slot, but this possibility may also be excluded, if desired. The locking displacement or action of the disc or locking member into its locking disposition is effected in known manner by spring 114 and unlocking is achieved by lateral movement of the disc under the action of an appropriately profiled portion of the key against the bias of the spring, to enable rotation of the barrel through 1800. The spring is then no longer effective to implement any locking action, in that the disc or member is not then aligned with a locking or retaining aperture or slot.

As in the case of the first embodiment, the invention provides a push-to-release fastener of simpler construction than any prior arrangement in which a barrel is pushed axially downwards during locking action. The single sided flange 127 structure provided on the baseplate is identical in action to that of the first embdiment, save only that the recess in the base plate for cooperation with the locking end of the barrel is oriented to open in the direction of the pivot axis of the handle on the baseplate, rather than in the opposite direction.

Thus, as in the first embodiment, the handle is displaceable by pivoting action between a free disposition and a retaining disposition. In the retaining disposition of the handle, the latching member is displaceable between a release disposition, Figure 11, and a latching disposition, Figure 13. The latching member or a portion of it, e.g. the barrel, is also rotatable, when in its latching disposition, between a locking disposition, Figure 12, and an unlocked but latching disposition, Figure 13. In the locked configuration of Figure 12, the latching member may also be displaced axially between its latching and release dispositions, without however enabling unlatching to allow pivoting of the handle into its free disposition. The locking tumbler is biassed outwardly into a locking axial slot or recess in the locked condition, from which it may be withdrawn against spring action by a key, Figure 12.

Claims

1. A push-to-release fastener for a wing member comprising a handle pivotably mounted on a backplate for pivoting displacement between a free disposition allowing pivoting of the wing member and a retaining disposition in which the wing member is held against pivoting movement, and a latching member mounted for translational displacement between a release disposition in which the handle may be pivoted relative to the backplate and a latching disposition in which a portion of the latching member is positioned for engagement with a cooperating portion of the backplate to resist pivoting of the handle relative to the backplate by mutual abutment of said latching member portion and said cooperating portion of the backplate, the latching member being biassed towards said latching disposition and having a single camming surface for moving the latching member in translation towards its release disposition during pivoting movement of the handle from its free disposition towards and into its retaining disposition by engagement of said single camming surface of the latching member against a cooperating camming surface of the backplate, said cooperating portion of the backplate being defined by a single recess extending through an edge region of the backplate, said single recess extending in a direction substantially axially parallel to the direction of translational displacement of the latching member, said cooperating camming surface of the backplate being defined to one side of said single backplate recess, between said single backplate recess and an edge region of the backplate, and said latching member being restored to its latching disposition by the biassing action on alignment of said latching member portion with single backplate recess.

2. A push-to-release fastener according to Claim 1, wherein said translational displacement of the latching member is limited in the direction towards the release disposition of the latching member by abutment of a head portion associated with the latching member against a surface region of the handle and is limited in the direction towards the latching disposition of the latching member by abutment of the surface associated with the latching member against a further surface region of the handle.

3. A push-to-release fastener according to Claim 2, wherein said surface associated with the latching member is defined by a spring-biassed disc or tumbler mounted in the latching member.

4. A push-to-release fastener according to any preceding claim, wherein said single camming surface of the latching member is defined by an axial end surface of a substantially sectoral transverse recess in the latching member, said latching member portion for mutual abutment with said cooperating portion of the backplate being defined at least by a section of the latching member located between said substantially sectoral transverse recess in the latching member and an axial end face of the latching member.

5. A push-to-release fastener according to Claim 4, wherein the latching member is rotatable at least in its latching disposition between a first orientation in which said said substantially sectoral transverse recess in the latching member is directed towards a backplate flange portion comprising said single backplate recess and said cooperating camming surface and a second orientation in which a full-section surface region of the latching member is directed towards said backplate flange portion for engagement of said full-section surface region within said single backplate recess.

6. A push-to-release fastener according to Claim 5, wherein the latching member is lockable in said second orientation in which a full-section surface region of the latching member is engaged within said single backplate recess.

7. A push-to-release fastener according to any preceding claim, wherein the latching member is urgeable towards said release disposition by manual pressure on an axial end of the latching member against the biassing action.

8. A push-to-release fastener according to any preceding claim, wherein a cooperating camming surface is defined to each side of said single backplate recess.

9. A push-to-release fastener according to any preceding claim, wherein said single backplate recess is defined in a stepped axial end region of a generally elongate backplate.

10. A push-to-release fastener according to Claim 9, wherein the handle has at least one lug portion to underlie said stepped axial end region of the backplate to resist the application of a prising force to the handle assembly.

11. A push-to-release fastener according to any preceding claim, wherein said single backplate recess opens away from the axis of pivoting of the handle on the backplate.

12. A push-to-release fastener according to any of Claims 1 to 10, wherein said single backplate recess opens towards the axis of pivoting of the handle on the backplate.

13. A push-to-release fastener substantially as described herein with reference to and as shown in Figures 1 to 9 or Figure 10 of the accompanying drawings.

14. A push-to-release fastener substantially as described herein with reference to and as shown in Figures 11 to 16 of the accompanying drawings.