WO1998015705A1

WO1998015705A1 - A locking mechanism

Info

Publication number: WO1998015705A1
Application number: PCT/NZ1997/000130
Authority: WO
Inventors: Michael Gerard Francis; Damon Gregory Burwell
Original assignee: Interlock Group Limited
Priority date: 1996-10-07
Filing date: 1997-10-06
Publication date: 1998-04-16
Also published as: CN1232523A; EP0929729A1; AU4638997A

Abstract

A locking mechanism suitable to lock a closure element such as a window frame. The mechanism is formed by a sliding bolt (18) and a locking striker (10), the sliding bolt having at least one projection (27). The striker (10) has an abutment (11) which is engageable with the projection (27) to effect a locking action. The abutment (11) has an overhang (26) which is engageable with an overhang (28) of the projection (27) to maintain the locking action in the event that a torque or twisting action is applied to the sliding bolt/striker when in the locking position.

Description

A LOCKING MECHANISM

BACKGROUND OF THE INVENTION

This invention relates to a locking mechanism.

With outward opening windows it is common practice to have a

locking mechanism at the side of the window opposite to the

hinged side so as to lock the window in a closed position.

Such a locking mechanism can be of an espagnolette type where

a central handle operates locking bars or connectors which

cause a bolt associated with each locking bar to interact

with a striker to create the locking effect . With such an

arrangement, the striker can be a mounting plate with an

upstand and the locking bolt can be a pin or other projection

which, when moved by the connector, moves behind or away from

the projection of the striker to effect locking or unlocking

as the case may be .

Problems can arise with known forms of bolts and strikers .

For example, an outward force applied to a window, eg during

unauthorised entry or as a consequence of a negative pressure

in extreme wind conditions can cause an interaction between the pin of the locking bolt and the striker. This can lead

to a twisting of the bolt relative to the striker so that the

pin adopts an angle to the striker projection whereby the pin

slides over the projection resulting in loss of the locking

effect . Such forces can also apply high loadings on the

projection of the striker with the result that the striker

can break usually by fracturing of the mounting plate about

the base of the projection. Once again, loss of the locking

effect is the outcome.

A further problem which can arise is a lack of smoothness or

binding of the pin as it moves relative to the strike. This

can occur due to the particular configuration of the bolt and

strike or as a consequence of loadings arising from the

wedging action which normally takes place to ensure that the

lock side of the window is drawn firmly onto the window

seals .

SUMMARY OF THE INVENTION

It is an object of the present invention to provide

improvements in locking mechanisms which include a bolt and

strike so as to at least go some way to overcoming the aforementioned problems or at least providing the public with

a useful choice .

In one broad aspect of the invention there is provided a

locking mechanism comprising a sliding bolt and a locking

striker, the sliding bolt having at least one projection

which is engageable with an abutment of the striker to effect

a locking action, there being retaining means for retaining

the locking action in the event of a torque applied to the

bolt and/or striker when in the locking position.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective view of a locking striker

according to a first form of the invention,

Figure 2 is a perspective view of a sliding bolt

according to the first form of the invention,

Figure 3 is a perspective assembly view of the locking

striker and sliding bolt of Figures 1 and 2, Figure 4 is a perspective view of a locking striker

according to a second form of the invention,

Figure 5 is a plan view of the locking striker as shown

in Figure 4 ,

Figure 6 is a perspective view of the locking striker of

Figures 4 and 5 in combination with a sliding bolt

according to the second form of the invention the

relative disposition being shown in a locking position,

Figure 7 is a similar perspective assembly view to

Figure 6 of the second form of the invention but from

the opposite side, and

Figure 8 is a similar view to Figure 6 but showing the

locking striker and sliding bolt in an unlocking

position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to Figures 1 to 3 the locking striker 10 is

according to the preferred form of the invention of die cast zinc construction. The striker 10 includes a plurality of

abutments 11 which are spaced apart by openings 12. In the

preferred form of the invention each opening 12 has an

inclined or ramp surface 13 extending up to the floor 14 of

the striker.

Spaced from the abutments 11 is a back wall 15 which has a

pair of spaced apart projecting portions 16 which are located

opposite the openings 12.

In the floor 14 of the striker 10 are a plurality of openings

17 through which mechanical fasteners can be engaged to mount

the striker to, say, the frame of a window.

The sliding bolt 18 as shown in Figure 2 comprises an elongate base 18 from each end of which project flanges 19.

Pins 20 on flanges 19 are provided for coupling the sliding

bolt to a coupling rod and/or corner transmission of a

typical espagnolette or multi-point locking mechanism. In

the form illustrated the base 18 has projecting edges 21

which engage in a sliding manner in a groove of a window sash

in once again a typical espagnolette or multi-point locking

arrangement . Projecting upwardly from the base 18 are projections 27

formed by a pair of pins 22 on which are preferably rotatably

located rollers 23. In a preferred form of the invention the

sliding bolt is of die cast zinc construction with stainless

steel rollers .

As shown in Figure 3 the rollers 23 pass through openings 12

in the striker when the window with which the locking

assembly is mounted moves to the closed position. The ramp

portions 13 can assist in correct entry of the rollers

through openings 12.

Upon longitudinal movement of the sliding bolt in either of

the directions shown by the arrows in Figure 3 the rollers 23

engage with the angled edges 24 of the abutments 11, this

causing a lateral movement of the sliding bolt body 18 which

as is normal with locking assemblies of this type pushes the

lock side of the window sash firmly against the seals of the

window frame .

The rollers thus become located between abutments 11 and the

opposing surfaces 25 of the back wall 15 between the projecting portions 16. In the preferred arrangement the

distance between the abutment face 11a and the back wall

surface 25 is just slightly greater than the external

diameter of the roller 23. As a result the rollers 23 are

snugly located within the striker 10.

As a consequence if any torque or twisting action is applied

to the locking assembly or more particularly the striker such

torque or twisting action is resisted by the snug fit of the

roller 23 between abutment face 11a and back wall surface 25.

Consequently, the roller 24 is not able to be twisted to an

angle whereby it can slip out of the locking striker.

The angled surfaces 24 and the corresponding sloped surfaces

24' of the projecting portion 16 are in the preferred form of

the invention at an acute angle to provide a long lead-in for

smooth movement of the rollers into the locking position

between faces 11a and 25. This long acute angle lead-in

together with the big diameter rollers provide for a smooth

action as the locking assembly moves between locked and

unlocked positions. A further advantage of the plurality of rollers, or pins 22

if rollers 23 are not present, is a sharing of load which is

particularly advantageous when the locking assembly is used

with heavy weight sashes such as those up to 160kg in weight.

The locking assembly is also of particular advantage in such

situations in that the entrapment of the rollers 23/pins 22

provides good resistance to any opening force such as a

negative pressure force in high or extreme wind conditions.

The locking assembly is also non-handed. As can be shown in

Figure 3, the locking effect can be achieved irrespective of

the direction of longitudinal movement of the sliding bolt.

Figures 4-8 show a second embodiment of the invention in

which like components are identified by the same reference

numerals as used in Figures 1-3.

As can be seen in Figures 4 and 5 the striker 10 simply

provides a plurality of abutments 11, the top surface of

which, however, is extended to provide an overhang 26. As

can also be seen, the overhang 26 follows the contour of the

lead-in surfaces 24 and abutment surface 11a. As with the

first described embodiment the lead-in surfaces 24 are at an acute angle, though preferably more acute than the first

embodiment, to thus provide a long lead-in portion.

The sliding bolt as shown in Figures 6 to 8 has a plurality

of fixed projections 27 in place of the pins 22/rollers 23 of

the first embodiment. The projections 27 are of the same

general configuration as the abutments 11 of the striker 10

and thereby have overhangs 28.

As shown in Figure 8 the projections 27 once again engage

between the pairs of abutments 11 when the window moves to

the closed position whereupon the sliding bolt can be moved in either of the directions shown by the arrows to cause the

projections 27 to move into an opposing face to face

engagement with the abutments 11 (see Figures 6 and 7) . In

doing so, the overhang 28 of each of projections 27 of the

sliding bolt 18 engage beneath the overhangs 26 of abutments

11 of the striker 10. This provides a positive interlocking

of the striker and sliding bolt such that if a torque or

twisting action is applied as previously described the

overhangs 26 and 28 resist any separation of the sliding bolt

from the striker. The long acute angled lead-ins of the projections 27 and the

abutments 11 provide a smooth sliding action as the sliding

bolt moves to and from the locking position. With the three

points of contact arising from the three separate abutments

11 and projections 27 of the sliding bolt there is a positive

and strong interengagement between the striker and the

sliding bolt thereby making the locking assembly particularly

useful in situations where a heavy weight sash is to be

locked in the closed position and where high negative

pressures may be experienced in extreme or high wind

conditions .

Claims

1. A locking mechanism comprising a sliding bolt (18) and a

locking striker (10) , the sliding bolt having at least

one projection (27) which is engageable with an abutment

(11) of the striker to effect a locking action, there

being retaining means (25 or 26) for retaining the

locking action in the event of a torque applied to the

bolt and/or striker when in the locking position.

2. A locking mechanism as claimed in claim 1 wherein the

striker (10) includes at least a pair of abutments (11)

spaced apart such that a said projection (27) can pass

therebetween in a first direction, at least one abutment

(11) being spaced a distance from a surface (25) , there

being guide means (24, 24') to guide said projection

(27) in a second direction to locate between said

abutment (11) and said surface (25) , said distance being

slightly greater than the cross-sectional thickness of

the projection (27) between said abutment (11) and said

surface (25) .

3. A locking mechanism as claimed in claim 2 wherein the

projection (27) is formed by a pin (22) and roller (23)

rotatably mounted therewith.

4. A locking mechanism as claimed in claim 2 wherein the

projection (27) includes a roller.

5. A locking mechanism as claimed in claim 2 further

including a limit means (16) to limit the extent of

movement of the projection (27) in said first direction.

6. A locking mechanism as claimed in claim 5 wherein the

guide means includes opposed guide surfaces (24 and 24')

which extend at an acute angle relative to said first

direction.

7. A locking mechanism as claimed in claim 2 further

including ramp means (13) in the space between said

abutments (11) .

8. A locking mechanism as claimed in claim 1 wherein the

striker includes at least a pair of abutments (11)

spaced apart such that a said projection (27) can pass therebetween in a first direction, the sliding bolt (18)

having at least one projection (27) , at least one said

abutment (11) and the projection (27) having engagement

means (26 and 28) which are interengageable when the

sliding bolt (18) is moved in a second direction to the

locking position where the abutment (11) and projection

(27) are located in an opposing disposition and if a

said torque is applied to the sliding bolt and/or

striker.

9. A locking mechanism as claimed in claim 8 wherein the

engagement means includes an overhang (26 and 28)

extending from the abutment (11) and projection (27)

respectively.

10. A locking mechanism as claimed in claim 9 wherein a said

overhang (26, 28) extends from a distal end of the

respective abutment (11) and projection (27) .

11. A locking mechanism as claimed in claim 8 wherein at

least one of the abutment (11) or projection (27)

includes an abutment surface (11a) which is engageable

with an engagement means (28) of the respective projection (27) or abutment (11) when in the locking

position if relative movement occurs substantially in

said first position to release the sliding bolt (18) from the striker (10) .

12. A locking mechanism as claimed in claim 8 or 11 wherein

at least one of the abutment (11) or projection (27)

includes a lead-in surface (24) which is engageable with

the projection or abutment as the case may be during

sliding movement of the bolt (18) substantially

transverse to said first direction.

13. A locking mechanism as claimed in claim 12 wherein the

lead-in surfaces (24) are located at an acute angle

relative to said first direction.

14. A locking mechanism as claimed in any one of claims 1 to

12 wherein the striker (10) is provided with mounting

means (17) whereby the striker is mountable in a fixed

manner to a first structure and the sliding bolt (18) is

provided with locating means (21) whereby it is

slidingly mountable with a second structure, the first and second structure being movable relative to one

another .

15. A locking mechanism as claimed in claim 13 wherein the

sliding bolt (18) includes coupling means (20) for

coupling the sliding bolt (18) to sliding control means.