GB2414513A

GB2414513A - Restrictor with lockable pivoted catch

Info

Publication number: GB2414513A
Application number: GB0510439A
Authority: GB
Inventors: Andrew Michael Dean; Michael George Mander
Original assignee: DYNATECH ENG Ltd
Current assignee: DYNATECH ENG Ltd
Priority date: 2004-05-25
Filing date: 2005-05-23
Publication date: 2005-11-30
Anticipated expiration: 2025-05-23
Also published as: GB0510439D0; GB2414513B; GB0411590D0

Abstract

A restrictor device comprising a base 10 and a catch 11 pivotally mounted on the base and biased to engage an abutment 21. The catch comprises a slot 26 that has an exit. The catch is locked by a member 12 that, in a normal state, blocks the exit and, when manually moved to a release state, opens the exit. The slot 26 may define two arms. The locking member 12 may comprise a lever that is pivotally mounted at an end of one arm and biased to its normal state. This one arm of the device or the entire catch 11 may be laminated. The device is designed to restrict opening of a window to a certain amount. To release the restrictor, a two-handed operation is required, which is said to make it difficult for a young child to release the lockable member to the release state.

Description

Restrictor Device This invention relates to a restrictor device for

restricting the opening of a window hingedly mounted in a frame.

Window restrictors are well known in which, in use, a peg on a component fixed to the window frame is received in a slot in a body part of the restrictor which is pivotally mounted on a base component fixed to the window and spring biased to a rest position. Upon opening of the window by a relatively small amount, i.e. for ventilation purposes, there is relative movement of the peg along the slot until it reaches an end thereof at which a retaining hook is formed, which prevents further relative sliding movement of the peg and thus restricts the degree of opening of the window. To open the window further, the window is slightly closed and the hook then manually disengaged through an opening in a side of the slot from the peg. Upon closing the window from its further opened position, the peg initially engages the restrictor body part to pivot it against its bias and allow the peg to re- enter the slot therein. The body part then 'springs back' to its rest position, so that as the window continues to be closed, the peg travels along the slot until the window is fully closed.

A disadvantage of such a restrictor is that it is relatively easy for the restrictor body part to be disengaged from the peg and thus to allow full opening of the window. In particular this represents a danger as far as young children are concerned in that they may fully open the window and fall therefrom. Although the danger of a young child overcoming the restrictor on window opening could be removed by providing some form of key lock - 2- on the restrictor, this solution is disadvantageous in requiring a special key to be kept and used at least each time extended opening of the window is required.

An object of the invention is to provide an improved restrictor device in a convenient and effective manner.

According to the invention there is provided a restrictor device comprising a base having an abutment, a catch mounted on the base to pivot relative thereto and biased to engage said abutment, the catch having a slot therein and there being, at an exit from said slot, locking means which in a normal state thereof block said exit, but can be manually moved to a release state to open said exit.

In one embodiment of use, the base of the restrictor device may be mounted to a one of a window and associated window frame, whilst to the other of the window and associated window frame is mounted a stud plate having an upstanding stud normally received in said slot in the restrictor catch, and retained therein by said locking means closing said exit, thereby allowing the opening of the window by only a small amount. To open the window further, the locking means must be manually moved to the release state thereof, thereby allowing relative movement of the stud out of the slot through said exit.

Preferably with said restrictor device of the invention, the slot extends longitudinally of the catch and has its end remote from the base open.

Desirably the locking means normally closing said open end is in the form of a lever pivotally mounted on the catch and biased to its normal state.

Conveniently the slot defines two arms of the catch at respective opposite sides thereof, and said lever is pivotally mounted at the end of one of said arms, adjacent said open end of the slot. Advantageously the lever has at a side of said one arm remote from said slot a manually actuatable part for pivoting the lever to its release state in which the lever is clear of said open end of the slot.

In a preferred embodiment the lever is biased by an elongated wire spring to its normal state. Conveniently the catch arm to which the lever is pivoted is laminated, and more conveniently the spring is disposed between two plates of the laminated arm. In one embodiment, one end of the wire spring is turned through 90 to engage an edge surface of the lever. At a position spaced from said one end, the wire spring is coiled around a first abutment and preferably at its other end the spring engages a second abutment to effect said bias on the lever. Preferably each of the abutments is a stud fixing together plates of the laminated arm. More preferably the whole of the arm is of laminated form.

In its normal state a surface of the lever facing away from said slot is configurated to engage, in use, with a stud or peg so that the lever is automatically moved thereby to its release state, allowing the stud or peg to enter or re-enter said slot. Desirably the surface is angled relative to the direction of movement of the stud or peg.

The strength of the biasing force on the lever may be such that a young child would find it difficult or impossible to move the lever to its - 4release position in order, in one embodiment of the invention, in use, to open a window, to which the restrictor device is fitted, beyond its restricted amount. Moreover the restrictor device of the invention is designed so that opening of the window beyond its restricted amount requires more manual dexterity and skill than that normally possessed by a young child. To this end a two-handed operation is required, namely release of the lever with one hand together with simultaneous pushing open of the window with the other hand.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a top plan view of a restrictor device of the present invention, Figure 2 is an underneath plan view of the restrictor device of Figure Figure 3 is a view of one side of the restrictor device, Figure 4 is a view of the other side of the restrictor device, Figure 5 is a view like Figure 1, but shows locking means of the restrictor device in an alternative position, Figure 6 is a fragmentary perspective view of a restrictor device of the invention fitted, in use, to a window vertically pivoted in its associated frame, and Figure 7 is an enlarged view of part of the locking means of restrictor device. - 5 -

Although it is envisaged that a restrictor device of the invention could be used in various applications, for example with 'opening panels' other than windows, it will be described hereinafter in relation to its principal use, namely for normally restricting the degree of opening of a window pivoted in an associated window frame.

As shown in Figures 1 to 5, a restrictor device of the invention comprises a base part 10, a catch part 11, and a locking lever 12. The components would generally be in the form of pressings, and, as will be described, the catch part l l is preferably laminated, being formed of an upper plate 13 connected by suitable rivets 14 or the like to a lower plate 15.

Preferably all the components are of stainless steel.

The base part 10 is oi generally conventional form, comprising a rectangular base plate 16 formed with a pair of spaced countersunk screw holes 17 for securing the base part in an channel of a window frame 18 shown in Figure 6. As shown in that Figure, the channel in which the base part 10 is fixed by means of fixing screws through the holes 17 is in the underside of the lower section of the window 19, although normally there would also be a restrictor device similarly at the upper section of the window frame.

Centrally between the screw holes 17 of the base plate 16 is an upstanding cylindrical headed post 20 on which the catch part 11 is pivotally mounted. Midway between the post 20 and one of the screw holes 17 is an upstanding cylindrical abutment post 21. The laminated catch part 11 is pivotally mounted on the post 20 at one of its ends, and at that end, it can be - 6 seen from Figures 1 and 5 that part of the edge surface of each of the plates 13 and 15 is formed with an abutment portion 22 which, when the catch part 11 is in its normal state, engages against the post 21, which thus acts as a stop.

The catch part 11 is biased by a the torsion spring 23 which is coiled around the post 20 beneath the lower plate 15 and has one of its ends extended to hook around the post 21. The other end of the torsion spring 23 extends below the underside of the plate 15 and is then hooked over the side of the catch part so that its free end lies on top of the upper plate 13 as shown in Figures 1 and 5. Accordingly as a consequence of the arrangement of the torsion spring 23, the catch part 11 is biased to its Figure l position in normal use, with the abutment surface at the portion 22 of the catch part 11 engaging against the stop in the form of the post 21.

The laminated catch part l l is of elongated form, having one of its sides 24 straight, with the opposite side 25 diverging relative to the side 24 so that the width of the catch part 11 increases away from its pivoted end.

However formed centrally in catch part 11, namely in both the upper plate 13 and the lower plate 15, is a elongated straight sided slot 26. At its inner end adjacent the post 20, the slot is closed, being of semicircular shape. The other end of the slot 26, is, however, open, in the maimer shown best in Figure 5. Accordingly the slot effectively divides the catch part l l into a first arm 27 which is straight and of constant width, and a second arm 28.

The arm 28 has one of its sides 29 defined by one of the straight sides of the slot, this side 29 extending beyond the end of the first arm 27. At its - 7- end, the straight side 29 is connected via an arcuate surface portion 30 to a semi-circular end portion 31, this portion 31 terminating in a short flat surface portion 32 which meets a similar short flat surface portion 33 at a short curved apex 34. Extending from the surface portion 33 is a longer straight surface portion 35 which meets the longer straight side 25 of the second arm 28.

The locking lever 12, which is shown in detail in Figure 7 and is a flat plate, has a circular opening 37 therethrough, this opening being at a corner of the lever which is externally shaped to match the semi-circular end portion 31 of the second arm 28, so that, as shown in Figures 1, 2 and 5, this part of the locking lever remains concealed from view between the two plates 13 and whether the lever is in its locked or released state. A suitable configurated rivet or pin assembly 38, with an increased diameter part 14a between plates 13 and 15, passes through the opening 37 in the locking lever and also through respective upper and lower aligned holes in the plates 13 and 15 so as to mount pivotally the locking lever 12 to the end of the second arm 28 of the catch part 11.

The corner of the lever through which the opening 37 extends has an external semi-circular surface 38. From one end of the surface 38 extends a straight edge surface 39 of a leg 40 having an opposite shorter straight edge surface 41, which diverges away from surface 39. Next to its end remote from surface 38, the surface 39 has a generally arcuate recess 42 matching the radius of the rivet part 14a, between plates 13 and 15, at the free end of arm 27. In its normal, locked state, the lever is biased so that this recess 42 engages against the rivet part 14a. - 8-

The end of the surface 41 is cut away arcuately to form a larger recess 43, and in its normal state, shown in Figures 1 and 2, the majority of this recess is disposed at the end of the slot 26. From the other end of the surface 38 extends a straight edge surface 43 which leads to a finger part 44 at one side of a recess 45. The recess and finger part together form a location for a user, in use, to place a finger to pivot the lever from its normal Figures 1 and 2 positions, to its unlocked Figure 5 position where it is clear of the slot 26.

The lever 12 is biased to its normal position by a wire spring 46 disposed between the plates 13 and 15 forming arm 28. The spring has one end around a central enlarged diameter part of the rivet 14 of arm 28 nearest post 20, and is coiled around a similar enlarged part of a second rivet of arm 28. Its other end is turned through 90 towards plate 13 and bears against surface 41 to bias the lever to its Figures 1 and 2 position. It will however be appreciated that any other suitable biasing means could be employed.

Moreover the lever could be arranged merely to 'close' the slot in its locked state, without engaging a rivet or other part of arm 27.

Finally with regard to the structure of the restrictor, it can be seen from Figures 1, 4 and 5 that at its junction between the surfaces 25 and 35, the plate 13 is formed with a small inward deformation 47, which acts as a stop for the lever 12 when manually moved in its unlocking direction.

Accordingly in its normal, i.e. locked, state, the lever 12 is biased by spring 46 as shown in Figures 1 and 2 so as to block the open end of slot 26, - 9 - with its recess 42 engaging the rivet part 14a, which thus acts as a stop in the direction of bias.

However as shown in Figure 5, it is possible manually to push the locking lever 12 so that it pivots in the direction of arrow B shown in Figure l, this pushing being achieved, for example, by the use of a forefinger or thumb against the finger 44. This action pivots the locking lever to its released, or open, Figure 5 position, where the leg 40 has now moved away from the open end of the slot 26 so as to lie entirely concealed between the upper and lower plates 13 and 15 of said second arm 28. On release of the force which pivots the locking lever to its Figure 5 position, the force of the spring 46 will automatically return the locking lever to its Figure 1, locked position, so that again the open end of the slot becomes closed. The force of spring 46 will be much stronger than the force of spring 23.

From the above it will thus be appreciated that Figure 1 shows the restrictor device of the invention where the locking lever 12 is in its locked position. Moreover Figure l shows the catch part 11 in its 'open' position relative to the base part 10, whilst movement of the locking lever 12 around its pivot post 20 in the direction of arrow A in Figure 1 will bring the catch part 11 eventually to its closed position where an end surface 48 of the catch part 11 spaced from the abutment portion 22 thereof will engage the abutment post 21 to prevent further pivoting movement of the catch part 11 in the direction of arrow A. As mentioned above, the principal application of the restrictor device of the invention is its use with a window, and such use is shown in Figure 6 - 10 in respect of the window 19 being vertically hung in its frame 18. As shown in Figure 6, the restrictor device is mounted in a channel or groove in the underside of the lower section of the window 19, so that the device appears in Figure 6 substantially as in Figure 2. In conjunction with the restrictor device, there is shown fitted in a channel or groove 49 in the top of the lower section of the window frame, a stud plate 50 which is formed with an upstanding headed stud or peg 51 which is intended to be received within the slot 26 of the restrictor device.

Accordingly during normal operation, the stud 51 is received in the slot 26 with the locking lever 12 in its locked position. This is one of the arrangements shown in Figure 1 where the peg or stud 51 is shown as a circle within the slot 26. The relative positions of the restrictor device and the stud plate in their respective grooves or channels will determine the degree of opening permitted for the window 19 relative to its frame, given that the stud 51 is trapped in the slot 26 in that it cannot move through the open end of the slot by virtue of it abutting the recess 43 ot the locking lever 12 as shown in the one representation in Figure 1.

It is proposed that the spring 46 which biases the locking lever 12 to its closed position is relatively strong, and thus it may be that the biasing force alone will be sufficient to prevent a young child moving the locking lever 12 form its locked to its unlocked position, i.e. from the position shown in Figure 1 to that shown in Figure 5. However irrespective of the force of the spring 46, it will be appreciated that in order to disengage the stud 53 from the slot 26, and thus enable the window to be opened beyond its restricted amount, it is necessary for a two-handed action to take place, - 11 namely for the locking lever 12 to be moved to its open position by the use of one hand, and the window 19 itself to be moved outwardly, whilst the locking lever is held open, by the use of the other hand. Thus it is believed that a child-proof restrictor device is provided.

From the above it will be understood that during normal use a degree of opening of the window is restricted by the engagement of the stud 51 in the 'closed' slot 26. If it is required to open the window to a greater degree, the action outlined above is required, namely a pivoting of the locking lever manually, by the use of one hand, in the direction of arrow B shown in Figure l, until the leg 40 is wholly clear of the slot. With the locking lever 12 being held in its open state, the user's other hand then pushes the window 19 to open further. This causes the stud 51 to move to the end of the slot and then out of it, so that if the locking lever 12 is then released, the stud will be at the second position shown in Figure l, and thus clear of the restrictor device. The window can then be fully opened in that the restrictor device has no control over its further movement in the opening direction.

Upon closing the window thereafter, the biasing force of the spring 23 ensures that the catch part 11 is in its open position, as shown in Figure 1, when its end remote from the base part 10 approaches the stud 53.

Accordingly as the window continues to be closed, the stud 51 is engaged by the surface 39, shown in Figure 6, so that the relationship between the locking lever 12 and the stud 51 is initially as shown schematically at the lower part of Figure 1 with the stud being also possibly partly engaged by the arcuate surface 31 as well as the straight surface 39. Continued closing of the window from this point, initially causes slight pivoting movement of the - 12 locking lever 12 in the direction of arrow B in Figure 1, but more significantly, movement of the stud 51 along surface 39 causes the catch part 11 to move bodily about the arrow A in Figure 1 until the stud reaches the end of the surface 39, whereupon continued movement of the window towards its closed position causes the stud now to force the locking lever 12 about its pivot in the direction of the arrow B. so that the stud can pass beyond the leg 40 of the locking lever and into the slot 26, so that it is then positioned as for the upper representation of the stud 51 shown in Figure 1.

The window can then be fully closed, or moved to any position between its fully closed and restricted opened state with the stud now being retained within slot 26 until, and unless, the locking lever is again moved to its released position in order to allow movement of the stud out of the slot 26.

Although Figure 6 shows the use of a restrictor device of the invention with a window mounted to its frame about a vertical pivot, it will be understood that the restrictor is suitable for application to windows having opening configurations of side hung, top hung, projecting side hung/top hung, horizontal/vertical pivot with opening in or out format. The device is suitable for use with Eurogroove or surface mounting. The restrictor device can be supplied either right or left handed, as required. The height of the stud 51 of the stud plate 50 can be supplied of any appropriate height, as is well known with conventional restrictor devices.

Accordingly an effective and convenient child-proof improved restrictor device is provided, so that whilst safe limited opening of the window for ventilation purposes is possible, opening beyond the restricted debris can only be carried out as a two-handed operation, including - 13 movement of a locking member against a relatively strong spring biasing force. However for a normal user, the locking lever is releasable in a straight forward manner, without requiring the use of a special key, with the attendant possibility that this can become mislaid or lost. - 14

Claims

Claims 1. A restrictor device comprising a base having an abutment, a

catch mounted on the base to pivot relative thereto and biased to engage said abutment, the catch having a slot therein and there being, at an exit from said slot, locking means which in a normal state thereof block said exit, but can be manually moved to a release state to open said exit.
2. A device as claimed in Claim 1, wherein the slot extends longitudinally of the catch and has its end remote from the base open.
3. A device as claimed in Claim 2, wherein the locking means normally closing said open end is in the form of a lever pivotally mounted on the catch and biased to its normal state.
4. A device as claimed in Claim 3, wherein the slot defines two arms of the catch at respective opposite sides thereof, and said lever is pivotally mounted at the end of one of said arms, adjacent said open end of the slot.
5. A device as claimed in Claim 4, wherein the lever has at a side of said one arm remote from said slot a manually actuatable part for pivoting the lever to its release state in which the lever is clear of said open end of the slot.
6. A device as claimed in Claim 3, wherein the lever is biased by an elongated wire spring to its normal state. -
7. A device as claimed in Claim 4, wherein the lever is biased by an elongated wire spring to its normal state and the catch arm to which the lever is pivoted is laminated.
8. A device as claimed in Claim 7, wherein the spring is disposed between two plates of the laminated arm.
9. A device as claimed in Claim 6, wherein one end of the wire spring is turned through 90 to engage an edge surface of the lever.
10. A device as claimed in Claim 9, wherein at a position spaced from said one end, the wire spring is coiled around a first abutment.
11. A device as claimed in Claim 10, wherein at its other end the spring engages a second abutment to effect said bias on the lever.
12. A device as claimed in Claim 7, wherein one end of the wire spring is turned through 90 to engage an edge surface of the lever.
13. A device as claimed in Claim 12, wherein at a position spaced from said one end, the wire spring is coiled around a first abutment.
14. A device as claimed in Claim 13, wherein at its other end the spring engages a second abutment to effect said bias on the lever.
15. A device as claimed in Claim 14, wherein each of the abutments is a stud fixing together plates of the laminated arm. - 16
16. A device as claimed in any one of Claims 7, 8 and 12 to 15, wherein the whole of the arm is of laminated form.
17. A device as claimed in any one of Claims 3 to 16, wherein in its normal state a surface of the lever facing away from said slot is configured to engage, in use, with a stud or peg so that the lever is automatically moved thereby to its release state, allowing the stud or peg to enter or re-enter the slot.
18. A device as claimed in Claim 17, wherein the surface is angled relative to the direction of movement of the stud or peg.
19. A window fitted with a restrictor device as claimed in any one or the preceding Claims.
20. A restrictor device substantially as hereinbefore described, with reference to, and as shown in Figures 1 to 5 and 7 of the accompanying drawings.
21. A window fitted with a restrictor device substantially as hereinbefore described, with reference to, and as shown in Figure 6 of the accompanying drawings.