AU645994B2

AU645994B2 - Sash window brake

Info

Publication number: AU645994B2
Application number: AU64511/90A
Authority: AU
Inventors: Michael Brian Alchin
Original assignee: Alchin and Long Group Pty Ltd
Current assignee: Alchin and Long Group Pty Ltd
Priority date: 1989-11-13
Filing date: 1990-10-11
Publication date: 1994-02-03
Anticipated expiration: 2010-10-11
Also published as: AU6451190A

Description

45994 FORM 10 S F Ref: 112677 FORM 10 COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFi~-TION

(ORIGINAL)

FOR OFFICE USE: Class Int. Class Application Number: PJ7351 Lodged: 13 November 1989 Accepted: Published: Priority: Related Art: Name and Address of Applicant: Alchin Long Group Pty Limited Lot 9 Redfern Street Wetherill Park New South Wales 2164

*.AUSTRALIA

Actual Inventor: Michael Brian Alchin Address for Service: Spruson Ferguson, Patent Attorneys, Level 33 St Martins Tower, 31 Market Street, Sydney, New South Wales, 2000, Australia Complete Specification for the invention entitled: Sash Window Brake The following statement is a full description of this invention, including the best method of performing it known to me/us S0o 778 1 11/ 10/90 5815/2

ABSTRACT

A brake is provided for sash windows. The brake comprises a frame having symmetrical and opposed arms, each arm comprising an outwardly facing brake pad area and inwardly, downwardly facing ramps. A wedge member is slidably received between the arms. The ramp and wedges cooperate to spread the arms as the wedge member is withdrawn from the frame.

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,to a e rhk/0150E 1A SASH WINDOW BRAKE FIELD OF THE INVENTION The present invention relates to sash windows and more particularly to a brake system for sash windows.

BACKGROUND ART Sash windows consists of a window jamb including vertical members which slidably receive a window panel usually including a glass sheet. It has been the practice to provide a balance system for the window so that it may be retained in a raised position. However, it is known that balance systems for sash windows are not always reliable, are complex and generally expensive.

OBJECT OF THE INVENTION It is therefore the object of the present invention to substantially ameliorate the disadvantages of the prior art and provide an alternative to sash window balances.

SUMMARY OF THE INVENTION •There is disclosed herein a window brake comprising: a frame having symmetrical and opposed arms; the arms each comprising an outwardly facing brake pad area and 20 inwardly and downwardly facing ramps, wherein both &rms are commonly connected to a base portion; a wedge member slidably received between the arms and comprising opposed upwardly facing wedge means; and side panels which orient and locate the wedge member with respect to the frame; whereby the ramps and wedge means cooperate to spread the arms as the wedge member is withdrawn from the frame.

BRIEF DESCRIPTION OF THE DRAWINGS S\ A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: Figure 1 is a perspective view of a sash window brake.

Figure 2 is a front elevation of a main frame.

Figure 3 is a side elevation of the main frame of Figure 2.

Figure 4 is a bottom plan view of the main frame depicted in Figures 2 and 3.

Figure 5 is a front elevation of a wedge member.

Figure 6 is a side elevation of the wedge member depicted in Figure Figure 7 is a bottom plan view of the wedge member illustrated in ;i 1 Figures 5 and 6.

/O0150E -2- BEST MODE AND OTHER EMBODIMENTS OF THE PRESENT INVENTION As shown in Figure 1, a window brake according to the present invention comprises a main frame 11 and a wedge member 12. As shown in more detail in Figures 2, 3 and 4, the main frame 11 includes generally symmetrical opposing arms 13 connected by a base 14. The upper portion of each arm terminates in-a brake pad area 15 which may be enlarged if required. Each arm 13"also includes an inward and downwardly facing wedgp portion 16. Protruding upwardly from the base 14 there is a small stub 17.

The wedge member 12 is slidabiy received within the main frame 11.

As shown more clearly in Figures 5, 6 and 7, the wedge member 12 preferably includes opposed upwardly facing wedges or ramps 18 which slidably contact the downwardly facing wedges 16 of the main frame 11. The wedge member 12 further includes side panels 19 which orient and locate the wedge member with respect to the main frame. The top portion of the wedge member comprises a slot or other retention means 20 for retaining the lower end of i* the balance spring of the window apparatus, as will be explained in more detail. The bottom portion of the wedge member 12 has formed therein a recess 21, which when the wedge member is received by the main frame, is generally aligned with the protruding stub 17 of the main frame.

In the preferred embodiment, a resilient spring 22 or other resilient bias is located by the protruding stub 17 and extends into the recess of 21 of the wedge member. This resilient spring 22 exerts a compressive force which tends to drive the wedge member 12 upward, thereby biasing the arms 13 of the main frame 11 apart from one another.

As shown more clearly in Figures 2, 3 and 4, the main frame further includes a slot or aperture 23 perpendicular to the main axis 24 of the main frame. To use the brake, a small metal tab is affixed to the bottom portion of a sliding sash window. The tab, which may have barbed projections for better retaining the main frame is inserted into the slot 23, thereby affixing the main frame 11 to the bottom portion of the sash.

It will be understood that the jamb Frame which receives the sash includes a track or groove in which the sash is vertically slidable. An elongated spring is suspended within the groove or track from the top of rhk/0150E -3said track. The bottom of the elongated spring attaches to the retaining slot 20 of the wedge member 12. The tension in this elongated spring aids in retaining the sash panel in a desired position relative to the jamb frame. The elongated spring is in a condition of maximum tension when the sash is fully lowered. The tension exerted by the elongated spring directs the wedge member upwardly, thus tending to separate the arms 13 of the main frame 11, which in turn creates a frictional engagement with the groove or track, thus tending to maintain the sash in a fixed position. In the raised position the elongated spring is in a condition of minimum tension whereupon the upwardly directed force on the wedge is at a minimum. It is for this purpose that the coil spring 22 is provided. The coil spring 22 tends to drive the wedge member 12 upwardly, creating a braking action, should the tensile force exerted by the elongated spring be insufficient.

It will be appreciated that the brake mechanism disclosed by the present invention is, in a sense, self sizing. By this it is meant that the braking force exerted by the opposed arms 13 against the groove or track is proportional to the tension in the elongated spring which supports the sash. Thus, in a large window where a large spring balances a large sash, a larger tensile force operates on the wedge member 12, which in turn 20 creates a larger braking force by the opposed arms 13. In this way, one a.

size brake may be used in a number of different window sizes and will exert a suitable braking force in each different window size.

Glass filled "NYLON 66" is considered a suitable material for the construction of both the main frame 11 and the wedge member 12.

NWhile the present invention has been described with reference to particular materials and details of construction, these will be understood as having been provided by way of example and not as limitations to the ss on scope or spirit of the invention.

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Claims

2. The brake of claim 1, wherein a resilient spring is interposed between the wedge member and base portion.
3. The brake of claim 2, wherein a first end of the spring is retained by a protruding stub extending from the base and a second end of the spring is retained with a recess formed in the wedge member.
4. The brake of any one of claims 1-3 wherein the brake pad area comprises an enlarged portion on a tip of each arm. The brake of any one of claims 1-4 wherein the base has an 20 aperture formed therein whereby it may be affixed to a bottom portion of a sash.
6. A window brake substantially as hereinbefore described with reference to the drawings. DATED this THIRTIETH day of NOVEMBER 1993 Alchin Long Group Pty Limited o o Patent Attorneys for the Applicant SPRUSON FERGUSON RLF/0150E