GB2163801A - Sliding patio door frame - Google Patents

Abstract

A sliding patio door frame comprising a frame (4) having at least one sliding frame member (6) and at least one fixed frame member (7), at least the sliding frame member (6) having a bottom sill rail (8) which is provided with a cover member (26), the cover member (26) extending longitudinally inside the bottom sill rail (8), the cover member (26) being held in position by being a push fit to the sliding frame member (6), and the cover member (26) being effective to substantially seal an inner part (16) of the bottom sill rail (8) from an outer part (18) of the bottom sill rail (8). Thus the inner part of the sill rail is shielded from the relatively cold air which blows along the inside of the frames around the rollers. <IMAGE>

Description

SPECIFICATION Sliding patio door frame This invention relates to a sliding patio door frame, and to a sliding patio door when provided with the frame.

Sliding patio doors are well known. They are usually double glazed with a view to avoiding loss of heat from inside a room to outside.

The double glazing also stops much of the condensation that previously occurred in winter due to hot air inside the room engaging the relatively cold surface of a single sheet of glass, the said single sheet of glass having its outside surface in contact with the cold outside air. Some condensation may still occur, even with double glazing, on the metallic parts of the frame of the sliding patio doors. This is because the metal frame, which is usually made of an aluminium alloy, has an inside part in contact with the relatively warm interior of the room and an outside part in contact with the relatively cold outside air.

In an attempt to combat condensation on the metal frame of the sliding patio doors, there have been recently been introduced so-called thermal break sliding patio door frames. These frames are such that they are divided into an inner part and an outer part which are separated by a thermally insulating material which may be, for example, thermally insulating unplasticised polyvinyl chloride. The thermally insulating material is usually provided as a liquid in desired channels of the frame and is then cured in situ. The metal of the bottoms of the channels is cut away, either before or after the provision of the thermally insulating material in the channels.The cured thermally insulating material then separates the inner and outer parts of the frame and so substantially hinders the transfer of cold from the outer part of the frame which will be in contact with the outside air to the inner part of the frame which will be in contact with the hotter air in the room. Several methods are known of cutting and filling the channels and, since these methods are well known, they will not be described further.

Condensation can still exist on the thermally insulated frames due to the fact that the frames are hollow and various portions of the frames are not closed to the air. Thus, relatively cold outside air can be blown along the inside of the frames and it may engage the inner part of the frame. Thus, although the inner and outer parts of the frame are physically separated from each other by the thermally insulating material, the inner part of the frame is still subjected to the relatively cold air and condensation still occurs. Attempts have been made to prevent this condensation occurring by blocking parts of the frames.

More specifically, a major source of frame condensation is the bottom horizontal sill rail of the sliding door. This sill rail has to be open along its lowermost edge so that the rollers on which the sliding door slides can project downwardly beyond the sill rail. The known attempts to block the bottom sill rail have not been totally acceptable because difficulties arise in production. In one known frame, the bottom sill rail is filled with a foam material which then has to be dug out to form a channel in which the rollers of the sliding door of the sliding patio door frame can run in. This is a time consuming operation and is also wasteful of material. In another known frame, a cover member is employed and which is fixed into the bottom sill rail before the rollers of the sliding patio doors are fitted in position.The cover member saves on material as compared with the foam idea, but the cover member has to be provided with slits to allow the rollers to project through the cover member. Air can thus pass through the slits and contact the inner part of the sill rail and cause the unwanted condensation.

It is an aim of the present invention to provide a sliding patio door frame in which the above problems associated with the bottom sill rail are obviated or reduced.

Accordingly, this invention provides a sliding patio door frame comprising a frame having at least one sliding frame member and at least one fixed frame member, at least the sliding frame member having a bottom sill rail which is provided with a cover member, the cover member extending longitudinally inside the bottom sill rail, the cover member being held in position by being a push fit to the sliding frame member, and the cover member being effective to substantially seal an inner part of the bottom sill rail from an outer part of the bottom sill rail.

Because the cover member is a push fit to the sliding frame member, it is easily fitted and the use of fixing screws is avoided. This in turn can save on assembly time.

Preferably, the cover member has upper and lower lips for clipping into upper and lower grooves formed in the sliding frame member.

A supplementary cover member which extends underneath the bottom sill rail and up along an inner face of the bottom sill rail may be provided.

The supplementary cover member may be held in position by being screwed to the bottom sill rail.

The bottom sill rail of the fixed frame member may also have a cover member but this will usually not be necessary. This cover member may be provided with a brush sealing member.

Other parts of the sliding patio door frame may also have cover members for substantially isolating the inner and outer parts of the frame, whereby relatively cold atmospheric air cannot engage the inner parts of the frame. These other parts may be, for example, upright frame members.

The cover members may be made of an extruded plastics material, for example unplasticised polyvinyl chloride. Other materials such for example as rubber may be employed if desired.

This invention also provides a sliding patio door when provided with the sliding patio door frame.

The sliding patio door will usually be double glazed.

An embodiment of the invention will now be described solely by way of example and with reference to the accompanying drawing which is a vertical section through the sliding part of a sliding patio door.

Referring to the drawing, there is shown a sliding patio door 2. The patio door 2 comprises a patio door frame 4 having a sliding frame member 6 and a fixed frame member 7. As shown in the drawing, the lower part of the sliding frame member 6 comprises a horizontally extending bottom sill rail 8 which is hollow as shown. Supported on an upper portion of the sill rail 8 is a double glazing sealed unit comprising two panes of glass 10, 12 which are spaced apart by a spacer member 14. The sheet of glass 10 will be inside a room and the sheet of glass 12 will be exposed to the outside air.

The hollow sill rail 8 is open along its lowermost edge 9 as shown. The sill rail 8 has an inner part 16 in the room and an outer part 18 which is exposed to the outside air. In order to prevent cold air on the outer part 18 being transmitted to the inner part 16, the sill rail 8 is separated into the inner part 16 and the outer part 18 by a thermally insulating member 20 formed of unplasticised polyvinyl chloride. The lower part of the thermally insulating member 20 will initially rest on a metallic part of the frame (not shown) bridging the inner and outer parts 16, 18.

The thermally insulating member 20 will first be poured into the channel and then it will be cured in situ. When the thermally insulating member has cured, it will be effective to hold the inner part 16 and the outer part 18 together and so, at this point in time, the metal member bridging the parts 16, 18 can be cut away in a known manner to effectively thermally isolate the inner part 16 from the outer part 18.

Because the sill rail 8 is open along its lowermost edge 9 and because the sill rail 8 is a hollow member as can be seen from the drawing, it will be apparent that cold air from the outside can be blown through the sill rail 8, especially in stormy winter conditions.

It is thus possible for the cold outside air to touch the inside surface 22 of the inner part 16 and thus cause the inner part 16 to be colder than the air in the room. This will in turn cause condensation to form on the outside surface 24 of the inner part 16.

In order to substantially reduce or prevent the cold air from blowing along the inside of the sill rail 8 and adversely cooling the inner part 16, a cover member 26 is provided. The cover member 26 comprises a pair of upper and lower lips 28,30 respectively. These lips 28,30 clip in to extruded grooves 32, 34 respectively formed in the inner part 16. The lower lip 30 helps to define a channel 33 formed in the cover member 26, the channel 33 receiving a complementary male portion 35 formed as part of the inner part 16.

A roller assembly 36 is also positioned inside the sill rail 8 and it is secured in position against an extruded part 38 of the sill rail 8 by screws (not shown) which pass into a screw channel 40.

As shown in the drawing, the cover member 26 can be pushed to clip or slide into the channels 32, 34. The cover member 26 is thus a push fit to the inner part 16 and it is not necessary to employ fixing screws. With the cover member 26 held in position as illustrated, there is no necessity to aperturethe cover member 26 to allow the roller assembly 36, or at least the rollers 42 thereof, to protrude through the cover 26, as occurs with a known prior design, whereby cold air could pass through the cover member 26 and adversely cool the inner part 16.

If desired, the ends of the cover member 26 may be arranged to extend into and across the upright frame members.

As can be seen from the drawing, the roller members 42 run on a bead 44 which is upstanding from the fixed frame 7. Since the roller members 42 are usually made of stainless steel and since the bead 44 is usually made of extruded aluminium, the bead 44 is advantageously covered with a stainless steel cover 47 in order to stop the roller members 42 wearing the bead 44.

The fixed frame 7 has an inner part 46 which is inside the room and an outer part 48 which is outside the room. The inner part 46 and the outer part 48 are separated by a thermally insulating member 50 which can be provided exactly in the same manner as the thermally insulating member 20.

The inner part 46 is provided with a rubber threshold member 52 which snaps into an appropriately grooved recess 54 as shown and which may be trod on when the sliding frame member 6 is open.

A pair of brush seals 56,58 brush against the sliding frame member 6 to stop the ingress of air in the direction of the arrow 60. Air passing in the direction of the arrow 60 cannot get inside the fixed frame member 7 due to a plastics member 62 which is formed with the brush seal 58. The plastics member 62 may be made of unplasticised polyvinyl chloride and it is provided with a slot 64 for receiving a flange 66 whereby the member 62 can be pushed over the flange 66 and held in position.

A cover member 68 is provided in the position shown to stop cold air in the vicinity of the arrow 60 from passing over the top of the thermally insulating member 50 and contacting the frame parts 70,72,74 and possibly causing unwanted condensation on the fixed frame part 7. As can be seen from the drawing, the fixed frame part 7 is located on a wooden horizontally extending sill 76.

The fixed frame part 7 is provided with a sealed double glazed unit (not shown) in a known manner, and with a brush seal 80.

In order to help prevent cold air in the vicinity of the arrow 60 touching the male portion 35 and adjacent parts, a supplementary cover 81 is provided. The cover 81 is held in position by screws, one of which is shown as screw 83.

Referring now to the top portion of the drawing, it will be seen that the sliding frame member 6 has a top sill 82. The top sill 82 is in two parts 84,86 as shown. The two parts 84,86 are separated by a thermally insulating member 88 which is like the member 20.

The patio door 2 has an upper section which is provided on the outside with three outwardly projecting elongate flanges 90 which give this part of the patio door 2 a pleasing louvred appearance.

On the inner part of the upper section, opposite the flanges 90, a hit and miss night vent 92 is provided. The night vent 92 is made of a plastics material such as unplasticised polyvinyl chloride and it is shaped as shown. It slides to and fro in the complementary shaped recess 94 to open and shut ventilation apertures (not shown) in a wall 96 of the recess 94.

In order to help prevent unwanted condensation, a thermally insulating member 98, two unplasticised polyvinyl chloride cold-resisting bridges 99, 100 and a head filler section 102 are provided. The section 102 has a lip 103 which locates in a complementary groove 104. The section 102 also has a clip portion 106 which can be sprung onto a flange 108 as shown.

It is to be appreciated that the embodiment of the invention described above has been given by way of example only and that modifications may be effected. Thus, the illustrated cross sectional shape of the cover member 26 may be varied. Also, the supplementary cover 81 can be omitted. Further, the cover 26 could be provided with recesses which would receive protruding members on the inner part 16, whereby the cover 26 would still be a push fit to the inner part 16. Also, larger patio doors can be produced if desired with, for example, two sliding doors or two fixed doors.

Claims (7)

1. A sliding patio door frame comprising a frame having at least one sliding frame member and at least one fixed frame member, at least the sliding frame member having a bottom sill rail which is provided with a cover member, the cover member extending longitudinally inside the bottom sill rail, the cover member being held in position by being a push fit to the sliding frame member, and the cover member being effective to substantially seal an inner part of the bottom sill rail from an outer part of the bottom sill rail.

2. A sliding patio door frame according to claim 1 in which the cover member has upper and lower lips for clipping into upper and lower grooves formed in the sliding frame member.

3. A sliding patio door frame according to claim 1 or claim 2 and including a supplementary cover member which extends underneath the bottom sill rail and up along an inner face of the bottom sill rail.

4. A sliding patio door frame according to claim 3 in which the supplementary cover member is held in position by being screwed to the bottom sill rail.

5. A sliding patio door frame according to any one of the preceding claims in which the cover member is made of an extruded plastics material.

6. A sliding patio door frame substantially as herein described with reference to the accompanying drawing.

7. A sliding patio door when provided with a sliding patio door frame as claimed in any one of the preceding claims.