GB2142365A - Roller assembly for a sliding closure - Google Patents

Abstract

A roller assembly for a sliding closure eg a patio door, comprises a casing 14 in which is mounted a carriage 18 housing two wheels 20. Screw adjustment moves the carriage vertically with respect to the casing by means of a pin-and- slot connection. <IMAGE>

Description

SPECIFICATION Roller assembly for a sliding closure This invention relates to a roller assembly for a sliding closure, such as a Patio Door.

Traditionally roller assemblies of this type are mounted within the bottom channel section of the perimeter frame of the sliding panel of a Patio Door.

The disadvantages of conventional roller assemblies are: a) If roller damage occurs, the whole closure must be dismantled in order to replace parts.

b) In a marine or heavy chemically laden atmospheric environment, excessive corrosion can occur causing collapse or inoperation of the closure.

c) The overall height of the roller controls the perimeter frame dimensions of the closure since it is housed by the bottom channel. This height is more than the closure designer requires for the bottom channel to fulfill its function as a frame member and hence increases the material costs.

d) Excessive side movement of the sliding closure can occur because of cummulative tolerance clearances in the mechanisms and linkages. This movement can reduce the weather performance of the closure quite drastically and allow "bogeying" of the two wheels of a tandem roller assembly making the closure difficult to operate. It is the object of this invention to overcome these disadvantages.

Accordingly, the present invention provides a roller assembly for a sliding closure which comprises a casing adapted for securement to the sliding closure, a carriage mounted in the casing for movement relative thereto for height adjustment purposes, at least one wheel complete with ball race rotatably supported by the carriage, the axle of the or each wheel being a snap fit in the carriage, a yoke which is connected to the carriage by means of a snap-in axle pin, an adjusting screw which connects to both yoke and casing for adjustment purposes.

Preferably, adjustment is achieved by turn- ing the said adjusting screw which is mated to a nut or screwed block mounted within the yoke which in turn is connected to the carriage which slides within the casing. This essentially horizontal screw adjustment is converted into vertical adjustment, necessary for raising or lowering of the said closure, by guide pins slidably engaging in slots in the sides of the casing. For a roller with two wheels (or tandem roller), one guide pin is necessary, which rotatably connects carriage to yoke and slides in two inclined slots in the sides of the casing, For a roller with one wheel the same components making up the tandem roller are used except the wheel nearest to the adjusting screw is replaced with a second guide pin which slides in two horizontal slots in the sides of the casing.

Preferably, each wheel has a concave or "V" shaped peripheral surface in cross section for engagement on a track on which the closure runs. To assist this engagement and retain good alignment the carriage may be provided with a pair of flanges which extend below the peripheral edge of the roller. These flanges also help prevent side movement of the closure and "bogeying" of tandem rollers.

A brush or pad of bristles may also be provided (Preferably mounted on the underside of the carriage) to effect cleaning of the said track.

Advantageously, all component parts of the roller assembly are made from corrosion resistant materials, except the ball race bearing within each wheel which is grease filled and sealed against water penetration.

The invention will now be further described by way of example only with reference to the accompanying drawings, in which: Figure 1 is a perspective view, with parts cut away, of a roller assembly according to the invention, secured to a sliding closure; Figure 2 is a side view of the roller assembly; Figure 3 is a similar view to Fig. 2 but showing the roller assembly in section; Figure 4 is an underneath plan view of the roller assembly; and Figure 5 is a sectional side view of one component of the roller assembly Referring first to Fig. 1, there is shown therein a sliding closure (in this embodiment, a patio door) having an outer framework 10 constructed from H-section metal or plastic extrusions. The extrusions define an inwardlydirected channel 11 in the framework, in which a glazing construction (not illustrated) is received.A pair of roller assemblies 1 2 are secured to the bottom of the framework 10 so as to permit the closure to slide along a fixed track 1 3. The two roller assemblies are fitted adjacent the ends of the closure respectively: although only one of the assemblies 1 2 is actually shown in Fig. 1, it is to be understood that the other assembly is identical thereto.

Each roller assembly 1 2 comprises generally a casing 14 which is open at its front and its bottom (in Fig. 1 the casing is shown partly cut away for the sake of convenience.) The top and rear sides of the casing 14 have respective threaded openings 1 5 and 1 6 formed therein by means of which the whole assembly is secured to the closure. More particularly, the opening 1 5 receives a bolt 1 7 which is passed through a plain hole in the web of the extrusion which forms the bottom of the framework 10, while the opening 1 6 receives a similar bolt 1 8 which is passed through a slot in the web of the extrusion which defines an end of the framework.

Mounted within the casing 14 is a carriage 1 9 which rotatably carries a pair of wheels 20. Each of the wheels 20 has an outer periphery which is concave or ''V" shaped in cross-section, i.e. configurated for engagement with the track 1 3. The carriage 1 9 includes a pair of side pieces 21 which extend downwardly on either side of the track and which terminate at a level below the upper surface of the latter. This arrangement improves closure engagement on track, helps prevent side movement of closure and "bogeying" of tandem rollers. These flanges also prevent the closure jumping off the track in the event of the closure being struck from the side.

Referring now also to Figs. 2 to 5, the carriage 1 9 also includes a bridging piece 22 which integrally interconnects the side pieces 21. The wheels 20 are accommodated between the side pieces 21, and (as may be seen to advantage in Fig. 4) the front and rear surfaces of the bridging piece 22 may be shaped so as to conform to the profile peripheries of the wheels. Each wheel 20 has an axle 23 on which it is rotatably mounted by means of an integral bearing, the ends of the axle 23 being received as a snap-fit in a pair of aligned clip portions 24 provided in the side pieces 21 respectively and at a respective end of the carriage 1 9. To facilitate its removal from the respective clip portions, each axle has dimples 25 in its end surfaces to provide purchase for a suitable tool.

A further pair of aligned clip portions 26 are provided in the side pieces 21 at the top of the carriage 19, and receive a guide pin 27 as a snap-fit therein. Ends of the guide pin are slidably engaged in respective inclined slots 28 formed in the sides of the casing 14, only one of these slots being visible in Fig. 2. A further, generally horizontal slot 29 is also formed in each side of the casing and slidably receives the aforementioned second guide pin in place of the wheel 20 nearest to adjusting screw 35.

(This only applies to the single wheel roller assembly, not shown) This arrangement of guide pins and slot converts the essentially horizontal adjustment of the adjusting screw to vertical adjustment of the closure.

Referring more particularly to Fig. 3, the adjustment device comprises a yoke 30 disposed within the casing 14 and coupled at one end thereof to the carriage 1 9 by means of the aforementioned guide pin 27. At its opposite end, the yoke is broadened out into a loop and has an apertured web 31 to which a nut 32 is secured. A bolt 33 is threadedly engaged with the nut 32 and passes through an opening 34 in the rear of the casing 14 such that its head 35 is disposed externally of the latter. A compression spring 36 acts between the casing and the web 31 to ensure the carriage wheels and yoke are held inside the casing, necessary to facilitate closure engagement on track.When the bolt 33 is turned, the nut 32 is drawn along the bolt and carries with it the yoke 30 hence the carriage 19, so that the attitude of the carriage relative to the casing may be suitably set by adjustment of the bolt 33. Access to the bolt head 35 for the purpose of such adjustment can easily be gained from the end of the closure through the aforementioned slot in the framework 10.

By adjusting both of the roller assemblies 1 2 concurrently in the above-described manner, the height of the closure relative to a sill of the frame in which it is mounted, can be performed. On the other hand, adjustment of one or other of the assemblies alone can be utilised to square up the closure within the frame.

The roller assembly described above has the advantage that it is in the form of a selfcontained unit and can therefore be readily secured to the closure. In addition, in the event that either of the wheels 20 should become damaged or worn, it/they can readily be removed from the assembly (by virtue of the snap-engagement of its axle with the clip portions 24) without the need to remove the remainder of the assembly from the closure.

Moreover, if the major compounds of the assembly are made of suitable materials, the need to replace these components due to corrosion will be virtually eliminated. In this regard, the casing 14, the wheels 20 and the yoke 30 may be made of stainless steel (preferably incorporating titanium), while the carriage 1 9 may be made of a suitably strong plastics material, such as acetal. utilizing its resilience for snap in application and its good wear charictaristics.

The roller assembly described above is suitable for use where heavy loadings will be experienced, and therefore two rollers 20 are provided. In situations where only light loadings will occur, it is possible to omit the rearmost of the two wheels 20 and to snapengage a guide element similar to the pin 27 in the respective clip portions 24 so that this element slidably engages the slots 29.

If desired, a pad of bristles 37 or the like may be secured to the underside of the bridging piece 22 of the carriage 1 9 to wipe along the track 1 3 and thereby clean the latter as sliding movement of the closure is effected, for example in the manner depicted in Fig. 5.

The roller, because of the careful attention to size and placement of components allows more adjustment and a smaller overall closed height than conventional rollers.

Claims (10)

1. A roller assembly for a sliding closure such as a Paio Door, the assembly comprising one or two wheels rotatably supported in a high strength, self lubricating plastic carriage on integral snap-in axle pins, the carriage being connected to a height adjusting yoke linkage with a further snap-in axle pin, the said yoke and wheel axle pins connected and housed within a casing suitably designed for fitment to a sliding closure.

2. A roller assembly as claimed in Claim 1 wherein either one or two wheels with integral axle pins, depending on the load bearing requirements, are press fitted into mating retaining slots within the carriage, using the resiliant properties of the plastic moulded carriage to retain them.

3. A roller assembly as claimed in Claims 1 and 2 wherein defective or damaged wheels can be removed from and replaced into the same carriage simply and quickly without dismantling the whole sliding closure.

4. A roller assembly as claimed in Claim 1 wherein the self lubricating properties of the carriage material enable closer contact between moving parts without increasing wear rates and hence eliminating excessive side movement of ths sliding closure away from its weather sealing face.

5. A roller assembly as claimed in Claim 1 wherein the same component parts can be used to assemble either a roller assembly with one wheel for normal load conditions or a roller assembly with two wheels for heavy duty load conditions, the assembly with one wheel utilising the 4 slot cut outs in the casing and the assembly with two wheels utilising the two angled slots to facilitate height adjustment.

6. A roller assembly as claimed in Claim 1, 2, 3 & 5 wherein a brush or pad of bristles is incorporated with the carriage, adjacent to the wheel/s to facilitate the cleaning of the track on which the sliding closure slides, thus removing sand, grit and other abrasive elements prevalent on building sites and which often cause irreparable damage to the roller and/or track.

7. A roller assembly as claimed in Claim 1 wherein the careful attention to size and placement of component parts allows more height adjustment and a smaller overall closed height than conventional rollers.

8. A roller assembly as claimed in Claim 1 wherein the careful selection of component part materials virtually eliminate corrosion problems, the only corrosion susceptable items being the steel balls within the wheel bearing which are sealed in grease, but in the event of grease loss and subsequent corrosion attack, wheels can be quickly and easily replaced as described under claim 3.

9. A roller assembly for a sliding closure substantially as herein before described with reference to Figs. 1-5 on the accompanying drawings.

10. A sliding closure incorporating at least one roller assembly as claimed in any one of claims 1-9.