GB2304377A - Slideaway door gear - Google Patents

Abstract

In a slideaway door gear, preferably for an up and over garage door, comprising a cam surface for guiding a first door part; an arm 54 pivotably securable at a first location to a second door part 20 and at a second location to an arm pivot 27 fixed relative to the arm; and a resilient member 24b acting between the arm and a third location 23 to assist movement of the door, each end of the resilient member is securable in a plurality of positions to the arm and at the third location. Preferably the resilient member comprises two tension or compression springs acting in parallel and secured at each end to a common anchor, each anchor being locatable in a selected one of a plurality of holes in an associated bracket. The construction provides for adjustment of the spring tensioning, thereby reducing the number of different types of spring needed to support different types of door.

Description

A DOOR GEAR This invention relates to a so-called slideaway or fully retractible door gear (referred herein as a slideaway door gear), in particular but not exclusively intended to support a garage door and guide it between its open and closed positions.

Slideaway door gears pg se are known in the garage door art for lifting garage doors.

Usually it requires a pair of discrete door gears, fixed at either side of a garage door opening, to lift a garage door successfully. A typical slideaway door gear installation includes a pair of parallel, horizontally extending tracks secured at the top of the surround for a garage door and extending rearwardly into the garage interior. An upper portion of a garage door is moveably supported on the tracks, which are spaced from one another approximately by the width of the garage door opening, z rollers protruding from the opposite side edges of the garage door, adjacent the horizontal upper edge thereof.

Each vertical side edge of the garage door is pivotably secured at a point beneath the associated roller to an arm that extends downwardly from the door when the latter occupies its open position.

Each arm is pivotably secured near its end remote from the garage door to a pivot bracket that is in turn rigidly secured e.g. to the frame defining the garage door opening.

A portion of each arm extends beyond the pivot point just referred to. A spring is attached, e.g. by means of a hook formed in the free end of the extended portion of the arm, between the arm and a further point located on the frame below the pivot point of the arm. Thus the pivot points of the arms act as a pair of fulcra by means of which it is possible to lever the lower portion of the garage door upwardly on opening thereof.

Since the weight of the upper part of the door is supported by virtue of the rollers running in the horizontally extending tracks, it is not necessary for the arms to support the entire weight of the garage door. Consequently, through judicious choice of the springs interconnecting the free ends of the arms and the respective further points on the frame, it is possible to devise a mechanism that is essentially "neutral", (i.e. that requires very little manual effort to open the door) with a slight biassing of the door towards its closed position after the door has moved from its open position more than a predetermined distance towards its closed position. This effect arises partly because a greater component of the force exerted by the door acts downwardly (i.e. towards the closed position) as the door moves away from its horizontal (open) position.

Furthermore, the transmission angle between the springs and the respective arms becomes more and more acute as the garage door approaches its closed position, and this reduces the mechanical advantage in the system and thus tends to bias the door towards its closed position once it has passed more than a predetermined distance from its fully open poSitiOn.

The horizontally extending tracks serve a dual purpose of supporting a significant part of the weight of the door, and in addition guiding in a cam-like manner the travel of the upper part of the garage door from its vertical, closed position (when it lies adjacent the garage door opening) to its horizontal, open position (when it lies retracted within the interior of the garage).

In the past, slideaway door gears have employed only a single spring at either side of the garage door to provide the necessary tension and assist the opening and closing motions of the door. However, it is expected shortly to become law in the member states of the European Union for slideaway door gears to include at least two tension springs acting in parallel at either side of the garage door. One proposal for satisfying this requirement is to provide a pair of yokes at each side of the garage door respectively securing the ends of the parallel springs to the associated arm and to the associated further location on the garage door frame.

Most manufacturers of slideaway door gears produce only a limited range of sizes of slideaway door gear. Whilst this approach is economical in terms of the manufacture of door gears, it gives rise to a disadvantage because most installers of garage door gears wish to be able to specify any of a wide range of garage doors for use with a particular slideaway door gear. Since the weights of garage doors vary significantly from one design to another, it is necessary for manufacturers of slideaway door gears to keep very large stocks of tension springs and supply the customer's slideaway door gears with a set of springs that is specifically tailored to the weight of door that the customer wishes to use.

It has previously been proposed to drill the free end of the arm extending beyond the pivot point therefor to form a number of spaced apertures. Such an arrangement provides for the position-adjustable mounting of the tension springs, and in part alleviates the problem identified above. However it has been found that such drilling of the arm is only a partial solution to the problem, and it still proves necessary for manufacturers of slideaway door gears to carry large stocks of springs of different lengths and rates. Thus the stock control disadvantages of prior art door gears still arise.

According to the invention, there is provided a slideaway door gear comprising a cam surface for guiding a first part of a moveable door; an arm pivotably securable (i) at a first location to a second part of such a door spaced from the first part thereof; and (ii) at a further location on the arm to an arm pivot fixed relative to the arm; at least one resilient member acting between the arm and a third location fixed relative to the arm such as to define a fulcrum at the arm pivot and assist movement of a door supported by the cam surface and the arm, wherein each end of the resilient member is securable in a plurality of positions to the arm and at the third location respectively.

The adjustable mounting of both ends of the resilient member, which in preferred embodiments is in the form of the parallel tension spring assembly described hereinabove, allows for fine tuning of the lengths and effective spring rates of the tension springs. It has surprisingly been found using a door gear in accordance with the invention that the overall number of different types and sizes of tension springs that a door gear installer must stock is dramatically reduced, perhaps to as little as a single spring type. Consequently, the manufacturer of a garage door gear of the slideaway type can make significant economies both because he no longer needs to purchase a wide range of springs; and also because the task of stock identification and storage is simplified or even eliminated entirely.

Conveniently the resilient member includes one or more tension springs, in particular two tension springs acting in parallel and secured at each end to a respective common component such as a yoke. These features advantageously permit the slideaway gear of the invention to comply with proposed legislation referred to hereinabove.

Preferably the resilient member is secured to the arm by means of a first anchor therefor pivotably securable in a plurality, in particular five, of spaced apertures formed in the arm. It is also preferable that the first anchor includes a pair of hooks for securing thereto a pair of tension springs; and optionally a through-going aperture for receiving a pivot bolt providing the pivotable mounting of the first anchor relative to the arm. Such an arrangement provides a convenient means of securing the resilient member in an adjustable manner.

It is also preferable that the resilient member is secured at the third location by means of a second anchor therefor pivotably securable in a plurality, in particular seven, of spaced apertures formed in a bracket secured at the third location.

It will thus be appreciated that in preferred embodiments of the invention there is provided a total of thirty-five different mounting positions of each resilient member. The provision of a large number of possible positions in which the resilient member can be secured advantageously assists in reducing the number of different springs that it is necessary for a slideaway gear manufacturer to keep.

In preferred embodiments the second anchor includes a through-going aperture for receiving a pivot bolt engageable in a guide yoke slidable relative to the bracket, the door gear including a member selectively engageable in the apertures formed in the bracket and with the guide yoke.

In practice, the bracket is a channel-section member with mutually aligned pairs of apertures formed in the opposed, upstanding walls thereof. The guide bolt passes through each of a pair of apertures in the side walls of the guide yoke and the aperture in the anchor. The guide yoke is secured relative to the bracket by one or more fixing screws. This arrangement facilitates adjustable positioning of the resilient member.

Conveniently, the arm includes elongate sub-arms transversely spaced from one another and interconnected by a third portion of the arm whereby to define a crank-like shape.

This feature advantageously permits the door gear of the invention to be installed in comparatively narrow garage door openings whilst still permitting modern motor car designs, having wide door mirrors to pass easily into the garage without fouling on the slideaway door gear arm. The invention is considered to reside in such a door gear when installed to support and guide a garage door between open and closed positions.

The invention is also considered to reside in such a door wherein the cranklike shape is disposed to conform generally to the profile of a motor car when the door gear occupies a position corresponding to an open garage door; and to a garage including a door gear as defined hereinabove.

Furthermore, this invention is considered to reside in such a garage including a garage door.

It is known to provide a weather seal for a garage door in the form of e.g.

rigid plates that are secured to the door frame in such a position as to overlap the edges of the door when closed. The weather seal prevents draughts and the ingress of water via the door edges.

In embodiments of the invention including the crank-like shape of the subarms, it is preferable that the door gear includes a flexible side seal or brush strip.

This feature maximises the benefit of the crank-like arms since it advantageously reduces the risk of damage occuring to motor vehicle body parts that protrude into the maximum-width portion of the door aperture defined by the sub-arms referred to above.

There now follows a description of a preferred embodiment of the invention, by way of example, with reference being made to the accompanying drawings in which: Figure 1 is a partially cut away perspective view of part of a garage showing the basic principles of a prior art slideaway door gear; Figure 2 is an elevational view from within a garage of a slideaway door gear in accordance with the invention; Figure 3 is a plan view of a spring anchor for use in the door gear of Figure 3 Figure 4 shows the components of Figure 2 when the garage door occupies its open position; Figure 5 shows a detail of part of the Figure 4 arrangement, illustrating use of the anchor yoke to secure the tension springs to the arm; and Figure 6 shows the arrangement for securing the opposite ends of the tension springs to the mounting bracket therefor.

Referring to the drawings, and in particular to Figure 1, there is shown a typical prior art slideaway door gear 10 installed in a garage 11.

Slideaway door gear 10 includes a pair of horizontally extending tracks 12 (of which only one is visible in Figure 1) suspended from a roof joist 13 of the garage 11 by means of suitable hangers 14 suspending one end of each track 12 inside the garage 11.

The end of each track 12 adjacent the garage door opening 15 is supported by means of a bracket 16 rigidly secured to the frame 15a defining the opening 15.

A garage door 17 is moveable between a closed position in which it lies vertically, filling the door opening 15 and an open position (illustrated) in which it lies generally horizontally, retracted within the garage 11 and adjacent the roof thereof.

Garage door 17 is supported on other side at its upper end by virtue of rollers 18 (of which only one is visible in Figure 1) disposed respectively at either side of door 17 and positioned to engage the respective tracks 12. The tracks 12 thus perform a dual function of supporting the weight of the upper part of the garage door 17 and in addition guiding the travel of the upper part of door 17 in a cam-like manner.

The lower part of the garage door 17 is supported at either side on an arm 19 pivotably secured to an edge thereof. Only one of the two arms 19 is visible in Figure 1.

The respective arms 19 are attached to the door 17 at their free ends. A point 20 on each arm is pivotably secured to a bracket 21 rigidly secured to the adjacent, vertical part of frame 15a. A portion 22 of each arm 19 extends beyond the point 20 and terminates in an anchorage point 23 for a tension spring 24 that is used to assist the opening and closing of door 17.

The end of each spring 24 remote from the associated arm 19 is secured to a fixed bracket 26 that is secured to the frame 15a adjacent the floor of the garage.

It will be appreciated therefore that prior art slideaway door gears can be operated to move the garage door 17 from the position shown in Figure 1 to a closed position, by virtue of the upper portion of the gear supported on the rollers 18 moving horizontally towards the door opening 15 and simultaneously pivoting downwardly about the rollers 18, whilst the respective arms 19 pivot about the respective points 20 (which act as fulcra for the arms 19) to support the lower part of the garage door and guide it to a closed position.

The springs 24 serve to counteract the weight of the door acting about the pivot points 20. The spring rates and the sizes of the springs 24 are chosen such that over the majority of the travel of door 17 it appears to be virtually weightless. As the garage door approaches its closed position, the respective arms 19 become virtually inverted as compared with the positions shown in Figure 1, and consequently the transmission angle between the springs 24 and the associated arms 19 becomes sufficiently acute that the springs 24 no longer support the entire weight of the lower part of the door 17.

Referring now to Figures 2-6, there is shown a slideaway door gear in accordance with the invention.

Door gear 10 of Figures 2-6 includes a pair 24a, 24b of springs (only one of which 24b is visible in Figure 2) arranged side by side to act in parallel on the arm extension 22.

At each end, the free ends of the springs 24a, 24b are secured to respective upper and lower anchor yokes 27, 28. The profile of each yoke is shown in Figure 3. Each yoke 27, 28 includes a pair of hooks 29a, 29b extending from either side of a flat member having a through-going bore formed therethrough. As is apparent from Figures 5 and 6, the loop-like ends 30 of the respective springs 24a, 24b are receivable in the hooks 29a, 29b. Thus a pair of springs 29a, 29b joined at either end by a respective anchor yoke 28, 29 constitutes a resilient member that is connectable between the end of arm extension 22 and the further anchorage 23 to be described in greater detail below.

A respective such resilient member is disposed at either side of the garage door frame which is in effect fitted with two mirror image slideaway door gears.

As is evident from Figure 5, the upper anchorage yoke 27 is secured pivotably to the arm extension 22 by virtue of a pivot bolt 32 passing through the aperture 33 formed in anchorage yoke 27. Pivot bolt 32 has rotatably mounted thereon a washer 34 that serves as a thrust surface for anchorage yoke 27. Washer 34 is secured against movement of the free end of bolt 32 by virtue of a split pin 35 passing through an aperture extending transversely through bolt 32.

Pivot bolt 32 passes through one of five apertures 37a-37e formed transversely through arm extension 22. The head 32a of pivot bolt 32 lies on the opposite side of arm extension 22 to that on which the springs 24a, 24b lie with the result that the springs 24a, 24b are pivotably secured jav anchorage yoke 27 to the arm extension 22.

It will be appreciated that by removing split pin 35 and washer 34 it is readily possible to re-position yoke 27 so that it is secured pivotably at any one of the apertures 37a-37e.

In the embodiment of the invention shown, the main pivot point 20 and bracket 21 defining pivot point 20 are conventional. Bracket 21 is constituted as an L-shaped member the upstanding arm of which is formed with a through-going aperture adapted to receive a permanently secured pivot pin that passes in turn through a further aperture 38 formed in arm extension 22 at a point spaced from the five apertures 37a37e referred to above.

The lower end of each pair of springs 24a, 24b is in the embodiment shown secured to a lower anchorage yoke 28 of substantially similar design to anchorage yoke 27. A further pivot bolt 42 passes through lower anchorage yoke 28 by means of the aperture 43 formed therein and is pivotably secured at either end in slidable, channel-section member 44 that slides in a channel-section bracket 45 that is rigidly secured to a vertical member of the frame.

Channel-section member 44 includes a base portion 44a and respective, spaced, upstanding side walls 44b, 44c. Each side wall 44b, 44c has a through-going aperture to receive pivot bolt 42. Pivot bolt 42 is secured at either end in member 44 by virtue of a washer 46 and split pin 48 in a manner analogous to the fixing of bolt 32 previously described.

A fixing screw 36 passes through aligned apertures 49 formed in the upstanding side walls 45b, 45c of bracket 45 and through aligned apertures formed in the upstanding side walls of member 44, whereby to secure member 44 and bracket 45 together. There are seven pairs of apertures 49a-49g formed in a linearally spaced, mutually aligned arrangement in bracket 45 so that the member 44 is securable in any of seven possible positions spaced longitudinally from one another.

It will thus be appreciated that the upper end of the resilient member constituted by springs 24a, 24b as shown in Figure 2 is securable in up to five positions on arm extension 22; and the lower end thereof in up to seven positions in bracket 45. Consequently, there are thirty-five possible adjustments of the resilient member constituted by springs 24a, 24b thereby allowing a great range of adjustment of the forces applied to arm extension 22.

However it will be appreciated that other plural numbers of apertures may be formed in arm extension 22 and the side walls of bracket 45 if desired.

The end of each arm 19 remote from the apertures 37a-37e is pivotably securable to the garage door 17 by virtue of a bracket of known design having a pair of fixing flanges 50 upstanding from the garage wall and spaced from a bracing flange 51. The flanges 50, 51 are formed with through-going apertures for the pivotable securing therein of suitable pivot bolts 53 that provide for the pivotable support of the garage door lower portion relative to each arm 19.

The portion of each arm 19 between the pivot point 20 and the end secured to the garage door 17, which portion constitutes in the embodiment shown a major part of the length of each arm 19, is spaced from the arm extension 22 in a direction generally transverse to the longitudinal direction of the arm 19. A crank portion 54 interconnects the two portions of each arm 19. It will be appreciated that since on opening of the door the arms 19 each adopt the position shown in Figure 4, the arms 19 do not encroach into the opening 15 below the level of the crank portion 54.By judicious choice of the length of the parts of arm 19 and of the position of pivot point 20, there can be provided sufficient space beneath the crank portion 54 when the garage door is open to permit a modern design of motor vehicle having comparatively wide door mirrors to pass into the opening 15 without contacting the arms 19 even when the opening 15 is only slightly wider than the widest part of such a motor car.

Also visible on Figure 4 is a side seal 60 that may optionally be included in the door gear 10, secured e.g. on the forwardmost edge of each member 15a so as to overlie, and seal against draughts, rain, etc., the gap between the garage door 17 and the members 15a when the door occupies its closed (vertical) position.

In the embodiment of Figure 4, the seal 60 is formed as a flexible extrusion so that vehicle body parts in the region 60a may pass into the garage without suffering damage that would be caused by a rigid side seal of the kind used in prior art door gears.

Side seal 60 includes a cutout 60b that allows the crank portion 19 to pass between is closed and open positions without fouling on the seal 60.

An alternative form of side seal 60, illustrated schematically in Figure 2, employs a brush strip instead of a flexible extrusion. In such an embodiment there is no need for cutout 60b since the member 19 tends to part the brushes of the strip on movement of the door between its closed and open positions. Other flexible side seals may also be employed.

The side seals may optionally be used e.g. in conventional garage door gears or door gears according to the invention that lack the cranked sub-arms shown in Figure 4.

For the avoidance doubt, the invention is not limited to slideaway door gears that are intended solely for use in domestic garages. On the contrary, the door gear of the invention can be employed for use with a great variety of other doors, and need not be configured to provide for the opening of a door in a vertical direction. It is possible to devise variants within the scope of the invention that provide for the opening of doors horizontally or even along paths that are neither exclusively horizontal nor exclusively vertical.

Furthermore, the resilient member 24 need not be in the form described in detail herein, and may take a variety of different forms. For example, the resilient member may be arranged to provide compressive forces instead of tensile forces acting about the fulcrum 21.

Claims (19)

1. A slideaway door gear comprising: a cam surface for guiding a first part of a moveable door; an arm pivotably securable (i) at a first location to a second part of such a door spaced from the first part thereof; and (ii) at a further location on the arm to an arm pivot fixed relative to the arm; at least one resilient member acting between the arm and a third location fixed relative to the arm such as to define a fulcrum at the arm pivot and assist movement of a door supported by the cam surface and the arm, wherein each end of the resilient member is securable in a plurality of positions to the arm and at the third location respectively.

2. A door gear according to Claim 1 wherein the resilient member includes one or more tension springs.

3. A door gear according to Claim 2 wherein the resilient member includes two tension springs acting in parallel and secured at each end to a respective, common component.

4. A door gear according to any preceding claim wherein the resilient member is secured to the arm by means of a first anchor therefor pivotably securable in a plurality of spaced apertures formed in the arm.

5. A door gear according to Claim 4 wherein the arm includes 5 spaced apertures.

6. A door gear according to Claim 4 or Claim 5 wherein the first anchor includes a pair of hooks for securing thereto a pair of tension springs.

7. A door gear according to Claim 6 wherein the first anchor includes a throughgoing aperture for receiving a pivot bolt providing the pivotable mounting of the first anchor relative to the arm.

8. A door gear according to any preceding claim wherein the resilient member is secured at the third location by means of a second anchor therefor pivotably securable relative to a plurality of spaced apertures formed in a bracket secured at the third location.

9. A door gear according to Claim 8 wherein the bracket includes seven spaced apertures.

10. A door gear according to Claim 8 or Claim 9 wherein the second anchor includes a pair of hooks for securing thereto a pair of tension springs.

11. A door gear according to any one of Claims 8 to 10 wherein the second anchor includes a through-going aperture for receiving a pivot bolt engageable in a guide yoke slidable relative to the bracket, the door gear including a member selectively engageable in the apertures formed in the bracket and with the guide yoke.

12. A door gear according to any preceding claim wherein the arm includes two elongate sub-arms transversely spaced from one another and interconnected by a third portion of the arm whereby to define a crank-like shape.

13. A door gear according to Claim 12 when installed to support and guide a garage door between open and closed positions.

14. A door gear according to Claim 13 wherein the crank-like shape is disposed to conform generally to the profile of a motor car door when the door gear occupies a position corresponding to an open garage door.

15. A door gear according to any one of Claims 12 to 14 including a flexible side seal or brush strip.

16. A garage including a door gear according to any preceding claim.

17. A garage according to Claim 16 including a garage door.

18. A door gear generally as herein described with reference to or as illustrated in Figures 2 to 6 of the accompanying drawings.

19. A garage generally as herein described with reference to Figures 2 to 6 of the accompanying drawings.