AU2019100867A4 - A gravity hinge and a gravity hinge kit - Google Patents

Abstract

Abstract Disclosed herein is a gravity hinge, and a gravity hinge kit. r- r r-U 00l t.0 N

Description

The disclosure herein generally relates to gravity hinges and gravity hinge kits.

Background

A movable barrier in the form of a door hung with a gravity hinge can be gravity actuated, that is closed or opened without further actuation, for example hand actuation. Toilet cubical doors, for example, may be hung with gravity hinges, however windows, panels and gates may also be gravity hung.

Misalignment between gravity hinges attached to a door are common, resulting in a door closure rate that is less than that desired. Consequently, the door may close too slowly or not at all. Hinge misalignment may be caused by panel bowing or installation imperfection. Lubrication may be squeezed out of the gravity hinges or go off, which may further slow door closure.

Gravity hinges arranged for a stronger closing force (by having, for example, an increased height difference between the open position and closed position) may be used to compensate for hinge misalignment or insufficient lubrication, however the door may then close too fast, especially if the hinges attached to the door are aligned. This may not be desirable because the door may slam shut, which may produce noise, fatigue or overload a door stop, and cause injury if a person is disposed between the door and the adjacent doorjamb, for example. Alignment and changes in lubrication can change with humidity, use and abuse, wear, and so the optimal closing force changes.

It may not be possible to manufacture a prior art gravity hinge with exactly the right closing force for a door in view of continual alignment and lubrication changes.

Some prior art hinges may have a hinge barrel (a “barrel”) and a hinge leaf that are integral to each other. To form such a hinge barrel, a side of a sheet of metal may be rolled back on itself to form the hinge barrel, and the sheet configuration of another side of the sheet of metal may be retained for the hinge leaf. This may, however, result in a gap in the form of a slot where an edge of the sheet of metal is rolled over to be adjacent the leaf. Such a gap may allow ingress of grime and water into the hinge, which may corrode or adversely affect the working of the hinge. Even when the rolled over edge of the sheet of metal touches the hinge leaf, the touching

2019100867 06 Aug 2019 surfaces may not form a seal, in which case moisture and grime may still enter. The gap may also weaken the hinge 10. The hinge 10 with such a gap may be more easily distorted or broken, particularly for heavier doors. The gap may also reduce the rigidity of the hinge 10, which may result in misalignments and reduced performance, particularly for heavier doors. Such prior art hinges may rub against the surfaces that they are attached to, which may mark or damage the surfaces and impede operation.

It may be desirable to have a gravity hinge that provides sufficient closing force even when gravity hinges attached to a door are misaligned, or when insufficiently lubricated, for example. It may be desirable to have a gravity hinge that does not close too fast. It may be desirable to 10 have a gravity hinge that can accommodate changes in alignment and lubrication.

Summary

An aspect of the present invention provides a gravity hinge comprising: a part comprising:

a leaf pivotable around a hinge axis and for attachment to one of a movable barrier and a structure adjacent the movable barrier;

a component on the hinge axis, and comprising opposite sides that are each attached to the leaf;

a winding cam surface;

another part comprising:

another leaf pivotable around the hinge axis and for attachment to the other one of the movable barrier and the structure;

another component on the hinge axis, and comprising opposite sides that are each attached to the other leaf;

a cam follower arranged to follow the winding cam surface for increasing the separation of the component and the other component; and a damper operationally coupled to the component and the other component to moderate reduction of the separation between the component and the other component.

A gravity hinge defined by claim 1 wherein the leaf is gaplessly attached to the component, and the other leaf is gaplessly attached to the other component.

2019100867 06 Aug 2019

	A gravity hinge defined by either one of claim 1 and claim 2 wherein the damper comprises a complete damper unit. Another aspect of the present invention provides a gravity hinge comprising: a part comprising:
5	a leaf pivotable around a hinge axis and comprising an attachment surface for attachment to one of a movable barrier and a structure adjacent the movable barrier; a component on the hinge axis, wherein the attachment surface is rearwardly displaced relative to the component;
10	a winding cam surface; another part comprising: another leaf pivotable around the hinge axis and comprising another attachment surface for attachment to the other one of the movable barrier and the structure;
15	another component on the hinge axis, wherein the other attachment surface is rearwardly displaced relative to the other component; a cam follower arranged to follow the winding cam surface for increasing the separation of the component and the other component; and
20	a damper operationally coupled to the component and the other component to moderate reduction of the separation between the component and the other component. Yet another aspect of the present invention provides A gravity hinge kit comprising: a part comprising:
25	a leaf pivotable around a hinge axis and for attachment to one of a movable barrier and a structure adjacent the movable barrier; a component disposed on the hinge axis; a winding cam surface; another part comprising:
30	another leaf pivotable around the hinge axis and for attachment to the other one of the movable barrier and the structure; another component disposed on the hinge axis; a cam follower arranged to follow the winding cam surface for

2019100867 06 Aug 2019 increasing the separation of the component and the other component; and a damper operationally coupled to the component and the other component to moderate reduction of the separation between the component and the other component.

Any of the various features of each of the above disclosures, and of the various features of the embodiments described below, can be combined as suitable and desired.

Brief description of the figures

Embodiments will now be described by way of example only with reference to the accompanying figures in which:

Figure 1 shows an exploded front isometric view of an embodiment of a gravity hinge.

Figure 2 shows an isometric view of a damper of the gravity hinge of figure 1, with a housing shown transparently for illustrative purposes.

Figure 3 shows a front elevational view of the gravity hinge of figure 1, as if long supporting the weight of an attached door, and in an unfolded configuration, with a portion of a housing shown transparently for illustrative purposes.

Figure 4 shows a front elevational view of the gravity hinge of figure 1, as if supporting the weight of the attached door, in a folded configuration, with the housing shown transparently for illustrative purposes.

Figure 5 shows a front elevational view of the gravity hinge of figure 1 after being relatively quickly unfolded from the folded configuration of figure 4.

Figure 6 shows a plan view of a part of the gravity hinge of figure 1.

Figure 7 shows a top isometric view of the part of figure 6.

Figure 8 shows a plan view of a cam insert for the part of figure 6.

Figure 9 shows a bottom isometric view of another part of the hinge of figure 1.

Figure 10 shows a bottom view of the other part of figure 9.

Figure 11 shows a bottom view of a cam follower insert for the other part of figure 9.

2019100867 06 Aug 2019

Figure 12 shows a front elevational view corresponding to figure 3, with a portion of the housing cut away.

Figure 13 show a partially transparent front elevational view of a damper assembly for attachment to a movable barrier.

Description of embodiments

Figure 1 shows an exploded front isometric view of an embodiment of a gravity hinge generally indicated by the numeral 10. The gravity hinge 10 comprises a part 12 comprising a hinge leaf 18 for attachment to one of a movable barrier in the form of a door and structure adjacent the movable barrier in the form of a doorjamb. The leaf is pivotable around a hinge axis 26. The 10 part 12 comprises a component 36 on the axis 26. The part 12 comprises comprising a winding cam surface 24, which turns around axis 26. The gravity hinge 10 comprises another part 14 comprising another hinge leaf 19 for attachment to the other one of the movable barrier and the structure. The other leaf is pivotable around the hinge axis 26. The other part 14 comprises another component 38 on the axis 26. The other part comprises a cam follower 32 arranged to 15 follow the cam surface 24 for increasing the separation of the component 36 and the other component 38. The gravity hinge 10 comprises a damper 34 in the form of a linear damper operationally coupled to the component 36 and the other component 38 to moderate reduction of the separation between the component 36 and the other component 38 along the axis 26.

The leaves 18 and 19 comprise rear facing attachment surfaces 80,86 that in use generally abut, 20 for example, a door and a doorjamb. Hinge leaf 18 comprises a plate 20 defining a plurality of fastener apertures, for example fastener aperture 22. In use, fasteners in the form of screws may be inserted through the plurality of fastener apertures 22 and engage the one of the door and the doorjamb. Alternatively, the leaf 18 may be fastened with suitable rivets or adhesive, for example. The leaf 18 is configured to be attached. Other hinge leaf 19 comprising a plate 21 25 defining a plurality of fastener apertures, for example fastener aperture 23, similarly for attachment. Similarly, the other leaf 19 is configured to be attached.

The cam surface 24 is in the form of a spiral cam surface. In this but not all embodiments, the spiral cam surface has a constant radius from the axis 26 and a constant pitch (i.e. a helical cam surface). The cam surface 24 may trace an out an angle in the range of 90 degrees - 360 degrees, for example, however the angle may be lesser or greater.

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The hinge 10 comprises a hinge pin 64. The hinge pin 64 is parallel to the axis 26. While the hinge pin 64 extends along the axis 26, it may not in an alternative embodiment. The other part 14 is translatably mounted on the hinge pin 64.

The component 36 is in the form of a housing or hinge barrel centred on the axis 26 and attached to the hinge leaf 18 and defining a housing cavity. In the context of the present specification, a hinge barrel in not necessarily round in cross section, but understood to be a housing for components disposed within the hinge barrel, for example hinge pin 64. The hinge barrel may have longitudinal edges, or generally any suitable shape, for example. The housing 36 comprises a circular cylindrical shell defining the housing cavity, which has a circular cross section, however in alternative embodiments the housing cavity may have any suitable cross sectional shape. A cam insert 40 is disposed in the housing 36, within the housing cavity, having been inserted therein, and is seated on a housing end-wall 31 at the bottom of the housing cavity. The cam insert 40 is centred on the axis 26. The cam insert 40 comprises the cam surface 24 at a proximal end 25 of the cam insert 40. The distal end 27 of the cam insert 40 is at the distal end

43 of the housing 36. The cam insert 40 is press-fitted into the housing 36, however it may be alternatively attached with a fastener, a suitable adhesive, brazed, or generally attached by any suitable way. The housing 36 and the cam insert 40 comprise cooperating meshing features 47,49 in the form of a key and a key way, or alternatively splines and grooves or generally any suitable cooperating meshing features. Generally, the cam insert 40 is rotationally fixed within the housing 36.

Opposite sides 92,94 of the housing 36 are attached to the leaf 18. The housing 36 and the leaf 18 are gaplessly attached. That is, there is no gap adjacent the joint between the housing 36 and the leaf 18. Opposite sides 96,98 of the other housing 38 are attached to the other leaf 19. The other housing 38 and the other leaf 19 are also gaplessly attached. The housing 36 and other housing 38 completely cross sectionally enclose the housing cavity and the other housing cavity respectively, that is without any gap. Gap free attachment may not be essential, however, attachment with a gap may be inferior.

The other component is in the form of another housing 38or another barrel centred on the axis 26 and attached to the other hinge leaf 19. The other housing 38 comprises a circular cylindrical shell defining another housing cavity having a circular cross section, however the other housing cavity may have any suitable cross sectional shape. The cam follower 32, which is in the form of a cam follower insert, is disposed in the other housing 38, within the other housing cavity, having been inserted therein. The cam follower insert 32 has a perimeter flange 66 that is seated

2019100867 06 Aug 2019 on the rim 68 of the other housing 38. The perimeter flange may comprise a material having a lower friction coefficient than the other housing 68, for example. The cam follower insert 32 is centred on the axis 26. The cam follower 32 comprises a cam surface bearing 33 at the proximal end 35 of the cam follower insert 32. The cam bearing surface 33 is in the present but not all embodiments congruent with the cam surface 24, however the cam bearing surface 33 may be congruent with only a portion of the cam surface 24. The cam bearing surface 33 is in the form of a spiral-bearing (in this but not all embodiment a helical-bearing), winding around the axis 26. The cam surface bearing 33 may not, however, in all embodiments be congruent with the cam surface 22. The cam follower insert 32 is seated on a seat 37 within the other housing 38.

The cam follower insert 32 and the other housing 38 comprise cooperating meshing features in the form of a key 41 and at least one key way 45, or alternatively splines and groves or generally any suitable cooperating meshing features. The cooperating meshing features may be configured for the cam follower insert 32 to have a plurality of alternative fixed rotational positions within the other housing 38. For example, the housing 38 defines a plurality of spaced apart interior longitudinal grooves 45 for receiving a key 41 at each of the different rotational positions and the follower insert 32 has a longitudinal key 41. Alternatively, the housing 38 may comprise the key - the key being attached or integral thereto - and the follower insert 40 may define at least one keyway. The cooperating meshing features may allow for the hinge to be configured to be fitted either flat or bent, depending on the circumstances. Alternatively, the follower insert 32 may be press-fit within the other housing cavity or otherwise attached to the other housing 68. Generally, the cam insert 40 is rotationally fixed within the housing 36. Alternatively, the cam 40 and the housing 36 may have cooperating meshing features for selective rotational fixing.

A bush 60 comprising an outwardly flanged rim 62 is disposed within the proximal end 41 of the barrel 36. The outwardly flanged rim 62 caps the rim of the housing 36 and spaces apart the barrel 36 and the other barrel 38. In the present but not all embodiments, the flanged bush 60 comprises a relatively low friction material, that is the flange has a coefficient of friction that is less than the barrel 36.

The attachment surface 80 of the leaf 18 is rearwardly displaced relative to the housing 36. A surface 84 of the housing 36 directly behind the hinge pin 64 is forward of the attachment surface 80. A step 85 is intermediate the attachment surface 80 of the leaf 18 and the surface 84 of the housing 36. The attachment surface 86 of the leaf 19 is rearwardly displaced relative to the housing 38, such that the surface 88 of the housing 38 directly behind the hinge pin 64 is forward of the attachment surface 86. Another step 90 is intermediate the attachment surface 86

2019100867 06 Aug 2019 of the leaf 19 and the surface 88 of the housing 38. The rearward displacements of the leaves 18,19 with respect to housings 36,38 may prevent the housings 36,38 rubbing against the door or doorjamb, for example, which may mark, and may fried onally impede operation of the hinge

10. In an alternative embodiment, at least one of the step 85 and the other step 90 may be replaced with a curved surface, a ramp surface, or generally any suitably configured transition surface.

The part 12 and the other part 14 are joined with a joint orientated for changing an axial separation between the component 36 and the other component 38. The joint comprises the hinge pin 64 extending along the axis 26 and disposed in the barrel 36 and the other barrel 38. The joint is in the form of a sliding-rotary joint. The hinge pin 64 is also disposed in the cam insert and the cam follower insert 32. The cam insert 40 and the cam follower 32 each define a hinge pin receiving cavity in which the hinge pin 64 is received. The hinge pin 64 is disposed within the cam insert 40 and aperture 72 defined at the distal end 27 of the cam insert 40, and is seated on the end wall 31 at the bottom of the housing cavity. The hinge pin 64 is press fitted into the cam insert 40.

The damper 34 lies along the axis 26 and in the present embodiment is in the form of a complete damper unit. A complete damper unit may be less likely to leak than one that is not complete. Leakage may reduce the damping effect of the damper 34, and the leaked damper fluid (generally, but not necessarily an oil) may be a slip hazard, or attract grime which may interfere 20 with the hinge’s bearings. Figure 2 shows a schematic diagram of the damper 34. The damper comprises a piston 46 parallel to and extending along the axis 26 and a piston biasing element in the form of a compression spring arranged to outwardly bias the piston 46. The piston may not extend along the axis in an alternative embodiment. The damper comprises a dashpot 50 comprising an outer damper housing 53 defining a fluid chamber 51 in which is disposed a viscous fluid in the form of an oil. An oil seal 52 retains the oil in the damper 34 and provides a piston port through which the piston 46 passes. The damper may also comprise a valve 54, an absorber 56 and a closure 58. Generally, any suitable form of damper may be used as suitable, for example a magnetic damper.

The damper 34 is configured to frictionally retard movement of the piston 46 when actuated, for 30 example by door weight being applied to the piston 46 via the other leaf 19. The friction is in the present embodiment in the form of viscous friction generated in the viscous fluid. The frictional force may be approximately proportional to the velocity of the piston 46, slowing withdrawal of the piston 46 and absorbing energy.

2019100867 06 Aug 2019

The damper 34 extends between a proximal end 44 and a distal end 42. The proximal end 44 is operationally coupled to the part 12 and the distal end 42 is operationally coupled to the other part 14. The damper 34 is disposed in the cam follower insert 32, passing through an aperture defined by the distal end of the cam follower insert 32, and the distal end 42 of the damper 34 is 5 seated at a seat 70 within a reduced inner diameter portion 74 of the other housing 38.

Operational coupling of the damper to the part and the other part is now described. The proximal end 44 abuts hinge pin 64. The hinge pin 64 abuts part 12. The proximal end 44 can exerts a force on the hinge pin 64 and in turn the part 12, in a direction opposite that to the other part 14. At least one intermediate part in the form of at least one spacer, for example, may be placed between the proximal end 44 and the hinge pin 64, and/or the hinge pin 64 and the part 12.

The reduced inner diameter portion 74 has an inner diameter that is less than that of an adjacent portion 76 of the other housing 38. The reduced inner diameter portion 74 may allow seating of a relatively small diameter damper, which may have the required frictional damping and spring 15 characteristics, for example. Relatively small diameter dampers may also reduce costs. The outer diameter of the damper 34 is less than that of the pin 64 so that it can be easily removed from the cavity in which the pin 64 and damper are disposed. In an alternative embodiment, however, the outer diameter of the pin 64 and the damper 34 are equal. In an alternative embodiment, the damper 34 is seated within the cam follower insert 32. The piston 46 is biased by the piston 20 biasing element 48 into the hinge pin 64.

Figure 3 shows the hinge 10, as if long supporting the weight of an attached door (“resting position”) and so having a minimum separation between the component 36 and the other component 38. The piston 46 has a lesser extension. When the hinge 10 is folded from the unfolded configuration (figure 3) to the folded configuration (figure 4), the cam follower 32 2 5 slides over and up the cam surface 24 of the cam insert 40, increasing the separation of distal ends of the cam insert 40 and the cam follower insert 32, and so increasing the separation of the component 36 and the other component 38. The piston 46 is extended by the piston biasing element 48 to have a greater extension. When part 12 is attached to the doorjamb and the other part 14 is attached to the door, the height of the door is increased by folding the hinge from the 30 unfolded configuration (figure 3) to the folded configuration (figure 4). The increase in height of the door increases the door’s potential energy which the hinge 10 can release by allowing the door height to decrease, wherein the cam follower 32 slides over and down the cam surface 24. As the cam follower 32 slides over and down the cam surface 24, the piston 46 is pushed inwardly. The damper 46 resists the decrease in the height of the door. That is, the damper ίο

2019100867 06 Aug 2019 moderates reduction of the separation between the component 36 and the other component 38 along the axis 26.

The handedness of the spiral cam surface 24 is reversed in an alternative embodiment of a hinge which self closes from the unfolded to folded configuration, instead of the folded to unfolded configurations.

Figure 5 shows the gravity hinge 10 after being relatively quickly unfolded from the folded configuration of figure 3, so that the piston has not had sufficient time to withdraw, and so the cam surface 24 is separated from the cam follower 40. The separation d of the component 36 and the other component 38 decreases when the weight of the movable barrier is applied, but the 10 rate of decrease is moderated by the damper 34, which may slow the rate at which the door drops, and so closes. The door, however, may be opened and closed without significant resistance from the damper 34. When the gravity hinge 10 is unfolded at an unfolding velocity greater than a threshold unfolding velocity defined by the damper 34, the cam follower 32 and the cam surface 22 separate. Consequently, the damper action of the damper 34 does not resist 15 unfolding, and the friction between the cam surface 24 and the follower 32 is reduced. The damper 34 may not significantly resist a person opening or closing a movable barrier to which the hinge is attached.

The cam surface 24 may be relatively steep, however the door closing speed may be dictated by the damper 34.

The damper 34 is in the illustrated embodiments, but not all embodiments, removably mounted.

The damper 34 may be removed from the hinge 10 and the hinge 10 is operable without the damper 34. The damper may be replaced when worn. Removal and/or replacement of the damper 34 is relatively easy because it is a complete damper unit. The damper 34 is more likely to be installed correctly because it may be relatively easy to install a complete damper.

A gravity hinge kit is provided. The gravity hinge kit comprises the hinge 10 in a disassembled state represented by figure 1, for example. Generally, the kit may come partially assembled, as suitable and desired.

The cam insert 40 and the cam follower 32 each comprise polymer in the form of nylon, however they may generally comprise any suitable material, examples of which include but are 30 not limited to polyoxymethylene, and steel. Nylon and polyoxymethylene have relatively low coefficients of friction. Cam insert 40 and cam follower 32 may be injection molded. The parts and 14 comprise zinc or zinc alloy (e.g. ZAMAK), however they may generally comprise any

2019100867 06 Aug 2019 suitable material, examples of which include but are not limited to steel and polymer. Parts 12 and 14 may be cast, for example die cast. The hinge pin 64 comprises a metal in the form steel but may generally comprises any suitable material, examples of which include but are not limited to zinc alloy and polymer. The damper may be any suitable damper. Some dampers used for kitchen cabinets may be suitable.

When assembling the gravity hinge 10, the damper 34 is operationally coupled to a part 12 and another part 14. Optionally, depending on the state of preassembly, the following steps may also be performed during assembly of the gravity hinge:

• The cam insert 40 may be disposed in housing 36.

· The cam follower insert 32 may be disposed in the other housing 38.

• The bush 60 may be coupled to the housing 36.

• The pin may be disposed in at least one of the housing 36 and the other housing 38.

Figure 13 shows a partially transparent plan view of a damper assembly 100 for attachment to a movable barrier, where parts similar and/or identical in form and/or function to those in figures 1

- 12 are similarly number. The damper assembly 100 comprises a part 12 comprising a leaf 18 for attachment to one of a movable barrier and a structure adjacent the movable barrier. The damper assembly 100 comprises another part 14 comprising another leaf 19 for attachment to the other one of the movable barrier and the structure. The damper assembly 100 comprises a damper 34 in the form of a linear damper and operationally coupled to the part 12 and the other part 14 to moderate reduction of a separation between components 102 and 106. At least one of the part 12 and the other part 14, in this embodiment part 14, is mounted for pivoting around an axis of the damper 34, or in close proximity to the axis of the damper 34. The other part 14 comprises a housing 102 defining a housing cavity 104 in which an end 44 (or opposite end 42) of the damper 34 is received. The part 12 comprises a damper receiving platform 106 which receives another end 42 of the damper 34. In an alternative embodiment, the part 12 may comprise the housing 102 and the other part 14 may comprise the housing 102.

Now that embodiments have been described it will be appreciated that some embodiments may have some of the following advantages:

• The housings may have square or generally any suitable cross section.

· Attachment of opposite sides of the housing and other housing to the leaf and other leaf may improve performance, strength and rigidity.

• Gapless attachment of leaves and components may improve performance.

2019100867 06 Aug 2019 • The use of a complete damper unit may reduce likelihood of leaks, and improve the likelihood of correct installation.

• The housings may not rub on a surface the hinge is attached to which may reduce marking and improve operation.

· Sufficient door closing force may be generated even with hinge misalignment, and manufacturing variations, installation variations and environmental variations. A stiffer damper may be used for heavier doors, for example.

• Lubrication requirements may be reduced compared to the prior art. This may increase reliability and may reduce maintenance.

· Doors may not self-close too quickly. This may reduce door banging, may reduce fatigue and overload on a door stop, and may prevent injury.

• Changes in lubrication, alignment, wear etc. may be accommodated.

• Embodiments may suit a wide variety of door sizes, degrees of misalignment etc.

• Unnecessary resistance may not be experienced during hand actuation of the door, and so the door may be moved without unnecessary delay, which may be desirable for applications including but not limited to hanging toilet cubical doors.

• The dampener may be removed for use therewithout, or the damper may be removed and replaced when worn, or different dampening strength required.

Variations and/or modifications may be made to the embodiments described without departing from the spirit or ambit of the invention. For example:

• the joint may comprise at least one bushing or roller bearings.

• The movable barrier may comprise a panel, door, gate, window or generally any form of movable barrier.

• The structure may comprise a doorjamb, post, window jamb, window casing, or

5 generally any suitable structure.

• The cam surface may not be part of an insert. The cam surface may be integral with the hinge leaf, the cam surface may be of a helical rim of the housing.

• The cam surface need not be helical, and may have a variable pitch, for example.

• The housings and housing cavities may have generally any suitable cross sectional shape, for example circular.

• The cam surface may wind around the axis in one direction, and then the other.

• The cam surface and the cam follower insert may not be centred on the axis.

2019100867 06 Aug 2019 • The cam follower may alternatively or additionally comprise a block, ball bearing or generally have any suitable form.

• The fasteners may comprise stainless steel screws, clips, rivets, or generally any suitable form of fastener comprising generally any suitable material.

· The hinge pin may be in the form of a tube, and the damper may abut the perimeter thereof, or the tube may be closed with a cap or closure that the dampener abuts.

• At least one of the component and the other component may not be housings. For example, the component, the hinge pin and the cam surface may be parts of a solid piece of cast metal, and the component may not define a cavity.

· The damper may be elongated and act as a hinge pin.

The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. Reference to a feature disclosed herein does not mean that all embodiments must include the feature.

Prior art, if any, described herein is not to be taken as an admission that the prior art forms part 15 of the common general knowledge in any jurisdiction.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises or “comprising is used in an inclusive sense, that is to specify the presence of the stated features but not to preclude the presence or addition of 20 further features in various embodiments of the invention.

Claims (7)

1. A gravity hinge comprising:

a part comprising:

a leaf pivotable around a hinge axis and for attachment to one of a

5 movable barrier and a structure adjacent the movable barrier;

a component on the hinge axis, and comprising opposite sides that are each attached to the leaf;

a winding cam surface;

another part comprising:

10 another leaf pivotable around the hinge axis and for attachment to the other one of the movable barrier and the structure;

another component on the hinge axis, and comprising opposite sides that are each attached to the other leaf;

a cam follower arranged to follow the winding cam surface for

15 increasing the separation of the component and the other component;

and a damper operationally coupled to the component and the other component to moderate reduction of the separation between the component and the other component.

20

2. A gravity hinge defined by claim 1 wherein the leaf is gaplessly attached to the component, and the other leaf is gaplessly attached to the other component.

3. A gravity hinge defined by either one of claim 1 and claim 2 wherein the damper comprises a complete damper unit.

4. A gravity hinge comprising:

25 a part comprising:

a leaf pivotable around a hinge axis and comprising an attachment surface for attachment to one of a movable barrier and a structure adjacent the movable barrier;

a component on the hinge axis, wherein the attachment surface is

30 rearwardly displaced relative to the component;

a winding cam surface;

another part comprising:

2019100867 06 Aug 2019 another leaf pivotable around the hinge axis and comprising another attachment surface for attachment to the other one of the movable barrier and the structure;

another component on the hinge axis, wherein the other attachment

5 surface is rearwardly displaced relative to the other component;

a cam follower arranged to follow the winding cam surface for increasing the separation of the component and the other component; and a damper operationally coupled to the component and the other component to

10 moderate reduction of the separation between the component and the other component.

5. A gravity hinge kit comprising:

a part comprising:

a leaf pivotable around a hinge axis and for attachment to one of a

15 movable barrier and a structure adjacent the movable barrier;

a component disposed on the hinge axis;

a winding cam surface;

another part comprising:

another leaf pivotable around the hinge axis and for attachment to the 20 other one of the movable barrier and the structure;

another component disposed on the hinge axis;

a cam follower arranged to follow the winding cam surface for increasing the separation of the component and the other component; and

25 a damper operationally coupled to the component and the other component to moderate reduction of the separation between the component and the other component.