HK1170557A - Hinge having self-centering means - Google Patents

Description

Hinge with self-centering assembly

Technical Field

The present invention relates to hinges for doors, particularly glass doors, particularly but not exclusively frameless glass doors.

Background

Frameless glass doors require a door stop to be in the closed position. An inner door stop is disclosed in, for example, US 6560821. Patent No. WO2011/020630 discloses a glass door hinge with an in-door stop device, comprising: a housing; a mount connecting the housing to a support member; a pair of clamps; an axial shaft; and a plurality of biasing members arranged to engage the shaft to return the jaws to one of a plurality of positions selected from a closed position and one or more open positions; wherein the shaft carries a plurality of centering surfaces, each biasing member being arranged to apply a force to a corresponding centering surface to center the clamp in one or more of the positions. The disclosure of this specification is incorporated into the disclosure of this specification by reference for all purposes.

Disclosure of Invention

According to the present invention, a door hinge with an in-door stopping device includes:

a housing;

a mount connecting the housing to a support member;

a pair of clamps;

an axial shaft; and

one or more biasing members arranged to engage the shaft to return the jaws to one of a plurality of positions selected from a closed position and one or more open positions;

wherein the shaft is provided with one or more centering cam surfaces;

wherein the spindle comprises one or more stop surfaces, the or each stop surface being angularly displaced relative to the primary centering cam surface and extending in parallel with the spindle axis;

the or each biasing member being arranged to apply a force to the corresponding centering cam surface to center the jaws in one or more of the positions;

wherein the hinge comprises a primary biasing member and a primary spring arranged to extend the primary biasing member to engage the primary centering surface urging the jaws into the closed position; and

wherein the or each stop surface is arranged to engage with the primary biasing member to retain the shaft in a certain position.

Preferably, the biasing member is extended so as not to intersect the shaft axis.

The door is preferably a glass door, more preferably a frameless glass door. Movement of the clamp to the open or closed position moves the door to the open or closed position, respectively. The centering surfaces, and particularly the primary centering surface, act as cam surfaces when the biasing member rotates during opening or closing of the door.

The or each stop surface may be arranged to engage with the primary biasing member to retain the clamp of the hinge in the open position. Preferably, the hinge is held in the open position at right angles to the closed position.

Preferably, the or each stop surface is at right angles to the primary centring surface.

Preferably two parallel stop surfaces are provided. It is preferred that there are two open positions which are at right angles on either side of the closed position. In this arrangement, the door may be held in an open position at right angles on either side of the closed position. The door to which the hinge is attached can be held open in either direction unless a small closing force is applied to the door sufficient to overcome the force of the primary spring.

In the following description, the direction toward the biasing member or piston is referred to as proximal (proximal), and the direction away from the biasing member or piston toward the axis of rotation is referred to as distal (distal).

In a preferred embodiment, the shaft is arranged such that when the primary centring surface faces proximally towards the biasing member, the or each stop surface extends at right angles to the centring surface, the stop surface having a proximal edge facing the biasing member and a distal edge facing away from the biasing member.

In this position, the stop surface preferably extends from a position distal from the spindle axis to a position proximal to the spindle axis, or to a position on an axis on a diameter of the spindle parallel to the primary centering surface. In the latter arrangement, the or both proximal edges lie on the diameter of the shaft in the closed position, the proximal edges being orthogonal to the shaft diameter, the or each stop surface preferably extending distally of the shaft. In this arrangement, the hinge cannot angularly rotate at an angle beyond the open position due to the abutment between the biasing member and the stop surface. Rotation of the hinge toward the closed position is facilitated by a biasing member that contacts a proximal edge of the stop surface prior to engagement with the primary centering surface.

In an alternative embodiment, the proximal edge is located proximal to the diameter of the shaft. In this arrangement, the stop surface preferably extends proximally a sufficient distance to provide a restoring force to resist the hinge turning to the closed position. The distance between the proximal edge and the diameter (or axis of rotation) may be selected such that the biasing member provides a restoring force sufficient to allow a door fastened to the hinge to remain in an open position, but not so great as to make it difficult for a user to close the door. The length of the distance and thus the magnitude of the restoring force may depend on the width of the door, the weight of the door and the strength of the future user.

In a preferred embodiment, the primary centering cam surface is located proximally of the diameter of the spindle. This has several advantages. This facilitates the closing of the hinge. The extended length of the spring and other biasing member in use is reduced. This allows the use of stronger but less expensive springs. The volume of lubricant displaced during rotation of the shaft also decreases. This results in a longer working life of the oil.

Further cam surfaces may be provided at the proximal edge of the stop surface and the adjacent edge of the primary centering surface. The further cam surface may be rounded to promote smooth opening and closing of the hinge, reducing wear of the contact surfaces. This allows the use of a lesser grade of steel for the production of the shaft.

The clip may be adapted to securely engage the glass door panel. The glass door panel may be provided with holes to accommodate bolts passing through the clamps. Alternatively or additionally, the clamps may engage the glass door panel by friction or through the use of adhesives.

The hinge preferably includes a damping assembly for damping opening or closing movement of the hinge. Preferably, the biasing assembly includes a damping device to limit the rate of rotation of the hinge, particularly from the open position to the closed position. The damping assembly may also limit the rate of rotation from the partially open position to the fully open position.

In a first preferred embodiment, the hinge comprises a second biasing member and a second spring arranged to engage with the one or more second centering surfaces to urge the door into one of the two open positions.

The or each second centring surface may be a planar or cylindrical concave surface.

Alternatively, the second centering surface may comprise a cylindrical member that is parallel to and displaced from the shaft axis. The use of a cylindrical surface has the advantage that a smooth damping is achieved while only a small amount of wear occurs in the moving parts. The cylindrical member is preferably located within the circumference of the shaft.

In a second alternative preferred embodiment, the two hinge units comprise two biasing members, the first unit comprising a primary biasing member and the second unit comprising a secondary biasing member. The two units may comprise the lower and upper hinges of the door.

In a first preferred embodiment, the primary and secondary biasing members are preferably located in a cross bore, which is arranged to be spaced apart vertically, extending radially with respect to the shaft axis.

Preferably, the two biasing members are integral in a single unit and have a common axis of rotation.

Preferably, the two open positions of the hinge are at right angles to the closed position, while the two second centring surfaces are orthogonal to the main centring surface and diametrically opposite each other (diametrically oriented). That is, the second surfaces may be arranged facing in opposite directions, at right angles to the main centering surface.

The force of the primary spring is preferably greater than the force of the secondary spring. In this manner, the hinge moves to the closed position unless the door is in or adjacent to either of the two open positions. The hinge may thus comprise an over centre (over centre) arrangement in which the door moves into either a closed or open position when opened in either direction. The angular position of the respective centre points on the respective sides of the closed position is preferably close to the open position.

The primary spring may comprise a pair of concentric springs. The outer spring may be a stronger spring to provide the closing force for the hinge. The inner spring may be weaker than the outer spring and arranged to provide a closing force to the check valve when facing the biasing member. The check valve is further described below.

Each biasing member may comprise a piston mounted in a cylindrical bore for radial movement relative to the shaft.

The piston preferably comprises a hollow cylindrical member with a head arranged to engage a corresponding centring surface and with a cavity, a spring being located in the cavity within the cylindrical member to urge the piston out of the bore.

The shaft may be mounted in an upstanding channel in the housing which communicates with one or more channels in which the or each biasing member is located to allow circulation of hydraulic fluid or other oil during advancement of the hinge.

The spindle preferably includes an attachment member adapted to engage with a clamp. The end of the spindle may include a head arranged to engage with the socket of one of the clamps such that the spindle and the clamp are forced to rotate together.

According to a second aspect of the invention, a glass door hinge spindle comprises an axial shaft including an attachment for engaging with a door such that the spindle and the door are urged to rotate together in use;

wherein the shaft further comprises:

a primary centering surface parallel to the axis of the shaft, and two secondary centering surfaces orthogonal to the primary centering surface;

wherein the two second centering surfaces extend in diametrically opposed relationship about the axis of the shaft; and

wherein the shaft includes one or more stop surfaces angularly displaced from the primary centering surface at right angles to the primary centering surface and parallel to the shaft axis.

The or each stop surface is preferably at right angles to the main centring surface.

Preferably, the shaft further comprises an upper bearing surface and a lower bearing surface adapted to cooperate with the bearings within the hinge chain body.

In a preferred embodiment where the housing contains two biasing members, the primary centering surface is located below the secondary centering surface. Alternatively, the primary centering surface may be above the secondary surface.

The cavity in the housing containing the shaft and piston is preferably filled with a hydraulic fluid, such as lubricating oil.

Preferably, a cylindrical annulus is disposed between the primary and secondary centring surfaces, the surface of the cylindrical annulus being arranged to co-operate with the inner cylindrical surface of the hinge body to prevent deformation of the spindle in use. The annulus may also serve to prevent oil from flowing between the upper and lower portions of the bore.

The rotation of the spindle upon rotation of the hinge causes one piston to retract against the return force of the corresponding spring, but at the same time allows the other piston to expand. Likewise, as the hinge and door approach a closed or open position, the expansion of the piston under the influence of its spring action causes the door to continue to rotate until it is fully centered in the open or closed position.

The piston and the cylindrical sleeve may each provide a damping means. The piston and sleeve may be dimensioned as a sliding fit, but substantially prevent oil from flowing between their surfaces when the piston is compressed by rotation of the shaft. Oil can thus be forced through the constricting channel to dampen the motion of the hinge.

Grooves may be provided to allow oil to flow from the piston cavity to the cavity within the housing as the piston is compressed into the cylindrical sleeve.

The tank may include an adjustable valve to regulate the maximum flow of oil. Adjusting the valve allows the rate of closure of the hinge to be regulated so that in use the rotational movement of the hinge and door is damped.

The valve may comprise a needle valve and be threaded. This may control the dimensions of the passage leading from the piston and cylinder to the passage within the hinge housing.

Oil passing through the needle valve may be allowed to flow to the cavity between the spindle and the head of the piston.

Permanent magnets may be located in cavities in the and each sleeve or piston. The permanent magnet can be used to collect any metal particles formed by wear of the moving surfaces when the hinge is in use. This prevents further damage to the components of the hinge during use. For example, the spring seat may be magnetic.

In a preferred embodiment, the piston of the or each biasing member comprises a check valve arranged to allow oil to flow into the cavity as the piston and cylinder expand. In this manner, oil is circulated from the cavity of the piston into the cavity between the piston and the shaft and back into the piston cavity during the cycle of compression and expansion of the piston. During this cycle, the volume of the available cavity between the centering surface of the spindle and the piston increases as the piston is compressed and decreases as the piston expands into full engagement with the centering surface. This change in volume acts to pump oil through the check valve to circulate the oil during the opening and closing of the hinge and door. The circulation of oil helps to damp the hinge efficiently.

A primary piston and one or more slots may be provided to allow oil to flow from the cavity during the initial stages of compression of the piston.

In a preferred embodiment, the piston has a head and a cylindrical body dimensioned to be slidably received within the cylindrical bore of the sleeve and provided with one or more apertures at a predetermined axial distance from the head, the aperture or apertures being blocked by the sleeve after the body has been slid into the cylindrical sleeve by the predetermined distance. This arrangement allows oil to easily flow from the piston cavity until the piston has retracted to a predetermined extent, after which the flow of oil is impeded or impeded, thereby achieving a two-speed damping effect.

The primary check valve may be urged distally into the closed position by an internal spring of the primary biasing assembly. The length of the inner spring can be selected to provide the proper closing force to the valve. Preferably, the inner spring is longer than the outer spring.

A cutout may be provided at the distal end of the cylindrical body of the piston to allow oil to flow into the piston cavity when the piston is fully extended. At this stage, the check valve is engaging the centering surface of the spindle.

The cross-sectional area of the cutaway portion may increase from a position intermediate the head of the piston and the end of the shaft so that when the piston is extended to a fully extended position, the flow of oil between the sleeve and the bore in which the sleeve is mounted may increase. The cross-sectional shape of the cut-out portion may be selected to provide a suitable damping profile. For example, the cut-out portion may comprise a V-shaped or U-shaped slit. The cutaway portion may comprise a flat surface formed by removing a sector of the cylindrical sleeve. As a further alternative, parallel sided (parallel) slots may be utilized.

The hinge of the present invention has several advantages. By means of the biasing member, both the opening and closing of the hinge are damped by the circulation of oil. This prevents the door from slamming shut during opening and closing. Such slamming of the door may shatter the glass door or may cause injury. The degree of damping during door closing may be controlled by adjusting the valve in the second biasing member. The pumping action upon rotation of the shaft promotes the flow of oil within the biasing members.

In a preferred aspect of the present invention, the hinge further comprises:

a housing with a vertical bore;

an axial shaft mounted in the bore;

a closure device within the housing and adapted to engage the shaft to urge the hinge to a closed or centered position;

damping means within the housing and adapted to engage the shaft to damp movement of the hinge towards the closed position;

wherein the shaft has an upright axis and first and second centering cam surfaces arranged to urge closure means and damping means alternately away from the axis when the housing is rotated away from or towards a closed position, respectively, relative to the shaft;

wherein the closing means comprises a pusher head with at least one closing contact surface and a spring arranged to urge the contact surface into engagement with the first centring surface;

wherein the damping device comprises a working fluid and a piston comprising a piston head and a sleeve slidably mounted within a cylinder, a spring located within the cylinder, the piston having a projection with a damping contact surface urged by the spring into engagement with the second centering surface of the shaft; the damping piston includes a check valve;

wherein the closure means and the damping means extend radially from the axis of the shaft in opposite directions;

wherein the inner surface of the damping piston, the sleeve and the cylindrical barrel form a first chamber, and the outer surface of the damping piston head, the bore and the shaft form a second chamber for the working fluid;

the working fluid disposed in the second chamber passes through a check valve in the damping piston as the damping piston moves toward the shaft axis in use, and backflow through the check valve is blocked as the damping piston moves away from the shaft axis.

In a particularly preferred embodiment, an adjustable valve is located in the housing;

a first conduit communicates between the first chamber and the adjustable valve;

a second conduit communicates between the second chamber and the adjustable valve;

adjustment of the valve thus controls the flow of working fluid from the first chamber to the second chamber to dampen movement of the hinge to a closed or centered position.

The use of a single adjustable valve is preferred. However, two or more adjustable valves may be used if desired.

The hinge according to embodiments of the present invention has several advantages. The use of two independent closure and damping devices allows each to be produced in a simple yet robust construction such that the closure force and damping profile can be selected to suit any particular application. For example, a more robust damping device may be used for heavy or large doors that tend to slam shut during use.

The location of the damping means on the opposite side of the closure device to the spindle may provide a more balanced configuration compared to a hinge where both the closure piston and the damping piston are on the same side of the spindle axis. Wear of the bearings is reduced so that the cam surfaces are less likely to be misaligned with continued use. This is particularly important in the case of relatively small second or intermediate cam surfaces (if present as described below) because if the spindles are not accurately aligned, the edges of the cam surfaces may wear out.

The damping device contains a circuit of working fluid which extends from the chamber in which the spring is located to the adjustable valve and from the adjustable valve to a chamber located at the outer front surface of the damping piston which engages with the cam or centering surface of the spindle. The moving parts are thus maintained in a good lubrication condition.

A single adjustable valve may be located outside the housing, making adjustment simple and convenient.

The closure means is located in a separate chamber within the housing and may be filled with oil or other fluid, but this is not essential. One or more apertures may be provided to allow the working fluid to circulate into the piston as it telescopes in use. The slot may be dimensioned to inhibit fluid flow, providing additional damping to the hinge. Alternatively, the slit may be large enough to allow free flow.

The first and second centering cam surfaces may have similar or different configurations. In a preferred embodiment, the radial cross-section of the surfaces is approximately semi-circular. Preferably, the planar portions extend forwardly of the axis of the shaft so that the axis passes through the shaft but not through the space in front of the planar surface.

A second stop surface may be provided at right angles to the planar surfaces. This allows the hinge to stop in the open position, for example at 90 ° to the centering position of the door closed. This arrangement is not feasible if the closure member extends beyond the axis of the spindle in this centered position.

The closure member may comprise a piston slidably movable within a cylinder, the piston comprising a piston head and a sleeve, preferably a cylindrical sleeve. The piston head may have a protrusion with one or more contact surfaces. A spring may be located within the sleeve and arranged to engage the rear surface of the piston head to urge the contact surface or surfaces into engagement with the centring surface of the shaft.

In a preferred embodiment, the shaft includes an axially extending member with a closing cam surface and one or more damping cam surfaces disposed axially spaced from the closing cam surface;

an obstruction is provided between the closing cam surface and the damping cam surface that extends toward the surface of the aperture to substantially prevent fluid flow between the closing and damping cam surfaces during use.

The flow of fluid is preferably prevented to such an extent that increasing fluid pressure on one side of the barrier does not result in increased fluid pressure on the other side of the barrier sufficient to reduce the closing force exerted by the piston of the closure member.

However, sufficient clearance may be provided between the obstruction and the bore to allow the fluid to lubricate.

The obstruction may comprise a cylindrical ring extending radially from the axis of rotation to a position adjacent the surface of the bore.

The closing surface or cam surface may be parallel to the contact surface of the piston in the fully extended position of the piston.

The diameter or width of the closing or centering surface is preferably less than the diameter of the cylindrical annulus or other obstruction. The diameter of the closing cam surface or centering surface may be 70% to 98%, preferably 80% to 98%, more preferably 85% to 95% of the diameter of the annulus. The use of a smaller diameter or width reduces the compression of the closing spring or springs. Thereby reducing friction and wear of the closing surface.

One or more second surfaces may be provided. They may be angled at right angles to the first surface. These surfaces hold the hinge in an open position, for example 90 ° from a closed or centered position. The diameter or width of the closing or centering surface, which is the distance between the second surfaces, may also be reduced to prevent wear of the moving parts during use.

One or more intermediate surfaces may be provided between the first and second surfaces, which are positioned at an angle intermediate the first and second surfaces. These intermediate surfaces may be planar or convex and may serve to hinder or prevent the hinge from closing at some intermediate angle. In this arrangement, the door is prevented from accidentally slamming shut. The intermediate surfaces may be at an angle of 30 °, 45 ° or 60 ° to the primary closing centering cam surface. The engagement of the biasing member with the intermediate surface may slow the rate at which the door rotates, or may allow the door to stop at the intermediate angle.

The body of the damping piston may comprise a sleeve with one or more cut-outs providing one or more passages extending along the exterior of the sleeve to a position at the end of the sleeve which communicates with the internal cavity providing different damping depending on the extension of the damping piston. The cross-sectional area of the passage or passages may vary along the length of the sleeve, for example increasing away from the shaft axis, so as to provide a smaller cross-sectional area for fluid flow as the sleeve and piston head are compressed away from the shaft axis. Fluid flow through the passage or passages is prevented when the damping piston is near a fully compressed position.

The contact surface of the protrusion may be concave or cylindrical to provide a shallow depression. This serves to prevent the cam surface from attaching to the shaft. The cam surface may become uneven with continued use. The cam surface may be planar or curved. The use of concave or cylindrical surfaces may be advantageous to ensure that the surfaces are smooth and in unobstructed contact with each other as the hinge rotates. Excessive compression of the spring is avoided and friction between the moving parts is reduced. The use of a concave region on the plunger pusher provides several advantages. The concavity helps to dampen the door on which the hinge is mounted when the door is closed. Good contact with the shaft is ensured if the central contact surface of the shaft has become rough or uneven due to wear. Furthermore, the concave surface is used to release the compression of the closing spring. This reduces friction when the door is opened to 75 ° to 85 ° when the hinge is opened. The recessed region may provide a recess for any residue that may occur, for example, during prolonged use to accumulate.

The contact surface may comprise a central portion located axially with respect to the axis of the shaft and two outer portions, the central portion having a greater or lesser length from the piston head than the outer portions.

In a first embodiment, the intermediate portion is longer and extends further towards the axis of rotation, so that the contact surface is substantially convex.

In an alternative embodiment, the middle portion is shorter such that the contact surface is substantially concave or inwardly curved.

The middle and outer portions may be individually curved or planar and may form continuous or intermittent axially symmetric contact surfaces. For example, smooth concave or convex surfaces may be provided. Or may be provided with a stepped configuration.

Selection of an appropriate contact surface distribution and configuration of the centering cam surface controls the closing force and the damping force as the hinge rotates in use.

In alternative embodiments, the contact surface may be convex or extend outwardly in a cylindrical fashion.

The convex or outwardly extending surface may help maintain the spring in a compressed state, enabling the door to withstand high winds without being blown open.

Drawings

The invention is further described, by way of non-limiting example, with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a first hinge according to the present invention;

FIG. 2 is an exploded view showing the components of the hinge;

FIG. 3 is a cross-sectional view of the hinge in an open position;

FIG. 4 is a cross-sectional view of several of the hinges in various positions;

FIG. 5 contains a view of a plurality of such spindles;

FIG. 6 contains a cross-sectional view of some alternative spindle;

FIG. 7 contains a view of a plurality of such spindles;

FIG. 8 is a cross-sectional view of a further hinge unit;

FIG. 9 is a cross-sectional view of the unit;

FIG. 10 contains a view of a plurality of such spindles;

FIG. 11 is an exploded view of a further hinge unit;

FIG. 12 is a cross-sectional view of the unit;

FIG. 13 contains a view of a plurality of such spindles;

FIG. 14 contains a cross-sectional view of a plurality of further spindles;

figure 15 is a view of a piston comprising a plurality of such hinges according to the invention;

FIG. 16 is a perspective view of an alternative hinge according to the present invention;

FIG. 17 is a cross-sectional view of the hinge shown in FIG. 16;

FIG. 18 is a perspective view showing the damping piston;

FIG. 19 is a perspective view showing the closing piston;

FIG. 20 is a perspective view of the spindle;

figures 21 to 29 show different configurations of the piston and pusher head.

Detailed Description

The following description of the embodiments uses the same reference numerals to refer to the same components in the various embodiments.

Fig. 1 shows a perspective view of a hinge according to the invention. The housing (1) is mounted on a support table (2) with vertical members (3) having apertures (4) for bolts, screws or other fixing components (not shown).

A pair of clamps (5) are pivotally connected to the housing (1). The holder (5) is provided with an aperture dimensioned to receive the glass screen.

Fig. 2 is an exploded view of a first embodiment of the present invention. Figure 3 shows a cross-sectional view of the hinge.

The rotary shaft (6) is accommodated in an upright hole (7) of the housing (1). The shaft is mounted on bearings (8, 9) sealed by a washer (10) and a threaded sealing member (43) to allow the shaft to rotate in use.

The spindle is substantially elongate and includes a cut-out portion defining a centering surface. The primary centering surface (11) is located below the axis of rotation. Two diametrically opposed second centring surfaces (12) are placed at right angles to and above the main centring surface (11). A cylindrical annulus is located between the first and second centering surfaces. The surface of the ring cooperates with the inner cylindrical surface of the housing to maintain alignment of the shaft and transfer force from the spring to the housing. This serves to prevent the shaft from deforming due to forces exerted by the piston during use.

The square head (13) enables the spindle to be connected to a cooperatively shaped notch (23) in one of the clamp members so as to force the spindle and clamp members to rotate together in use.

Two biasing assemblies are located in vertically spaced cross bores in the housing (1) which are arranged radially relative to the axis of the shaft (6). The primary biasing assembly is located in the lower bore (14) and the secondary biasing assembly is located in the upper bore (15).

As shown in fig. 3, the primary biasing assembly comprises a cylindrical piston (16) with a head (17) and an internal cavity (18). The middle part of the head (17) is provided with a slit (19) which is communicated with the cavity (18). The slot (19) is dimensioned to control the rate of oil flow when the hinge is in use. A pair of springs (25, 25a) are loaded on the spring seat (24). The distal end of the spring remote from the spindle is received in a cylindrical sleeve (26). The pair of springs (25, 25a) applies an axial force to urge the piston (16) towards the centering surface (11) of the shaft. The pair of springs (25, 25a) are selected to provide a uniform extension force over their range of operation.

As shown in fig. 3, the second biasing assembly includes a second piston (27) with a hollow cylindrical body and a head (28) and defining an internal cavity (29). A disk (30) with a central aperture (31) cooperates with a check valve member (32). The disc (30) is sealed by a gasket (33). Apertures (31) in the disc (30) are used to regulate the flow of oil through apertures (35) in the head of the piston. A primary helical outer spring (36) engages the spring seat (20) to urge the piston (27) into engagement with the rotatable shaft (6). The length of the second internal spring (36a) is selected to urge the valve member (32) against the valve seat (20) and the disc (30) to close the valve.

As with the primary biasing member, the sleeve (38) is provided with a cylindrical bore to receive a cylindrical piston plug (27) allowing sliding movement of the piston in a radial direction relative to the axis of the spindle.

The upper second piston device serves to damp the closing movement of the hinge. The sleeve (38) is provided with a cylindrical bore to receive the piston (27). The piston (27) has a head (28) and an internal cavity (29). A cutaway portion (21) is provided at the distal end of the cylindrical piston plug body remote from the head and spindle. A spring (36) urges the piston toward the axis of rotation. As shown in fig. 3, when rotation of the spindle causes the piston to retract into the sleeve, the check valve (32) closes the slit (31) so that oil is driven from the distal end of the piston through the cutout (21) and annular groove (45), past the needle valve (47), allowing oil to circulate into the cavity adjacent the spindle, particularly the cavity formed by the centering surface (12). Adjusting the needle valve controls the maximum flow rate of the oil to produce the desired damping effect appropriate to the weight of the glass door or other factors. Rotation of the spindle and centering surface (12) allows the piston to extend while forcing oil through the check valve into the piston cavity for another cycle.

As shown in fig. 15, the piston (27) of the second biasing member has a cut-out (21) on the exterior of the cylindrical body of the piston. The cut-out communicates with the slot (39) and the aperture (22) as the piston extends toward the axis of rotation such that the head (28) engages the second centering surface (12). In this position, oil can flow from the inner cavity (29) of the piston (27) through the cutout (21), the groove (39), the slit (22) and into the cavity (40) surrounding the head of the piston. When the piston (27) is retracted, flow through the cutaway portion is inhibited and then completely interrupted.

During the centring of the spindle in the closed position, the oil stored in the cavity (40) of the spindle passes through the slit (19) into the internal cavity (18) of the piston, due to the expansion of the piston (16) caused by the action of the spring (25). During the return stroke, as the piston is compressed into the shaft (26), oil is returned to the cavity (40), and as the shaft rotates during use, its volume increases.

Fig. 4 and 5 further illustrate the construction and function of the hinge according to the invention. FIG. 4 includes cross-sectional views illustrating various stages of operation of the hinge unit. The construction of this hinge is shown in more detail in figure 5. The same reference numerals are used to denote the components shown in figures 1 to 3.

The spindle shown in fig. 5 comprises a square head (13) which extends from a shaft with an axis (53). The second centring surfaces (12) are parallel to each other and extend on opposite sides of the axis (53). The second centering surface is provided with a tapered or pointed end to facilitate engagement with the head of the piston (27), as shown in cross-section a-a of fig. 4.

The primary centring surface (11) is substantially planar and is displaced in the vicinity of the piston (16) so that the piston (16) cannot extend beyond the line of rotation (53), the maximum extent of which is not beyond the line of rotation (53). The rear surface (50) is cylindrical to cooperate with a matching cylindrical bore (7) of the housing (1). A cylindrical annulus (54) forms an additional bearing surface between the two centering surfaces.

In the embodiment shown in section B-B of fig. 5, the primary centering surface (11) is planar and extends in parallel with the axis (53). The two stop surfaces (51) are also planar and extend at right angles to a main centering surface (11) which is parallel to the axis (53). A curved cam surface (52) extends between a leading proximal edge (55) of the stop surface (51) and an adjacent edge (57) of the primary centering surface (11). The cam surface (52) allows the hinge unit to operate more smoothly and reduces wear on the edges (55, 57). The stop surface (51) extends between a proximal edge (55) and a distal edge (56), as shown in section B-B of fig. 5.

In the embodiment shown, the spindle is provided with two opposing stop surfaces (51). In an alternative embodiment, only a single stop surface (51) may be employed for a hinge unit adapted to open in one direction.

Section B "-B" of fig. 5 shows an alternative configuration in which the main centring surface (57) is concave and substantially cylindrical in cross-section. The concave surface (59) may cooperate with a mating circular piston head. Or a piston head in the shape of a flat disc may be used.

Fig. 4 illustrates the function of the hinge. The hinge is shown slightly open above the cross-section B-B. In this position, the piston is pushed proximally and the spring (25) is partially compressed. As the rotation continues, the door reaches a fully open position, as shown in the middle cross-sectional view. In this position, the stop surface (51) is aligned with the head (17) of the piston (16) and the spring (25) is fully compressed. The planar stop surface (51) aligned with the head of the piston prevents the spindle from rotating so that the user can release to leave the door in the open position. As shown in the lower cross-sectional view, section B-B, the door may be slightly displaced so that it opens more fully. However, the cooperation of the piston head (17) and the cylindrical rear surface (50) of the shaft has the following effects: the door is free to rotate without being urged to either the open or closed position. On the other hand, moving to the closed position as shown in the upper cross-sectional view allows the piston to expand and urge the door toward the fully closed position with the piston face (17) aligned with the centering surface (11) in this position. In this position, the door will stop.

In a first embodiment, the proximal edge (55) of the stop surface (51) is located on a diameter parallel to the main centering surface (11). In this arrangement, further opening of the door beyond the vertical position as shown below the cross-sectional view B-B requires the application of force to further compress the spring (25). However, no additional force need be applied to close the door to the position of the upper cross-sectional view.

In an alternative embodiment, proximal edge (55) is located proximal to axis (53). A little force is required in this arrangement to displace the door from the right-angled open position to initiate the closing movement.

Doors including hinges according to embodiments of the present invention require manual force to open from a closed position to a right angle position. A little additional force may be required to open the door beyond this right angle position, but no further compression of the spring occurs due to the cylindrical shape of the distal surface (50) of the spindle. Thus, the door is free to move beyond the right angle position, but will automatically close when moving from the right angle position to the closed position.

Fig. 6 and 7 illustrate an alternative embodiment where the second centering surface (60) of the spindle is cylindrical and offset from the spindle axis (53). Preferably, the cylindrical surface (60) is located around the circumference of the main shaft body to form a continuous surface with the annulus (54). In this embodiment, when the shaft is rotated, the second centering surface (60) precesses, resulting in compression or release of the second spring (36). The centering surface may be tangential to the spindle surface. This device is less prone to mechanical wear than the devices shown in figures 4 and 5. Since the flow rate of the oil being displaced is smaller, smoother damping can be provided.

Figures 8 to 14 illustrate an embodiment of the invention in which the hinge is divided into two parts, the first part comprising the primary centring surface and the second part comprising the second damping means.

Fig. 8 to 10 show the main centering unit. This may be located, for example, at the bottom of the door. The bottom plate (61) is screwed into the housing (62) with a pair of cylindrical holes (63) by a thread. A pair of pistons (64) are located in the bores and are urged distally by an axial spring (65). A rotating shaft (66) mounted in bearings (67, 68) is disposed in an upright bore (69) in the housing (62). The construction of the spindle is shown in detail in fig. 10. The spindle (66) carries a square head (79, 70) having a single major centring surface (71) extending proximally from the axis (72) so that in use the piston (not shown) cannot extend as far as the axis. The stop surface (73) has a proximal edge (75) and a distal edge (76) connected by a cam surface (74) to an adjacent edge (77) of the primary centering surface (71). The primary centering surface (71) is cylindrically concave, as shown in section B-B of FIG. 10.

In an alternative embodiment, the primary centering surface, as shown in section B-B of FIG. 10, may be planar (78).

Fig. 11 to 13 show a second damping unit according to the present invention. This may be located, for example, in the middle or upper part of the door to provide efficient damping. The unit is similar to that shown in figures 1 and 3, although only a single piston (80) is located within the housing (81). The construction of the spindle (82) is shown in more detail in fig. 13. Opposing planar centering surfaces (83) are disposed on either side of the shaft axis. The area between the centering surfaces has a tapered or pointed protrusion (84) to provide a smooth wear surface for contacting the piston head (85).

Fig. 14 shows an alternative spindle having a cylindrical cam surface (90) disposed (63) between bearing rings (91, 92). The cylindrical cam surface (90) is offset from the shaft axis to lie adjacent the shaft circumference. The rotation of the rotating shaft provides a smooth cylindrical surface (90) which can smoothly exert a damping force when the door is closed or opened.

Figure 15 shows the configuration of the piston of the damping device as described with reference to figure 2. One or more, preferably two, cut-out portions (21) comprise flat or planar portions removed from the proximal end of the cylindrical sleeve (27). Concave portions may be used.

Fig. 16 shows a perspective view of an alternative hinge according to the present invention. A pair of clamps (101) mounted on the housing (103) form slots (104) in which glass door panels (not shown) may engage.

The base plate (102) serves as a support member arranged to be fastened to a floor or ground (not shown). As shown in fig. 6, the stand (105) may be fastened within the bottom plate (102) so that the door is easily assembled.

Figure 17 shows a cross-sectional view of the hinge. A shaft (106) extends axially upright within the hinge body. The shaft (106) is received in a blind bore (111) in the housing (103) with a closed upper end (112). A gasket (113) seals the shaft and bore against leakage of working fluid during use. A square shaped retaining lug (107) at the lower end of the spindle is received in a socket shaped to mate with the abutment (105) to prevent rotation of the spindle in use. Bearings (109, 110) allow the housing (103) to rotate about the shaft axis.

The closure device (114) is mounted in a generally cylindrical chamber (115) in the housing (103) which extends radially from the bore (111). The chamber (115) is closed by a cylindrical barrel (116) with a threaded end cap. A closing piston comprising a cylindrical sleeve (117) and a piston head (118) is slidably received within the cylindrical barrel (116). The piston head (118) carries a projection (119) which extends radially from the chamber (115) through the aperture (120) into the bore (111). A pair of coil springs (121, 122) extend between the end cap of the cylindrical barrel (116) and the rear surface of the piston head (118) to urge the contact surface (125) of the projection (119) into engagement with the shaft (160).

A cylindrical annulus (131) extends radially from the axis of rotation to a circumference adjacent the inner surface of the bore (111). The clearance between the ring (131) and the bore (111) is sufficient to allow the passage of lubricating fluid, but small enough to prevent fluid pressure from passing from one side of the ring to the other during door opening or closing in normal use.

The cavity between the shaft and the bore is thus divided into an upper and a lower part. The lower chamber (123) communicates through the aperture (120) with a forward portion of the chamber (115) radially inward of the piston head (118). The aperture (124) allows working fluid to flow through the piston head when the piston head is moved radially inward or outward in use. The upper chamber (130) similarly communicates with a cylindrical damping chamber in which a damping piston is located, as described below.

The contact surface (125) of the projection (119) is received in a socket defined by a lower surface of the ring (131), an upper surface of the other lower ring (127) and a substantially planar cam surface (126) of the shaft (106). The cam surface (126) extends parallel to the contact surface (125) of the projection (119) and radially outwardly towards the shaft axis so that the contact surface does not extend beyond the axis during use.

As shown in fig. 20, the planar stop surface (128) extends upright at right angles to the cam surface (126). Preferably two stop surfaces are provided. These are used to keep the door open during use.

The door is opened to rotate the hinge chain body relative to the rotating shaft. Rotation from the closed centered position causes the projection (119) to rotate relative to the cam surface (126), urging the projection and piston radially outward to compress the spring (121, 122). During this piston movement, working fluid in the chamber (115) flows radially inward through an aperture (124) in the piston head into a cavity in front of the piston head between the bore and the rotating shaft.

When the door is opened to 90 deg., the hinge will remain open due to the end of the projection engaging a stop surface (128) at right angles. Slight pressure on the door is sufficient to release the hinge, after which the springs urge the housing to rotate relative to the pivot shaft, returning the door to a closed centered position without further manual effort.

As shown in fig. 20, one or more intermediate stop surfaces (153) may be provided. The intermediate stop surfaces, which are located at an angle between the main cam surface (126) and the right angled stop surface (128), allow the damping force to be exerted if the door is quickly closed.

The width or diameter of the planar cam surface (126) is less than the diameter of the ring (127) or (131). Preferably, the diameter of each cam surface is smaller than the diameter of the ring (127), (131) or (149) to reduce wear of the components during use. The diameter of the surface (126) may be 70% to 98%, preferably 80% to 98%, more preferably 85% to 95% of the diameter of the annulus (127). The reduced diameter reduces the distance between the second stop surfaces (128), thereby reducing the degree to which the closing springs (121, 122) are compressed in the fully open position of the hinge. The closing force exerted by the closing piston is reduced, so that the friction and long-term wear between the contact surface (125) and the surface (128) is also reduced.

The damping device is located in a damping chamber (129) extending radially in the opposite direction to the closing device (114). The damping chamber may be axially offset relative to the closure chamber.

A piston comprising a piston head (132) and a cylindrical sleeve (133) is mounted for slidable movement in a cylindrical barrel (134). The one-way check valve includes a seat (135) and a valve stop (136) located within the piston. A slot (137) in the valve head allows working fluid to pass between a first chamber (138) in the piston and a second chamber (139) radially towards the piston head (132). Fluid may flow from the second chamber (139) to the first chamber (138) through the valves (135, 136); but flow from the first chamber (138) to the second chamber (139) is blocked by the closing of the valves (135, 136).

A projection (144) with a radially inwardly facing contact surface (145) extends from the piston head (132). The contact surface (145) may be planar, slightly concave or with a central cylindrical depression and is arranged to engage one of two planar cam surfaces (146) on the shaft. The cam surface (146) extends parallel to the opposite side of the shaft axis and at right angles to the closing cam surface (126) of the shaft. The stop surface (147) extends at right angles to the cam surface (146). The second stop surface (148) extends at some intermediate angle between the cam surface (146) and the stop surface (147), for example 60 °, 45 ° or 30 ° to the cam surfaces.

In alternative embodiments, the contact surface may be convex or with an outward cylindrical recess.

The upper ring (149) together with the ring (131) and the cam surfaces (146) serve to define a socket (150) to receive the protrusion (144) when the hinge is rotated. When the door is opened or closed, the hinge housing rotates about the axis of rotation, causing the closing piston and the damping piston to be compressed or expanded, depending on the orientation of the respective cam surfaces relative to the projections of the pistons. When the closing piston is compressed, the damping piston expands to flow working fluid radially outward from chamber (139) into chamber (138) where the fluid contacts the spring, so that fluid is largely within the piston.

The cylinder (134) is provided with an aperture (143) communicating with a first conduit (141) extending from the chamber (129) to a first side of an adjustable screw valve (140) located in a bore external to the housing (103). A second conduit (142) extends from a second side of the adjustable valve (140) to a second chamber (139). When the solenoid valve is opened, working fluid may flow from the first chamber (138) to the second chamber. The valve dampens the flow of fluid due to partial closure, damping the movement of the piston and preventing rapid door closing.

When the door is closed or released by a human hand to allow closing (the reason for closing being the force of the springs (121, 122)), the damping piston is compressed. The force of the spring (151) is weaker than the force of the springs (121, 122). The spring (151) acts to dampen the opening and closing motion of the hinge by compressing the spring, acting to dampen the opening of the hinge. Further damping may be provided by the friction of the spring during opening. A pair of springs may be provided, the weaker being longer, to maintain the damping force throughout the movement of the piston.

The fluid pressure in the first chamber (138) increases and the one-way valves (135, 136) are also closed, preventing fluid from passing through the valves. As the pressure increases, the fluid is forced through apertures (143) in the cylinder and into the conduit (141) within the housing (103). Fluid passes through conduit (141) to the first side of the solenoid valve and into conduit (142) which returns the fluid to the damping chamber (129) of the damping device, radially inward toward the piston head, near the axis of rotation, as shown in fig. 17. Adjusting the slit of the screw valve limits the maximum rate of fluid flow through the valve such that increased pressure within the chamber (138) inhibits closing or centering movement of the hinge.

The outer surface of the sleeve (133) is provided with a cut-out (152) to form a passage allowing fluid to flow from the first chamber (138) to the slit (143) and the valve (140). The cross-sectional area of the passage may vary along the axial length of the sleeve and decrease radially inwardly relative to the shaft so as to provide a smaller cross-sectional area for fluid flow as the sleeve (133) and piston head are compressed and moved away from the shaft.

When the damping piston reaches the fully compressed position, fluid flow may be inhibited and may be prevented. In this manner, the damping force is increased as the hinge approaches the fully closed or centered position. When the fully closed or centered position is reached, the closing action of the hinge is reduced and may be stopped.

The increase in fluid pressure in the second chamber (139) is due to the pressure of the spring (151) and piston head (132) when the hinge is opened. Since the annulus (131) is adjacent the inner surface of the bore (111), fluid is prevented from flowing into the operating chamber of the closure.

In this manner, fluid is retained in the second chamber (139) and flows through the check valve (135, 136). This ensures that an appropriate amount of fluid generates sufficient pressure in the first chamber (138) during the return stroke to force fluid through the circuit defined by the adjustable valve (140) and the conduits (141, 142).

Figures 21 to 28 show different configurations of a biasing member comprising a piston with a pusher head.

Fig. 21 shows a piston including a biasing member with a piston head (180) having a rearwardly or proximally extending cylindrical sleeve (181) and a rearward end (182). The rear end is open to accommodate a spring (not shown). A protrusion (183) offset from the axis of the cylindrical sleeve (181) extends forwardly from the piston head (180) and has a flat or planar contact surface (184) arranged to engage a centering cam surface (not shown) of the shaft. In use, the piston moves radially inwardly or outwardly relative to the axis of the shaft due to engagement with the cam surface against the restoring force provided by the spring.

Fig. 22 shows an alternative piston with a contact surface having a cylindrical concave axial portion (185) located between a pair of flat or planar outer portions (186). The cylindrical concave central portion (185) serves to reduce friction due to compression of a spring (not shown) to reduce wear on moving parts during continued use.

Fig. 23 shows a further alternative embodiment, in which a flat or planar middle portion (187) is located between two shoulders (189) and a flat or planar outer portion (188). In this arrangement, the middle portion (187) extends from the piston head (190) a shorter distance than the outer portion (188) to reduce the friction of the spring at maximum compression.

Fig. 24 shows a further alternative embodiment in which a cylindrical convex middle portion (191) extends from the piston head (193) a greater distance than two flat or planar outer portions (192).

Fig. 25 shows a further embodiment. The planar axial middle portion (194) is located between the two shoulders (195) and the planar outer portion (196). A middle portion (194) of the contact surface extends from the piston head (197) a greater distance than the outer portions (196).

Fig. 26 shows a further embodiment in which a continuous cylindrical convex contact surface (198) extends across the entire width of the projection (199).

Fig. 27 shows a piston similar to that shown in fig. 21, in which a V-shaped slit (200) embedded in a sleeve (203) extends from an upper intermediate position (201) of the sleeve to a rearward open end (202). The cross-sectional area of the slot (200) increases from the forward point (201) towards the end (202) so that the flow of oil increases as the piston moves forward towards the axis of rotation in the axial bore (not shown).

Figure 28 shows a further embodiment in which the sleeve (204) has a flat sector (205) removed therefrom to provide an opening extending from a point (206) at the front of the sleeve to the rear end (207) of the sleeve, the cross-sectional area of the slot increasing from this point (206) rearwardly towards the end (207) of the sleeve, allowing more oil to flow therethrough as the piston extends towards the axis of rotation in use.

Fig. 29 shows another embodiment, in which the sleeve (208) is provided with a V-shaped slit (209) extending from some intermediate portion to the opening at the rear end of the piston. The piston head (210) has a protrusion (211) that extends forward to form a contact surface (212). The contact surface (212) has a central, axially planar portion (213) with an inclined portion (214) on either side thereof extending to an outer planar portion (215) formed on the outer edge of the projection (211). In this way, the contact surfaces are at a maximum distance from the axial extension of the piston and the radial extension of the counter shaft (not shown) and are formed with shorter projections (215) on the respective outer sides.

Claims (28)

1. A door hinge with an in-door stop device, comprising:

a housing;

a mount connecting the housing to a support member;

a pair of clamps;

an axial shaft;

one or more biasing members arranged to engage the shaft to return the jaws to one of a plurality of positions selected from a closed position and one or more open positions;

wherein the shaft has one or more centering surfaces; and one or more stop surfaces angularly displaced relative to the primary centering surface and extending parallel to the shaft axis;

the or each biasing member being arranged to apply a force to the corresponding centring surface to centre the clamps in one or more of the positions;

wherein the hinge comprises a primary biasing member and a primary spring arranged to extend the primary biasing member to engage the primary centering surface urging the jaws into the closed position; and

wherein the or each stop surface is arranged to engage with the primary biasing member; so that the spindle is held in a certain position.

2. A hinge as claimed in claim 1, wherein the or each stop surface is at right angles to the primary centring surface, and wherein the or each stop surface is arranged to engage with the primary biasing member to retain the hinge in an open position at right angles to a closed position.

3. A hinge as claimed in any preceding claim wherein there are two parallel stop surfaces.

4. A hinge as claimed in any preceding claim wherein the axis of rotation is arranged such that when the primary centring surface faces the biasing member, the or each stop surface extends at right angles to the centring surface, the or each stop surface having a proximal edge facing towards the biasing member and a distal edge facing away from the biasing member.

5. A hinge as claimed in any preceding claim wherein the primary centring surface is located proximal to the diameter of the pivot.

6. A hinge as claimed in claim 4 or 5, wherein the stop surface extends relative to the biasing member from a position distal to the shaft axis to a position proximal to the shaft axis.

7. The hinge of claim 6, wherein the stop surface extends from a location distal to the spindle axis to a location on a diameter of the spindle that extends parallel to the primary centering surface.

8. A hinge as defined in claim 6 or 7, wherein the distal edge is transverse to the pivot diameter.

9. The hinge of any of claims 4-8, wherein the distal edge is located proximate a diameter of the shaft.

10. A hinge as claimed in claims 4 to 9, wherein cam surfaces are provided at the proximal edge of the stop surface and at the adjacent edge of the primary centring surface.

11. A hinge as claimed in any preceding claim, comprising;

a second biasing member and a second spring arranged to engage one of the two second centering surfaces to urge the door into one of the two open positions.

12. A hinge as defined in claim 11, wherein the primary and secondary biasing members are located in a cross bore that is arranged to be spaced apart vertically, extending radially relative to the shaft axis.

13. The hinge of any preceding claim, further comprising

A housing with a vertical bore;

an axial shaft mounted in the bore;

a closure device within the housing and adapted to engage the shaft to urge the hinge to a closed or centered position;

damping means within the housing and adapted to engage the shaft to damp movement of the hinge towards the closed position;

wherein the shaft has an upright axis and first and second centering cam surfaces arranged to urge the closure means and damping means alternately away from the axis when the housing is rotated away from or towards a closed position, respectively, relative to the shaft;

wherein the closing means comprises a pusher head with at least one closing contact surface and a spring arranged to urge the contact surface into engagement with the first centring surface;

wherein the damping device comprises a working fluid and a piston comprising a piston head and a sleeve slidably mounted within a cylindrical barrel, a spring located within the cylindrical barrel, the piston having a projection with a damping contact surface urged by the spring into engagement with the second centering surface of the shaft; the damping piston includes a check valve;

wherein the closure means and the damping means extend radially from the shaft axis in opposite directions;

wherein the inner surface of the damping piston, the sleeve and the cylindrical barrel form a first chamber, and the outer surface of the damping piston head, the bore and the shaft form a second chamber for the working fluid;

the working fluid disposed in the second chamber passes through a check valve in the damping piston as the damping piston moves toward the shaft axis in use, and backflow through the check valve is blocked as the damping piston moves away from the shaft axis.

14. A hinge as claimed in any preceding claim, wherein each biasing member comprises a piston mounted in a cylindrical bore for radial movement relative to the axis of rotation.

15. A hinge as defined in claim 14, wherein the piston comprises a hollow cylindrical body with a head arranged to engage a corresponding centering surface and with a cavity, a spring being located within the cavity to urge the piston out of the bore.

16. A hinge as claimed in any preceding claim wherein the shaft is mounted in an upstanding channel in the housing, the channel communicating with a passage, the passage communicating with a bore, the biasing members being located within the bore to allow circulation of hydraulic fluid or other oil during advancement of the hinge.

17. The hinge of any of claims 11-16, wherein the configuration of the second centering surface is selected from the group consisting of: cylindrical, concave, or convex, and offset from the spindle axis.

18. A hinge as claimed in claim 11 or any claim dependent on claim 16, wherein a groove is provided to allow oil to flow from the piston cavity to the cavity in the housing when the piston is compressed into the sleeve, and an adjustable valve is included to regulate the maximum flow of oil.

19. A hinge as claimed in claim 11 or any claim dependent on claim 16, wherein the piston of the biasing element comprises a check valve arranged to allow oil to flow into the cavity as the piston and cylinder expand.

20. The hinge of claim 18, wherein the biasing element comprises an inner spring and an outer spring, the outer spring engaging the piston to urge the piston toward the axis of rotation, the inner spring engaging the check valve to urge the valve into the closed position.

21. A hinge as claimed in claim 14 or any claim dependent on claim 18, wherein the piston has a head and a cylindrical body dimensioned to be slidably received within the cylindrical bore of the sleeve and provided with one or more apertures at a predetermined axial distance from the head, the aperture or apertures being blocked by the sleeve after the body has been slid into the cylindrical sleeve by the predetermined distance.

22. The hinge of claim 20, wherein a cut-out is provided at a distal end of the cylindrical body.

23. The hinge of claim 19 or 20, wherein the cut-out portion comprises one or more sectors removed from an outer wall of the proximal end of the cylindrical body.

24. A hinge as claimed in claim 14 or any claim dependent on claim 14, wherein a permanent magnet is located within the piston or sleeve.

25. The door hinge spindle comprises an axial spindle including an attachment for engaging the door such that the spindle and door are forced to rotate together in use;

wherein the shaft further comprises:

a primary centering surface parallel to the axis of the shaft, and two secondary centering surfaces orthogonal to the primary centering surface;

wherein the two second centering surfaces extend in diametrically opposed relationship about the axis of the shaft;

wherein the shaft includes one or more stop surfaces angularly displaced from the primary centering surface at right angles to the primary centering surface and parallel to the shaft axis.

26. A hinge as claimed in claim 14 or any claim dependent on claim 14, wherein the piston is provided with one or more cut-outs at the end of the cylindrical sleeve.

27. A hinge as claimed in claim 26 wherein the or each cut-out portion comprises a planar sector removed from the end of the sleeve.

28. A hinge as claimed in any preceding claim wherein the biasing member does not intersect the shaft axis when extended.