Door or gate closing hinge

The adjustable self-closing hinge (1) comprises a first hinge part (2), a second hinge part (3), a hinge shaft (10), a torsion spring (18) having a first end (19) fixed with respect to the first hinge part (2) and a second end (20) fixed with respect to the hinge shaft (10) to exert a moment onto the first hinge part, and means for adjusting the moment exerted by the torsion spring on the first hinge part. These adjusting means comprise a coupling element (21) which is interposed between the first end (19) of the torsion spring (18) and the first hinge part (2) and which is rotatably mounted in the first hinge part, and a screw-like element (24) which is rotatably mounted in the first hinge part (2) and which is arranged to cooperate with the coupling element (21) to rotate the coupling element with respect to the first hinge part so as to adjust the moment exerted by the torsion spring on the first hinge part.

BACKGROUND OF THE INVENTION

The present invention relates to a gate or door closing hinge comprising a first hinge part, a second hinge part, a hinge shaft rotatably mounted about a first rotation axis in the first hinge part and connecting the first hinge part to the second hinge part, a torsion spring having a longitudinal axis coinciding substantially with said first rotation axis and having a first end fixed with respect to the first hinge part and a second end fixed with respect to the hinge shaft to exert a door or gate closing moment onto the first hinge part, and means for adjusting the moment exerted by the torsion spring on the first hinge part.

Hinges comprising a torsion spring for closing the door or gate against which they are mounted are known. When assembling the hinges, the torsion spring is pre-tensioned so that the door or gate has to be opened against a predetermined spring tension. In practice, there exist moreover systems for adjusting the tension of the torsion spring when the hinges are already mounted on the door or gate. An example of such a system are the TRU-CLOSE® adjustable self-closing gate hinges which are available on the market.

The TRU-CLOSE® adjustable self-closing gate hinges are mounted in the same way as conventional hinges on the outside of the gate and the pole. The torsion spring is arranged within the hinge, around the hinge shaft. The hinge shaft has a hexagonal head which fits in a cavity in the second hinge part. By means of a screwdriver, the hexagonal head can be depressed against the action of the helical torsion spring and rotated to adjust the tension of the torsion spring. In this way a quite compact adjusting system is achieved. A drawback of such an adjustment system is however that, when depressing the head of the hinge shaft, the screwdriver has to be held very strongly and a large force has to be exerted thereon in order to be able to increase the tension of the torsion spring. Indeed, when depressing the hexagonal head, the entire tension of the torsion spring acts upon the screwdriver.

SUMMARY OF THE INVENTION

An object of the present invention is now to provide a new type of self-closing hinges which comprise a torsion spring, the tension of which can be adjusted more easily, i.e. without having to hold the entire tension of the torsion spring when adjusting the tension, and which can be kept relatively compact.

To this end, the hinge according to the invention is characterised in that the means for adjusting the moment exerted by the torsion spring on the first hinge part comprise a coupling element, which is interposed between the first end of the torsion spring and the first hinge part and which is rotatably mounted in the first hinge part about a second rotation axis which coincides substantially with the first rotation axis, and a screw-like element which is rotatably mounted in the first hinge part about a third rotation axis and which has a screw threaded portion arranged to co-operate with the coupling element to rotate the coupling element with respect to the first hinge part upon rotation of the screw-like element about the third rotation axis so as to adjust the moment exerted by the torsion spring on the first hinge part.

In the lock according to the invention, the moment exerted by the torsion spring on the first hinge part, in other words the spring tension, can be easily adjusted by rotating the screw-like element by means of a screwdriver or a spanner. The screw threaded portion on the screw-like element provides for a connection between the coupling element and the first hinge part which maintains the coupling element in position with respect to the first hinge part and which enables moreover to adjust this position without having to disconnect the coupling element from the first hinge part. The tension of the torsion spring is therefore always taken up by the first hinge part, even when adjusting this tension by rotating the screw-like element. Moreover, since the tension of the torsion spring is adjusted indirectly by rotating the coupling element by means of the screw threaded portion on the screw-like element, a smaller force has to be exerted by means of the screwdriver or the spanner onto the screw-like element than the force which has to be exerted onto the torsion spring itself to increase the tension thereof. The angular displacement of the torsion spring will indeed be smaller than the corresponding angular displacement of the screw-like element. A further advantage of the hinge according to the invention is that the adjustment system with coupling element and screw-like element can be kept relatively compact.

In a first particular embodiment of the hinge according to the invention, the coupling element has a helical guide, in particular a helical groove, extending around the second rotation axis and the screw-like element co-operates with the coupling element through the intermediary of a guided element arranged to move along said helical guide upon rotation of the screw-like element to rotate the helical guide and hence the coupling element with respect to the first hinge part.

An advantage of this embodiment is that the screw-like element can be arranged in a direction parallel to the rotation axis of the hinge shaft so that the tension of the torsion spring can be adjusted from the upper side of the hinge. Such an embodiment enables for example to mount the first hinge part within a vertical tube element of the door or gate whilst still enabling an adjustment of the spring tension in the mounted state of the hinge without having to drill a lateral hole in the tube element.

In a second particular embodiment of the hinge according to the invention, the coupling element comprises a worm wheel and the screw threaded portion of the screw-like element forms a worm cooperating with the worm wheel of the coupling element to rotate the coupling element with respect to the first hinge part upon rotation of the screw-like element.

An advantage of this embodiment is that the coupling element can be rotated as much as desired by means of the screw-like element, i.e. the number of rotations of the coupling element and thus of the torsion spring are not limited by the adjustment system.

In a preferred embodiment of the hinge according to the invention, the first hinge part comprises a tubular housing enclosing at least the hinge shaft, the torsion spring and the coupling element, the tubular housing of the first hinge part being in particular arranged to be mounted in a tubular element fixed against the door or gate or in a tubular frame member of the gate or door itself.

Due to the fact that in the hinge according to the invention the adjustment mechanism can be kept relatively compact, this preferred embodiment offers the advantage that the first hinge part and all the components of the hinge enclosed thereby can be mounted in a tubular element mounted against the door or gate or even in a tubular vertical frame member of the door or gate itself. The advantage of mounting the first hinge part in a tubular vertical element is that the self-closing system is vandal proof and hidden from view. The interior of the vertical frame member offers further a long cavity so that the length of the first hinge part, and especially the length of the torsion spring, can be increased without achieving an aesthetically not acceptable hinge. By being free to choose the length of the torsion spring, this length (i.e. the number of windings) can be selected in view of the desired spring properties. Moreover, it is possible to increase also the length of the hinge shaft and to add one or more additional torsion springs underneath the first torsion spring between the hinge shaft and the first hinge part to increase the spring tension for example when the hinge is applied to a larger and heavier door or gate.

DETAILED DESCRIPTION

The adjustable self-closing hinge1illustrated inFIG. 1comprises a first hinge part2arranged to be mounted to a door or gate and a second hinge part34arranged to be mounted to a vertical support, in particular to a pole5.

The second hinge part3is generally L-shaped. One leg of the L-shape is formed by a bolt portion6applied through two opposite holes in the pole and fixed to the pole5by means of two nuts7, one on each side of the pole5. The other leg of the L-shaped hinge part3is a cylindrical shaft8which fits in a cylindrical hole9provided, as explained hereinafter, in the upper side of the actual hinge shaft10received in the first hinge part2.

The first hinge part2has a tubular shape so that it can be mounted in a vertical tubular member11of the door or gate4. In the mounted state, the first hinge part2is thus hidden from view. A further advantage of mounting the first hinge part in the tubular gate member is that the hinge is more vandal proof. The length of the tubular gate member11enables moreover to increase the length of the first hinge part2and of all the components of the hinge enclosed thereby. A problem with mounting the first hinge part2and the hinge components rendering the hinge self-closing and adjustable is however that the tubular gate member has a relatively small diameter (for example a diameter of 40 mm) so that the hinge has to be of a relatively compact construction.

As illustrated more into detail inFIGS. 3 and 4, the first hinge part2comprises a tubular housing12, a top part13arranged to be fixed to the top of the tubular housing12and a bottom part14arranged to be fixed to the bottom of the tubular housing12. The actual hinge shaft10is rotatably mounted about a first rotation axis15in the first hinge part2. The hinge shaft10has more particularly a thickened cylindrical head portion16which fits in a cylindrical cavity formed by a downward collar17on the top part13of the first hinge part2.

To render the hinge self-closing, a helical torsion spring18is applied over the hinge shaft10so that its longitudinal axis coincides with the first rotation axis15. The torsion spring18has a first end19fixed with respect to the first hinge part2and a second end20fixed with respect to the hinge shaft10(the second end20of the spring18is arranged in a hole (not shown) in the bottom of the head portion16of the hinge shaft10) to exert a moment onto the first hinge part2. In this way, the first hinge part2rotates against the action of the torsion spring18with respect to the hinge shaft10when opening the door or gate4and the door or gate4is closed back under the action of the torsion spring18.

In order to enable to adjust the tension of the torsion spring18, the first end19of the torsion spring is not fixed directly to the first hinge part2but is fixed thereto through the intermediary of a coupling element21. This coupling element21has a generally cylindrical tubular shape and is applied in the housing portion12of the first hinge part2over the torsion spring18. The coupling element21fits in the tubular housing12of the first hinge part2and is rotatably fixed to the bottom part14thereof by means of a screw22. The coupling element21can rotate in the housing12about a second rotation axis23which coincides with the first rotation axis15of the hinge shaft10. The first end19of the torsion spring18is applied in a hole (not shown) in the bottom of the coupling element21so that the (pre)tension of the torsion spring18can be adjusted by rotating the coupling element21with respect to the hinge shaft10without rotating the first hinge part2with respect to the hinge shaft.

In order to enable to achieve this rotation of the coupling element21with respect to the hinge shaft10and with respect to the first hinge part2, the adjusting means further comprise a screw-like element24which is rotatably mounted in the first hinge part2about a third rotation axis25parallel to the first rotation axis15. The screw-like element24extends through holes in the top13and bottom parts14of the first hinge part2and is fixed underneath the bottom part14by means of a nut27so that it can only rotate in the first hinge part but not move up or down. The screw-like element24has a screw threaded portion26which is screwed in an internally screw-threaded hole28in an element29guided in a helical guide, more particularly in a helical groove30, on the outer surface of the coupling element21. The element29is further guided in a linear guide, more particularly a linear groove31, on the inner side of the tubular housing12of the first hinge part2. This linear groove31extends parallel to the rotation axis25of the screw-like element24whilst the helical groove30in the coupling element21extends around the rotation axis23of the coupling element21. By rotating the screw-like element24in the guided element29, this guided element29can be moved up and down in the linear groove31in the first hinge part2and at the same time in the helical groove30in the coupling element21thereby rotating the coupling element21with respect to the first hinge part2and thus adjusting the tension of the torsion spring18.

Due to the fact that the guided element29cannot move up or down by the presence of the screw-like element24the coupling element21is constantly blocked in a particular angular position with respect to the hinge shaft10, even when adjusting the tension of the torsion spring18by rotating the screw-like element24. This screw-like element24is prevented from bending by the fact that the guided element is guided in the linear groove31in the first hinge part2. In this way, a relatively thin screw-like element and a relatively small guided element can be used whilst still assuring a reliable connection between the coupling element21and the first hinge part2.

In the embodiment illustrated inFIG. 4the coupling element24can be rotated over about one turn. For such a one-turn rotation of the coupling element21, the screw-like element24has to be rotated over somewhat more than thirty turns. Preferably, one rotation of the screw-like element24over 360° causes the coupling element21to rotate over an angle of less than 36°, and more preferably over an angle of less than 18° (i.e. one turn of the coupling element requires preferably at least 10 turns, and more preferably at least 20 turns of the screw-like element).

By the use of a screw-like element24cooperating with the coupling element21to rotate it, only relatively little power is required to tension the torsion spring by rotating the screw-like element24. Moreover, the screw-like element24the coupling element21is constantly blocked in a particular angular position with respect to the hinge shaft10, even when adjusting the tension of the torsion spring18by rotating the screw-like element24.

In order to render the door or gate4self-closing, the second hinge part3could be mounted or fixed (for example welded) irrotatably to the hinge shaft10so that opening the door or gate causes the hinge shaft10to rotate against the tension of the torsion spring18with respect to the first hinge part2. A drawback of such a self-closing hinge is that when using it for a door or gate which can swing over a large angle, for example a (double) door or gate which can be opened in two directions namely in the normal opening direction against the action of the torsion spring and in the opposite direction, it was found that the torsion spring may get stuck in the coupling element due to the increasing diameter of the torsion spring when opening the door in the opposite direction. When the torsion spring gets stuck in the coupling element, there is a risk that the second end20of the torsion spring18may break of when further opening the door or gate, especially when the door or gate can be rotated over an angle of about 180° in both directions as in the illustrated embodiment.

To enable to rotate the door or gate also in the direction opposite the normal opening direction over an angle of about 180° without any risk of damaging the torsion spring, the second hinge part3is rotatably mounted in the illustrated embodiment on the hinge shaft10, more particularly by inserting the cylindrical shaft8of the second hinge part3in the cylindrical hole9in the upper side of the hinge shaft10.

In order to avoid that the torsion spring18may get stuck in the coupling element21rotation of the first hinge part2with respect to the hinge shaft10under the moment exerted by the torsion spring18on the first hinge part2is limited to a predetermined mutual angular position by mutually co-operating stop means on the first hinge part2and on the hinge shaft10. The stop means on the first hinge part2comprise an abutment32on the upper surface of the top part13of the first hinge part2. The stop means on the hinge shaft10comprise a plate-like element33which is fixed by means of screws34to the head16of the hinge shaft10and which rests upon the upper surface of the top part13of the first hinge part2so that the hinge shaft2is rotatably fixed to the first hinge part2. The plate-like element33is substantially circular so that it can rotate along the abutment32on the first hinge part2but has a lateral projecting part35by means of which it abuts the abutment on the first hinge part to limit the rotation of the hinge shaft under the action of the torsion spring to a predetermined mutual angular position. In this position, the moment exerted by the torsion spring18on the first hinge part2is of a minimum value and increases when rotating the first hinge part2in a first rotational direction37, i.e. in the opening direction of the door or gate, with respect to the hinge shaft10.

Since the second hinge part3is rotatably connected to the hinge shaft10a further coupling between the second hinge part3and the hinge shaft10has to be provided so that the hinge shaft10is blocked with respect to the second hinge part3when opening the door or gate and the door or gate is thus opened against the moment exerted by the torsion spring on the first hinge part. This coupling comprises a stop formed by an upstanding lip36on the plate-like element33screwed onto the hinge shaft10. This lip36engages the second hinge part3to limit, on the one hand, rotation of the hinge shaft10in the opening direction37with respect to the second hinge part3to a predetermined mutual angular position but to enable, on the other hand, rotation of the hinge shaft10with respect to the second hinge part3in a second rotational direction opposite the opening direction37. Consequently, the door or gate can be opened in the normal opening direction against the moment exerted by the torsion spring18on the first hinge part2and can also be opened in the other direction without causing any further “uncoiling” of the torsion spring.

FIGS. 5 and 6show another embodiment of an adjustable self-closing hinge according to the invention. This hinge comprises a first hinge part2formed by a tubular housing12, a second hinge part3, a coupling element21which fits rotatably in the first hinge part housing12, a hinge shaft10having a head portion16fitting rotatably in the coupling element21and a torsion spring18arranged within the coupling element21around the hinge shaft10and having a first end19fixed to the coupling element21and a second end20fixed to the hinge shaft10. In the same way as in the previous embodiment, the second hinge part3is rotatably mounted in the hinge shaft10and the hinge shaft is provided on top with a plate-like element33limiting the rotation of the hinge shaft10with respect to the first hinge part2and having an upstanding lip36engaging the second hinge part3when opening the door or gate4against the spring action of the torsion spring18and enabling to open the door or gate4in the opposite direction without further “uncoiling” the torsion spring18.

As can be seen inFIG. 6, the construction of the coupling element21and of the screw-like element24is different from the construction of these elements in the previous embodiment. In the embodiment ofFIGS. 5 and 6the screw-like element is a worm24which can freely rotate in a hole40in an upper portion38of the first hinge part housing12and which co-operates with a worm wheel39provided on the upper side of the coupling element21. Rotation of the worm24around its rotation axis25, which is perpendicular to the hinge axis15, causes the coupling element21to rotate around the rotation axis23. The worm24also serves to fix the coupling element21in the first hinge part. The entry of the hole40is large enough to enable to insert the worm24in this hole after having inserted the coupling element21in the first hinge part housing12. The entry of the hole40is moreover provided with an internal screw thread so that a small screw41can be screw therein until it abuts the worm24to prevent any movement of the worm24.

From the above description it will be clear that the described embodiment can be amended in different ways without departing from the scope of the present invention as defined in the claims. For example instead of mounting the first hinge part into a vertical tubular member of the gate or door itself, it could also be mounted in a tubular element fixed for example by means of screws of by welding to a lateral side of the door or gate. Moreover, the first hinge part could be mounted in the same way against the support, in particular against the pole, to which the gate or door is to be suspended.

The hinge according to the invention enables to adjust the moment against which the door or gate can be opened. This moment can be adjusted in function of the personal preferences of the user. It also enables to overcome the typical spring fatigue problems associated with fixed-tension hinges. Adjusting the spring tension will also result in a different closing time. The hinge according to the invention can further be supplemented with a hydraulic or pneumatic device for adjusting the closing speed of the door or gate. Such a device can also be mounted in the tubular door or gate member.