GB2117825A

GB2117825A - Spring-biased hinge

Info

Publication number: GB2117825A
Application number: GB08305248A
Authority: GB
Inventors: R Rawlinson
Original assignee: Nico Manufacturing Ltd
Current assignee: Nico Manufacturing Ltd
Priority date: 1982-03-17
Filing date: 1983-02-25
Publication date: 1983-10-19
Also published as: GB2117825B; GB8305248D0

Abstract

A spring-biased concealed type of hinge which is usually used in pieces of furniture comprises a housing (4) and a hinge arm (3) joined together by a pair of pivoted links (6 and 7). As the hinge is opened, the hinge arm (3) rotates with respect to and moves away from the housing (4). The hinge also comprises a cantilever spring (18) which is attached to the hinge arm (3) and the free end (20) of which bears against one of the links (7). The cantilever spring (18) urges the link (7) to rotate with respect to the hinge arm (3) and thus biases the hinge into both its open and closed positions. <IMAGE>

Description

SPECIFICATION Spring biased hinge This invention relates to spring biased hinges particularly hinges of the concealed type usually used in pieces of furniture. Many spring biased hinges only bias the hinge into one of its limit positions, usually the closed position. The spring biased hinge with which the present invention is particularly concerned biases the hinge into both of its limit positions. The spring bias acts as a latch since it biases the hinge into its closed position and holds the hinge and thus the door in its closed position. The spring bias also holds the hinge and hence a door in its open position and so prevents inadvertant closure of the door. Of course the bias of the spring can be overcome by manual opening and closing of the door.

According to this invention a spring biased concealed type hinge comprises a housing and a hinge arm joined together by a pair of pivoted links, the arrangement being such that, as the hinge is opened, the hinge arm rotates with respect to and moves away from the housing, the hinge also comprising a cantilever spring which is attached to the hinge arm and the free end of which bears against one of the links, the cantilever spring urging the link to rotate with respect to the hinge arm and thus biasing the hinge into both its open and closed positions.

Preferably the free end of the cantilever spring bears against the outermost link of the pair, the outer link being the link furthest from the corner formed between the two pieces joined together by the hinge. When the free end of the cantilever spring bears against the outer link it may engage the outer link on the same side of a line joining the two pivot axes of the outer link as the attachment between the cantilever spring and the hinge arm.

In this case the free end of the cantilever spring exerts a force in a direction away from the corner formed between the pieces joined together by the hinge. However, it is preferred that the free end of the cantilever spring engages the outer link on the other side of the line joining the pivot axes and exerts a force in a direction towards the corner. In both cases, the cantilever spring urges the outer link to rotate in the same sense with respect to the hinge arm around the pivotal connection of the link and the hinge arm.

Preferably the cantilever spring includes at least two leaves and, in this case it is preferred that it is formed from a folded elongate spring steel strip.

Such a folded spring is preferably connected to the hinge arm by a rivet passing along the fold.

The cantilever spring is preferably cranked. The folded end of the cantilever spring may be fixed to the hinge arm or, if it is pivotally connected to the hinge arm, the bend in the cranked spring preferably engages the hinge arm which acts as a fulcrum to strain the spring in a direction to urge the link to rotate.

Preferably the hinge links are U-shaped in cross-section. In this case, the free end of the cantilever spring bears against one end of the base of the U. There may be a projection formed on the base to provide a larger surface area for the free end of the cantilever spring to bear against.

Preferably the hinge arm is U-shaped in crosssection and includes a detachable mounting plate.

The mounting plate is then fixed onto the side wall on which the hinge is to be mounted by wood screws or by fir tree fittings and the hinge arm is then fastened onto the mounting plate by a fixing screw and an adjusting screw.

In this case, preferably the spring has a slot or a hole to accommodate the adjusting screw.

Preferably the mounting plate and hinge are as described in our co-pending patent application published as publication No 2 101 200.

A particular example of a hinge in accordance with this invention will now be described with reference to the accompanying drawings; in which: Figure 1 is a plan of a hinge in its open position; Figure 2 is a plan of the hinge in its closed position; Figure 3 is a perspective view of the outer link; and, Figures 4A and B are a plan and an elevation of the cantilever spring in its relaxed position.

A hinge for hinging a door 1 onto a wall 2 of a piece of furniture comprises a hinge arm 3 and a housing 4. The hinge arm 3 is generally U-shaped in cross-section. The housing 4 is a generally cylindrical cap-shaped housing which fits into a cylindrical hole in the door 1 and is fixed into position by wood screws (not shown) passing through a flange 5 formed at the open end of the housing 4. The housing 4 and the hinge arm 3 are linked together by two links, an inner link 6 and an outer link 7.

The outer link 7 is pivotally connected to the hinge arm 3 by a pivot pin 8 which is riveted to the hinge arm 3, and to the housing 4 by a pivot pin 9.

The inner link 6 is pivotally connected to the hinge arm and the housing by pins 10 and 11.

The links 6 and 7 are substantially U-shaped in cross-section. The outer link 7 is shown in more detail in Figure 3 and includes a base 12 and sides 13 and 14 with holes 15, 16 through which the pivot pins 8 and 9 are threaded. The base 12 of the link does not extend along the whole length of the sides 13 and 14 and terminates in an abutment face 1 7.

As the door 1 is moved from its open to its closed position the housing 4 rotates and moves towards the hinge arm 3. During this movement the outer link 7 rotates with respect to the hinge arm 3 first in a clockwise direction as seen in Figures 1 and 2, and then in an anticlockwise direction.

A centilever spring 18 is formed by a folded steel spring strip, pivotally connected to the hinge arm 3 by a rivet 19. The spring 18 is cranked and in its relaxed state has a configuration as shown in Figure 4A. The free end 20 of the cantilever spring 1 8 bears against the abutment face 1 7 of the base 12 of the U-shaped link 7. The spring is strained against the abutment face 1 7, a projection 21 on the hinge arm 3, and the rivet 1 9 so that its free end 20 urges the abutment face 1 7 away from the hinge arm 3 and so urges the link 7 to rotate in an anticlockwise direction about its pivot pin 8 with respect to the hinge arm 3.

During the movement of the hinge from its open position to its closed position for the first part of the movement of the outer link 7 rotates in a clockwise direction, and thus the spring 1 8 opposes the movement and thus the spring 1 8 tends to hold the hinge and the door 1 in its open position. Further closure of the door 1 causes the link 7 to start to move in an anticlockwise direction and the cantilever spring 1 8 promotes this rotation and thus urges the hinge into its closed position. Thus the spring 1 8 urges the door 1 to close.

The hinge also includes a mounting plate 22 which is fixed to the wall 2 by two wood screws 23 and to which the hinge arm 3 is connected by a fixing screw 24 and an adjustment screw 25. The spring 1 8 includes a slot 26 to accommodate the adjustment screw 25.

Claims

1. A spring biased concealed type hinge comprising a housing and a hinge arm joined together by a pair of pivoted links, the arrangement being such that, as the hinge is opened, the hinge arm rotates with respect to and moves away from the housing, the hinge also comprising a cantilever spring which is attached to the hinge arm and the free end of which bears against one of the links, the cantilever spring urging the link to rotate with respect to the hinge arm and thus biasing the hinge into both its open and closed positions.

2. A spring biased hinge according to claim 1, in which the free end of the cantilever spring bears against the outermost link of the pair, the outer link being the link furthest from the corner formed between the two pieces joined together by the hinge.

3. A spring biased hinge according to claim 2, in which the free end of the cantilever spring engages the outer link on the other side of a line joining the pivot axes and exerts a force in a direction towards the corner formed between the two pieces joined by the hinge.

4. A spring biased hinge according to any one of the preceding claims, in which the cantilever spring includes at least two leaves and is formed from a folded elongate spring steel strip.

5. A spring biased hinge according to claim 4, in which the folded spring is connected to the hinge arm by a rivet passing along the fold.

6. A spring biased hinge according to any one of the preceding claims, in which the cantilever spring is cranked, and the bend in the cranked spring engages the hinge arm which acts as a fulcrum to strain the spring in a direction to urge the link to rotate.

7. A spring biased hinge according to any one of the preceding claims, in which the hinge links are U-shaped in cross-section and the free end of the cantilever spring bears against the end of the base of the U.

8. A spring biased hinge according to any one of the preceding claims, in which the hinge arm is U-shaped in cross section and includes a detachable mounting plate, the mounting plate being arranged to be fixed onto the side wall on which the hinge is to be mounted and the hinge arm being fastened onto the mounting plate by a fixing screw and an adjusting screw.

9. A spring biased hinge substantially as described with reference to the accompanying drawings.