GB2102488A - Self-releasing hook - Google Patents

Abstract

There is described a self releasing hook of tubular or rectangular section consisting of two components 1, 5 which are slideable one within the other. The hook may be hung from a crane or hoist and is released by either gravity (as shown) or spring means causing the two sections of the hook to slide one within the other and raising portion 4 from load bearing portion 2. <IMAGE>

Description

SPECIFICATION Self releasing hook This invention relates to a self releasing hook of either tubular or rectangular section consisting of two components which are slidable one within the other.

The hook is hung from a crane or hoist and is used in conjunction with a sling which is permanenently attached to the hook at one end by means of a shackle or other means and which has a link at the other end which is held on a load bearing piece or section of the hook so that the load is suspended in the bite of the sling.

The link is released by either gravity causing the two sections of the hook to slide within one another when the lower section is supported on a surface or by a spring attached to the two sections causing the two sections to slide one within the other when the load on the hook becomes less than the tension on the spring so that the link end of the sling may be drawn out from the load by the end which is attached to the hook by the shackle or other means.

Where the hook is suspended by the outer section, the sling is permanently attached at one end to the inner section and the link is held in the load bearing section of the outer section by a locking piece attached to or being part of the inner section.

Where the hook is suspended by the inner section the sling is permanently attached at one end to the outer section and the link is held in the load bearing section of the inner section by a locking piece attached to or being part of the outer section.

Embodiments of the invention will now be described by way of example, with reference to the accompanying drawings in which: Figure 1 and Figure 1B show diagramatically a self-releasing hook of tubular section which is suspended from the crane or hoist by its outer section and is released by gravity causing the outer section to lower upon the inner section as shown in Figures 1A and 1C respectively.

Figure 2 shows the same hook as in Figure 1 except that release is caused by a spring biassing the inner tube to lift within the outer tube when the load is set down, as shown in Figure 2A.

Figure 3 shows diagramatically a self releasing hook of tubular section which is suspended from the crane or hoist by its inner section and is released by gravity causing the inner section to lower within the outer section as shown in Figure 3A Figure 4 shows the same hook as in Figure 3 except that release is is caused by a spring biassing the outer tube to lift upon the inner tube when the load is set down as shown in Figure 4A Figure 5shows diagramatically a self-releasing hook of rectangular section which is suspended from a crane or hoist by its inner section and is released by gravity causing the inner section to lower within the outer section when the load is set down as shown in Figure 5A.

Figure 6 shows the same hook as in Figure 5 except that release is caused by a spring biassing the outer section to lift upon the inner section when the load is set down.

In Figures 1, lA, iB, iC, 2, 2A,3,3A,4,4A, 5, 5A,6 and 6A the hook is suspended from the crane or hoist by section 1 having a load bearing point 2. The standing part of the sling is attached to point 3 and the link on the other end of the sling is held into the load bearing section 2 by the locking piece 4 which is part of the same member 5 as shackle point 3. In Figures 2, 2A, 4, 4A, 6 and 6A, releasing spring 6 is attached to section 1 at point 7 and to section 5 at point 8, the spring biassing section 5 to lift upon section 1 when the load is set down.

1. A self releasing hook comprised oftwo main parts of either tubular or rectangular section which move telescopically one within the other, which is suspended from a crane or hoist by either the outer section or the inner section respectively and when so suspended by the outer section a point is provided on the inner section for the permanent attachment of one end of a sling which has a link on the other end which when bearing a load is held into a load bearing section of the outer section by a locking piece attached to the inner section and which releases the said link when the effect of gravity causes the inner section to move telescopically within the outer section when the hook is set down upon the load or other surface; or when the hook is suspended by the inner section, a point is provided on the outer section for the permanent attachment of one end of a sling which has a link on its other end which when bearing a load is held into a load bearing point on the inner section by a locking piece attached to the outer section and which releases the said link when the effect of gravity causes the outer section to move telescopically within the inner section when the hook is set down upon the load or other surface respectively, thereby releasing the link at one of the sling so that it may be drawn out from the load or from the lifting equipment attached to the load.

2. A self releasing hook according to claim 1, including a spring attached to the two sections of the hook biassing them to move telescopically one within the other when the load is set down so that the weight on the hook becomes less than the tension in the spring and thereby releasing the link on one end of the sling so that the sling may be drawn out from the load or from the lifting equipment attached to the load.

3. A self releasing hook substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Self releasing hook This invention relates to a self releasing hook of either tubular or rectangular section consisting of two components which are slidable one within the other. The hook is hung from a crane or hoist and is used in conjunction with a sling which is permanenently attached to the hook at one end by means of a shackle or other means and which has a link at the other end which is held on a load bearing piece or section of the hook so that the load is suspended in the bite of the sling. The link is released by either gravity causing the two sections of the hook to slide within one another when the lower section is supported on a surface or by a spring attached to the two sections causing the two sections to slide one within the other when the load on the hook becomes less than the tension on the spring so that the link end of the sling may be drawn out from the load by the end which is attached to the hook by the shackle or other means. Where the hook is suspended by the outer section, the sling is permanently attached at one end to the inner section and the link is held in the load bearing section of the outer section by a locking piece attached to or being part of the inner section. Where the hook is suspended by the inner section the sling is permanently attached at one end to the outer section and the link is held in the load bearing section of the inner section by a locking piece attached to or being part of the outer section. Embodiments of the invention will now be described by way of example, with reference to the accompanying drawings in which: Figure 1 and Figure 1B show diagramatically a self-releasing hook of tubular section which is suspended from the crane or hoist by its outer section and is released by gravity causing the outer section to lower upon the inner section as shown in Figures 1A and 1C respectively. Figure 2 shows the same hook as in Figure 1 except that release is caused by a spring biassing the inner tube to lift within the outer tube when the load is set down, as shown in Figure 2A. Figure 3 shows diagramatically a self releasing hook of tubular section which is suspended from the crane or hoist by its inner section and is released by gravity causing the inner section to lower within the outer section as shown in Figure 3A Figure 4 shows the same hook as in Figure 3 except that release is is caused by a spring biassing the outer tube to lift upon the inner tube when the load is set down as shown in Figure 4A Figure 5shows diagramatically a self-releasing hook of rectangular section which is suspended from a crane or hoist by its inner section and is released by gravity causing the inner section to lower within the outer section when the load is set down as shown in Figure 5A. Figure 6 shows the same hook as in Figure 5 except that release is caused by a spring biassing the outer section to lift upon the inner section when the load is set down. In Figures 1, lA, iB, iC, 2, 2A,3,3A,4,4A, 5, 5A,6 and 6A the hook is suspended from the crane or hoist by section 1 having a load bearing point 2. The standing part of the sling is attached to point 3 and the link on the other end of the sling is held into the load bearing section 2 by the locking piece 4 which is part of the same member 5 as shackle point 3. In Figures 2, 2A, 4, 4A, 6 and 6A, releasing spring 6 is attached to section 1 at point 7 and to section 5 at point 8, the spring biassing section 5 to lift upon section 1 when the load is set down. CLAIMS

1. A self releasing hook comprised oftwo main parts of either tubular or rectangular section which move telescopically one within the other, which is suspended from a crane or hoist by either the outer section or the inner section respectively and when so suspended by the outer section a point is provided on the inner section for the permanent attachment of one end of a sling which has a link on the other end which when bearing a load is held into a load bearing section of the outer section by a locking piece attached to the inner section and which releases the said link when the effect of gravity causes the inner section to move telescopically within the outer section when the hook is set down upon the load or other surface; or when the hook is suspended by the inner section, a point is provided on the outer section for the permanent attachment of one end of a sling which has a link on its other end which when bearing a load is held into a load bearing point on the inner section by a locking piece attached to the outer section and which releases the said link when the effect of gravity causes the outer section to move telescopically within the inner section when the hook is set down upon the load or other surface respectively, thereby releasing the link at one of the sling so that it may be drawn out from the load or from the lifting equipment attached to the load.

2. A self releasing hook according to claim 1, including a spring attached to the two sections of the hook biassing them to move telescopically one within the other when the load is set down so that the weight on the hook becomes less than the tension in the spring and thereby releasing the link on one end of the sling so that the sling may be drawn out from the load or from the lifting equipment attached to the load.

3. A self releasing hook substantially as hereinbefore described with reference to the accompanying drawings.