GB1601772A - Device for splitting nuts - Google Patents

Description

(54) DEVICE FOR SPLITTING NUTS (71) We, GKN BOLTS & NUTS LIMI TED, a British Company of Kings Hill, Wednesbury, West Midlands. WSl0 7SJ, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to devices used for disengaging a nut from a bolt by splitting the nut.

Such a device used for splitting a nut in order to disengage it from a bolt will hereinafter be referred to as a "nut cracker".

When a nut is seized up on a bolt of considerable size, and conventional means such as spanners will not release it, then the nut can be forcibly split to give a small vertical gap in order to release it from the bolt.

One known method involves sawing the side of the nut and then using a cold chisel to force the cut open.

According to one aspect of the invention we provide a nut cracker having a frame in the form of a load bearing closed loop, all of the loop being capable of bearing load, with an abutment for location of a nut, a piston and cylinder assembly supported on the frame, and a sharp edged tool arranged to be driven by the piston and cylinder assembly towards a nut located by the abutment, to split the nut.

Preferably the piston and cylinder assembly comprises a piston and cylinder, one being propelled relative to the other by the pressure of fluid forced in an elastomer bag, capable of expansion, which is located between the piston crown and the cylinder head.

Normally the cylinder is fixed to the frame and the piston is movable relative to the cylinder, the piston carrying the tool.

The invention will now be described, by way of example only, with reference to the accompanying drawings in which: FIGURE 1 shows a plan view of a nut cracker in accordance with the present invention; FIGURE 2 shows a section along the line A-A of Figure 1.

Referring now to Figures 1 and 2 these show a frame 10, in the form of a load bearing closed loop all of the loop being capable of bearing load, surrounding a piston and cylinder assembly body 12. The body contains a movable piston 14 and a fixed cylinder 16. A tool holder 18 is attached to the piston by screws 20. A sharp edged tool 22 of hard material is secured to the tool holder 18 and centred by set screws 24. The bottom of the tool 22 is radiused at 26 to allow it to ride over, for example, a washer, without fouling.

Between the cylinder head 28 and the piston crown 30 is an elastomer bag 32, capable of expansion. Fluid under pressure can be introduced into the bag 32 via a port 34, piping 36 and an entry seal 38. Fluid pressure in the bag 32 forces the elastomer walls 40 of the bag 32 into a cylindrical slot 42 in the cylinder 16, giving a seal which becomes more effective as the pressure inside the bag 32 increases.

Similarly the seal between the bag 32 and the piston 14 becomes more effective at higher pressure as the piston walls 44, which are tapered and of smaller cross-section in this area, are forced against the cylinder walls 46.

At the opposite end of the frame 10 to the cylinder 16 there is an abutment 48 for receiving a nut to be split. A guard 50 partially covers the region in which the nut can be received.

In use the nut cracker is arranged over a nut to be split, with any bolt shank which projects beyond the nut extending through the opening in the guard 50.

Fluid under pressure is forced into the bag 32 which expands and pushes the piston 14 towards the nut. The tool 22 is thus forced towards the nut, and the sharp edge 52 of the tool, which edge lies parallel to the axis of the nut, penetrates the side of the nut, thus splitting it. This loosens the nut on the bolt so that it can be unscrewed.

Claims (4)

WHAT WE CLAIM IS:

1. A nut cracker having a frame in the form of a loadbearing closed loop, all of the loop being capable of bearing load, with an abutment for location of a nut, a piston and cylinder assembly supported on the frame, and a sharp edged tool arranged to be driven by the piston and cylinder assembly towards a nut located by the abutment, to split the nut.

2. A nut cracker according to claim 1 in which the piston and cylinder assembly comprises a piston and a cylinder, one being propelled relative to the other by the pressure of fluid forced into an elastomer bag, capable of expansion, which is located between the piston crown and the cylinder head.

3. A nut cracker according to claim 1 or claim 2 in which the cylinder is fixed to the frame, and the piston is movable and carries the tool.

4. A nut cracker arranged substantially as hereinbefore described with reference to the accompanying drawings.