GB2157757A

GB2157757A - Pulling device

Info

Publication number: GB2157757A
Application number: GB08503042A
Authority: GB
Inventors: Paul Rafter
Original assignee: Institue for Industrial Research and Standards
Current assignee: Institue for Industrial Research and Standards
Priority date: 1984-02-06
Filing date: 1985-02-06
Publication date: 1985-10-30
Also published as: DE3503201A1; AU3849485A; GB8503042D0; IE840268L

Abstract

A device for pulling a calf's leg, when assisting at the birth, comprises a continuous length of rope 1 having a double half hitch knot 2 forming a double loop 3 for fitting on the calf's leg, a sleeve 4 for retaining the rope in the double half hitch configuration and for distributing the pressure of the double loop 3 on the calf's leg, and a single loop 5 which may be gripped to pull the calf's leg. The double loop 3 is reduced around the leg by pulling at 1a or 1b, and the leg is then pulled by pulling at 1c. <IMAGE>

Description

SPECIFICATION Pulling device The present invention relates to pulling devices. Situations arise in which a rope is tied to an animal and is then used to pull the animal. For example, when assisting at the birth of a calf, the calf may be pulled from the cow by means of a rope attached to the calf's legs.

Unfortunately, many people handling animals persist in securing ropes to animals' legs by means of knots which are self tightening so that as a pull is exerted on the rope, the rope closes more and more tightly around the animal's leg, damaging underlying soft tissue and fracturing bones.

The present invention provides a pulling device comprising a length of rope or cord formed into a configuration which includes a loop which, by appropriate pulling on the length of rope, may be reduced to close around the object to be pulled and then fixed to prevent the object being damaged during pulling, apd retaining means disposed on the length of rope for holding the length in the above configuration.

Advantageously, the configuration is that of a double half hitch. Pulling on either end of the length reduces the double loop, but pulling both ends simultaneously fixes the double loop.

Advantageously, the two ends of the length are joined together, forming a further loop.

Pulling may be carried out by pulling on the further loop which serves as a convenient handle and which ensures equal tension on both ends, instead of having to pull two separate ends with equal tension simultaneously.

Advantageously, the retaining means comprises a sleeve through which passes the double loop of the double half hitch.

The invention will now be described more particularly with reference to the accompanying drawing which illustrates, by way of example, a device according to the invention for use in assisting at the birth of a calf. The drawing shows a length of rope 1 provided with a double half hitch knot 2 forming a double loop 3. A sleeve 4 holds the knot 2 and double loop 3 in position. The ends of the length of rope are joined, thereby making the rope 1 continuous and forming a further single loop 5. The ends are joined by splicing, thereby preventing the knot 2 from becoming undone by either end escaping through the sleeve 4. Joining the ends also provides a convenient handle as is explained below.

In use, two devices are employed, one for each leg. The double loop 3 is slid over the calf's hoof and up the calf's leg to the narrow part above the ankle. The double loop 3 is then reduced by pulling the rope 1 at either 1 a or 1 b. When the double loop 3 is suitably reduced, the leg may then be pulled by holding the rope in the handle region Ic and pulling. Pulling at Ic ensures that there is equal tension in 1 a and 1 b and that the knot 2 locks so that the size of the double loop 3 remains constant.

The rope 1 is about one metre long. The size of the double loop 3 varies between 25cm when being fitted over the hoof and 1 6cm when fixed for pulling. The sleeve 4 is 1 6cm long so that it extends all the way around the double loop 3 when the double loop is fixed for pulling, and distributes the pressure of the double loop 3 on the animal's leg. The rope 1 is made from three triple strands of polypropylene fibrillated film, is 7mm in diameter and has a tensile strength capable of bearing a weight of 500 kg. The sleeve 4 is made from polypropylene sheet.

The device weighs 50 g.

The device is capable of being cleaned and re-used without risk of infection.

In a modification of the device, the ends are joined by two metal clips instead of by splicing.

1. A pulling device comprising a length of rope or cord formed into a configuration which includes a loop which, by appropriate pulling on the length of rope, may be reduced to close around the object to be pulled and then fixed to prevent the object being damaged during pulling, and retaining means disposed on the length of rope for holding the length in the above configuration.

2. A device according to Claim 1, in which the configuration is that of a double half hitch, whereby pulling on either end of the length reduces the double loop but pulling both ends simultaneously fixes the double loop.

3. A device according to Claim 2, in which the two ends of the length are joined together forming a further single loop, whereby pulling may be carried out by pulling on the further loop which serves as a convenient handle and equalizes tension between the two ends.

4. A device according to Claim 3 in which the joining of the two ends is by means of splicing 5. A device according to Claim 3, in which the joining of the two ends is by means of one or more metal clips.

6. A device according to any of Claims 2, 3 4 or 5 in which the retaining means comprises a sleeve through which passes the double loop of the double half hitch.

7. A device according to Claim 6, in which the length of the sleeve is approximately the circumference of the narrowest part of a calf's leg, whereby when the device is used to pull a calf's leg the sleeve distri

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Pulling device The present invention relates to pulling devices. Situations arise in which a rope is tied to an animal and is then used to pull the animal. For example, when assisting at the birth of a calf, the calf may be pulled from the cow by means of a rope attached to the calf's legs. Unfortunately, many people handling animals persist in securing ropes to animals' legs by means of knots which are self tightening so that as a pull is exerted on the rope, the rope closes more and more tightly around the animal's leg, damaging underlying soft tissue and fracturing bones. The present invention provides a pulling device comprising a length of rope or cord formed into a configuration which includes a loop which, by appropriate pulling on the length of rope, may be reduced to close around the object to be pulled and then fixed to prevent the object being damaged during pulling, apd retaining means disposed on the length of rope for holding the length in the above configuration. Advantageously, the configuration is that of a double half hitch. Pulling on either end of the length reduces the double loop, but pulling both ends simultaneously fixes the double loop. Advantageously, the two ends of the length are joined together, forming a further loop. Pulling may be carried out by pulling on the further loop which serves as a convenient handle and which ensures equal tension on both ends, instead of having to pull two separate ends with equal tension simultaneously. Advantageously, the retaining means comprises a sleeve through which passes the double loop of the double half hitch. The invention will now be described more particularly with reference to the accompanying drawing which illustrates, by way of example, a device according to the invention for use in assisting at the birth of a calf. The drawing shows a length of rope 1 provided with a double half hitch knot 2 forming a double loop 3. A sleeve 4 holds the knot 2 and double loop 3 in position. The ends of the length of rope are joined, thereby making the rope 1 continuous and forming a further single loop 5. The ends are joined by splicing, thereby preventing the knot 2 from becoming undone by either end escaping through the sleeve 4. Joining the ends also provides a convenient handle as is explained below. In use, two devices are employed, one for each leg. The double loop 3 is slid over the calf's hoof and up the calf's leg to the narrow part above the ankle. The double loop 3 is then reduced by pulling the rope 1 at either 1 a or 1 b. When the double loop 3 is suitably reduced, the leg may then be pulled by holding the rope in the handle region Ic and pulling. Pulling at Ic ensures that there is equal tension in 1 a and 1 b and that the knot 2 locks so that the size of the double loop 3 remains constant. The rope 1 is about one metre long. The size of the double loop 3 varies between 25cm when being fitted over the hoof and 1 6cm when fixed for pulling. The sleeve 4 is 1 6cm long so that it extends all the way around the double loop 3 when the double loop is fixed for pulling, and distributes the pressure of the double loop 3 on the animal's leg. The rope 1 is made from three triple strands of polypropylene fibrillated film, is 7mm in diameter and has a tensile strength capable of bearing a weight of 500 kg. The sleeve 4 is made from polypropylene sheet. The device weighs 50 g. The device is capable of being cleaned and re-used without risk of infection. In a modification of the device, the ends are joined by two metal clips instead of by splicing. CLAIMS

4. A device according to Claim 3 in which the joining of the two ends is by means of splicing

5. A device according to Claim 3, in which the joining of the two ends is by means of one or more metal clips.

7. A device according to Claim 6, in which the length of the sleeve is approximately the circumference of the narrowest part of a calf's leg, whereby when the device is used to pull a calf's leg the sleeve distri butes the pressure on the calf's leg.

8. A device according to any one of the preceding claims, in which the length of rope and the retaining means are made from materials which can be cleaned and re-used, without risk of spreading infection.

9. A device according to any one of the preceding claims, in which the rope is of polypropylene.

10. A device according to Claim 6 or Claim 7, in which the sleeve is of polypropylene sheet.

11. A pulling or hoisting device substantially as herein described with reference to and as shown in the accompanying drawing.