AU647641B2 - A hydraulic grab - Google Patents

Description

AUSn T 7 6 4 1 Regulation 3.2 Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: A HYDRAULIC GRAB The following statement is a full description of this invention, including the best method of performing it known to me:- I I. I I I o° I HYDRAULIUC GRABBING DEVICE The machine is a hydraulically operated grabbing device, fitted to a tractor by either the three point linkage or a front end loader frame, with applications in agriculture and industry.

Dragging of logs, stumps and rocks causes deep gouges in pasture and can create erosion of top soils.

Most towing is currently done using chains from a tractor's draw bar to the object. The disadvantage of this is that the operator has to get off the tractor, run out the chain and find a way of passing the chain under the object and securing it before it can be dragged or towed. At the destination the operator again has to get off the tractor remove the chain and fold it away before the tractor can move off; and, because the object is being towed by chain the tractor can only move forward making it difficult to drop off the object accurately.

These problems are overcome by the hydraulic grab invention which allows objects to be grabbed firmly and carried with minimal disturbance to the soil and then placed accurately, without the use of chains and without the operator having to get off the tractor.

it consitsts of an upside down T shaped frame on which is mounted two movable arms. The arms are mounted on the top and the outside edges of the upside down T shape and protrude to the rear of the frame and the the front. The claw arms are horizontal to the frame. The arms are opened and closed by a double acting hydraulic ram mounted at the rear of the T shaped frame, and connected to the arms at their rear most point by rotating steel pins. The arms are connected to the frame by rotating steel pins. There is also a stabilizing bar connected at the bottom and half way along the length of one arm by a steel pin with the other end of the bar connected with a pin to the opposite corner of the frame The claw arms are fitted with internal sliding square tube and the sliding tube is fitted with the claw hanos, the same size as the arms. The sliding tube and the hands are held by steel pins with position adjustments.

The hands can be rotated in four positions as well as being able to be swapped left to right, the hands can be removed completely as can the inner square tubing.

With different implements welded on the hands, the machine can be used to grab almost anything. The claw attachment is used to grab rocks, stumps, logs and trees, a curved steel attachment is used for carrying drums and bags; a spike is used for standing posts in holes. Different attachments can be placed on the sides of the claw hands and rotated to match the use.

The machine is mounted via the T shaped frame to a three point tractor linkage or to a front end loader bucket frame.

The machine's frame is stressed each side of the vertical and also at the bottom and top of the arms where they attach to the frame.

There are three drawings accompanying this application.

In figure one the device is shown as it would appear side on as it would be attached to a tractor, with the hands in place on the arms.

In figure two, the device is shown from the front with the hands removed from the arms.

Figure three shows the invention as described in this application.

Referring to Figure 1, it can be seen that the hand 1 is in place on the hydraulic arm 2 and the drum carrying attachment 3 is facing up while the scarrlfier 4 and the claw attachment is in position for work. The step 6 is use to wedge small diameter logs to enable them to be lifted clear of the ground.

7 and 8 are lugs for attachment to a tractor Referring to figure 2, The stress frame can be seen in 1 and 2 beneath the frame 3. There are also stress supports 4 each side of the frame. The steel pins 5 run through the stress frame at the bottom and also at the top 6 holding between them the frame 3 and the arm 7.

Figure 3 shows the hands I removed from the sliding internal arms 2. It also shows the reinforced steel collars 3 at the ends of the arms and also at the ends of the hands. Positioning holes to allow the hands to be turned or swapped can be seen at 4 and 5. The hydraulic ram 6 can be seen at the tractor end of the machine, and the stabilizing bar 7 can be seen running beneath the arms 8 and 9. The hands 1 show the attachments for grabbing 10 at the position for work, while the pin attachment 11 and the drum carrier 12 are in the resting position.

The scarrifier or hook 13 is in the work position but is pushed out of the way as the machine goes back to grab.

Attachments for the claws hands can be made to suit any agricultural or industrial job. The basic machine frame can be the base for many applications, with the need only to change the hands to perform other tasks rather than change the whole machine.

Apart from the grab, pull, push and lift functions, attachments can be adapted for ploughing raking, scarrifying rippi ng, grading, and scooping.

The machine, when used on a front end loacer frame can pick up poles from a horizontal position and place them vertically It can used to place large diameter posts in holes with out disturbing the edges of the hole.

The basic frame and grab arms can be adapted to an overhead crane operation in industry, eliminating the need for a hookup person and removing the danger of having someone standing beneath or near a heavy object being lifted.

The advantages of this kind of machine are that it does not damage the ground as dragging with chains does, it does not require the operator to get off and on the machine, it allows the object to be reversed and therefore gives a much more accurate placement. It can lift all kinds of objects, no matter what the material by having the appropriate attachment on the hands. It improves safety by eliminating the need for a second person to guide heavy objects being carried, and it allows and operator to change implements by simply turning the hands on the arms or changing the hands for another set.