GB2559725A

GB2559725A - Hand-operated implement

Info

Publication number: GB2559725A
Application number: GB1622477.6A
Authority: GB
Inventors: Watts Patrick
Original assignee: Multi Tip Designs Ltd
Current assignee: Multi Tip Designs Ltd
Priority date: 2016-12-30
Filing date: 2016-12-30
Publication date: 2018-08-22
Also published as: GB201622477D0

Abstract

A hand-operated implement 2 comprises a leg 4 for supporting and manipulating the hand-operated implement during use, the hand-operated implement further comprising a quick release mechanism 6 for removal of the leg from the hand-operated implement. The implement may be a stump grinder. The quick release mechanism may comprise clamping means comprising a recess 28 provided within the leg and a spigot 30 provided on a shaft 8 of the implement. The recess and spigot may only be fitted together when the leg is substantially parallel to the shaft. Also disclosed is a quick release mechanism and a method of releasing a leg from an implement.

Description

(54) Title of the Invention: Hand-operated implement

Abstract Title: Hand operated implement with quick lease leg (57) A hand-operated implement 2 comprises a leg 4 for supporting and manipulating the hand-operated implement during use, the hand-operated implement further comprising a quick release mechanism 6 for removal of the leg from the hand-operated implement. The implement may be a stump grinder. The quick release mechanism may comprise clamping means comprising a recess 28 provided within the leg and a spigot 30 provided on a shaft 8 of the implement. The recess and spigot may only be fitted together when the leg is substantially parallel to the shaft. Also disclosed is a quick release mechanism and a method of releasing a leg from an implement.

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Cutter Wheel

Guard

Foot anchor

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Hand-operated implement

The present invention relates to a hand-operated implement and particularly to a hand-operated implement for cutting materials having a quick release leg.

According to the invention, there is provided a hand-operated implement comprising a leg for supporting and manipulating the hand-operated implement during use, the hand-operated implement further comprising a quick release mechanism for removal of the leg from the handoperated implement. Advantageously, removal of the leg from the hand-operated implement provides an implement which is lighter in weight, making it easier to carry and thus assisting in transport of the hand-operated implement. Advantageously, removal of the leg reduces the dimensions of the implement such that it is easier to store the machine and/ or to transport the machine, for example, in a car. Advantageously, the hand-operated implement is a lightweight machine, typically weighing less than 25 kg and preferably powered by a chainsaw engine.

Preferably, the hand-operated implement is a stump grinder, preferably a hand-held tree stump grinder.

Preferably, the stump grinder includes a shaft, wherein the leg pivots about the shaft. It is preferred that the leg is provided at approximately the centre of balance along the shaft. Preferably, the leg acts as a pivot point during grinding of the hand-operated implement.

Preferably, the stump grinder comprises a support for supporting the foot of a user. Preferably, the support is provided in the form of a foot anchor.

Preferably, the leg is fitted with a wheel. It is preferred that the wheel is provided at the end of the leg that contacts the ground when the implement is in use. Advantageously, the provision of a wheel assists in manoeuvrability of the implement when in use. Preferably, the foot anchor is attached to the wheel provided on the leg of the implement.

Preferably, the leg is fitted with a spike which may be positioned in the ground during use. Advantageously, the provision of a spike provides a support when the implement is in use, preventing or reducing unwanted movement of the implement during use.

Preferably, the leg is fitted with a pad.

Preferably, the leg is provided with a handle positioned at the end of the shaft nearest the user when the implement is in Use. Advantageously, the provision of the handle allows the user to manipulate the hand-operated implement. Preferably, the provision of the handle allows the user to move the leg backwards and forwards whilst lifting the engine of the implement. In the embodiment wherein the hand-operated is a tree stump grinder, the movement of the leg pushes the spinning wheel into the stump to assist in the grinding of the tree stump.

Preferably, the hand-operated implement further comprises a removable guard. Preferably, the removable guard may be removed from the hand-operated implement via a quick release mechanism. Removal of the guard also advantageously decreases the weight of the tree stump grinder, making it easy to transport and store.

Preferably, the quick release mechanism comprises clamping means, wherein the clamping means preferably comprises a recess provided within the leg and a spigot provided on the shaft of the implement.

Preferably, the clamping means comprises nylon. Advantageously, the use of nylon provides low wear and low friction properties such that the clamping means requires little or no regular lubrication.

According to a second aspect there is provided a quick release mechanism for use with the handoperated implement of the first aspect.

Preferably, the clamping means comprises nylon. Advantageously, the use of nylon provides low wear and low friction properties such that the clamping means requires little or no regular lubrication. Preferably, the spigot and portion of the leg comprising the recess comprise nylon.

According to a third aspect, there is provided a method of releasing a leg from a hand-operated implement according to the first aspect of the invention by means of a quick release mechanism according to the second aspect of the invention.

Preferably, the recess provided on the leg and spigot provided on the shaft can only be fitted together when the leg is in a configuration such that it is substantially or almost parallel to the shaft. In this configuration, it would not be possible to operate the hand-operated implement. Preferably, once the recess and spigot have been fitted together, the handle is typically pulled backwards into the working position where it can’t be disconnected from the leg. Advantageously, the provision of a clamping means in accordance with the invention improves the safety of the device, since the leg cannot be removed from the handle in the working configuration.

According to a fourth aspect, there is provided a method of grinding a stump comprising the step of using apparatus as defined hereabove.

The invention will be further described by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a schematic perspective view of a hand-operated implement according to an embodiment of the invention;

Figure 2 is a side plan view of a hand-operated implement according to an embodiment of the invention;

Figure 3 is a perspective view of part of the shaft of a hand-operated implement according to an embodiment of the invention; and

Figure 4 is a perspective view of part of the leg of a hand-operated implement according to an embodiment of the invention according to an embodiment of the invention;

With reference to the drawings, there is provided a hand-operated implement 2 comprising a leg 4 for supporting and manipulating the hand-operated implement during use, the hand-operated implement further comprising a quick release mechanism 6 for removal of the leg from the hand4 operated implement. Advantageously, removal of the leg from the hand-operated implement provides an implement which is lighter in weight, making it easier to carry and thus assisting in transport of the hand-operated implement. Advantageously, the hand-operated implement is a lightweight machine, typically weighing under 25 kg and powered by a chainsaw engine. Advantageously, removal of the leg reduces the dimensions of the implement such that it is easier to store the machine and/ or to transport the machine, for example, in a car.

In the embodiment shown in Figure 1, the hand-operated implement is a hand-held tree stump grinder. The stump grinder includes a shaft 8, wherein the leg 4 pivots about the shaft. The leg is typically provided at approximately the centre of balance along the shaft. Advantageously, the leg acts as a pivot point during grinding of the hand-operated implement.

The stump grinder comprises a support 10 for supporting the foot of a user. In this embodiment, the support is provided as a foot anchor 10.

In the embodiment shown in Figure 1, the leg 4 is fitted with a wheel 12. In this embodiment, the wheel 12 is provided at the end of the leg 4 that is furthest from the user when the implement is in use. Preferably, the wheel 12 is provided at the end of the leg 4 that contacts the ground. Advantageously, the provision of a wheel 12 assists in the manoeuvrability of the implement when in use.

In one embodiment, the leg 4 may be fitted with a spike 14 which may be positioned in the ground during use. Advantageously, the provision of a spike 14 may improve the stability of the device when it is in use, wherein the spike anchors the implement to the ground, reducing and/ or preventing unwanted movement of the implement during use.

In one embodiment, the leg may be fitted with a pad 16.

In the embodiment shown in Figure 1, the leg 4 is provided with a handle 18 positioned at the end of the shaft 8 nearest the user when the implement is in use. Advantageously, the provision of the handle 18 allows the user to manipulate the hand-operated implement. Preferably, the provision of the handle 18 allows the user to move the leg 4 backwards and forwards whilst lifting the engine 20 of the implement. In the embodiment wherein the hand-operated is a tree stump grinder, the movement of the leg 4 pushes the spinning cutter wheel 22 into the stump to assist in the grinding of the tree stump. The bottom of the leg 4 is supported by the operator when grinding.

The hand-held implement may further comprise a guard 24 which preferably comprises a flexible material such as polycarbonate. Advantageously, the guard may be replaceable at low cost.

Typically, the hand-operated implement comprises a removable guard 24. The removable guard 24 may be removed from the hand-operated implement via a quick release mechanism. Removal of the guard 24 also advantageously decreases the weight of the tree stump grinder, making it easy to transport and store. Advantageously, the guard 24 may be removed from the implement in a matter of seconds.

With reference to Figures 3 and 4, the quick release mechanism 6 comprises clamping means 26,’ wherein the clamping means preferably comprises a recess 28 provided within the leg 4 and a spigot 30 provided on the shaft 8. The quick release leg has a clamping system with a simple location hole or recess 28 that locates precisely with the spigot 30 on the main shaft. The system can only be fitted together when the leg is almost parallel to the shaft. It wouldn’t be possible to operate the machine in this position. Once the parts have been fitted together, the handle is pulled backwards into the working position where it can’t become disconnected until the handle is pushed all the way forward again. Both parts are fitted snugly and both are preferably made from nylon which has excellent, low wear and low friction properties, requiring little or no lubrication.

Thus, preferably, the clamping means 26 comprises nylon. Advantageously, the use of nylon provides low wear and low friction properties such that the clamping means requires little or no regular lubrication.

In the embodiment shown in the figures, the hand operated implement comprises a drive mechanism comprising a driving sprocket to drive a rotatable workpiece and at least one intermediate sprocket of different diameter to the driving sprocket to allow for variation of speed and torque of the rotatable workpiece.

The hand-operated implement is advantageously a lightweight machine, typically weighing under 25kg and powered by a chainsaw engine.

The machine consists of a cutter wheel with teeth which is mounted onto a stub shaft which is fitted into a hub with roller bearing support. Off the other end of the stub shaft, within the hub is a pulley wheel.

The hub is attached to a hollow, rectangular tube which contains a series of stepped, floating, pulleys connected by separate belts. This provides the reduction in gearing from the engine to the cutter wheel. The engine RPM is around 12,000 and the required speed for the cutter wheel is around 3,000.

The belts are tensioned at the engine end of the shaft but not using the engine. The assembly is pre-tensioned before fitting the engine.

As the series of pulleys are floating within the shaft, they can all be tension together equally.

The pulleys are mounted onto the floating pulley holders with a bearing and held tightly in place onto the floating holder with a bolt.

The pulley holders will fit snuggly within the shaft with free movement in only one axis until the belts are tensioned. A single bolt pulls the pulley holder nearest to the engine end, which in turn pulls the next pulley, which pulls the third floating pulley, which tightens up the whole assembly because the final pulley wheel that is in the hub is not floating.

More pulley wheels can be added if necessary to reduce the final speed further, which might be required for other applications.

The engine is then attached to the shaft and there is another belt between the engine pulley and the first pulley within the shaft. This is tensioned separately by pushing the engine away from the end of the shaft.

In use, the operator wheels the machine to the tree stump, puts his foot on the bottom of the leg and proceeds to cut slices out of the stump using the handle on the top of the leg to push the machine forward whilst raising the engine with his right hand. His right hand adjusts the throttle control accordingly.

Thus, the present invention preferably relates to a floating pulley system within the shaft of a hand-operated implement with easy tensioning.

Some of the advantages of the invention are that the hand-operated implement is typically lighter in weight and less expensive than previous hand-operated implements comprising a drive means; the implement comprises a quick release handle; may allow for easy belt tensioning; may allow a user to swap with a chainsaw blade in seconds; may allow for a quick change when using with a high performance multi-tip system; may allow for variable gearing for different engines; may comprise a wheel 12 on the leg of the hand-held implement for easy manoeuvrability. The wheel 12 may comprise a foot support 10.

The present invention advantageously provides a system where the speed may be reduced with a number of stepped pulleys. The belts within the machine Can advantageously be pre tensioned before fitting the engine, allowing for very quick changing of the engine such that the user can switch from stump grinder to chainsaw blade in two or three minutes.

With reference to the figures, there is further provided a quick release mechanism 6 for use with the hand-operated implement of the first aspect. The quick release mechanism comprises clamping means 26, wherein the clamping means comprises a recess 28 provided within the leg and a spigot 30 provided on the shaft 8 of the implement 2.

With reference to the figures, there is provided a method of releasing a leg 4 from a handoperated implement 2 according to the first aspect of the invention by means of a quick release mechanism 6 according to the second aspect of the invention.

In use, the recess 28 provided on the leg 4 and spigot 30 provided on the shaft 8 can only be fitted together when the leg 4 is in a configuration such that it is substantially or almost parallel to the shaft 8. In this configuration, it would not be possible to operate the hand-operated implement. Preferably, once the recess and spigot have been fitted together, the handle 18 is typically pulled backwards into the working position where it can’t be disconnected from the leg

4. Advantageously, the provision of a clamping means 26 in accordance with the invention improves the safety of the device, since the leg 4 cannot be removed from the handle 18 in the working configuration.

With reference to the figures, there is provided a method of grinding a stump comprising the step of using apparatus as defined hereabove.

Claims

1. A hand-operated implement comprising a leg for supporting and manipulating the handoperated implement during use, the hand-operated implement further comprising a quick release mechanism for removal of the leg from the hand-operated implement.

2. A hand-operated implement according to claim 1, wherein the hand-operated implement is a stump grinder.

3. A hand-operated implement according to claim 1 or 2, wherein the stump grinder includes a shaft, wherein the leg pivots about the shaft.

4. A hand-operated implement according to any preceding claim, wherein the leg acts as a pivot point during grinding.

5. A hand-operated implement according to any preceding claim, wherein the stump grinder comprises a support for supporting the foot of a user.

6. A hand-operated implement according to claim 5, wherein the support is provided in the form of a foot anchor.

7. A hand-operated implement according to any preceding claim, wherein the leg is fitted with a wheel.

8. A hand-operated implement according to any one of claims 5 to 7, wherein the support is attached to the wheel provided on the leg of the implement.

9. A hand-operated implement according to any preceding claim, wherein the leg is fitted with a spike which may be positioned in the ground during use.

10. A hand-operated implement according to any preceding claim, wherein the leg is fitted with a pad.

11. A hand-operated implement according to any preceding claim, wherein the leg is provided with a handle positioned at the end of the shaft nearest the user when the implement is in use.

12. A hand-operated implement according to any preceding claim, further comprising a removable guard.

13. A hand-operated implement according to claim 12, wherein the removable guard may be removed from the hand-operated implement via a quick release mechanism.

14. A hand-operated implement according to any preceding claim wherein the quick release mechanism comprises clamping means.

15. A hand-operated implement according to claim 14, wherein the clamping means comprises a recess provided within the leg and a spigot provided on the shaft of the implement.

16. A hand-operated implement according to any preceding claim, wherein the clamping means comprises nylon.

17. A quick release mechanism for use with the hand-operated implement according to any one of claims 1 to 16.

18. A quick release mechanism according to claim 17 comprising clamping means.

19. A quick release mechanism according to claim 17 or 18, wherein the clamping means comprises a recess provided within the leg and a spigot provided on the shaft of the implement.

20. A quick release mechanism according to any one of claims 17 to 19, wherein the clamping means comprises nylon.

21. A method of releasing a leg from a hand-operated implement according to any one of claims 1 to 16 by means of a quick release mechanism according to any one of claims 17 to 20.

22. A method according to claim 21, wherein the recess provided on the leg and spigot provided on the shaft can only be fitted together when the leg is in a configuration such that it is substantially or almost parallel to the shaft.

23. A method according to claim 22, wherein once the recess and spigot have been fitted together, the handle is typically pulled backwards into the working position where it can’t be disconnected from the leg.

24. A method of grinding a stump comprising the step of using apparatus as defined hereabove.

25. A hand-operated implement as defined herein and with reference to the accompanying drawings.

26. A quick release mechanism as defined herein and with reference to the accompanying

5 drawings.

27. A method of releasing a leg from a hand-operated implement as defined herein and with reference to the accompanying drawings.

Intellectual

Property

Office

Application No: GB 1622477.6