GARDENING IMPLEMENT

Abstract: A hand held powered gardening implement is described that comprises a prime mover (10) fitted with a first handgrip, a drive shaft (18) rotated by the prime mover (10), a rigid tube (12) connected to the body of the prime mover (10) and surrounding the drive shaft (18) and incorporating a second handgrip (14), and a tilling and aerating tool (22) releasably secured to the end of the drive shaft (18) remote from the prime mover (10). The tool (22) comprises two prongs that have bent flattened ends (22d, 22e) designed to push the soil away from the axis of rotation of the tool (22) at the same time as lightly urging the tool into the soil.

Description: Gardening Implement Field of the invention This invention relates to a gardening implement and in particular to an implement for tilling and aerating soil. Background of the invention Power tillers, more commonly known as rotary hoes or cultivators, are used to till and aerate the soil. The machines are medium to heavy duty implements and are used in the main by farmers, small holders and professional gardeners. Such machines typically comprise an engine as the power mover and a change speed gear box driving an axle, driven wheels and a rotating shaft with attached flanges and tiller blades. Machines are also known that have no gearbox and in which there are no drive wheels. In this case, the engine is directly linked to the tiller shaft by a chain or belt drive thus providing a forward motion and tilling operation combined. The machines described, whilst being manually operated and controlled, are comparatively heavy in use. The handles attached to the machines enable the operator to direct its forward motion and tilling depth in much the same way as one uses a lawn mower. Whilst walking with and behind the machine the tiller shaft rotates parallel to the ground with either the machine wheels or the tiller shaft and blades always in contact with the ground being tilled. The known rotary hoes or cultivators, apart from being expensive heavy duty items of equipment, are heavy and difficult to control. For this reason, they are not suited for example for turning over the soil in an established flower border of a domestic garden, being too unwieldy for this purpose. US-A-4 , 501, 332 describes a hand carried portable weeder/cultivator that uses an inverted dish-shape as a weeding tool. Such a tool is not effective in turning over soil . GB-A-1, 444, 033 describes a hand held cultivator in which two forked elements are mounted on a plate for rotation in opposite senses about vertical axes. Such a tool stirs the soil and can break it into smaller pieces but it is not effective in turning over the soil. The provision of a head with two elements also makes the cultivator heavy and unwieldy. Object of the invention The present invention seeks to provide a hand held portable powered implement for tilling and aerating soil that is easy to use and effective in turning over the soil and removing weeds . Summary of the invention According to the present invention, there is provided a hand held powered gardening implement comprising a prime mover, a drive shaft rotated by the prime mover, a rigid tube connected to the body of the prime mover and incorporating a handle, and a tilling arid aerating tool releasably secured to the end of the drive shaft remote from the prime mover, the tool comprising a single pair of prongs having flattened ends that are inclined in such a manner as to tend to drag the tool into the soil and to push the soil away from the axis of rotation of the tool. The invention relates to a hand held portable implement in the sense that it is carried by the user in the same way as an electric hedge trimmer rather than its weight resting on the ground and only its direction of movement being determined by the user in the manner of a plough. The prime mover may be either an electric motor or an engine arranged at the upper end of the implement, the tube being a hollow tube surrounding the drive shaf . Because the weight of motor is at the upper end of the implement, this configuration makes for easier operation and control. Preferably, the speed of rotation of drive shaft is variable, for example in the range from 0 to 500 rpm, either by varying the operation of the prime mover or by acting on a change speed gearbox arranged between the prime mover and the drive shaft. The release mechanism between the tilling tool and the drive shaft may comprise a collet, a bayonet fitting with a locking ring, a chuck, a screw and lock nut or any other mechanism capable of transmitting torque to the tool while allowing it to be removed and interchanged. In use, the powered tiller aerator is held using two handgrips and the axis of rotation can be either vertical or inclined to he vertical. When the axis is inclined, rotation of the prongs causes them to throw the soil up in the same way as a conventional rotary hoe having wheels that rotate about a horizontal axis. In operation, the implement is first lifted clear off the ground and the desired speed is selected by a motor switch or finger trigger, setting the tool in rotation. The tool is then urged into the earth being tilled and a prodding action is used to achieve the tilling and aerating. The action of the rotating tool or blade will also remove small weeds in the process. The implement described herein could be operated by most adults as a domestic implement for use on prepared flower beds and borders, shrubberies and vegetable gardens and generally wherever the conventional rotary hoe or cultivator could not operate due to its bulk weight and design configuration. According to a further aspect of the invention, there is provided a tool for use with a powered tilling and aerating implement, the tool comprising a stem to be connected to a drive shaft, a pair of prongs extending from the free end of the stem, each prong comprising a base portion connected to the stem and extending generally parallel to but offset from the stem, an inclined portion extending from the free end of the base portion out of the plane containing the base portions of the two prongs and a flattened end portion at the end of the inclined portion inclined at an angle to the axis of the stem so as to urge the soil away from the direction of rotation of the tool. Brief description of the drawings The invention will now be described further, by way of example, with reference to the accompanying drawings, in which : - Figure 1 shows in perspective a hand held implement of the invention, Figure 2 is a detail showing the design of the aerating and tilling tool, Figure 3 is a front view of the aerating tool, Figure 4 is a side view of the tool in Figure 3, and Figure 5 is an end view of the tool in Figures 3 and . Detailed description of the prpfprre embodiment Referring to the drawings, the hand held tiller aerator comprises a drive motor 10, which may for example be an electric drill, attached to a rigid tube 12 with adjustable grip handle 14. A drive shaf 18 is housed in the rigid tube 12 and projects from under the end of the tube 12. A release mechanism 20 fitted to the free end of the drive shaft permits a tool 22 to be detachably mounted on the drive shaft. A guard plate 16 is fitted to the lower end of the tube 22 to protect the user and prevent clothing from becoming entangled in the rotating tool. The guard also acts to distance the tool from plants so that existing vegetation is not uprooted or disturbed while aerating the surrounding soil . The tool itself is shown in more detail in Figure 2 to 5. The tool has a stem 22a with two bent prongs 22b and 22c mounted at its free end. The ends 22d and 22e of the prongs are flattened and lie at an angle of 45° to the axis of the stem so that they throw out the soil when the tool is rotated and exert a small axial force tending to move the tool into the ground. It is to be emphasised however that the tool should not act as a drill as the aim is not to make holes in the soil but to throw out and agitate the soil to break it up into smaller and finer pieces. The regions of the prongs adjacent the flattened ends are brought into close contact with one another in the manner best seen in Figure 3. This prevents lumps of soil from lodging themselves between the prongs and interfering with the tilling action of the tool. The tool can be conveniently manufactured by forming the two prongs from a bent rod that is later welded to the stem 22a. The ends of the rod can first be bent in opposite senses through an angle of substantially 42°. The bent ends are then flattened by forging to lie at 45° to the plane of the bent rod. Lastly, the rod is folded in two at its centre into the shape shown in Figure 3 and welded to the stem 22a. It will be appreciated that various modifications may be made to the implement within the scope of the invention as set out in the appended claims. For example, it is possible to make the tube 12 and the drive shaft 18 collapsible to allow the implement to be used comfortably by people of different height. Furthermore the motor may be fitted to the lower end of the t

Claims: CLAIMS 1. A hand held powered gardening implement comprising a prime mover (10) , a drive shaft (18) rotated by the prime mover (10) , a rigid tube (12) connected to the body of the prime mover (10) and incorporating a handgrip (14) , and a tilling and aerating tool (22) releasably secured to the end of the drive shaft (18) remote from the prime mover (10) , the tool (22) comprising a single pair of prongs (22b, 22c) having flattened ends (22d, 22e) that are inclined in such a manner as to tend to drag the tool into the soil and to push the soil away from the axis of rotation of the tool. 2. An implement as claimed in claim 1, the prime mover is an electric motor or an engine arranged at the upper end of the implement, the tube being a hollow tube surrounding the drive shaft . 3. An implement as claimed in claim 1 or 2, wherein the speed of rotation of drive shaft is variable. 4. An implement as claimed in claim 3, wherein the speed of rotation of drive shaft is variable in the range from 0 to 500 rpm. 5. An implement as claimed in claim 3 or 4 , wherein the speed of rotation of the drive shaft is variable by varying the operation of the prime mover. 6. An implement as claimed in claim 3 or , wherein the speed of rotation of the drive shaft is variable by acting on a change speed gearbox arranged between the prime mover (10) and the drive shaft (18) . 7. An implement as claimed in any of claims 2 to 6, wherein the release mechanism between the tilling tool and the drive shaft comprises a collet, a bayonet fitting with a locking ring, a chuck or a screw and lock nut. 8. A tool for use with a powered tilling and aerating implement, the tool comprising a stem (22a) to be connected to a drive shaft of the implement, a pair of prongs (22b, 22c) extending from the free end of the stem (22a) , each prong comprising a base portion connected to the stem and extending generally parallel to but offset from the stem, an inclined portion extending from the free end of the base portion out of the plane containing the base portions of the two prongs and a flattened end portion at the end of the inclined portion inclined at an angle to the axis of the stem so as to urge the soil away from the direction of rotation of the tool.

Inventors: THOUPOS ANDREW, THOUPOS, ANDREW
Applicants: THOUPOS ANDREW, THOUPOS, ANDREW
Application year: 1995
Main classification: A01B1
IPC codes: A01B1