GB1571767A

GB1571767A - Current supply device for electric gardening appliances

Info

Publication number: GB1571767A
Application number: GB15662/78A
Authority: GB
Original assignee: Wolf Geraete GmbH
Current assignee: Wolf Geraete GmbH
Priority date: 1977-04-21
Filing date: 1978-04-20
Publication date: 1980-07-16
Also published as: FR2388431B1; FR2388431A1; ES235509Y; NL7804178A; CH628860A5; ZA782208B; ES235509U

Abstract

The cable reel device is used for supplying loads which are driven by a motor which is supplied with low voltage, especially hand-operated grass shears. A mains power supply unit (32), which converts the mains voltage to the load supply voltage, is installed in the centre in the cable reel device, which has a drum (10). <IMAGE>

Description

(54) CURRENT SUPPLY DEVICE FOR ELECTRIC GARDENING APPLIANCES (71) We, WOLF-GERATE GMBH, of Gregor-Wolf-Strasse, 5240 Betzdorf, Federal Republic of Germany, a company organised and existing under the laws of the Federal Republic of Germany, 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: The invention relates to a device for supplying electrical power to garden appliances operated with low voltages, in particular electric grass shears. Such grass shears driven by an electric motor have come into extensive use.

The power source is a rechargeable battery fixedly or removably incorporated in the housing. Modern batteries provided for this purpose have a considerable capacity peneitting the shears to be used for extended periods of time.

Nevertheless, it is necessary to be able to supply to such garden appliances from the mains supply independently of rhe battery, firstly because recharging of the battery takes several homos and during this time the shears cannot be used and secondly because the batteries have only a limited life, in particular when they are not properly treated, and the acquisition of new batteries is rather expersive.

Generally, rhe charging units for grass shears do not permit operation from the mains, firstly because the current provided by the charging unit is small compared with the strength of the current passing through the motor. In addition, the conventional charging units cannot be used as mains units because the connec- tion cables are too short and the charging unit itself is not suitable for operation in the open ajar.

The problem underlying the invention is to provide a handy mains unit in particular for electric grass shears which permits operation of the shears from the domestic mains According to rhe invention, this problem is solved in that the mains unit is accommodated in a cable drum onto which at least the low voltage cable provided with the connection may be wound. According to a preferred embodiment of the invention, however, in addition to the low voLtage cable a mains cable may be wound onto rhe cable drum, onto a separate drum portion. The mains unit is so designed that it delivers the power necessary for operating the electric motor. In this manner, after unwinding the cable or cables the shears may be operated in the open air, nevertheless employing the safe low voltage because the shears are connected from the cable drum comprising the mains voltage connection via a relatively long low voltage cable. The cable drum itself may be made relatively simply with safety insula- tion so that it may even be set up in wet grass or even employed in rain without danger.

The drum itself is preferably constructed with hand grips which serve s3xrLultaneously as cable guide in that a guide sleeve halving funnel-like entrance and exit is inserted into the grip. The appliance connection of the low voltage cable may be made in knawn manner as plug which is insertable into correspondingly formed sockets of the grass shears. However, the invention is preferably used in combination with grass shears in which the batteries are arranged in the fonm of a replaceable "power pack" which is so constructed that it cuban be inserted firstly into grass shears and secondly also into spraying appliances or other electrically operated garden tools. To enable the mains unit constructed according to the invention to be used in conjunction with such gardening appliances operable with such a power pack", instead of the connection plug on the low voltage cable a housing is provided which corresponds in its connection dimensions and the electrical connections to the dimensions of the conventional "power pack" so that the connection housing can be replaced by such a power pack and all appliances for which the power pack is suitable can also be driven by the mains unit.

Hereinafter an example of embodiment of the invention will be explained with the aid of the drawings, wherein: Fig. 1 is a perspective view of a current supply device constructed according to the invention in the form ob a cable drum; Fig. 2 is a section along the line Il-Il of Fig. 1; Fig. 3 is a perspective view of grass shears provided with a "power pack"; Fig. 4 is a perspective view of a connection housing corresponding to the power pack of Fig. 3 and forming the appliance connection of the low voltage cable.

The cable drum according to Figs. 1 and 2 comprises a first winding body 10 for coiling the low voltage cable 12 and a second winding body 16 separated from the first by a flange 14 for the mains cable 18. The bodies 10 and 16 are covered laterally by covering flanges 20 and 22 respecavely. At two dliametrlcaloy opposite sides the cable drum is provided with grips 24 and 26 into which guide sleeves 28 with widened entrance and exit are incorporated through which the low voltage cable 12 and the mains cable 18 are led respectively.

The centre flange 14 is provided with a cylindrical extension 30 which faces the edge of the flange 20 leaving an inserting slot through which the low voltage cable can be coiled onto the body 10 or unwound therefrom.

In the space enclosed by the cylindrical winding body 10, which is closed in the axial direction by flange 14 and the cover flange 20, the mains unit 32 is incorporated and includes a transformer and a rectifier. The cables 12 and 18 are introduced into the space accommodating the mains unit through sealed bores of the winding bodies, said space being hermetically sealed outwardly.

The mains plug 34 and/or the appliance connector plug 36 may be introduced when out of use into the holes of the cover 22.

According to the example of embodiment of Figs. 1 and 2 the low voltage cable 12 is also provided with a plug 36 which is adapted to be inserted into a corresponding socket 36 of the shears 40.

According to a further example of embodiment of the invention the mains unit constructed according to the invention is however to be employable in conjunction with garden appliances which comprise an interchangeable "power pack" in the form of an L-shaped housing portion 42 accommodating the batteries and usable not only in conjunction with grass shears but also in conjunction with other garden tools, for example spraying appliances, the housing shapes of which are matched so that the housing portion 42 is inseritable. On insertion of the housing portion provided with batteries into the housing electrical contact is automatically established. The socket member 38 illustrated in Fig. 3 serves in such battery packs generally only for connecting a charging unit end is not suitable for direct connection of a mains unit. For this reason, the appliance connection is preferably constructed not as plug 36 but as housing member 44 which corresponds in form as regards the contact connections to the housing portion 42 accommodating the batteries. The two housing portions 42 and 44 are then interchangeable so that both the garden shears and other corresponding garden or domestic appliances may be operated selectively by battery or from the house mains.

The cable drum as a whole is made from insulating plastic so that it can be handled without danger atthough the mains connection is present within the sealed interior.

WHAT WE CLAIM IS: 1. Device for supplying electrical power to garden appliances operated with low voltage, in particular electric grass shears, characterized in that a mains electric unit (32) thereof is accommodated in a cable drum thereof onto which the low voltage cable (,12) of the unit provided with the appliance connection (36; 44) is coiled.

2. Device according to claim 1, characterized in that the cable drum comprises axially adjacent winding bodies (*10; 16) separated from each other by a flange (14) for the low voltage cable (12) on the one hand and the mains cable (18) on the other which are closed by covering flanges (20; 22).

3. Device according to claim 2, characterized in that the cover flanges (20; 22) engage over the winding space in pot-manner.

4. Device according to claims 1 and 2, charactesized in that the flange (14) comprises an outer cylindrical extension (30) which faces the edge of the covering flange (20) leaving a winding slot.

5. Device according to claims 1 to 4, characterized in that the mains unit (32) is accommodated within the cylindrical winding body (10) for the low voltage cable (12).

6. Device according to claim 5, characterized in that the space accommodating the mains unit (32) and the cable guides are hermetically sealed.

7. Device according to claims 1 and 2, characterized in that the cable drum comprises at two diametrically opposite points hand grips (24; 26) which are formed on the cylindrical portion (30).

8. Device according to claim 7, characterized in that the grips (24; 26) comprise guide sleeves (28) for passage of the mains cable (18) and of the low voltage cable (12).

9. Device according to claim 8, characterized in that the guide sleeves (28) are widened in funnel-like manner at both ends.

10. Device according to any one of claims 1 to 9, characterized in that the appliance connection of the low voltage cable (12) is constructed as housing portion (44) which has the form of a battery housing (42).

111. Device according to claims 1 to 10, characterized in that one of the covering flanges (20; 22) is provided with insert holes for the mains plug (34) and/or possibly the appliance connection plug (36).

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. Fig. 3 is a perspective view of grass shears provided with a "power pack"; Fig. 4 is a perspective view of a connection housing corresponding to the power pack of Fig. 3 and forming the appliance connection of the low voltage cable. The cable drum according to Figs. 1 and 2 comprises a first winding body 10 for coiling the low voltage cable 12 and a second winding body 16 separated from the first by a flange 14 for the mains cable 18. The bodies 10 and 16 are covered laterally by covering flanges 20 and 22 respecavely. At two dliametrlcaloy opposite sides the cable drum is provided with grips 24 and 26 into which guide sleeves 28 with widened entrance and exit are incorporated through which the low voltage cable 12 and the mains cable 18 are led respectively. The centre flange 14 is provided with a cylindrical extension 30 which faces the edge of the flange 20 leaving an inserting slot through which the low voltage cable can be coiled onto the body 10 or unwound therefrom. In the space enclosed by the cylindrical winding body 10, which is closed in the axial direction by flange 14 and the cover flange 20, the mains unit 32 is incorporated and includes a transformer and a rectifier. The cables 12 and 18 are introduced into the space accommodating the mains unit through sealed bores of the winding bodies, said space being hermetically sealed outwardly. The mains plug 34 and/or the appliance connector plug 36 may be introduced when out of use into the holes of the cover 22. According to the example of embodiment of Figs. 1 and 2 the low voltage cable 12 is also provided with a plug 36 which is adapted to be inserted into a corresponding socket 36 of the shears 40. According to a further example of embodiment of the invention the mains unit constructed according to the invention is however to be employable in conjunction with garden appliances which comprise an interchangeable "power pack" in the form of an L-shaped housing portion 42 accommodating the batteries and usable not only in conjunction with grass shears but also in conjunction with other garden tools, for example spraying appliances, the housing shapes of which are matched so that the housing portion 42 is inseritable. On insertion of the housing portion provided with batteries into the housing electrical contact is automatically established. The socket member 38 illustrated in Fig. 3 serves in such battery packs generally only for connecting a charging unit end is not suitable for direct connection of a mains unit. For this reason, the appliance connection is preferably constructed not as plug 36 but as housing member 44 which corresponds in form as regards the contact connections to the housing portion 42 accommodating the batteries. The two housing portions 42 and 44 are then interchangeable so that both the garden shears and other corresponding garden or domestic appliances may be operated selectively by battery or from the house mains. The cable drum as a whole is made from insulating plastic so that it can be handled without danger atthough the mains connection is present within the sealed interior. WHAT WE CLAIM IS:

1. Device for supplying electrical power to garden appliances operated with low voltage, in particular electric grass shears, characterized in that a mains electric unit (32) thereof is accommodated in a cable drum thereof onto which the low voltage cable (,12) of the unit provided with the appliance connection (36; 44) is coiled.

12. Device for supplying electric power to garden appliances operated with low voltage as herein described with reference ro the drawings.