Woodworking machines including conductive cutters adapted to cut workpieces, and motors adapted to drive the cutters are disclosed. The machines also include a contact detection system adapted to detect contact between a person and the cutter, and to distinguish contact between the person and the cutter from contact between the workpiece and the cutter. The machines further include a reaction system adapted to cause a predetermined action to take place upon detection of contact between the person and the cutter by the contact detection system.

Detection system for power equipment

A saw with a safety system is disclosed. The safety system includes a detection system adapted to detect contact between a person and a blade while the blade is moving. The safety system further includes a brake system adapted to engage the blade and to stop the blade when the detection system detects contact between the person and the blade.

Safety systems for power equipment

A miter saw is disclosed having a base, a blade supported by the base, a detection system adapted to detect a dangerous condition between a person and the blade, and a reaction system associated with the detection system to cause a predetermined action to take place upon detection of the dangerous condition. The blade is rotatable, and moves into a cutting zone to cut a workpiece. The predetermined action may be to stop the blade from rotating, to create an impulse against movement of the blade into the cutting zone, or to cause the blade to move away from the cutting zone.

Miter saw with improved safety system

Improved methods to detect when a human body contacts a predetermined portion of a machine are disclosed. The methods distinguish contact with a person from contact with other materials. The methods are particularly applicable in woodworking equipment such as table saws to distinguish contact between a person and the blade of the saw from contact between the blade and wet or green wood.

Detection systems for power equipment

Woodworking machines are disclosed having a blade adapted to cut workpieces, and an actuating mechanism operable to move the blade toward the workpiece. The machines also include a detection system configured to detect one or more dangerous conditions between a user and the blade, and a reaction system configured to stop the movement of the blade toward the user upon detection of a dangerous condition by the detection system.

Translation stop for use in power equipment

The device for braking an electric drive motor of a hand-held working tool has a safety brake for an immediate stopping of the working tool and an independent mechanical brake for coasting the working tool to a stop after switching off the drive motor. The mechanical brake acts on a rotational part connected to the drive motor and is activated when a switch element for activating the drive motor is released.

Brake system with two independent mechanical brakes

Braking systems known hitherto for hand-held tools, in particular for portable electric chain saws, comprise a mechanical safety brake which is susceptible to wear and an electrical coasting brake which has complicated circuitry. The novel braking device provides, as coasting brake, a coasting brake which works purely mechanically, is constructionally simple to realise and inexpensive (cost-effective) and has a high functional reliability. The coasting brake is a brake which acts mechanically on a rotational part and is capable of being actuated by releasing a switch lever for starting the drive motor. The mechanical two-circuit braking system is particularly well suited to installation in electrically operated hand-held tools, in particular chain saws.

Mechanical two-circuit braking system

L'invention concerne un dispositif pour le freinage d'un moteur de commande electrique dans une machine-outil guidee manuellement Des dispositifs connus de ce genre, en particulier pour scies a moteur a chaine electriques portables, sont constitues par un frein de securite mecanique et un frein a action progressive electrique techniquement complique au niveau du câblage Afin de creer un frein a action progressive peu couteux et dont la construction est simple a realiser il est prevu un frein (3) qui agit mecaniquement sur un element rotatif, ou tambour de frein, (26) et peut etre actionne par lâchage d'un levier de commutation destine a la mise en marche du moteur de commande

Dieter Wieland

Papers

Brake system with two independent mechanical brakes

Mechanical two-circuit braking system

Dispositif de freinage mécanique à deux circuits.