Manually fed machine for working on materials, objects and the like, and protective means for such a machine

A working machine for manually fed workpieces, comprising:

• a working tool,
• a feeding area in front of the tool, within which a person's hand is present when feeding workpieces to be worked on to the tool,
• a detector covering at least a section of the feeding area for a contactless detection of treatable and/or processable material or objects,
• the detector comprising at least one set of at least two transmitter diodes, and at least one receiver diode,
• the at least two transmitter diodes emitting radiation towards said section of the feeding area, said radiation being emitted at at least two different transmission wavelengths in the wavelength range between 900 nm and 1500 nm, whereas the at least one receiver diode receives the radiation reflected from the section of the feeding area, and
• a signal evaluation unit connected with the detector for calculating the quotients or differences of the intensities of the reflected radiations received by the receiver diode and the at least two different wavelengths emitted from the transmitter diodes,
• wherein based on the calculating, the signal evaluation unit determines whether the detector detects material or objects to be worked on, and
• wherein the tool can only be activated only if the detector detects material or objects to be worked on.

A protective means for protection or for warning persons against access to danger zones, comprising:

• a detector for a contactless detection of human skin within the area covered by the detector,
• the detector comprising at least one set of at least two transmitter diodes and at least one receiver diode,
• the at least two transmitter diodes emitting radiation towards said area covered by the detector, said radiation being emitted at at least two different transmission wavelengths in the wavelength range between 900 nm and 1500 nm, whereas the at least one receiver diode receives the radiation reflected from the section of the feeding area, and
• a signal evaluation unit connected with the detector for calculating the quotients or differences of the intensities of the reflected radiations received by the receiver diode at the at least two different wavelengths from the at least two transmitter diodes,
• wherein based on the calculation, the signal evaluation unit is adapted to determine whether the detector detects human skin.

A working machine for manually fed workpieces, comprising:

• a working tool,
• a feeding area in front of the tool, within which a person's hand is present when feeding workpieces to be worked on to the tool,
• a detector covering at least a section of the feeding area for a contactless detection of material or objects to be worked on,
• the detector comprising at least one radiation unit and at least one receiver unit,
• the at least one radiation unit emitting radiation towards said section of the feeding area, said radiation being emitted with at least two different wavelengths in the wavelength range between 900 nm and 1500 nm, whereas the at least one receiver unit receives the radiation reflected from the section of the feeding area, and
• a signal evaluation unit connected with the detector for calculating the quotients or differences of the intensities of the reflected radiations received by the receiver unit and the at least two different wavelengths emitted from the radiation unit,
• wherein based on the calculation, the signal evaluation unit determines whether the detector detects material or objects to be worked on, and
• wherein the tool can be activated only if the detector detects material or objects to be worked on.

A working machine for manually fed workpieces, comprising:

• a working tool,
• a feeding area in front of the tool, within which a person's hand is present when feeding material to be worked on to the tool,
• a detector covering at least a section of the feeding area for a contactless detection of human skin,
• the detector comprising at least one radiation unit and at least one receiver unit,
• the at least one radiation unit emitting radiation towards said section of the feeding area, and the at least one receiver unit receives the radiation reflected from the section of the feeding area at at least two different wavelengths in the wavelength range between 900 nm and 1500 nm, and
• a signal evaluation unit connected with the detector for calculating the quotients or differences of the intensities of the reflected radiations received from the receiver unit and the at least two different wavelengths emitted from the radiation unit,
• wherein based on the calculating, the signal evaluation unit determines whether the detector detects human skin, and
• wherein upon the detection of human skin, a protective means is configured to be activated for protection against potential injuries caused by the tool, or the signal evaluation unit determines whether the detector detects workpieces to be worked on, wherein the tool can be activated only if the detector detects workpieces to be worked on.

A working machine for manually fed workpieces comprising:

• a working tool,
• a feeding area in front of the tool, within which a person's hand is present when feeding material to be worked on to the tool,
• a detector covering at least a section of the feeding area for a contactless detection of material or objects to be worked on,
• the detector comprising at least one radiation unit and at least one receiver unit,
• the at least one radiation unit emitting radiation towards said section of the feeding area, and
• the at least one receiver unit receives the radiation reflected from the section of the feeding area at at least two different wavelengths in the wavelength range between 900 nm and 1500 nm, and
• a signal evaluation unit connected with the detector for calculating the quotients or differences of the intensities of the reflected radiations received by the receiver unit and the at least two different wavelengths emitted from the radiation unit,
• wherein based on the calculating, the signal evaluation unit determines whether the detector detects material or objects to be worked on, and
• wherein the tool can be activated only if the detector detects material or objects to be worked on.

A protective means for protecting or warning people against access to danger zones comprising:

• a detector for a contactless detection of human skin within the area covered by the detector,
• the detector comprising at least one radiation unit and at least one receiver unit,
• the at least one radiation unit emitting radiation towards said section of the feeding area, and
• the at least one receiver unit receives the radiation reflected from the area covered by the detector at at least two different wavelengths in the wavelength range between 900 nm and 1500 nm, and
• a signal evaluation unit connected with the detector for calculating the quotients or differences of the intensities of the reflected radiations received by the receiver unit at the at least two different wavelengths from the radiation unit,
• wherein based on the calculation, the signal evaluation unit is adapted to determine whether the detector detects human skin.