Apparatus and method for making a rubber finish mixture containing at least one reactive additive

An apparatus for making a finished rubber mixture including at least one reactive additive, said apparatus comprising:

• a tandem mixer including an upper machine for mixing a base mixture and having an upper mixing chamber, and a lower machine including a lower mixing chamber;
• said lower mixing chamber being larger than said upper mixing chamber;
• first and second sets of rotors being disposed in said upper and lower mixing chambers, respectively;
• a loading unit including a loading shaft via which mixture components are introduced into said lower mixing chamber;
• said loading unit further including:
• at least first and second metering devices;
• at least one cutting or preheating unit connected upstream of one of said metering devices;
• and, a first conveyor belt leading to said loading shaft;
• said first metering device having a first conveying unit for transport of mixture components to the first conveyor belt;
• said second metering device having a second conveying unit for transport of crosslinking chemicals to a second conveyor belt that leads to said first conveyor belt;
• and,
• said conveyor belts being configured to be switched on and off automatically so that mixture components weighed in can be held in a “wait position” thereon;
• wherein said upper machine and said lower machine are housed in one structure;
• wherein said base mixture, said mixture components and said crosslinking chemicals are different mixtures;
• and,
• wherein said first metering device and said second metering device enable said mixture components and said crosslinking chemicals to be weighed simultaneously.