For several years now, INTERBUS has been helping to increase the efficiency of the production systems in various Ford plants.
Ford was prompted to choose INTERBUS for its worldwide projects as well, not just because of the possible investment savings but also as a result of the positive experience with plant availability.
Examples of new projects include the new automatic assembly systems in the plants at Lima in the U.S.A. and Dagenham near London.
Thanks to the INTERBUS Loop,
it has been possible to
dispense with switch cabinets
completely in this transport system
At its plant in Lima, Ohio, Ford is currently building the production systems for the new 3.9 liter V8 engine with 4-valve technology to be used in top-of-the-range limousines. Technically speaking, this is based on an engine from Ford's subsidiary Jaguar - an engine which is already being produced with the help of INTERBUS. The first engines are due to come off the production line in Lima at the end of 1997. Here too, the use of INTERBUS has already paid off: thanks to INTERBUS, it has been possible to dispense with more than 60% of the switch cabinet area which would have been required otherwise, principally due to the more efficient cabling used.
The project at the Dagenham plant is the most recent of Ford's INTERBUS projects. They are building the very systems which are to produce the new generation of four cylinder diesel engines for mid-range automobiles. In this factory, it is not just the engines being produced which reflect the technical standards of tomorrow; the production systems are also pointing the way ahead. Thanks to the new installation technology of the INTERBUS loop and new programmable controllers, it has proved possible to set up these systems entirely without switch cabinets for the first time.
The decentralized power
supply unit supplies electrical
power to the machines
This innovative step has been made possible by the small RFC controllers with IP 54 protection which are bolted directly onto the machine frame, as well as by the high-performance PC cards which "disappear" directly into the control devices. The controllers are referred to as Soft PLCs and are implemented on industrial PCs. They are connected to the sensor and actuator systems by the INTERBUS loop with the IP 65 I/O modules.
INTERBUS-capable motor control switches control the individual drives locally to enable the engines to be passed on from one assembly station to the next within the transport system. In this process, all data relevant to production are conveyed in the chassis by an ID system provided by Euchner + Co. of Leinfelden-Echterdingen, Germany. The CNC functions in the assembly stations are provided by an Indramat PC card which has been specially optimized for use in the handling area.
Thus, for the first time, Ford has equipped its production systems with an open platform for the controller as well as the open peripheral device interface, INTERBUS. On the one hand, both fulfill all the technical requirements and, on the other, they are free from the domination of the big manufacturers of automation equipment. In addition to the familiar advantages of the sensor and actuator buses such as savings in cabling and during commissioning, the two standards - "INTERBUS and PC" - make it possible to select the optimum equipment from any manufacturer and to integrate it into a high-performance automation system whilst making use of
all the features.
Dipl.-Ing. Burkhard Werner