The invention relates to an assembly associated with manufacturing a production cell and particularly to altering the production cell when the op- eration stages in the production cell change, for example, when the product to be manufactured in the production cell changes. Such a change often requires that at least some of the actuators in the production cell are changed. How- ever, the production apparatus, or the robot, in the cell is not changed in such situations but is merely reprogrammed so as to be able to co-operate with new actuators.

In prior art production cells individual actuators are attached to the production cell frame, in which case the change thereof requires each individ- ual actuator to be separately detached and changed. Such a change of ac- tuators is extremely laborious and slow. Furthermore, the production cell frames are generally tailor-made in order to conduct a particular production stage, whereby the frames intended to conduct different production stages generally differ from one another. Thus, in some cases, it may be impossible to change a particular production cell in such a manner that it could be used to conduct another production stage, because the actuators needed to perform said second production stage cannot be arranged to the frame.

If, however, it is possible to change the actuators in the production cell, a drawback is in general associated with prior art production cells that the function thereof must be tested before starting actual production. It is then en- sured during the test stage that the production apparatus and the new actua- tors of the production cell can co-operate, as desired, ensuring at the same time that the positions of the actuator in reality correspond with the presumed positions which are programmed into the production apparatus (otherwise the production apparatus may, for example, collide with the actuator). Carrying out the test stage further delays the production cell change.

The idea of the invention is to solve the problems described above and to provide a production cell which can be changed in a significantly sim-

pler and faster way than prior art production cells. This aim is achieved with a production cell of the invention, characterized by the production cell compris- ing at least two alternative actuator modules, both of which being provided with actuators needed for a particular production stage, said frame and said at least two actuator modules being provided with first locator elements control- ling the actuator module mounted to the frame into a predetermined position regarding the frame, and a first interface being arranged to the frame for con- necting the actuators of the actuator module mounted to the frame to the con- trol unit, whereby the control unit controls the production apparatus and the actuators of the actuator module mounted to the frame to co-operate in order to conduct the production stage to be performed in the production cell.

The invention is based on the idea that standardizing the shape of the production cell frames and assembling the actuators used in the produc- tion cell to interchangeable actuator modules significantly facilitate and speed up the production cell change. All the actuators of the production cell can then be changed at the same time by changing the entire actuator module. When the production cell frame and actuator modules are provided with locator ele- ments the actuator modules can directly be mounted into a proper position of the frame, thus ensuring that the positions of the actuators assumed in pro- gramming the production apparatus are correct. Hence, the need to carry out a separate test stage is avoided. The compatibility of the actuators and the production apparatus can also be ensured by connecting the actuators through the interface in the frame to the control unit of the production appara- tus. The same control unit thus controls both the actuator and the production apparatus. The actuator module may also comprise a specific control unit.

However, the control unit of the production apparatus attends to the highest level control ensuring the compatibility of the production apparatus and the actuators.

In a preferred embodiment of the production cell of the invention said at least two actuator modules comprise a memory means in which data needed to identify the actuator modules is stored. Then the control unit com- prises means for identifying the actuator module on the basis of the data stored in the memory means, when the actuator module is connected to the control unit, and means for retrieving a programme stored in said memory concerning the identified actuator module and controlling the production appa- ratus and the actuators of the actuator module in accordance with said pro-

gramme. This embodiment of the invention still further speeds up the actuator module change in the production cell. Since the control unit can independently identify the actuator module and retrieve for it a programme previously stored in the memory, the actuator module change does not require programming operations when changing the actuator module. It is therefore enough to mount the actuator module to the frame and connect it to the control unit, whereafter the production cell is ready for a new operation stage.

The preferred embodiments of the production cell of the invention are disclosed in independent claims 2 to 3.

In the following the invention will be described in greater detail by way of example by a preferred embodiment with reference to the accompany- ing drawings, in which Figure 1 shows a production cell before an actuator module and a conveyor are mounted, and Figure 2 shows a production cell ready for use.

Figure 1 shows a production cell before an actuator module and a conveyor are mounted. The production cell in Figure 1 comprises a frame 1, a thereto attached four-dimensional production apparatus 2, which can be formed of a robot (the robot can alternatively also be, for example, two or three-dimensional). For controlling the robot 2 a control unit 3 is arranged to the frame comprising a memory 4. A user interface 5 is also connected to the control unit 3.

A free surface 6 is arranged to the frame 1 for receiving actuators of the production cell. Locator elements 7, formed of pins in Figure 1, protrude from said surface. An actuator module 8 to be mounted to the frame also comprises locator elements 9 (apertures in Figure 1), which are counterparts of the locator elements 7 in the frame 6. The locator element control thus en- ables the actuator module 8 to be accurately mounted into a predetermined position on the surface 6 of the frame 1.

A conveyor 10 including accessories (such as a stopper, centralizer and sub-response) is also mounted on the surface 6 of frame 1. For this pur- pose, second locator elements 11 are arranged on the surface 6. The con- veyor can thus be accurately mounted into a predetermined position on the surface 6 due to the control of the locator elements 11 of the frame 1 and the locator elements 12 of the conveyor.

It is therefore very simple to mount the conveyor 10 and the actua-

tor module 8 to the frame 1, since the location thereof is directly determined by the position of the locator elements. When the conveyor 10 and the actuator module 8 have been lifted into position on the surface 6 they can be attached into position with only a few screws that prevent them from moving when the production cell is used.

An interface 13 is arranged to the frame 1. After mounting the ac- tuator module 8 into position the interface 13 is connected to a counterpart 14 (shown in Figure 2) in the actuator module. The actuators of the actuator module 8 can thus be connected to the control unit 3 of the production cell.

Correspondingly the frame 6 comprises an interface 15 which is connected to a counterpart 16 in the conveyor. The conveyor is thus also connected to the control unit 3. All electrical connections of the actuator module and corre- spondingly the conveyor can therefore be conducted through a single inter- face. The actuator module 8 may comprise a specific control unit for controlling the actuators therein, but it is the control unit 3 of the production apparatus that attends to the highest level control ensuring the compatibility of the pro- duction apparatus 2 and the actuators.

If, for example, compressed air is needed in the actuator module 8 and/or the conveyor, the frame 6 may comprise an interface to a compressed air source. Then the actuator module and/or the conveyor are provided with a compressed-air hose, which is attached to the interface in the frame. There- fore cords/hoses to be connected to the actuator or the conveyor from outside the production cell are not needed, instead all the cords/hoses to be con- nected to the conveyor or the actuator module are drawn from the production cell frame.

Figure 2 shows a production cell ready for use. In Figure 2 the ac- tuator module 8 and the conveyor 10 of Figure 1 are mounted and attached into position in the frame 1. In addition, all cords and hoses needed are con- nected to them. Then, the user of the production cell activates the control unit 3 of the production cell through a user interface 5.

When the control unit 3 of the production cell is activated, it identi- fies at first the actuator module 8 mounted thereto. In this case, each actuator module 8,18,28,38 that can be mounted to the frame 1 comprises a memory means (for example in the counterpart, i. e. the cable connector 14) in which an identifier intended to identify the actuator module is stored. The control unit 3 thus reads the identifier from the actuator module 8.

When the control unit has identified the actuator module 8 it re- trieves from the memory 4 the programme stored therein for said actuator module. The conveyor 10 may also comprise a corresponding memory that allows the control unit 3 to identify the conveyor. The production cell is thus ready for use as soon as the control unit 3 thereof has retrieved the correct programme from the memory 4. Then, the control unit 3 is ready to start to control the production apparatus 2, the actuators of the actuator module 8 (for example through the specific control unit of the actuator module) and the con- veyor 10 as programmed for conducting the production stage determined by the programme. No separate test sequence is needed since the locator ele- ments have accurately determined the positions of the actuators and the con- veyor and production can be started immediately.

Figure 2 shows a rack 19, in which three alternative actuator mod- ules 18,28,38 are arranged that can all be mounted to the production cell frame 1 using a forklift 17. All said production modules comprise counterparts 14 in which data is stored enabling the control unit 3 to identify them, and thereafter to retrieve a programme regarding the modules stored in the mem- ory. Correspondingly there may be several conveyors, for example, for con- veying products of various shapes.

Actuators arranged to the actuator modules can in principe consist of any prior art actuators. For example: -a router used to detach circuit boards attached together in a panel that the conveyor brings to the production cell, -a label assembly device attaching a label on the circuit board that the conveyor brings to the production cell, -a component assembly device assembling electrical components on the circuit board that is brought to the production cell.

The actuator modules may also comprise tool houses for the pro- duction apparatus 2. The production apparatus may thus search for a tool in- tended for a particular production stage from the actuator module tool house and return it after the operation stage.

The production cell of the invention enables implementation of new production stages within a very short time. By using standard frames 1 in pro- duction cells a new operation stage can easily be"initiated"in another produc- tion cell, or test cell, than where the actual production will take place. Then, the actuators needed in the new production stage are assembled to a new

actuator module, which is mounted to the test cell, where the programming and testing required by the operation stage are conducted. When the new production stage operates satisfactorily in the test cell the new actuator mod- ule can be mounted to the actual production cell. Then, also the programme accomplished in the test cell is stored in the memory arranged at the control unit of the production cell. Since the frame of the production cell and the test cell and the production apparatus are identical, production can thereafter be started immediately in the production cell. The production cell has thus "stopped"for a very short time despite a completely new production stage or product.

It should be understood that the above description and the drawings associated therewith are merely intended to illustrate the invention. Different variations and modifications of the invention will be obvious for those skilled in the art without deviating from the scope and the spirit of the invention set forth in the attached claims.