WO1988009601A1

WO1988009601A1 - Manually operated surface component assembler

Info

Publication number: WO1988009601A1
Application number: PCT/SE1988/000259
Authority: WO
Inventors: Jan Ruus
Original assignee: Adcam Ab
Priority date: 1987-05-22
Filing date: 1988-05-19
Publication date: 1988-12-01
Also published as: SE8702153L; SE8702153D0; SE461511B

Abstract

A manually operated surface component assembler including a manipulator arm (3) being manually movable relative a two-dimensional coordinate system and carries a manually actuable picking tool (4) for transferring individual components from stores (15-17) to a pre-determined position on a printed circuit board (9). The manipulator arm is actuable by a braking force generated by such as electrical motors for counteracting any further manual movement of the manipulator arm at the pre-determined position.

Description

Manually Operated Surface Component Assembler

DESCRIPTION

Technical Field

The present invention relates to a manually operated surface component assembler including a manipulator arm being manually movable relative to a two-dimensional coordinate system and carrying a manually actuable picking tool for transferring individual components from stores to a predetermined position on a substructure, e.g. a printed circuit board, on which the component is to be assembled. Background Art

Su-ch surface component assemblers are known, and are used for assembling such as electrical circuit components on printed circuit boards. In the apparatus in question there is a manipulator arm with a picking tool, which can be manually moved from a store carrying a supply of circuit components to the position on the circuit board where the circuit component is to be assembled. The picking tool has a pneumatically function¬ ing suction nozzle which picks up the circuit component from the store and places it on the circuit board. The nozzle is rotatable for adjusting the position of the circuit component. The known apparatus has substantially facilitated the work of assembling the often very small circuit components intended here. However, it has still been found troublesome and tiring to get these very small circuit components in the right position on the circuit board, particularly since it is a question of several tens of such circuit components on each circuit board and a relatively long series of circuit boards wh ch are to be assembled but still being unsuitable for automatic component assemblers of robot type due to too short manufacture series to be profitable in use of such complicated assemblers. Disclosure of Invention

For improving the known apparatus and still further facilitating the operator^rs work, the manipulator arm in the surface component assembler in accordance with the invention is actuable by a braking force, which is arranged to counteract any further manual displacement of the manipulator arm past the pre- determined position where the circuit component is to be assembled on the circuit board. In such a way the operator notices that the right position is reached above the circuit board for the actual component.

The means generating the braking force can be a friction lock, or preferably electrical motors which are coupled to the manipulator arm. In the mentioned- pre¬ determined position the voltage supply to the electrical motors gives rise to a force counteracting the manual displacement. Other means are also conceivable, such as voltage-supplied solenoids, stepping motors and the like_ In a semi-automatic embodiment of the inventive surface component assembler a programmable microcomputer is arranged to regulate the position of the pre-determined position relative to the circuit board, so that after assembly of a circuit component an automatic movement to the next following assembly position takes place. The programmable microprocessor can also be utilized for advancing the stores when provided with a plurality of individual cups for different circuit component types and when another circuit component type is to be the sub¬ ject of assembling in- the following assembly position. Preferred Embodiments

The present invention will now be described in more detail in connection with a preferred embodiment, which are depicted on the accompanying drawings, where Figure 1 shows a manually operated surface component assembler device according to the present invention, and

Figure 2 shows a coordinate system to illustrate the function of the assembler device.

As shown in Figure 1 a surface component assembler includes a slide 2 carrying a manipulator arm 3. The manipulator arm 3 is movably mounted in the slide 2 such that it can be moved in a direction A at right angles to the direction B in which the slide 2 can move. There is a picking tool 4 situated at the free end of the manipulator arm 3, the tool including a pneumatic suction nozzle 5, which can be turned by a thumb wheel 6.

The operator 1 operates the assembler device by holding the thumb wheel 6 and manually moving the manipulator arm 3 and slide 2 from a supply 15, 16, 17 of circuit components to the position where the component which has been picked up shall be assembled and vice versa. The supply of circuit components may comprise a carousel plate 16, which has one, two or more rows of cups 8 intended for different component types. The carousel plate 16 is rotatable by a means 11 so that the cup 8 in question can be advanced to a pickding position. Examples of other supplies are shown in form of the component plate 15 having cups 8 and in form of the store 17 for tape stored components.

The slide 2 includes an electrical motor for acting on the manipulator arm 3 and is acted on itself by a second electrical motor 13. The motors are voltage supplied in such a way that when a pre-determined assembly position, determined by a coordinate system, has been arrived at a braking force is generated. Due to the generation of counteracting torque in the electrical motors at the pre-determined position the slide 2 and manipulator arm 3 will be sluggish or have their movement past the assembly position completely inhibited. The assembly position is the point on such as a circuit board 9 where a component is to be assembled.

The counteracting force defining the position is obtained from the electrical motors by feeding them by encoded pulse train signals. By using pairs of such pulse train signals it is also possible to have a direction definition in that the mutually phase positions of the pulse train signals are related to the movement, i.e. if the movement is directed to or from the pre- determined' assembly position.

In Fig. 2 the function of the manually operated surface component assembler device according to the invention is shown by a coordinate system. A component is to be transferred from the cup 8 to the assembly position 9'. The operator 1 after having picked the component up from the cup 8 with the suction nozzle 5 manually displace the manipulator arm 3 (according to Fig. 1) from the cup 8 in the direction of the arrow P. As is made clear in Fig. 2 the assembly position 9' is mainly ^~iπ the origin of the coordinate system. When the manipulator arm 3 is manually moved in the direction of the arrow P it will hit the Y-axis of the coordinate system. At that instance the electrical motor acting on the manipulator arm 3 will generate a braking force as the pulse train signals fed to the motor at that moment are in phase with each other just before hitting the Y- axis but get a changed mutual relation after having passed the Y-axis. The braking force obtained is percepted by the operator as a stop but the Y-axis may be passed if the operator is forcing the manipulator arm 3 further. In the case he has manually forced the manipulator arm 3 some way P¹ on the opposite side of the Y-axis and if then he will leave the manipulator arm free the electric motor counter force will return the manipulator arm 3 automatically to the position P" at the Y-axis. When the operator noticed the braking force obtained when the manipulator arm 3 hit the Y-axis he goes on the manual movement in the down-ward direction in Fig. 2 to the X-axis, i.e. to the origin of the coordinate system. When arriving at the position of the X-axis again a braking force is generated, now by the electrical motor connected to the slide 2. Thus, the operator once more percept the braking force generation as a stopping action. Just as the case was by the Y-axis described above the braking force at the X-axis may be .traversed by the operator forcing the manipulator arm 3 over the X-axis position. If then the manipulator arm 3 is left free it will be returned automatically to the X-axis by the motor counter force. The manual moving action from the cup 8 to the assembly position 9' must not of course follow the arrow P but can follow every direction components which together is ending in the origin of the coordinate system. If the operator 1 try manually to move the manipulator arm 3 along a direction component away from origin, e.g. as shown by the dashed arrow S, immediately a counter force is generated by the electrical motors due to the pairs of pulse train signals fed to them. It is determined that one of the two pulse train signals in a pair has to be leading when the manipulator arm 3 is manually moved in the direction of origin otherwise the counter forces are generated by the electrical motors. One of the signals of the pair of pulse train signals fed to the electrical motor is a reference signal. The other one of the pair of pulse train signals is generated in dependence of the manual movement of the manipulator arm 3. Each one of the two electrical motors detects and is acted on by the mutual relation between the two pulse train signals in such a way that a movement in the direction to the origin does not generate any braking force but a movement directed away from the origin will generate a counter force.

A passing over the X- or Y-axis causes a braking and returning force to be generated by the electrical motors. This will be understood by the operator as if the system has some type of spring action with automatic return to X- and Y-axes respectively when trespassing thereof. In a preferred embodiment of the surface component assembler in accordance with the invention, a substructure which is to be provided with different components is placed in a frame means 10, in this case the substructure is printed circuit boards 9. The frame means 10 defines a coordinate system, the origin of which is the position on the respective circuit boards 9 where the next component is to be assembled.

The frame means 10 can be movable such as to successively take the different assembly positions to the origin. In this embodiment with a movable frame means 10 and with positionable supplies 15, 16, the slide 2 can be dispensed with and the braking force of the manipulator arm 3 can be achieved in its simplest form by a mechanical abutment. A programmable microcomputer 14 may be used for controlling the slide 2 and the braking forces of the manipulator arm 3, i.e. at the point, the assembly position, where the voltage direction of the electrical motors shall be changed. In the case where the frame means 10 Is movable, this movement is regulatable with the aid of the microcomputer 14 for the mentioned successive setting of the assembly positions at the origin of the coordinate system.

The microcomputer 14 can also be connected to the moving means 11 for rotating the carousel plate 16 so that the right cup 8 is put into the picking position for the next assembly operation.

As will be seen from the description given above, a semiautomatic surface component assembler can be achieved by computer controlled regulation of the switching of the braking force of the electrical motors and/or the movement of the frame means 10 to put the assembly positions at the origin. Of course, other variations and modi ications are conceivable within the scope of the invention. For example, the electrical motors can be replaced by solenoids provided with friction braking means. The embodiments described above are therefore not to be regarded as restricting the scope of the invention .

Claims

CLA I MS

1. A manually operated surface component assembler device including a manipulator arm (3) being manually movable relative to a two-dimensional coordinate system and carrying a manually actuable picking tool (4) for transferring individual components from stores (15 - 17) to a predetermined position on a substructure (8), e.g. a printed circuit board, on which the component is to be assembled, characterized in that the manipulator arm (3) is actuable by a braking force arranged to counteract the manually displacement of the manipulator arm past the pre-determined position such that the operator notices that the right position is reached at for the actual component.

2. The assembler device as claimed in claim 1, characterized in that the braking force is generated by a settable friction lock.

3. The assembler device as claimed in claim T, characterized in that the braking force is generated by electromechanical means, e.g. electrical motors being connected to the manipulator arm (3), and by voltage supply at said position generating a force counteracting the manually displacement, said counteracting force being noticed by the operator as the said braking force.

4. The assembler device as claimed in any one of the preceding claims, characterized in that the sub¬ structure (9) is settable against a frame means (10) for determining the pre-determined position, where said frame means is forming the said coordinate system, the origin of which constitutes said position.

5. The assembler device as claimed in any one of the preceding claims, characterized by a programmable microcomputer (14) for displacing said pre-determined position such that it automatically adjusts itself according to the assembly of a component in progress.

6. The assembler device as claimed in claims 3 and 5, characterized in that the microcomputer (14) is adapted for controlling the voltage supply to the electrical motors.

7. The assembler device as claimed in claims 4 and 5, characterized in that the microcomputer (14) is arranged for regulating the displacement of the frame means (10) such that after assembly of a component the substructure is automatically moved to the next successive assembly position.

8. The assembler device as claimed in any one of claims 5 - 7, and where the stores (15 - 17) is formed with a plurality of individual cups (8) intended for different component types, the stores being movable for positioning of the cup containing a component tyjpe about to be assembled, characterized in that the stores (15 - 17) has a displacing means (11) settable by the programmable microcomputer.