GB2096498A - Apparatus for mounting chip type circuit elements - Google Patents

Abstract

A mounting mechanism 16 comprises a rotably indexing disc 40 on which a plurality of mounting heads 15 are radially situated. Each of the mounting heads comprises a suction pin 44 for picking up a chip type circuit element 20 and holding it while the mounting head is indexed to the mounting position E. A shaft 45 of the mounting head is then depressed by a cam follower 80 to press the circuit element 20 on to a portion of a printed circuit board 3 to which adhesive 90 has been applied. The mounting direction can be altered by means of a gear 46. A claw mechanism 120 (shown in Figures 10-13) may be provided for correcting the position of the circuit element 20. <IMAGE>

Description

SPECIFICATION Apparatus for mounting chip type circuit elements This invention relates generally to apparatus for mounting chip type circuit elements on a printed circuit board and, in particular, to a mechanism for mounting chip type circuit elements which do not have lead wires associated therewith on a printed circuit board in a serial or one-by-one fashion.

United Kingdom Published Patent Application No.

2025910 filed by the same applicant as the instant application, discloses apparatus for mounting chip type circuit elements on a printed board.

Our copending Patent Application No. 2076709A described an improved apparatus for mounting chip type circuit elements on printed circuit boards and claims such apparatus comprising: supply unit means for supplying chip type circuit elements; a plurality of pallets and means for conveying said pallets in an intermittent fashion in a particular direction; sequence head means for shifting said chip type circuit elements from said supply unit means onto said pallets; an X-Y table and means for conveying printed circuit boards onto said X-Y table; mounting means including at least one mounting head for mounting said chip type circuit element on a printed circuit board carried by said X-Ytable; and shifting head means for shifting said chip type circuit elements from said pallets to said at least one mounting head, the arrangement being such that in use, when said sequence head means shift said circuit elements onto said pallets from said supply unit means, said pallets are conveyed in an intermittent fashion in said particular direction, said shifting head means shifts said circuit elements to said mounting head from said pallets, and said mounting means mounts said circuit element on a printed circuit board carried by said X-Y table.

The present Application has been divided from our aforesaid British Patent Application No.8116472.

According to the present invention there is provided a mechanism for mounting chip type circuit elements comprising an indexing member, means for rotating said indexing member in an intermittent manner, and a plurality of mounting heads mounted on said indexing member, and wherein each mounting head includes a mounting head shaft mounted for both rotation and for axial sliding movement, actuating means for moving said mounting head shaft in an axial direction, a suction pin mounted on an end of said mounting head shaft and adapted to pick up and hold the chip type circuit element, and gear means for transmitting a rotational torque to said mounting head shaft.

The use of such a mounting head mechanism enables the circuit elements to be mounted in the printed circuit board in a reliable fashion even after the insertion in such board of other electronic components having electrical leads.

Since the general context of the present invention is described in detail in the specification of Application No. 8116472, the following description of an embodiment of the present invention and attendant advantages thereof will be confined to the specifically relevant parts of the present specification and drawings (Figures 8-9 and 19-28) which are reproduced as the accompanying drawings in which ::- Figure 1 is a front elevational view of a mounting mechanism embodying the present invention; Figure 2 is a side view shown partly in section illustrating the mutual positional relationship between the mounting mechanism and the pallets and shifting head of the apparatus described in the present invention; Figure 3 is a plan view shown partly in section of apparatus for adjusting the position of the chip type circuit element on the mounting head of the mounting mechanism; Figure 4 is a front elevational view of the mounting mechanism and associated components in accordance with one embodiment of the present invention; Figure 5 is a plan view of the mounting mechanism illustrated in Figure 4; Figure 6 is a front elevation view in section of a mounting head utilized in this mounting mechanism;; Figure 7 is a side elevational view in section of the mounting head illustrated in Figure 6; Figure 8 is a side elevational view in partial section of apparatus for shifting the chip type circuit element to the mounting head; Figure 9 is a schematic front elevational view of apparatus for positioning the chip type circuit element on the mounting head of the mounting mechanism in accordance with one embodiment of the present invention; Figure 10 is a view in the direction of arrow K of Figure 9 of the chip type circuit element positioning apparatus; Figure 11 is a horizontal sectional view of the apparatus illustrated in Figure 10; Figure 12 is a side elevational view in section of the apparatus illustrated in Figure 9; and Figure 13 is an enlarged view of the claws forming a part of the circuit element positioning apparatus illustrated in Figure 10.

Referring to Figure 1,the mounting mechanism 16 constitutes a rotatably mounted indexing disc 40 on which eight mounting heads 15 are radially arranged at 450 intervals. The indexing disc 40 is fixed to a rotary drive shaft 41 which projects forwardly from the frame 13 as seen in Figures 2 and 3. The drive shaft 41 is itself adapted to be rotatably driven in an intermittent fashion through 45 intervals.

Each of the mounting heads 15 is essentially identical to the others and only one is shown and described for purposes of clarity. A mounting member 42 is fixed to the indexing disc 40 and carries bearings 43A and 43B which themselves support a mounting head shaft 45 which is provided with a suction pin 44 at its end in a manner such that the mounting head shaft 45 is slidable in the radial direction on the indexing disc 40. A gear 46 is keyed to the periphery of the mounting head shaft 45 so as to be rotatable as a unit with the latter. Such mounting is accomplished by a keyway 47 which, although preventing rotation of gear 46 with respect to the shaft 45 does not prevent the gear 46 from moving in the axial direction of the mounting head shaft 45 relative to the latter. A spring attachment block 48 is fitted to the mounting shaft 45 for axial movement as a unit with the latter.Tension springs 50 extend between the spring attachment block 48 and a spring retainer 49 projecting from the indexing disc 40. In this manner, the suction pin 44 is continuously biased in a retracting direction by the springs 50, i.e., in a direction towards the center of the indexing disc 40. The suction pin 44 has a hollow pipe-like construction and is adapted to pick up and hold a chip type circuit element upon the internal cavity of the pin being communicated with a vacuum source.

The mounting heads 15 are adapted to be successively moved in an intermittent fashion from the position A to positions B, C, D, E, F, G and H as shown in Figure 1 in accordance with the rotation of the indexing disc 40.

Each mounting head 15 is adapted to receive a chip type circuit element from the shifting head 18 when the mounting head is directed upwardly, i.e., when in the position A in Figure 1.

Referring to Figure 2 the shifting head 18 is provided with one suction pin 60 which, like the suction pins 21 of the sequence head 10 (see Figures 1-10 of the parent specification) has a hollow pipe-shaped body and is adapted to pick up and hold the chipe type circuit element 20 as a vacuum is applied to the internal cavity thereof. As shown in Figure 2, the shifting head 18 moves downwardly over the pallet 8 to pick up and hold a chip type circuit element 20 whereupon the shifting head 18 moves upwardly and then horizontally to a position above the particular mounting head 15 which is in position A on indexing disc 40 as shown in phantom.

Subsequently, the shifting head 18 is lowered to deliver the circuit element 20 to the suction pin 44 of the mounting head 15. After the circuit element is delivered to the mounting head 15 as described above, the shifting head 18 releases the same and moves upwardly to resume the position above the pallet 8. The chip type circuit element thus delivered is held by the suction pin 44 of the mounting head 15.

Referring to Figure 3, upon the mounting head 15 being rotated to its lateral position, i.e., position C on indexing disc 40, the mounting direction of the chip type circuit element 20 is adjusted. More particularly, an attaching plate 70 is fixed to the frame 13 in a manner so as to extend transversely of the indexing disc 40. A motor mounting plate 71 is vertically attached to the attaching plate 70 so that it is able to slide in a lateral direction as indicated by arrows J. A pulse motor 72 is mounted on motor mounting plate 71 having a gear 73 fixed to its output shaft. A gear 74 is rotatably mounted on mounting plates 71 and meshes with the gear 73 of pulse motor 72.During the intermittent rotation of indexing disc 40, the mounting plate 71 is retracted to the left as seen by the upper arrow J in Figure 3 so as not to hinder the rotation of indexing disc 40 whereby the gear 74 is disengaged from the gear 46 of mounting head 15.

When the rotation of indexing disc 40 is terminated, the gears 74 and 46 are engaged with each other so as to adjust the mounting direction of the chip type circuit element 20. In the illustrated embodiment, the mounting head shaft 45 of mounting head 15 is rotated 150 for each operation step of the pulse motor 72.

Referring backto Figure 1 upon the mounting head 15 reaching position E, i.e., its downwardly directed position, a cam follower 80 mounted for vertical movement on attaching plate 70, as shown in Figure 3, depresses the head of the mounting head shaft 45 whereby the chip type circuit element 20 held on the suction pin 44 contacts the printed circuit board 3 and is attached thereto by adhesive as described in the parent specification.

The operation of the chip type circuit element mounting apparatus of the present invention will now be described. At the initial stage of operation, the X-Ytable 2 (shown in Figures 5,4, 6,7 and 9) assumes an origin position and in this condition the supply of the printed circuit board is commenced to the right position R of the X-Y table 2.

At this point, adhesive is applied according to a predetermined program to the locations on the printed circuit board 3 to which the circuit elements are to be mounted by means of the dispenser 14. The X-Ytable 2 is then returned to its origin position after the completion of the adhesive application. During this procedure, the sequence head 10, shifting head 18, and mounting head 15 remain idle.

While the X-Y table is stationary at its point of origin after the application of adhesive to the printed circuit board 3 a plurality of chip type circuit elements 20 are mounted on a pallet 8 by means of the sequence head 10 according to a predetermined program as described above.

Thereafter, the pallets 8 are moved to the left in an intermittent fashion by the pal lets transfer 9 so that the circuit elements 20 on the pallets 8 are successively shifted to the mounting heads 15 through the operation of the shifting head. The operation is momentarily stopped as the mounting head 15 carrying the first circuit element reaches the mounting position E as shown in Figure 1.

During the momentary stoppage of operation, the printed circuit board 3 which has reached the right-side position on the X-Y table 2 is then moved to a central position CT and a new printed circuit board is supplied to the right side position R by the loader 4 (see Figure 1 of the parent specification).

Thereafter, the mounting of the chip type circuit element 20 to the printed circuit board 3 which is in the central position CT and the application of the adhesive to the printed circuit board 3 on the right side position R are simultaneously commenced.

The mounting head shaft 45 of the mounting head 15 upon reaching the position E of Figure 1 is depressed by the cam follower 80 so that the suction pin 44 is lowered to press the chip type circuit element 20 held by the suction pin 44 onto the portion of the printed circuit board 3 where adhesive has been applied whereupon the circuit element is mounted on the printed circuit board 3. The applica tion of the vacuum to the suction pin 44 is stopped only when the mounting head shaft 45 has been lowered so that the mounting operation of the circuit element onto the printed circuit board can be reliably accomplished.

After the operations described above have been completed, the X-Y table 2 is returned to its original position so that the printed circuit board 3 on which the chip type circuit element has been mounted is - moved from the central position CTto the left position L while at this time the subsequent printed circuit board is moved from the right side position R to the central position CT. During this time, a new printed circuit board is fed to the right side position R.

Thus, the application of adhesive to the printed circuit board and the mounting of the chip type circuit element thereto are accomplished at the right side R and central CT positions, respectively. Simultaneously, checker 17 operates to monitor and detect any misrnounting of the circuit element on the printed circuit board at the left side position L. If no mismounting is detected, the printed circuit board is removed from the X-Y table 2 by means of the unloader 5 (see Figure 1 of the parent specification).

In accordance with the embodiment of the invention described above, it is possible to mount the chip type circuit elements even after the printed circuit board has been loaded with other electronic components since the mounting of the circuit elements 20 on the printed circuit board 3 is achieved by means of the mounting head 15 having suction pins 44.

Additionally, by virtue of the operation of the sequence head 10, it is possible to arrange different kinds of chip type circuit elements 20 on the train of pallets 8 in an appropriate sequence so that it is possible to mount a plurality of different kinds of chip type circuit elements on the printed circuit board.

It should be noted that the gear 46 of the mounting head 15 of mounting mechanism 16 is locked in a particular position by a lock mechanism unless it is necessary to alter the mounting direction of the chip type circuit element.

Thus, apparatus for mounting chip type circuit elements on printed circuit boards are provided wherein the circuit elements can be mounted on even small vacant spaces provided on the printed circuit board.

The mounting mechanism 16 which mounts the chip type circuit elements 20 on printed circuit boards 3 will now be described in greater detail with reference to Figures 4-8. It is noted that such mounting mechanism is specially suited for mounting chip type circuit elements having no lead wires in a one-by-one fashion on a printed circuit board.

Referring to Figures 4 and 5 which illustrate the mounting mechanism 16 in its entirety, a rotary drive shaft 41 projects forwardly from the frame 13 and an indexing disc 40 is fixed to the rotary drive shaft 41.

Eight mounting heads 15 are mounted on the front surface of indexing disc 40 so as to extend radially thereon, each mounting head being spaced from the next at a 450 interval. The mounting heads 15 are moved through points A, B, C, E, F, G and H as the indexing disc 40 intermittently rotates at 450 increments in accordance with the intermittent rotation of the rotary drive shaft 41.

Referring to Figures 6 and 7 which illustrate the detailed construction of a mounting head 15, bearings 43A and 43B are fixed to the mounting member 42 which in turn is fixed to the indexing disc 40. A mounting head shaft 45 is rotatably and slidably supported in the radial direction of the indexing disc 40 by bearings 43A and 43B. The end portion of the mounting head shaft 45 has a hollow pipe-like cavity formed therein, the end portion of which constitutes a suction chamber 82 which communicates with the atmosphere through a suction bore 83 which is radially formed in the end of the mounting head shaft. An end piece 84 is threaded to the end of the mounting head shaft. A suction pin 44 is provided which extends through the end piece 84, the suction pin 44 being provided with a central axial suction bore 85.A compression spring 86 biases the suction pin 44 so that the latter projects outwardly from the end piece 84. Further, an annular block 48 for securing the spring is fitted around the mounting head shaft 45. Both sides of the annular block 48 are sealed by means of O-rings 87 and 88 which are secured to the mounting head shaft 45. In this manner, the annular spring attaching block 48 moves as a unit together with the mounting head shaft 45 in the axial direction. A radial suction bore 94 is formed in the spring attaching annular block 48.

A suction plug 95 having a suction bore 96 which communicates with the suction bore 94 is threaded into the spring attaching annular block 48. The suction plug 95 is connected to a vacuum source such as a vacuum pump through a suction hose.

Thus, the vacuum is applied to the suction bore 85 of the suction pin 44 through the suction chamber 82, suction bores 83, 94 and 96 and the suction hose so as to exert a suction force to pick up and hold a chip type electronic component 20. A spring 50 which is stretched between a spring retainer 49 which projects from the indexing disc 40 and the spring attaching annular block 48 acts to bias the mounting head shaft 45 towards a retracting position. Further, a gear 46 is fitted around the mounting head shaft 45 by means of a keyway 47. Thus, the gear 46 is prevented from rotating relative to the mounting head shaft 45 but may slide in the axial direction thereover.

A lock lever 97 is pivotally attached to the rear side of indexing disc 40 through a bracket 98. The front end of the lock lever 97 engages the gear 46 provided on the mounting head 15. Aspring 99 is stretched between the rear end of the lock lever 97 and a spring retainer pin 100 fixed to the indexing disc 40. Consequently, the lock lever 97 is biased to normally lock the gear 46. An elongate lever 101 pivotally secured to the bracket 98 is operatively connected to the lock lever 97. The arrangement is such that the gear 46 will be unlocked as the roller 102 provided at the end of the elongated lever 101 is pushed upwardly.

As noted above, the mounting heads are moved past the points A, B, C, D, E, F, G and H as the indexing disc 40 is rotated as seen in Figure 4. The chip type circuit element 20 is received on the mounting head 15 when the latter is directed upwardly, i.e., when it is in the position designated A as seen in Figure 8.

Referring to Figure 8 the chip type circuit elements 20 are carried by pallets 8 which are adapted to be moved intermittently by a pallet transfer mechanism 9. A shifting head 18 is provided for shifting the chip type circuit element 20 from the pallet 8 to the suction pin 44 of the mounting head 15. The shifting head 18 is adapted to be lowered from a position above the pallet 8 to pick up the chip type circuit element 20 on the pallet 8 whereupon it is moved upwardly and horizontally to a position above the mounting head 15 situated in position A, to thereby deliver the circuit element 20 onto the suction pin 44 of suction head 15. Subsequent to such delivery, the shifting head 18 releases the circuit element and is moved upwardly to resume the position above the pallets.The chip type circuit element thus delivered to the suction pin 44 of the suction head 15 is picked up and held by the latter.

Referring now to Figures 4 and 5, a supporting plate 70 is secured to the front surface of the frame 13 through an attachment piece 103 in a manner such that it extends across a space in front of the indexing disc40. A pair of supporting shafts 104 are horizontally mounted on the front surface of the supporting plate 70. A motor mounting plate 71 is fixed to a ball bush 105 which is slidable along the support shafts 104. A pulse motor 72 is mounted on the motor mounting plate 71 and has a gear 73 mounted on its output shaft which meshes with the gear 74 which itself is rotatably secured to the motor mounting plate 71. The motor mounting plate 71 is connected through a connecting rod 106 to one end of a bell crank 107 fixed to an operation shaft 108.An operation block 80 is mounted for sliding movement in the vertical direction at the central portion of the supporting plate 70. The operation block 80 has a roller 109 which is adapted to contact the head 45A of the mounting head shaft 45 and is connected to the other end of the bell crank 107 through a link 110.

When the mounting head 15 assumes a lateral position, i.e., the position C, the mounting direction of the chip type circuit element 20 is switched utilizing the pulse motor 72. In this case, during the rotation of the indexing disc 40, the motor mounting plate 71 is moved in the direction of arrow J to remove gear 74 from engagement with the gear 46 of mounting head 15. When the bell crank 107 is rotated to the left with the indexing disc 40 station ary, the roller 102 is pushed upwardly by the mechanism operatively connected to the bell crank 107 whereby the lock lever 97 is disengaged from the gear 46. During this operation, the gears 46 and 74 are brought into engagement with each other so that the torque of the pulse motor 72 is transmitted to the mounting head shaft 45.In this case, the mounting head shaft 45 undergoes a 15 rotation with each operation of the pulse motor 72 so that the chip type circuit element 20 is set at a desired mounting direction with respect to the printed circuit board 3.

Simultaneously with the switching of the mounting direction of the chip type circuit element at the point C, the mounting head 15 moves to position E where it operates to mount the circuit element 20 on the printed circuit board 3 which is carried by the X-Y table 2. More particularly, as the bell crank 107 rotates in a counter-clockwise direction, the operation block 80 is depressed through the link 110 so that the head 45A of the mounting head shaft 45 is depressed as shown by arrow K.

Consequently, the suction pin 44 at the end of the mounting head shaft is lowered while holding the chip type circuit element 20. At its lowest position, i.e., at the position where the chip type circuit element 20 is pressed on to the printed circuit board 3, the application of vacuum to the suction bore 85 is terminated to thereby release the chip type circuit element. It is possible to mount the chip type circuit element 20 in a fixed position on the printed circuit board 3 through the prior application of an adhesive to the mounting positions on the printed circuit board 3 by dispenser 14 (Figure 9 of the parent specification).

The mounting mechanism for the chip type circuit elements described above operates as follows.

When the indexing disc 40 is stationary, a chip type circuit element 20 is delivered by the shifting head 18 to the mounting head 15 while in the position A. The circuit element is picked up and held by the suction pin 44 of the mounting head 15 and is moved to the position B and then position C in accordance with the intermittent rotation of the indexing disc 40. At the position C, the mounting head 15 is driven by the pulse motor 72 for setting the proper mounting direction of the chip type circuit element.

Thereafter, the chip type circuit element is moved to the position E through the position D where the head 45A of the mounting head shaft 45 is depressed by the roller 109 of the operation block 80 to thereby mount the chip type circuit element 20 on the printed circuit board 3 carried on the X-Y table 2. The mounting head 15 which has passed through the position F in a vacant condition is then returned to the position A past the positions F, G and H to receive a new chip type circuit element 20.

From the foregoing, it is seen that the mounting mechanism described above offers the following significant advantages.

Firstly, since the mounting of the chip type circuit element 20 is accomplished by a mounting head having an elongated suction pin 44, it is possible to mount the chip type circuit element even in a limited space on the printed circuit board 3 as in the case where such circuit elements are mounted subsequent to the insertion of other electronic elements in the printed circuit board 3.

Secondly, since the suction pin 44 is biased by compression spring 86, a suitable cushioning effect is provided to insure the safe mounting of the circuit element on the printed circuit board 3 while avoiding the possibility of any damage thereto.

Thirdly, since a plurality of mounting heads 15 are arranged on the indexing disc 40 to successively perform the picking up, mounting direction setting, and mounting of the chip type circuit elements on the printed circuit board, it is possible to obtain relatively high operational speeds.

Accordingly, the present invention provides apparatus whereby a chip type circuit element can be mounted within a small space on a printed circuit board in a reliable and fast manner.

It is often desirable to adjust the chip type circuit elements into a correct position as the same are conveyed to the printed circuit board. In this embodiment of the present invention the circuit elements# are so conveyed by picking up the circuit elements on mounting heads 15 of a mounting mechanism 16 and it is often necessary in this connection to eliminate any deviations of the chip type circuit elements from the desired position and to properly position the chip type circuit element in a desired orientation.

Referring to Figures 9-13, apparatus for accomplishing such positioning of a chip type circuit element is disclosed.

As seen in Figure 9 and as described in greater detail hereinabove, an indexing disc 40 carries eight mounting heads 15 which are radially arranged on the disc and spaced from each other at 45 intervals.

As the rotary drive shafts 41 intermittently rotates through 45 steps, each mounting head 15 is successively moved from a vertical position A through the positions B, C, D, E, F, G and H. When located at the position A, the chip type circuit element 20 is transferred from a pallet which itself has been conveyed by a pallet transfer 9 to the mounting head 15 which is adapted to pick up and hold the chip type circuit element under suction forces. A supporting or attaching plate 70 is situated in front of the indexing disc 40 and has a supporting arm fixed thereto which supports a mechanism, generally designated 120, for positioning the chip type circuit element 20 after the same has been brought to the position B by the indexing disc 40.As described above, the circuit element 20 is mounted on the printed circuit board 3 which is carried on X-Y table 2 by mounting head 15 which has rotated to the position E.

Figures 10-12 illustrate in detail the mechanism 120 for positioning the chip type circuit elements. A rack holding block 121 is mounted on a supporting arm 122 which itself is fixed to supporting plate 70 extending upwardly therefrom. A pair of parallel racks 123A and 123B are slidably mounted on the rack holding block 121. A pair of claws 124A and 124B are fixed to the ends of the racks 123A and 123B, respectively, through respective spacers 125A and 1258. A pinion 126 is mounted on the central portion of the rack holding block 121 and meshes with the pair of racks 123A and 123B to drive the same in opposite directions. An operation arm 127 is fixed to pinion 126. A cylinder 129 is fixed to a cylinder supporting arm 128 which extends from the rack holding block 121, a piston rod 130 being reciprocally mounted in cylinder 129.The piston rod 130 extends in a direction such that its end 131 contacts the operation arm 127. A spring 132 is stretched between the operation arm 127 and the supporting arm 128 so as to continuously urge the pinion 126 in the clockwise direction as best seen in Figure 10.

Figure 13 illustrates the claws 124A and 124B on an enlarged scale. The claws 124A and 124B are formed with respective notches 133A and 133B having orthogonal apex angles. The notches are formed such that as the claws 124A and 124B move with the respective racks 123A and 123B, the apex portions 134A and 134B are always opposed to each other along the diagonal line J which passes through opposed corners of the chip type circuit element when the latter is positioned at its correct location.

The claws 124A and 124B are kept open, i.e., spaced from each other, during the rotation of the indexing disc 40 so as not to hinder the transfer of the chip type circuit element 20. This is accomplished by actuating the cylinder 129 so that the pinion 126 is in its extreme counter-clockwise position. When the rotation of the indexing disc 40 is terminated, i.e., between the intermittent advancements thereof, and a chip is held on a mounting head 15 in the position B (Figure 9), the cylinder 129 is deactivated so that the pinion 126 rotates in a clockwise direction under the force of spring 132. As a result, the claws 124A and 124B are moved in opposite directions designated by arrows M and N until they abut the opposed corner or apex portions of the chip type circuit element 20 thereby setting the circuit element in its correct position.In other words, the apex portions 134A and 134B of notches 133A and 1338 which are formed in claws 124Aand 124B coincide with the corresponding corners of the chip type circuit element 20. Consequently, the circuit element is set at its correct position even when it is initially picked up by the mounting head in a position which deviates from its correct position.

After the chip type circuit element is positioned as described above, the claws 124A and 124B are again opened so that the correctly positioned circuit element 20 is then conveyed through the rotation of the indexing disc 40 through the positions C, D, and E whereupon it is finally mounted at the position E on the printed circuit board 3.

The mechanism for positioning chip type circuit elements described above offers several important advantages.

Firstly, since the claws 124A and 1 24B are moved in the direction of the diagonal line J which passes through opposed corners of the circuit element, the latter will be properly located in both the lateral and vertical directions to thereby eliminate any undesirable deviations in position of the circuit elements 20 from the desired position and, additional!y, any deviations in the inclination of the chip type circuit element will also be corrected.

Secondly, the positioning mechanism can be utilized to position circuit elements 20 having varying shapes and sizes as indicated by circuit elements 20A and 20B which have somewhat similar configurations as seen in Figure 13.

Thirdly, the clamping of the chip type circuit elements 20 by the claws 124A and 124B is accomplished utilizing the resilient force exerted by the spring 132 while resetting of the claws 124A and 124B is effected by the cylinder 129. In this manner, no excessive forces are applied to the chip type circuit element which might damage the same.

Although the embodiment of the positioning mechanism for chip type circuit elements has been described above in connection with positioning the circuit elements as the same are held on a mounting head 15, it will be understood that the mechanism is also useful in connection with positioning chip type circuit elements on a pallet as well as to positioning such circuit element during other steps of the operation of the apparatus. In summary, a mechanism for correctly positioning a chip type circuit element is provided wherein the circuit element can be set in both its correct lateral and vertical directions, as well as in its correct inclination, in a reliable manner.

Obviously, numerous modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the claims appended hereto, the invention may be practised otherwise than as specifically disclosed herein.

Claims (6)

1. A mechanism for mounting chip type circuit elements comprising an indexing member, means for rotating said indexing member in an intermittent manner, and a plurality of mounting heads mounted on said indexing member, and wherein each mounting head includes a mounting head shaft mounted for both rotation and for axial sliding movement, actuating means for moving said mounting head shaft in an axial direction, a suction pin mounted on an end of said mounting head shaft and adapted to pick up and hold the chip type circuit element, and gear means for transmitting a rotational torque to said mounting head shaft.

2. A mechanism as claimed in Claim 1 in combination with apparatus for positioning a chip type circuit element comprising a first claw having a first notch formed therein defining a substantially orthogonal apex portion, and a second claw having a second notch formed therein defining a substantially orthogonal apex portion, said first and second claws being movably mounted such that said apex portions of said first and second claws are in mutually opposed relationship and situated along a line passing through diagonal corners of a chip type circuit element which is positioned at a desired position.

3. A mechanism as claimed in Claim 1, wherein said apparatus is substantially as hereinbefore described with reference to Figures 9-13 of the accompanying drawings.

4. A mechanism as claimed in Claim 1,2 or 3 wherein the mounting head is substantially as hereinbefore described with reference to Figures 1-8 of the accompanying drawings.

5. A mechanism for mounting chip typ circuit elements, substantially as hereinbefore described with reference to Figures 1-8 of the accompanying drawings.

6. A mechanism as claimed in Claim 5 in combination with apparatus for positioning a chip type circuit element according to Claim 3.

Apparatus for mounting chip type circuit elements upon printed circuit boards, which apparatus includes a mechanism according to any one of the preceding claims.