WO2009129934A2

WO2009129934A2 - Plunger with centering back into the inserted position

Info

Publication number: WO2009129934A2
Application number: PCT/EP2009/002657
Authority: WO
Inventors: Simon Murnauer; Johann PÖTZINGER; Franz Pichl; Andreas WIESBÖCK
Original assignee: Multitest Elektronische Systeme Gmbh
Priority date: 2008-04-24
Filing date: 2009-04-09
Publication date: 2009-10-29
Also published as: DE102008020558A1; WO2009129934A3; DE102008020558B4

Abstract

The invention relates to a plunger comprising a support part (2) and a slide part (3) that slides in a displaceable manner on the support part (2). Said support part (2) also comprises centering means protruding in the direction of the head (23) of the plunger, said centering means being in central contact with head of the plunger (23) when the slide part (3) is in the inserted position and not in central contact with the plunger head (23) when the slide part (3) is in the open position.

Description

Plunger with recentering

The invention relates to a plunger for feeding and moving away an electronic component, in particular an IC, to or from a contacting device connected to a test device, having a plunger holding part and a plunger sliding part, according to the preamble of claim 1.

Electronic components, such as ICs

(Semiconductor devices with integrated circuits), are usually tested for their functionality before they are mounted, for example on printed circuit boards or otherwise used. In this case, the components to be tested are contacted by a handling machine conventionally designated as a "handler" with contacting devices, which are formed in particular from contact bases and are in electrical contact with a test head of a test device. After completion of the test process, the components are removed by means of the handler again from the contacting and sorted depending on the test result.

Handlers commonly have plungers for holding and contacting the components, ie, holding units comprising a plunger-holding member attached to a pivoting device or a circulation carriage of the handler and a plunger sliding member having a plunger head longitudinally displaceably guided on the plunger-holding member, which comprises a component to be tested, particularly by applying a suction force Can keep negative pressure (vacuum). The plungers are, after the components have been placed, for example by means of a pick and place unit on the plunger head, placed within the handler in a position in which the Plungerschiebeteil with the plunger head on straight forward path can be advanced to the contacting until the components come into contact with the contacting. After carrying out the test operations, the components are removed again from the test head by means of the plungers and positioned so that they can be removed from the handler via an unloading station and sorted as a function of the test result.

It is necessary that the plunger head with advanced Plungerschiebeteil exactly centered relative to the contacting (contact socket with contact springs or contact pins) to ensure that the terminals of the device under test are placed exactly on the associated contact springs or contact pins of the contacting. To achieve this, as is known, centering means are provided in the area of the contacting devices with which the plunger head engages shortly before the contacting operation. However, this can lead to side forces being generated by the centering means of the contacting devices, which lead to tension in the plunger. Furthermore, it is possible for the contacting plane of the plunger head at the time of contacting not to be arranged exactly plane-parallel to the contacting plane of the contacting devices, so that not all connection contacts of a component to be tested or several components to be tested simultaneously are contacted with the same pressure force.

The invention has for its object to provide a plunger of the type mentioned, which allows accurate positioning of the plunger head in the advanced position of Plungerschiebeteils without tensions occur in the plunger. Furthermore, the plunger head in the retracted position of the Plunger sliding parts are kept stable laterally.

This object is achieved by a plunger with the features of claim 1. Advantageous embodiments of the invention are described in the further claims.

In the plunger according to the invention, the plunger head is movably supported on the base body. Furthermore, the plunger holding part has a centering means projecting in the direction of the plunger head, which is in centering engagement in the retracted position of the plunger sliding part and out of centering engagement with the plunger head in the advanced position of the plunger sliding part.

The movable mounting of the plunger head on the base body of Plungerschiebeteils allows centering of the plunger head and thus held on the plunger head semiconductor device when the plunger head engages with the centering of the contacting, wherein the plunger head relative to the base body can be moved laterally and / or tilted. This centering just before the contacting process can thus be done without obstruction and in a very smooth manner, with tension in the plunger are avoided. Further, the invention thus provides a "recentering", ie centering which becomes effective upon retraction of the plunger head to its retracted position so that the plunger head is centered in this retracted position relative to the plunger support member and in a well-defined position , This recentering serves to return the plunger head in the retracted position of the plunger in a central basic position, after he may possibly in the extended state, ie at a previous centering operation when contacting a contact socket or other contacting, has been moved relatively far laterally relative to the Plungerkopf- basic body. Such a lateral displacement of the plunger head could in fact lead, without centering, to the fact that the centering means located there are no longer properly hit during the next centering operation in the area of the contacting devices. On the other hand, the back centering causes the plunger head to be returned to a defined starting position after each contacting operation. The back centering further causes the plunger head in the retracted position of the plunger on

Plunger head base body is fixed so that it is fixed in this state shift. This ensures that the plunger head can not move unintentionally when the plunger is moved in its retracted position within the handler, in particular also greatly accelerated and decelerated. If the Plungerschiebeteil, however, advanced, the sliding latch of the plunger head is released, so that the plunger head can "float" again to allow a tension-free centering with the contacting.

According to an advantageous embodiment, the centering means of the Plungerhalteteils consists of at least one centering pin which is attached to the Plungerhalteteil and protrudes in the direction of the plunger head. Furthermore, the plunger head per centering a center hole, in which the centering pin when moving back

Plunger push part is inserted into its retracted position.

According to an advantageous embodiment, the base body has a base part and a coupling plate, which is mounted transversely to the axial direction of the plunger floating on the base part, wherein the plunger head is supported on the coupling plate and the coupling plate per centering pin has a bore through which the centering pin can be passed with lateral play. The lateral clearance between the centering pin and the bore of the coupling plate allows the coupling plate to move and align laterally with the plunger head when the centering pin or pins are inserted through the coupling plate into the center hole (s) of the plunger head. ,

According to an advantageous embodiment, two centering pins are provided, wherein the base part of Plungerschiebeteils has guides in which the centering pins are guided longitudinally displaceable. This allows the Plungerschiebeteil be performed symmetrically and very precisely.

According to an advantageous embodiment, the Plungerschiebeteil a designed as a guide element, tubular vacuum supply line which penetrates the Plungerhalteteil and is guided in this longitudinally displaceable. In this case, an additional guide means for the Plungerschiebeteil is provided by the vacuum supply line. The vacuum supply line is expediently located centrally between the centering pins, wherein it is aligned with the central longitudinal axis of the plunger. Appropriately, in this case serves the tubular vacuum supply line simultaneously from plunger part, with which the Plungerschiebeteil is advanced.

Conveniently, the plunger head is not only laterally displaceable, but also rotatably and / or tiltably supported on the coupling plate. This allows the plunger head and thus the test to be tested Device by means of the centering device, which is provided in the region of the contacting, align in a particularly accurate and disability-free manner such that the terminal contacts of the device can be placed exactly on the associated contact springs or contact pins of the contacting.

The invention will be explained in more detail by way of example with reference to the drawings. Show it:

Figure 1: a perspective view of the invention

Plungers with retracted plunger slide,

Figure 2: the plunger of Figure 1 with advanced

Plungerschiebeteil,

3 shows an illustration according to FIG. 1, wherein the plunger is shown cut in the area of the plunger head and the coupling plate, FIG.

FIG. 4 is a view according to FIG. 2, the plunger being cut in the region of the plunger head and of the coupling plate;

Figure 5: a perspective view of the plunger head and the first, spherical locking means in one

Position in which the plunger head is axially displaceable relative to the first locking means,

FIG. 6 shows an illustration of the plunger head and of the first locking means in a position in which the Plunger head is axially locked relative to the first locking means,

7 shows a sectional view through the plunger head and the first locking means of FIG. 6, and FIG

Figure 8 is a plan view of the plunger without plunger head, i. on the

Coupling plate.

The plunger 1 illustrated in FIGS. 1 to 4 essentially comprises a plunger holding part 2 and a plunger pushing part 3, which is held longitudinally displaceable on the plunger holding part 2.

By means of the Plungerhalteteils 2, the plunger 1 may be mounted within a handler on a pivoting device, not shown, or on a Urnlaufwagen. An unillustrated electronic

Component which is placed on a front bearing surface 4 of Plungerschiebeteils 3 and held there by means of vacuum (vacuum) can thus be brought into a position in which the Plungerschiebeteil 3 can be fed straight into a contact position in the terminal pins or terminals of the device be placed on corresponding, not shown terminal contacts of a contact socket. The forward movement takes place by means of a feed device, not shown, which presses on a rear end face 5 of the Plungerschiebeteils 3 and this pushes relative to the Plungerhalteteil 2 forward, as shown in Figure 2 and 4. The return of the plunger 1 in its starting position shown in Figures 1 and 3 via a return spring 6 in the form of a tension spring which is fixed with its rear end to the Plungerhalteteil 2 and with its front end to a base body 7 of the Plungerschiebeteils 3. The Plungerhalteteil 2 has a holding plate 8, a holding body 9 and two centering pins 10. The holding plate 8 is laterally in front of the flange over the holding body 9 and has in two diagonally opposite corner areas holes 11 for receiving screws not shown, with which the holding plate 8 can be screwed to the pivoting device, not shown, or a circulation car.

The holding body 9 is arranged on the rear side of the holding plate 8 and formed integrally therewith. The two centering pins 10 are arranged parallel to one another and fastened at their rear end in the region of the rear end wall of the holding body 9. Furthermore, the centering pins 10 protrude considerably beyond the retaining plate 8. The length of the centering pins is so great that they extend in the retracted state of Plungerschiebeteils 3, as shown in Figure 3, through the entire base body 7 through into center holes 12 of a detachably attached to the base body 7 plunger head 23 inside. In the advanced state of Plungerschiebeteils 3, which is shown in Figures 3 and 4, the centering pins 10 are disengaged from the center holes 12 so that the plunger head 13 rotate relative to the base body 7 and slightly tilt in all directions, as later will be described in more detail. However, in this advanced state of the Plungerschiebeteils 3, the centering pins 10 are still in engagement with

Guide sleeves 14 which are arranged at the rear end of the base body 7. In the retracted state of Plungerschiebeteils 3, the guide sleeves 14 are within the Plungerhalteteils 2, so that they are not visible in Figures 1 and 3. The base body 7 consists of a rear base part 15, at the rear end of the guide sleeves are formed, and a front intermediate or coupling plate 16 which is laterally floating on the base part 15 is supported.

Due to this floating support, the coupling plate 16 can be moved relative to the base part 15 in a plane perpendicular to the longitudinal direction of the plunger 1 to a certain extent. This is achieved in that, as shown in FIG. 8, bores 17 of the coupling plate 16, through which the centering pins 10 protrude in the retracted state of the plunger sliding part 3, have a diameter that is larger by a certain amount than the outer diameter of the centering pins 10. The centering pins 10 thus have within the holes 17 lateral play.

The axial fixing of the coupling plate 16 on the base part 15 by means of two screws 18, of which only the screw heads 19 are visible in Figure 8. The screw shafts of the screws 18 penetrate holes of the coupling plate 16, which in turn have a larger diameter than the outer diameter of the screw shafts. Furthermore, the screw heads 19 are in counterbores 20 whose diameter is greater than the outer diameter of the screw heads 19. The screw heads 19, which engage over the coupling plate 16 in the region of the counterbores 20, hold the coupling plate 16 with little axial play, but laterally movable, on the coupling plate 16.

The coupling plate 16 furthermore has, as can be seen from FIG. 8, an axial bore 21 in order to pass tempered fluid, in particular a tempered gas, through the coupling plate 16 can. Such tempered fluid is used for cooling or heating of the components sucked on the plunger 1, if the components are to be tested under certain temperature conditions. The axial bore 21 is aligned with a further, not shown, axial bore of the base part 15, which communicates with a fluid supply line 22 (Figures 1 to 4) of the Plungerschiebeteils 3 in connection. The fluid supply line 22 penetrates a corresponding recess in the Plungerhalteteil 2 and extends in the retracted position of the Plungerschiebeteils 3 backwards beyond the Plungerhalteteil.

The plunger 1 further has a plunger head 23 which can be fastened on the coupling plate 16 by means of a special quick-locking system which will be described in more detail later. The plunger head 23 essentially has a base 24, a headpiece 25 and a tempering body 26. The head central part 25 is fixedly connected to the base 24 or formed integrally therewith.

The base 24 consists of a rear, cuboidal base portion 24a and a front base portion 24b with reduced outer diameter. A central, axially continuous recess 27 in the base 24 is dimensioned such that in the rear end region of the base 24, the head central part 25 and a sleeve-shaped shaft portion 28 of the tempering 26 can be used from the front.

In the rear base portion 24 a, the two center holes 12 are provided in the form of blind holes, which are aligned in the fully assembled state of the plunger head 23 with the holes 17 of the coupling plate 16. The rear portion 12 a of the center holes 12 widens toward the rear cone-shaped to form an insertion bevel for the centering pins 10. The diameter of the front portion 12b of the centering holes 12, however, is dimensioned so that the centering pins 10 can be received with little radial play when the Plungerschiebeteil 3 is moved back to the outermost retracted end position. In the retracted end position of the plunger head 23 is thus centered by the centering pins 10 relative to the base body 7 and thus also relative to Plungerhalteteil 2. Due to this "back centering", the plunger head 23 is returned to a defined starting position and at the same time locked laterally, so that the plunger head can no longer move laterally in an undesired manner when the plunger is moved rapidly in its retracted position within the handler. If, in contrast, the Plungerschiebeteil 3 moves together with the sucked component forward in the direction of Kontaktsockeis reach the centering pins 10 out of engagement with the centering holes 29 so that the plunger head 23 are moved together with the coupling plate 16 laterally to some extent and also relative to the coupling plate 16 can tilt something in all directions, as will be described later. The cancellation of the rigid coupling between the plunger head 23 and the

Base body 7 makes it possible for the plunger head 23, shortly before it reaches the contacting device arranged on the side of the test device, eg a contact socket, to be centered without tension by other centering means which are arranged in the region of this contacting device. For this purpose, the rear base portion 24a in the corner regions on centering recesses 30, which engage with the not shown, arranged in the region of the contacting centering pins when the device is placed on the contacting. To fix the plunger head 23 to the coupling plate 16, a first locking means 31 in the form of a ball member 32 is attached to the coupling plate 16 which cooperates with a second locking means in the form of four clip members 34 disposed on the head central member 25.

The ball member 32 is mounted centrally on the coupling plate 16 and has a screwed into a central threaded bore of the coupling plate 16 shank portion 35 and a forward projecting beyond the coupling plate 16 spherical head 36. The ball member 32 is provided with a central, continuous vacuum line 37, which communicates at its rear end with a negative pressure supply line 38 of the Plungerschiebeteils 3 (Figure 3) designed as a vacuum tube. The vacuum tube 38 is fixed to the base body 7 and extends between the centering pins 10 and in parallel therewith through the plunger holding part 2 rearwardly to a plunger supply part 39. This plunger supply part 39 has a connection not shown in detail for connecting the vacuum tube 38 to a negative pressure generating means , Furthermore, the fluid supply line 22 also ends in the plunger supply part 39, so that fluid can be introduced into the fluid supply line 22 via the plunger supply part 39. If the fluid is to be heated, a heating device, for example in the form of an electrical resistance heater, which is spirally wound, can also be located in the fluid supply line 22.

The vacuum tube 38, which is guided in a guide bore of the holding plate 8, is used in addition to the two centering pins 10 as a further guide element for guiding the Plungerschiebeteils 3 on Plungerhalteteil second The shank portion 35 of the ball member 32 is also movably connected to the vacuum tube 38 so that the ball member 32 together with the coupling plate 16 can move laterally relative to the base member 15.

On the ball head 36, a spherical cap 40 can be placed, which is part of the head central part 25. Figure 7 shows a state in which the spherical cap 40 rests on the ball head 36. As can be seen from FIGS. 5 to 7, the clip elements 34 consist of finger-like ones

Projections which protrude to the rear over the spherical cap 40, wherein the inner surfaces of the clamping elements 34, as can be seen from the sectional view of Figure 7, the curvature of the spherical cap

40 continue to their free end continuously. The clamping elements 34 extend so far around the Kugeikopf 36 around that the clear distance between two opposing clamping elements 34 in the region of their free ends is less than in their transition areas to the spherical cap 40. In this way, in the position shown in Figures 6 and 7, the plunger head 23 is no longer lifted axially from the ball head 36. On the other hand, a ball head holder is thereby created, which basically makes it possible to pivot the plunger head 23 in all directions or to tilt and to rotate about the longitudinal axis of the plunger 1.

Thus, the plunger head 23 in the illustrated in Figures 6 and 7

Locking position can be brought, the ball head 36 four regularly distributed over its circumference axial grooves or flats

41, which can be seen in particular from Figures 5 and 6. The distance between two opposite axial grooves 41 is slightly smaller than the smallest distance between two In this way, it is possible that the clamping elements 34 are displaced along the axial grooves 41 when the clamping elements 34 are in the region of the axial grooves 41. This situation is shown in FIG. The plunger head 23 is located relative to the coupling plate 16 in a rotational position, which does not correspond to the operating position. At the rear end of the axial grooves 41, however, the spherical surface of the ball head 36 bulges inwards so far that the plunger head 23 together with the clamping elements 34 can rotate relative to the coupling plate 16, wherein the clamping elements 34 from the region of the axial grooves 41 in the area between them lying spherical surface portions 42 pass and engage behind the ball 36. In this position, which is shown in Figure 6, the plunger head 23 is axially locked to the ball head 36.

As can be seen from FIG. 7, the head central part 25 furthermore regularly has fluid channels 43 distributed over its outer circumference. Through these fluid channels 43 tempered fluid, which is supplied via the fluid supply line 22 and the axial bore 21 of the coupling plate 16, from the rear base portion 24 a to the front

Led base portion 24b to meet there on the tempering 26 and to temper this accordingly. So that the fluid emerging from the axial bore 21 of the coupling plate 16 is distributed uniformly to all fluid channels 43 of the head central part 25, the base 24 has a pocket-like recess 44 at its rear end face (FIGS. 5, 6) into which the fluid channels 43 open.

For fluid-tight sealing between the plunger head 23 and the coupling plate 16, a circumferential seal 45 is provided in the form of an O-ring, which in a corresponding circumferential groove of the Plunger head 23 is embedded. This seal 45 encloses the center holes 12 and the pocket-like recess 44 of the base 24 completely. Furthermore, as shown in Figure 8, on the front of the coupling plate 16, a circumferential groove 46 is provided, in which the seal 45 comes to rest when the plunger head 23 is placed on the coupling plate 16. The seal 45 is formed so soft as to allow tilting of the plunger head 23 about the ball head 36 to some extent.

The Temperierkörper 26 is formed in cross-section, as shown in Figure 7, substantially T-shaped and consists of the axially extending shaft portion 28 and a transverse to the axial direction of the support plate 47, on which the device to be tested is placed and held by negative pressure , The Temperierkörper 26, which expediently consists of a good thermal conductivity material, in particular metal such as aluminum, thus not only serves to control the temperature of the components, but is also part of the vacuum system, is provided with the negative pressure at the support surface 4. For this purpose, the shank portion 28 of the tempering 26 with a front pipe socket 48 of the

Head central part 25 and has a central channel 49 which is connected via the pipe socket 48 with the vacuum line 37 of the ball member 32. From the front end of the central channel 49 extend a plurality of vacuum channels 50 to the support surface 4, which open at different locations in the support surface 4. As a result, the component is firmly sucked at different locations, which ensures a very secure mounting of the component on the plunger head 23.

The bearing surface 4 of the tempering 26 is flat and dimensioned so that the body of the components to be tested can rest over the entire surface. The outer diameter of the shaft portion 28 of the Temperierkörpers 26 is suitably much smaller than the inside diameter of the axial recess 27 of the plunger head 23, so that the tempered fluid from all sides can flow from the fluid channels 43 to the tempering 26. In order to improve the temperature of the tempering 26, this can be provided with arranged on the upstream side, surface enlarging ribs. Via lateral recesses 51 in the support plate 47, the tempered fluid from the axial recess 27 can flow laterally outward.

In the context of the invention a variety of variations are possible. For example, it is not essential that a floating coupling plate 16 is provided. The quick lock system could also be located directly between the

Plunger head 23 and the base part 15 can be realized. Furthermore, it is not absolutely necessary that the support plate 47 of the tempering 26 covers the front base portion 24b, as shown in the drawings. Rather, the tempering body 26 could also be arranged completely within the axial recess 27 of the base 24. Furthermore, it would also be possible in this case, the support surface 4 to be arranged for the device so that the walls of the front base portion 24b serve as a support for connecting pins of the components. Although it is particularly advantageous to use four clip elements 34 as second locking means 33, it is readily possible to provide a different number of clip elements 34, but at least two clip elements 34, preferably between two and eight clip elements.

Claims

claims

A plunger for feeding and moving an electronic component, in particular an IC, to and from a contacting device connected to a test device, comprising: a plunger holding part (2),

a plunger pushing part (3) slidably guided on the plunger holding part (2) and movable between a retracted position and an advanced position, the plunger pushing part (3) having a base body (7) and a plunger head (23) attachable to the base body (7) for holding a component by means of negative pressure, characterized in that the plunger head (23) is movably supported on the base body (7), and in that the plunger holding part (2) has a centering means projecting in the direction of the plunger head (23), in the retracted position the plunger slide member (3) is in centering engagement and in the advanced position of the plunger slide member (3) out of centering engagement with the plunger head (23).

2. Plunger according to claim 1, characterized in that the centering means of the Plungerhalteteils (2) consists of at least one centering pin (10) which is attached to the Plungerhalteteil (2) and projecting in the direction of the Piungerkopfs (24), and that the Plungerkopf ( 23) per centering pin (10) has a centering bore (12) into which the centering pin (10) when moving back the Plungerschiebeteils (3) is inserted into its retracted position.

3. Plunger according to claim 1 or 2, characterized in that the base body (7) has a base part (15) and a coupling plate (16), the transverse to the axial direction of the plunger (1) floating on the base part

(15) is held, wherein the plunger head (23) on the coupling plate

(16) is held and the coupling plate (16) per centering pin (10) has a bore (17) through which the centering pin (10) can be passed with lateral play.

4. Plunger according to claim 3, characterized in that at least two centering pins (10) are provided and the base part (15) of the Plungerschiebeteils (3) has guides in which the centering pins (10) are guided longitudinally displaceable.

5. Plunger according to one of the preceding claims, characterized in that the Plungerschiebeteil (3) designed as a guide element, tubular Unterdruckversorgungεleitung (38) which penetrates the Plungεrhalteteil (2) and is guided in this longitudinally displaceable.

6. Plunger according to one of claims 3 to 5, characterized in that the plunger head (23) is rotatably and / or tiltably supported on the coupling plate (16).