GB2386153A

GB2386153A - Releasable mounting means

Info

Publication number: GB2386153A
Application number: GB0226265A
Authority: GB
Inventors: Stefan Ferger
Original assignee: Kendro Laboratory Products GmbH
Current assignee: Thermo Electron LED GmbH
Priority date: 2001-11-12
Filing date: 2002-11-11
Publication date: 2003-09-10
Anticipated expiration: 2022-11-11
Also published as: GB2386153B; GB0226265D0; DE10155460A1

Abstract

A releasable mounting means for an object-carrier cassette on a cassette carrier is described, in which a centring strip (17) co-operates with a complementary centring opening (18) in a positively locking manner. A sliding bar (21) is provided in the centring strip (17) and a bar-receiving means (25) is provided at the centring opening (18). The movement of the bar (21) is controllable by way of a control surface (22) at one end of the bar (21). On the object-carrier cassette one edge of the centring opening (18) acts as a bar-release (26) for co-operating with the control surface (22) in such a way that the edge acts upon the control surface (22) when the centring opening (18) and the centring strip (17) are brought into engagement so as to move an end (23) of the bar into fastening engagement with the aperture (25). This procedure takes place when the object-carrier cassette is placed on the cassette carrier.

Description

M&C Folio: GBP86836 DocuTnent: 873587 Mountine Means for an Obiect-

Carrier Cassette on a Cassette Carrier and Method of Mountine The invention relates to a releasable mounting means for an object-carrier cassette on a cassette carrier, in which a centring strip co-operates with a complementary centring opening in a positively locking manner, and to a method of mounting an object-carrier cassette on a cassette carrier.

In the present context, object carriers are understood to be for example open trays or closed containers for receiving samples, which are used in particular in research and industrial production. Object-carrier cassettes are used for receiving a plurality of ob ject carriers one above the other in the manner of a tower, one insertion space being associated with each object carrier in such a way that the object carriers can be removed individually by way of an open side of the object- carrier cassette. By means of object carrier cassettes of this type object carriers are inserted for example into handling appliances such as breeding cabinets and the like and are temporarily stored there. The cassette carrier can be a part connected in a fixed and immovable manner to the appli ance in question. Object-carrier cassettes are also frequently arranged on a turntable. In such a case the cassette carrier is constructed in the form of a rotating disc. An arrangement of this type for use in an air-conditioned cabinet is described for example in WO 98/05753.

In order to ensure an automatic loading and removal of the object carriers into an object-carrier cassette or out of an object-carrier cassette respectively, a precise orienta tion and positioning on the cassette carrier is required. In addition, it is necessary for the object- carrier cassettes to be held immovably in place in order to allow a loading or removal procedure to take place without difficulty on the one hand and to prevent

damage on the other hand. During the removal or during the loading the object-carrier cassettes have to absorb forces which occur in an unavoidable manner during the gripping, extraction and insertion of the object carriers. As the height of the object carrier cassettes increases, leverages also occur with respect to the bearing points of the cassettes which can result in an undesired tilting movement or change in position.

It is known for releasable mounting means in the form of holding magnets or spring-loaded thrust members to be arranged between the centring strips and the centring openings. These mounting means also usually meet the requirements in a reliable manner. Nevertheless, in individual cases it cannot be ruled out that an object-

carrier cassette will be tilted out of its defined position at least for a short time, for example when an object carrier is inserted or removed.

The object of the invention is to disclose a mounting means and a method of the type defined in the introduction, which will ensure a particularly secure fastening on a

cassette carrier and which will nevertheless not obstruct the manipulation.

This object is attained in that a bar is provided in the centring strip and a bar-

receiving means is provided at the centring opening, the movement of the bar is control-

lable by way of a control surface, and a bar-release for co-operating with the control surface is arranged at the centring opening in such a way that the bar-release engages with the control surface when the centring opening and the centring strip are brought into engagement.

With respect to the method, the object is attained by the following method steps: - placing the object-carrier cassette on the cassette carrier on an edge of the object-

carrier cassette at a tilting angle with respect to the cassette carrier, - restricting the movement of the object-carrier cassette whilst reducing the tilting angle until the object-carrier cassette is placed completely on the object carrier, and - releasing a bar in a manner controlled by the tilting movement.

The invention has the advantage that a forcible locking automatically takes place when an object-carrier cassette is inserted on the cassette carrier. The user need not actively intervene for this purpose, so that manipulation errors are eliminated. The unlocking also takes place automatically when the object-carrier cassette is lifted off.

As a whole there is no change in the previously customary procedures for the user, so that no operating guidance is necessary. The invention has the further advantage that no additional space requirement is necessary since all the necessary technical elements can be incorporated in centring openings and centring strips of conventional design.

The bar release and the control surface are suitably in the form of cooperating cam or wedge surfaces for displacing the bar into a position in which it is engaged with a bar receiving means when the centring opening and the centring strip are brought into-

engagement. Preferably, when engaged, the bar release and the control surface remain engaged with one another to keep bar the engaged with the bar receiving means.

The bar control can be exerted particularly easily in that the control surface is designed in the form of a face curved towards the outside, preferably in the form of a surface of a segment of a sphere or a segment of a cylinder.

An alternative preferred further development of the invention consists in that the control surface is designed in the boron of a control slope. control slope is easy to pro-

duce and is relatively wear-free in operation.

It is particularly advantageous for the bar to be designed in the form of a sliding bar which is pre-stressed in a spring-loaded manner away from the locking position, and for the control surface to be formed at one end of the bar and to project from one side of the centring strip in the unlocked position. The mounting and assembly of a sliding bar of this type is particularly simple and therefore inexpensive and requires little maintenance since no reversing elements or joints are required.

The mounting means according to the invention is particularly well protected from

critical effects of force during the loading and removal of object carriers on account of the fact that the locking point is situated at the side of the centring strip which is towards the removal / loading and on which pressure and force from the object-carrier conveying device act. The base of the object-carrier cassette is prevented from being levered out by the locking at this point in a particularly effective manner.

A use which is particularly reliable in operation is made possible by the fact that the side of the centring strip facing the locking side is designed in the form of a stop for the cassette carrier. This ensures that the bar release is orientated precisely onto the control surface and the bar engages precisely in the bar opening.

In order to keep the design of the object-carrier cassettes as simple as possible, a preferred arrangement of the invention consists in that the centring strip is arranged on the cassette carrier and the centring opening is arranged in the cassette base. In this way the object-carrier cassettes contain no movable parts. The assembly of the movable parts of the mounting means is thus limited to the cassette carriers, which is advan-

tageous on grounds of costs and makes possible the refitting of existing appliances.

The invention is described in greater detail below with reference to two embodi-

ments illustrated in the drawing, in which, in a diagrammatic manner Fig. 1 is a perspective illustration of parts of a storage station for object carriers; Fig. 2 is a plan view of a base plate of an object-carrier cassette; Fig. 3 is a perspective view of a centring strip - partly in section - in accordance with a first embodiment; Fig. 4 is a longitudinal section through the centring strip as shown in Fig. 3; Fig. 5 is a crosssection through the centring strip along the section line V-V in Fig. 4; Fig. 6 is a longitudinal section through a centring strip in accordance with a second embodiment; Fig. 7 is a cross-section through the centring strip as shown in Fig. 6 along a section

line VII-VII, and Fig. 8 shows a phase during the insertion and locking of an object-carrier cassette on a cassette carrier.

Fig. 1 shows a storage station for a plurality of object-carrier cassettes 10, only one of which is illustrated, in order to keep the Figure easy to comprehend. The storage station 10 has a remote-controlled, automatic conveying device 11 by way of which object carriers 12 are removed from an object-carrier cassette 10 or are inserted into an object- carrier cassette 10. A storage station of this type can be arranged inside or out-

side a laboratory appliance. A typical arrangement is inside an airconditioned cabinet and, in particular, in a breeding cabinet (not shown).

An object-carrier cassette 10 essentially comprises a tower-shaped structure with two lateral walls 13, between which storage points 14 for object carriers 12 are arranged one above the other in the manner of shelves. The storage points 14 are fixed by bearing points or horizontal bearing rails 15. Approximately 20 bearing points are typi-

cally arranged one above the other inside an object-carrier cassette 10. Object-carrier cassettes 10 of this type are also referred to as stackers. Object carriers 12 are extracted or inserted by means of the conveying device 11 by way of an open side of the object-

carrier cassette 10.

In the example illustrated the object-carrier cassettes 10 are arranged in a star shape in the manner of a turntable on a rotating disc 16 acting as a cassette carrier, in such a way that their open sides for the loading and for the removal of object carriers 12 face outwards. The respectively desired object-carrier cassette 10 is moved and orientated towards the conveying device 11 by rotation of the rotating disc 16, the conveying device 11 being able to access a storage point 14 in a desired manner by way of a verti-

cally adjustable gripper or the like.

The object-carrier cassettes 10 are each fastened to the rotating disc 16 by way of a releasable mounting means. Each mounting means comprises a centring strip 17 which is arranged radially on the rotating disc 16. Each centring strip 17 co-operates with a

complementary centring opening 18 in a base plate 19 (Fig. 2) of the object-carrier cassette 10 in a positively locking manner. If an objectcarrier cassette 10 is placed on the rotating disc 16, then in the course of the co-operation of the centring strip 17 and the centring opening 18 the object-carrier cassette 10 is orientated in the correct manner on the rotating disc on the one hand and is correctly positioned and prevented from tilting by the positive locking on the other hand. In the example illustrated each centring strip 17 is additionally provided along a longitudinal side and an end face with spring-loaded pressure stubs 20 which produce a mounting with non-positive locking.

The centring opening 18 extends centrally between the lateral walls 13 and parallel to them, i.e. a narrow side of the centring strip 17 is directed towards the open side of the associated object-carrier cassette 10 in each case.

It is clear from Figs. 3 to 5 that a rod-shaped sliding bar 21 is arranged inside each centring strip 17, and it extends parallel to the longitudinal axis of the centring strip 17.

The bar 21 passes through the centring strip 17 from one narrow side to the other, the inwardly directed end of the bar (with respect to the rotating disc 16) having a control surface designed in the forte of a control slope 22. The end of the bar (bar catch 23) used for locking is situated on the narrow side of the centring strip 17 situated on the outside. The bar 21 is pre-stressed in a spring-loaded manner by a helical spring 24 contrary to its locking position, so that in this position the bar catch 23 terminates flush with the narrow side of the centring strip 17 on the outside. This unlocking position is illustrated in Figs. 3 to 6. In the unlocking position the control slope 22 projects out of the narrow side of the centring strip 17 with the slope directed upwards. If a force is exerted from above upon the control slope 22 as shown by arrow A, then the bar 21 is deflected against the spring force until it reaches its locking position and the bar catch 23 projects out of the centring strip 17. The bar 21 is kept in this position as long as the control slope 22 is loaded. As soon as the control slope 22 is released, the helical spring 24 pushes the bar 21 back into its unlocking position.

The bar 21 co-operates on the side of the cassettes with a bar opening 25 which is formed by means of the base plate 19 of the object-carrier cassette 10. In the simplest

case the bar opening 25 is Droned by a cavity behind the base plate 19 into which the bar catch 23 can engage. In addition, the control slope 22 co-operates with a bar release 26 which in the example illustrated is formed in a simple manner by an edge portion of the centring opening 18 (Fig. 2). The control slope 22 and the bar release 26 together form a wedge gear.

In the case of the second embodiment of a centring strip 17' illustrated in Figs. 6 to 8, the same parts are provided with the same reference numbers as in the first example as shown in Figs. 3 to 5. The second embodiment of the centring strip 17' differs from the first embodiment 17 essentially by the design of the control surface In addition, it may be seen from Fig. 7 that the bar catch 23 is constructed in the form of a hemi-

spherical end 32 of the bar 21.

In the case of the second embodiment the control surface is designed in the fonn of a surface of a quadrant-shaped segment 31, i.e. the control surface constitutes a face curved towards the outside. The quadrantshaped segment 31 is the upwardly facing part of a hemisphere 33 which forms the end of the bar. The second, downwardly facing quadrant 34 is part of a catch closure which is described in greater detail in con-

junction with Fig. 8.

In Fig. 8 an object-canter cassette 10 is partially cut away in the region of its base plate 19, so that the region of the bar release is visible.

The locking is carried out in the following manner as shown in Fig. 8: The object-

carrier cassette 10 is placed with its lower edge situated on the outside (with respect to the rotating disc 16) on the rotating disc 16, and the corresponding area of the centring opening 18 is orientated on the centring strip 17', whilst the side situated on the inside is pivoted or tilted away upwards so as to form a tilting angle a. The object-carrier cassette 10 is then tilted downwards. The bar release is controlled by the tilting move-

ment. In this case the edge of the centring opening 18 acting as the bar release 26 first comes into contact with the quadrant 31 - acting as the control surface- at the end of the bar and exerts a shearing force upon the bar release. The bar release 26 is provided with a ramp-shaped slope 36, so that it can slide satisfactorily on the quadrant 31.

When the object-carrier cassette 10 is lowered farther at a decreasing tilting angle a and is finally positioned completely on the rotating disc 16, on one side the bar opening 25 (Fig. 2) moves into the region in which the bar catch 23 or the hemisphere 32 respec-

tively engages under it, whilst the bar 21 is completely extended. At the same time the bar release 26 is moved past the upper quadrant 31. This makes it possible for the bar 21 to be moved back again slightly by spring pressure and to engage behind the bar release 26 behind a catch projection 37, without, however, the bar 21 moving back into its unlocked position. The catch closure is thus formed. The spring-loaded pressure stubs 20 as well as the hemisphere assist the secure seating of the object-carrier cassette 10. The bar is thus actuated and locked in a simple manner by placing the object-carrier cassette 10 on one edge and tilting the object-carrier cassette 10, without the user having to intervene actively in the manipulation of the bar.

For unlocking, the object-carrier cassette 10 is merely lifted in the reverse sequence first about the edge situated on the outside. In this case the bar release 26 first moves the hemispherical end of the bar 21 back and thus releases the catch closure. During this, the bar 21 is first moved in the locking direction, as the catch projection 37 presses upon the quadrant-shaped counter member 34 of the catch closure, until the catch projection 37 has moved past the hemisphere 33. The control surface or the upper quadrant 31 is then released. Since this causes a complete return of the bar 21 as a result of the spring force, the bar opening 15 (Fig. 2) at the inner side of the object-

carrier cassette 10 is also released and the object-carrier cassette 10 can be removed, without the user having to actuate the bar 21.

The present invention has been described above by way of example only and modifications can be made within the invention.

Claims

CLAIMS:

1. A releasable mounting means for an object-carrier cassette on a cassette carrier, in which a centring strip co-operates with a complementary centring opening in a positively locking manner, characterized in that a bar is provided in the centring strip and a barreceiving means is provided at the centring opening, the movement of the bar is controllable by way of a control surface, and a bar-release for co-

operating with the control surface is arranged at the centring opening in such a way that the bar-release engages with the control surface when the centring opening and the centring strip are brought into engagement.

2. A mounting means according to Claim 1, characterized in that the control surface

is designed in the form of a face curved towards the outside.

3. A mounting means according to Claim 2, characterized in that the control surface is designed in the form of a surface of a segment of a sphere or a segment of a cylinder.

4. A mounting means according to Claim 1, characterized in that the control surface is designed in the form of a control slope, and the bar release is formed by an edge of the centring opening.

5. A mounting means according to one of the preceding Claims, characterized in that a locking point is situated on the side of the centring strip facing the removal side.

6. A mounting means according to one of the preceding Claims, characterized in that the bar is designed in the form of a sliding bar which is pre-stressed in a spring-loaded away from locking position, and the control surface is Coined at one end of the bar which projects beyond the edge of the centring strip in the unlocked position.

7. A mounting means according to one of the preceding Claims, characterized in that a catch projection is formed on the bar-release and a counter member is formed on the end of the bar, and they co-operate as a catch closure.

8. A mounting means according to one of the preceding Claims, characterized in that the end of the bar acting as a catch closure is made hemispherical, wherein one half of the hemisphere acts as a control surface and the other half as a counter member for the catch projection.

9. A mounting means according to one of the preceding Claims, characterized in that the centring strip is arranged on the cassette carrier and the centring opening is arranged in the cassette base.

10. A method of mounting an object-carrier cassette in a releasable manner on a cassette carrier, characterized by the following method steps: placing the object-carrier cassette on the cassette carrier on an edge of the object-carrier cassette at a tilting angle with respect to the cassette carrier, - restricting the movement of the object-carrier cassette whilst reducing the tilting angle until the object-carrier cassette is placed completely on the object carrier, and - releasing a bar in a manner controlled by the tilting movement.

11. Use of the mounting means according to Claim 1 in an air-conditioned cabinet.

12. A releasable mounting means for an object-carrier cassette on a cassette carrier substantially as herein described with reference to figures 2 to 5 or 6 to 8 of the accompanying drawings.