In the production of several types of cheese a pressing operation takes place at some time during the manufacturing process. Principally there are two kinds of pressing: a preliminary pressing and a final pressing. Dependent on the type of cheese these two kinds of pressing are utilized separately or successive¬ ly. A preliminary pressing operation is comparatively brief and is carried out in large vats before the cheese is cut into smaller blocks, whereas a final pressing operation is effected in individual, smaller moulds, and for certain cheeses it may last up to about 48 hours. In order not to occupy the pressing machine during the entire pressing period, final pressing moulds have been developed which after being filled, closed and locked may be removed from the pressing machine and- stored somewhere else so as to make the press available for other work. By means of a built-in thrust mechanism, the removed moulds maintain the desired pressure on the curd. This invention relates to such a mould for pressing of cheese and consisting of a bottom part and a cover part composed of an outer cover and a thrust plate substantially similar to the inner shape of the bottom part, which thrust plate is movable in the height direc- tion of the mould and spring biased away from the outer cover whereby the thrust plate is adapted to engage a mass of curd present in the mould and transfer a thrust thereto from the outer cover when the outer cover has been connected to the bottom part in a pressing position by means of releasable locking devices at the outer periphery of the mould.

In a known pressing mould of this type the inter¬ locking of the connected mould parts depends on hooks or

catchers on the cover part engaging behind an edge or rim on the bottom part, thereby keeping the mould parts together. The locking position of the mould parts is thus unambiguously determined, and consequently there is no possibility of adjusting the relative positions of the parts. This implies that during the pressing stage of the manufacturing of the cheese - in which a high degree of product uniformity is evidently aimed at - it is mandatory that exactly the same quantity of curd has been supplied to each mould since otherwise the pressure exerted on the cheese would be larger or smaller than desired, dependent on whether more or less curd was supplied to the mould.

A further deficiency of-this known pressing mould is that it does not allow a change in the final pressing force. Such a change of force may be desirable with cer¬ tain types of cheese, e.g. an increase or descrease of the force in one or more steps during the pressing period. It is an object of the invention to provide a pressing mould of the kind mentioned initially which is designed so as to allow both an adjustment of the pressing force in dependence on the supplied quantity and, if needed, a change of the force one or more times during the pressing period.

With this object in mind the pressing mould according to the invention is characterized in that the cover is adapted to be connected to the bottom in dif¬ ferent height positions relative thereto. Thus, the mutual position of the connected mould parts is in this case not predetermined as in known designs, and by choosing a suitable position and, if necessary, by changing it, a pressing force of exactly the desired magnitude may be ensured at any time. It is a further advantage of the pressing mould according to the invention that cheeses of considerably

varying thickness can now - within certain limits - be produced in the same mould.

Embodiments of the invention will now be described in more detail with reference to the accompa- nying drawings, in which

Fig. 1 is a part-sectional view of a cover part for a first embodiment of a pressing mould according to the invention,

Fig. 2 is a part-sectional view of a bottom part of the pressing mould according to the invention, shown in Fig. 1,

Fig. 3 is a part-sectional view of the assembly of the mould parts, viewed at right angles to Figs. 1 and 2, and , Fig. 4 is a part-sectional view of a second embo¬ diment of a pressing mould according to the invention.

In Fig. 1 there is shown a ' cover part 1 comprising an outer cover 2 and a thrust plate 3. Via two mutually displaceable housing parts 4 and 5 the thrust plate is connected to the outer cover 2 , from which locking tabs 7 protrude. Housing parts 4 and 5 accommodate a thrust member, e.g. a coil spring 6.

The bottom part 10 shown in Fig. 2 comprises a holder having a plate guide 11, the inner side of which forms a support surface for a locking tab 7 indicated in dotted lines. At its top the bottom part is formed with an upwardly diverging collar 12, the outer side of which forms a contact surface for a sleeve 13. When, as shown in Fig. 3, two or more locking devices are arranged on the same side of a pressing mould, the sleeves may be interconnected by means of a rod 14 extending through the sleeves. Rod 14 is spring-biased upwardly by springs 15 arranged in housings 16 and it is movable in the height direction of the mould within grooves 19. The first embodiment of the invention shown in Figs. 1 and 2 operates as follows: curd 20 is first

filled into bottom part 10 following which cover part 1 is mounted, normally by means of a press. Thrust plate 3, which matches the interior shape of bottom part 10, thus abuts on curd 20. While the pressing force is now increased up to the desired magnitude, an automatic and stepless locking together of the mould parts is simul¬ taneously effected by a cooperation between locking tabs 7 and the respective holders.

During assembling of the mould parts the locking tabs 7 pass through slits 21 and through spaces which are formed between the sleeves 13 and the internal sur¬ faces of the plate guides 11 due to the sleeves being depressed by the tabs. As long as the mould parts 1 and 10 move towards each other, the tabs slide freely through said spaces since the locking is effected only when the mould parts attempt to move away from one another - which will ..happen when the external pressing force is relieved and the partially compressed thrust member will try to press the cover part 1 away from the bottom part 10 via the thrust plate 3 abutting against the curd 20. The locking results from the sleeves 13 being, via rod 14 and springs 15, pressed upwards in the tapering gap between the inner surface of a locking tab 7 and the outer surface of collar 12, whereby the locking tab is wedged between the sleeve 13 and the internal surface of guide 11. The mould thus clamped together may now be removed from the press, because the integrated thrust member 6 ensures that the desired pressure on curd 20 is maintained. The locking is stepless because it can be effected irrespective of how far the tabs 7 have passed through the holders, and con¬ sequently there has been provided a pressing mould which, in a simple manner and independent of minor variations in the amount of curd supplied, exerts the correct presssure on the curd.

When the pressing mould shall again be separated after termination of the pressing, this is effected by relieving the spring force on sleeves 13 which then no longer wedge the locking tabs 7. This may for instance be obtained by using a release mechanism, not shown, for pressing rod 14 backwards towards springs 15, following which cover part 1 may be removed. The release mechanism may be disposed on either mould part but alternatively it may be mounted on a, possibly automatical, cover remover, thus having the possibility of being both auto¬ matically and manually activated.

Fig. 4 shows an second embodiment of a pressing mould according to the invention. This mould also con¬ sists of a bottom part 30 and a cover part ^* 31. The cover part is also in this case constituted by an outer cover 32 and a thrust plate 33 movable relative thereto.

The two parts 30 and 31 are locked together by notched bars 34. In this case there are two notched bars on two opposite sides of the mould, i.e. a total of four notched bars. Notched bars provided on the same side of the mould are interconnected by a sleeve 35 and a stif¬ fening flange 36. Along its upper edge bottom part 30 is formed with a rim 37 adapted to cooperate with teeth 38 on the notched bars 34. At their upper ends each pair of notched bars are supported, via sleeve 35, in interior angular guides 39 in a wide, U-shaped section 40 extending downwardly from cover part 32. The substan¬ tially horizontal, internal rolling surfaces 41 of angu¬ lar guides 39 are, at their ends oriented towards the mould, formed with a shallow depression in which sleeve 35 is located in the locked position.

The locking together of the mould parts results from the engagement of teeth 38 - when the desired pressing force has been achieved - behind rim 37. In order to ensure full engagement, flange 36 and hence

notched bars 34 are pressed towards bottom part 30 through an aperture 42 in the outer side of U-section 40. In the locked position sleeve 35 has to be located in the depressions in angular guides 39. In order to release the mould parts cover part 32 is pressed slightly downwards towards bottom part 30. Subsequently notched bars 34 with their teeth 38 are retracted and thus disengaged from rim 37 following which the mould parts may be separated or re-locked together for a different pressing force.

Several modifications of the pressing mould according to the invention are conceivable. The two springs 15 shown in Fig. 3 may for instance be replaced by a single leaf spring profile, and locking member 13 does not have to be a sleeve but may for instance be formed as an eccentrically suspended cam profile.