SUCTION VALVE

TECHNICAL FIELD

The invention relates to a suction valve configured to be attached to a conduit that is arranged to provide a suction force for sucking liquid from a vessel. BACKGROUND

Industrial scale food handling often involves the use of large vessels, such as tanks, that contain more or less liquid foodstuff. When such a vessel containing a liquid is to be emptied it is often important to minimize the amount of liquid that remains in the vessel after being emptied, i.e. it is typically desired to completely empty the vessel. Arrangements used for emptying vessels of liquid include conduits, such as a simple hose or tube, equipped with a nozzle comprising a suction valve through which liquid may be sucked out of the vessel. There are a multitude of nozzles having suction valves in the prior art, most of which have drawbacks such as the inability to enable suction of liquid at the very bottom of the vessel at a point in time when the vessel is almost empty. SUMMARY

In view of the above, an object of the present disclosure is to overcome or at least mitigate at least some of the drawbacks related to prior art suction valves.

This is achieved in a first aspect by a suction valve that is configured to be attached to a conduit, which is arranged to provide a suction force for sucking liquid from a vessel. The suction valve comprises an outer body comprising a suction inlet and configured to be connected to the conduit. An inner body is movably arranged within the outer body and a spring is arranged to exert a force on the inner body to press the inner body in a direction towards the suction inlet such that the inner body seals the suction inlet to thereby set the suction valve in a closed state. The inner body is further arranged to move in a direction away from the suction inlet when a suction force applied by the conduit is larger than the force exerted by the spring to thereby set the suction valve in an open state to allow liquid to be sucked from the vessel through the suction inlet and into the conduit.

In other words, such a suction valve is advantageous in that it enables suction of liquid at the very bottom of the vessel at a point in time when the vessel is almost empty. In a second aspect there is provided a suction system for sucking liquid from a vessel. Such a suction system comprises a suction valve as summarized above, a conduit to which the suction valve is attached and a suction device connected to the conduit to provide a suction force for sucking liquid from the vessel.

In a third aspect there is provided a method of using a system as summarized above for sucking liquid from a vessel. Such a method comprises lowering the suction valve into the liquid and applying suction by the suction device to place the suction valve in the open state and thereby remove liquid from the vessel by drawing the liquid into an end suction inlet and a lateral suction inlet of the outer body.

These second and third aspects provide effects and advantages corresponding to the effects and advantages of the first aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 a is a cross-sectional side view of a suction valve in a closed state,

figure 1 b is a cross-sectional side view of the suction valve of figure 1 a in an open state, figure 1 c is a cross-sectional top view of the suction valve of figures 1 a and 1 b, figure 1d is a cross-sectional perspective view of the suction valve of figures 1 a-c, figure 1 e is a partial, cross-sectional side view of the suction valve of figures 1 a and 1 b in an intermediate state,

figure 2a is a cross-sectional side view of a suction valve according to a second embodiment and in a closed state,

figure 2b is a cross-sectional side view of the suction valve of figure 2a in an open state, figure 2c is a cross-sectional top view of the suction valve of figures 2a and 2b, and figure 2d is a cross-sectional perspective view of the suction valve of figures 2a-c, figure 3 schematically illustrates a system comprising a suction valve, and

figure 4 is a flowchart of a method of using a system comprising a suction valve.

DETAILED DESCRIPTION

Referring first to figures 1a-e, and with reference also to figure 3, a suction valve 100 is attached to a conduit 190 that is arranged to provide a suction force for sucking liquid 391 from a vessel 302. The liquid 391 may be liquid food.

The suction valve 100 comprises an outer body 102 comprising, in one end of the suction valve 100, a suction inlet 1 1 1 and configured to be connected to the conduit 190 (the conduit also referred to with reference numeral 306 in figure 3) at another end of the suction valve 100.

An inner body 104 is movably arranged within the outer body 102. The outer body 102 and the inner body 104 may be concentrically arranged in relation to each other around a longitudinal axis 108. The inner body 104 is then arranged to move in directions -Y, Y along the longitudinal axis 108. As exemplified, the suction valve 100 is generally circularly symmetric with respect to the longitudinal axis 108. However, other symmetries may be foreseen in other embodiments, such as any polygon-shaped cross- section.

A spring 106 arranged to exert a force 196 on the inner body 104 to press the inner body 104 in a direction -Y towards the suction inlet 1 1 1 , such that the inner body 104 seals the suction inlet 1 1 1 to thereby set the suction valve 100 in a closed state P1.

The inner body 104 is arranged to move in a direction Y away from the suction inlet 1 1 1 when a suction force 195 applied by the conduit 190 is larger than the force 196 exerted by the spring 106, to thereby set the suction valve 100 in an open state P21 to allow liquid 391 to be sucked from the vessel 302, through the suction inlet 1 1 1 and into the conduit 190.

The suction inlet 1 1 1 of the outer body 102 has an end suction inlet 1 12 and a lateral suction inlet 1 14. The inner body 104 has an end sealing surface 1 10, a lateral sealing surface 1 16 and a liquid passage 1 18 for allowing liquid to flow through the inner body 104. In the closed state P1 , the inner body 104 is in a first position along the longitudinal axis 108, in which first position the end sealing surface 1 10 seals the end suction inlet 1 12 while the lateral sealing surface 1 16 seals the lateral suction inlet 1 14. As exemplified, the lateral inlet 1 14 is in the form of a plurality of circular holes distributed around the circumference of the outer body 102. However, the lateral inlet 1 14 may be comprised of any appropriate number of holes having any appropriate shape and distribution on the outer body 102.

In the open state P21 , the inner body 104 is in a second position along the longitudinal axis 108, in which second position the end sealing surface 1 10 is retracted from the end suction inlet 1 12 and the lateral sealing surface 1 16 is retracted from the lateral suction inlet 1 14.

The inner body 104 is arranged to move in the direction Y away from the end suction inlet 1 1 1 when an external force 197 that is applied on the inner body 104 is larger than the force exerted by the spring 106. The external force 197 can be applied by pressing of the suction valve 100 towards a bottom of the vessel 302. Thereby the suction valve 100 can be set in an intermediate state P22 to allow liquid 391 to be sucked from the vessel 302 through the end suction inlet 1 12 and into the conduit 190. In the intermediate state P22, the inner body 104 is in a third position along the longitudinal axis 108. In the third position, the end sealing surface 1 10 is retracted from the end suction inlet 1 12 while the lateral sealing surface 1 16 still seals the lateral suction inlet 1 14. The inner body 104 has a lateral inlet 120 that is located above the liquid passage 1 18 of the inner body 104. When the suction valve 100 is set in the open state P21 , a circumferential channel 122 leading to the lateral inlet 120 of the inner body 104 is formed between the outer body 102 and the inner body 104. The circumferential channel 122 thereby allows liquid 191 to flow through the lateral inlet 120 of the inner body 104 and into the conduit 190. This circumferential channel 122 may then improve cleaning of the suction valve 100, when cleaning liquid is sucked through the suction valve 100. The lateral inlet 120 is in the form of a plurality of circular holes distributed around the circumference of the inner body 104. However, the lateral inlet 120 may be comprised of any appropriate number of holes having any appropriate shape and distribution on the inner body 104.

The inner body 104 has a protrusion 124 that protrudes, when the suction valve 100 is in the closed state P1 , beyond the end suction inlet 1 12 of the outer body 102. As illustrated in figures 1 a-e, the protrusion 124 may have a convex shape. However, other embodiments may comprise protrusions having other shapes, for example protrusions having the shape of truncated cones.

Such a protrusion 124 may be arranged on the end sealing surface 1 10, the end sealing surface 1 10 being supported by legs 126 that protrudes from a cylindrically shaped section 128 of the inner body 104, 204. The liquid passage 1 18 of the inner body 104, 204 is formed by spacings 129 between the legs 126. Whereas the suction valve 100 is exemplified having eight equidistant legs 129, it is to be noted that the some

embodiments may comprise any other number of legs having any appropriate length and distribution along the circumference of the cylindrically shaped section 128.

When the suction valve 100 is in the intermediate state P22 (see Fig. 1 e), the lateral inlet 1 14 of the outer body 102 is sealed while the end inlet 1 12 of the outer body 102 is open. This intermediate state P21 is advantageous in that it enables an effective suction of liquid from the vessel 302 at a point in time when the vessel 302 is almost empty, as indicated by a low liquid level 393 in figure 3. When the liquid in the vessel 302 is at the low liquid level 393, then the lateral inlet 1 14 may be located above the low liquid level 393. However, by the fact that the lateral inlet 1 14 is sealed by the lateral sealing surface 1 16, drawbacks related to sucking the atmosphere above the low liquid level 393 are avoided. As the skilled person will realize, it is in most food product contexts

disadvantageous to suck a mixture of liquid and, e.g., air via the conduit 190. At the same time, the suction valve 100 has a high suction capacity when it is in the open state P21 , since liquid then can be sucked through both the end suction inlet 1 12 and the lateral suction inlet 1 14.

The outer body 102 may comprises a first part 130 and a second part 132 that are attached to each other to hold the inner body 104. The second part 132 may comprise a first spring abutment surface 134 that faces the inner body 104 and the inner body 104 may comprise a second spring abutment surface 136 that faces the second part 132.

The spring 106 is then in contact with and biased between the first and the second spring abutment surfaces 134, 136. Further, the first part 130 may comprise a first stop surface 138 against which the inner body 104 abut when the suction valve 100 is in the closed state P1 and the second part 132 may comprise a second stop surface 140 against which the inner body 104 abut when the suction valve 100 is in the open state P21. As can be seen in figures 1 a-b, the first stop surface 138 ensures a tight fit between the outer body 102 and the inner body 104 and thereby a secure sealing of the lateral inlet 1 14 of the outer body 102. Moreover, the second stop surface 140 provides a limit on how far the inner body 1034 may move in the Y-direction.

Figures 2a-d illustrate a suction valve 200 that is similar to the suction valve 100 illustrated in figures 1 a-d. The suction valve 200 of figures 2a-d illustrates more compact embodiments that the embodiments illustrated in figures 1 a-e. In figures 2a and 2d, the suction valve 200 is in the closed state P1 and in figure 2b it is in the open state P21.

The suction valve 200 comprises an outer body 202 and an inner body 204 and a spring 206. Similar to the suction valve 100, the outer body 202 comprises a first part 230 and a second part 232 that are attached to each other to hold the inner body 204. The second part 232 is configured, similar to the second part 132 of the suction valve 100, to be connected to a (not shown in figures 2a-d) conduit that is arranged to provide a suction force for sucking liquid from a vessel.

In addition to features that correspond to features of the suction valve 100, the second part 232 of the suction valve 200 has a cylindrically shaped section 242 having cut-outs 244. The cylindrically shaped section 242 is configured such that it operates as a spring abutment surface that is similar to the spring abutment surface 134 of the second part 132 of the suction valve 100 in figures 1 a-e. The cut-outs 244 maximize the internal cross-section of the outer body 232 while retaining the spring abutment capability of the cylindrically shaped section 242. Consequently, the cut-outs 244 maximize the flow of liquid when the suction valve 200 is in the open state P21 when liquid is being sucked through the suction valve 200.

Turning now to figure 3, a suction system 300 for sucking liquid 391 from a vessel 302 is schematically illustrated. The suction system 300 comprises a suction valve such as the suction valve 100 of figures 1 a-e (or the suction valve 200 of figures 2a-d). The suction system 300 further comprises a conduit 306 to which the suction valve 100 is attached. A suction device 308, e.g. an appropriately configured suction pump, is connected to the conduit 306 to provide a suction force for sucking liquid 391 from the vessel 302. The suction device 308 connects to further arrangements via a further conduit 312, the details of which are outside the scope of the present disclosure.

Turning now to figure 4, and with continued reference to figures 1 a-e and figure 3, a method of using the system 300 for sucking liquid 391 from a vessel 302 comprises a number of actions that begin with a lowering 410 of the suction valve 100 into the liquid 391 . Suction is then applied 420 by the suction device 308 to place the suction valve in the open state P21 and thereby remove liquid 391 from the vessel 302 by drawing the liquid into the end suction inlet 1 12 and the lateral suction inlet 1 14 of the outer body 102, 202.

A further action of applying suction 430 by the suction device 308 may then be performed. In this application of suction 430, a suction force is applied that is smaller than the force exerted by the spring 106. The suction valve 100 is thereby placed in the closed state P1. By pressing 440 the protrusion 124 of the inner body 104 towards a bottom part 310 of the vessel 302, the suction valve 100 is then placed in the

intermediate state P22 to thereby remove liquid 391 from the vessel 302 by drawing the liquid into the end suction inlet 1 12 while the lateral suction inlet 1 14 is closed. That is, liquid 393 at the bottom 310 of the vessel 302 is being sucked, providing the advantages as described above.

From the description above follows that, although various embodiments of the invention have been described and shown, the invention is not restricted thereto, but may also be embodied in other ways within the scope of the subject-matter defined in the following claims.