Pulp molding transfer apparatus

Abstract

In an example, a pulp molding transfer apparatus includes a fluid pathway between a first side and a second side of a portion of the pulp molding transfer apparatus. In some examples the pulp molding transfer apparatus further includes a flow controlling element which, in use, is moveable between an open position and a flow restricting position in which the flow controlling element at least partially obstructs the fluid pathway. The position of the flow controlling element may be controlled based on a direction of fluid flow through the transfer apparatus.

Description

PULP MOLDING TRANSFER APPARATUSBACKGROUND

[0001] Objects may be formed from a pulp or slurry of material in a pulp moulding process. The pulp or slurry may comprise a mixture of solid material (for example formed from recycled cardboard and / or paper) and a liquid such as water. A pulp moulding die, which may include a screen and a main body, also referred to as a form, may be immersed in a pulp such that a solid material in the pulp accumulates on the screen to form an object in an intended shape. After the object is formed it may be transferred to a pulp molding transfer apparatus. The object may be lifted from the form by the transfer apparatus and may be partially dried while on the transfer apparatus or transferred to another drying apparatus, such as an oven for drying.BRIEF DESCRIPTION OF DRAWINGS

[0002] Non-limiting examples will now be described with reference to the accompanying drawings, in which:

[0003] Figs. 1A and 1 B are cross sections of an example of a pulp molding transfer apparatus;

[0004] Figs. 2A and 2B are cross sections of an example of a pulp molding transfer apparatus;

[0005] Figs. 3A and 3B are cross sections and Fig 3C is a bottom view of an example of a pulp molding transfer apparatus and a pulp molded object;

[0006] Fig. 4 is flowchart of an example of a method for transferring a pulp molded object;

[0007] Fig. 5 is flowchart of an example of a method for transferring a pulp molded object;

[0008] Figs. 6A and 6B show an example of a pulp molding transfer apparatus; and

[0009] Figs. 7A and 7B are cross sections of an example of a pulp molding transfer apparatus.DETAILED DESCRIPTION

[0010] A moulded pulp object may be an object formed using a pulp moulding process. Pulp moulding processes comprise covering a screen of a pulp moulding die with a slurry or pulp. The pulp moulding die may comprise a screen and a form which supports the screen. The slurry, or pulp, may comprise a liquid (e.g. water), and a solid, fibrous material. The fibrous material may be a paper or card, for example recycled paper such as newsprint, cardboard or virgin fibers. The screen of the pulp moulding die may comprise a surface having a shape which corresponds to the shape of a surface of an object to be formed using the die. Various objects may be formed using pulp moulding, for example packaging for eggs, packaging for electronic devices, bedpans, bottles, or cup carriers. The die may be submersed in a bath of the slurry to cover the screen of the die.

[0011] The screen of the pulp moulding die may comprise fluid pathways, such as channels, holes or pores. Holes may be hollow passages through the screen through which material may flow from one side of the screen to another side of the screen. Pores may be small holes or porous zones in the surface which allow the liquid component of the slurry to pass through, but are sufficiently small that the solid, fibrous material accumulates on the surface of the screen to form the object. Channels may be recesses on a surface through which a fluid may flow. In some examples pressure may be reduced behind the die to suck the liquid through the fluid pathways in the screen and to suck the fibrous material towards the surface of the screen. In some examples, a reduced pressure may be insufficient to dry the fibrous material, and therefore additional drying may be achieved by a further drying process, for example by heating the material to cause evaporation of the liquid or by application of pressure. The drying may take place in an oven or between heated metal dies.

[0012] Prior to drying, the object may be transferred from the pulp moulding die to a transfer apparatus. This transfer may comprise supplying air through the screen of the pulp moulding die to blow the object from the pulp moulding die to the transfer apparatus. At least partially concurrently, air may be drawn through the transfer apparatus to suck the object towards the transfer apparatus and hold it thereon. The transfer apparatus may also comprise channels, holes or pores though which the air is drawn.

[0013] While the object is on the transfer apparatus air may continue to be drawn through the apparatus. As the object may still comprise a significant amount of moisture, some moisture may also be drawn through the transfer apparatus which may at least partially contribute towards drying the object. The object may be released from the transferapparatus by reversing the direction of flow of fluid through the transfer apparatus, thereby ‘blowing’ the object off the transfer apparatus to release the object. The object may be released onto a conveyor or other transport system or released directly into a drying apparatus, such as a drying oven or a heated die for further drying.

[0014] Figs. 1 A and 1 B show a cross section of an example of a pulp molding transfer apparatus 100, which may be used for receiving a pulp molded object.

[0015] The pulp molding transfer apparatus 100 comprises a fluid pathway 102 between a first side 104a and a second side 104b of a portion of the pulp molding transfer apparatus 100. In Figs. 1A and 1 B a direction of flow of fluid through the pulp molding transfer apparatus 100 is indicated by hollow arrows. A pulp molded object may be received from a screen of a pulp molding die onto the first side 104a of the pulp molding transfer apparatus 100 by drawing fluid through the fluid pathway 102 in direction indicated in Fig. 1A, thereby sucking the pulp molded object towards the first side 104a. The flow of fluid may be maintained in this direction to hold the pulp molded object on the first side 104a of the pulp molding transfer apparatus 100. The flow of fluid through the fluid pathway 102 may draw moisture from the pulp molded object and thereby assist drying the object. However, the pulp molded object may still be wet, and therefore relatively delicate when it is being released from the pulp molding transfer apparatus 100.

[0016] The first side 104a may have a shape corresponding to a shape of a surface of the pulp molded object. In some examples, a void, or space, may exist within the pulp molding transfer apparatus 100 above the first side 104a and connected to the fluid pathway 102. The first side 104a may comprise multiple openings (e.g. holes or pores) through which fluid may flow from the exterior of the pulp molding transfer apparatus 100 through the void to the fluid pathway 102. In this example, as the first side 104a is shaped to conform to the shape of the pulp molded object and there are multiple openings through which fluid can flow, a force may be distributed across the surface of a pulp molded object when it is being lifted by the pulp molding transfer apparatus 100. A thickness of a wall between the first side 104a and the void may be, in some examples, around 4mm.

[0017] When the pulp molded object is to be released from the pulp molding transfer apparatus 100 the direction of flow of fluid through the fluid pathway 102 may be reversed, as indicated in Fig. 1 B. In use, the pulp molding transfer apparatus 100 may be attached to a pulp molding apparatus which may cause the fluid to flow, for example by applicationof pressure to the second side 104b of the pulp molding transfer apparatus 100, for example using a pump such as a vacuum pump.

[0018] The pulp molding transfer apparatus 100 further comprises a flow controlling element 106 which, in use, is moveable between an open position and a flow restricting position. Fig. 1A shows the pulp molding transfer apparatus 100 when the flow controlling element 106 is in the open position and Fig. 1 B shows the pulp molding transfer apparatus 100 when flow controlling element 106 is in the flow restricting position.

[0019] When the flow controlling element 106 is in the flow restricting position it at least partially obstructs the fluid pathway 102. As used herein, partially obstructing a fluid pathway 102 refers to at least partially blocking the fluid pathway 102 such that the available cross section through which fluid can flow is reduced and may include the fluid pathway being completely blocked such that no fluid can flow through the fluid pathway or being partially blocked so that a reduced flow rate of fluid occurs. In this example the flow controlling element is a round object (e.g. a sphere) and the fluid pathway 102 comprises a conical portion in which the flow controlling element 106 is located. When in the flow restricting position, the flow controlling element 106 is located in a relatively narrow portion of the conical portion of fluid pathway 102 and therefore restricts the flow of fluid by obstructing the fluid pathway 102. In contrast when the flow controlling element 106 is in the open position it is located in the relatively wide portion of the conical portion of the fluid pathway 102 and therefore does not significantly impede the flow of fluid.

[0020] In some examples the flow controlling element 106 substantially completely obstructs the fluid pathway 102 when in the flow restricting position, for example if the flow controlling element 106 is shaped to have a tight fit within the relatively narrow portion of the fluid pathway 102 e.g. the flow controlling element 106 may be a sphere and the fluid pathway 102 may comprise a conical portion with a circular cross section. In other examples the flow controlling element 106 may have a different shape than the cross sectional shape of the fluid pathway 102, thereby allowing some fluid to pass even when it is in the flow restricting position. For example the flow controlling element 106 may have a spherical shape and the fluid pathway 102 may have an elliptical cross section. In such examples fluid may flow through the fluid pathway 102 at a reduced rate when the flow controlling element 106 is in the flow restricting position relative to when in the open position. In other examples the flow controlling element 106 may be shaped to have a tight fit within the relatively narrow portion of the fluid pathway 102 but a bypass exists (e.g. arelatively small hole or channel) which allows a relatively small flow rate of fluid to bypass the flow controlling element 106 when in the flow restricting position.

[0021] In this example the flow controlling element 106 is a round object and the fluid pathway 102 comprises a conical portion in which the flow controlling element 106 is located, however in other examples the flow controlling element 106 and the fluid pathway 102 may have any suitable shape, as described in further detail with respect to Figs. 3A, 3B and 3C below.

[0022] In Fig. 1 A the fluid flows in a first direction from the first side 104a to the second side 104b of the portion of the pulp molding transfer apparatus 100 and in Fig. 1 B the fluid flows in a second direction from the second side 104b to the first side 104a of the portion of the pulp molding transfer apparatus 100. The position of the flow controlling element 106 is controlled based on a direction of fluid flow through the transfer apparatus, in this example when the fluid flows in the first direction the flow controlling element 106 is in the open position and when the fluid flows in the second direction the flow controlling element 106 is in the flow restricting position.

[0023] When the pulp molded object is being transferred from the screen of the pulp molding die to the pulp molding transfer apparatus 100, the flow controlling element 106 is in the open position, and therefore fluid may flow at a relatively high rate through the fluid pathway 102 from the first side 104a to the second side 104b. This allows a relatively large force to be exerted on the pulp molded object to lift it from a screen of a pulp molding apparatus. In contrast, when the flow controlling element is in the flow restricting position fluid may flow at a relatively low rate through the fluid pathway 102 from the second side 104b to the first side 104a. This may reduce the likelihood of damage when releasing a pulp molded object from the pulp molding transfer apparatus 100 because of the reduced rate of flow of fluid when ejecting the pulp molded object (i.e. , the flow of fluid imparts a smaller force on the pulp molded object). In particular, the pulp molded object may be wet and therefore relatively delicate when being ejected, so the reduced force increases the probability that the pulp molded object will be ejected without damage.

[0024] In this example, the position of the flow controlling element 106 is controlled between the open position and the flow restricting position at least partially by the direction of flow of fluid through the pulp molding transfer apparatus 100. For example when fluid flows through the fluid pathway 102 in the first direction, the fluid may exert a force (e.g.an upwards force) on the flow controlling element 106 causing it to move from the flow restricting position to the open position (e.g. in an upwards direction). The force imparted on the flow controlling element 106 may continue while the fluid flows in the first direction, thereby maintaining the flow controlling element 106 in the open position. When the direction of flow is reversed to the second direction, a force (e.g. a downwards force) may be exerted on the flow controlling element 106 causing it to move from the open position to the flow restricting position (e.g. in a downwards direction). This allows the flow controlling element 106 to be controlled without any additional external inputs, thereby providing a simple, low complexity and reliable means for controlling the flow of fluid through the pulp molding transfer apparatus 100.

[0025] Therefore, in this example, the flow of fluid directly acts on the flow controlling element 106 to cause it to move, however, in other examples further means may be provided which contribute to moving the flow controlling element 106. For example the flow controlling element 106 may be passively biased to be in a particular position e.g. due to gravity or a resilient member, such as a spring. In other examples the movement of the flow controlling element 106 may be at least partially actively controlled by an actuator e.g. an electric, hydraulic or pneumatic actuator. For example the direction of flow may be sensed, and the actuator controlled to cause the flow controlling element 106 to move. In other examples, the direction of flow may act directly on the actuator. In still further examples, a controller (which may be a controller which also controls the direction of airflow) may control the position of the of the flow controlling element based on the direction of air flow.

[0026] In this example the flow controlling element 106 is constrained to the conical portion of the fluid pathway 102 by the geometry of the fluid pathway 102 i.e. a horizontal portion of the fluid pathway 102 and the narrow end of the conical portion have a smaller cross section than the cross section of the flow controlling element 106. However, in other examples additional features may be provided to ensure the flow controlling element 106 remains in the correct position e.g. protrusions, ridges, pillars or a cage structure.

[0027] In some examples the fluid pathway may have a minimum diameter of around 2mm to 3mm. In these examples, the flow controlling element 106 may have a diameter of around 5mm.

[0028] In some examples, the pulp molding transfer apparatus 100 is at least partially formed using additive manufacturing. For example a main body of the pulp molding transfer apparatus 100 may be formed using additive manufacturing. In some examples the flow controlling element 106 may also be formed using additive manufacturing. When the main body and the flow controlling element 106 are both formed using additive manufacturing, they may be formed in a single additive manufacturing operation. For example the flow controlling element 106 may be formed within the main body of the pulp molding transfer apparatus 100 during the additive manufacturing operation, thereby reducing assembly complexity, cost and time. In other examples the flow controlling element 106 may be manufactured in separate additive manufacturing operation from the other parts of the pulp molding transfer apparatus 100.

[0029] Additive manufacturing techniques may generate a three-dimensional object, such as the pulp molding transfer apparatus 100 or the flow controlling element 106 through the solidification of a build material. In some examples, the build material is a powder-like granular material, which may for example be a plastic, ceramic or metal powder and the properties of generated objects may depend on the type of build material and the type of solidification mechanism used. Build material may be deposited, for example on a print bed and processed layer by layer, for example within a fabrication chamber.

[0030] In some examples, selective solidification is achieved through directional application of energy, for example using a laser or electron beam which results in solidification of build material where the directional energy is applied. In other examples, at least one print agent may be selectively applied to the build material, and may be liquid when applied. For example, a fusing agent (also termed a ‘coalescence agent’ or ‘coalescing agent’) may be selectively distributed onto portions of a layer of build material in a pattern derived from data representing a slice of a three-dimensional object to be generated (which may, for example, be determined from structural design data). The data may be derived from a digital or data model of the object, e.g. object model data provides a data, or virtual, model of an object to be generated. The fusing agent may have a composition which absorbs energy such that, when energy (for example, heat) is applied to the layer, the build material to which it has been applied heats up, coalesces and solidifies, upon cooling, to form a slice of the three-dimensional object in accordance with the pattern.

[0031] In some examples, when the pulp molding transfer apparatus 100 is generated using additive manufacturing the fluid pathway 102 may be formed by partially fusing build material in portions of the pulp molding transfer apparatus 100. The partially fused build material may allow fluids (gases and liquids such as water and air) to pass through while preventing solid material (such as the fibrous materials used in pulp moulding) from passing through. In other examples, the fluid pathway 102 may comprise holes, pores (i.e. small holes) or channels though the pulp molding transfer apparatus 100.

[0032] Figs. 2A and 2B are cross sections of another example of a pulp molding transfer apparatus 200. In this example the pulp molding transfer apparatus 200 comprises a first fluid pathway 202 in a first portion 210 of the pulp molding transfer apparatus 200, which corresponds to the fluid pathway 102 described in relation to Figs. 1 A and 1 B. The pulp molding transfer apparatus 200 also comprises a flow controlling element 206 as described in relation to Figs 1A and 1 B. Hollow arrows in Figs. 2A and 2B indicate the direction of flow of fluid through the pulp molding transfer apparatus 200.

[0033] The pulp molding transfer apparatus 200 further comprises a second fluid pathway 208 between a first side 204a and a second side 204b of a second portion 212 of the pulp molding transfer apparatus 200. In this example the second fluid pathway 208 is unaffected by the position of the flow controlling element 206. In other words, the open cross section of the second fluid pathway 208 is independent of the position of the flow controlling element 206. Therefore the flow rate of fluid through the second fluid pathway 208 may be the same, when the same pressure is applied, when the flow controlling element 206 is in either position. In other examples the flow rate of fluid through the second fluid pathway 208 may vary when the same pressure is applied and when the flow controlling element 206 is in different positions due to fluid being redirected from the first fluid pathway 202 when the flow controlling element 206 is in the flow restricting position. However in such examples the second fluid pathway 208 remains open and its geometry is unaffected by the position of the flow controlling element 206.

[0034] In this example the first and second fluid pathways 202, 208 join together in the vicinity of the second side 204b in a single passageway, however, in some examples the first and second fluid pathways 202, 208 may be independent throughout the pulp molding transfer apparatus 200.

[0035] In this example, a part of the pulp molded object which is in contact with the first portion 210 of the first side 204a of the pulp molding transfer apparatus 200 may receive substantially the same lifting force as a part of the pulp molded object which is in contact with the second portion 212 of the first side 204a of the pulp molding transfer apparatus 200 when the pulp molded object is being transferred from the screen of the pulp molding die to the pulp molding transfer apparatus 200 because the flow controlling element 206 is in the open position when fluid is being drawn into the pulp molding transfer apparatus 200 from the first side 204a. However, when the pulp molded object is being ejected from the pulp molding transfer apparatus 200 the force exerted on the part of the pulp molded object in contact with the first portion 210 of the first side 204a of the pulp molding transfer apparatus 200 may be less than the force exerted on the part of the pulp molded object in contact with the second portion 212 of the first side 204a of the pulp molding transfer apparatus 200.

[0036] The fluid pathways 202, 208 may for example be arranged such that if the pulp molded object has a relatively delicate region which is susceptible to damage when being ejected from the pulp molding transfer apparatus 200 then this region of the pulp molded object is located adjacent to the first fluid pathway 202 (i.e. in the first portion 210) whereas relatively robust regions of the pulp molded object may be located adjacent to the second fluid pathway 208 (i.e. in the second portion 212). This may reduce the likelihood of damage to the pulp molded object when it is ejected from the pulp molding transfer apparatus 200 because the delicate regions of the pulp molded object receive a smaller ejecting force than the relatively robust regions. In other words, where the flow control element 206 is placed within the pulp molding transfer apparatus 200 may vary depending on the sensitivity to distortion of the geometry of the pulp molded object and mechanical characteristics of the wet fiber material.

[0037] In this example the first fluid pathway 202 comprises a first portion 202a with a first cross sectional dimension and a second portion 202b with a second cross sectional dimension, wherein the second cross sectional dimension is smaller than the first cross sectional dimension. In particular in this example the first and second portions 202a, 202b are wide and narrow parts of a conical portion respectively. When the flow controlling element 206 is in the open position it is located at least partially within the first portion 202a (i.e. relatively wide portion) of the fluid pathway and when the flow controlling element 206is in the flow restricting position it is located at least partially within the second portion 202b of the fluid pathway.

[0038] In this example the flow controlling element 206 is a round object (e.g. a sphere) however in other examples it may be any other suitable shape and the cross section of the first fluid pathway 202 may vary accordingly. For example the flow controlling element 206 may be elliptical, cylindrical, plate shaped (i.e. one relatively thin dimension relative to the other dimensions of the flow controlling element 206), wedge shaped, etc.. The fluid pathway may for example have a tapered section with a rectangular cross section when the flow controlling element 206 is wedge shaped. The shape of the first fluid pathway when the flow controlling element 206 is plate-like is described in further detail with respect to Figs. 3A, 3B and 3C.

[0039] In some examples, the flow controlling element 206 may be integrally formed with the body of the pulp molding transfer apparatus 200. For example the flow controlling element 206 may be a relatively thin plate-like structure which is sufficiently flexible such that when the fluid flows in the first direction it is pushed by the force exerted by the moving fluid into an open position and when the fluid flows in the second direction it is pushed into a flow restricting position by bending. For example a flow controlling element may comprise a flexible arm which bends to move between the open position and flow restricting position by the force exerted on the arm by moving fluid.

[0040] In some examples the flow controlling element 206 may be formed from a different material than the main body of the pulp molding transfer apparatus 200. For example the flow controlling element 206 may be formed from a resilient material (e.g. a metal, plastic or rubber) which deforms or bends to move between the open and flow restricting positions. In some examples the flow controlling element 206 may be a valve, such as a one-way valve.

[0041] In this example the pulp molding transfer apparatus 200 comprises two fluid pathways 202, 208 and comprises two portions 210, 212, however in other examples the pulp molding transfer apparatus 200 may comprise more than two fluid pathways 202, 208 and more than two portions 210, 212.

[0042] Figs. 3A and 3B are cross sections of another example of a pulp molding transfer apparatus 300. Fig. 3C is a bottom view of the another example of a pulp molding transfer apparatus 300. Fig 3A shows a pulp molded object 314 being held on the pulpmolding transfer apparatus 300 by fluid flowing into the pulp molding transfer apparatus 300 through a first plurality of fluid pathways 302 and a second plurality of fluid pathways 308 (for clarity a subset of the fluid pathways 302, 308 are labelled) extending between the first side 304a and the second side 304b of a first portion 310 and a second portion 312 of the pulp molding transfer apparatus 300. In Fig. 3C the first portion 310 is the region within the dashed line and the second portion 312 is the region outside the dashed line surrounding the first portion 310. In this example the second portion 312 is annular in shape and therefore appears on both the left and right sides of the cross sections shown in Figs. 3A and 3B.

[0043] In this example the pulp molded object 314 is a dish (e.g. a plate or a bowl) with a raised rim at its edge. The rim of the pulp molded object 314 is relatively strong compared with the relatively delicate middle portion of the pulp molded object 314. In some examples the force of the ejecting fluid may cause damage or deformation to an unsupported surface, such as a middle portion of the pulp molded object 314. When the pulp molded object 314 is ejected from the pulp molding transfer apparatus 300, in particular when ejected onto a flat surface such as a conveyor belt, the raised rim portion may contact the flat surface before the middle portion of the pulp molded object 314. Therefore if a large ejection force is exerted on the middle portion of the pulp molded object 314, then the unsupported middle portion of the pulp molded object 314 may be more likely to be damaged when the rim portion contacts the flat surface. In other words, the inertia of the pulp molded object 314 when it is ejected may cause the middle portion to continue to move when the rim contacts the flat surface, thereby increasing a probability of damage or deformation when the rim suddenly stops when it contacts the surface.

[0044] In this example, the first plurality of fluid pathways 308 are located within a first portion 310 of the pulp molding transfer apparatus 300 and the second plurality of fluid pathways 308 are located within a second portion 312 of the pulp molding transfer apparatus 300. In this example the first portion 310 of the pulp molding transfer apparatus 300 is located in the middle of the pulp molding transfer apparatus 300 and the second portion 312 is located around the edge of the pulp molding transfer apparatus 300 so that the first portion 310 corresponds to the relatively delicate middle part of the pulp molded object 314 and the second portion 312 corresponds to the relatively robust rim portion of the pulp molded object 314.

[0045] In this example the pulp molding transfer apparatus 300 comprises a flow controlling element which extends between the first plurality of fluid pathways 302. Therefore when the single flow controlling element 306 is in the flow restricting position it at least partially obstructs each of the first plurality of fluid pathways 302 i.e. it can obstruct multiple fluid pathways 302 concurrently. However, in some examples multiple flow controlling elements may be provided to obstruct the fluid pathways 302, for example each of the first plurality of fluid pathways 302 may be provided with an individual flow controlling element such as the flow controlling element 106, 206 described in relation to Figs. 1A to 2B.

[0046] In this example the flow controlling element 306, which extends between the first plurality of fluid pathways 302, comprises a plurality of holes (in some examples it may comprise a single hole), which when the flow controlling element 306 is in the open position allow fluid to flow through but which are blocked by the body of the pulp molding transfer apparatus 300 when the flow controlling element 306 is in the flow restricting position. This is achieved by providing holes in the flow controlling element which are not aligned with the first plurality of fluid pathways 302.

[0047] Although not shown in Figs. 3A, 3B and 3C, the pulp molding transfer apparatus 300 may comprise features to retain the flow controlling element 306 in an appropriate position. For example the pulp molding transfer apparatus 300 may comprise a cage, ridges, channels, pillars or interlocking elements that prevent the flow controlling element 306 from moving laterally within the pulp molding transfer apparatus 300 while allowing it to move between the open position and the closed position. Similarly the flow controlling element 306 may comprise corresponding features to interact with the features of the pulp molding transfer apparatus 300.

[0048] In some examples the pulp molding transfer apparatus 300 may comprise a barrier separating the first and second portions 310, 312 of the pulp molding transfer apparatus 300, as described in relation to Figs. 7A and 7B.

[0049] Fig. 4 is an example of a method 400, which may comprise a method for transferring a pulp molded object.

[0050] The method 400 comprises, in block 402, moving fluid in a first direction through a transfer apparatus to draw a molded pulp object towards the transfer apparatus and the method 400 comprises, in block 404, moving fluid in a second direction throughthe transfer apparatus to release the molded pulp object from the transfer apparatus. The transfer apparatus may be the pulp molding transfer apparatus 100, 200, 300 as described in relation to any of Figs. 1A to 3C.

[0051] The method 400 comprises, in block 406, moving a flow controlling element in the transfer apparatus between an open position and a flow restricting position based on the direction of movement of fluid through the transfer apparatus. In some examples the flow controlling element may be moved passively i.e. moved without active control for example without electrically, hydraulically or pneumatically controlled actuators, and instead moved by the force of fluid moving through the transfer apparatus or due to the force of gravity. When in the flow restricting position, the flow controlling element may at least partially obstruct a fluid pathway of the transfer apparatus and when the flow controlling element is moved to the open position it may increase the cross sectional area of the fluid pathway to allow a higher flow rate of fluid through the fluid pathway. The flow controlling element may be moved by force exerted on the flow controlling element by fluid moving through the transfer apparatus and when the direction of flow of fluid is reversed the change in direction of feree may cause the position of the flow controlling element to change. Therefore the flow of fluid through the transfer apparatus may be restricted based on the direction flow of fluid without any additional control systems. However, in other examples, the flow controlling element may be moved by an actuator or the like, wherein the actuator is controlled directly or indirectly based on the direction flow of fluid.

[0052] In some examples when the flow controlling element is in the flow restricting position the flow controlling element at least partially obstructs a fluid pathway of the transfer apparatus, for example as described in relation to Figs. 1A to 3C. In some examples the fluid pathway may be entirely obstructed so that no fluid can flow through the fluid pathway.

[0053] Fig. 5 is an example of a method 500, which may comprise a method for transferring a pulp molded object. Fig. 5 provides an example of the method 400 of Fig. 4.

[0054] The method 500 comprises, in block 502 generating the transfer apparatus using additive manufacturing and, in block 504 generating the flow controlling element using additive manufacturing. Block 502 and block 504 may be carried out at least in part by processing circuitry, which may comprise at least one processor. In some examples the processing circuitry may be part of, or associated with, an additive manufacturingapparatus. Forming the transfer apparatus and / or the flow controlling element using additive manufacturing may allow the features of these components to be formed in a relatively simple and cost effective manner. For example, characteristics of fluid pathways, such as the size, shape, spacing, porosity, number and / or orientation may be readily varied throughout the transfer apparatus. The transfer apparatus may also be generated with the flow controlling element in place so that when the transfer apparatus and flow controlling element are generated there is no further assembly to do. For example the pulp molding transfer apparatus may be generated with a plurality of fluid pathways, a subset of which may be provided with flow controlling element(s).

[0055] In some examples block 502 and block 504 may comprise generating the transfer apparatus and the flow controlling element in the same additive manufacturing operation. In other examples block 502 and block 504 may comprise generating the transfer apparatus and the flow controlling element in different additive manufacturing operations. In such examples the method 500 may further comprise assembling the flow controlling element and transfer apparatus after they are generated.

[0056] In some examples the method may comprise forming a pulp molded object. For example the pulp molded object may be formed by submersing a screen and a form of a pulp molding die in a slurry comprising a liquid and a fibrous material. Liquid may be drawn, at least in part, through the screen and the form by applying pressure to the form. The pressure may be a reduced, or negative, pressure applied to a back side of the form (i.e. a side facing away from the screen). As the fluid is drawn through the screen, fibrous material may accumulate on the screen thereby forming the pulp molded object. The shape of a surface of the screen may correspond to a shape of a surface of a pulp molded object to be formed. For example the pulp molded object may be packaging for eggs, packaging for electronic devices, bedpans, bottles or cup carriers and the screen may be shaped such that when fibrous material is accumulated on the screen it form the shape of the intended object.

[0057] The method 500 comprises block 402, as described in relation to Fig. 4, which comprises moving fluid in a first direction through a transfer apparatus to draw a molded pulp object towards the transfer apparatus. The fluid may be drawn through the transfer apparatus, for example using a pump such as a vacuum pump to lift the pulp molded object from the screen of the pulp molding die. The fluid may comprise a gas, such as air, and may also comprise liquid, such as water. For example the molded pulp object may be wetfrom the forming process when it is received by the transfer apparatus and may contain a substantial amount of moisture. Therefore drawing fluid into the transfer apparatus through the pulp molded object may draw liquid from within the pulp molded object, thereby assisting in drying of the pulp molded object.

[0058] The method comprises block 506, which is an example of block 406 as described in relation to Fig 4, and comprises moving the flow controlling element from the flow restricting position to the open position in response to a force exerted on the flow controlling element by the fluid moving in the first direction. The movement of the fluid may push the flow controlling element from the flow restricting position in which the flow controlling element substantially obstructs flow of fluid through the fluid pathway to the open position in which fluid can freely flow through the fluid pathway.

[0059] The method 500 comprises block 404, as described in relation to Fig. 4, which comprises moving fluid in a second direction through the transfer apparatus to release the molded pulp object from the transfer apparatus. When the fluid is drawn through the transfer apparatus using a pump, the direction of flow of the fluid may be reversed to flow in the second direction by reversing the direction of the pump.

[0060] The method comprises block 508, which is an example of block 406, as described in relation to Fig 4, and comprises moving the flow controlling element from the open position to the flow restricting position in response to a force exerted on the flow controlling element by the fluid moving in the second direction. The movement of the fluid may push the flow controlling element from the open position to the flow restricting position in which fluid can freely flow through the fluid pathway, thereby reducing the flow rate of fluid through the fluid pathways when ejecting the pulp molded object from the transfer apparatus. This may reduce the probability of damage being caused to the object. Furthermore, when the transfer apparatus comprises a plurality of fluid pathways, the flow controlling element may restrict the flow in a subset of the fluid pathways, thereby allowing the force to be selectively reduced in the most delicate regions of the pulp molded object. In such examples some fluid pathways may not be obstructed by a flow controlling element when the fluid flows in the second direction and therefore the flow rate may be reduced in a subset of the fluid pathways. In some of such examples the fluid pathways which are unaffected by the flow controlling element may be located in the vicinity of regions of the object which are more robust.

[0061] Figs. 6A and 6B are an example of a pulp molding transfer apparatus 600. The pulp molding transfer apparatus 600 may comprise any of the features of the pulp molding transfer apparatus 100, 200, 300 described in relation to Figs. 1A to 3C and may be used to implement the methods 400, 500 described in relation to Figs 4 and 5.

[0062] The pulp molding transfer apparatus 600 comprises a first fluid pathway 602 between a first side 604a and a second side 604b of a first portion 610 of the transfer apparatus 600 which allows fluid to freely move from the first side 604a to the second side 604b and restricts flow of fluid from the second side 604b to the first side 604a. The fluid may be restricted from flowing from the second side 604b to the first side 604a of the first fluid pathway 602 by a flow controlling element within the first fluid pathway 602. In some examples the flow controlling element may be a moveable object which, when the fluid moves from the second side 604b to the first side 604a, moves to a flow restricting position, in which it at least partially obstructs the first fluid pathway 602. While the fluid flows in this direction, the flow controlling element may be maintained in this flow restricting position, thereby reducing the flow of fluid through the first fluid pathway 602. When the fluid moves in the opposing direction i.e. from the first side 604a to the second side 604b, the flow controlling element may move to an open position in which is restricted less, or not at all, by the flow controlling element. In other examples, the flow controlling element may comprise a fixed geometry check valve without any moving parts, such as a Tesla valve. Such a flow controlling element may allow a higher flow rate in one direction relative to the other direction due to the geometry of passageways within the structure.

[0063] The pulp molding transfer apparatus 600 further comprises a second fluid pathway 608 between a first side 604a and a second side 604b of a second portion 612 of the transfer apparatus 600 which allows fluid to freely move from the first side 604a to the second side 604b and to freely move from the second side 604b to the first side 604a. In other words, a fluid may flow freely in both directions through the second fluid pathway 608, in contrast to the first fluid pathway 602 in which the fluid can flow freely in one direction, but not the opposing direction. In examples wherein the first fluid pathway 602 comprises a flow controlling element to restrict the flow of fluid in the first fluid pathway, the second fluid pathway 608 may not comprise such a flow controlling element so that fluid can flow freely in both directions in the second fluid pathway 608.

[0064] Figs 7A and 7B show cross sections of an example of the pulp molding transfer apparatus 600 described in relation to Figs. 6A and 6B. In this example, the pulp moldingtransfer apparatus 700 comprises a flow controlling element 706, a first fluid pathway 702 in a first portion 710 of the pulp molding transfer apparatus 700, a second fluid pathway 708 in a second portion 712 of the pulp molding transfer apparatus 700 as described in relation to Figs. 2A and 2B.

[0065] As described relation to Figs. 1A to 3C the flow controlling element 706 may partially obstruct the first fluid pathway 702 when fluid flows from a second side 704b to a first side 704a of the pulp molding transfer apparatus 700. When fluid flows from the first side 704a to the second side 704b the flow controlling element 706 of the pulp molding transfer apparatus 700 may move to an open position in which it does not obstruct the flow of fluid.

[0066] The pulp molding transfer apparatus 700 further comprises a screen 714. The screen 714 may comprise a plurality of openings, such as holes or pores, which may allow fluids such as liquids and gases to pass through, but which prevent solid fibrous material from passing through. The screen 714 may have a shape which corresponds to a shape of a surface of a pulp molded object. A cavity, gap or space 718 may exist between the screen 714 and first surface 704a of the pulp molding transfer apparatus 700. This may allow substantially uniform pressure to be provided within each portion of the screen 714. Therefore a relatively uniform force may be applied across a region of the pulp molded object in contact with a particular portion of the screen 714 when it is lifted by the transfer apparatus 700.

[0067] In some examples the pulp molding transfer apparatus 700 may comprise a barrier 716 separating the first and second portions 710, 712 of the pulp molding transfer apparatus 700. In this example, the barrier 716 is a seal 716 located within the cavity 718 and may separate the first portion 710 and the second portion 712 of the transfer apparatus 700. The barrier 716 may be located in the space between the main body of the pulp molding transfer apparatus 700 and screen 714 and may isolate the space between the main body of the pulp molding transfer apparatus 700 and screen 714 of each of the portions 710, 712. The barrier 716 may allow a different pressure to form with each of the first and second portions 710, 712 of the pulp molding transfer apparatus 700, thereby allowing a different force to be applied to different regions of the pulp molded object in contact with the different portions 710, 712 of the screen 714 when lifted by the transfer apparatus 700 or when the pulp molded object is ejected from the pulp molding transfer apparatus 700.

[0068] Although this example shows two portions 710, 712 of the pulp molding transfer apparatus 700 and one seal 716, in some examples the pulp molding transfer apparatus 700 may comprise more than two portions and / or more than one seal. For example a pulp molding transfer apparatus comprising two seals may comprise three portions. Similarly, each portion 710, 712 may comprise more than one fluid pathway and the number of fluid pathways may be different in each portion 710, 712.

[0069] In some examples the seal 716 may be attached to, or attachable to, the body of the pulp molding transfer apparatus 700 and / or the screen 714. For example the screen 714 and / or the body of the pulp molding transfer apparatus 700 may comprise grooves or channels to receive the seal 716, or they may comprise locating pins or clips to hold the seal 716 in place. In examples wherein the pulp molding transfer apparatus 700 and / or the screen 714 are generated using additive manufacturing, such features may be generated during the additive manufacturing process to incorporate these features into the pulp molding transfer apparatus 700 and / or the screen 714. In some examples the seal 716 may be attached to the screen 714 or the body of the pulp molding transfer apparatus 700, for example using an adhesive or a fastener.

[0070] In this example the seal 716 has a circular cross section, however in other examples the seal 716 may have a different cross sectional shape e.g. elliptical, square, rectangular, semi-circular, trapezoidal or any other suitable shape. In this example the seal 716 is located within a recess in the first side 704a of the pulp molding transfer apparatus 700.

[0071] In this example, the seal 716 defines two portions 710, 712 of the pulp molding transfer apparatus 700, however, in other examples the pulp molding transfer apparatus 700 may comprise more than one seal which may define more than two portions. In other examples the seal may take different shapes, for example the second portion 712 may encircle the first portion 710.

[0072] The seal 716 may be formed from a material which provides sufficient compressibility, which is deformable and elastic. In some examples the seal 716 comprises a silicone material. In other examples the seal may comprise a rubber or elastomer material. The seal may be formed using an extrusion process to create a seal 716 with a consistent cross section along its length. In some examples the seal 716 may be a composite object and comprise several different materials, for example the seal 716 may comprise a compressible, deformable material (e.g. plastic, silicone, rubber orelastomer) and a stiffening member to maintain the shape of the seal 716, which may be made from metal or plastic. For example the deformable material may comprise a foamed plastic or a silicone sponge material.

[0073] In some examples the seal 716 may permanently separate the first and second portions 710, 712 (i.e. it may not be readily removed from between the screen 714 and main body of the pulp molding transfer apparatus 700). In some examples the seal 716 may be formed by bonding a region of the screen 714 and a region of the body to the pulp molding transfer apparatus 700 together. For example a portion of the screen 714 and body of the pulp molding transfer apparatus 700 may be glued using an adhesive, or they may be welded together. In some examples the screen 714 and / or the body of the pulp molding transfer apparatus 700 may comprise features, such as protrusions, ridges or channels to facilitate such bonding. For example such features may protrude from the screen 714 and / or the body of the pulp molding transfer apparatus 700 to contact the other of the screen 714 and / or the body of the pulp molding transfer apparatus 700 along a linear region to separate the first and second portions 710, 712 and this region may be bonded (e.g. glued or welded) to provide the seal 716.

[0074] In some examples the barrier may be an integral part of the screen 714. For example when the screen 714 is formed by additive manufacturing the barrier may be generated as part of the screen 714. In such examples the first side 704a may comprise a channel, groove or recess into which the barrier fits when the screen is assembled with the rest of the pulp molding transfer apparatus 700.

[0075] The features of the pulp molding transfer apparatus 100, 200, 300, 600, 700 described in relation to Figures 1A, 1 B, 2A, 2B, 3A, 3B, 3C, 6A, 6B, 7A and / or 7B may be combined with the features of any other pulp molding transfer apparatus 100, 200, 300, 600, 700 described herein. The methods 400, 500 described in relation to Figures 4 and 5 may be performed using the pulp molding transfer apparatus 100, 200, 300, 600, 700 or any other suitable apparatus.

[0076] The present disclosure is described with reference to flow charts and / or block diagrams of the methods, devices and systems according to examples of the present disclosure. Although the flow diagrams described above show a specific order of execution, the order of execution may differ from that which is depicted. Blocks described in relation to one flow chart may be combined with those of another flow chart.

[0077] While the method, apparatus and related aspects have been described with reference to certain examples, various modifications, changes, omissions, and substitutions can be made without departing from the spirit of the present disclosure. It is intended, therefore, that the method, apparatus and related aspects be limited only by the scope of the following claims and their equivalents. It should be noted that the above- mentioned examples illustrate rather than limit what is described herein, and that those skilled in the art will be able to design many alternative implementations without departing from the scope of the appended claims.

[0078] The word “comprising” does not exclude the presence of elements other than those listed in a claim, “a” or “an” does not exclude a plurality, and a single processor or other unit may fulfil the functions of several units recited in the claims.

[0079] The features of any dependent claim may be combined with the features of any of the independent claims or other dependent claims.

Claims

CLAIMS1. A pulp molding transfer apparatus comprising: a fluid pathway between a first side and a second side of a portion of the pulp molding transfer apparatus; and a flow controlling element which, in use, is moveable between an open position and a flow restricting position in which the flow controlling element at least partially obstructs the fluid pathway, wherein the position of the flow controlling element is controlled based on a direction of fluid flow through the transfer apparatus.

2. A pulp molding transfer apparatus as claimed in claim 1 wherein the position of the flow controlling element is controlled between the open position and the flow restricting position at least partially by the direction of flow of fluid through the pulp molding transfer apparatus.

3. A pulp molding transfer apparatus as claimed in claim 1 wherein the fluid pathway is a first fluid pathway, and the portion of the pulp molding transfer apparatus is a first portion of the pulp molding transfer apparatus; and the pulp molding transfer apparatus further comprises a second fluid pathway between a first side and a second side of a second portion of the pulp molding transfer apparatus wherein the second fluid pathway is unaffected by the position of the flow controlling element.

4. A pulp molding transfer apparatus as claimed in claim 3 further comprising: a barrier separating the first and second portions of the pulp molding transfer apparatus.

5. A pulp molding transfer apparatus as claimed in claim 1 , wherein the fluid pathway comprises a first portion with a first cross sectional dimension and a second portion with a second cross sectional dimension, wherein the second cross sectional dimension is smaller than the first cross sectional dimension,wherein the flow controlling element is located at least partially within the first portion of the fluid pathway when in the open position, and wherein the flow controlling element is located at least partially within the second portion of the fluid pathway when in the flow restricting position.

6. A pulp molding transfer apparatus as claimed in claim 1 , comprising a plurality of fluid pathways between the first side and the second side of the portion of the pulp molding transfer apparatus, and wherein the flow controlling element extends between the plurality of fluid pathways and when the flow controlling element is in the flow restricting position, it at least partially obstructs each of the plurality of fluid pathways.

7. A pulp molding transfer apparatus as claimed in claim 1 , wherein the pulp molding transfer apparatus is at least partially formed using additive manufacturing.

8. A method comprising: moving fluid in a first direction through a transfer apparatus to draw a molded pulp object towards the transfer apparatus; moving fluid in a second direction through the transfer apparatus to release the molded pulp object from the transfer apparatus; and moving a flow controlling element in the transfer apparatus between an open position and a flow restricting position based on the direction of movement of fluid through the transfer apparatus.

9. A method as claimed in claim 8, wherein moving the flow controlling element between the open position and the flow restricting position comprises at least one of: moving the flow controlling element from the flow restricting position to the open position in response to a force exerted on the flow controlling element by the fluid moving in the first direction; and moving the flow controlling element from the open position to the flow restricting position in response to a force exerted on the flow controlling element by the fluid moving in the second direction.

10. A method as claimed in claim 8, wherein when the flow controlling element is in the flow restricting position the flow controlling element at least partially obstructs a fluid pathway of the transfer apparatus.

11. A method as claimed in claim 8 further comprising: generating the transfer apparatus using additive manufacturing; and / or generating the flow controlling element using additive manufacturing.

12. A pulp molding transfer apparatus comprising: a first fluid pathway between a first side and a second side of a first portion of the transfer apparatus which allows fluid to freely move from the first side to the second side and restricts flow of fluid from the second side to the first side; and a second fluid pathway between a first side and a second side of a second portion of the transfer apparatus which allows fluid to freely move from the first side to the second side and to freely move from the second side to the first side.

13. A pulp molding transfer apparatus as claimed in claim 12 further comprising: a seal separating the first portion and the second portion of the transfer apparatus.

14. A pulp molding transfer apparatus as claimed in claim 12 further comprising: a screen comprising a plurality of openings; and a cavity between the screen and the first side of the pulp molding transfer apparatus, wherein the seal is located within the cavity.

15. A pulp molding transfer apparatus as claimed in claim 12 further comprising: a flow controlling element which partially obstructs the first fluid pathway when fluid flows from the second side to the first side.

Images